DE102013207310A1 - gas sensor - Google Patents
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- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 claims abstract description 48
- 229910002092 carbon dioxide Inorganic materials 0.000 claims abstract description 24
- 239000001569 carbon dioxide Substances 0.000 claims abstract description 24
- XLOMVQKBTHCTTD-UHFFFAOYSA-N Zinc monoxide Chemical compound [Zn]=O XLOMVQKBTHCTTD-UHFFFAOYSA-N 0.000 claims abstract description 16
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims abstract description 11
- 229910052782 aluminium Inorganic materials 0.000 claims abstract description 8
- 239000011787 zinc oxide Substances 0.000 claims abstract description 7
- 239000000203 mixture Substances 0.000 claims abstract description 6
- 230000005669 field effect Effects 0.000 claims description 17
- 239000000758 substrate Substances 0.000 claims description 10
- 238000004519 manufacturing process Methods 0.000 claims description 4
- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical compound O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 claims description 4
- 229910000611 Zinc aluminium Inorganic materials 0.000 claims description 3
- 239000011230 binding agent Substances 0.000 claims description 3
- 238000000137 annealing Methods 0.000 claims description 2
- 238000000151 deposition Methods 0.000 claims 1
- 239000007789 gas Substances 0.000 description 35
- 238000005259 measurement Methods 0.000 description 8
- 239000003570 air Substances 0.000 description 7
- 238000004378 air conditioning Methods 0.000 description 5
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 4
- WSFSSNUMVMOOMR-UHFFFAOYSA-N Formaldehyde Chemical compound O=C WSFSSNUMVMOOMR-UHFFFAOYSA-N 0.000 description 4
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- 238000000034 method Methods 0.000 description 4
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- CBENFWSGALASAD-UHFFFAOYSA-N Ozone Chemical compound [O-][O+]=O CBENFWSGALASAD-UHFFFAOYSA-N 0.000 description 3
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 description 3
- 238000010438 heat treatment Methods 0.000 description 3
- 230000003287 optical effect Effects 0.000 description 3
- 230000009257 reactivity Effects 0.000 description 3
- 239000004065 semiconductor Substances 0.000 description 3
- MGWGWNFMUOTEHG-UHFFFAOYSA-N 4-(3,5-dimethylphenyl)-1,3-thiazol-2-amine Chemical compound CC1=CC(C)=CC(C=2N=C(N)SC=2)=C1 MGWGWNFMUOTEHG-UHFFFAOYSA-N 0.000 description 2
- HGINCPLSRVDWNT-UHFFFAOYSA-N Acrolein Chemical compound C=CC=O HGINCPLSRVDWNT-UHFFFAOYSA-N 0.000 description 2
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- YNQLUTRBYVCPMQ-UHFFFAOYSA-N Ethylbenzene Chemical compound CCC1=CC=CC=C1 YNQLUTRBYVCPMQ-UHFFFAOYSA-N 0.000 description 2
- YGYAWVDWMABLBF-UHFFFAOYSA-N Phosgene Chemical compound ClC(Cl)=O YGYAWVDWMABLBF-UHFFFAOYSA-N 0.000 description 2
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 2
- PPBRXRYQALVLMV-UHFFFAOYSA-N Styrene Chemical compound C=CC1=CC=CC=C1 PPBRXRYQALVLMV-UHFFFAOYSA-N 0.000 description 2
- 239000004411 aluminium Substances 0.000 description 2
- 229910002091 carbon monoxide Inorganic materials 0.000 description 2
- 230000008859 change Effects 0.000 description 2
- MVPPADPHJFYWMZ-UHFFFAOYSA-N chlorobenzene Chemical compound ClC1=CC=CC=C1 MVPPADPHJFYWMZ-UHFFFAOYSA-N 0.000 description 2
- 230000001419 dependent effect Effects 0.000 description 2
- 230000006012 detection of carbon dioxide Effects 0.000 description 2
- 235000019256 formaldehyde Nutrition 0.000 description 2
- 229930195733 hydrocarbon Natural products 0.000 description 2
- 150000002430 hydrocarbons Chemical class 0.000 description 2
- 235000011167 hydrochloric acid Nutrition 0.000 description 2
- 230000002452 interceptive effect Effects 0.000 description 2
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 2
- JCXJVPUVTGWSNB-UHFFFAOYSA-N nitrogen dioxide Inorganic materials O=[N]=O JCXJVPUVTGWSNB-UHFFFAOYSA-N 0.000 description 2
- 239000001272 nitrous oxide Substances 0.000 description 2
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- 229910052710 silicon Inorganic materials 0.000 description 2
