JPS63298148A - Thin film type ozone sensor - Google Patents
Thin film type ozone sensorInfo
- Publication number
- JPS63298148A JPS63298148A JP62135609A JP13560987A JPS63298148A JP S63298148 A JPS63298148 A JP S63298148A JP 62135609 A JP62135609 A JP 62135609A JP 13560987 A JP13560987 A JP 13560987A JP S63298148 A JPS63298148 A JP S63298148A
- Authority
- JP
- Japan
- Prior art keywords
- thin film
- ozone
- sensor
- film layer
- 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
Links
- 239000010409 thin film Substances 0.000 title claims abstract description 59
- CBENFWSGALASAD-UHFFFAOYSA-N Ozone Chemical compound [O-][O+]=O CBENFWSGALASAD-UHFFFAOYSA-N 0.000 title claims abstract description 54
- 239000004065 semiconductor Substances 0.000 claims abstract description 32
- 239000000758 substrate Substances 0.000 claims abstract description 20
- 239000010408 film Substances 0.000 claims description 13
- 239000010410 layer Substances 0.000 abstract description 31
- 230000035945 sensitivity Effects 0.000 abstract description 9
- PJXISJQVUVHSOJ-UHFFFAOYSA-N indium(III) oxide Inorganic materials [O-2].[O-2].[O-2].[In+3].[In+3] PJXISJQVUVHSOJ-UHFFFAOYSA-N 0.000 abstract description 5
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 abstract description 2
- 239000002344 surface layer Substances 0.000 abstract description 2
- 238000001771 vacuum deposition Methods 0.000 abstract 1
- 239000007789 gas Substances 0.000 description 8
- 238000000034 method Methods 0.000 description 5
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 4
- 238000010586 diagram Methods 0.000 description 4
- 229910052814 silicon oxide Inorganic materials 0.000 description 4
- 230000007423 decrease Effects 0.000 description 3
- 230000007774 longterm Effects 0.000 description 3
- 230000001590 oxidative effect Effects 0.000 description 3
- 230000000694 effects Effects 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 238000004847 absorption spectroscopy Methods 0.000 description 1
- 238000005229 chemical vapour deposition Methods 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 238000004332 deodorization Methods 0.000 description 1
- 238000002848 electrochemical method Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 229910044991 metal oxide Inorganic materials 0.000 description 1
- 150000004706 metal oxides Chemical class 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 238000005240 physical vapour deposition Methods 0.000 description 1
- 238000000197 pyrolysis Methods 0.000 description 1
- 238000002798 spectrophotometry method Methods 0.000 description 1
- 230000001954 sterilising effect Effects 0.000 description 1
- 238000004659 sterilization and disinfection Methods 0.000 description 1
- 238000004448 titration Methods 0.000 description 1
- 231100000331 toxic Toxicity 0.000 description 1
- 230000002588 toxic effect Effects 0.000 description 1
- 238000007738 vacuum evaporation Methods 0.000 description 1
- 238000004065 wastewater treatment Methods 0.000 description 1
Landscapes
- Investigating Or Analyzing Materials By The Use Of Fluid Adsorption Or Reactions (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は、低濃度オゾンに対して高感度な薄膜型オゾン
センサに関する。 。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a thin film ozone sensor that is highly sensitive to low concentration ozone. .
オゾンはその強力な酸化力のため、殺菌、脱臭、酸化等
の目的で医療用、食品工業、排水処理、半導体製造プロ
セスなど多方面に亘って使用され、その使用量も増大の
一途をたどっている。しかし、オゾンは酸化力が強いた
め、人体への毒性が強く、その許容濃度はＯ，ｌｐｐｍ
と規定されており、従って、従来より取り扱いが簡便で
信頼性が高く、しかも安価な高感度センサの開発が望ま
れている。Due to its strong oxidizing power, ozone is used for purposes such as sterilization, deodorization, and oxidation in a wide variety of fields, including medical, food industry, wastewater treatment, and semiconductor manufacturing processes, and the amount used continues to increase. There is. However, due to its strong oxidizing power, ozone is highly toxic to the human body, and its permissible concentration is O,lppm.
Therefore, it is desired to develop a high-sensitivity sensor that is easier to handle, more reliable, and less expensive than conventional sensors.
