CN102778481B - Induction gate type amorphous metal oxide TFT gas sensor - Google Patents
Induction gate type amorphous metal oxide TFT gas sensor Download PDFInfo
- Publication number
- CN102778481B CN102778481B CN201110117657.2A CN201110117657A CN102778481B CN 102778481 B CN102778481 B CN 102778481B CN 201110117657 A CN201110117657 A CN 201110117657A CN 102778481 B CN102778481 B CN 102778481B
- Authority
- CN
- China
- Prior art keywords
- metal oxide
- tft
- gas
- gas sensor
- type amorphous
- 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.)
- Active
Links
Images
Abstract
The invention provides an induction gate type amorphous metal oxide TFT gas sensor which comprises a substrate, source and drain electrodes formed on the substrate, a TFT conductive film formed on the substrate and on a signal detection electrode, a gate insulating dielectric layer formed on the substrate and on the TFT conductive film and a top gate electrode formed on the gate insulating dielectric layer. The gas sensor is characterized in that the TFT conductive film comprises an amorphous metal-oxide semiconductor and the top gate electrode comprises a gas-sensitive metal-oxide semiconductor. According to the gas sensor provided by the invention, since the amorphous semiconductor is used as the TFT conductive film and a gas-sensitive metal-oxide semiconductor layer is used as the top gate electrode, the advantage of excellent uniform conductive performance of the amorphous oxide TFT and the advantages of gas adsorption and reaction characteristics of high-sensitivity metal oxides are combined, high-sensitivity monitoring of environmental gas can be carried out, online changes of active amplifying signals are realized, and therefore, the gas sensor with the advantages of high sensitivity, a large area, low cost and monolithic integration is formed.
Description
Technical field
The present invention relates to a kind of semiconductor sensor part, particularly relate to the semi-conductive gas sensor of amorphous metal oxide that a kind of efficient low cost large scale can be integrated.
Background technology
Along with the development of social life and industrial technology, gas sensor has more and more important effect in monitoring toxic and harmful, industrial gaseous waste, atmospheric pollution and raising food and human settlement's Environmental Protection Level.Main example application has NO in pair atmosphere
x, SO
x, CO
2deng the monitoring of harmful gas; The monitoring of CO during life is produced; To the detection of ethanol, methyl alcohol; Detection to vehicle exhaust etc.
Since the sixties in last century, metal-oxide semiconductor (MOS) gas sensor just with higher sensitivity, respond the advantage such as rapid and occupy the principal market of gas sensor.Initial gas sensor mainly adopts SnO
2, ZnO is gas sensitive, researched and developed again in recent years some new materials, except a small amount of single metal oxide materials, as WO
3, In
2o
3, TiO
2, A1
2o
3deng outside, the focus of exploitation mainly concentrates on composite metal oxide and potpourri metal oxide is as shown in table 1.
The metal oxide sensitive material that all kinds of detection gas of table 1 is corresponding
Metal oxide semiconductor sensor can be divided into two kinds of resistance-type and non-resistance-types ultimate principle.
SnO
2, ZnO constant resistance formula metal oxide semiconductor sensor ultimate principle be to utilize oxide semiconductor the adsorption of gas and catalysis double effect change the resistance characteristic of material to external world, thereby reach monitoring object, belong to surperficial control type, but the serviceability temperature of such semiconductor transducer is higher, at 200～500 ℃, just possesses greatly higher sensitivity.Some are improved one's methods is in basic material, to add some noble metals (as Ag, Au, Pb etc.), activator and adhesive A 1
2o
3, SiO
2, ZrO
2deng improving sensitivity, improve the response time, reduce working temperature, improve selectivity etc.The method of preparing these sensitive materials has sintering process, sol-gal process, chemical vapour deposition technique and physical deposition method etc.
Non-resistance-type metal-oxide semiconductor (MOS) gas sensor mainly comprises metal oxide semiconductor field effect tube type gas sensor and diode-type gas sensor etc.The quick Pd grid of hydrogen MOSEFT is the catalytic metal gate field-effect gas sensor being developed into the earliest, and in the time that hydrogen and Pd have an effect, the threshold voltage of FET will change with density of hydrogen, detect hydrogen with this.Adopt yttria-stabilized zirconia (YSZ) to make the grid of MOSFET, Pt can be made into the quick FET type of oxygen gas sensor as metal gate.The metal gate of MOSFET is removed, adopt La
0.7sr
0.3feO
3oxide semiconductor field effect pipe (OSFET) the formula gas sensor that nano thin-film has been made micron-scale, working and room temperature as grid has successfully been realized the detection to alcohol gas.
