JPH0469338B2 - - Google Patents
Info
- Publication number
- JPH0469338B2 JPH0469338B2 JP58080887A JP8088783A JPH0469338B2 JP H0469338 B2 JPH0469338 B2 JP H0469338B2 JP 58080887 A JP58080887 A JP 58080887A JP 8088783 A JP8088783 A JP 8088783A JP H0469338 B2 JPH0469338 B2 JP H0469338B2
- Authority
- JP
- Japan
- Prior art keywords
- electrode
- reference electrode
- fet
- sensor
- source
- 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
Links
- 239000000126 substance Substances 0.000 claims description 23
- 229910004298 SiO 2 Inorganic materials 0.000 claims description 9
- 239000000758 substrate Substances 0.000 claims description 6
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims description 2
- 229910052710 silicon Inorganic materials 0.000 claims description 2
- 239000010703 silicon Substances 0.000 claims description 2
- 239000004020 conductor Substances 0.000 claims 1
- 239000012528 membrane Substances 0.000 description 11
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 8
- 150000002500 ions Chemical class 0.000 description 8
- 229910021420 polycrystalline silicon Inorganic materials 0.000 description 8
- 239000010410 layer Substances 0.000 description 6
- 229910002092 carbon dioxide Inorganic materials 0.000 description 4
- 239000001569 carbon dioxide Substances 0.000 description 4
- WABPQHHGFIMREM-UHFFFAOYSA-N lead(0) Chemical compound [Pb] WABPQHHGFIMREM-UHFFFAOYSA-N 0.000 description 3
- 102000004190 Enzymes Human genes 0.000 description 2
- 108090000790 Enzymes Proteins 0.000 description 2
- 229910021607 Silver chloride Inorganic materials 0.000 description 2
- 239000008280 blood Substances 0.000 description 2
- 210000004369 blood Anatomy 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 238000001139 pH measurement Methods 0.000 description 2
- HKZLPVFGJNLROG-UHFFFAOYSA-M silver monochloride Chemical compound [Cl-].[Ag+] HKZLPVFGJNLROG-UHFFFAOYSA-M 0.000 description 2
- 239000002344 surface layer Substances 0.000 description 2
- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Chemical compound NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 description 1
- 239000012491 analyte Substances 0.000 description 1
- 239000004202 carbamide Substances 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- ZOMNIUBKTOKEHS-UHFFFAOYSA-L dimercury dichloride Chemical class Cl[Hg][Hg]Cl ZOMNIUBKTOKEHS-UHFFFAOYSA-L 0.000 description 1
- 239000003792 electrolyte Substances 0.000 description 1
- 230000005669 field effect Effects 0.000 description 1
- 230000010354 integration Effects 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
- G01N27/26—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electrochemical variables; by using electrolysis or electrophoresis
- G01N27/403—Cells and electrode assemblies
- G01N27/414—Ion-sensitive or chemical field-effect transistors, i.e. ISFETS or CHEMFETS
Landscapes
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
- Physics & Mathematics (AREA)
- Biochemistry (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- Engineering & Computer Science (AREA)
- Analytical Chemistry (AREA)
- Molecular Biology (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)
- Measurement Of The Respiration, Hearing Ability, Form, And Blood Characteristics Of Living Organisms (AREA)
Description
【発明の詳細な説明】
〔発明の利用分野〕
本発明は、溶液中の特定化学物質濃度を測定す
る電界効果トランジスタ（FET）化学センサー
に関する。DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a field effect transistor (FET) chemical sensor for measuring the concentration of a specific chemical in a solution.
〔発明の背景〕
従来のFET化学センサーは、飽和カロメル参
照電極と共通するか、あるいは同一チツプ上に
pH測定用センサーと参照電極を平行に並べて使
用するものなどであつた（D.Harame et al，
IEEE IEDM p.467〜470（1981），K.Shimada et
al，Med.＆ Biol Eng.＆ Comput 1980，18，
p.741〜745）。これらは電極としてFET化学セン
サーと参照電極を別々に必要とすることから電極
数が多いこと、あるいはFET化学センサーと参
照電極を並べたものの場合は、広い面積のチツプ
を必要とするなどの問題があつた。BACKGROUND OF THE INVENTION Conventional FET chemical sensors have a saturated calomel reference electrode in common or on the same chip.
