JP2513835B2 - Semiconductor device - Google Patents

Semiconductor device

Info

Publication number
JP2513835B2
JP2513835B2 JP1098110A JP9811089A JP2513835B2 JP 2513835 B2 JP2513835 B2 JP 2513835B2 JP 1098110 A JP1098110 A JP 1098110A JP 9811089 A JP9811089 A JP 9811089A JP 2513835 B2 JP2513835 B2 JP 2513835B2
Authority
JP
Japan
Prior art keywords
capacitor
substrate
ground
hole
via hole
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 - Lifetime
Application number
JP1098110A
Other languages
Japanese (ja)
Other versions
JPH02276269A (en
Inventor
恭一 石井
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.)
Fujitsu Ltd
Original Assignee
Fujitsu Ltd
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 Fujitsu Ltd filed Critical Fujitsu Ltd
Priority to JP1098110A priority Critical patent/JP2513835B2/en
Publication of JPH02276269A publication Critical patent/JPH02276269A/en
Application granted granted Critical
Publication of JP2513835B2 publication Critical patent/JP2513835B2/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/42Wire connectors; Manufacturing methods related thereto
    • H01L2224/44Structure, shape, material or disposition of the wire connectors prior to the connecting process
    • H01L2224/45Structure, shape, material or disposition of the wire connectors prior to the connecting process of an individual wire connector
    • H01L2224/45001Core members of the connector
    • H01L2224/4501Shape
    • H01L2224/45012Cross-sectional shape
    • H01L2224/45014Ribbon connectors, e.g. rectangular cross-section
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/42Wire connectors; Manufacturing methods related thereto
    • H01L2224/47Structure, shape, material or disposition of the wire connectors after the connecting process
    • H01L2224/48Structure, shape, material or disposition of the wire connectors after the connecting process of an individual wire connector
    • H01L2224/484Connecting portions
    • H01L2224/4847Connecting portions the connecting portion on the bonding area of the semiconductor or solid-state body being a wedge bond
    • H01L2224/48472Connecting portions the connecting portion on the bonding area of the semiconductor or solid-state body being a wedge bond the other connecting portion not on the bonding area also being a wedge bond, i.e. wedge-to-wedge
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/42Wire connectors; Manufacturing methods related thereto
    • H01L2224/47Structure, shape, material or disposition of the wire connectors after the connecting process
    • H01L2224/49Structure, shape, material or disposition of the wire connectors after the connecting process of a plurality of wire connectors
    • H01L2224/491Disposition
    • H01L2224/4911Disposition the connectors being bonded to at least one common bonding area, e.g. daisy chain
    • H01L2224/49111Disposition the connectors being bonded to at least one common bonding area, e.g. daisy chain the connectors connecting two common bonding areas, e.g. Litz or braid wires
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/0001Technical content checked by a classifier
    • H01L2924/00014Technical content checked by a classifier the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details

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  • Semiconductor Integrated Circuits (AREA)

Description

【発明の詳細な説明】 〔概要〕 半導体装置内のキャパシタの接地構造,特にMMIC(Mo
nolithic Microwave IC)のMIM(Metal Insulator Meta
l)構造キャパシタの接地構造に関し, 低接地インダクタンス,小占有面積の特徴を有するバ
イア孔方式によって機械的なストレスフリーのキャパシ
タ接地構造を得ることを目的とし, 基板上に順に積層された下部電極,誘電体膜,上部電
極で構成されるキャパシタと,該基板の下側に接地電位
に接続される接地導電層とを有し,該基板は該キャパシ
タの下側に貫通孔が形成され,該下部電極は該貫通孔を
通じて該接地電極層と電気的に接続され,該誘電体膜及
び該上部電極は該貫通孔に対応する部分が欠如されたパ
ターンに形成されているように構成する。
DETAILED DESCRIPTION [Overview] The grounding structure of a capacitor in a semiconductor device, especially MMIC (Mo
nolithic Microwave IC) MIM (Metal Insulator Meta
l) Regarding the grounding structure of the structural capacitor, the purpose is to obtain a mechanical stress-free capacitor grounding structure by the via hole method, which has the characteristics of low grounding inductance and small occupying area. A capacitor having a dielectric film and an upper electrode, and a ground conductive layer connected to a ground potential on the lower side of the substrate, the substrate having a through hole formed on the lower side of the capacitor, The electrode is electrically connected to the ground electrode layer through the through hole, and the dielectric film and the upper electrode are formed in a pattern lacking a portion corresponding to the through hole.

