JPS60236243A - Manufacture of semiconductor device - Google Patents

Manufacture of semiconductor device

Info

Publication number
JPS60236243A
JPS60236243A JP59092443A JP9244384A JPS60236243A JP S60236243 A JPS60236243 A JP S60236243A JP 59092443 A JP59092443 A JP 59092443A JP 9244384 A JP9244384 A JP 9244384A JP S60236243 A JPS60236243 A JP S60236243A
Authority
JP
Japan
Prior art keywords
layer
type
polished
mirror
substrate
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.)
Granted
Application number
JP59092443A
Other languages
Japanese (ja)
Other versions
JPH071791B2 (en
Inventor
Masaru Shinpo
新保 優
Kiyoshi Fukuda
潔 福田
Yoshiaki Owada
大和田 義明
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Toshiba Corp
Original Assignee
Toshiba Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Toshiba Corp filed Critical Toshiba Corp
Priority to JP59092443A priority Critical patent/JPH071791B2/en
Priority to DE8585300953T priority patent/DE3583183D1/en
Priority to EP85300953A priority patent/EP0161740B1/en
Priority to US06/701,516 priority patent/US4638552A/en
Publication of JPS60236243A publication Critical patent/JPS60236243A/en
Publication of JPH071791B2 publication Critical patent/JPH071791B2/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/04Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
    • H01L21/18Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table or AIIIBV compounds with or without impurities, e.g. doping materials
    • H01L21/30Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26
    • H01L21/302Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26 to change their surface-physical characteristics or shape, e.g. etching, polishing, cutting
    • H01L21/304Mechanical treatment, e.g. grinding, polishing, cutting
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/04Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
    • H01L21/18Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table or AIIIBV compounds with or without impurities, e.g. doping materials
    • H01L21/185Joining of semiconductor bodies for junction formation
    • H01L21/187Joining of semiconductor bodies for junction formation by direct bonding
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/04Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
    • H01L21/18Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table or AIIIBV compounds with or without impurities, e.g. doping materials
    • H01L21/20Deposition of semiconductor materials on a substrate, e.g. epitaxial growth solid phase epitaxy
    • H01L21/2003Deposition of semiconductor materials on a substrate, e.g. epitaxial growth solid phase epitaxy characterised by the substrate
    • H01L21/2007Bonding of semiconductor wafers to insulating substrates or to semiconducting substrates using an intermediate insulating layer
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/70Manufacture or treatment of devices consisting of a plurality of solid state components formed in or on a common substrate or of parts thereof; Manufacture of integrated circuit devices or of parts thereof
    • H01L21/71Manufacture of specific parts of devices defined in group H01L21/70
    • H01L21/74Making of localized buried regions, e.g. buried collector layers, internal connections substrate contacts
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/70Manufacture or treatment of devices consisting of a plurality of solid state components formed in or on a common substrate or of parts thereof; Manufacture of integrated circuit devices or of parts thereof
    • H01L21/71Manufacture of specific parts of devices defined in group H01L21/70
    • H01L21/76Making of isolation regions between components
    • H01L21/762Dielectric regions, e.g. EPIC dielectric isolation, LOCOS; Trench refilling techniques, SOI technology, use of channel stoppers
    • H01L21/7624Dielectric regions, e.g. EPIC dielectric isolation, LOCOS; Trench refilling techniques, SOI technology, use of channel stoppers using semiconductor on insulator [SOI] technology
    • H01L21/76251Dielectric regions, e.g. EPIC dielectric isolation, LOCOS; Trench refilling techniques, SOI technology, use of channel stoppers using semiconductor on insulator [SOI] technology using bonding techniques

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Manufacturing & Machinery (AREA)
  • Computer Hardware Design (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Power Engineering (AREA)
  • Bipolar Transistors (AREA)
  • Element Separation (AREA)
  • Metal-Oxide And Bipolar Metal-Oxide Semiconductor Integrated Circuits (AREA)
  • Recrystallisation Techniques (AREA)