A sensor for pH measurement and a reference electrode were used in parallel (D.Harame et al.
IEEE IEDM p.467-470 (1981), K. Shimada et
al, Med. & Biol Eng. & Comput 1980, 18,
p.741-745). These devices require a separate FET chemical sensor and reference electrode as electrodes, resulting in a large number of electrodes, or if the FET chemical sensor and reference electrode are arranged side by side, a chip with a large area is required. It was hot.
本発明の目的は、参照電極のリード線を無くす
ることにより外部からの電気的ノイズを低減し得
るFET化学センサーを提供することにある。
An object of the present invention is to provide a FET chemical sensor that can reduce external electrical noise by eliminating a reference electrode lead wire.
本発明は、シリコン基板上のSiO2層内にソー
ス用電極およびドレイン用電極を設け、上記
SiO2層上にイオン感応膜を設けたFET化学セン
サーにおいて、上記SiO2層上に参照電極を形成
し、上記ソース用電極と上記参照電極とを、上記
SiO2層内において電気的に接続したことを特徴
とする。
The present invention provides a source electrode and a drain electrode in the SiO 2 layer on a silicon substrate, and
In an FET chemical sensor in which an ion-sensitive film is provided on two SiO layers, a reference electrode is formed on the two SiO layers, and the source electrode and the reference electrode are connected to the
It is characterized by electrical connection within the two SiO layers.
本発明のFET化学センサーは、血液自動分析
装置用センサーなどとして用いられ、ゲート部分
上にイオン感応膜を塗布したものは、血液の電解
質イオン（pH，Na+，K+，Cl-）の濃度を測る
ものであり、ウレアーゼ固定化酵素膜を塗布した
ものは、尿素センサーとなる。 The FET chemical sensor of the present invention is used as a sensor for automatic blood analyzers, etc., and the one with an ion-sensitive membrane coated on the gate part measures the concentration of electrolyte ions (pH, Na + , K + , Cl - ) in blood. The sensor coated with a urease-immobilized enzyme membrane becomes a urea sensor.
以下、本発明を実施例により、その構成及び動
作を説明する。
Hereinafter, the configuration and operation of the present invention will be explained using examples.
第１の実施例について述べる。第１図はpH測
定用FETセンサーの平面図を示し、Si基板１上
に参照電極５とFET化学センサーを形成してい
る。第２図に第１図のＡ−Ａの断面図を、第３図
にＢ−Ｂ断面図を示す。FET化学センサー自体
は従来のFET化学センサーの構造をとつており、
基板１としてｐ型Siを用いドレイン２とソース３
にn+拡散層を形成し、チヤンネル部分にｎ形表
面層８を形成したｎチヤンネルデイプリーシヨン
形のFETである。ゲート４にはSiO2１１，Si3N4
１２の膜を形成し、その上にイオン感応膜として
Ta2O5１３を形成している。一方参照電極５は
Ag１５とAgCl１６から成つておりSiO2１１中の
Poly−Si１７と薄いTi１４膜を介して接触して
いる。Poly−Si１８はソース３用電極としての
Poly−Si１０と参照電極５の電極としてのPoly
−Si１７とが一体化されたもので、これにより参
照電極５とFETのソース３が電気的に接続され
ている。素子の外部電極としてPoly−Si９のド
レイン電極の上部にAl電極６を形成した。同様
に参照電極５とソース３の共通電極１８の上部に
Al電極７を形成した。この事により従来必要と
したFET化学センサーのドレイン電極とソース
電極及び参照電極の３個を２個にする事が出来
た。 A first example will be described. FIG. 1 shows a plan view of a FET sensor for pH measurement, in which a reference electrode 5 and a FET chemical sensor are formed on a Si substrate 1. FIG. 2 shows a sectional view taken along line AA in FIG. 1, and FIG. 3 shows a sectional view taken along line BB. The FET chemical sensor itself has the structure of a conventional FET chemical sensor.
