201033404 六、發明說明： 【發明所屬之技術領域】 本發明係關於半導體裝置之成為連接端子之突起電極之 形成方法及置換鍍金液。 【先前技術】 半導體裝置由於其電晶體及配線之尺寸縮小，其每單位 面積之積集度升高’因此製造成本降低。另一方面，半導 體裝置之功能正在大規模化及多樣化。半導體裝置之製造 成本中’雖製造半導體晶片之步驟（以下稱前半步驟）之成 本大大減少，但爲了完成電子零件而進行封裝，組裝於電 子電路基板之步驟（以下稱後半步驟）之成本卻幾乎未減 少。該後半步驟中之成本在半導體裝置之製造成本中占較 大比例之傾向變強，成為對半導體裝置之製造成本降低之 較大阻礙要因。 液晶面板驅動用之半導體裝置中，除了市場嚴格之低價 • 要求以外，尋求的是高品質且多端子化，為與此等對應， 後半步驟所花費之成本將占全體之過半。再者，近年來貴 金屬價格不斷持續高潘。因此，形成於液晶面板驅動用: ，導體裝置中之半導體晶片之突起電極(以下亦稱凸塊)，正 從由金（Au)構成凸塊整體之先前的構成，轉變為凸塊之主 要構成部為非貴金屬’只有表面由金構成之新方式的構 成。作為形成如此新方式之凸塊之方法，已知有將凸塊之 =構成部採㈣（Ni)合金，於其表面利用無電解錄敷技 術實施鍍金之方法，該方法係對成本下降有利之方法 145326.doc 201033404 者，凸塊之鍍金，爲了之後的安裝時之接合特性良好乃 以形成（厚狀附加）厚度01 μηι以上之金覆膜較佳。 先前之Ni或Ni合金表面之鍍金方法中，一般已知有一種 方法，即首先藉由置換鍍金形成（薄狀附加）〇〇3〜〇〇5 薄的金覆膜，接著藉由還原鍍金形成期望厚度之金覆膜 (參照專利文獻1)。 另，專利文獻2中記載有一種置換無電解鍍金液，其含 有錯合劑、水溶性銀化合物，進而任意含有水溶性鉈化合 物、水溶性鉛化合物、水溶性銅化合物、水溶性鎳化合^ 或該等之組合。另，專利文獻2中記載有藉由置換鍍金薄 狀附加金覆膜後，使用相同鍍金液厚狀附加金覆膜。 再者，專利文獻3記载有一種置換無電解鑛金液其用 以薄狀附加金覆膜，以作為自催化型厚狀附加無電解鍍金 之底層，且薄狀附加作為底層之金覆膜後，為形成期望厚 度之金覆膜’進一步進行鍍金處理。 進而專利文獻4又揭示：爲了使鍍金中底層金屬侵蝕較 少，使鍍金覆膜與底層金屬之密接性上升，而使用添加有 聚乙烯亞胺之無電解鍍金液。 [專利文獻1]日本特開平6_232136號公報（1994年8月19 曰公開） [專利文獻2]國際公開第〇2/16668號手冊（2〇〇2年2月28 日公開） [專利文獻3]曰本特開平4_3 1487〇(ι 992年11月6日公開） [專利文獻4]曰本特開2〇〇3_13248(2〇〇3年1月15曰公開） 145326.doc 201033404 【發明内容】 [發明所欲解決之問題] 上述先前之鍍金方法中，以-次鍍金步驟所形成之金覆 膜之厚度為(U㈣以下，藉由鍍金對突起電極厚狀附如㈣ 厚度以上之金覆膜時’需要2次以上之鍍金步驟（進行薄狀 並 附加後再進行厚狀附加等）。據此有製造步驟繁雜化 且降低製造成本較困難之問題。[Technical Field] The present invention relates to a method of forming a bump electrode serving as a connection terminal of a semiconductor device, and a replacement gold plating solution. [Prior Art] Since the size of the transistor and the wiring of the semiconductor device is reduced, the degree of integration per unit area is increased, and thus the manufacturing cost is lowered. On the other hand, the functions of semiconductor devices are becoming large-scale and diverse. In the manufacturing cost of a semiconductor device, the cost of the step of manufacturing a semiconductor wafer (hereinafter referred to as the first half step) is greatly reduced. However, the cost of assembling the electronic component to the electronic circuit substrate (hereinafter referred to as the second half step) is almost the same. Not reduced. The cost in the latter half of the step tends to be a large proportion of the manufacturing cost of the semiconductor device, which is a major obstacle to the reduction in the manufacturing cost of the semiconductor device. In the semiconductor device for driving a liquid crystal panel, in addition to the strict low-cost requirements of the market, high-quality and multi-terminal is sought, and in this case, the cost of the second half of the process will account for more than half of the total. Moreover, in recent years, the price of precious metals has continued to rise. Therefore, it is formed in the liquid crystal panel drive: the bump electrode (hereinafter also referred to as a bump) of the semiconductor wafer in the conductor device is being converted from the former structure of the gold (Au) to the main structure of the bump. The Ministry is a non-precious metal 'only a new form of surface made of gold. As a method of forming the bump of such a new method, there is known a method of performing gold plating on the surface of the bump (the fourth) (Ni) alloy by using an electroless recording technique, which is advantageous for cost reduction. Method 145326.doc 201033404, the gold plating of the bumps is preferable for forming a gold film having a thickness of 01 μη or more in order to form a bonding property with good adhesion at the time of mounting. In the prior gold plating method of the Ni or Ni alloy surface, there is generally known a method of first forming a thin (thick addition) 〇〇3~〇〇5 thin gold film by displacement gold plating, followed by reduction gold plating. A gold film having a desired thickness (see Patent Document 1). Further, Patent Document 2 describes a replacement electroless gold plating solution containing a solvent and a water-soluble silver compound, and further containing a water-soluble cerium compound, a water-soluble lead compound, a water-soluble copper compound, a water-soluble nickel compound, or the like. A combination of the same. Further, in Patent Document 2, it is described that a gold film is added by a thin gold plating, and a gold film is added in the same thickness as the gold plating liquid. Further, Patent Document 3 discloses a replacement of an electroless gold concentrate for a thin gold-clad film, as an autocatalytic thick layer with an electroless gold plating underlayer, and a thin gold film as a bottom layer. Thereafter, a gold plating process for forming a gold film of a desired thickness is further performed. Further, Patent Document 4 discloses that an electroless gold plating solution to which a polyethyleneimine is added is used in order to increase the adhesion of the underlying metal to the underlying metal in order to increase the adhesion of the underlying metal in the gold plating. [Patent Document 1] Japanese Laid-Open Patent Publication No. Hei 6-232136 (published on August 19, 1994) [Patent Document 2] International Publication No. 2/16668 (published on February 28, 2002) [Patent Document 3曰 特 特 4 4 4 4 4 4 4 4 4 145 145 145 145 145 145 145 145 145 145 145 145 145 145 145 145 145 145 145 145 145 145 145 145 145 145 145 145 145 145 145 145 145 145 145 145 145 145 145 145 145 145 145 145 145 145 145 145 [Problem to be Solved by the Invention] In the above-described prior gold plating method, the thickness of the gold coating formed by the gold plating step is (U(4) or less, and the gold electrode is thicker than the (4) thickness of the protruding electrode by gold plating. In the case of a film, a gold plating step of two or more times is required (a thin shape is added and then added in a thick shape, etc.), whereby there are problems in that the manufacturing steps are complicated and the manufacturing cost is lowered.