- 239000010703 silicon Substances 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- 238000004611 spectroscopical analysis Methods 0.000 description 2
- 229910052815 sulfur oxide Inorganic materials 0.000 description 2
- 239000012855 volatile organic compound Substances 0.000 description 2
- 125000002934 2-oxopropylidene group Chemical group 0.000 description 1
- 229910018072 Al 2 O 3 Inorganic materials 0.000 description 1
- OTMSDBZUPAUEDD-UHFFFAOYSA-N Ethane Chemical compound CC OTMSDBZUPAUEDD-UHFFFAOYSA-N 0.000 description 1
- VGGSQFUCUMXWEO-UHFFFAOYSA-N Ethene Chemical compound C=C VGGSQFUCUMXWEO-UHFFFAOYSA-N 0.000 description 1
- ZZSNKZQZMQGXPY-UHFFFAOYSA-N Ethyl cellulose Chemical compound CCOCC1OC(OC)C(OCC)C(OCC)C1OC1C(O)C(O)C(OC)C(CO)O1 ZZSNKZQZMQGXPY-UHFFFAOYSA-N 0.000 description 1
- 239000001856 Ethyl cellulose Substances 0.000 description 1
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical class Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
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- ISWSIDIOOBJBQZ-UHFFFAOYSA-N Phenol Chemical compound OC1=CC=CC=C1 ISWSIDIOOBJBQZ-UHFFFAOYSA-N 0.000 description 1
- UCKMPCXJQFINFW-UHFFFAOYSA-N Sulphide Chemical compound [S-2] UCKMPCXJQFINFW-UHFFFAOYSA-N 0.000 description 1
- HSFWRNGVRCDJHI-UHFFFAOYSA-N alpha-acetylene Natural products C#C HSFWRNGVRCDJHI-UHFFFAOYSA-N 0.000 description 1
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 1
- 239000012080 ambient air Substances 0.000 description 1
- 150000001408 amides Chemical class 0.000 description 1
- 150000001412 amines Chemical class 0.000 description 1
- 229910021529 ammonia Inorganic materials 0.000 description 1
- 239000013043 chemical agent Substances 0.000 description 1
- 235000019504 cigarettes Nutrition 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000006073 displacement reaction Methods 0.000 description 1
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- 125000002534 ethynyl group Chemical group [H]C#C* 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 229910000069 nitrogen hydride Inorganic materials 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000007650 screen-printing Methods 0.000 description 1
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- 238000001228 spectrum Methods 0.000 description 1
- 238000004528 spin coating Methods 0.000 description 1
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- XTQHKBHJIVJGKJ-UHFFFAOYSA-N sulfur monoxide Chemical class S=O XTQHKBHJIVJGKJ-UHFFFAOYSA-N 0.000 description 1
- 238000009423 ventilation Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
- 239000008096 xylene Substances 0.000 description 1
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- 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
- G01N27/4141—Ion-sensitive or chemical field-effect transistors, i.e. ISFETS or CHEMFETS specially adapted for gases
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
- G01N33/0004—Gaseous mixtures, e.g. polluted air
- G01N33/0009—General constructional details of gas analysers, e.g. portable test equipment
- G01N33/0027—General constructional details of gas analysers, e.g. portable test equipment concerning the detector
- G01N33/0036—General constructional details of gas analysers, e.g. portable test equipment concerning the detector specially adapted to detect a particular component
- G01N33/004—CO or CO2
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- 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
- G01N27/4141—Ion-sensitive or chemical field-effect transistors, i.e. ISFETS or CHEMFETS specially adapted for gases
- G01N27/4143—Air gap between gate and channel, i.e. suspended gate [SG] FETs
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- Pathology (AREA)
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Abstract
Es wird ein Gassensor zur Erfassung von Kohlendioxid in einem Gasgemisch angegeben, bei dem die Austrittsarbeit von mit Aluminium dotiertem Zinkoxid als Sensorsignal erfasst wird.A gas sensor for detecting carbon dioxide in a gas mixture is specified, in which the work function of zinc oxide doped with aluminum is recorded as a sensor signal.