Using p-type Si as the substrate 1, drain 2 and source 3
This is an n-channel depletion type FET in which an n + diffusion layer is formed in the channel portion and an n-type surface layer 8 is formed in the channel portion. Gate 4 contains SiO 2 11, Si 3 N 4
12 films are formed on top of which an ion-sensitive film is formed.
Ta 2 O 5 13 is formed. On the other hand, the reference electrode 5
It consists of Ag15 and AgCl16, and is composed of SiO 2 11.
It is in contact with Poly-Si 17 through a thin Ti 14 film. Poly-Si18 is used as an electrode for source 3.
Poly-Si10 and Poly as reference electrode 5
-Si 17 is integrated, thereby electrically connecting the reference electrode 5 and the source 3 of the FET. An Al electrode 6 was formed on the drain electrode of Poly-Si 9 as an external electrode of the device. Similarly, on the top of the reference electrode 5 and the common electrode 18 of the source 3
An Al electrode 7 was formed. This made it possible to reduce the conventionally required three elements of the drain electrode, source electrode, and reference electrode of the FET chemical sensor to two.
次にこの素子の動作原理を述べる。この素子を
溶液につけると、H+イオンの濃度により、ゲー
ト４膜で発生している界面電位が発生する。ここ
で参照電極５によつて溶液に基準電位が与えられ
るが、参照電極５とFETのソース３が電気的に
接続されているので、両者の電位は等電位になつ
ている。この事によりH+イオンの濃度変化によ
るゲート電圧VGの変化は、ゲート−ソース間電
位VGSの変化となる。この変化がドレイン−ソー
ス間電流IDSの変化になつて現われる。この変化
を測定する事により溶液中のH+イオン濃度つま
りpHを測定出来る。第４図は第一の実施例によ
つてpH応答を調べたものでpH変化に対するドレ
イン−ソース電流IDS変化をゲート−ソース電位
VGS変化に変換しなおしてプロツトしたもので
54mV／pHの感度が得られた。 Next, the operating principle of this device will be described. When this element is immersed in a solution, an interfacial potential is generated in the gate 4 film due to the concentration of H + ions. Here, a reference potential is applied to the solution by the reference electrode 5, and since the reference electrode 5 and the source 3 of the FET are electrically connected, their potentials are equal. As a result, a change in the gate voltage V G due to a change in the concentration of H + ions becomes a change in the gate-source potential V GS . This change appears as a change in the drain-source current IDS . By measuring this change, the H + ion concentration, or pH, in the solution can be measured. Figure 4 shows the pH response investigated using the first example.
This is converted back to V GS change and plotted.
A sensitivity of 54 mV/pH was obtained.
第５図に第二の実施例を示す。FET化学セン
サーの動作は第一の実施例と同じであるが、ソー
ス３の上部に参照電極５をとりつけてあることが
特徴である。第６図に第５図のＣ−Ｃの断面図を
示す。ソース３電極としてのPoly−Si１０上部
のSiO2１１，Si3N4１２，Ta2O5１３膜をエツチ
ングしてホールを作りPoly−Si１０に薄いTi１
４膜を形成した後、参照電極５としてAg１５，
AgCl１６を形成する。この構造により参照電極
５とFET化学センサーのソース３電位を同じに
出来、かつ参照電極の面積を必要としないため素
子面積を大幅に削減出来た。 FIG. 5 shows a second embodiment. The operation of the FET chemical sensor is the same as in the first embodiment, but the feature is that a reference electrode 5 is attached above the source 3. FIG. 6 shows a sectional view taken along line CC in FIG. 5. The SiO 2 11, Si 3 N 4 12, and Ta 2 O 5 13 films on the top of the Poly-Si 10 as the source 3 electrode are etched to form holes and a thin Ti 1 layer is added to the Poly-Si 10.