The gas sensitization principle of metal-oxide semiconductor (MOS) is that the physics, the chemical process that rely on gas molecule (atom) to produce in sull adsorption process are carried out perception gas, and this reaction is based upon on certain surface state.Gas can be divided into negative ion absorption and positive ion absorption in the absorption on oxide semiconductor film surface: when adatom produces negative ion absorption in the time that semiconductor surface is obtained electronics, when adatom produces positive ion absorption in the time that semiconductor surface is supplied with electronics.No matter be that electronics moves from semiconductor to adatom or moves to semiconductor from foreign atom, all will cause that band curvature changes work function and conductivity.Gas sensor is generally operational in air, wherein contains a large amount of oxygen, belongs to strong oxidizing property gas.Oxygen very easily enters physics and chemistry absorption on gas sensitive surface, comprise two kinds of physisorption and chemisorption, and under room temperature, this process is carried out slowlyer, if temperature is higher, O2-can be further converted to O-form.The activity of O-is very high, can be adsorbed on lip-deep other reducibility gas ionic group of gas sensitive and react rapidly, as C2H5OH etc., will the redox chemical reaction of generating polynomial, the extra electron that course of reaction produces enters conduction band, causes gas sensitive resistance variations; In addition, for intermediate oxide gas sensitive, except above-mentioned oxygen absorption, also there is OH-absorption, be conducive to adsorbent and carry out redox reaction at metal oxide surface, the electronics wherein discharging enters conduction band, causes the bending of gas sensitive resistance variations and surface energy band.
The change in resistance of monitoring gas sensitive needs higher reacting dose, the sensitivity that need to improve gas adsorption rate, surface reaction rate, total body surface area etc. and improve signal; Thereby but the electrology characteristic that utilizes the reacted electron exchange of gas sensory material adsorbed gas to change surface energy level to affect active device (field effect transistor) can be more effective pilot signal change, realize online active amplifying signal and change.
Summary of the invention
Therefore, the technical issues that need to address of the present invention are just to overcome the series of problems such as technique, cost, homogeneity, response efficiency, reaction velocity, working temperature and power consumption in existing film integrated-type gas sensor the amorphous oxide semiconductor material that is applied to detection of gas and the device architecture that a kind of novel high efficiency, low cost Large-Area-Uniform can be integrated are provided.
The invention provides a kind of induction grid type TFT gas sensor, comprising: substrate; Source-drain electrode, is formed on described substrate; TFT conductive film, is formed in described substrate and described signal detection electrode; Gate insulation dielectric layer, is formed on described substrate and described TFT conductive film; Top gate electrode, is formed on described gate insulation dielectric layer; It is characterized in that, described TFT conductive film comprises non-crystal oxide semiconductor, and described top gate electrode comprises gas-sensitive metal oxide semiconductor.
The present invention also provides a kind of induction grid type amorphous metal oxide TFT gas sensor, comprising: substrate; Back-gate electrode, is formed on described substrate; Gate insulation dielectric layer, is formed on described substrate and described back-gate electrode; TFT conductive film, is formed on described gate insulation dielectric layer; Source-drain electrode, is formed on described substrate and described TFT conductive film; Top gate spacer, is formed on described TFT conductive film and described source-drain electrode; Top gate electrode, is formed in the gate spacer of described top; It is characterized in that, described TFT conductive film comprises non-crystal oxide semiconductor, and described top gate electrode comprises gas-sensitive metal oxide semiconductor.
Wherein, described non-crystal oxide semiconductor comprises the zno-based semiconductor of mixing In, described in mix In zno-based semiconductor comprise InGaZnO, InZnO, HfInZnO, TaInZnO, ZrInZnO, YInZnO, A1InZnO, SnInZnO.Wherein, described in mix [In]/([In]+[the 3rd metal]) in the zno-based semiconductor of In atom counting than being 35%～80%, the atom of [Zn]/([In]+[Zn]) is counted than being 40%～85%.Wherein, each element atom counting is than being [In]: [the 3rd metal]: [Zn]: [O]=1: 1: 1: 1 or 1: 1: 1: 2 or 2: 2: 2: 1 or 1: 1: 1: 4.
Wherein, described non-crystal oxide semiconductor comprises In
2o
3, ZTO, ITO, ZnO, SnO
x.
Wherein, described non-crystal oxide semiconductor thickness is 1 to 10000nm.