本發明之目的係、提供-種突起電極之形成方法及置換鐘 金液，可只以-次置換Μ金步驟，即可對突起部之表面厚 狀附加具有良好接合特性之含金之膜（金膜），其結果，可 使製造步驟簡化、成本降低。 [解決問題之技術手段] 本發明之突起電極之形成方法，其特徵為：包含被覆步 驟，其使用含有亞硫酸鉀與聚乙烯亞胺或其衍生物之置換 鑛金液，在形成於電極上之導電性之突起部表面形成被覆 膜，一次上述被覆步驟中，在上述突起部表面形成厚度 0.1 μιη以上、0.5 μιη以下之被覆膜。 根據上述構成，由於使用含有亞硫酸鉀與聚乙烯亞胺或 其衍生物之置換鍍金液，被覆形成於電極上之導電性之突 起部表面，因此可在一次被覆步驟中，在上述突起部表面 形成厚度0.1 μιη以上、〇.5 μιη以下之具有良好接合特性之 被覆膜。即，可藉由一次被覆處理形成在形成突起電極上 充分膜厚之被覆膜，因此無需重複進行被覆處理。其結 果，可簡化突起電極之製造步驟，降低製造成本。 145326.doc 201033404 本發明之突起電極之形成方法中所形成之被覆膜在〇ι μιη以上，因此可以該膜完全被覆突起部，可將作為突起 電極之電阻值維持於低。另，本發明之突起電極之形成方 法中所开> 成之被覆膜在05 μιη以下，因此不僅具備作為突 起部之充分的功能，而且可降低製造成本。 本發明之突起電極之形成方法中所使用之置換鍍金液， 藉由含亞硫酸鉀，該亞硫酸鉀使金之析出速度上升，因此 可只以—次被覆步驟形成充分厚度之金膜。另，藉由置換 鍍金液進而含有聚乙烯亞胺或其衍生物，可形成外觀、接 合特性等優良之均一的金膜。因此’藉由僅一次被覆步驟 可於突起部之表面厚狀附加具有充分厚度，進而外觀優良 之均一的金膜。 另，本發明之突起電極之形成方法中，上述置換鍍金液 含有50 mg/L以上、500 mg/L以下之上述亞硫酸鉀較佳。 本發明之突起電極之形成方法中❹之置換鍵金液所含 有之亞硫酸鉀若在50 mg/L以上，則得到充分之鍍敷速 度，又若在500 mg/L以下，則電鍍液不會不穩定不會產 生自分解，因此可更穩定地形成對形成突起電極充分厚度 之金膜。 另 本發明之突起電極之形成方法令 含有0.01 mg/L以上、 衍生物較佳。 上述置換鍍金液 10 mg/L以下之上述聚乙烯亞胺或其 有 本發明之突起電極之形成方法中使用之置換鍍金液所含 之聚乙烯亞或其衍生物若在〇.〇1 mg/i^上，㈣覆之金 145326.doc -6 - 201033404 膜之外觀更良好 不會下降，進而 因此形成外觀、 容易。 ，又若在10 mg/L以下，則金之析出速度 不會引起突起部之表面與金之密著不良。 接合特性等更優良之均一的金膜進而變得 ❿ 另’較佳為，本發明之突起電極之形成方法中，上述置 換鐘金液進而含有作為金量之相當於G.l g/L以上、5·〇 g/L 以下之金鹽、10 g/L以上、7〇 g/L以下之亞硫酸鉀以外之 亞硫酸鹽、以及10 g/L以上、50 g/L以下之乙二胺四醋酸 鹽 本發明之突起電極之形成方法中所使用之置換鍍金液若 含有作為金量之相當於〇.〗g/L以上之金鹽，則可適度維持 金之析出速度，又若含有相當於5〇 g/L以下之金鹽，則可 更提高突起部表面與金之密著性。另，由於亞硫酸鹽具有 使金錯合物穩定之作用，因此本發明之突起電極之形成方 法中所使用之置換鐘金液，若除亞硫酸卸外含有亞硫酸鹽 φ 10 g/L以上，則金更穩定地存在，若亞硫酸鹽含70 g/L以 上，則金之析出速度不會下降，可維持高生產性。另，本 發明之突起電極之形成方法中所使用之置換鍍金液若含有 乙二胺四醋酸鹽，則被覆步驟中構成突起部之金屬溶出 時’可作為該金屬之錯合劑而發揮作用。若乙二胺四醋酸 鹽含10 g/L以上’則可使溶出之該金屬之影響減小，因此 可形成外觀更良好之鐘敷。另，若乙二胺四醋酸鹽之濃度 在50 g/L以下，則可以更低成本形成突起電極。 另’本發明之突起電極之形成方法中，上述置換鍵金液 145326.doc 201033404 在pH值6以上、pH值8以下，以及45°C以上、70°C以下較 佳。 本發明之突起電極之形成方法中所使用之置換鐘金液之 pH值若在6以上’則不會有置換鑛金液自分解之虞。另， 若pH值在8以下，則金之析出速度變高，可得到充分之鐘 敷速度。另，若使用之置換鍍金液在451以上之條件下使 用，則得到充分之鍍敷速度，可在短時間形成較佳厚度之 膜。另’若在7 0 C以下之條件下使用，則可降低置換鍵金 液自分解之可能性，因此可使該鍍敷液之穩定性上升。 義 本發明之置換鍍金液’其特徵為：其係用以在一次被覆 步驟中，在形成於電極上之導電性之突起部表面，形成厚 度〇·1 μηι以上、0·5 μηι以下之被覆膜者，且該置換鍍金液 含有亞硫酸鉀與聚乙烯亞胺或其衍生物。 本發明之置換鑛金液，由於係使用於用以在一次被覆步 驟中在形成於電極上之導電性之突起部表面，形成厚度 〇 · 1 μπι以上、〇. 5 μηι以下之被覆膜者，且含有亞硫酸卸與 聚乙烯亞胺或其衍生物，因此若將其用於突起電極之形 0 成，則可藉由一次被覆處理形成於形成突起電極上為充分 之臈厚且具有良好接合特性之被覆膜，無需重複進行被覆 處理。其結果，可簡化突起電極之製造步驟、降低製造成 本。 由於本發明之置換鑛金液含有亞硫酸鉀，因此藉由使金 之析出速度上升，可形成充分厚度之金膜。再者，由於本 發明之置換鍍金液含有聚乙烯亞胺或其衍生物，因此可形 145326.doc -8 - 201033404 成外觀、接合特性等優良之均一的金膜。 另’較佳為’本發明之一次被覆步驟中，用以形成厚度 在0.1 μιη以上、0.5 μπι以下之被覆膜之置換鍍金液，含5〇 mg/L以上、500 mg/L以下之上述亞硫酸鉀。 若本發明之置換鑛金液所含之亞硫酸鉀在50 mg/L以 上’則可得到充分之鍍敷速度，又若在50〇 mg/L以下，則 該鑛敷液不會不穩定，不會產生自分解，因此可更穩定地 形成需要充分厚度之金膜。 另’較佳為，本發明之一次被覆步驟中，用以形成厚度 〇·1 μπι以上、0.5 μπι以下之被覆膜之置換鍍金液，含有〇〇1 mg/L以上、1〇 mg/L以下之上述聚乙烯亞胺或其衍生物。 若本發明之置換鍍金液所含之聚乙烯亞胺或其衍生物在 〇.〇1 mg/L以上，則鍍金之外觀變得更良好，又若在1〇 mg/L 以下’則金之析出速度不會降低，進而不會引起突起部之 表面與金之密著不良。因此，形成外觀、接合特性等更優 良之均一的金膜進而變得容易。 另’較佳為，本發明之一次被覆步驟中，用以形成厚度 〇·1 μιη以上、0.5 μπι以下之被覆膜之置換鍍金液，進而含 有作為金篁之相當於〇.1 g/L以上、5 · 0 g/L以下之金鹽；1 〇 g/L以上、70 g/L以下之亞硫酸鹽；以及1〇 g/L以上、5〇 g/L以下之乙二胺四醋酸鹽。 若本發明之置換鍍金液含有作為金量之相當於〇.l g/L以 上之金鹽，則可適度地維持金之析出速度，又若含有相當 於5.0 g/L以下之金鹽’則可更提高突起部表面與金之密著 145326.doc -9- 201033404 性。另’由於亞硫酸鹽具有使金錯合物穩定之作用，因此 本發明之置換鐘金液若在亞硫酸鉀外含有亞硫酸鹽10 g/L 以上，則金更穩定地存在，若亞硫酸鹽含70 g/L以下，則 金之析出速度不會下降，可維持較高生產性。另，本發明 之置換鍍金液若含有乙二胺四醋酸鹽，則鍍金步驟中構成 突起部之金屬溶出時，可作為該金屬之錯合劑而發揮作 用。再者右本發明之置換錄金液含有1〇 g/L以上之乙二胺 四醋酸鹽’則可使溶出之該金屬之影響減小，因此可形成 外觀更良好之鍍敷。另，若乙二胺四醋酸鹽含5〇 g/La 下’則可以更低價形成鍍敷。 [發明之效果] 本發明之突起電極之形成方法由於如上所述包含被覆步 驟，其係在形成於電極上之導電性之突起部表面，使用含 有亞硫酸鉀與聚乙烯亞胺或其衍生物之置換鍍金液形成被 覆膜，且在一次上述被覆步驟中，在上述突起部表面形成 厚度0.1 μηι以上、0.5 μιη以下之被覆膜，因此可藉由一次 被覆處理形成於形成突起電極上為充分之膜厚，且具有良 好接合特性之被覆膜，因此無需重複進行被覆處理。其結 果’可簡化製造步驟、降低成本。 本發月之置換鑛金液，由於係用以在一次被覆步驟中， 在形成於電極上之導電性之突起部表面形成厚度〇i pm以 〇’5 μιη以下之被覆膜者，且含有亞硫酸針與聚乙烯亞 胺或其衍生物，因此若將其用於突起電極之形成，則可藉 由一次被覆處理形成於形成突起電極上充分膜厚之被覆 145326.doc 201033404 膜，無需重複進行被覆處理。其結果，可簡化突起電極之 製造步驟、降低製造成本。 【實施方式】 本發明之突起電極之形成方法具有被覆步驟，係使用含 亞硫酸鉀與聚乙稀亞胺或其衍生物之置換鍵金液，被覆形 成於電極上之導電性之突起部表面。本說明書中，突起電 極係指電性連接於電極之突起之電極，例如可以是設於半 Φ 導體裝置等之連接端子等，亦有稱作凸塊之情形。 針對本發明之突起電極之形成方法之一實施形態，參照 圖1(a)〜(c)如下進行說明，但本發明不限於該形態。圖 1(a)〜(c)係模式地顯示本發明之凸塊（突起電極之形成方 法之一實施形態之各步驟之剖面圖。 [核形成步驟] 首先，針對形成凸塊2之核（突起部）21之步驟（核形成步 驟）如下進行說明。再者，本實施形態中，雖說明在上述 • 被覆步驟前進行核形成步驟之例，但本發明中亦可另外準備 形成於電極12上之導電性之核21，再進行後述之被覆步驟。 形成核21之步驟中，首先如圖i(a)所示，準備在表面上 °又有電極12之基板1。電極12之不與基板1相接之面，以使 其一部分露出之方式藉由絕緣膜U被覆。基板1與電極12 亦可藉由接著劑等進行貼合。 作為基板1，只要為例如半導體裝置中通常使用之基板 即可’可較佳地使用矽基板、玻璃基板等。作為電極12， 只要為半導體裝置中通常使用之電極即可，可較佳地使用 145326.doc -11- 201033404 墊4之電極墊等。電極12可使用例如藉由鋁（Al)、銅 (Cu)、或鋁-矽合金（Ai_Si)、鋁銅合金（ai_Cu)、鋁矽銅 (A1KU)等之紹合金等所構成者。 接著，如圖1(b)所示，在電極12及絕緣膜丨丨上形成核 核21以具有導電性之金屬所構成，以電性連接於電極 I2之方式形成。 作為構成核21之金屬，使用藉由置換鑛金液鑛敷中與金 產生置換之金屬較佳，例如可舉出鎳（Ni)、鎳合金、錫 (Sn)、銅（〇〇等。若以該等金屬構成核21，則可在之後之 被覆步驟中有效率地進行鑛金。所形成之核2ι之形狀無特 別限定’但在凸塊與外部之料等連接之情形，可與該端 子連接之形狀較佳。 核21使用例如含有如鎳般之金屬之無電解鍍敷液，可藉 由在被覆膜11及電極12上析出該金屬而形成。形成包含以 錄為主要構成成份之核之情形，如後述之實施例所示首 先使鋅置換析出於設在碎基板之紹電極之表面（辞酸鹽處 理）。如此，藉由置換A1與鋅，在電極12表面生成=粒 子，可防止因A1過渡溶解，刈與沁之密著性下降。接著， 使用無電解鍍鎳液，將鎳析出至期望大小（或高产） 時’若藉由辞酸鹽處理在電極12表面生成辞㈣，則辞粒 子與Ni置換，接著Ni持續析出。其結果，可在電極Q表 高效形成由Ni所構成之突起部21。 再者’形成核21之方法不限於此，例如可使用眾知之· 微影技術，在基板1上藉由絕緣物形成欲形成核Η之部， 145326.doc 12 201033404 開口之掩膜圖案，使用眾知之電解鍍敷技術形成核21之方 法等。 [被覆步驟] 接著，如圖i(c)所示，進行在核21表面形成金膜（被覆膜）22 之被覆步驟。據此’可形成含有核21與金膜22之凸塊2。 被覆步驟中，使用含有亞硫酸鉀與聚乙烯亞胺或其衍生 物之本發明之置換鍍金液，以金膜22被覆核21之表面。被 φ 覆步驟中，使核21之表面與本發明之置換鍍金液接觸，藉 由置換鍍敷使金析出於核21之表面。置換鍍敷係無電解鍍 敷之一種’係使金屬從鍍敷液析出於被鍍敷面之方法。 作為使核21之表面與本發明之置換鍍金液接觸之方法， 例如可使用將核21之表面浸潰於置換鍍金液之方法；在核 21之表面噴射置換鍍金液之方法；及以與形成核21之基板 1正交之軸為中心使基板1旋轉，將置換鍍金液滴下於核21 之表面之方法等。 φ 本發明中’使用本發明之置換鍍金液置換鍍敷核21之情 形，核21藉由離子化傾向比金高之金屬構成較佳。例如藉 由鎳或鎳合金構成核21之情形，由於構成核21之金屬之離 子化傾向比金高’因此與置換鍍金液接觸時，其表面上構 成核21之金屬放出電子而溶解。其結果’鍍敷液中之金接 收該電子而析出於核21表面。據此，可在核21表面高效地 形成金膜22。 另，被覆步驟中，若使用本發明之置換鍍金液在核21表 面形成金膜22，則在一次被覆步驟中’可在核2 1之表面形 145326.doc -13- 201033404 成具有0.1 μηι以上、〇.5 μιη以下厚度之金膜。。即，本被 覆步驟中’藉由只進行一次使用上述置換鍍金液之置換鍍 金處理，可形成作為凸塊2之充分的金膜22，因此無需重 複如此置換鑛金處理而堆積膜。此處，若金膜22薄於(U _ 則有沒完全將核21表面被覆之虞，在無法完全被覆之情形 中作為凸塊2之電阻值會上升，故不佳。因此’作為金膜 22，（Μ _以上較佳，〇 2哗以上更佳。另，金膜η厚於 0.5 μηι之情形，由於會導致製造成本上升故不佳。可藉由 調節核21之表面與置換鑛金液接觸之時間，而調節金㈣〇 之厚度。因此，核21與置換鍍金液接觸之時間，可基於金 膜22之期望的厚度而設定。 [置換鍍金液] 此處，針對本發明之用以在形成於電極上之導電性之突 起部表面，在一次被覆步驟中形成厚度0.1 μιη以上、〇5 μηι以下之被覆膜之置換鍍金液（為說明方便，以下簡稱為 「本發明之置換鍍金液」）如下進行說明。本發明之置換 鍍金液，可使用於用以在形成於電極12上之核21之表面，❹ 在一次被覆步驟中形成厚度〇.! μιη以上、〇·5 _以下之金 膜22,且其含有亞硫酸鉀與聚乙烯亞胺或其衍生物。由於 本發明之置換鍍金液包含亞硫酸離子，因此亦有稱作亞硫 - 酸系置換鑛金液之情形。 ， 置換鍍金液係用以藉由置換鍍敷將被鍍敷物以金被覆之 鍍敷液，作為主要構成成份，係含有包含金之鹽、ρΗ值緩 衝劑及錯合劑者。置換鍍金液除上述外，亦可添加用以將 145326.doc -14· 201033404 析出之金之結晶改質，或促進析出速度之添加劑。置換鐘 金液無需如用以進行還原鍍金之鍍敷液（還原鍍金液）般， 包含藉由自催化作用使金析出之還原』，或抑制鍍敷液自 分解之穩定劑等，由於組合簡單因此調製容易，且可低成 本而調製。 另，還原鍍金液易產生液組成變化而不穩定，並且亦有 使金析出於凸塊表面以外之情形。與此相對，置換鑛金液 φ 與還原鍍金液相比較穩定，無需還原劑濃度之管理等，因 此具有管理容易之優點。 (亞硫酸鉀） 本發明之置換鍍金液所含之亞硫酸鉀之含量在5〇 以上、500 mg/L以下較佳。亞硫酸鉀雖具有使金之析出速 度提尚之作用，但若亞硫酸鉀少於5〇 mg/L，則有無法充 刀得到其效果之虞。又若多於5〇〇 mg/L ,則析出速度變 快，鍍敷液變得不穩定，有產生自分解之虞。因此，若是 • 前述之濃度，則將更容易地形成穩定且充分厚度之金膜 22»如此，由於本發明之置換錄金液含有亞硫酸鉀，因此 藉由析出之金被覆核21之表面後，亦持續使金析出，因此 可形成充分厚度之金膜22。 (聚乙稀亞胺或其衍生物） 本發明之置換鍍金液所含之聚乙烯亞胺只要是使乙烯亞 胺聚合之聚合物即可。例如作為此等聚乙烯亞胺，可使用 專利文獻4(曰本特開2003_13248)所記載之聚乙烯亞胺等。 另，聚乙烯亞胺亦可為其衍生物。 145326.doc -15- 201033404 另，本發明之置換鍍金液，含有聚乙烯亞胺或其衍生物 0.01 mg/L以上、10 mg/L以下較佳。若聚乙烯亞胺或其衍 生物之含有濃度少於〇 〇1 mg/L，則鍍敷之外觀帶有紅色， 進而變成粗的析出結晶，形成之凸塊之功能會產生問題。另 方面，若聚乙烯亞胺或其衍生物之含有濃度多於1〇 mg/L， 則金之析出速度下降，進而產生構成核21之金屬與金之密 著不良。另，聚乙烯亞胺或其衍生物具有將鑛敷之外觀調 整成擰檬黃色之作用。因此若使用本發明之置換鍍金液， 可形成外觀、接合特性等優良之均一的金膜22 ^ 0 本發明之置換鍍金液，可在形成於電極12上之核之表 面，在一次被覆步驟中形成厚度〇.! μιη以上、〇 5 μιη以下 金膜22即，右將本發明之置換鍍金液使用於凸塊2之 形成，則只藉由進行一次使用該置換鍍金液之置換鍍金處 理，可形成作為凸塊2之充分的金膜22，因此無需重複如 此置換錄金處理而堆積膜。 (金鹽） 另，本發明之置換鍍金液進而含有金鹽較佳。作為此等⑬ 金鹽雖無特別限定，但可舉出例如亞硫酸金鈉、亞硫酸金 鉀、亞硫酸金銨等。本發明之置換鍍金液，作為該鍍敷液 中之金量，較好含有相當於〇] g/L以上、5 〇 g/L以下之金鹽。 右金量少於0.1 g/L，則金之析出速度顯著減少，若多於5 〇 g/L，則有使構成突起部21之金屬與金之密著性下降之虞。 (亞硫酸鹽） 另，本發明之置換鍍金液進而含亞硫酸鉀以外之亞硫酸 145326.doc -16- 201033404 鹽較佳。作為亞硫酸鹽雖無特別限定，但可舉出例如亞硫 酸鈉、亞硫酸銨等。本發明之置換鍍金液除亞硫酸鉀外， 含10 g/L以上、70 g/L以下之亞硫酸鹽較佳。亞硫酸鹽具 有使金錯合物穩定之作用，若亞硫酸鹽少於1〇 g/L則金變 得不穩定而產生沉澱之虞，又若多於7〇 g/L則由於金過剩 變得穩定’因此金之析出速度下降，生產性下降。 (乙二胺四醋酸鹽） _ 另’本發明之置換鍍金液進而含乙二胺四醋酸鹽較佳。 作為乙二胺四醋酸鹽，可舉出乙二胺四醋酸、乙二胺四醋 酸二納、乙二胺四醋酸四納、乙二胺四醋酸三鉀等。本發 明之置換鑛金液含有1〇 g/L以上、5 0 g/L以下之乙二胺四 醋酸鹽較佳。若乙二胺四醋酸鹽少於1〇 g/L，則由於從核 21溶出之金屬之影響而外觀變差，若多於5〇 g/L，則材料 所需要之成本增加。乙二胺四醋酸鹽擔當被覆步驟中作為 從核21溶出之金屬離子之錯合劑之作用，與金屬離子結合 φ 形成錯合物，因而使金屬離子穩定化，藉此不會在鍍敷之 對象物上以外之場所使該金屬離子析出。