After forming 4 films, Ag15,
Forms AgCl16. With this structure, the potential of the reference electrode 5 and the source 3 of the FET chemical sensor can be made the same, and since the area of the reference electrode is not required, the device area can be significantly reduced.
第７図に第三の実施例を示す。第三の実施例
は、炭酸ガスFETセンサーで第二の実施例のpH
測定用FETセンサーの上部にガス透過膜１９で
内部ゲル２０を挾みこんだ構造をとつている。動
作原理は、この素子を溶液につけたとき、溶液中
の炭酸ガスがガス透過膜１９を透過して内部ゲル
２０に溶けこむので、内部ゲル２０のpHが変化
する。このpH変化を下部のpHFETセンサーに
よつてとらえる。この事により溶液中の炭酸ガス
濃度を測定出来る。このように、参照電極と
FET化学センサーを一体化した構造をとる事に
より、膜で内部ゲルを挾みこむ炭酸ガスセンサー
における素子の小型化を可能にする事が出来る。 FIG. 7 shows a third embodiment. The third embodiment uses a carbon dioxide FET sensor to detect the pH of the second embodiment.
It has a structure in which an internal gel 20 is sandwiched between a gas permeable membrane 19 and a gas permeable membrane 19 above the measurement FET sensor. The operating principle is that when this element is immersed in a solution, carbon dioxide gas in the solution passes through the gas permeable membrane 19 and dissolves into the internal gel 20, so that the pH of the internal gel 20 changes. This pH change is detected by the pHFET sensor at the bottom. This allows the concentration of carbon dioxide in the solution to be measured. In this way, the reference electrode and
By adopting a structure that integrates the FET chemical sensor, it is possible to miniaturize the element in a carbon dioxide gas sensor that sandwiches an internal gel with a membrane.
また第一、第二実施例のゲート膜上にさらに酵
素固定膜をつける事により、酵素センサーとして
作動した。 Further, by further attaching an enzyme-immobilized membrane on the gate membrane of the first and second embodiments, it operated as an enzyme sensor.
上述した本発明の各実施例によれば、参照電極
とFETを基板上で一体化する事により、化学セ
ンサー素子の面積を小さく出来た。この事により
局所的なイオン濃度を測定出来るため試料の量を
少なく出来る。また生体から発生する電気的ノイ
ズを低減出来るため、生体モニターとしての植め
込み型センサーが可能となる。更に、参照電極の
リード線が不用となり、外部計測回路が極めて簡
単になる。 According to each of the embodiments of the present invention described above, the area of the chemical sensor element can be reduced by integrating the reference electrode and the FET on the substrate. This makes it possible to measure local ion concentrations, which allows the amount of sample to be reduced. Furthermore, since electrical noise generated from living organisms can be reduced, it becomes possible to use implantable sensors as biological monitors. Furthermore, a lead wire for the reference electrode is no longer required, and the external measurement circuit becomes extremely simple.
一体化に伴う具体的な効果を述べる。参照電極
とセンサーのソース部を接続する事によりセンサ
ーのリード線の本数を３本から２本にする事が出
来た。 Describe the specific effects of integration. By connecting the reference electrode and the sensor source, we were able to reduce the number of sensor lead wires from three to two.
さらにセンサーのソース部に直接参照電極をつ
ける事により、参照電極面積をSR、FET化学セ
ンサーの面積をSFとすると一体化した素子面積
は、従来素子面積で必要であつたSR＋SFがSFだけ
ですむようになつた。 Furthermore, by attaching a reference electrode directly to the source part of the sensor, if the reference electrode area is S R and the area of the FET chemical sensor is S F , the integrated element area is S R + S F , which was required for the conventional element area. But now I only need SF .