従来、低濃度のオゾンの測定方法としては、酸化還元滴
定法、吸光光度法、電気化学的方法や紫外線吸収スペク
Ｉ・ル法などが提案されているが、それらは一般に大型
の測定装置を必要として高価であるとともに、取り扱い
が複雑であるなどの欠点を有している。Conventionally, methods for measuring low concentrations of ozone have been proposed, such as redox titration, spectrophotometry, electrochemical methods, and ultraviolet absorption spectrometry, but these generally require large measuring equipment. It has drawbacks such as being expensive and complicated to handle.
（発明が解決しようとする問題点〕
一方、従来より安価であり、また取り扱いが容易なガス
センザとして、焼結型もしくは厚膜型と呼ばれている半
導体ガスセンサが提供されている。ところが、上記半導
体ガスセンサはオゾンに対してほとんど感応せず、オゾ
ンセンサとして使用されていないのが実情である。すな
わち、オゾンは極めて酸化力が強く、自然に分解する性
質を有しているために、上記半導体ガスセンサではセン
サ内部に到達するまでにセンサ表層で反応分解してしま
い、該センサの感度に寄与しないものであった。(Problems to be Solved by the Invention) On the other hand, semiconductor gas sensors called sintered type or thick film type have been provided as gas sensors that are cheaper and easier to handle than conventional ones. The reality is that gas sensors are hardly sensitive to ozone and are not used as ozone sensors.In other words, ozone has extremely strong oxidizing power and has the property of decomposing naturally, so the semiconductor gas sensor described above is However, before it reaches the inside of the sensor, it reacts and decomposes on the surface of the sensor, and does not contribute to the sensitivity of the sensor.
本発明は上記の実情に着目してなされたものであって、
低濃度オゾンに対して信頼性が高く、高感度であり、し
かも取り扱いが簡便で、且つ安価な薄膜型オゾンセンサ
を提供することを目的とする。The present invention has been made focusing on the above-mentioned circumstances, and
It is an object of the present invention to provide a thin film ozone sensor that is highly reliable and sensitive to low concentration ozone, easy to handle, and inexpensive.
すなわち、本発明に係る薄膜型オゾンセンサの特徴構成
は、基板にＩｎｚ（Ｌ＋を主成分とする半導体薄膜層を
形成してある薄膜型オゾンセンサであって、基板に膜厚
が１μｍ以下のＩｎ２０３を主成分とする半導体薄膜層
を形成してある点にあり、その作用及び効果は次の通り
である。That is, the characteristic configuration of the thin film type ozone sensor according to the present invention is that it is a thin film type ozone sensor in which a semiconductor thin film layer containing Inz (L+ as a main component) is formed on a substrate, and the substrate has an In203 layer with a film thickness of 1 μm or less. The main component of the semiconductor thin film layer is formed, and its functions and effects are as follows.
基板に半導体薄膜層を形成した薄膜型センサを用いてい
るので、従来の焼結型もしくは厚膜型と呼ばれている半
導体ガスセンサのように、オゾンが該センサの表層で反
応分解することがなく、オゾンがセンサの感知部にまで
到達できて感知部で反応することになるから、オゾンセ
ンサとして機能することができる。しかも、その半導体
薄膜層としては、膜厚が１μｍ以下のＩｎ２Ｏ３を主成
分としたもので形成したので、信頼性が高く、高感度に
オゾンを測定することができる。つまり、種々の半導体
薄膜や種々の膜厚の薄膜について試作検討した結果、後
述するように膜厚１μｍ以下のＩｎｚ０３系薄膜型セン
サが、例えば１ ｐｐｍ以下の低濃度オゾンに対しても
高感度であり、しかもセンサとしての各特性に優れてい
ることが見出されたのである。Because it uses a thin film sensor with a semiconductor thin film layer formed on the substrate, ozone does not react and decompose on the surface layer of the sensor, unlike conventional sintered or thick film semiconductor gas sensors. Since ozone can reach the sensing part of the sensor and react there, it can function as an ozone sensor. Moreover, since the semiconductor thin film layer is formed of a film mainly composed of In2O3 and has a thickness of 1 μm or less, ozone can be measured with high reliability and high sensitivity. In other words, as a result of prototyping and investigating various semiconductor thin films and thin films with various thicknesses, we found that an Inz03 thin film sensor with a film thickness of 1 μm or less has high sensitivity even to low concentrations of ozone, for example, 1 ppm or less. Moreover, it was discovered that it has excellent characteristics as a sensor.