Wherein, at the bottom of described substrate comprises the silicon wafer-based of surface for silicon chip, glass, quartz, plastics or the back hollow out of insulation course.
Wherein, the material of described source-drain electrode and/or described back-gate electrode comprises Mo, Pt, Al, Ti, Co, Au, Cu, polysilicon, TiN, TaN and combination thereof.
Wherein, the material of described gate insulation dielectric layer and/or described top gate spacer comprises silicon dioxide, silicon nitride, silicon oxynitride, high k material and combination thereof.
Wherein, described gas-sensitive metal oxide semiconductor is described non-crystal oxide semiconductor.Wherein, described gas-sensitive metal oxide semiconductor is polycrystalline state, monocrystalline state, crystallite state or granular potpourri.Wherein, described potpourri is the potpourri of monobasic metal oxide and/or binary metal oxide composition.Wherein, described monobasic metal oxide comprises SnO
x(x=1～2), ZnO, Fe
2o
3, La
2o
3, In
2o
3, Al
2o
3, WO
3, MoO
3, TiO
2, V
2o
5, Co
3o
4, Ga
2o
3, CuO, NiO and combination thereof.Induction grid type amorphous metal oxide TFT gas sensor as claimed in claim 13, wherein, described binary metal oxide comprises that general formula is ABO
3and A
2bO
4binary metal oxide, in wherein said general formula, A metal is selected from Y, La, Zn, Cd, Co, Mg and combination thereof, B metal is selected from Fe, Sn, Ti, In and combination thereof.Wherein, described gas-sensitive metal oxide semiconductor also contains doping metals, and described doping metals comprises Ag, Au, Pb, Pt and combination thereof.
According to gas sensor of the present invention, owing to having adopted amorphous semiconductor as TFT conductive film and having used gas-sensitive metal oxide semiconductor layer as top gate electrode, in conjunction with excellent homogeneous conductive characteristic and the gas absorption of high sensitive metal oxide and the advantage separately of response characteristic of non-crystal oxide TFT, can carry out high sensitivity to environmental gas and monitor and realize online active amplifying signal variation, form thus the integrated gas sensor of highly sensitive large area low cost monolithic.
Object of the present invention, and in these other unlisted objects, in the scope of the application's independent claims, met.Embodiments of the invention are limited in independent claims, and specific features is limited in its dependent claims.
Accompanying drawing explanation
Describe technical scheme of the present invention in detail referring to accompanying drawing, wherein:
Figure 1A is the diagrammatic cross-section according to induction grid type TFT gas sensor of the present invention;
Figure 1B is the top view according to induction grid type TFT gas sensor of the present invention;
Fig. 2 A is the diagrammatic cross-section according to induction grid type TFT gas sensor of the present invention; And
Fig. 2 B is the top view according to induction grid type TFT gas sensor of the present invention.
Reference numeral
1, substrate
2/2A/2B, source-drain electrode
3, TFT conductive film
4, gate insulation dielectric layer
5, top gate electrode
6, back-gate electrode
7, top gate spacer
Embodiment
The feature and the technique effect thereof that describe technical solution of the present invention in detail referring to accompanying drawing and in conjunction with schematic embodiment, disclose induction grid TFT gas sensor.It is pointed out that structure like similar Reference numeral representation class, term " first " used in the application, " second ", " on ", D score etc. can be used for modifying various device architectures.These modify the space, order or the hierarchical relationship that not imply unless stated otherwise institute's modification device architecture.
As shown in Figure 1A, for according to a kind of schematic diagram of responding to grid TFT gas sensor of the present invention, comprise substrate 1, source-drain electrode 2, TFT conductive film 3, gate insulation dielectric layer 4, top gate electrode 5.Wherein, substrate 1 is dielectric substrate and provides support, the silicon chip that its material is for example insulation course for surface (is preferably silicon-on-insulator SOI, also can on body silicon substrate, deposit or the laying of silicon dioxide is made in thermal oxide, can also on body silicon, form the insulation course of silicon nitride or silicon oxynitride), glass (can be doped to conventional boron-phosphorosilicate glass BPSG, also can be spin-coating glass SOG, glass substrate 1 preferably has rectangular shape to be suitable for cutting and large area manufacture), quartz, at the bottom of the silicon wafer-based of plastics (being preferably the composition with higher melt and hardness and good insulation properties) and back hollow out etc.Substrate 1 is tabular substantially, comprises a pair of first type surface, is also lower surface and upper surface, also comprises the side surface between upper and lower major surfaces.The upper surface of substrate 1 can have coarse structure, periodicity concaveconvex structure, so that enhancing bond strength, for example realize by common technologies such as rare HF acid wet etching or plasma etchings, can also form cushion to slow down stress or bonding coat to strengthen bond strength (cushion or bonding coat are not shown).