Description
Die Erfindung betrifft einen Halbleiter-Gassensor. The invention relates to a semiconductor gas sensor.
Die Detektion von Kohlendioxid ist für eine Reihe von Applikationen von hohem Interesse. Beispiele sind die Beurteilung der Luftgüte in Innenräumen, energieeffizientes Ansteuern von Klimaanlagen oder die Kontrolle gereinigter Luft. Ziel der Detektion von Kohlendioxid kann eine Erhöhung des Komforts sein. Es ist aber auch möglich, unter Umständen erhebliche Energieeinsparungen zu erzielen. The detection of carbon dioxide is of great interest for a number of applications. Examples include the assessment of indoor air quality, energy-efficient control of air conditioning systems or the control of purified air. The goal of detecting carbon dioxide can be an increase in comfort. But it is also possible to achieve significant energy savings under certain circumstances.
So kann beispielsweise bei einem gut isolierten Gebäude nahezu die Hälfte der für eine Klimatisierung benötigten Energie durch eine bedarfsgerechte Klimatisierung eingespart werden. Der Bedarf orientiert sich dabei unter anderem am Kohlendioxid-Gehalt der Luft. Auch im Automobilbereich ist eine bedarfsgerechte Belüftung und Klimatisierung des Fahrgastinnenraums vorteilhaft. Ein Schätzwert für die Reduzierung des Verbrauchs für die Klimatisierung beträgt 0,3 l auf 100 km. For example, in a well-insulated building, almost half of the energy needed for air-conditioning can be saved by means of demand-based air conditioning. The demand is based, among other things, on the carbon dioxide content of the air. Also in the automotive sector needs-based ventilation and air conditioning of the passenger compartment is advantageous. An estimate of the reduction in air conditioning consumption is 0.3 l per 100 km.
Kohlendioxid tritt bei normalen Umgebungsbedingungen in der Luft in einer Konzentration von ca. 380–400 ppm auf. Ein Sensor für Kohlendioxid muss ausgehend von dieser Basiskonzentration in der Lage sein, erhöhte Konzentrationen bis beispielsweise 4000 ppm zu detektieren. Problematisch ist dabei, dass das Kohlendioxidmolekül ein lineares, symmetrisches Molekül ist und daher kein elektrisches Dipolmoment vorhanden ist, welches bei verschiedenen Transducer-Prinzipien ein Sensorsignal bewirken kann. Weiterhin ist das Molekül chemisch sehr unreaktiv. Carbon dioxide occurs in normal ambient conditions in the air in a concentration of about 380-400 ppm. A sensor for carbon dioxide must be able to detect elevated concentrations, for example 4000 ppm, starting from this basic concentration. The problem here is that the carbon dioxide molecule is a linear, symmetric molecule and therefore no electrical dipole moment is present, which can cause a sensor signal at different transducer principles. Furthermore, the molecule is chemically very unreactive.
Momentan sehr erfolgreiche Methoden zur Konzentrationsbestimmung von Kohlendioxid sind daher vor allem im Bereich der optischen Spektroskopie zu finden. Hierbei wird ausgenutzt, dass Kohlendioxid in bestimmten Wellenlängenbereichen, beispielsweise bei etwa 4,3 µm Wellenlänge, Licht absorbiert. Hierdurch ist eine genaue und selektive Messung der Konzentration von Kohlendioxid möglich. Dabei kommt es auf die chemische Reaktivität des Kohlendioxids nicht an. Nachteilig an der optischen Spektroskopie sind jedoch der komplexe Aufbau der Messsysteme und der erhebliche Aufwand, der zur Auswertung der gemessenen Spektren erforderlich ist. Das führt letztlich zu verhältnismäßig großen und teuren Messsystemen. At present, very successful methods for determining the concentration of carbon dioxide are therefore to be found above all in the field of optical spectroscopy. This exploits the fact that carbon dioxide absorbs light in certain wavelength ranges, for example at a wavelength of approximately 4.3 μm. This allows an accurate and selective measurement of the concentration of carbon dioxide. It does not depend on the chemical reactivity of the carbon dioxide. A disadvantage of optical spectroscopy, however, is the complex structure of the measuring systems and the considerable effort required to evaluate the measured spectra. This ultimately leads to relatively large and expensive measuring systems.
