JPH0147004B2 - - Google Patents
Info
- Publication number
- JPH0147004B2 JPH0147004B2 JP54161197A JP16119779A JPH0147004B2 JP H0147004 B2 JPH0147004 B2 JP H0147004B2 JP 54161197 A JP54161197 A JP 54161197A JP 16119779 A JP16119779 A JP 16119779A JP H0147004 B2 JPH0147004 B2 JP H0147004B2
- Authority
- JP
- Japan
- Prior art keywords
- metal
- layer
- semiconductor substrate
- alloy layer
- semiconductor
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10P—GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10
- H10P30/00—Ion implantation into wafers, substrates or parts of devices
- H10P30/20—Ion implantation into wafers, substrates or parts of devices into semiconductor materials, e.g. for doping
Landscapes
- Solid-Phase Diffusion Into Metallic Material Surfaces (AREA)
- Other Surface Treatments For Metallic Materials (AREA)
- Electrodes Of Semiconductors (AREA)
- Internal Circuitry In Semiconductor Integrated Circuit Devices (AREA)
Description
【発明の詳細な説明】
本発明は、半導体基体への金属拡散に適した金
属拡散方法に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a metal diffusion method suitable for metal diffusion into a semiconductor substrate.
従来、例えばスイツチング用トランジスタ等に
於てのライフタイムキラーとして金（Au）等が
使用われる。通常はPN接合を作り終つた半導体
基板の裏面にライフタイムキラーとなる金属、例
えばAuを蒸着してのち熱拡散するが、その際蒸
着でのAuの量はライフタイムキラーとして使わ
れるAuの量よりはるかに多く、素子に悪影響を
与える。 Conventionally, gold (Au) or the like has been used as a lifetime killer in, for example, switching transistors. Normally, a lifetime killer metal such as Au is vapor-deposited on the back side of a semiconductor substrate after forming a PN junction, and then thermally diffused.In this case, the amount of Au used during vapor deposition is the amount of Au used as a lifetime killer. much more than that, and has a negative effect on the device.
本発明は、上述の点に鑑み、常に一定の金属の
拡散量が得られる金属拡散方法を提供するもので
ある。 In view of the above-mentioned points, the present invention provides a metal diffusion method that can always obtain a constant amount of metal diffusion.
本発明においては、半導体基体の一主面にイオ
ンビームを照射し、該主面を非晶質化して後、基
体主面上に金属層を蒸着等によつて形成し、金属
層上にレーザ光を照射して金属−半導体の合金層
を形成し、合金化されずに残つた金属層を選択的
に除去して後、熱処理により合金層を拡散源にし
て半導体基体に金属を拡散させるようになす。こ
の方法によれば、イオンビームの照射によつて半
導体基体の表面が非晶質化されることにより、基
体表面に金属層を形成し金属層のレーザ光を照射
したとき、基体表面の熱吸収が良いためにレーザ
スポツト内でのレーザ強度の強弱の差があつても
熱伝導によりその差がなくなり、結果としてレー
ザエネルギーが均一に吸収され均一な金属−半導
体合金層が形成される。そして、合金化されない
金属層を除去して後、熱処理して合金層を拡散源
として半導体基体に金属を拡散させることによ
り、常に一定量の金属が半導体基体に拡散される
ものである。 In the present invention, one main surface of a semiconductor substrate is irradiated with an ion beam to make the main surface amorphous, and then a metal layer is formed on the main surface of the substrate by vapor deposition or the like, and a laser beam is applied onto the metal layer. After irradiating light to form a metal-semiconductor alloy layer and selectively removing the unalloyed metal layer, heat treatment is performed to diffuse the metal into the semiconductor substrate using the alloy layer as a diffusion source. Eggplant. According to this method, the surface of the semiconductor substrate is made amorphous by irradiation with an ion beam, thereby forming a metal layer on the surface of the substrate, and when the metal layer is irradiated with laser light, heat absorption on the surface of the substrate occurs. Because of the good performance, even if there is a difference in laser intensity within the laser spot, the difference disappears due to heat conduction, and as a result, the laser energy is uniformly absorbed and a uniform metal-semiconductor alloy layer is formed. Then, after removing the unalloyed metal layer, heat treatment is performed to diffuse the metal into the semiconductor substrate using the alloy layer as a diffusion source, so that a certain amount of metal is always diffused into the semiconductor substrate.