因此可形成更良 好外觀之鍍敷。 本發明之置換鍍金液在45。〇〜7〇t之範圍使用較佳，更 加為55。(：左右。低於45°C之情形時無法得到充分之鍍敷速 度’用以形成較佳厚度之金膜22需要較長時間。另，超過 7〇t之情形時’置換鍍金液之穩定性劣化，有該鍍敷液產 生自分解之虞。 另’本發明之置換鍍金液以中性狀態使用較佳，進而以 145326.doc -17- 201033404 pH值6〜8之狀態使用較佳。pH值低於6之情形時，置換鍍 金液所含之錯合劑有可能氧化分解，進而有該鍍敷液自分 解之虞。另，pH值高於8之情形時，金之析出速度下降， 難以得到充分鍍敷速度之可能性較高。 本發明不限於上述實施形態，在請求項所示之範圍内可 進行各種變更。即，組合請求項所示範圍内進行適宜變更 之技術方式所得之實施形態亦包含於本發明之技術範圍。 [實施例] 本實施例中，首先根據核形成步驟，在設於形成於矽基 板上之半導體元件表面之鋁電極上，形成包含鎳之核。接 著，根據被覆步驟被覆金膜於核，形成凸塊。再者，對於 該凸塊之金膜評價膜厚、外觀及接合特性。 核形成步驟中，以無電解鍍敷在鋁電極上形成包含鎳之 核。首先，使用Merukuri-na-SC7001 (Meltex公司製）進行 脫脂後，使用Merupure-toFZ-7350(Meltex公司製）進行第1 鋅酸鹽處理。接著，使用30 vol%硝酸進行辞剝離後，使 用Merupure-toFBZ(Meltex公司製）進行第2鋅酸鹽處理，藉 由於鋁電極表面置換鋁與鋅而使鋅析出。再者，使用 Merupure-toNI 1869(Meltex公司製）進行30分鐘之無電解鐘 錄，形成10 μιη高度之核。 接著，在被覆步驟中對核實施鍍金，形成凸塊。在實施 例1及比較例1〜2中，使用下述表1所示之組成之置換鍍金 液，以pH值6.5、55°C實施30分鐘鍍金。 145326.doc •18· 201033404 [表l] 組成 實施例1 比較例1 比較例2 亞硫酸金納(金量） 1.5 g/L 1.5 g/L 1.5 g/L 乙二胺四醋酸二鈉 3〇g/L 30 g/L 30 g/L 乙二胺 2g/L 2g/L 2g/L 聚乙烯亞胺 2 mg/L 0 2 mg/L 亞硫酸鉀 200 mg/L 200 mg/L 0 pH值 6.5 6.5 6.5 另，被覆步驟中，比較例3係使用市售之無氰置換鍍金 液之 PuresyasufabuIG-7903(EEJA 公司製）’以 pH 值 6.0、 φ 60。(：實施30分鐘鍵金。比較例4中，使用PuresyasufabuIG-7903(EEJA公司製），以pH值6.0、60°C實施5分鐘置換鍍金 後，使用市售之無氰還原鍍金液之PuresyasufabuACG 3 000(EEJA公司製），以pH值7.5、65°C實施30分鐘還原鍍 金。再者，比較例3及4所使用之無氰置換鍍金液係不含聚 乙烯亞胺與亞硫酸鉀之置換鍍金液。 根據上述各步驟形成凸塊。各步驟顯示於下述表2。實 施例1及比較例1〜4中，以〇表示分別實施之步驟。 [表2] 步驟 實施例1 比較例1 比較例2 比較例3 比較例4 核形成 步驟 脫脂 〇 〇 〇 〇 〇 第1鋅酸鹽處理 〇 〇1 〇 〇 鋅剝離 〇 〇 〇 〇 〇 第2鋅酸鹽處理 〇 〇 〇 〇 〇 無電解鍍鎳 〇 〇 ~δ~ 〇 被覆 步驟 置換鍍金 〇 〇 〇 〇 〇 還原鍍金 無 無 無 無 〇 對於形成於所得之凸塊之金膜，評估膜厚及外觀。膜厚 之測定中，藉由聚焦離子束（FIB : Focused Ion Beam)切割 145326.doc •19- 201033404 凸塊之剖面，使用掃描式電子顯微鏡（SEM卜外觀之評估 乂目視進行，若為擰檬黃色、金屬光澤等則為「良好」， 若帶紅色、或褐色之情形則為「不良」。 另，針對所得之凸塊評估接合特性。首先，安裝形成凸 塊之基板作為半導體裝置。安裝時使用適於液晶面板驅動 用半導體裝置封裝之捲帶式封裝（Tape Carrier ， 使用TAB(Tape Aut〇mated B〇nding :捲帶式自動結合）之方 法。將形成凸塊之基板載置於形成接合端子（導線）之捲 帶，藉由進行加熱及加壓而接合，作為半導趙裝置進行安 裝。此時，實施於導線之鍍錫（Sn)覆膜與形成於凸塊之金 膜合金化，導線與凸塊接合。接合特性之評估，係對安裝 之半導體裝置之導線加入張力使之破斷，若其破斷部位在 導線與凸塊之界面以外則為「良好」，若在導線與凸塊之 界面則為「不良」。 表3顯示實施例1及比較例1〜4之評估結果。 [表3] 實施例1 比較例1 比較例2 比較例3 比較例4 膜厚（μιη) 0.30 0.34 0.09 0.04 0.30 外觀 良好 不良 良好 良好 良好 接合特性 良好 不良 不良 不良 良好 [實施例1] 實施例1中如上述形成凸塊，被覆步驟中如上述表1所 示’使用含1.5 g/L之亞硫酸金鈉（金量）、30 g/L之乙二胺 四醋酸二鈉、2 g/L之乙二胺、2 mg/L之聚乙烯亞胺以及 200 mg/L之亞硫酸鉀之置換鍍金液。 145326.doc -20- 201033404 形成於所得之凸塊之金膜之膜厚如上述表3所示，為 3〇 μηι，得到了充分厚度之金膜。另，金膜之外觀良 好為#檬黃色。並且接合特性良#，充份具備作為電極 - 所要求之特性。 • 再者，實施例1之金膜非常緻密，厚度之均一性高。 另：證明實施例1之置換鍍金液係可只以該鍍敷液而充分 形成具有厚度約〇.3 μηι之金膜者。 參 [比較例1] 比較例1中，置換鍍金液中不含聚乙烯亞胺之點與實施 例1不同，此外與實施例丨相同地進行。 形成於所得之凸塊之金膜之膜厚如上述表3所示，為 4 Pm，仵到了充分厚度之金膜。但金膜之外觀泛出紅 色，並且金膜之表面凹凸非常粗糙，為不適於接合之外 觀因此為外觀不良。並且接合特性亦不良。 [比較例2] 籲 &較例2中，置換鑛金液中不含亞硫酸鉀之點與實施 不同’此外與實施例1相同地進行。 形成於所得之凸塊之金膜之膜厚如上述表3所示，為 0.09 μιη’雖外觀良好’但無法得到充分厚度之金膜。其 結果’接合特性不良。 、 [比較例3] 比較例3中如上述形成凸塊’被覆步驟中使用不含聚乙 烤亞胺及亞硫酸鉀之置換鍍金液。 形成於所得之凸塊之金膜之膜厚如上述表3所示，為 145326.doc •21 · 201033404 骐之外觀雖良 0,04 μιη，無法得到充分厚度之金膜。金 好，但由於厚度較薄，因而接合特性不良。 [比較例4] 比較例4中如上述形成凸塊’被覆步驟中使用不含聚乙 烯亞胺及亞硫酸鉀之置換鍵金液進行置換鑛金後，進而實 施退原鑛金。 形成於所得之凸塊之金臈之膜厚如上述表3所示為 〇.〇3㈣，得到了充分厚度之金媒。並且金膜之外觀及接 合特性良好。 [產業上之可利用性] 由於本發明之突起電極之形成方法可簡化製造步驟、降 低成本，因此可較佳地利用於半導體裝置等之製造。 【圖式簡單說明】 圖1 (a)係模式地顯示本發明之凸塊之形成方法之一實施 形態中之一步驟之剖面圖； 圖1(b)係模式地顯示本發明之凸塊之形成方法之一實施 形態中之一步驟之剖面圖；及 圖1 (C)係模式地顯示本發明之凸塊之形成方法之一實施 形態中之一步驟之剖面圖。 【主要元件符號說明】 2 凸塊（突起電極） 12 電極 21 核（突起部） 22 金膜（被覆膜） 145326.doc •22·An object of the present invention is to provide a method for forming a bump electrode and a replacement bell gold liquid, which can be a gold-containing film having a good bonding property to a surface of a protrusion portion by a gold-plating step. As a result, the manufacturing steps can be simplified and the cost can be reduced. [Technical means for solving the problem] The method for forming a bump electrode of the present invention is characterized by comprising a coating step of forming a gold-containing solution containing potassium sulfite and polyethyleneimine or a derivative thereof on an electrode A coating film is formed on the surface of the conductive projection, and in the coating step, a coating film having a thickness of 0.1 μm or more and 0.5 μm or less is formed on the surface of the projection. According to the above configuration, since the surface of the conductive protrusion formed on the electrode is coated with a replacement gold plating solution containing potassium sulfite and polyethyleneimine or a derivative thereof, the surface of the protrusion can be applied in the primary coating step. A coating film having a bonding property of 0.1 μm or more and 〇5 μmη or less is formed. That is, since the coating film having a sufficient film thickness on the projection electrode can be formed by one coating treatment, it is not necessary to repeat the coating treatment. As a result, the manufacturing steps of the bump electrodes can be simplified, and the manufacturing cost can be reduced. 145326.doc 201033404 The coating film formed in the method for forming the bump electrode of the present invention is not less than 〇ι μηη, so that the film can be completely covered with the protrusion, and the resistance value as the bump electrode can be kept low. Further, in the method for forming a bump electrode of the present invention, the coating film is at most 5 μm, so that it has a sufficient function as a protruding portion and can reduce the manufacturing cost. In the replacement gold plating solution used in the method for forming the bump electrode of the present invention, since potassium sulfite is used, the potassium sulfite increases the rate of precipitation of gold, so that a gold film having a sufficient thickness can be formed only in the secondary coating step. Further, by replacing the gold plating solution and further containing polyethyleneimine or a derivative thereof, a uniform gold film excellent in appearance, bonding characteristics and the like can be formed. Therefore, a uniform gold film having a sufficient thickness and a good appearance can be added to the surface of the projection by a single coating step. Further, in the method for forming a bump electrode of the present invention, it is preferable that the replacement gold plating solution contains potassium sulfite of 50 mg/L or more and 500 mg/L or less. In the method for forming a bump electrode of the present invention, if the potassium sulfite contained in the gold-filled liquid of the hydrazine is 50 mg/L or more, a sufficient plating speed is obtained, and if it is 500 mg/L or less, the plating solution is not It is unstable and does not cause self-decomposition, so that a gold film having a sufficient thickness for forming the bump electrode can be formed more stably. Further, the method for forming the bump electrode of the present invention is preferably 0.01 mg/L or more, and the derivative is preferable. The polyethylene sublimine contained in the above-mentioned replacement gold plating solution of 10 mg/L or less or the polyethylene or its derivative contained in the replacement gold plating solution used in the method for forming the protruding electrode of the present invention is 〇.