JPS6372158A - Manufacture of high-speed semiconductor device - Google Patents
Manufacture of high-speed semiconductor deviceInfo
- Publication number
- JPS6372158A JPS6372158A JP21505586A JP21505586A JPS6372158A JP S6372158 A JPS6372158 A JP S6372158A JP 21505586 A JP21505586 A JP 21505586A JP 21505586 A JP21505586 A JP 21505586A JP S6372158 A JPS6372158 A JP S6372158A
- Authority
- JP
- Japan
- Prior art keywords
- layer
- etching
- ingaas
- emitter
- barrier layer
- 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
Links
- 239000004065 semiconductor Substances 0.000 title claims description 15
- 238000004519 manufacturing process Methods 0.000 title claims description 7
- 238000000034 method Methods 0.000 claims abstract description 30
- 238000005530 etching Methods 0.000 claims abstract description 29
- 229910000530 Gallium indium arsenide Inorganic materials 0.000 claims abstract description 15
- 238000001312 dry etching Methods 0.000 claims abstract description 6
- 240000002329 Inga feuillei Species 0.000 claims description 2
- 230000004888 barrier function Effects 0.000 abstract description 23
- 238000001039 wet etching Methods 0.000 abstract description 6
- 238000001020 plasma etching Methods 0.000 abstract description 4
- 239000000758 substrate Substances 0.000 abstract description 3
- PXBRQCKWGAHEHS-UHFFFAOYSA-N dichlorodifluoromethane Chemical compound FC(F)(Cl)Cl PXBRQCKWGAHEHS-UHFFFAOYSA-N 0.000 abstract description 2
- 235000019404 dichlorodifluoromethane Nutrition 0.000 abstract description 2
- 229910000980 Aluminium gallium arsenide Inorganic materials 0.000 abstract 1
- 229910001218 Gallium arsenide Inorganic materials 0.000 description 12
- KRHYYFGTRYWZRS-UHFFFAOYSA-N Fluorane Chemical compound F KRHYYFGTRYWZRS-UHFFFAOYSA-N 0.000 description 3
- 150000001875 compounds Chemical class 0.000 description 3
- 239000012535 impurity Substances 0.000 description 3
- 229920002120 photoresistant polymer Polymers 0.000 description 3
- 230000000694 effects Effects 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 229960002050 hydrofluoric acid Drugs 0.000 description 2
- 238000002347 injection Methods 0.000 description 2
- 239000007924 injection Substances 0.000 description 2
- 238000000926 separation method Methods 0.000 description 2
- 230000003321 amplification Effects 0.000 description 1
- 238000000407 epitaxy Methods 0.000 description 1
- 239000002784 hot electron Substances 0.000 description 1
- 238000003199 nucleic acid amplification method Methods 0.000 description 1
- 238000000206 photolithography Methods 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 238000007738 vacuum evaporation Methods 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L29/00—Semiconductor devices adapted for rectifying, amplifying, oscillating or switching, or capacitors or resistors with at least one potential-jump barrier or surface barrier, e.g. PN junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
- H01L29/66—Types of semiconductor device ; Multistep manufacturing processes therefor
- H01L29/68—Types of semiconductor device ; Multistep manufacturing processes therefor controllable by only the electric current supplied, or only the electric potential applied, to an electrode which does not carry the current to be rectified, amplified or switched
- H01L29/76—Unipolar devices, e.g. field effect transistors
- H01L29/7606—Transistor-like structures, e.g. hot electron transistor [HET]; metal base transistor [MBT]
Abstract
Description
【発明の詳細な説明】
〔概要〕
本発明は、高速半導体装置の製造方法に於いて、I n
G a A、s層の選択的エツチングを行うに際して
ドライ・エッチング法を適用し、その下地であり且つヘ
テロ接合を生成させる為のIn(Aβ8Ga、−X)A
s (0<x≦1)からなるバリヤ層をエツチング・
ストッパとして利用することを可能にして、その結果、
前記I n (A I XG a I−X )As
(0<X≦1)バリヤ層の下地になっている薄いInG
aAsベース層が損傷されるのを防止できるようにした
。[Detailed Description of the Invention] [Summary] The present invention provides a method for manufacturing a high-speed semiconductor device.
When performing selective etching of the G a A, s layer, a dry etching method is applied, and In(Aβ8Ga, -X)A, which is the underlying layer and is used to generate a heterojunction, is applied.
Etching the barrier layer consisting of s (0<x≦1)
It makes it possible to use it as a stopper, and as a result,
Said I n (A I XG a I-X ) As
(0<X≦1) Thin InG underlying the barrier layer
This makes it possible to prevent the aAs base layer from being damaged.