〔産業上の利用分野〕[Industrial applications]

本発明は半導体装置内のキャパシタの接地構造,特に
MMICのMIM構造キャパシタの接地構造に関する。
The present invention relates to a grounding structure for a capacitor in a semiconductor device, especially
The grounding structure of the MIM structure capacitor of MMIC.

半絶縁性(SI−)GaAs基板を用いたMMICにはMIM構造
の平行平板型キャパシタが多く用いられている。
Parallel plate capacitors of MIM structure are often used for MMIC using semi-insulating (SI-) GaAs substrate.

本発明は,MIM構造のキャパシタの低インダクタンスの
高周波接地構造として使用できる。
INDUSTRIAL APPLICABILITY The present invention can be used as a low-inductance high-frequency grounding structure for a MIM structure capacitor.

〔従来の技術〕[Conventional technology]

基板として,例えばSI−GaAs基板を用いたMMICにおい
ては,MIM構造のキャパシタが随所に用いられている。
In MMICs that use SI-GaAs substrates, for example, MIM structure capacitors are used everywhere.

このキャパシタは,回路によりキャパシタの片側を接
地するものも多数ある。
Many of these capacitors have one side grounded by a circuit.

この場合の高周波接地構造としては,次のものがあ
る。
In this case, there are the following high-frequency grounding structures.

極細ワイヤボンディング方式(又はリボンボンディ
ング方式) 第2図は極細ワイヤボンディングによる接地構造を説
明する平面図である。
Ultrafine Wire Bonding Method (or Ribbon Bonding Method) FIG. 2 is a plan view illustrating a grounding structure by extrafine wire bonding.

図において,絶縁性基板1上に順次キャパシタ下部電
極2,誘電体膜3,キャパシタ上部電極4が形成され,基板
下に形成されている接地(GND)面と下部電極2とを極
細ワイヤ7でボンディングした構造である。
In the figure, a capacitor lower electrode 2, a dielectric film 3, and a capacitor upper electrode 4 are sequentially formed on an insulating substrate 1, and a ground (GND) surface formed under the substrate and the lower electrode 2 are connected by a fine wire 7. It is a bonded structure.

バイア(Via)孔方式 SI−GaAs基板を貫通するバイア孔を開け,この孔を通
じて導通をとり接地する方式である。
Via hole method This is a method in which a via hole is formed through the SI-GaAs substrate, and conduction is provided through this hole for grounding.

第3図はバイア孔方式の接地構造を説明する断面図で
ある。
FIG. 3 is a sectional view for explaining a via hole type grounding structure.

図において,SI−GaAs基板1上に順次キャパシタ下部
電極2,誘電体膜3,キャパシタ上部電極4が形成され,下
部電極2はキャパシタ部より延長した部分で,バイア孔
5内及び基板裏面に形成された接地導電層(接地面)6
に接続される。
In the figure, a capacitor lower electrode 2, a dielectric film 3, and a capacitor upper electrode 4 are sequentially formed on a SI-GaAs substrate 1, and the lower electrode 2 is a portion extending from the capacitor portion and formed in the via hole 5 and on the back surface of the substrate. Ground conductive layer (ground plane) 6
Connected to.

μ波帯,或いはmm波帯においては,キャパシタと接地
電位間に直列に入る接地インダクタンスLGNDは回路の安
定性や高利得を得るためにできるだけ小さいことが望ま
しい。例えば,2GHz帯ではLGND<1nHが必要となる。
In the μ-wave band or mm-wave band, it is desirable that the ground inductance L GND that enters in series between the capacitor and the ground potential be as small as possible in order to obtain circuit stability and high gain. For example, in the 2GHz band, L GND <1nH is required.

そのためと,配置の自由度の点からバイア孔方式がよ
く使われる。
For that reason, the via hole method is often used in terms of the degree of freedom of arrangement.

バイア孔方式でははLGND<0.1nHの低接地インダクタ
ンスが得られる。
With the via hole method, a low ground inductance of L GND <0.1nH can be obtained.