その結果、低濃度のオゾンに対して信頼性が高く、高感
度であるとともに、取り扱いが簡便であり、且つ安価な
薄膜型オゾンセンサを提供できるようになった。As a result, it has become possible to provide a thin-film ozone sensor that is highly reliable and sensitive to low-concentration ozone, is easy to handle, and is inexpensive.
以下、本発明の実施例を詳細に説明する。 Examples of the present invention will be described in detail below.
第１図及び第２図には薄膜型オゾンセンサの概略斜視図
と概略断面図が示されており、図に示すように該センサ
はアルミナなどの絶縁性基板（１）の表面にＩｎｚＯａ
を主成分とする半導体の薄膜層（２）を形成して構成さ
れたものである。前記基板（１）は加熱機能と抵抗値変
化を測定できる機能を備えたものであれば、いずれのも
のでも使用することができ限定するものではない。1 and 2 show a schematic perspective view and a schematic cross-sectional view of a thin film ozone sensor.
It is constructed by forming a thin film layer (2) of a semiconductor whose main component is The substrate (1) may be any substrate as long as it has a heating function and a function of measuring resistance change, and is not limited to any one.
また、前記薄膜層（２）は熱分解法、化学蒸着法、物理
蒸着法その他の膜作製法によって基板（１）の表面に形
成することができる。この半導体薄膜層（２）の膜厚は
１μｍ以下であり、該膜厚が１μｍを超える場合には、
例えば１ ｐｐｍ程度の低濃度のオゾンに対してセンサ
出力が低く、実用的でないものである。また、センサの
安定性を確保する上で、半導体薄膜層（２）の膜厚は３
００Å〜１μｍとするのが好ましく、更に３００Å〜５
０００人とするのが好ましい。すなわち、半導体薄膜層
（２）の膜厚が３００人未満の場合には、オゾンに対し
て高感度であるが、経時変化が大きく長期安定性に劣る
欠点があるからである。尚、図中（３）は基板（１）の
表面に形成された櫛型電極、（２）はその電極（３）を
覆うように基板（１）上に形成された半導体薄膜層、（
４）は絶縁基板（１）裏面に付着されたヒータであり、
第１図に示すように、前記電極（３）は半導体薄膜層（
２）を透過して表面側から見えている。Further, the thin film layer (2) can be formed on the surface of the substrate (1) by a pyrolysis method, a chemical vapor deposition method, a physical vapor deposition method, or other film forming method. The film thickness of this semiconductor thin film layer (2) is 1 μm or less, and when the film thickness exceeds 1 μm,
For example, the sensor output is low for ozone at a low concentration of about 1 ppm, making it impractical. In addition, in order to ensure the stability of the sensor, the thickness of the semiconductor thin film layer (2) is 3.
The thickness is preferably 00 Å to 1 μm, and more preferably 300 Å to 5 μm.
000 people is preferable. That is, when the thickness of the semiconductor thin film layer (2) is less than 300 layers, it is highly sensitive to ozone, but has the drawback of large changes over time and poor long-term stability. In the figure, (3) is a comb-shaped electrode formed on the surface of the substrate (1), (2) is a semiconductor thin film layer formed on the substrate (1) so as to cover the electrode (3), and (
4) is a heater attached to the back surface of the insulating substrate (1),
As shown in FIG. 1, the electrode (3) is a semiconductor thin film layer (
2) and is visible from the surface side.
次に、本発明を具体的に説明する。Next, the present invention will be specifically explained.
第１図及び第２図で示したように、アルミナ基板（１）
上に形成された電極（３）を覆うようにこの基板（１）
上にＩｎ２０１を主成分とする半導体薄膜層（２）を真
空蒸着法により形成して、薄膜型オゾンセンサを作成し
た。次に、上記構成の薄膜型オゾンセンサにおける、オ
ゾン感度の膜厚依存性を測定した。結果を第３図に示す
。この図より、半導体薄膜層の膜厚が厚くなるにつれて
、オゾン感度が低下する傾向にあることが分かり、殊に
膜厚が１μｍを超える場合には低濃度オゾンの感度が大
きく低下していることが確認された。As shown in Figures 1 and 2, the alumina substrate (1)
This substrate (1) covers the electrode (3) formed on it.
A semiconductor thin film layer (2) containing In201 as a main component was formed thereon by vacuum evaporation to create a thin film ozone sensor. Next, the film thickness dependence of ozone sensitivity in the thin film ozone sensor having the above configuration was measured. The results are shown in Figure 3. From this figure, it can be seen that as the thickness of the semiconductor thin film layer increases, the ozone sensitivity tends to decrease, and especially when the thickness exceeds 1 μm, the sensitivity to low concentration ozone decreases significantly. was confirmed.