Festkörpersensoren wie beispielsweise Halbleiter-Gassensoren vermeiden die Nachteile der optischen Messsysteme. Sie basieren beispielsweise auf der Vermessung des elektrischen Widerstands einer gassensitiven Schicht aus einem halbleitenden Material. Sie sind klein, durch Massenproduktion im Vergleich extrem billig herzustellen und benötigen eine weniger komplexe Signalauswertung. Nachteilig bei Festkörpersensoren ist jedoch, dass sie auf eine gewisse Reaktivität der zu messenden Moleküle angewiesen sind und gleichzeitig aber alle Moleküle detektieren, die eben eine gewisse Reaktivität aufweisen. Anders formuliert haben die Festkörpersensoren eine geringe Selektivität. Das macht vor allem die Messung wenig reaktiver Spezies wie Kohlendioxid mit solchen Sensoren schwierig, da sie meist sehr stark auf Kohlenwasserstoffe oder Ozon reagieren. Solid state sensors such as semiconductor gas sensors avoid the disadvantages of the optical measuring systems. They are based for example on the measurement of the electrical resistance of a gas-sensitive layer made of a semiconducting material. They are small by mass production compared to produce extremely cheap and require a less complex signal evaluation. A disadvantage of solid state sensors, however, is that they are dependent on a certain reactivity of the molecules to be measured and at the same time detect all molecules that have just a certain reactivity. In other words, the solid-state sensors have a low selectivity. This makes it difficult, above all, to measure less reactive species such as carbon dioxide with such sensors, since they usually react very strongly to hydrocarbons or ozone.
Die Reihe der potentiellen Störgase ist dabei umfangreich. Sie umfasst Stickstoffdioxid (NO2), Kohlenmonoxid (CO) und Wasserstoff (H2), Ammoniak (NH3), Ethanol oder Salzsäuren (HCl), Stickstoffmonoxid (NO), Schwefeloxide (SOx), Kohlenoxidsulfid (COS), Lachgas (N2O) und Blausäure (HCN), Wasser (H2O) sowie organische Gase wie Methan, Ethan, Ethen, Acetylen und andere Kohlenwasserstoffe wie Formaldehyd (CH2O). Weitere Störgase sind Amine (NH2R1, NH1R2, NR3), Amide (RC(O)NH2, RC(O)NHR', RC(O)NR'R), Acrolein (C3H4O) und Phosgen (COCl2), Aromate wie Benzol (C6H6), Ethylbenzol, Chlorbenzol, Toluol, Xylol, Styrol und Phenol (C6H6O). Des Weiteren gibt es Ozon (O3) und die große Gruppe der VOCs (volatile organic compounds). The series of potential interfering gases is extensive. It includes nitrogen dioxide (NO2), carbon monoxide (CO) and hydrogen (H2), ammonia (NH3), ethanol or hydrochloric acids (HCl), nitric oxide (NO), sulfur oxides (SOx), carbon dioxide sulfide (COS), nitrous oxide (N2O) and hydrogen cyanide (HCN), water (H2O) and organic gases such as methane, ethane, ethene, acetylene and other hydrocarbons such as formaldehyde (CH2O). Other interfering gases are amines (NH2R1, NH1R2, NR3), amides (RC (O) NH2, RC (O) NHR ', RC (O) NR'R), acrolein (C3H4O) and phosgene (COCl2), aromatics such as benzene ( C6H6), ethylbenzene, chlorobenzene, toluene, xylene, styrene and phenol (C6H6O). There are also ozone (O3) and the large group of volatile organic compounds (VOCs).
Diese Gase treten teilweise schon in der normalen Umgebungsluft auf, beispielsweise Ozon. Weitere Quellen für Gase sind Brände, Zigarettenrauch, menschliche Aktivität, die Verwendung chemischer Mittel wie Putzmittel, offenstehende Nahrungsmittel oder technische Geräte wie Drucker. Auch Straßenverkehr und sogar die Wetterverhältnisse führen zum Auftreten von Gasen. Some of these gases already occur in the normal ambient air, for example ozone. Other sources of gases include fires, cigarette smoke, human activity, the use of chemical agents such as cleansers, open food or technical equipment such as printers. Road traffic and even the weather conditions lead to the appearance of gases.