ところが,10GHz以上の周波数帯ではもっと小さい接地
インダクタンスが要求されることと,キャパシタの占有
面積を小さくするために第3図を変形して第4図の構造
のものが用いられるようになった。
However, smaller ground inductance is required in the frequency band of 10 GHz or more, and Fig. 3 is modified to use the structure of Fig. 4 in order to reduce the occupied area of the capacitor.

第4図は従来例の図で,改良型のバイア孔方式の接地
構造を説明する断面図である。
FIG. 4 is a view of a conventional example and is a cross-sectional view for explaining an improved via-hole type grounding structure.

第3図においてはバイア孔をキャパシタの外に設けた
のに対して,第4図の構造はキャパシタの真下に設け
て,キャパシタの配置の占有面積を小さくしている。
In FIG. 3, the via hole is provided outside the capacitor, whereas in the structure of FIG. 4, the via hole is provided directly below the capacitor to reduce the area occupied by the capacitor.

〔発明が解決しようとする課題〕[Problems to be Solved by the Invention]

しかしながら,このような構造を持ったチップを,AuS
n又はAuGe等のろう材を用いてステージにボンディング
する際に,バイア孔内の接地導電層(金あるいは銀メッ
キ層)6がろう材と溶融し,凝固する際に機械的なスト
レスが発生し,キャパシタ部を膨らませたり凹ませたり
して変形させ,誘電体(Si3N4,又はSiO2)層にクラック
を発生させ,そのクラックに金属が侵入してキャパシタ
を短絡させ,或いは動作中に短絡させたりする事故が生
ずることがわかった。
However, a chip with such a structure is
When bonding to the stage using a brazing material such as n or AuGe, the ground conductive layer (gold or silver plating layer) 6 in the via hole melts with the brazing material and mechanical stress occurs when it solidifies. , The capacitor part is deformed by swelling or denting, and cracks are generated in the dielectric (Si 3 N 4 or SiO 2 ) layer, and metal penetrates into the cracks to short-circuit the capacitor, or during operation. It turns out that an accident such as a short circuit occurs.

本発明は低接地インダクタンス,小占有面積の特徴を
有するバイア孔方式によって機械的なストレスフリーの
キャパシタ接地構造を得ることを目的とする。
It is an object of the present invention to obtain a mechanical stress-free capacitor grounding structure by a via hole method having the features of low grounding inductance and small occupied area.

〔課題を解決するための手段〕[Means for solving the problem]

上記課題の解決は,基板上に順に積層された下部電
極,誘電体膜,上部電極で構成されるキャパシタと,該
基板の下側に接地電位に接続される接地導電層とを有
し,該基板は該キャパシタの下側に貫通孔が形成され,
該下部電極は該貫通孔を通じて該接地導電層と電気的に
接続され,該誘電体膜及び該上部電極は該貫通孔に対応
する部分が欠如されたパターンに形成されている半導体
装置により達成される。
A solution to the above problem is to have a capacitor composed of a lower electrode, a dielectric film, and an upper electrode, which are sequentially laminated on a substrate, and a ground conductive layer connected to a ground potential on the lower side of the substrate, The substrate has a through hole formed under the capacitor,
The lower electrode is electrically connected to the ground conductive layer through the through hole, and the dielectric film and the upper electrode are formed by a semiconductor device in which a portion corresponding to the through hole is formed in a pattern. It

〔作用〕[Action]

本発明は,ストレスが発生するバイア孔上部にはキャ
パシタ構造を形成しないで下部電極のみを残して接地接
続を可能にすることにより,チップのろう付けの際のス
トレスを緩和して,製造歩留の低下と素子の信頼性の低
下を防止するようにしたものである。
The present invention alleviates the stress at the time of brazing a chip by forming a capacitor structure above the via hole where stress is generated and leaving only the lower electrode to allow the ground connection, thereby reducing the manufacturing yield. To prevent the deterioration of the device and the reliability of the device.

〔実施例〕〔Example〕

第1図(1),(2)は本発明の一実施例によるバイ
ア孔方式の接地構造を説明する断面図と平面図である。
1 (1) and 1 (2) are a sectional view and a plan view for explaining a via hole type grounding structure according to an embodiment of the present invention.