本発明によれば、参照電極のリード線を無くす
ることができるので、化学センサーに対する外部
からの電気的ノイズを低減でき、かつ溶液中の被
検物質濃度を極めて簡素化された構成の化学セン
サーで測定することが可能となる。
According to the present invention, since the lead wire of the reference electrode can be eliminated, it is possible to reduce electrical noise from the outside to the chemical sensor, and the chemical sensor has an extremely simplified configuration that can reduce the concentration of the analyte in the solution. It becomes possible to measure by
第１図は本発明の一実施例の参照電極とFET
化学センサーを一体化した素子の平面図、第２図
は第１図のＡ−Ａ線断面図、第３図は第１図のＢ
−Ｂ線断面図、第４図は第一の実施例のセンサー
のpH応答を示す特性図、第５図は本発明の他の
実施例の参照電極をFETのソース部分の上部に
取り付けた素子の平面図、第６図は第５図のＣ−
Ｃ線断面図、第７図は本発明のさらに他の実施例
の酵素固定膜をゲート膜上にとりつけた素子の断
面図である。
１……Si基板、２……ドレイン、３……ソー
ス、４……ゲート、５……参照電極（Ag／
AgCl）、６ドレイン用Al電極、７……ソース用
Al電極、８……ｎ型表面層、９……ドレイン用
Poly−Si電極、１０……ソース用Poly−Si電極、
１１……SiO2、１２……Si3N4、１３……Ta2
O5、１４……Ti、１５……Ag、１６……AgCl、
１７……参照電極用電極Poly−Si、１８……
Poly−Si、１９……ガス透過膜、２０……内部
ゲル。
Figure 1 shows the reference electrode and FET of one embodiment of the present invention.
A plan view of an element that integrates a chemical sensor, Figure 2 is a sectional view taken along line A-A in Figure 1, and Figure 3 is a cross-sectional view taken along line B in Figure 1.
-B cross-sectional view, Figure 4 is a characteristic diagram showing the pH response of the sensor of the first embodiment, and Figure 5 is an element in which a reference electrode of another embodiment of the present invention is attached above the source part of the FET. The plan view of Fig. 6 is C- of Fig. 5.
A cross-sectional view taken along the line C and FIG. 7 are cross-sectional views of a device in which an enzyme-immobilized membrane according to still another embodiment of the present invention is attached on a gate membrane. 1...Si substrate, 2...Drain, 3...Source, 4...Gate, 5...Reference electrode (Ag/
AgCl), 6 Al electrode for drain, 7... for source
Al electrode, 8... n-type surface layer, 9... for drain
Poly-Si electrode, 10...Poly-Si electrode for source,
11...SiO 2 , 12...Si 3 N 4 , 13...Ta 2
O 5 , 14...Ti, 15...Ag, 16...AgCl,
17... Reference electrode Poly-Si, 18...
Poly-Si, 19... Gas permeable membrane, 20... Internal gel.
Claims (1)
およびドレイン用電極を設け、上記SiO2層上に
イオン感応膜を設けたFET化学センサーにおい
て、上記SiO2層上に参照電極を形成し、上記ソ
ース用電極と上記参照電極とを、上記SiO2層内
において電気的に接続したことを特徴とする
FET化学センサー。 ２ 上記参照電極は、導電性材料を介して上記ソ
ース用電極の上部に配置されていることを特徴と
する特許請求の範囲第１項記載のFET化学セン
サー。[Claims] 1. In an FET chemical sensor in which a source electrode and a drain electrode are provided in a SiO 2 layer on a silicon substrate, and an ion-sensitive film is provided on the SiO 2 layer, a reference is made on the SiO 2 layer. An electrode is formed, and the source electrode and the reference electrode are electrically connected within the SiO 2 layer.