また、第４図には半導体薄膜層の膜厚を変えた場合の、
０．５ｐｐｍオゾン濃度に対する規格化された出力の経
時変化が示されている。この図より、膜厚が薄くなるに
つれて経時変化が大きく、長期安定性に劣っていること
が分かる。また、第５図には半導体薄膜層の膜厚が３０
０人の薄膜型オゾンセンサを用いた、０．５ｐｐｍオゾ
ン濃度に対する応答波形と再現性が示されている。この
図より、応答速度及び再現性とも優れていることが確認
された。In addition, Fig. 4 shows the results when the thickness of the semiconductor thin film layer is changed.
The normalized power over time is shown for a 0.5 ppm ozone concentration. From this figure, it can be seen that as the film thickness becomes thinner, the change over time becomes larger and the long-term stability is inferior. In addition, in FIG. 5, the thickness of the semiconductor thin film layer is 30 mm.
The response waveform and reproducibility for an ozone concentration of 0.5 ppm using a thin film ozone sensor for 0 persons are shown. From this figure, it was confirmed that both response speed and reproducibility were excellent.
第６図に示すように、基板（１）の同一表面上に櫛型電
極（３）とヒータ（４）をそれぞれ形成し、この電極（
３）を覆うように基板（１）上に前記半導体薄膜層（２
）を形成しても良く、また第７図に示すように、基板（
１）表面にヒータ（４）を兼ねた電極（３）を形成し、
これを覆うように基板（１）表面に半導体薄膜層（２）
を形成しても良い。さらに、ヒータ（４）を基板（１）
内部に埋設してもよいものである。As shown in FIG. 6, a comb-shaped electrode (3) and a heater (4) are formed on the same surface of the substrate (1), and the electrode (
3) on the substrate (1) so as to cover the semiconductor thin film layer (2).
), or as shown in FIG.
1) Form an electrode (3) that also serves as a heater (4) on the surface,
A semiconductor thin film layer (2) is placed on the surface of the substrate (1) to cover this.
may be formed. Furthermore, the heater (4) is attached to the substrate (1).
It may be buried inside.
尚、前記半導体薄膜層（２）の表面に珪素酸化物の薄膜
層を形成して、薄膜型オゾンセンサを構成したり、又は
前記半導体薄膜層（２）の表面に金属酸化物の薄層を形
成し、その表面に珪素酸化物の薄膜層を被覆しても良い
。このようにすれば、還元性ガスに対する選択性に優れ
たオゾンセンサとして使用することができる。すなわち
、還元性ガスが共存する場合には、オゾン出力が低下し
、正確なオゾン濃度を測定できない場合があるが、この
Ｉｎ２Ｏ３の半導体薄膜層の表面を珪素酸化物の薄膜層
で被覆することにより、オゾンガスに対する選択性を高
めることができるのである。A thin film type ozone sensor may be constructed by forming a thin film layer of silicon oxide on the surface of the semiconductor thin film layer (2), or a thin film layer of metal oxide may be formed on the surface of the semiconductor thin film layer (2). The surface of the silicon oxide layer may be coated with a thin film layer of silicon oxide. In this way, it can be used as an ozone sensor with excellent selectivity for reducing gases. In other words, when a reducing gas coexists, the ozone output decreases and accurate ozone concentration measurement may not be possible. However, by coating the surface of this In2O3 semiconductor thin film layer with a silicon oxide thin film layer, , the selectivity to ozone gas can be increased.
又、特許請求の範囲の項に図面との対照を便利にする為
に符号を記すが、該記入により本発明は添付図面の構造
に限定されるものではない。Further, although reference numerals are written in the claims section for convenient comparison with the drawings, the present invention is not limited to the structure shown in the accompanying drawings by the reference numerals.
