經濟部中央標準局貝工消费合作社印11 五、發明説明（ t明背景 本發明係關於一種蝕刻矽晶圓之方法。更明確言之，本 發明係關於一種蝕刻矽晶圓之方法，其可獲得矽晶圓之安 定表面 0 在矽晶圓製程中’特別是蝕刻步驟，已成爲在移除矽晶 圓表面上之傷害且同時保持矽晶圓表面平坦形狀之觀點上 <一個重要步驅。蝕刻步驟係在研磨步驟後及抛光步驟前 尤其疋，當半導體裝置之微〜細性改進時，對於矽晶圓平 坦性之要求條件雙得更嚴格。僅藉由控制拋光步驟，難以 改良矽晶圓之平坦性，還需要蝕刻步驟中之精密處理，其 對於矽晶圓之表面形狀有影嚮。爲滿足此種要求條件，不 僅是蝕刻液體之組成，而且是蝕刻裝置本身均已於最近經 改良。 但是，由於蝕刻步驟之目的係爲侵蝕矽晶圓之表面，鑒 於矽之性質，故氧化薄膜並不足以立即在蝕刻後所獲得之 矽晶圓表面上形成，且矽晶圓之表面顯示疏水性。 ί尤在蝕刻後，使矽晶圓接受沖洗處理，以抑制蝕刻之進 展。對沖洗處理而言，於習用上已使用去離子水。由於去 離.子水未具有氧化能力.，故發晶圓表面之疏水性仍保持著 。在此種情況中，矽晶圓表面係被活化，且因此外源物質 易於黏附至矽晶圓表面。再者，一旦外源物質黏附，該外 源物質係直接與矽晶圓接觸，於是在隨後洗滌步驟或其類 似步驟中’於移除外源物質上有困難D再者，當沖洗不足 或當隨後乾燥不充分時，沖洗液會以水滴形式黏附至矽晶 -4- 卜紙張尺度適用中國國家標準（CNS ) Λ4規格（210 X297公楚 ---.--.-----裝------訂------<〆 (請先閱讀背面之注意事項再填寫本頁) a? 4〇8^36弓 --—______ ____Β7 五、發明説明（2 ) ~ 圓疋疏水性表面上。若此情況保持著，則在♦晶圓自然乾 燥後，微量水滴會留下而成爲水斑。 水斑不只疋微量去離子水而已。水滴會吸收空氣中之氧 且係部伤而異常地氧化，故水斑不能夠在隨後洗滌步驟 中使用APM液體（意即，經由以肖去離+水稀㈣與過氧 化氫所製成之洗滌液體）移除。此種缺陷經常不僅在矽晶 圓製程中，而且在半導體裝置處理中造成。 發明摘沭 -在考量此種習用問題下’本發明之目的係爲提供一種蝕 ’J夕曰9圓之方法，此方法能夠預先避免缺陷在蚀刻處理期 間發生。一 根據本發明，係提供—種蝕刻矽晶圓之方法，其包括以 下步驟： 研磨矽晶圓； 蝕刻矽晶圓；及 抛光矽晶圓； 其中蝕刻步驟包括蝕刻處理與沖洗處理，並將至少一種 經濟部中央橾準局貝工消資合作社印製 氧化劑加入欲被用於沖洗處理之沖洗液中，於是在矽晶圓 表面上形成氧化薄膜。 由於將,氧化劑，譬如臭氧，中和劑及表面活性劑或潤濕 劑加入欲被用於抑制蝕刻之沖洗液中，故矽晶圓表面係在 沖洗處理期間被氧化，於是藉安定氧化薄膜保護矽晶圓表 面’以致能夠避免缺陷發生。 附圖簡述 ------5- 本紙張尺度適用中國國家標準（CNS ) A4規格（2i〇x297公釐） 408384 Αν __________B7 五、發明説明（3 ) ~一 ' 圖1爲一示意圖，説明在本發明蝕刻矽晶圓方法及習用 蚀刻砂晶圓方法中之外來物質黏附之情況。 圖2爲一圖表，説明在用於沖洗處理之沖洗液中添加臭 氧之作用。 鼓#具體實施例之詳诚 本發明係詳細地描述於下文。 首先，係一般性地描述一種製造矽晶圓之方法。使由矽 單晶所組成之矽鑄錠接受切片_、研磨、蝕刻、抛光及洗滌 ，依此順序進行、，以獲得矽晶圓作爲產物。然後，將矽晶 圓轉移至半導體裝置之製程 蝕刻步驟-係由蝕刻處理及抑制蝕刻之沖洗處理所構成。 在研磨矽晶圓後，由於漿液或其類似物所賦予之傷害，仍 留在矽晶圓表面上。蝕刻矽晶圓係爲移除表面上之傷害。 詳3之’在蝕刻步驟中係使用含有氟化氫^^)、硝酸（册〇3) 、醋鉍（CH3 COOH)及水之混合酸，以移除受傷害之矽晶圓 表面層。 沖洗處理係在蝕刻處理後進行。對沖洗處理係經常施加 快速潮濕冲洗、溢流沖洗或其類似方式。在快速潮濕沖洗 經濟部中央梂準局男工消費合作社印家 ------.----i------ir (請先閲讀背面之注意事項再填寫本頁) 中，供應與排放去離子水之循環，係重複數次。在溢流沖 洗中，係從容器底邵供應去離子水至含有矽晶圓之容器中 歷經一段預定時間，以致使去離子水溢流，及同時移除 砂晶圓上之酸。 於本發明中，係在前逑沖洗處理中，將至少—種氧化劑 ，#如臭氧，加入用於抑制蝕刻之沖洗液中，以在矽晶 _______ -6- 本紙張尺度適用中國國家梯芈（CNs7X^iJ72T0^^i7 A7 408384 五、發明説明（4 ) .--.-----^------II (請先閱讀背面之注意事項再填寫本I) 表面上形成氧化薄膜。此外，較佳係將中和劑加入沖洗液 中’以停止蚀刻反應’及較佳係添加表面活性劑或潤濕劑 以儘可能大爲減少矽晶圓表面上之污染。 在蝕刻步驟中用於沖洗處理之氧化劑並不受限，且臭氧 ，過氧化氫’氫氧化銨與過氧化氫之混合物，確酸及硫酸 或其類似物，均可使用。 雖然氧㈣，譬如以0.5至4〇ppm範圍之速率溶解在去離 子水中之臭氧是有效的，但I經濟觀點，此速率較佳係在 2至20Ppin之範園-内。有各種已知方法用以產生臭氧，且任 何方法均可採用。沖洗處理用之溫度亦無限制。 順便指出、欲被加入沖洗液中之中和劑、表面活性劑及 潤濕劑，並未有特別限制’ 1已知藥劑均可作爲此藥劑採 用。 本發明係以圖中所示之具體實施例爲基礎，更詳細地描 述於下文。 圖1爲一不意圖，説明在本發明蝕刻矽晶圓方法與習用 蝕刻矽晶圓方法中之外來物質黏附之情況。參考數字^係 表示矽晶圓。圖1之（a)係顯示矽晶圓在剛切離矽鑄錠後之 經濟部中央標準局貝工消费合作社印製 狀態。圖1之⑻係顯示矽晶圓在圖1(a)中所示之矽晶圓丄表 面上之傷害被移除後之狀態。 -圖！之（〇係顯示沖洗處理後所獲得之矽晶圓1之表面狀態 。其中之一顯7JT在僅使用去離子水沖洗處理後，無氧化薄 膜。另一個則顯示有氧化薄膜2存在，在使用*離子水！且 其中具有氧化劑譬如臭氧之沖洗處理後，於石夕晶圓表面上 ______-7- 本紙狀^賴㈣财料（CNS ) ΛϋΤΐΤ〇 X 29;公楚 Λ7 B7 408384 五、發明説明（5 ) 形成。 圖1之（d)顯示污染物3壁：4 At |， 紐各 未物3警如外來物質黏附之情況，其係於Printed by the Central Standards Bureau of the Ministry of Economic Affairs, Shellfish Consumer Cooperatives 11 V. INTRODUCTION TO THE INVENTION The present invention relates to a method for etching silicon wafers. More specifically, the present invention relates to a method for etching silicon wafers. Obtaining a stable surface of a silicon wafer 0 In the silicon wafer process, especially the etching step, it has become an important step driver from the viewpoint of removing damage on the surface of the silicon wafer while maintaining the flat shape of the silicon wafer surface The etching step is particularly fragile after the polishing step and before the polishing step. When the micro-fineness of the semiconductor device is improved, the requirements for the flatness of the silicon wafer are more stringent. It is difficult to improve the silicon only by controlling