FET chemical sensor. 2. The FET chemical sensor according to claim 1, wherein the reference electrode is placed above the source electrode via a conductive material.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58080887A JPS59206756A (en) | 1983-05-11 | 1983-05-11 | Fet chemical sensor combined with reference electrode |
| DE19843417137 DE3417137C2 (en) | 1983-05-11 | 1984-05-09 | Chemically sensitive field effect transistor measuring device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58080887A JPS59206756A (en) | 1983-05-11 | 1983-05-11 | Fet chemical sensor combined with reference electrode |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS59206756A JPS59206756A (en) | 1984-11-22 |
| JPH0469338B2 true JPH0469338B2 (en) | 1992-11-05 |
Family
ID=13730852
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP58080887A Granted JPS59206756A (en) | 1983-05-11 | 1983-05-11 | Fet chemical sensor combined with reference electrode |
Country Status (2)
| Country | Link |
|---|---|
| JP (1) | JPS59206756A (en) |
| DE (1) | DE3417137C2 (en) |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3519397A1 (en) * | 1985-05-30 | 1986-12-04 | Siemens AG, 1000 Berlin und 8000 München | Sensor for gas analysis and detection |
| JPS6283641A (en) * | 1985-10-08 | 1987-04-17 | Sharp Corp | Sensor element |
| JPH0725688Y2 (en) * | 1985-12-18 | 1995-06-07 | 新電元工業株式会社 | Semiconductor ion sensor |
| FR2672158B1 (en) * | 1991-01-24 | 1993-04-09 | Commissariat Energie Atomique | SENSOR FOR THE DETECTION OF CHEMICAL SPECIES OR PHOTONS USING A FIELD EFFECT TRANSISTOR. |
| US20110100810A1 (en) * | 2008-06-30 | 2011-05-05 | Nxp B.V. | Chip integrated ion sensor |
| JP5527139B2 (en) * | 2010-09-28 | 2014-06-18 | 大日本印刷株式会社 | Measuring method using biosensor and biosensor |
| TWI432724B (en) | 2010-10-18 | 2014-04-01 | Ind Tech Res Inst | Microsystem for analyzing blood |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5672339A (en) * | 1979-11-16 | 1981-06-16 | Kuraray Co Ltd | Fet multisensor |
-
1983
- 1983-05-11 JP JP58080887A patent/JPS59206756A/en active Granted
-
1984
- 1984-05-09 DE DE19843417137 patent/DE3417137C2/en not_active Expired
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5672339A (en) * | 1979-11-16 | 1981-06-16 | Kuraray Co Ltd | Fet multisensor |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS59206756A (en) | 1984-11-22 |
| DE3417137C2 (en) | 1987-03-26 |
| DE3417137A1 (en) | 1984-11-15 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4508613A (en) | Miniaturized potassium ion sensor | |
| US4218298A (en) | Selective chemical sensitive FET transducer | |
| US4739380A (en) | Integrated ambient sensing devices and methods of manufacture | |
| US5384028A (en) | Biosensor with a data memory | |
| Poghossian et al. | Detecting both physical and (bio‐) chemical parameters by means of ISFET devices | |
| US7435610B2 (en) | Fabrication of array pH sensitive EGFET and its readout circuit | |
| US20040079636A1 (en) | Biomedical ion sensitive semiconductor sensor and sensor array | |
| Tsukada et al. | An integrated chemical sensor with multiple ion and gas sensors | |
| US5078855A (en) | Chemical sensors and their divided parts | |
| US5387328A (en) | Bio-sensor using ion sensitive field effect transistor with platinum electrode | |
| Seo et al. | ISFET glucose sensor based on a new principle using the electrolysis of hydrogen peroxide | |
| US20070000778A1 (en) | Multi-parameter sensor with readout circuit | |
| Poghossian | Method of fabrication of ISFET-based biosensors on an Si–SiO2–Si structure | |
| US10739305B1 (en) | Biosensing systems and methods using a FET | |
| JPH0469338B2 (en) | ||
| KR101901193B1 (en) | Biosensor | |
| JP2514280B2 (en) | Integrated ion sensor | |
| JP3167022B2 (en) | Gas sensor | |
| US8410530B2 (en) | Sensitive field effect transistor apparatus | |
| Alcacer et al. | eHealth system with ISFET-based immunosensor for heart failure biomarker detection in saliva | |
| JPS6073351A (en) | Element for fet chemical sensor | |
| Van den Vlekkert | Ion-sensitive field effect transistors | |
| JPH0422293Y2 (en) | ||
| Harame | INTEGRATED CIRCUIT CHEMICAL SENSORS. | |
| JPS62110145A (en) | Environment detector and manufacture thereof |