本発明は、化合物半導体としてInGaAs/InA#
GaAs系を用いたホット・エレクトロン・トランジス
タ(hot electrontrans is t
or :HET)と呼ばれる高速半導体装置を製造する
方法の改良に関する。The present invention uses InGaAs/InA# as a compound semiconductor.
Hot electron transistor using GaAs
The present invention relates to an improvement in a method for manufacturing a high-speed semiconductor device called a high-speed semiconductor device (HET).
従来、化合物半導体としてG a A s / A I
G aAs系を用い、Aj2GaAsをエミッタ側バ
リヤ層及びコレクタ側バリヤとしたHETが知られてい
る。Conventionally, GaAs/AI as a compound semiconductor
A HET using a GaAs system and having Aj2GaAs as an emitter-side barrier layer and a collector-side barrier layer is known.
このHETでは、r谷−L谷間の分離エネルギが小さい
為、電子の注入エネルギを大きくした場合、電子がr谷
からし谷に移行し易い旨の欠点がある。In this HET, since the separation energy between the r valley and the L valley is small, there is a drawback that when the electron injection energy is increased, the electrons tend to migrate from the r valley to the negative valley.
若し、電子がL谷に移行すれば、その実効質量が増加し
、従って、インター・バレー(inter valle
y)散乱を受は易(なり、その結果、走行速度が低下し
、また、ベース中で消滅する率が高くなるから、スイッ
チング・スピードの低下や電流利得hFtの低下を招来
する。If an electron moves to the L valley, its effective mass increases and therefore becomes inter valley.
y) It is easily subject to scattering, resulting in a decrease in running speed and a high rate of annihilation in the base, resulting in a decrease in switching speed and a decrease in current gain hFt.
そこで、このような欠点を回避する為、化合物半導体と
してI n G a A S / I n A I G
a A S系を用い、InAj!GaAsをエミッタ
側バリヤ層及びコレクタ側バリヤ層としたHETが開発
された。Therefore, in order to avoid such drawbacks, InGaAs/InnAIG is used as a compound semiconductor.
Using the a A S system, InAj! A HET using GaAs as an emitter-side barrier layer and a collector-side barrier layer has been developed.
このHETでは、GaAs/Aj!GaAs系を用いた
HETの場合、と全く逆のことが言える。即ち、r谷−
L谷間の分離エネルギは大である為、電子の注入エネル
ギを大きくすることができ、従って、電流増幅率hrE
を向上することができるものである。In this HET, GaAs/Aj! The exact opposite is true for HETs using GaAs. That is, r valley-
Since the separation energy of the L valley is large, the electron injection energy can be increased, and therefore the current amplification factor hrE
This is something that can be improved.
前記したI nGaAs/I nAlGaAs系のHE
Tに於いては、n型1 nGaA3エミツタ層の下にi
型1nAJGaAsエミッタ側バリヤ層が、また、その
更に下にn型I nGaAsベース層が存在し、そのベ
ース層からベース電極を取り出すには、エミツタ層及び
エミッタ側バリヤ層をメサ・エツチングしてベース層を
表出しなければならない。The aforementioned I nGaAs/I nAlGaAs-based HE
In T, there is i under the n-type 1 nGaA3 emitter layer.
There is a type 1nA JGaAs emitter-side barrier layer and an n-type InGaAs base layer below it.To take out the base electrode from the base layer, the emitter layer and emitter-side barrier layer are mesa-etched to remove the base layer. must be expressed.
従来、そのようなメサ・エツチングを行うには、エッチ
ャントをフッ酸系エツチング液とするウェット・エッチ
ング法を適用しているが、InGaAsのエツチング・
レートと7 nAlGaAsのそれとは大差なく、しか
も、エツチングすべきエミツタ層及びエミッタ側バリヤ
層の厚さは、その両方で2250 C人〕以上にもなり
、それに対して、ベース層は200〔人〕〜1000
(人〕の厚さである為、制御性良く前記メサ・エツチン
グを行うことは甚だ困難であり、ベース層が損傷された
り、また、特に薄いベース層の場合には、突き抜けを生
じたりする。Conventionally, such mesa etching has been performed using a wet etching method using a hydrofluoric acid-based etchant as the etchant.
The etching rate is not much different from that of 7nAlGaAs, and the thickness of the emitter layer and emitter-side barrier layer to be etched is more than 2250 C for both, whereas the base layer is 200 C. ~1000
Because of the thickness of the base layer, it is extremely difficult to perform the mesa etching with good control, and the base layer may be damaged or, especially in the case of a thin base layer, break-through may occur.
