JPH01150867A - Method and apparatus for adjusting capacity measuring bridge - Google Patents
Method and apparatus for adjusting capacity measuring bridgeInfo
- Publication number
- JPH01150867A JPH01150867A JP63277539A JP27753988A JPH01150867A JP H01150867 A JPH01150867 A JP H01150867A JP 63277539 A JP63277539 A JP 63277539A JP 27753988 A JP27753988 A JP 27753988A JP H01150867 A JPH01150867 A JP H01150867A
- Authority
- JP
- Japan
- Prior art keywords
- preamplifier
- circuit
- sample
- input
- tuning
- 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.)
- Pending
Links
- 238000000034 method Methods 0.000 title claims description 15
- 238000005259 measurement Methods 0.000 claims description 12
- 230000035945 sensitivity Effects 0.000 description 5
- 239000003990 capacitor Substances 0.000 description 4
- 230000005669 field effect Effects 0.000 description 4
- 238000004804 winding Methods 0.000 description 3
- 102100031920 Dihydrolipoyllysine-residue succinyltransferase component of 2-oxoglutarate dehydrogenase complex, mitochondrial Human genes 0.000 description 2
- 101000992065 Homo sapiens Dihydrolipoyllysine-residue succinyltransferase component of 2-oxoglutarate dehydrogenase complex, mitochondrial Proteins 0.000 description 2
- 230000003321 amplification Effects 0.000 description 2
- 238000004458 analytical method Methods 0.000 description 2
- 238000001773 deep-level transient spectroscopy Methods 0.000 description 2
- 238000003199 nucleic acid amplification method Methods 0.000 description 2
- 239000004065 semiconductor Substances 0.000 description 2
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000005457 optimization Methods 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R27/00—Arrangements for measuring resistance, reactance, impedance, or electric characteristics derived therefrom
- G01R27/02—Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant
- G01R27/26—Measuring inductance or capacitance; Measuring quality factor, e.g. by using the resonance method; Measuring loss factor; Measuring dielectric constants ; Measuring impedance or related variables
- G01R27/2605—Measuring capacitance
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Measurement Of Resistance Or Impedance (AREA)
- Measuring Instrument Details And Bridges, And Automatic Balancing Devices (AREA)
- Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)
- Testing Of Individual Semiconductor Devices (AREA)
Abstract
(57)【要約】本公報は電子出願前の出願データであるた
め要約のデータは記録されません。(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.
Description
【発明の詳細な説明】
発明の応用分野
この発明の応用分野は、容量測定ブリフジを用いた微小
容量変化の測定、主に半導体の容量分析である。特に有
利な利点は、所謂走査ＤＬＴＳ法の場合に使用される。DETAILED DESCRIPTION OF THE INVENTION Field of Application of the Invention The field of application of the present invention is the measurement of minute capacitance changes using a capacitance measurement brifuge, mainly capacitance analysis of semiconductors. A particularly advantageous advantage is used in the case of the so-called scanning DLTS method.
従巣ｉ術の特徴
微小容量又は容量の変化を高感度で測定するには、測定
ブリッジの種々の方式が提唱され、また実際に採用され
ている。半導体の容量分析で生じる高度な要求は、東独
特許第２０２７６４号公報に記載されている原理の装置
が適している。この装置では、試料の一端に交流電圧を
印加し、他端には、この試料が測定周波数に同調させて
ある共振回路の一部で、前置増幅回路の入力容量が測定
周波数に同調させてある第二共振回路に対するインダク
タンスで補償される（「並列共振回路」）ように、試料
の導電量の変化に関連する交流電流の変化を試料を経由
して検証している。この装置の同調の問題は、二つの部
分から成り、それ等は、一方では試料の容量の平衡と損
失成分の補償である−即ち、試料を含めた共振回路を前
置増幅器の最低高周波電圧で調整すること−と、他方で
は装置の感度と高周波（ＨＦ）信号の位相位置に影響を
与える前置増幅器の第二共振回路の微調である。この回
路の調整状態は、試料自体の容量から影響を受けないが
、大地に対する試料の接続端子の幾何学的に制約される
種々の擾乱容量によって影響を受けるので、微調が必要
である。試料を交換する場合、不利が生じるのは、−測
定の初めに粗く調整した前置増幅器の入力回路から出発
して一試料回路を新しい試料の容量と損失成分に関して
調整し、その後前置増幅器の入力回路を微調する必要が
ある。通常の同調方法では、試料を交換した直後（殊に
中位及び大きい試料容量の場合）非常にシャープに目立
つＨＦ信号の同調ミニマムのため−即ち、未だ同調をと
っていない試料回路の場合−実際上全ＨＦ電圧が前置増
幅器の入力端に印加して、この回路を過剰制御すると点
にある。これには、ＨＦ電圧及び／又はＨＦ増幅度を減
少させて対処する必要がある。このことは、試料回路を