図面は本発明に係る薄膜型オゾンセンサの実施例を示し
、第１図は薄膜型オゾンセンサの斜視図、第２図はその
断面図、第３図はオゾン感度の膜厚依存性を示す図、第
４図は薄膜型オゾンセンサの半導体薄膜層の膜厚を変え
た場合の長期安定性を示す図、第５図は薄膜型オゾンセ
ンサのオゾンに対する応答波形と再現性を示す図、第６
図及び第７図はそれぞれ薄膜型オゾンセンサの概略平面
図である。
（１）・・・・・・基板、（２）・・・・・・半導体薄
膜層。The drawings show an embodiment of the thin film ozone sensor according to the present invention, in which Fig. 1 is a perspective view of the thin film ozone sensor, Fig. 2 is a sectional view thereof, and Fig. 3 is a diagram showing the dependence of ozone sensitivity on film thickness. , Fig. 4 is a diagram showing the long-term stability when the film thickness of the semiconductor thin film layer of the thin-film ozone sensor is changed, Fig. 5 is a diagram showing the response waveform and reproducibility of the thin-film ozone sensor to ozone, and Fig. 6 is a diagram showing the response waveform and reproducibility of the thin-film ozone sensor to ozone.
7 and 7 are schematic plan views of a thin film ozone sensor, respectively. (1)...Substrate, (2)...Semiconductor thin film layer.
Claims (1)
薄膜層（２）を形成してある薄膜型オゾンセンサであっ
て、前記半導体薄膜層（２）の膜厚を１μｍ以下に設定
してある薄膜型オゾンセンサ。 ２、前記半導体薄膜層（２）の膜厚が３００Å〜１μｍ
である特許請求の範囲第１項に記載の薄膜型オゾンセン
サ。 ３、前記半導体薄膜層（２）の膜厚が３００Å〜５００
０Åである特許請求の範囲第１項に記載の薄膜型オゾン
センサ。[Claims] 1. A thin film ozone sensor in which a semiconductor thin film layer (2) mainly composed of In_2O_3 is formed on a substrate (1), the film thickness of the semiconductor thin film layer (2) being 1 μm. Thin film ozone sensor set below. 2. The thickness of the semiconductor thin film layer (2) is 300 Å to 1 μm.
A thin film ozone sensor according to claim 1. 3. The thickness of the semiconductor thin film layer (2) is 300 Å to 500 Å.
The thin film ozone sensor according to claim 1, which has a thickness of 0 Å.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62135609A JPH0668475B2 (en) | 1987-05-29 | 1987-05-29 | Thin film ozone sensor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62135609A JPH0668475B2 (en) | 1987-05-29 | 1987-05-29 | Thin film ozone sensor |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS63298148A true JPS63298148A (en) | 1988-12-05 |
| JPH0668475B2 JPH0668475B2 (en) | 1994-08-31 |
Family
ID=15155815
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP62135609A Expired - Lifetime JPH0668475B2 (en) | 1987-05-29 | 1987-05-29 | Thin film ozone sensor |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0668475B2 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH02240537A (en) * | 1989-03-14 | 1990-09-25 | Fuji Electric Co Ltd | Analysis apparatus for ozone in solution |
| JPH02240538A (en) * | 1989-03-14 | 1990-09-25 | Fuji Electric Co Ltd | Analysis apparatus for ozone in solution |
| JPH02263146A (en) * | 1989-04-04 | 1990-10-25 | Mitsubishi Electric Corp | Ozone sensor |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3778229A (en) * | 1972-03-29 | 1973-12-11 | Gen Electric | Ozone gas detector |
| JPS549996A (en) * | 1977-06-24 | 1979-01-25 | Figaro Eng | Improvement for gas sensitivity of gas detecting element |
| JPS549994A (en) * | 1977-06-24 | 1979-01-25 | Figaro Eng | Gas detecting element |
-
1987
- 1987-05-29 JP JP62135609A patent/JPH0668475B2/en not_active Expired - Lifetime
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3778229A (en) * | 1972-03-29 | 1973-12-11 | Gen Electric | Ozone gas detector |
| JPS549996A (en) * | 1977-06-24 | 1979-01-25 | Figaro Eng | Improvement for gas sensitivity of gas detecting element |
| JPS549994A (en) * | 1977-06-24 | 1979-01-25 | Figaro Eng | Gas detecting element |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH02240537A (en) * | 1989-03-14 | 1990-09-25 | Fuji Electric Co Ltd | Analysis apparatus for ozone in solution |
| JPH02240538A (en) * | 1989-03-14 | 1990-09-25 | Fuji Electric Co Ltd | Analysis apparatus for ozone in solution |
| JPH02263146A (en) * | 1989-04-04 | 1990-10-25 | Mitsubishi Electric Corp | Ozone sensor |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0668475B2 (en) | 1994-08-31 |
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