本発明は、前記のようなメサ・エツチングを行う場合、
所要半導体層の表面が損傷されることなく確実に露出す
ることが可能な高速半導体装置の製造方法を提供する。In the present invention, when performing mesa etching as described above,
Provided is a method for manufacturing a high-speed semiconductor device that can reliably expose the surface of a required semiconductor layer without damaging it.
本発明に依る高速半導体装置の製造方法に於いては、ヘ
テロ接合を生成するべく順に積層されているI n (
AN、Gat−x )As (0<x≦1)層(例えば
I nAfGaAsエミッタ側バリヤ層5)とInGa
AsJi!(例えばn+梨型1nGaAエミッタ層6)
とを選択的にエツチングするに際し、先ず、ドライ・エ
ッチング法(例えばCCβ2F2をエツチング・ガスと
する反応性イオン・エツチング法)にてInGaAs層
のエツチングを行ってIn <Alx Ga1−x )
As (0<x≦1)層に達した際に停止さす、次い
で、ウェット・エッチング法でI n (A lx G
a l−X ) A s(0〈x≦1)層をエツチン
グする工程が含まれてなる構成になっている。In the method for manufacturing a high-speed semiconductor device according to the present invention, I n (
AN, Gat-x) As (0<x≦1) layer (e.g. InAfGaAs emitter side barrier layer 5) and InGa
As Ji! (For example, n+ pear-shaped 1nGaA emitter layer 6)
When selectively etching the InGaAs layer, first, the InGaAs layer is etched by a dry etching method (e.g., a reactive ion etching method using CCβ2F2 as an etching gas).
The process is stopped when the As (0<x≦1) layer is reached, and then wet etching is performed to remove I n (A lx G
The structure includes a step of etching the a l-X ) A s (0<x≦1) layer.
前記手段を採ることに依り、前記In(A/XCFal
−X )As (0<X≦1)層の下地になっている
InGaAs層に損傷を与えずに高精度で表面を選択的
に露出させることが可能となり、従って、そこから容易
且つ確実に電極を取り出すことができるから、HETの
ような高速半導体装置のベース電極を形成する技術とし
て好適である。By taking the above means, the In(A/XCFal
-X) As It is possible to selectively expose the surface with high precision without damaging the underlying InGaAs layer (0<X≦1) layer, and therefore it is possible to easily and reliably expose the electrode from there. Since it is possible to take out the following, it is suitable as a technique for forming base electrodes of high-speed semiconductor devices such as HETs.
第1図乃至第4図は本発明一実施例を解説する為の工程
要所に於けるHETの要部切断側面図を表し、以下、こ
れ等の図を参照しつつ説明する。1 to 4 are cut-away side views of essential parts of the HET at key points in the process for explaining one embodiment of the present invention, and the following description will be made with reference to these figures.
第1図参照
(1) 分子線エピタキシャル成長(molecul
ar beam epitaxy:MBE)を適用
することに依り、InP基板1上にn+型InGaAs
コレクタ層2、i型InAl!GaAsコレクタ側バリ
ヤ層3、n型1nGaAsベ一ス層4、i型1 n A
j! G a A sエミッタ側バリヤ層5、n+型
InCraAsエミフタ層6を成長させる。See Figure 1 (1) Molecular beam epitaxial growth
By applying ar beam epitaxy (MBE), n+ type InGaAs is deposited on the InP substrate 1.
Collector layer 2, i-type InAl! GaAs collector side barrier layer 3, n-type 1nGaAs base layer 4, i-type 1nA
j! A GaAs emitter side barrier layer 5 and an n+ type InCraAs emitter layer 6 are grown.
この場合の各半導体層に関する主要データを例示すると
次の通りである。Examples of main data regarding each semiconductor layer in this case are as follows.
■ コレクタ層2について
厚さ:3000 (人〕
不純物濃度: 5 X 10I8(cIn−”)■ コ
レクタ側バリヤ層3について
厚さ:1000(人〕〜3000 (人〕■ ベース
層4について
厚さ:200 C人〕〜1000 (人〕不純物濃
度: l X I Q10(cm−’)(4)エミッタ
側バリヤ層5について
厚さ:250(人〕
(5)エミツタ層6について
厚さ:2000 (人〕
不純物濃度: 5 X I Q10(am−”)第2図
参照
(2)通常のフォト・リソグラフィ技術に於けるレジス
ト・プロセスを適用することに依り、エツチング・マス
クとなるフォト・レジスト膜10を形成する。■ Thickness of collector layer 2: 3000 (people) Impurity concentration: 5 x 10I8 (cIn-'') ■ Thickness of collector side barrier layer 3: 1000 (people) to 3000 (people) ■ Thickness of base layer 4: 200 C people] to 1000 (people) Impurity concentration: l ] Impurity concentration: 5 X I Q10 (am-'') See Figure 2. (2) By applying a resist process in normal photolithography technology, a photoresist film 10 that will serve as an etching mask is formed. Form.