同調できる第一の前提である。Characteristics of the Follow-up Bridge Method In order to measure minute capacitances or changes in capacitance with high sensitivity, various types of measurement bridges have been proposed and actually employed. For the high demands arising in capacitance analysis of semiconductors, an apparatus based on the principle described in East German Patent No. 202,764 is suitable. In this device, an alternating voltage is applied to one end of the sample, and at the other end this sample is part of a resonant circuit tuned to the measurement frequency, and the input capacitance of the preamplifier circuit is tuned to the measurement frequency. Changes in the alternating current associated with changes in the conductivity of the sample are verified via the sample, as compensated by the inductance for a certain second resonant circuit ("parallel resonant circuit"). The problem of tuning this device consists of two parts: on the one hand, balancing the capacitance of the sample and compensating for the loss component - i.e., connecting the resonant circuit containing the sample to the lowest high-frequency voltage of the preamplifier. and, on the other hand, the fine tuning of the second resonant circuit of the preamplifier, which influences the sensitivity of the device and the phase position of the high frequency (HF) signal. The adjustment state of this circuit is not affected by the capacitance of the sample itself, but is affected by various disturbance capacitances constrained by the geometry of the connection terminal of the sample to ground, and therefore requires fine adjustment. Disadvantages arise when changing samples: - starting from a coarsely adjusted input circuit of the preamplifier at the beginning of the measurement, one sample circuit is adjusted with respect to the capacitance and loss components of the new sample; It is necessary to fine-tune the input circuit. With conventional tuning methods, the tuning minimum of the HF signal is very sharply noticeable immediately after changing the sample (especially for medium and large sample volumes) - i.e. for sample circuits that have not yet been tuned - in practice. There is a point when a full HF voltage is applied to the input of the preamplifier to over-control this circuit. This needs to be addressed by reducing the HF voltage and/or HF amplification. This is the first prerequisite for being able to tune the sample circuit.
しかしながら、この部分的な問題を解決する場合の主要
な問題は、従来の並列ブリッジ装置に存在しているが、
ＨＦ信号が非同調状態の調整状態に依存しない点にある
。それ故、同調ミニマムの近くを見出すために、従来直
観的な処置が必要であった。However, the main problem in solving this partial problem exists in traditional parallel bridge devices;
The point is that the HF signal does not depend on the adjustment state of the out-of-tune state. Therefore, conventionally an intuitive procedure was required to find the vicinity of the tuning minimum.
試料回路の同調が大体とられていると、前置増幅器の入
力回路をＨＦ振幅又は最適位相位置に微調する。これは
、従来技術では大地に対して前置増幅入力端のインダク
タンスの手動調整によって行われる。Once the sample circuit is roughly tuned, fine tune the preamplifier input circuit to the HF amplitude or optimum phase position. This is done in the prior art by manual adjustment of the inductance of the preamplifier input with respect to ground.
この処置は、時間を非常に浪費し、操作に非常な費用を
要し、更に大変な実験上の経験が前提になる。走査ＤＬ
ＴＳ法の様な特別なりＬＴＳ変形種の場合、更にこの測
定装置は全←簡単には手の届くものではない。手動調整
は一部じて実現できる時−ここでは支持できない構造上
の経費が必要になる。This procedure is very time consuming, very expensive to operate, and also requires extensive experimental experience. Scan DL
In the case of special LTS variants such as the TS method, moreover, this measuring equipment is not easily accessible. Manual adjustment can only be realized in some cases - this requires unsustainable structural outlays.
発明の目的
この発明の目的は、簡単で、間違いが全くなく、操作を
早く行え、機械的には到達できない測定問題の場合でも
測定ブリッジを導入でき、同調方法とそれを実現するた
めに使用される並列共振配置の容量測定ブリッジ用の装
置を提供することにある。OBJECTS OF THE INVENTION The objects of the invention are to provide a simple, error-free and fast operation, to introduce a measuring bridge even in the case of mechanically inaccessible measurement problems, to provide a tuning method and the method used to realize it. The object of the present invention is to provide a device for a capacitive measuring bridge in a parallel resonant arrangement.