Abstract

PURPOSE:To form a buried layer with good controllability in simple steps by selectively forming a diffused layer on the surface of the mirror-polished first semiconductor substrate, and bonding to the mirror-polished second semiconductor under clean atmosphere. CONSTITUTION:A n<+> type layer 22 is selectively diffused on the surface of a mirror-polished p type Si substrate 21. The layer 22 becomes a collector buried layer. An n<+> type layer 24 to become a collector leading layer and a p<+> type layer 25 to become an element separating layer are diffused and formed on the surface of a mirror-polished n<-> type Si substrate 23. The surface roughness of the mirror-polished surface is preferably 100Angstrom or less. After the substrates 21, 23 are sufficiently cleaned and dried, the polished surfaces are contacted and bonded in clean atmosphere. A heat treatment is executed at 200 deg.C or higher or preferably approx. 1,000 deg.C to sufficiently increase the bonding strength. The thickness is regulated by polishing and etching to form a p type base layer 26 and an n<+> type emitter layer 27.

Description

【発明の詳細な説明】 (発明の技術分野〕 本発明は、内部に埋込み層を有する半導体基板の製造方
法に関する。
DETAILED DESCRIPTION OF THE INVENTION (Technical Field of the Invention) The present invention relates to a method for manufacturing a semiconductor substrate having a buried layer therein.

(発明の技術的背景とその問題点) バイポーラICのように、素子基板の内部に不純物や濃
度の異なる埋込み層を必要とするものは多い。第1図は
その様な一例として、一般的なバイポーラICを示して
いる。この製造工程は次の通りである。先ず、p形Si
基板11に選択拡散によりコレクタ埋込み層となるn“
層12を形成する。次いてこの基板上にエピタキシャル
成長法によってn一層13を形成する。こうして(qら
れたエピタキシャル基板にpベース層14.n+ソース
層15を順次拡散形成してトランジスタを得る。16は
素子分離用のp+拡散層であり、17はコレクタ電極取
出しのためのn+拡散層である。
(Technical Background of the Invention and Problems thereof) Many ICs, such as bipolar ICs, require buried layers with different impurities or concentrations inside the element substrate. FIG. 1 shows a typical bipolar IC as one such example. This manufacturing process is as follows. First, p-type Si
n" which becomes a collector buried layer by selective diffusion on the substrate 11
Form layer 12. Next, an n-layer 13 is formed on this substrate by epitaxial growth. In this way, a p base layer 14 and an n+ source layer 15 are successively diffused into the (q) epitaxial substrate to obtain a transistor. 16 is a p+ diffusion layer for element isolation, and 17 is an n+ diffusion layer for taking out the collector electrode. It is.

従来のこの様な方法では、埋込み層の深さはエピタキシ
ャル成長層の厚みで決まる。しかしながら、エピタキシ
ャル法では成長速度に限界があるため、厚い層を得るた
めには極めて長時間を要(る。しかも高度の技術を必要
とし、制御が難しいために欠陥等を生じ易い。また長時
間の1ビタキシヤル成長工程で埋込み層の不純物が再拡
散するため、埋込み層上のエピタキシャル層の厚み制御
も難しい。
In such conventional methods, the depth of the buried layer is determined by the thickness of the epitaxially grown layer. However, the epitaxial method has a limited growth rate, so it takes an extremely long time to obtain a thick layer.Moreover, it requires advanced technology and is difficult to control, which tends to cause defects. Since impurities in the buried layer are re-diffused during the first bitaxial growth step, it is also difficult to control the thickness of the epitaxial layer on the buried layer.

〔発明の目的〕[Purpose of the invention]

本発明は上記の点に鑑みてなされたもので、簡単な工程
で制御性よく埋込み層を形成するように(、た+−導体
塁恢の製造方法を提供することを目的とりる。
The present invention has been made in view of the above points, and it is an object of the present invention to provide a method for manufacturing a conductor base so as to form a buried layer with good controllability in a simple process.