(3) CC12F 2をエツチング・ガスとする反
応性イオン・エツチング(reactive ion
etching:RIE)法を適用することに依り
、フォト・レジスト膜10をマスクとしてn+型InG
aASエミッタIW6をメサ状にエツチングする。(3) Reactive ion etching using CC12F2 as the etching gas
By applying the etching (RIE) method, n+ type InG is formed using the photoresist film 10 as a mask.
The aAS emitter IW6 is etched into a mesa shape.
エツチング・ガスとしてCCl2F2を用いた場合、l
nQaAs : I nAj!GaAsのエツチング
選択比を約5:1とすることができ、エツチングをIn
AfGaAsエミッタ側バリヤ層5の表面で停止させる
ことは容易である。When CCl2F2 is used as the etching gas, l
nQaAs: I nAj! The etching selection ratio of GaAs can be set to about 5:1, and the etching is
It is easy to stop at the surface of the AfGaAs emitter side barrier layer 5.
この場合のエツチング条件を例示すると次の通りである
。Examples of etching conditions in this case are as follows.
高周波型カニ200(W)
ガス圧:3(Pa)
CC7!2F2流量: 40 (SCCM)(stan
dard cub
ic centimete
r per m1nute
:SCCM)
第3図参照
(4)エッチャントをフン酸系(HF+H2O2十H2
0)エツチング液とするウェット・エッチング法を適用
することに依り、エミッタ側バリヤ層5のエツチングを
行う。High frequency type crab 200 (W) Gas pressure: 3 (Pa) CC7!2F2 flow rate: 40 (SCCM) (stan
(dard cubic centimeter per m1nute: SCCM) Refer to Figure 3. (4) Use a fluoric acid-based etchant (HF +
0) Etching the emitter side barrier layer 5 by applying a wet etching method using an etching solution.
°エミッタ側バリヤ層5の厚さは250 〔人〕である
から、通常のウェット・エッチング法を用いても、かな
り高精度でエツチングすることができる。Since the thickness of the emitter-side barrier layer 5 is 250 .mu.m, it can be etched with fairly high precision even if a normal wet etching method is used.
第4図参照
(5) コレクタ電極を取り出す為のコレクタ層9を
表出するメサ・エツチング、素子間分離を行う為のメサ
・エツチングなどを行ってから、通常の技法、例えば真
空蒸着法及びリフト・オフ法等を適用してエミッタ電極
7、ベース電極8、コレクタ電極9を形成する。尚、ベ
ース層4、コレクタ側バリヤN3をメサ・エツチングし
てコレクタ層9の一部を表出させる際、通常のウェット
・エッチング法を適用しても、コレクタN2は充分に厚
いので問題はない。See Figure 4 (5) After performing mesa etching to expose the collector layer 9 to take out the collector electrode and mesa etching to isolate between elements, use the usual techniques such as vacuum evaporation and lift. - Form the emitter electrode 7, base electrode 8, and collector electrode 9 by applying an off method or the like. Note that when mesa-etching the base layer 4 and the collector side barrier N3 to expose a part of the collector layer 9, there is no problem even if a normal wet etching method is applied because the collector N2 is sufficiently thick. .
本発明に依る高速半導体装置の製造方法に於いては、I
nGaAs層の選択的エツチングを行うに際してドライ
・エッチング法を適用することに依って、その下地であ
り且つペテロ接合を生成させる為のI n (AA’X
Gap−x ) As (0< x≦1)からなるバ
リヤ層をエツチング・ストッパとして利用できる構成に
なっている。In the method for manufacturing a high-speed semiconductor device according to the present invention, I
By applying a dry etching method when performing selective etching of the nGaAs layer, I n (AA'X
Gap-x ) As (0<x≦1), the barrier layer can be used as an etching stopper.