On the upper surface of substrate 1, form source-drain electrode 2, the mode that preferably adopts sputtering deposit, its material is for example Mo, Pt, Al, Ti, Co, Au, Cu etc., can be the other materials with conducting function in addition, for example doped polycrystalline silicon, such as metal nitride such as TiN, TaN etc.Can be first when preparation even sputtering deposit one deck electrode layer material, then carry out etching according to electrode domain and remove unwanted part.After etching, leave electrode 2A and the 2B of pair of opposing, form source-drain electrode.As shown in Figure 1B, source- drain electrode 2A and 2B are oppositely arranged, and are preferably formed as staggered pair of electrodes is for bias voltage and drawing, and form the source-drain area contact electrode of TFT device architecture.The shape of source- drain electrode 2A and 2B is not limited to shown in figure, can also be parallel or uneven straight line, broken line or curve, and the required electrology characteristic of concrete wiring basis signal detection means structure needs and sets.The end of two electrodes is formed with contact pad separately, for being connected with external circuit.The width of electrode 2A/2B and thickness need and set according to the electric property of measuring element structure and heating, and the width and the thickness that are not limited in Figure 1B all equates, but for the consideration of being convenient to sputtering technology control, are preferably that thickness is identical and width is adjustable.
On the upper surface of substrate 1 and source- drain electrode 2A and 2B, be formed with subsequently TFT conductive film 3 with the active area as TFT device architecture, determine according to the exposure window of gas to be measured in the region that forms TFT conductive film 3, for example, shown in Figure 1B rectangular area, but can be also other geometric configuratioies, for example triangle, parallelogram, trapezoidal, regular polygon, circular etc.TFT conductive film 3 is made up of non-crystal oxide semiconductor, can from table 1, select corresponding oxide semiconductor, particularly broad-band gap (>=2.0eV) non-crystal oxide semiconductor according to probe gas type difference.According to amorphous state MOS gas sensor that can be integrated of the present invention, it is to mix zno-based semiconductor or other binary non-crystal oxide semiconductor of In that its non-crystal oxide semiconductor is selected material, the zno-based semiconductor of mixing In is for example GafnZnO (IGZO), InZnO, HfInZnO, TaInZnO, ZrInZnO, YInZnO, AlInZnO, SnInZnO, and other binary or multicomponent amorphous oxide semiconductor are for example In
2o
3, ZTO, ITO, ZnO, SnO
x(x=1～2) etc.Wherein, the atom counting of mixing [In]/([In]+[the 3rd metal]) in the ZnO based semiconductor of In is than being 35%～80%, and the atom of [Zn]/([In]+[Zn]) is counted than being 40%～85%.Preferred each element atom counting is than being [In]: [the 3rd metal]: [Zn]: [O]=1: 1: 1: 1 or 1: 1: 1: 2 or 2: 2: 2: 1 or 1: 1: 1: 4 etc.In material, In atom outer-shell electron is main conduction electrons source, conduct electricity by adjacent oxygen room, Zn atom plays the effect of stablizing micro-cell configuration, thereby and grade in an imperial examination three adulterants such as other Ga, Hf, Ta, Zr, Y, Al, Sn start to control the generation rate in oxygen room changes semi-conductive conductance.Common method for making is magnetron sputtering method (Sputter), chemical vapour deposition technique (CVD), metal-organic chemical vapor deposition equipment method (MOCVD), molecular beam epitaxy (MBE), pulsed laser deposition (PLD), sol-gel process (SOL-GEL), hydro-thermal method etc., preferably uses in the present invention magnetron sputtering method.Control the parameter of its manufacturing process and control the semi-conductive material characteristic of the formed zno-based of mixing In, for example, select suitable Ar/O
2ratio, sputtering pressure, sputtering power, underlayer temperature, annealing time and temperature etc.Optimum condition: Ar/O
2=100: x, x:0～50; Air pressure 10～1000mtorr; Power 50～500W; Sputter underlayer temperature room temperature to 400 ℃; Anneal 100～450 ℃, 10min～10hr.Can need and be 1 to 10000nm for the thickness of TFT conductive film 3 that the susceptibility of gas to be measured need to be selected to form according to device electric property, be preferably 20 to 2000nm, especially 40 to 200nm, particularly 60nm.For other binary or multicomponent amorphous oxide semiconductor, can be controlled to membrane stage by reasonable adjustment atom counting ratio and splash-proofing sputtering process parameter, similar with the zno-based non-crystal oxide of mixing In, can for example obtain required non-crystal oxide semiconductor by adding the 3rd metal or being adjusted to film thickness, these technology are known conventional to those skilled in the art.