〔光用の概要〕[Outline for optical use]

本発明は、2枚の半導体基板を直接接合させて一枚の半
導体基板を得るという方法を利用する。
The present invention utilizes a method of directly bonding two semiconductor substrates to obtain one semiconductor substrate.

このような半導体同士の接合によって不純物濃度の異な
る層を内部に形成する方法自体は、合金形半導体接合法
として古くから知られた技術である。
The method of forming internal layers with different impurity concentrations by bonding semiconductors together is a technique that has been known for a long time as an alloy semiconductor bonding method.

しかしこの方法は坦在一般に利用されていない。However, this method is not generally used.

その理由は、この方法では、1300℃という、半導体
の融点に近い^瀧まで加熱し加圧する必要があり、その
結果、半導体結晶に多くの欠陥や変成層が形成されるた
めである。
The reason is that this method requires heating and pressurizing to 1300° C., which is close to the melting point of the semiconductor, and as a result, many defects and metamorphosed layers are formed in the semiconductor crystal.

これに対し、本発明者らは、半導体基板の表面を充分に
鏡面研磨して、その研磨面どうしを充分i′lIi浄な
雰囲気下で密着させることにより、強固な接合体が得ら
れることを見出した。この接合体は200’C以上の温
度で熱処理すれば、接合がより強固なものとなる。この
接合のメカニズムは未だ不明な点が多いが、鏡面研磨面
に形成される自然酸化膜が重要な役割を果たしているら
しいことが推測される。
In contrast, the present inventors have discovered that a strong bonded body can be obtained by sufficiently mirror-polishing the surface of a semiconductor substrate and bringing the polished surfaces into close contact with each other in a sufficiently clean atmosphere. I found it. If this bonded body is heat treated at a temperature of 200'C or higher, the bond will become stronger. Although many aspects of this bonding mechanism are still unclear, it is speculated that the natural oxide film formed on the mirror-polished surface seems to play an important role.

本発明は、この新しい技術を利用して、先ず鏡面研磨さ
れた第1の半導体基板の表面に選択的に拡散層を形成し
、これを鏡面研磨された第2の半導体基板と研磨面同士
を対向させてm浄な雰囲気下で接合させ、1300℃を
超えない範囲で熱処理することにより、埋込み層を有す
る半導体基板を得る。鏡面研磨面の表面粗さは1100
A、下であることが望ましい。熱処理温度は200℃程
度以上であればよく、望ましくは1000℃程度である
が、1300″C程度まで高くすると結晶欠陥などの発
生があるため、ここまで高くすることは出来ない。
The present invention utilizes this new technology to first selectively form a diffusion layer on the surface of a mirror-polished first semiconductor substrate, and then to connect the polished surfaces to a mirror-polished second semiconductor substrate. A semiconductor substrate having a buried layer is obtained by facing each other and bonding in a clean atmosphere, and heat-treating at a temperature not exceeding 1300°C. Surface roughness of mirror polished surface is 1100
A: It is desirable that it be lower. The heat treatment temperature may be about 200° C. or higher, preferably about 1000° C., but if it is raised to about 1300″C, crystal defects will occur, so it cannot be made this high.

〔発明の効果〕〔Effect of the invention〕

本発明によれば、長時間のエピタキシトル成長等を要せ
ず、簡単に埋込み層を持つ半導体基板を得ることができ
る。しかも熱処理は高温を要しないから、埋込み層が高
不純物濃度層である場合にも不純物の再拡散は最少限に
押えられ、埋込み層の深さや濃度を制御性よく設定する
ことができる。
According to the present invention, a semiconductor substrate having a buried layer can be easily obtained without requiring long-term epitaxial growth. Furthermore, since the heat treatment does not require high temperatures, re-diffusion of impurities can be suppressed to a minimum even when the buried layer is a layer with high impurity concentration, and the depth and concentration of the buried layer can be set with good controllability.

従ってICその他の素子製造の工程短縮化や素子性能p
向上を図ることができる。
Therefore, it is possible to shorten the process of manufacturing ICs and other elements, and increase the performance of the elements.
You can improve your performance.