因みに、最近レーザアニールによつて、合金層
を形成する方法が試みられており、レーザアニー
ル（パルスレーザの場合）を合金層形成に用いる
場合は、熱処理法に比べて熱平衡下の反応では生
じない合金層が得られたり、合金層の抵抗を減少
させたりする利点がある。しかし、半導体基体上
に金属層を蒸着してレーザパルスを照射すると、
レーザ光は金属層で吸収されるか、あるいは金属
層の面上で反射される。金属層で吸収されたレー
ザエネルギーは熱エネルギーに変換され、金属は
融解し半導体と合金を形成する。このとき融解し
た金属はレーザ光の吸収係数が大きくない半導体
と合金を作りながら、増々レーザ光を吸収し半導
体基体中に深く形成するという正の帰還作用がか
かる。従つて、レーザスポツトの中のレーザ強度
の差によつてスポツトの中でむらが生じ均一な合
金層を作るのが難しい。之に対して、本法ではイ
オンビーム照射で半導体基体表面を非晶質するこ
とにより、均一な金属−半導体合金層が得られ、
この合金層と相俟つて均一に且つ一定量の金属を
半導体基体に拡散させることができる。 Incidentally, a method of forming an alloy layer by laser annealing has recently been attempted, and when laser annealing (in the case of pulsed laser) is used to form an alloy layer, compared to heat treatment methods, the reaction under thermal equilibrium does not occur. There are advantages in that an alloy layer can be obtained and the resistance of the alloy layer can be reduced. However, when a metal layer is deposited on a semiconductor substrate and irradiated with laser pulses,
The laser light is either absorbed by the metal layer or reflected on the surface of the metal layer. The laser energy absorbed by the metal layer is converted into thermal energy, causing the metal to melt and form an alloy with the semiconductor. At this time, the molten metal creates an alloy with a semiconductor whose absorption coefficient for laser light is not large, and a positive feedback effect occurs in that the metal absorbs more and more laser light and is formed deep into the semiconductor substrate. Therefore, differences in laser intensity within the laser spot cause unevenness within the spot, making it difficult to form a uniform alloy layer. In contrast, in this method, a uniform metal-semiconductor alloy layer can be obtained by making the surface of the semiconductor substrate amorphous by ion beam irradiation.
Together with this alloy layer, it is possible to uniformly and uniformly diffuse a certain amount of metal into the semiconductor substrate.
次に、図面を参照して本発明の実施例について
述べる。本例は、ライフタイムキラーとして使わ
れるAu拡散に適用した場合である。 Next, embodiments of the present invention will be described with reference to the drawings. In this example, it is applied to Au diffusion, which is used as a lifetime killer.
先ず、第１図に示すようにPN接合を作り終つ
たシリコン半導体基板１の裏面１ａにイオン注入
法によつて例えばSi原子３をエネルギー250keV、
ドーズ量５×1015cm-2で打込む。このSiのイオン
注入により基体裏面には非晶質化層２が形成され
る。次に非晶質化された基体裏面１ａ上に蒸着に
よつてAu層４を被着形成して後、Au層４にレー
ザ光、例えばYAGレーザ光（イツトリウム・ア
ルミニウム・ガーネツト結晶による固体レーザか
らのレーザ光）５を照射して（第２図参照）、一
旦Si−Au合金層６を形成する（第３図参照）。こ
れにより、極めて均一性のよいSi−Au合金層６
が得られる。しかる後、Si−Au合金層６以外の
余分のAu層４を王水（硝酸と塩酸の混液）で除
去し（第４図参照）、その後、熱処理してSi−Au
合金層６を拡散源としてAuを基体１内に拡散す
る。かくすれば、常に一定のAu量が得られ、余
分なAuが素子内に拡散されることがなく信頼性
のよい素子が得られる。 First, as shown in FIG. 1, for example, Si atoms 3 are implanted into the back surface 1a of the silicon semiconductor substrate 1 with an energy of 250 keV by ion implantation onto the back surface 1a of the silicon semiconductor substrate 1 on which the PN junction has been formed.
Implant at a dose of 5×10 15 cm -2 . This Si ion implantation forms an amorphous layer 2 on the back surface of the substrate. Next, after forming an Au layer 4 by vapor deposition on the amorphous back surface 1a of the substrate, the Au layer 4 is coated with a laser beam, for example, a YAG laser beam (a solid-state laser using yttrium aluminum garnet crystal). (see FIG. 2) to once form a Si--Au alloy layer 6 (see FIG. 3). As a result, the Si-Au alloy layer 6 has extremely good uniformity.
is obtained. After that, the excess Au layer 4 other than the Si-Au alloy layer 6 is removed with aqua regia (a mixture of nitric acid and hydrochloric acid) (see Figure 4), and then heat-treated to form the Si-Au layer.
Au is diffused into the substrate 1 using the alloy layer 6 as a diffusion source. In this way, a constant amount of Au can always be obtained, excess Au will not be diffused into the device, and a highly reliable device can be obtained.
イオン注入原子としてはSi原子の他、半導体表
面を非晶質化させる原子であればよい。 In addition to Si atoms, the ion-implanted atoms may be atoms that cause the semiconductor surface to become amorphous.
尚、本発明は上例のSi基板へのAuの拡散に限
らず、半導体基体への金属拡散にも適用できるこ
とは勿論である。 It should be noted that the present invention is of course applicable not only to the diffusion of Au into the Si substrate described above, but also to the diffusion of metal into a semiconductor substrate.