Then on substrate 1 and TFT conductive film 3, form gate insulation dielectric layer 4, for example come deposition of silica, silicon nitride, silicon oxynitride by the method for low temperature CVD or be for example hafnia, the contour k material of tantalum oxide, also can be the combination of these materials, array mode can be to mix or stacked.
The last gas-sensitive metal oxide semiconductor layer that forms on gate insulation dielectric layer 4 with the top gate electrode 5 as TFT device, for example, passes through sputtering deposit.The material of top gate electrode 5 can be the material identical with above-mentioned TFT conductive film 3, also be non-crystal oxide semiconductor, be in particular zno-based semiconductor or other binary non-crystal oxide semiconductor of mixing In, the zno-based semiconductor of mixing In is for example GaInZnO (IGZO), InZnO, HfInZnO, TaInZnO, ZrInZnO, YInZnO, AlInZnO, SnInZnO, and other binary or multicomponent amorphous oxide semiconductor are for example In
2o
3, ZTO, ITO, ZnO, SnO
x(x=1～2) etc.Wherein, the atom counting of mixing [In]/([In]+[the 3rd metal]) in the ZnO based semiconductor of In is than being 35%～80%, and the atom of [Zn]/([In]+[Zn]) is counted than being 40%～85%.Preferred each element atom counting is than being [In]: [the 3rd metal]: [Zn]: [O]=1: 1: 1: 1 or 1: 1: 1: 2 or 2: 2: 2: 1 or 1: 1: 1: 4 etc.
The material of top gate electrode 5 also can be different from TFT conductive film 3, for example, be polycrystalline state, monocrystalline state, crystallite state or granular potpourri, can comprise SnO
x(x=1～2), ZnO, Fe
2o
3, La
2o
3, In
2o
3, Al
2o
3, WO
3, MoO
3, TiO
2, V
2o
5, Co
3o
4, Ga
2o
3, the monobasic metal oxide such as CuO, NiO, and general formula is ABO
3(for example YFeO
3, LaFeO
3, ZnSnO
3, CdSnO
3, Co
2tiO
3) and A
2bO
4(for example MgFe
2o
4, CdFe
2o
4, CdIn
2o
4) etc. binary metal oxide, in wherein said general formula, A metal is selected from Y, La, Zn, Cd, Co, Mg etc., B metal is selected from Fe, Sn, Ti, In etc.The potpourri that also can comprise above-mentioned these materials and doping metals, described doping metals is selected from Ag, Au, Pb, Pt etc.
In this device, bottom is the source-drain electrode (being also signal detection electrode 2A and 2B) and active area part (being also TFT conductive film 3) that stacked non-crystal oxide TFT is leaked in source, offers the circuit function such as input and pre-amplification of sensor.On it, be extremely sensitive air-sensitive induction grid structures (being also gas-sensitive metal oxide semiconductor layer 5), as the top gate electrode structure of TFT.Ultimate principle is bending and the variation that utilizes metal oxide to produce electron exchange to the absorption of gas molecule (ion) and cause this material surface energy level, thereby cause the Work function Change of TFT gate electrode, and change threshold voltage and the sub-threshold-conducting characteristic of TFT, TFT signal is sharply changed, thus the sensitive variation of effective monitoring environmental gas.
In said structure, compare polycrystalline, crystalline state and crystallite semiconductor, amorphous semiconductor shows shortrange order, isotropy, making I skill is simple, easily makes large area conductive film, and the active area that is extremely conducive to basic TFT makes.Take typical material IGZO as example, ternary mixed type non-crystal oxide metal semiconductor IGZO is by In
2o
3, Ga
2o
3form with ZnO, energy gap, in 3.4eV left and right, is a kind of ionic amorphous state N-type semiconductor material.In
2o
3in In
3+can form 5S electron trajectory, be conducive to the high-speed transfer of charge carrier; Ga
2o
3there is very strong ionic link, can suppress the generation in O room; Zn in ZnO
2+can form stable tetrahedral structure, can make in theory metal oxide IGZO form the non crystalline structure of stable higher conduction.Non-crystal oxide semiconductor belongs to ionic amorphous semiconductor, and conduction is by the atom outer-shell electron cloud overlapping carrier transport of realizing mutually of large radius, thereby large (10～100cm2/Vs) of mobility.The thermal conductivity of this material is in 1.4W/cmK left and right simultaneously, thermal capacitance is 10J/molK left and right, (thermal conductivity is in 1.48W/cmK left and right for the thermal parameters of the very approaching polycrystalline silicon material as common heating electrode, thermal capacitance is 20.8J/molK left and right), thereby the non-crystal oxide TFT of the conduction gas sensitive that can effectively heat top grid makes it reaction sensitivity and improves, and after detection reaction effective reduction gas sensitive.