発明の詳細な説明
この発明の課題は、同調方法とこの方法を実現するため
に使用される並列共振配置にした容量測定ブリッジに対
する装置を開発することにあり、この装置は機械的な部
材を使用しなく、同調状態に一義的に依存する信号によ
って同調を可能にし、ブリッジのＨＦ電圧及び／又はＨ
Ｆ増幅度の経時変化させない。DETAILED DESCRIPTION OF THE INVENTION The object of the invention is to develop a tuning method and a device for a capacitive measuring bridge in parallel resonant arrangement used to realize this method, which device uses mechanical components. HF voltage of the bridge and/or H
Do not allow the F amplification degree to change over time.
上記の課題は、この発明により以下のように解決されて
いる。即ち、制御可能な抵抗に印加した第一制御電圧に
よって、前置増幅器の入力回路の良さ、従ってインピー
ダンスを低下させ、次いで通常の方法で試料回路の同調
をとり、それに基づき、第一制御電圧によって前置増幅
器の入力回路の良さを再び上昇させ、それに基づき容量
ダイオードに印加する第二制御電圧によって前置増幅器
の入力回路の共振周波数を完全に同調させるまで可変す
ることによる。The above problems are solved by the present invention as follows. That is, the input circuit, and therefore the impedance, of the preamplifier is lowered by a first control voltage applied to a controllable resistor, and then the sample circuit is tuned in the usual way, and on that basis the first control voltage is applied. By increasing the quality of the input circuit of the preamplifier again and thereby varying the resonant frequency of the input circuit of the preamplifier by means of a second control voltage applied to the capacitive diode until it is completely tuned.
前置増幅器の入力回路の良さを低減させることによって
、同調ミニマムのシャープさを大幅に低減させ、それに
よって、試料の同調の主要な問題、即ちＨＦ信号が正確
な同調外の調整状態に無関係であることが解決される。By reducing the quality of the preamplifier input circuit, the sharpness of the tuning minimum is significantly reduced, thereby solving the main problem of sample tuning, namely that the HF signal is independent of the tuning state outside of precise tuning. Something is resolved.
従って、この装置は前記課題の解決によって、簡単で迅
速な方法で低減された測定装置の感度−例えば、大きな
容量変化の試料を測定するため−を調整するのに適し、
従って測定ブリッジの導入範囲を拡大させるのに通して
いる。This device is therefore suitable for adjusting the reduced sensitivity of a measuring device, for example for measuring samples with large capacitance changes, in a simple and quick manner, by solving the above-mentioned problems;
Therefore, it is possible to expand the range of implementation of the measuring bridge.
制御可能な抵抗として、ＦＥＴを選ぶことができる。こ
の発明による解決策の有利な構成では、通常の測定ブリ
ッジで試料に電圧パルスを印加している間とその直後前
置増幅器の入力端を短絡し、それ以外では動作させない
機能を満たすＦＥＴである。A FET can be chosen as the controllable resistor. In an advantageous configuration of the solution according to the invention, an FET fulfills the function of short-circuiting the input of the preamplifier during and immediately after applying a voltage pulse to the sample with a conventional measuring bridge, and otherwise not operating it. .
実施例
図面には、この発明による装置の効果的な実現が示しで
ある。ＨＦ）ランス２は、強結合を達成するため、ＨＦ
発生器１に結合した並列接続−次巻線と分離した複数の
二次巻線を有する四重バルーン・トランスとして形成し
である。試料３に対するバイアス電圧は、必要なＨＦ短
絡（高周波成分に対する短絡）を出力端で実現させるイ
ンピーダンス変換器４を経由して導入される。容量ダイ
オード５には立ち上がりの急なパルスを印加する必要が
ないので、そこではＨＦ短絡はコンデンサ６によって実
現される。回路インダクタンス７に対する対応する接続
は直接大地に置かれる。損失部分を補償する二次巻線は
、電子制御可能な抵抗８によって試料回路に並列な１８
０ ”位相のずれたＨＦ電流がＨＦ前置増幅器９の共通
の接続端子に導入されるように接続される。その前置増
幅器の入力容量と大地に対する擾乱容量は第二インダク
タンス１０によって補償される。The exemplary drawings show an advantageous realization of the device according to the invention. HF) Lance 2 is HF to achieve strong coupling.