〇1 mg/ i^上, (4) Covering the gold 145326.doc -6 - 201033404 The appearance of the film is better without falling, and thus the appearance is easy. If it is below 10 mg/L, the precipitation rate of gold will not cause the surface of the protrusion to be inferior to the gold. In addition, in the method for forming a bump electrode of the present invention, the replacement bell gold liquid further contains Gl g/L or more as a gold amount, and 5 is preferable. · 金g/L or less gold salt, 10 g/L or more, 7 〇g/L or less of sulfite other than potassium sulfite, and 10 g/L or more, 50 g/L or less of ethylenediaminetetraacetic acid Salt If the gold plating solution used in the method for forming the bump electrode of the present invention contains a gold salt equivalent to 金.g/L or more as a gold amount, the gold deposition rate can be appropriately maintained, and if it contains 5 equivalents. The gold salt below 〇g/L can further improve the adhesion between the surface of the protrusion and the gold. Further, since the sulfite has an effect of stabilizing the gold complex, the replacement bell gold liquid used in the method for forming the bump electrode of the present invention contains sulfite φ 10 g/L or more in addition to the sulfuric acid. In addition, gold is more stably present. If the sulfite contains 70 g/L or more, the precipitation rate of gold does not decrease, and high productivity can be maintained. Further, when the replacement gold plating solution used in the method for forming the bump electrode of the present invention contains ethylenediaminetetraacetate, the metal constituting the protruding portion in the coating step can be used as a binder of the metal. If the ethylenediaminetetraacetate contains 10 g/L or more, the influence of the eluted metal can be reduced, so that a clock having a better appearance can be formed. Further, if the concentration of the ethylenediaminetetraacetate is 50 g/L or less, the bump electrode can be formed at a lower cost. Further, in the method for forming a bump electrode of the present invention, the replacement bond gold liquid 145326.doc 201033404 is preferably pH 6 or higher, pH 8 or lower, and 45 ° C or higher and 70 ° C or lower. When the pH value of the replacement bell gold liquid used in the method for forming the bump electrode of the present invention is 6 or more, the self-decomposition of the replacement mineral gold liquid does not occur. On the other hand, when the pH is 8 or less, the precipitation rate of gold becomes high, and a sufficient filling speed can be obtained. Further, if the replacement gold plating solution used is used under the conditions of 451 or more, a sufficient plating speed can be obtained, and a film having a preferable thickness can be formed in a short time. On the other hand, if it is used under the conditions of 70 ° C or lower, the possibility of self-decomposition of the replacement bond gold liquid can be lowered, so that the stability of the plating solution can be increased. The replacement gold plating solution of the present invention is characterized in that it is formed to have a thickness of 〇·1 μηι or more and 0·5 μηι or less on the surface of the conductive protrusion formed on the electrode in the primary coating step. The film is coated, and the replacement gold plating solution contains potassium sulfite and polyethyleneimine or a derivative thereof. The gold ore replacement liquid of the present invention is used for forming a film having a thickness of 〇·1 μπι or more and 〇. 5 μηι or less for use in the surface of the conductive protrusion formed on the electrode in the primary coating step. And containing sulfite and polyethyleneimine or a derivative thereof, if it is used for the shape of the bump electrode, it can be formed on the bump electrode by one-time coating treatment to be sufficiently thick and good. It is not necessary to repeat the coating process for the coating film of the bonding property. As a result, the manufacturing steps of the bump electrodes can be simplified, and the manufacturing cost can be reduced. Since the gold ore replacement liquid of the present invention contains potassium sulfite, a gold film having a sufficient thickness can be formed by increasing the rate of precipitation of gold. Further, since the displacement gold plating solution of the present invention contains polyethyleneimine or a derivative thereof, it is possible to form a uniform gold film which is excellent in appearance, bonding characteristics and the like, in the form of 145326.doc -8 - 201033404. Further, in the first coating step of the present invention, the replacement gold plating solution for forming a coating film having a thickness of 0.1 μm or more and 0.5 μm or less is contained in an amount of 5 〇 mg/L or more and 500 mg/L or less. Potassium sulfite. If the potassium sulfite contained in the replacement ore gold liquid of the present invention is 50 mg/L or more, a sufficient plating speed can be obtained, and if it is below 50 〇 mg/L, the ore solution is not unstable. Self-decomposition does not occur, so that a gold film requiring a sufficient thickness can be formed more stably. Further, it is preferable that the replacement gold plating solution for forming a coating film having a thickness of 〇·1 μπι or more and 0.5 μπι or less in the primary coating step of the present invention contains 〇〇1 mg/L or more and 1 〇mg/L. The above polyethyleneimine or a derivative thereof. When the polyethyleneimine or its derivative contained in the displacement gold plating solution of the present invention is at least 1 mg/L, the appearance of gold plating becomes better, and if it is below 1 〇mg/L, then The deposition rate is not lowered, and the surface of the protrusion is not damaged by the adhesion of gold. Therefore, it is easier to form a more uniform uniform gold film such as appearance and bonding characteristics. Further, in the primary coating step of the present invention, the replacement gold plating solution for forming a coating film having a thickness of 〇·1 μm or more and 0.5 μm or less is further contained as the equivalent of 篁.1 g/L. The above, a gold salt of 5 · 0 g / L or less; a sulfite of 1 〇 g / L or more, 70 g / L or less; and an ethylenediamine tetraacetic acid of 1 〇 g / L or more and 5 〇 g / L or less salt. When the gold plating solution of the present invention contains a gold salt equivalent to 〇.lg/L or more as a gold amount, the gold precipitation rate can be appropriately maintained, and if it contains a gold salt equivalent to 5.0 g/L or less, Improve the surface of the protrusion and the adhesion of gold 145326.doc -9- 201033404. In