上述せる本発明によれば、半導体基体に均一な
金属−半導体合金層を形成し、これを拡散源とし
て基体内に常に一定量の金属を拡散させることが
できる。従つて、例えば半導体素子へのライフタ
イムキラーとして使われる金属拡散等に適用して
好適ならしめるものである。 According to the present invention described above, a uniform metal-semiconductor alloy layer is formed on a semiconductor substrate, and a constant amount of metal can be constantly diffused into the substrate using this as a diffusion source. Therefore, it is suitable for application to, for example, metal diffusion used as a lifetime killer to semiconductor devices.
第１図乃至第４図は本発明の一実施例を示す工
程図である。
１はPN接合が形成された半導体基体、２は非
晶質化層、３はイオンビーム、４は金属層、５は
レーザビーム、６は金属−半導体合金層である。
1 to 4 are process diagrams showing one embodiment of the present invention. 1 is a semiconductor substrate in which a PN junction is formed, 2 is an amorphous layer, 3 is an ion beam, 4 is a metal layer, 5 is a laser beam, and 6 is a metal-semiconductor alloy layer.
Claims (1)
る工程、 上記主面上に金属層を形成する工程、 上記金属層上にレーザ光を照射して金属−半導
体の合金層を形成する工程、 合金化されずに残つた上記金属層を選択的に除
去する工程、 熱処理により上記合金層を拡散源にして上記半
導体基体に上記金属を拡散させる工程を有する金
属拡散方法。[Claims] 1. A step of irradiating one main surface of a semiconductor substrate with an ion beam, a step of forming a metal layer on the main surface, and a step of irradiating the metal layer with a laser beam to form a metal-semiconductor alloy layer. a step of selectively removing the remaining unalloyed metal layer; and a step of diffusing the metal into the semiconductor substrate by heat treatment using the alloy layer as a diffusion source.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16119779A JPS5683935A (en) | 1979-12-12 | 1979-12-12 | Formation of metal layer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16119779A JPS5683935A (en) | 1979-12-12 | 1979-12-12 | Formation of metal layer |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5683935A JPS5683935A (en) | 1981-07-08 |
| JPH0147004B2 true JPH0147004B2 (en) | 1989-10-12 |
Family
ID=15730424
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP16119779A Granted JPS5683935A (en) | 1979-12-12 | 1979-12-12 | Formation of metal layer |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5683935A (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| TW232751B (en) | 1992-10-09 | 1994-10-21 | Semiconductor Energy Res Co Ltd | Semiconductor device and method for forming the same |
| JP2746100B2 (en) * | 1994-02-08 | 1998-04-28 | 日本電気株式会社 | Method for manufacturing semiconductor device |
| JP7063242B2 (en) * | 2018-11-09 | 2022-05-09 | 株式会社デンソー | Manufacturing method of semiconductor device |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS55111128A (en) * | 1979-02-20 | 1980-08-27 | Nec Corp | Manufacturing method of semiconductor device |
-
1979
- 1979-12-12 JP JP16119779A patent/JPS5683935A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5683935A (en) | 1981-07-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4234356A (en) | Dual wavelength optical annealing of materials | |
| IE51992B1 (en) | Method for manufacturing a semiconductor device | |
| CN101878519A (en) | Method of forming back point contact structure of silicon solar cell | |
| US4659422A (en) | Process for producing monocrystalline layer on insulator | |
| US6232207B1 (en) | Doping process for producing homojunctions in semiconductor substrates | |
| JPH02152226A (en) | Manufacture of semiconductor device | |
| US4319119A (en) | Process for gettering semiconductor components and integrated semiconductor circuits | |
| JPH0147004B2 (en) | ||
| JPH0963974A (en) | Method of forming doping layer in semiconductor substrate | |
| CA1129969A (en) | Dual wavelength optical annealing of materials | |
| JP2002505520A (en) | Manufacturing method for microelectronic semiconductor structural members | |
| US7153760B2 (en) | Using acoustic energy including two lasers to activate implanted species | |
| JPS633447B2 (en) | ||
| JPS6250972B2 (en) | ||
| JPH0677155A (en) | Heat treatment method for semiconductor substrate | |
| US3469308A (en) | Fabrication of semiconductive devices | |
| JPS62271420A (en) | Treatment equipment for semiconductor substrate | |
| JPH07118444B2 (en) | Heat treatment method for semiconductor thin film | |
| JPS6119102B2 (en) | ||
| JPS59112617A (en) | Laser annealing method for semiconductor device | |
| Sapriel et al. | Raman vibrational studies of transient annealing of GaAs amorphous thin films | |
| JPS62274620A (en) | Annealing method for ion implanted layer | |
| JPS60154609A (en) | Manufacture of semiconductor device | |
| JPS5851509A (en) | Manufacture of semiconductor device | |
| JPS6175517A (en) | Compound semiconductor substrate annealing method |