The parallel connection coupled to the generator 1 is configured as a quadruple balloon transformer with a primary winding and a plurality of separate secondary windings. The bias voltage for the sample 3 is introduced via an impedance converter 4 which implements the necessary HF short circuit (short circuit for high frequency components) at the output end. Since there is no need to apply a sharp rising pulse to the capacitive diode 5, the HF short circuit is realized there by the capacitor 6. The corresponding connection to circuit inductance 7 is placed directly to earth. The secondary winding compensating for the loss part is connected by an electronically controllable resistor 8 parallel to the sample circuit.
0" is connected such that the out-of-phase HF current is introduced into the common connection terminal of the HF preamplifier 9. The input capacitance of that preamplifier and the disturbance capacitance to ground are compensated by a second inductance 10. .
この発明によれば、前置増幅器の入力端と大地の間には
、第一制御電圧Ｕ４によって制御される電界効果トラン
ジスタ１１と第二制御電圧Ｕ５に連結する容量ダイオー
ド１２がある。制御電圧Ｕ５の接続は、通常の方法でコ
ンデンサ１３を用いて大地に対して高周波的に短絡して
いる。制御電圧Ｕ４は、パルスの間と直後のある期間公
知の方法で前置増幅器の入力端で実際上短絡が生じるよ
うに選定される。パルスの後のＤＬＴＳ測定期間及び調
整過程の間、この発明によればそれぞれ測定を問題にす
る時と同調を問題にする時に望ましい装置の感度を達成
するようにＵ４を調整している。電界効果トランジスタ
１１が高抵抗で、前置増幅器の回路が高い良さを有する
ようにＵ４を選べば、この発明によれば同調電圧Ｕ５を
介して装置の感度又は信号の位相位置を最適化できる。According to the invention, between the input of the preamplifier and ground there is a field effect transistor 11 controlled by a first control voltage U4 and a capacitive diode 12 coupled to a second control voltage U5. The connection of the control voltage U5 is a high-frequency short-circuit to ground using a capacitor 13 in the usual manner. The control voltage U4 is selected in such a way that a practical short-circuit occurs at the input of the preamplifier in a known manner for a period of time during and immediately after the pulses. During the DLTS measurement period after the pulse and during the adjustment process, the invention adjusts U4 to achieve the desired instrument sensitivity when measuring and tuning, respectively. If U4 is chosen such that the field-effect transistor 11 has a high resistance and the preamplifier circuit has a high quality, the invention allows optimization of the sensitivity of the device or the phase position of the signal via the tuning voltage U5.
添付図は、この発明による容量測定ブリッジ用の同調回
路図。
引用記号：
■・・・ＨＦ信号発生器、
２・・・４重ＨＦ）ランス、
３・・・試料、
４・・・インピーダンス変換器、
５・・・容量ダイオード、
６・・・コンデンサ、
７・・・回路インピーダンス、
８・・・制御可能な抵抗、
９・・・ＨＦ前置増幅器、
１０・・・補償インダクタンス、
１１・・・電界効果トランジスタ、
１２・・・容量ダイオード、
１３・・・コンデンサ、
Ｕｌ・・・試料バイアス電圧、
Ｕ２・・・制御可能な抵抗８の制御電圧、Ｕ３・・−電
界効果トランジスタ１１の制御電圧、Ｕ５・・・容量ダ
イオードＩ２０制御電圧、ＵＡ・・・ＨＦ出力信号。The attached figure is a tuning circuit diagram for a capacitive measuring bridge according to the invention. Reference symbols: ■...HF signal generator, 2...quadruple HF) lance, 3...sample, 4...impedance converter, 5...capacitance diode, 6...capacitor, 7 ...Circuit impedance, 8.Controllable resistance, 9.HF preamplifier, 10.Compensation inductance, 11..Field effect transistor, 12..Capacitance diode, 13.. Capacitor, Ul...sample bias voltage, U2...control voltage of controllable resistor 8, U3...-control voltage of field effect transistor 11, U5...control voltage of capacitance diode I20, UA...HF output signal.