In addition, the zno-based semiconductor film material of the In of mixing used in the present invention can also be used for other field, for example ultraviolet detector etc., according to gas detector of the present invention can also with the integrated manufacture of these other semiconductor devices, further reduce cost and improved efficiency.
embodiment 2
As shown in Figure 2 A, for according to a kind of diagrammatic cross-section of responding to grid TFT gas sensor of the present invention, comprise.Wherein, as the silicon wafer-based of surface for the silicon chip of insulation course, back hollow out at the bottom of, on the substrate 1 of glass, quartz, plastics etc., first sputtering deposit is formed with back-gate electrode 6, its material is for example Mo, Pt, Al, Ti, Co, Au, Cu etc., can be the other materials with conducting function in addition, for example doped polycrystalline silicon, such as metal nitride such as TiN, TaN etc.On substrate 1 and back-gate electrode 6, be formed with gate insulation dielectric layer 4 subsequently, for example come deposition of silica, silicon nitride, silicon oxynitride by the method for low temperature CVD or be for example hafnia, the contour k material of tantalum oxide, also can be the combination of these materials, array mode can be to mix or stacked.On gate insulation dielectric layer 4, adopt sputter to form TFT conductive film 3 with the active area as TFT device architecture, determine according to the exposure window of gas to be measured in the region that forms TFT conductive film 3, for example, shown in Fig. 2 B rectangular area, but can be also other geometric configuratioies, for example triangle, parallelogram, trapezoidal, regular polygon, circular etc.TFT conductive film 3 is made up of non-crystal oxide semiconductor, can from table 1, select corresponding oxide semiconductor, particularly broad-band gap (>=2.0eV) non-crystal oxide semiconductor according to probe gas type difference.According to amorphous state MOS gas sensor that can be integrated of the present invention, it is to mix zno-based semiconductor or other binary non-crystal oxide semiconductor of In that its non-crystal oxide semiconductor is selected material, the zno-based semiconductor of mixing In is for example GaInZnO (IGZO), InZnO, HfInZnO, TaInZnO, ZrInZnO, YInZnO, AlInZnO, SnInZnO, and other binary or multicomponent amorphous oxide semiconductor are for example In
2o
3, ZTO, ITO, ZnO, SnO
x(x=1～2) etc.Wherein, the atom counting of mixing [In]/([In]+[the 3rd metal]) in the ZnO based semiconductor of In is than being 35%～80%, and the atom of [Zn]/([In]+[Zn]) is counted than being 40%～85%.Preferred each element atom counting is than being [In]: [the 3rd metal]: [Zn]: [O]=1: 1: 1: 1 or 1: 1: 1: 2 or 2: 2: 2: 1 or 1: 1: 1: 4 etc.
On TFT conductive film 3, again form source-drain electrode 2 by sputter, preferably adopt the mode of sputtering deposit, its material is for example Mo, Pt, Al, Ti, Co, Au, Cu etc., can be the other materials with conducting function in addition, for example doped polycrystalline silicon, such as metal nitride such as TiN, TaN etc.Can be first when preparation even sputtering deposit one deck electrode layer material, then carry out etching according to electrode domain and remove unwanted part.After etching, leave electrode 2A and the 2B of pair of opposing, form source-drain electrode.As shown in Figure 2 B, source- drain electrode 2A and 2B are oppositely arranged, and are preferably formed as staggered pair of electrodes is for bias voltage and drawing, and form the source-drain area contact electrode of TFT device architecture.Wherein, back-gate electrode 6 is generally runs parallel with source-drain electrode 2A/2B, although back-gate electrode 6 width shown in Fig. 2 B compared with little and spacing compared with having lap with source-drain electrode greatly and not, but also can make with reference to the device setting of common MOSFETs back-gate electrode 6 parts cover source-drain electrode 2A/2B, thereby the grid-source of formation, grid-leakage areal coverage (not shown in Fig. 2 B).The shape of source- drain electrode 2A and 2B is not limited to shown in figure, can also be parallel or uneven straight line, broken line or curve, and the required electrology characteristic of concrete wiring basis signal detection means structure needs and sets.The end of two electrodes is formed with contact pad separately, for being connected with external circuit.The width of electrode 2A/2B and thickness need and set according to the electric property of measuring element structure and heating, and the width and the thickness that are not limited in Fig. 2 B all equates, but for the consideration of being convenient to sputtering technology control, are preferably that thickness is identical and width is adjustable.