Nachteilig an den bekannten Festkörpersensoren ist, dass für die erfolgreiche Detektion von Gasen typischerweise eine Beheizung ihrer gassensitiven Schicht notwendig ist. Diese erfordert einen andauernden Einsatz von elektrischer Leistung, was den Einsatz solcher Sensoren in energieautarken Systemen praktisch verhindert. A disadvantage of the known solid-state sensors is that heating of their gas-sensitive layer is typically necessary for the successful detection of gases. This requires a continuous use of electrical power, which practically prevents the use of such sensors in energy self-sufficient systems.
Es ist Aufgabe der vorliegenden Erfindung, einen Gassensor anzugeben, der bei geringstem Energieaufwand eine Detektion von Kohlendioxid ermöglicht. Eine weitere Aufgabe besteht darin, ein Herstellungsverfahren für den Gassensor anzugeben. It is an object of the present invention to provide a gas sensor which enables detection of carbon dioxide with the least expenditure of energy. Another object is to provide a manufacturing method for the gas sensor.
Diese Aufgabe wird durch einen Gassensor mit den Merkmalen von Anspruch 1 gelöst. Die Aufgabe wird hinsichtlich des Herstellungsverfahrens durch ein Verfahren mit den Merkmalen von Anspruch 6 gelöst. Die abhängigen Ansprüche betreffen vorteilhafte Ausgestaltungen der Erfindung. This object is achieved by a gas sensor having the features of
Der erfindungsgemäße Gassensor zur Erfassung von Kohlendioxid in einem Gasgemisch umfasst ein Substrat mit einer Feldeffekttransistorstruktur, die ein Gate umfasst. Weiterhin umfasst der Gassensor eine gassensitive Schicht, deren elektronische Austrittsarbeit bei einer Wechselwirkung mit Kohlendioxid verändert wird, im Bereich des Gates der Feldeffekttransistorstruktur. Die gassensitive Schicht umfasst Zinkoxid (ZnO), Aluminium sowie Aluminiumoxid (Al2O3). Die Feldeffektstruktur ist ausgestaltet, die elektronische Austrittsarbeit der gassensitiven Schicht zu erfassen. The gas sensor according to the invention for detecting carbon dioxide in a gas mixture comprises a substrate having a field effect transistor structure comprising a gate. Furthermore, the gas sensor comprises a gas-sensitive layer whose electronic work function is changed in an interaction with carbon dioxide, in the region of the gate of the field effect transistor structure. The gas-sensitive layer comprises zinc oxide (ZnO), aluminum and aluminum oxide (Al 2 O 3 ). The field effect structure is configured to detect the electronic work function of the gas-sensitive layer.
Für die Erfindung wurde erkannt, dass Zinkoxid mit Aluminiumoxid als gassensitive Schicht, deren Austrittsarbeit vermessen wird, als Sensor für das wenig reaktive Kohlendioxid geeignet ist. Im Gegensatz zu Sensoren, die mit Vermessung des elektrischen Widerstands arbeiten (resistiv), funktioniert der erfindungsgemäße Sensor vorteilhaft und überraschend auch bei Raumtemperatur. Im Gegensatz zu typischen resistiven Sensoren ist dabei die Messung einigermaßen schnell möglich und das Sensorsignal reagiert auf die Kohlendioxidkonzentration reversibel. Eine ständige Beheizung ist daher unnötig und der Stromverbrauch des Sensors ist damit wesentlich geringer als der eines vergleichbaren resistiven Sensors. For the invention, it was recognized that zinc oxide with alumina as a gas-sensitive layer, whose work function is measured, is suitable as a sensor for the less reactive carbon dioxide. In contrast to sensors that work with measurement of the electrical resistance (resistive), the sensor according to the invention works advantageously and surprisingly even at room temperature. In contrast to typical resistive sensors, the measurement is reasonably fast and the sensor signal reacts reversibly to the carbon dioxide concentration. A constant heating is therefore unnecessary and the power consumption of the sensor is thus much lower than that of a comparable resistive sensor.