addition, since the sulfite has a function of stabilizing the gold complex, if the replacement bell gold liquid of the present invention contains 10 g/L or more of sulfite in addition to potassium sulfite, gold is more stably present, if sulfite When the salt content is 70 g/L or less, the precipitation rate of gold does not decrease, and high productivity can be maintained. Further, when the replacement gold plating solution of the present invention contains ethylenediaminetetraacetate, the metal constituting the projections in the gold plating step can be used as a binder of the metal. Further, in the case where the replacement gold liquid of the present invention contains 1 〇 g/L or more of ethylenediamine tetraacetate, the influence of the eluted metal can be reduced, so that a plating having a better appearance can be formed. In addition, if ethylenediaminetetraacetate contains 5 〇 g/La, then plating can be formed at a lower cost. [Effects of the Invention] The method for forming a bump electrode of the present invention includes a coating step as described above, which is based on the surface of the conductive protrusion formed on the electrode, and contains potassium sulfite and polyethyleneimine or a derivative thereof. The replacement gold plating solution forms a coating film, and in the above-described coating step, a coating film having a thickness of 0.1 μm or more and 0.5 μm or less is formed on the surface of the protrusion portion. Therefore, the coating film can be formed on the protrusion electrode by a single coating treatment. Since the film is sufficiently thick and has a good bonding property, it is not necessary to repeat the coating process. The result 'simplifies manufacturing steps and reduces costs. The replacement ore gold liquid of the present month is used to form a coating having a thickness 〇i pm of 〇'5 μm or less on the surface of the conductive protrusion formed on the electrode in the primary coating step, and contains Sulfite needle and polyethyleneimine or a derivative thereof, if it is used for the formation of a bump electrode, it can be formed by a single coating process on a film having a sufficient film thickness of 145326.doc 201033404 formed on the bump electrode without repeating Carry out the coating process. As a result, the manufacturing steps of the bump electrodes can be simplified, and the manufacturing cost can be reduced. [Embodiment] The method for forming a bump electrode of the present invention has a coating step of coating a surface of a conductive protrusion formed on an electrode by using a replacement gold liquid containing potassium sulfite and a polyethyleneimine or a derivative thereof. . In the present specification, the bump electrode refers to an electrode electrically connected to the bump of the electrode, and may be, for example, a connection terminal provided in a semi-Φ conductor device or the like, and may be referred to as a bump. An embodiment of the method for forming a bump electrode of the present invention will be described below with reference to Figs. 1(a) to 1(c), but the present invention is not limited to this embodiment. 1(a) to 1(c) are schematic cross-sectional views showing the steps of an embodiment of a method for forming a bump electrode of the present invention. [Nuclear formation step] First, for the core forming the bump 2 ( The step of the protrusion portion 21 (nuclear formation step) will be described below. In the present embodiment, an example in which the core formation step is performed before the above-described coating step is described. However, in the present invention, the electrode 12 may be separately prepared. The conductive core 21 is further subjected to a coating step to be described later. In the step of forming the core 21, first, as shown in Fig. i(a), the substrate 1 having the electrode 12 on the surface is prepared. The surface on which the substrate 1 is in contact with each other is exposed by the insulating film U. The substrate 1 and the electrode 12 may be bonded together by an adhesive or the like. The substrate 1 is generally used, for example, in a semiconductor device. For the substrate, a ruthenium substrate, a glass substrate, or the like can be preferably used. As the electrode 12, an electrode commonly used in a semiconductor device can be used, and an electrode pad of 145326.doc -11-201033404 pad 4 can be preferably used. Electrode 12 can be used For example, it is composed of aluminum (Al), copper (Cu), or aluminum-bismuth alloy (Ai_Si), aluminum-copper alloy (ai_Cu), aluminum beryllium copper (A1KU), etc. Next, as shown in Fig. 1 ( b), the core 12 is formed on the electrode 12 and the insulating film, and is made of a metal having conductivity, and is electrically connected to the electrode I2. As a metal constituting the core 21, a replacement mineral is used. The metal to be replaced with gold in the gold liquid ore is preferably, for example, nickel (Ni), a nickel alloy, tin (Sn), copper (such as ruthenium or the like. If the core 21 is formed of the metal, it may be thereafter In the coating step, the gold is efficiently carried out. The shape of the core 2 i formed is not particularly limited. However, in the case where the bump is connected to an external material or the like, the shape of the terminal can be preferably connected to the terminal. An electroless plating solution of a metal such as nickel can be formed by depositing the metal on the coating film 11 and the electrode 12. The formation of a core including the main constituent is recorded as shown in the following embodiment. First, the zinc is replaced by the surface of the electrode disposed on the broken substrate (acidate treatment). By replacing A1 with zinc and generating = particles on the surface of the electrode 12, it is possible to prevent the A1 transition from being dissolved, and the adhesion between the ruthenium and the ruthenium is lowered. Then, the electroless nickel plating solution is used to precipitate the nickel to a desired size (or In the case of high yield, when the word (4) is generated on the surface of the electrode 12 by the acid salt treatment, the particles are replaced with Ni, and Ni is continuously deposited. As a result, the protrusion 21 made of Ni can be efficiently formed on the electrode Q. Further, the method of forming the core 21 is not limited thereto. For example, the mask pattern to be formed by the insulator may be formed on the substrate 1 by using a well-known lithography technique, 145326.doc 12 201033404. A method of forming a core 21 by an electrolytic plating technique known in the art. [Covering Step] Next, as shown in FIG. 1(c), a coating step of forming a gold film (coating film) 22 on the surface of the core 21 is performed. According