On TFT conductive film 3 and source-drain electrode 2, be formed with top gate spacer 7, its material and gate insulation dielectric layer 4 are similar, for example come deposition of silica, silicon nitride, silicon oxynitride by the method for low temperature CVD or be for example hafnia, the contour k material of tantalum oxide, also can be the combination of these materials, array mode can be to mix or stacked.
Finally, be formed with gas-sensitive metal oxide semiconductor layer with the top gate electrode as TFT device in top gate spacer 7, this top gate electrode is as the floating boom of TFT, for responding to the conduction electromotive force of controlling TFT back raceway groove.For example form by sputtering deposit.The material of top gate electrode can be the material identical with above-mentioned TFT conductive film 3, also be non-crystal oxide semiconductor, be in particular zno-based semiconductor or other binary non-crystal oxide semiconductor of mixing In, the zno-based semiconductor of mixing In is for example GaInZnO (IGZO), InZnO, HfInZnO, TaInZnO, ZrInZnO, YInZnO, AlInZnO, SnInZnO, and other binary or multicomponent amorphous oxide semiconductor are for example In
2o
3, ZTO, ITO, ZnO, SnO
x(x=1～2) etc.Wherein, the atom counting of mixing [In]/([In]+[the 3rd metal]) in the ZnO based semiconductor of In is than being 35%～80%, and the atom of [Zn]/([In]+[Zn]) is counted than being 40%～85%.Preferred each element atom counting is than being [In]: [the 3rd metal]: [Zn]: [O]=1: 1: 1: 1 or 1: 1: 1: 2 or 2: 2: 2: 1 or 1: 1: 1: 4 etc.
The material that forms the gas-sensitive metal oxide semiconductor layer of top gate electrode 5 also can be different from TFT conductive film 3, for example, be polycrystalline state, monocrystalline state, crystallite state or granular potpourri, can comprise SnO
x(x=1～2), ZnO, Fe
2o
3, La
2o
3, In
2o
3, Al
2o
3, WO
3, MoO
3, TiO
2, V
2o
5, Co
3o
4, Ga
2o
3, the monobasic metal oxide such as CuO, NiO, and general formula is ABO
3(for example YFeO
3, LaFeO
3, ZnSnO
3, CdSnO
3, Co
2tiO
3) and A
2bO
4(for example MgFe
2o
4, CdFe
2o
4, CdIn
2o
4) etc. binary metal oxide, in wherein said general formula, A metal is selected from Y, La, Zn, Cd, Co, Mg etc., B metal is selected from Fe, Sn, Ti, In etc.The potpourri that also can comprise above-mentioned these materials and doping metals, described doping metals is selected from Ag, Au, Pb, Pt etc.
In this device, bottom is that the conventional stacked of falling grid non-crystal oxide TFT structure comprises back-gate electrode, source-drain electrode and active area part, offers the circuit function such as input and pre-amplification of sensor.On it, be extremely sensitive air-sensitive induction grid structure, as the floating empty gate electrode structure at TFT top.This device is double-gated devices structure, and master control gate electrode is down grid, and top grid are used to change the conduction electromotive force of TFT back raceway groove.Ultimate principle is bending and the variation that utilizes metal oxide to produce electron exchange to the absorption of gas molecule (ion) and cause top grid gas sensitive surface energy level, thereby cause the Work function Change of TFT top gate electrode, and change thus threshold voltage and the sub-threshold-conducting characteristic of TFT, TFT signal is sharply changed, thus the sensitive variation of effective monitoring environmental gas.