〔発明の実施例〕[Embodiments of the invention]

以下本発明をバイポーラI C’に適用した実施例につ
いて第2図(a)〜′(e)を用いて説明する。
An embodiment in which the present invention is applied to a bipolar IC' will be described below with reference to FIGS. 2(a) to 2'(e).

第2図(a)は、表面粗さ500Å以下に充分平滑に鏡
面研磨されたp型3i基板(第1の半導体基板)21の
表面にn+型層22を選択的に拡散形成した状態を示し
ている。n+型層22はコレクタ埋込み層どなるもので
ある。第2図(b)は同様に鏡面研磨されたn−型Si
l板(第2の半導体基板)23であり、その表面にコレ
クタ取出し層となるn+型層24及び素子分離層となる
p′″型層25が拡散形成された状態を示している。
FIG. 2(a) shows a state in which an n+ type layer 22 is selectively diffused and formed on the surface of a p-type 3i substrate (first semiconductor substrate) 21 which has been mirror-polished to a sufficiently smooth surface with a surface roughness of 500 Å or less. ing. The n+ type layer 22 is a collector buried layer. Figure 2(b) shows n-type Si that has been mirror-polished in the same way.
The figure shows a state in which an n+ type layer 24 serving as a collector extraction layer and a p'' type layer 25 serving as an element isolation layer are diffused and formed on the surface of an L plate (second semiconductor substrate) 23.

これらの基板を充分に洗浄し、乾燥させた後、ゴミなど
の異物が介在しない清浄な雰囲気中で第2図(C)に示
すように研磨面どうしを密着させて接合する。この接合
体は熱処理をしなくてもかなりの接合強度が得られるが
、200℃以上、好ましくは1000℃程度で熱処理し
て接合強度を充分強固なものとする。こうしてn1型1
122が埋め込まれ、素子分離層とコレクタ取出し層が
形成されただIC基板が1りられる。この基板はそのま
ま用いてもよいが、必要に応じて第2図(d)に示すよ
うに、研磨やエツチングにより厚みを調整し、その後第
2図(e)に示すようにp型ベース@26.n+型エミ
ッタ層27を形成する。
After thoroughly cleaning and drying these substrates, the polished surfaces are brought into close contact with each other and bonded in a clean atmosphere free from foreign matter such as dust, as shown in FIG. 2(C). Although this bonded body can have a considerable bonding strength without being heat-treated, it is heat-treated at 200° C. or higher, preferably about 1000° C., to make the bonding strength sufficiently strong. Thus n1 type 1
122 is buried, an element isolation layer and a collector extraction layer are formed, and an IC substrate is removed. This substrate may be used as it is, but if necessary, the thickness may be adjusted by polishing or etching as shown in FIG. 2(d), and then the p-type base@26 .. An n+ type emitter layer 27 is formed.

こtして本実施例によれば、エピタキシャル基板を用い
ることなく、極めて簡単な工程で浸れた素子特性を示す
バイポーラICが得られる。
According to this embodiment, a bipolar IC exhibiting excellent device characteristics can be obtained through an extremely simple process without using an epitaxial substrate.

上記実施例では、埋込み層が高濃度不純物層の場合を説
明したが、本発明はこれに限られるものではなく、導電
型や導電度が上記実施例とは異なる神々の埋込み層を必
要とする基板に適用して同様の効果が得られる。
In the above embodiment, the case where the buried layer is a high concentration impurity layer has been explained, but the present invention is not limited to this, and requires a buried layer with a different conductivity type and degree from those in the above embodiment. A similar effect can be obtained by applying it to a substrate.