前記構成を採ることに依り、前記In(A1えGap−
、)As (0<x≦1)層の下地になッテいるIn
GaAs層に損傷を与えずに高精度で表面を選択的に露
出させることが可能となり、従って、そこから容易且つ
確実に電極を取り出すことができるから、HETのよう
な高速半導体装置のベース電極を形成する技術として好
適である。By adopting the above configuration, the In(A1 and Gap-
, ) As (0<x≦1)
It is possible to selectively expose the surface of the GaAs layer with high precision without damaging it, and therefore the electrode can be taken out easily and reliably from there, making it suitable for use as base electrodes in high-speed semiconductor devices such as HETs. This is suitable as a forming technique.
第1図乃至第4図は本発明一実施例を説明する為の工程
要所に於けるHETの要部切断側面図を表している。
図に於いて、1はInP基板、2はn+型InGaAs
コレクタ層、3はi型! n A A G a A s
コレクタ側バリヤ層、4はn型1nGaAsベ一ス層、
5はi型InAj!GaAsエミッタ側バリヤ層、6は
n+型1 nGaAs!GaAsコレクタ層ッタ電極、
8はベース電極、9はコレクタ電極、10はフォト・レ
ジスト膜をそれぞれ示している。FIGS. 1 to 4 are cross-sectional side views of essential parts of the HET at key points in the process for explaining one embodiment of the present invention. In the figure, 1 is an InP substrate, 2 is an n+ type InGaAs
Collector layer, 3 is type I! n A A G a A s
Collector side barrier layer, 4 is n-type 1nGaAs base layer,
5 is type i InAj! GaAs emitter side barrier layer, 6 is n+ type 1 nGaAs! GaAs collector layer electrode,
Reference numeral 8 indicates a base electrode, 9 a collector electrode, and 10 a photoresist film.
Claims (1)
xGa_1_−_x)As(0<x≦1)層とInGa
As層とを選択的にエッチングするに際し、先ず、ドラ
イ・エッチング法にてInGaAs層のエッチングを行
ってIn(Al_xGa_1_−_x)As(0<x≦
1)層に達した際に停止させ、次に、ウェット・エッチ
ング法にてIn(Al_xGa_1_−_x)As(0
<x≦1)層をエッチングする工程 が含まれてなることを特徴とする高速半導体装置の製造
方法。[Claims] In(Al_
xGa_1_-_x) As (0<x≦1) layer and InGa
When selectively etching the As layer, first, the InGaAs layer is etched using a dry etching method to form In(Al_xGa_1_-_x)As(0<x≦
1) Stop when reaching the In(Al_xGa_1_-_x) As(0
<x≦1) A method for manufacturing a high-speed semiconductor device, comprising the step of etching a layer.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP21505586A JPH0628314B2 (en) | 1986-09-13 | 1986-09-13 | High-speed semiconductor device manufacturing method |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP21505586A JPH0628314B2 (en) | 1986-09-13 | 1986-09-13 | High-speed semiconductor device manufacturing method |
Publications (2)
Publication Number | Publication Date |
---|---|
JPS6372158A true JPS6372158A (en) | 1988-04-01 |
JPH0628314B2 JPH0628314B2 (en) | 1994-04-13 |
Family
ID=16666014
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP21505586A Expired - Fee Related JPH0628314B2 (en) | 1986-09-13 | 1986-09-13 | High-speed semiconductor device manufacturing method |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPH0628314B2 (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH04101430A (en) * | 1990-08-20 | 1992-04-02 | Matsushita Electric Ind Co Ltd | Heterojunction bipolar transistor and manufacture thereof |
US5648294A (en) * | 1989-11-29 | 1997-07-15 | Texas Instruments Incorp. | Integrated circuit and method |
US5837617A (en) * | 1993-04-30 | 1998-11-17 | Fujitsu Limited | Heterojunction compound semiconductor device and method of manufacturing the same |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH07305704A (en) * | 1994-05-12 | 1995-11-21 | Hasegawa Kogyosho:Kk | Wooden handle fixing wedge |
-
1986
- 1986-09-13 JP JP21505586A patent/JPH0628314B2/en not_active Expired - Fee Related
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5648294A (en) * | 1989-11-29 | 1997-07-15 | Texas Instruments Incorp. | Integrated circuit and method |
JPH04101430A (en) * | 1990-08-20 | 1992-04-02 | Matsushita Electric Ind Co Ltd | Heterojunction bipolar transistor and manufacture thereof |
US5837617A (en) * | 1993-04-30 | 1998-11-17 | Fujitsu Limited | Heterojunction compound semiconductor device and method of manufacturing the same |
US6153897A (en) * | 1993-04-30 | 2000-11-28 | Fujitsu Limited | Heterojunction compound semiconductor device and method of manufacturing the same |
Also Published As
Publication number | Publication date |
---|---|
JPH0628314B2 (en) | 1994-04-13 |
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