the polishing step The flatness of the wafer also requires precise processing in the etching step, which has an impact on the surface shape of the silicon wafer. To meet this requirement, not only the composition of the etching liquid, but also the etching device itself have recently been However, since the purpose of the etching step is to erode the surface of the silicon wafer, in view of the nature of silicon, it is not sufficient to oxidize the film immediately after etching. The obtained silicon wafer is formed on the surface, and the surface of the silicon wafer shows hydrophobicity. In particular, after the etching, the silicon wafer is subjected to a rinsing process to suppress the progress of the etching. For the rinsing process, it has been used in conventional applications. Deionized water. Since the deionized water does not have the ability to oxidize, the hydrophobicity of the surface of the wafer is still maintained. In this case, the surface of the silicon wafer is activated, and therefore foreign materials are liable to adhere to The surface of the silicon wafer. Moreover, once the foreign material is adhered, the foreign material is in direct contact with the silicon wafer, so it is difficult to remove the foreign material in the subsequent washing step or the like. Furthermore, When the rinse is insufficient or when the subsequent drying is not sufficient, the rinse solution will adhere to the silicon crystal in the form of water droplets. -4- Paper size applies to Chinese National Standard (CNS) Λ4 specification (210 X297 Gongchu ---.--.--) --- Installation ------ Order ------ < 〆 (Please read the notes on the back before filling in this page) a? 4〇8 ^ 36 弓 --——______ ____ Β7 V. Description of the invention (2) ~ On the hydrophobic surface of the cymbal. If this condition is maintained, after the wafer is naturally dried, Water droplets will remain and become water spots. Water spots are not only a trace of deionized water. Water droplets will absorb oxygen in the air and cause injuries to the part and abnormal oxidation, so water spots cannot use APM liquid in subsequent washing steps ( In other words, it is removed through the washing liquid made with Xiao deionization + water diluent and hydrogen peroxide. This kind of defect is often caused not only in the silicon wafer process but also in the semiconductor device processing. Invention Abstract- In consideration of such conventional problems, the purpose of the present invention is to provide a method for etching 9 circles, which can prevent defects from occurring during the etching process in advance. According to the present invention, it provides a kind of etching silicon crystal The round method includes the following steps: grinding a silicon wafer; etching a silicon wafer; and polishing a silicon wafer; wherein the etching step includes an etching process and a flushing process, and transforms at least one of the Central Ministry of Economic Affairs, the Central Bureau of Standards, and the Baygong Consumer Cooperative The printed oxidant is added to the rinsing solution to be used in the rinsing process, so that an oxide film is formed on the surface of the silicon wafer. Since oxidants, such as ozone, neutralizers and surfactants or wetting agents, are added to the rinse solution to be used to suppress etching, the surface of the silicon wafer is oxidized during the rinse process, so it is protected by a stable oxidation film. The surface of the silicon wafer 