to this, the bump 2 containing the core 21 and the gold film 22 can be formed. In the coating step, the surface of the core 21 is coated with a gold film 22 using a displacement gold plating solution of the present invention containing potassium sulfite and polyethyleneimine or a derivative thereof. In the φ coating step, the surface of the core 21 is brought into contact with the displacement gold plating solution of the present invention, and the gold is deposited on the surface of the core 21 by displacement plating. Displacement plating is a type of electroless plating which is a method of depositing metal from a plating solution onto a surface to be plated. As a method of bringing the surface of the core 21 into contact with the replacement gold plating solution of the present invention, for example, a method of immersing the surface of the core 21 in the replacement gold plating solution; a method of spraying the displacement gold plating liquid on the surface of the core 21; The method in which the substrate 1 is perpendicular to the axis of the substrate 1 of the core 21, and the substrate 1 is rotated, and the gold plating is dropped on the surface of the core 21 is used. φ In the present invention, the replacement of the plating core 21 by the displacement gold plating liquid of the present invention is preferable, and the core 21 is preferably made of a metal having a higher ionization tendency than gold. For example, in the case where the core 21 is composed of nickel or a nickel alloy, since the metal constituting the core 21 has a higher ionization tendency than gold, the metal constituting the core 21 on the surface thereof emits electrons and dissolves when it contacts the displacement gold plating solution. As a result, gold in the plating solution receives the electrons and precipitates on the surface of the core 21. According to this, the gold film 22 can be efficiently formed on the surface of the core 21. Further, in the coating step, if the gold film 22 is formed on the surface of the core 21 by using the replacement gold plating solution of the present invention, the surface shape of the core 2 1 can be made to have a surface shape of 145326.doc -13 - 201033404 of 0.1 μηι or more in the primary coating step. , 〇.5 μιη thickness of the gold film. . In other words, in the coating step, the gold film 22 as the bump 2 can be formed by performing the replacement gold plating treatment using the above-mentioned replacement gold plating solution only once. Therefore, it is not necessary to repeat the gold ore replacement treatment to deposit the film. Here, if the gold film 22 is thinner than (U _, the surface of the core 21 is not completely covered, and the resistance value of the bump 2 rises when it is not completely covered, so it is not preferable. Therefore, 'as a gold film 22, (Μ _ above is better, 〇 2 哗 or more is better. In addition, the case where the gold film η is thicker than 0.5 μηι is poor because it causes an increase in manufacturing cost. It can be adjusted by adjusting the surface of the core 21 and the replacement mineral The thickness of the gold (4) 〇 is adjusted by the contact time of the liquid. Therefore, the time during which the core 21 is in contact with the replacement gold plating solution can be set based on the desired thickness of the gold film 22. [Replacement gold plating solution] Here, for the purpose of the present invention A replacement gold plating solution having a thickness of 0.1 μm or more and 〇5 μηι or less is formed in the surface of the conductive protrusion formed on the electrode in a single coating step (for convenience of explanation, hereinafter referred to as "the replacement of the present invention" The gold plating solution is described below. The replacement gold plating solution of the present invention can be used for forming a thickness 〇.! μιη or more, 〇·5 _ in the surface of the core 21 formed on the electrode 12. The following gold film 22, and Containing potassium sulfite and polyethyleneimine or a derivative thereof. Since the displacement gold plating solution of the present invention contains sulfite ions, there is also a case where it is called a sulfite-acid replacement mineral gold liquid. The plating solution in which the plated material is coated with gold by displacement plating is mainly composed of a gold salt, a pH value buffer, and a wrong agent. The replacement gold plating solution may be added in addition to the above. Modification of the crystal of gold precipitated by 145326.doc -14· 201033404, or an additive which promotes the rate of precipitation. The replacement bell gold liquid does not need to be used as a plating solution for reducing gold plating (reduction gold plating solution), including by autocatalysis The function of reducing the precipitation of gold, or the stabilizer for inhibiting the self-decomposition of the plating solution, is easy to prepare due to the simple combination, and can be prepared at a low cost. In addition, the reduction gold plating liquid is liable to cause liquid composition change and is unstable, and In contrast, the gold deposit φ is more stable than the reduced gold plating liquid phase, and it does not require the management of the reducing agent concentration, so it has management. Advantages of Easy (potassium sulfite) The content of potassium sulfite contained in the replacement gold plating solution of the present invention is preferably 5 Å or more and 500 mg/L or less. Although potassium sulfite has a function of increasing the precipitation rate of gold, However, if the potassium sulfite is less than 5 〇mg/L, there is a problem that the effect cannot be obtained by filling the knife. If it is more than 5 〇〇 mg/L, the precipitation speed becomes faster and the plating solution becomes unstable. The self-decomposing enthalpy is generated. Therefore, if the concentration is the above, it is easier to form a stable and sufficient thickness of the gold film 22». Since the replacement gold liquid of the present invention contains potassium sulfite, the gold is precipitated. After the surface of the core 21 is coated, gold is continuously deposited, so that a gold film 22 having a sufficient thickness can be formed. (Polyethyleneimine or a derivative thereof) The polyethyleneimine contained in the displacement gold plating solution of the present invention is as long as The polymer of ethyleneimine polymerization can be used. For example, as the polyethyleneimine, a polyethyleneimine or the like described in Patent Document 4 (Japanese Patent Laid-Open Publication No. 2003-13248) can be used. In addition, polyethyleneimine may also be a derivative thereof. Further, the replacement gold plating solution of the present invention preferably contains