図において,厚さ75μmのSI−GaAs基板1上に順次キ
ャパシタ下部電極2,誘電体膜3,キャパシタ上部電極4が
形成され,下部電極2はキャパシタ部分でバイア孔5内
及び基板裏面に形成された接地導電層6に接続される。
In the figure, a capacitor lower electrode 2, a dielectric film 3, and a capacitor upper electrode 4 are sequentially formed on a SI-GaAs substrate 1 having a thickness of 75 μm, and the lower electrode 2 is formed in the via hole 5 and the back surface of the substrate at the capacitor portion. Connected to the ground conductive layer 6.

誘電体膜3,キャパシタ上部電極4はバイア孔5の上部
で欠如したパターンに形成する。
The dielectric film 3 and the capacitor upper electrode 4 are formed in a pattern that is missing above the via hole 5.

ここで,キャパシタは 下部電極2が厚さ0.3μmのAuGeNiAu膜, 誘電体膜3が厚さ0.2μmのSi3N4膜, 上部電極4が厚さ2μmのAuメッキ膜 で構成される。Here, in the capacitor, the lower electrode 2 is composed of a AuGeNiAu film having a thickness of 0.3 μm, the dielectric film 3 is a Si 3 N 4 film having a thickness of 0.2 μm, and the upper electrode 4 is composed of an Au plating film having a thickness of 2 μm.

又,接地導電層6は厚さ15μmのAuメッキ膜で形成さ
れる。
The ground conductive layer 6 is formed of a 15 μm thick Au plating film.

前記したように,キャパシタ接地構造において考慮し
なければならない点は次のように要約することができ
る。
As described above, the points to be considered in the capacitor grounding structure can be summarized as follows.

キャパシタは低接地インダクタンス,低直列抵抗で
あること。
The capacitor should have low ground inductance and low series resistance.

チップ上のキャパシタ配置に自由度があること。 There is flexibility in the placement of capacitors on the chip.

キャパシタ配置の占有面積が小さいこと。 The area occupied by the capacitor is small.

この例においては,上記の考慮点およびは第3図
と第4図の構造の中間位の値となるが,キャパシタを短
絡させる致命的な欠陥を生じることはない。
In this example, the above-mentioned considerations and are intermediate values of the structures of FIGS. 3 and 4, but do not cause a fatal defect that short-circuits the capacitor.

ろう材にAuSnを用いてチップのろう付けを行ったとこ
ろ,多数試料についてキャパシタの短絡は全然発生しな
かった。従って,製造歩留の向上と素子の信頼性向上に
有効であることが確かめられた。又,接地インダクタン
スは0.05nHと低い値が得られた。
When AuSn was used as the brazing material, the chips were brazed and no short circuit of the capacitors occurred for many samples. Therefore, it was confirmed to be effective in improving the manufacturing yield and improving the reliability of the device. In addition, the ground inductance was as low as 0.05nH.

第5図(1),(2)は本発明を適用したMMICの一例
を示す平面図と回路図である。
5 (1) and 5 (2) are a plan view and a circuit diagram showing an example of an MMIC to which the present invention is applied.

このMMICは1〜8GHz広帯域2段増幅器(利得≒8dB)
で,チップサイズ1.3mm×1.7mmのSI−GaAs基板に形成さ
れ,キャパシタC2,C4に本発明が適用されている。
This MMIC is a 1-8 GHz wide band 2-stage amplifier (gain ≈ 8 dB)
Thus, the present invention is applied to capacitors C 2 and C 4 which are formed on a SI-GaAs substrate having a chip size of 1.3 mm × 1.7 mm.

GaAs MES FET Q1,Q2はイオン注入によりチャネル領域
を形成し,抵抗RもSI−GaAs基板にイオン注入して抵抗
体としている。回路図の矩形はマイクロストリップ線路
を表している。
The GaAs MES FETs Q 1 and Q 2 form a channel region by ion implantation, and the resistor R is also ion-implanted into the SI-GaAs substrate to form a resistor. The rectangle in the circuit diagram represents the microstrip line.

キャパシタC2は1個のバイア孔,キャパシタC4は2個
のバイア孔5を経由して,接地端子VGGに接続されてい
る。
The capacitor C 2 is connected to the ground terminal V GG via one via hole and the capacitor C 4 via two via holes 5.