'is such that defects can be avoided. Brief description of the drawings ------ 5- This paper size is applicable to the Chinese National Standard (CNS) A4 specification (2i0x297 mm) 408384 Αν __________B7 V. Description of the invention (3) ~ a 'Figure 1 is a schematic diagram, The situation of the adhesion of foreign substances in the method for etching a silicon wafer and the conventional method for etching a sand wafer according to the present invention will be described. Fig. 2 is a diagram illustrating the effect of adding ozone to the rinsing liquid used for the rinsing treatment. Drum #Detailed Examples The present invention is described in detail below. First, a method for manufacturing a silicon wafer is generally described. The silicon ingot composed of silicon single crystals is subjected to slicing, grinding, etching, polishing, and washing in this order to obtain a silicon wafer as a product. Then, the process of transferring the silicon wafers to the semiconductor device. The etching step is composed of an etching process and a flushing process to suppress the etching. After grinding the silicon wafer, it remains on the surface of the silicon wafer due to the damage caused by the slurry or the like. Etching silicon wafers removes damage from the surface. In detail 3 ′, in the etching step, a mixed acid containing hydrogen fluoride (^^), nitric acid (Book 03), bismuth acetate (CH3 COOH), and water is used to remove the damaged silicon wafer surface layer. The rinsing process is performed after the etching process. Rinse treatment systems are often subjected to rapid wet flushing, overflow flushing, or the like. In the fast-humidity flushing of the printing house of the Central Workers' Union of the Ministry of Economic Affairs, Male Workers Consumer Cooperatives, ------------------------ (Please read the precautions on the back before filling this page), The cycle of supplying and discharging deionized water is repeated several times. In overflow flushing, the deionized water is supplied from the bottom of the container to the container containing the silicon wafer for a predetermined period of time, so that the deionized water overflows and the acid on the sand wafer is removed at the same time. In the present invention, at least one kind of oxidizing agent, such as ozone, is added to the washing liquid for inhibiting the etching in the front rinsing treatment, so that the silicon crystal _______ -6- This paper standard is applicable to the Chinese national ladder. (CNs7X ^ iJ72T0 ^^ i7 A7 408384 V. Description of the invention (4) .--.----- ^ ------ II (Please read the notes on the back before filling in this I) Oxidation on the surface In addition, it is preferred to add a neutralizing agent to the rinse solution to 'stop the etching reaction' and preferably add a surfactant or wetting agent to minimize contamination on the surface of the silicon wafer. In the etching step The oxidizing agent used in the washing process is not limited, and ozone, hydrogen peroxide, a mixture of ammonium hydroxide and hydrogen peroxide, acid and sulfuric acid or the like can be used. Although the oxygen is, for example, 0.5 to A rate in the range of 40 ppm is effective for dissolving ozone in deionized water, but from an economic point of view, this rate is preferably within the range of 2 to 20 Ppin. There are various known methods for generating ozone, and any method Both can be used. There is no restriction on the temperature used for the rinse treatment. 