Claims (1)
であり、前置増幅器回路の入力容量がこの前置増幅器入
力端と大地の間にあって、測定周波数に同調させてある
共振回路に対するインダクタンスを用いて補償される容
量測定ブリッジの同調方法において、試料を設置した後
、先ず制御可能な抵抗に印加される第一制御電圧を介し
て、前置増幅器の入力回路の良さとインピーダンスとが
低減され、次いで公知の方法で試料回路の同調をとり、
それに基づき第一制御電圧によって前置増幅器の入力回
路の良さを低減させ、それに基づき、容量ダイオードに
印加する第二制御電圧によって前置増幅器の入力回路の
共鳴周波数が完全に同調に達するまで可変されることを
特徴とする容量測定ブリッジの同調方法。 ２、試料が測定周波数に同調させてある共振回路の一部
であり、前置増幅器回路の入力容量がこの前置増幅器入
力端と大地の間にあって、測定周波数に同調させてある
共振回路に対するインダクタンスを用いて補償される容
量測定ブリッジの同調方法において、前置増幅器入力端
と大地の間には、制御可能な抵抗と容量ダイオードが並
列接続してあることを特徴とする容量測定ブリッジの同
調方法。 ３、制御可能な抵抗は、ＦＥＴであることを特徴とする
請求項２による同調装置。 ４、制御可能な抵抗は、記載した方式の通常のブリッジ
で前置増幅器入力端の短絡を試料にバイアス電圧パルス
を印加した直後に実現させるＦＥＴであることを特徴と
する請求項３による同調装置。[Claims] 1. The sample is part of a resonant circuit tuned to the measurement frequency, and the input capacitance of the preamplifier circuit is between the preamplifier input terminal and ground, and the sample is tuned to the measurement frequency. In the method of tuning a capacitive measuring bridge compensated using an inductance to a certain resonant circuit, after installing the sample, the input circuit of the preamplifier is first tuned via a first control voltage applied to a controllable resistor. the resistance and impedance are reduced, then the sample circuit is tuned in a known manner,
Based on this, a first control voltage reduces the quality of the input circuit of the preamplifier, and a second control voltage applied to the capacitance diode varies the resonant frequency of the input circuit of the preamplifier until it reaches perfect tuning. A method for tuning a capacitance measuring bridge, characterized in that: 2. The sample is part of a resonant circuit tuned to the measurement frequency, and the input capacitance of the preamplifier circuit is between this preamplifier input and ground, and the inductance for the resonant circuit tuned to the measurement frequency. A method for tuning a capacitive measuring bridge compensated using a capacitive measuring bridge, characterized in that a controllable resistor and a capacitive diode are connected in parallel between the preamplifier input terminal and ground. . 3. Tuning device according to claim 2, characterized in that the controllable resistor is a FET. 4. Tuning device according to claim 3, characterized in that the controllable resistor is a FET, which enables short-circuiting of the preamplifier input with a conventional bridge of the described type immediately after applying a bias voltage pulse to the sample. .
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DD03J/308765-8 | 1987-11-06 | ||
| DD30876587A DD278042A3 (en) | 1987-11-06 | 1987-11-06 | Voting procedure and equipment for capacity measuring bridges |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH01150867A true JPH01150867A (en) | 1989-06-13 |
Family
ID=5593709
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63277539A Pending JPH01150867A (en) | 1987-11-06 | 1988-11-04 | Method and apparatus for adjusting capacity measuring bridge |
Country Status (4)
| Country | Link |
|---|---|
| JP (1) | JPH01150867A (en) |
| DD (1) | DD278042A3 (en) |
| DE (1) | DE3828856A1 (en) |
| GB (1) | GB2212280B (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111103499A (en) * | 2018-10-09 | 2020-05-05 | 长沙理工大学 | Method for measuring ground parameters of power distribution network grounded through arc suppression coil series resistor |
| CN112816790A (en) * | 2021-02-02 | 2021-05-18 | 北京大学 | Quantum capacitance measuring system and measuring method thereof |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6111718A (en) * | 1998-06-08 | 2000-08-29 | Ampex Corporation | Electronic record/play switch with low noise low input impedance preamplifier |
-
1987
- 1987-11-06 DD DD30876587A patent/DD278042A3/en not_active IP Right Cessation
-
1988
- 1988-08-10 GB GB8818946A patent/GB2212280B/en not_active Expired - Lifetime
- 1988-08-25 DE DE3828856A patent/DE3828856A1/en not_active Withdrawn
- 1988-11-04 JP JP63277539A patent/JPH01150867A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111103499A (en) * | 2018-10-09 | 2020-05-05 | 长沙理工大学 | Method for measuring ground parameters of power distribution network grounded through arc suppression coil series resistor |
| CN112816790A (en) * | 2021-02-02 | 2021-05-18 | 北京大学 | Quantum capacitance measuring system and measuring method thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| DE3828856A1 (en) | 1989-05-18 |
| GB2212280A (en) | 1989-07-19 |
| DD278042A3 (en) | 1990-04-25 |
| GB2212280B (en) | 1992-01-08 |
| GB8818946D0 (en) | 1988-09-14 |
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