【図面の簡単な説明】[Brief explanation of the drawing]

第1図はバイポーラICの一般的な構造を示す図、第2
図(a)〜(e)は本発明の一実施例によるバイポーラ
ICの製造1碇を示す図である。 21・・・p++S1基板(第1の半導体基板)、22
・・・n+型型数散層埋込み層)、23・・・n−型3
i基板(第2の半導体基板)、24・・・n+型拡敞層
、25・・・p+型型数散層26・・・p型ヘース層2
7・・・n++エミッタ層。 (a) (b) 第1は 第20 2
Figure 1 shows the general structure of a bipolar IC, Figure 2 shows the general structure of a bipolar IC.
Figures (a) to (e) are diagrams showing one anchor for manufacturing a bipolar IC according to an embodiment of the present invention. 21...p++S1 substrate (first semiconductor substrate), 22
...n+ type scattered buried layer), 23...n- type 3
i substrate (second semiconductor substrate), 24...n+ type diffusion layer, 25...p+ type scattering layer 26...p type Hess layer 2
7...n++ emitter layer. (a) (b) 1st is 20th 2nd

Claims (1)

【特許請求の範囲】[Claims] 内部に埋込み層を有する半導体基板を製造する方法であ
って、鏡面研磨された第1の半導体基板の表面に選択的
に拡散層を形成する工程と、鏡面F+IIIIされた第
2の半導体基板を前記第1の半導体基板と研磨面どうし
を対向させて清浄な雰囲気下で接合させる工程とを備え
たことを特徴とづ−る半導体基板の製造方法。
A method for manufacturing a semiconductor substrate having a buried layer therein, comprising the steps of selectively forming a diffusion layer on the surface of a mirror-polished first semiconductor substrate; A method for manufacturing a semiconductor substrate, comprising the step of bonding a first semiconductor substrate and polished surfaces facing each other in a clean atmosphere.
JP59092443A 1984-05-09 1984-05-09 Method for manufacturing semiconductor substrate Expired - Lifetime JPH071791B2 (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
JP59092443A JPH071791B2 (en) 1984-05-09 1984-05-09 Method for manufacturing semiconductor substrate
DE8585300953T DE3583183D1 (en) 1984-05-09 1985-02-13 METHOD FOR PRODUCING A SEMICONDUCTOR SUBSTRATE.
EP85300953A EP0161740B1 (en) 1984-05-09 1985-02-13 Method of manufacturing semiconductor substrate
US06/701,516 US4638552A (en) 1984-05-09 1985-02-14 Method of manufacturing semiconductor substrate

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP59092443A JPH071791B2 (en) 1984-05-09 1984-05-09 Method for manufacturing semiconductor substrate

Publications (2)

Publication Number Publication Date
JPS60236243A true JPS60236243A (en) 1985-11-25
JPH071791B2 JPH071791B2 (en) 1995-01-11

Family

ID=14054550

Family Applications (1)

Application Number Title Priority Date Filing Date
JP59092443A Expired - Lifetime JPH071791B2 (en) 1984-05-09 1984-05-09 Method for manufacturing semiconductor substrate

Country Status (1)

Country Link
JP (1) JPH071791B2 (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS62128532A (en) * 1985-11-30 1987-06-10 Toshiba Corp Semiconductor device and manufacture thereof
JPS62229820A (en) * 1986-03-31 1987-10-08 Toshiba Corp Manufacture of semiconductor device
JPS6376485A (en) * 1986-09-19 1988-04-06 Komatsu Ltd Manufacture of semiconductor device
WO2020084782A1 (en) * 2018-10-26 2020-04-30 ウルトラメモリ株式会社 Semiconductor device and method of manufacturing same

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS62128532A (en) * 1985-11-30 1987-06-10 Toshiba Corp Semiconductor device and manufacture thereof
JPH0473615B2 (en) * 1985-11-30 1992-11-24
JPS62229820A (en) * 1986-03-31 1987-10-08 Toshiba Corp Manufacture of semiconductor device
JPS6376485A (en) * 1986-09-19 1988-04-06 Komatsu Ltd Manufacture of semiconductor device
WO2020084782A1 (en) * 2018-10-26 2020-04-30 ウルトラメモリ株式会社 Semiconductor device and method of manufacturing same

Also Published As

Publication number Publication date
JPH071791B2 (en) 1995-01-11

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