polyethyleneimine or a derivative thereof in an amount of 0.01 mg/L or more and 10 mg/L or less. If the concentration of the polyethyleneimine or its derivative is less than 〇1 mg/L, the appearance of the plating is red, which in turn becomes coarse precipitated crystals, and the function of the formed bumps causes problems. On the other hand, when the concentration of the polyethyleneimine or its derivative is more than 1 〇 mg/L, the precipitation rate of gold is lowered, and the adhesion between the metal constituting the core 21 and gold is poor. Further, polyethyleneimine or a derivative thereof has a function of adjusting the appearance of the mineral deposit to a lemon-yellow color. Therefore, if the gold plating solution of the present invention is used, a uniform gold film 22 0 can be formed which is excellent in appearance, bonding characteristics, etc., and the gold plating solution of the present invention can be formed on the surface of the core on the electrode 12 in the one-coating step. The thickness of the gold film 22 is formed by the thickness of the film 即. A sufficient gold film 22 as the bump 2 is formed, so that it is not necessary to repeat the gold plating process to deposit the film. (Gold Salt) Further, the replacement gold plating solution of the present invention further preferably contains a gold salt. The 13 gold salt is not particularly limited, and examples thereof include gold sodium sulfite, potassium sulfite, and gold ammonium sulfite. The gold plating solution of the present invention preferably contains a gold salt equivalent to 〇] g/L or more and 5 〇 g/L or less as the amount of gold in the plating solution. When the amount of right gold is less than 0.1 g/L, the precipitation rate of gold is remarkably reduced, and if it is more than 5 〇 g/L, the adhesion between the metal constituting the protrusion 21 and gold is lowered. (Sulphite) Further, the displacement gold plating solution of the present invention further contains sulfurous acid other than potassium sulfite 145326.doc -16 - 201033404 salt is preferred. The sulfite is not particularly limited, and examples thereof include sodium sulfite and ammonium sulfite. In addition to potassium sulfite, the displacement gold plating solution of the present invention preferably contains sulfites of 10 g/L or more and 70 g/L or less. Sulfite has the effect of stabilizing the gold complex. If the sulfite is less than 1〇g/L, the gold becomes unstable and precipitates, and if it is more than 7〇g/L, the gold is excessive. It has to be stable', so the rate of precipitation of gold has decreased and productivity has declined. (Ethylenediaminetetraacetate) _ Further The replacement gold plating solution of the present invention further preferably contains ethylenediaminetetraacetate. Examples of the ethylenediaminetetraacetate include ethylenediaminetetraacetic acid, ethylenediaminetetraacetic acid di-nanoate, ethylenediaminetetraacetic acid tetrasodium, and ethylenediaminetetraacetic acid tripotassium. The replacement mineral gold solution of the present invention preferably contains ethylene diamine tetraacetate of not less than 1 g/L and not more than 50 g/L. If the ethylenediaminetetraacetate is less than 1 〇 g/L, the appearance is deteriorated by the influence of the metal eluted from the core 21, and if it is more than 5 〇 g/L, the cost required for the material increases. The ethylenediaminetetraacetate acts as a complexing agent for the metal ions eluted from the core 21 in the coating step, and combines with the metal ions to form a complex compound, thereby stabilizing the metal ions, thereby not being the object of plating. The metal ions are precipitated in a place other than the object. Therefore, a plating with a better appearance can be formed. The displacement gold plating solution of the present invention is at 45. The range of 〇~7〇t is better, and it is 55. (: Left and right. When the temperature is lower than 45 °C, sufficient plating speed cannot be obtained.] It takes a long time to form the gold film 22 of a preferred thickness. In addition, when the temperature exceeds 7 〇t, the stability of the replacement gold plating solution is exceeded. The plating solution is degraded, and the plating solution of the present invention is preferably used in a neutral state, and further preferably used in a state of 145326.doc -17 - 201033404 pH of 6 to 8. When the pH value is lower than 6, the dislocation agent contained in the replacement gold plating solution may be oxidatively decomposed, and the plating solution may self-decompose. Further, when the pH value is higher than 8, the precipitation rate of gold is decreased. It is difficult to obtain a sufficient plating speed. The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the claims. The embodiment is also included in the technical scope of the present invention. [Embodiment] In the present embodiment, first, a core containing nickel is formed on an aluminum electrode provided on a surface of a semiconductor element formed on a germanium substrate in accordance with a core forming step. The gold film is coated on the core according to the coating step to form a bump. Further, the film thickness, the appearance, and the bonding property of the gold film of the bump are evaluated. In the core forming step, nickel is formed on the aluminum electrode by electroless plating. First, after degreasing using Merukuri-na-SC7001 (manufactured by Meltex Co., Ltd.), the first zincate treatment was carried out using Merupure-to FZ-7350 (manufactured by Meltex Co., Ltd.), and then, after peeling off with 30 vol% nitric acid, The second zincate treatment was carried out using Merupure-to-FBZ (manufactured by Meltex Co., Ltd.), and zinc was deposited by replacing aluminum and zinc on the surface of the aluminum electrode. Further, electroless electrolysis was carried out for 30 minutes using Merupure-to NI 1869 (manufactured by Meltex Co., Ltd.). The clock was formed to form a core having a height of 10 μm. Next, the core was subjected to gold plating to form a bump in the coating step. In Example 1 and Comparative Examples 1 to 2, a replacement gold plating solution having the composition shown in Table 1 below was used. Gold plating was performed for 30 minutes at pH 6.5 and 55 ° C. 145326.doc •18· 201033404 [Table 1] Composition Example 1 Comparative Example 1 Comparative Example 2 Gold sulphite (gold amount) 1.5 g/L 1.5 g/L 1.5 g/L disodium ethylenediaminetetraacetate 3 g/L 30 g/L 30 g/L Ethylenediamine 2g/L 2g/L 2g/L Polyethyleneimine 2 mg/L 0 2 mg/L Potassium sulfite 200 mg/L 200 mg/L 0 pH 6.5 6.5 6.5 In the coating step, Comparative Example 3 used a commercially available cyanide-free gold plating solution, Puresyasufabu IG-7903 (manufactured by EEJA Co., Ltd.) at pH 6.0 and φ 60. (: 30 minutes of gold bonding was carried out. In Comparative Example 4, Puresyasufabu IG-7903 (manufactured by EEJA Co., Ltd.) was used, and after 5 minutes of gold plating at pH 6.0 and 60 ° C, PuresyasufabuACG 3 was used as a commercially available cyanide-free reduction gold plating solution. 