〔発明の効果〕〔The invention's effect〕

以上説明したように本発明によれば,低接地インダク
タンス,小占有面積の特徴を有するバイア孔方式によっ
て機械的なストレスフリーのキャパシタ接地構造を得る
ことができる。
As described above, according to the present invention, it is possible to obtain a mechanical stress-free capacitor ground structure by the via hole method having the features of low ground inductance and small occupied area.

従って,MMICの製造歩留と信頼性を向上することがで
きる。
Therefore, the manufacturing yield and reliability of MMIC can be improved.

【図面の簡単な説明】[Brief description of drawings]

第1図(1),(2)は本発明の一実施例によるバイア
孔方式の接地構造を説明する断面図と平面図, 第2図は極細ワイヤボンディングによる接地構造を説明
する平面図, 第3図はバイア孔方式の接地構造を説明する断面図, 第4図は従来例の図で,改良型のバイア孔方式の接地構
造を説明する断面図, 第5図(1),(2)は本発明を適用したMMICの一例を
示す平面図と回路図である。 図において, 1は基板でSI−GaAs基板, 2はキャパシタ下部電極, 3は誘電体膜, 4はキャパシタ上部電極, 5はバイア孔, 6は接地導電層 である。
1 (1) and 1 (2) are a sectional view and a plan view for explaining a via hole type grounding structure according to an embodiment of the present invention, and FIG. 2 is a plan view for explaining a grounding structure by extra fine wire bonding. FIG. 3 is a cross-sectional view illustrating a via-hole grounding structure, FIG. 4 is a view illustrating a conventional example, and a cross-sectional view illustrating an improved via-hole grounding structure, FIG. 5 (1), (2) FIG. 2A is a plan view and a circuit diagram showing an example of an MMIC to which the present invention is applied. In the figure, 1 is a substrate, an SI-GaAs substrate, 2 is a capacitor lower electrode, 3 is a dielectric film, 4 is a capacitor upper electrode, 5 is a via hole, and 6 is a ground conductive layer.

Claims (1)

(57)【特許請求の範囲】(57) [Claims] 【請求項1】基板上に順に積層された下部電極,誘電体
膜,上部電極で構成されるキャパシタと, 該基板の下側に接地電位に接続される接地導電層とを有
し, 該基板は該キャパシタの下側に貫通孔が形成され, 該下部電極は該貫通孔を通じて該接地導電層と電気的に
接続され, 該誘電体膜及び該上部電極は該貫通孔に対応する部分が
欠如されたパターンに形成されていることを特徴とする
半導体装置。
1. A substrate comprising a lower electrode, a dielectric film, and an upper electrode, which are sequentially stacked on a substrate, and a ground conductive layer connected to a ground potential on the lower side of the substrate. A through hole is formed under the capacitor, the lower electrode is electrically connected to the ground conductive layer through the through hole, and the dielectric film and the upper electrode lack a portion corresponding to the through hole. A semiconductor device, which is formed in a patterned pattern.
JP1098110A 1989-04-18 1989-04-18 Semiconductor device Expired - Lifetime JP2513835B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP1098110A JP2513835B2 (en) 1989-04-18 1989-04-18 Semiconductor device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP1098110A JP2513835B2 (en) 1989-04-18 1989-04-18 Semiconductor device

Publications (2)

Publication Number Publication Date
JPH02276269A JPH02276269A (en) 1990-11-13
JP2513835B2 true JP2513835B2 (en) 1996-07-03

Family

ID=14211189

Family Applications (1)

Application Number Title Priority Date Filing Date
JP1098110A Expired - Lifetime JP2513835B2 (en) 1989-04-18 1989-04-18 Semiconductor device

Country Status (1)

Country Link
JP (1) JP2513835B2 (en)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5208726A (en) * 1992-04-03 1993-05-04 Teledyne Monolithic Microwave Metal-insulator-metal (MIM) capacitor-around-via structure for a monolithic microwave integrated circuit (MMIC) and method of manufacturing same
JP2006173595A (en) * 2004-11-22 2006-06-29 Matsushita Electric Ind Co Ltd Semiconductor integrated circuit device and on-board radar system using the same
CN105280727A (en) * 2015-11-06 2016-01-27 中国电子科技集团公司第十三研究所 Microwave internal matching power transistor matching capacitor and manufacturing method thereof

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