2. Neutralizers, surfactants and wetting agents to be added to the rinsing liquid are not particularly limited. 1 Known agents can be used as this agent. The present invention is based on the specific examples shown in the drawings. The basics are described in more detail below. Figure 1 is an intent, illustrating the situation of foreign matter adhesion in the method of etching silicon wafers and the conventional method of etching silicon wafers according to the present invention. Reference numerals ^ indicate silicon wafers. Figure 1 (a) shows the printing status of the silicon wafer immediately after being cut from the silicon ingot by the Central Standards Bureau Shellfish Consumer Cooperative of the Ministry of Economic Affairs. Figure 1 shows the silicon wafer as shown in Figure 1 (a). The state after the damage on the surface of the silicon wafer was removed. -Figure! (0 shows the surface state of the silicon wafer 1 obtained after the rinse process. One of them showed that 7JT was rinsed with deionized water only After processing, there is no oxidized film. The other shows the presence of oxidized film 2 when using * ionized water! And the oxidizing agent such as ozone is rinsed on the surface of the Shixi wafer. ㈣ 财 料 (CNS) ΛϋΤΐΤ〇X 29; Gongchu Λ7 B7 408384 5. The description of the invention (5) is formed. Figure 1 (d) shows the wall of the pollutant 3: 4 At |
儲存期間黏附至矽晶圓1。4设，+ L 3圃1右僅使用去離子水沖洗，則污 染物3及其類似物會直接黏附至矽晶圓i。 圖2説明沖洗處理之作限 ^ I作用，其中係將臭氧加入沖洗液中 〇 正如伙圖2中所不（結果所顯見者，在沖洗液中使用臭 氧之沖洗處理，在與值使用去離子水之沖洗處理比較下， _會減少砂晶圓中 ''缺陷之發生。 順便U ’缺陷率係在光凝聚條件下，藉由目視檢查石夕 晶圓表面而一獲得。 如前述：根據本發明’缺陷在碎晶圓表面上之發生係受 限制，因爲氧化薄膜係藉由添加氧化劑譬如臭氧至欲被用 於沖洗處理之沖^夜巾，而於矽晶圓表面上形A;於是顯 不改良半導體裝置、良率或其類似性質之値得注意之作用 〇 鑒於上述，可明瞭已達成本發明之數項目的，並獲得其 他有利結果。 由於在未偏離本發明之範園下，各種改變可於上述方法 '中施行，故所有包含在上述説明中及顯示在附圖中之事項 ，均將解釋爲説明性而非限制意義。 本紙張尺度·中_家榇準 ---.--.----^------1Τ------yA. (#先聞讀背面之注意事項再填寫本頁) 經濟部中央標準局員工消費合作社印製 8During storage, it is adhered to silicon wafer 1.4, + L 3 and 1 are rinsed with deionized water only, and pollutant 3 and the like will adhere directly to silicon wafer i. Fig. 2 illustrates the limitation of the rinsing treatment, which is the addition of ozone to the rinsing solution. As shown in Fig. 2 (see the results, the rinsing treatment using ozone in the rinsing solution, and deionization in the same value). Under the comparison of water rinse treatment, _ will reduce the occurrence of `` defects in sand wafers. By the way, U 'defect rate is obtained by visually inspecting the surface of Shi Xi wafer under photocoagulation conditions. As mentioned previously: According to this The invention's occurrence of defects on the surface of broken wafers is limited, because the oxidized film is formed on the surface of the silicon wafer by adding an oxidizing agent such as ozone to the night towel that is to be used for processing. The effect of not paying attention to improving the semiconductor device, the yield rate or the like. In view of the above, it is clear that the number of items that have reached the cost of the invention, and other advantageous results are obtained. Changes can be implemented in the above method, so all matters included in the above description and shown in the drawings will be interpreted as illustrative rather than limiting. This paper standard · 中 _ 家 榇 准 --- .--.---- ^ ------ 1Τ ------ yA. (#First read the notes on the back before filling out this page) Printed by the Staff Consumer Cooperative of the Central Standards Bureau of the Ministry of Economic Affairs 8