000 (manufactured by EEJA Co., Ltd.) was subjected to reduction gold plating at pH 7.5 and 65 ° C for 30 minutes. Further, the cyanide-free gold plating solution used in Comparative Examples 3 and 4 did not contain a replacement of polyethyleneimine and potassium sulfite. Gold plating liquid. The bumps were formed according to the above steps. The respective steps are shown in the following Table 2. In Example 1 and Comparative Examples 1 to 4, the steps were respectively performed by 〇. [Table 2] Step Example 1 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Nuclear formation step Degreasing 〇〇〇〇〇 1st zincate treatment 〇〇 1 〇〇 zinc stripping 〇〇〇〇〇 2nd zincate treatment 〇〇〇〇〇 electroless plating Nickel 〇〇~δ~ 〇 coating step replacement gold plating 〇〇〇〇〇 reduction gold plating without no flaws 〇 〇 For the gold film formed on the obtained bump, evaluate the film thickness and appearance. In the measurement of film thickness, by focusing ions Beam (FIB : Focused Ion Be Am) cutting 145326.doc •19- 201033404 The profile of the bump is determined by scanning electron microscopy (the evaluation of the appearance of the SEM, if it is a yellow, metallic luster, etc., if it is red, or In the case of brown, it is "bad." In addition, the bonding characteristics are evaluated for the obtained bumps. First, a bump-forming substrate is mounted as a semiconductor device, and a tape-and-reel package suitable for liquid crystal panel driving semiconductor device packaging is used for mounting ( Tape Carrier, using TAB (Tape Aut〇mated B〇nding), the substrate on which the bumps are formed is placed on a tape forming a joint terminal (wire) by heating and pressurizing The bonding is performed as a semiconductor device. At this time, the tin-plated (Sn) film applied to the wire is alloyed with the gold film formed on the bump, and the wire is bonded to the bump. The evaluation of the bonding property is performed on the mounting. The wire of the semiconductor device is broken by the tension, and if the broken portion is at the interface between the wire and the bump, it is "good", and if the interface between the wire and the bump is "bad" Table 3 shows the evaluation results of Example 1 and Comparative Examples 1 to 4. [Table 3] Example 1 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Film thickness (μιη) 0.30 0.34 0.09 0.04 0.30 Good appearance and good failure Good good bonding characteristics, good defects, good defects, good example [Example 1] In Example 1, the bumps were formed as described above, and in the coating step, as shown in Table 1 above, 'using 1.5 g/L of gold sodium sulfite (gold amount), Displacement gold plating solution of 30 g/L of disodium ethylenediaminetetraacetate, 2 g/L of ethylenediamine, 2 mg/L of polyethyleneimine, and 200 mg/L of potassium sulfite. 145326.doc -20- 201033404 The film thickness of the gold film formed on the obtained bump is 3 〇 μηι as shown in Table 3 above, and a gold film having a sufficient thickness is obtained. In addition, the appearance of the gold film is good as #檬黄. Moreover, the bonding characteristics are good, and the characteristics required as the electrode are sufficient. • Further, the gold film of Example 1 is very dense and has a high uniformity of thickness. Further, it was confirmed that the displacement gold plating liquid of Example 1 can sufficiently form a gold film having a thickness of about 0.3 μm by using only the plating liquid. [Comparative Example 1] In Comparative Example 1, the point in which the polyethyleneimine was not contained in the replacement gold plating solution was different from that in Example 1, and the same procedure as in Example 1 was carried out. The film thickness of the gold film formed on the obtained bump was 4 Pm as shown in the above Table 3, and a gold film having a sufficient thickness was obtained. However, the appearance of the gold film is red, and the surface of the gold film is very rough, which is unsuitable for bonding and is therefore poor in appearance. And the joint characteristics are also poor. [Comparative Example 2] In Comparative Example 2, the point at which the potassium sulfite was not contained in the replacement ore gold liquid was different from that of the embodiment, and the same procedure as in Example 1 was carried out. The film thickness of the gold film formed on the obtained bump was as shown in the above Table 3, and the appearance was good as 0.09 μηη, but a gold film having a sufficient thickness could not be obtained. As a result, the bonding characteristics were poor. [Comparative Example 3] In Comparative Example 3, a replacement gold plating solution containing no polyethyleneimine and potassium sulfite was used as described above in the step of forming a bump. The film thickness of the gold film formed on the obtained bump was as shown in the above Table 3, and it was 145326.doc •21 · 201033404. Although the appearance was good, 0,04 μm, a gold film having a sufficient thickness could not be obtained. Gold is good, but the bonding properties are poor due to the thin thickness. [Comparative Example 4] In Comparative Example 4, in the step of forming the bumps described above, the gold ore was replaced with a gold-containing liquid containing no substitution of polyethyleneimine and potassium sulfite, and then the ore-removing gold was further carried out. The film thickness of the gold iridium formed on the obtained bump was as shown in Table 3 above, 〇.〇3(4), and a gold medium having a sufficient thickness was obtained. Moreover, the appearance and bonding characteristics of the gold film are good. [Industrial Applicability] Since the method of forming the bump electrode of the present invention can simplify the manufacturing steps and reduce the cost, it can be preferably used for the manufacture of a semiconductor device or the like. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1(a) is a cross-sectional view showing one step of an embodiment of a method for forming a bump of the present invention; FIG. 1(b) is a view schematically showing a bump of the present invention. A cross-sectional view showing one of the steps in the embodiment; and (C) is a cross-sectional view showing one of the steps in the embodiment of the method for forming the bump of the present invention. [Description of main component symbols] 2 Bump (protrusion electrode) 12 Electrode 21 Nucleus (protrusion) 22 Gold film (coated film) 145326.doc •22·