In einer Ausgestaltung des Gassensors ist das Gate der Feldeffekttransistorstruktur durch einen Luftspalt von der restlichen Feldeffekttransistorstruktur getrennt. In one embodiment of the gas sensor, the gate of the field effect transistor structure is separated from the rest of the field effect transistor structure by an air gap.
Bei dem erfindungsgemäßen Verfahren zur Herstellung eines Gassensors zur Erfassung von Kohlendioxid in einem Gasgemisch erfolgen die folgenden Schritte:
- – Bereitstellen eines Substrats, insbesondere Siliziumsubstrats, mit einer Feldeffekttransistorstruktur, die ein Gate umfasst,
- – Aufbringen einer ersten Schicht auf das Substrat im Bereich des Gates der Feldeffekttransistorstruktur, wobei die erste Schicht Zinkoxid und Aluminium zusammen mit einem organischen Bindemittel, beispielsweise Ethylzellulose, umfasst,
- – Tempern der ersten Schicht zur Erzeugung einer für Kohlendioxid empfindlichen gassensitiven Schicht, wobei dabei das Aluminium teilweise oxidiert wird.
- Providing a substrate, in particular a silicon substrate, with a field effect transistor structure comprising a gate,
- Applying a first layer to the substrate in the region of the gate of the field effect transistor structure, the first layer comprising zinc oxide and aluminum together with an organic binder, for example ethylcellulose,
- - Annealing the first layer to produce a sensitive to carbon dioxide gas-sensitive layer, wherein the aluminum is partially oxidized.
Das organische Bindemittel verbleibt dabei in der Schicht und sorgt für eine ausreichende Haftung auf dem Träger. Die gassensitive Schicht kann beispielsweise mit den bekannten Siebdruck- oder Spin-Coating-Verfahren aufgebracht werden. Daneben kann der ersten Schicht vor dem Aufbringen Glasfritte beigemischt werden. The organic binder remains in the layer and ensures sufficient adhesion to the support. The gas-sensitive layer can be applied, for example, by the known screen-printing or spin-coating methods. In addition, the first layer can be mixed with glass frit before application.
Weitere Vorteile und Einzelheiten der Erfindung werden anhand der Zeichnung erläutert. Dabei zeigen Further advantages and details of the invention will be explained with reference to the drawing. Show
Bei Verwendung des Gassensors dringen Gasmoleküle
Claims (3)
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
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DE102013207310.0A DE102013207310A1 (en) | 2013-04-23 | 2013-04-23 | gas sensor |
PCT/EP2014/058173 WO2014173918A1 (en) | 2013-04-23 | 2014-04-23 | Gas sensor having a field effect transistor structure and a sensitive layer comprising aluminum-doped zinc oxide |
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DE102013207310.0A DE102013207310A1 (en) | 2013-04-23 | 2013-04-23 | gas sensor |
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Citations (2)
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WO2005054869A1 (en) * | 2003-12-08 | 2005-06-16 | Postech Foundation | Biosensor comprising zinc oxide-based nanorod and preparation thereof |
US20080121946A1 (en) * | 2006-08-31 | 2008-05-29 | Youn Doo Hyeb | Method of forming sensor for detecting gases and biochemical materials, integrated circuit having the sensor, and method of manufacturing the integrated circuit |
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US5362975A (en) * | 1992-09-02 | 1994-11-08 | Kobe Steel Usa | Diamond-based chemical sensors |
DE102008048715B4 (en) * | 2008-09-24 | 2019-06-27 | Siemens Aktiengesellschaft | Improvement of the signal quality of field effect transistors having humidity sensors or gas sensors |
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2013
- 2013-04-23 DE DE102013207310.0A patent/DE102013207310A1/en not_active Withdrawn
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Patent Citations (2)
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WO2005054869A1 (en) * | 2003-12-08 | 2005-06-16 | Postech Foundation | Biosensor comprising zinc oxide-based nanorod and preparation thereof |
US20080121946A1 (en) * | 2006-08-31 | 2008-05-29 | Youn Doo Hyeb | Method of forming sensor for detecting gases and biochemical materials, integrated circuit having the sensor, and method of manufacturing the integrated circuit |
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