In said structure, compare polycrystalline, crystalline state and crystallite semiconductor, amorphous semiconductor shows shortrange order, isotropy, manufacture craft is simple, easily makes large area conductive film, and the active area that is extremely conducive to basic TFT makes.Take typical material IGZO as example, ternary mixed type non-crystal oxide metal semiconductor IGZO is by In
2o
3, Ga
2o
3form with ZnO, energy gap, in 3.4eV left and right, is a kind of ionic amorphous state N-type semiconductor material.In
2o
3in In
3+can form 5S electron trajectory, be conducive to the high-speed transfer of charge carrier; Ga
2o
3there is very strong ionic link, can suppress the generation in O room; Zn in ZnO
2+can form stable tetrahedral structure, can make in theory metal oxide IGZO form the non crystalline structure of stable higher conduction.Non-crystal oxide semiconductor belongs to ionic amorphous semiconductor, and conduction is by the atom outer-shell electron cloud overlapping carrier transport of realizing mutually of large radius, thereby large (10～100cm2/V*s) of mobility.The thermal conductivity of this material is in 1.4W/cm*K left and right simultaneously, thermal capacitance is 10J/mol*K left and right, (thermal conductivity is in 1.48W/cm*K left and right for the thermal parameters of the very approaching polycrystalline silicon material as common heating electrode, thermal capacitance is 20.8J/mol*K left and right), thereby the non-crystal oxide TFT of the conduction gas sensitive that can effectively heat top grid makes it reaction sensitivity and improves, and after detection reaction effective reduction gas sensitive.
According to gas sensor of the present invention, owing to having adopted amorphous semiconductor as TFT conductive film and having used gas-sensitive metal oxide semiconductor layer as top gate electrode, in conjunction with excellent homogeneous conductive characteristic and the gas absorption of high sensitive metal oxide and the advantage separately of response characteristic of non-crystal oxide TFT, can carry out high sensitivity to environmental gas and monitor and realize online active amplifying signal variation, form thus the integrated gas sensor of highly sensitive large area low cost monolithic.
Although with reference to one or more exemplary embodiments explanation the present invention, those skilled in the art can know without departing from the scope of the invention device architecture is made to various suitable changes and equivalents.In addition, can make and manyly may be suitable for the modification of particular condition or material and not depart from the scope of the invention by disclosed instruction.Therefore, object of the present invention does not lie in and is limited to as the disclosed specific embodiment for realizing preferred forms of the present invention, and disclosed device architecture and manufacture method thereof will comprise all embodiment that fall in the scope of the invention.
Claims (15)
1. an induction grid type amorphous metal oxide TFT gas sensor, comprising:
Substrate;
Source-drain electrode, is formed on described substrate;
TFT conductive film, is formed on described substrate and described source-drain electrode;
Gate insulation dielectric layer, is formed on described substrate and described TFT conductive film;
Top gate electrode, is formed on described gate insulation dielectric layer;
It is characterized in that,
Described TFT conductive film comprises non-crystal oxide semiconductor, and described top gate electrode comprises gas-sensitive metal oxide semiconductor, and wherein, described non-crystal oxide semiconductor comprises the zno-based semiconductor or the In that mix In
2o
3, ZTO, ITO, ZnO, SnO
x.
2. an induction grid type amorphous metal oxide TFT gas sensor, comprising:
Substrate;
Back-gate electrode, is formed on described substrate;
Gate insulation dielectric layer, is formed on described substrate and described back-gate electrode;
TFT conductive film, is formed on described gate insulation dielectric layer;
Source-drain electrode, is formed on described substrate and described TFT conductive film;
Top gate spacer, is formed on described TFT conductive film and described source-drain electrode;
Top gate electrode, is formed in the gate spacer of described top;
It is characterized in that,
Described TFT conductive film comprises non-crystal oxide semiconductor, and described top gate electrode comprises gas-sensitive metal oxide semiconductor, and wherein, described non-crystal oxide semiconductor comprises the zno-based semiconductor or the In that mix In
2o
3, ZTO, ITO, ZnO, SnO
x.
3. induction grid type amorphous metal oxide TFT gas sensor as claimed in claim 1 or 2, wherein, described in mix In zno-based semiconductor comprise InGaZnO, InZnO, HfInZnO, TaInZnO, ZrInZnO, YInZnO, AlInZnO, SnInZnO.
4. induction grid type amorphous metal oxide TFT gas sensor as claimed in claim 3, wherein, in the zno-based semiconductor of the described In of mixing, the atom of [In]/([In]+[the 3rd metal]) counting is than being 35%～80%, and the atom of [Zn]/([In]+[Zn]) is counted than being 40%～85%.
5. induction grid type amorphous metal oxide TFT gas sensor as claimed in claim 4, wherein, each element atom counting is than being [In]: [the 3rd metal]: [Zn]: [O]=1:1:1:1 or 1:1:1:2 or 2:2:2:1 or 1:1:1:4.
6. induction grid type amorphous metal oxide TFT gas sensor as claimed in claim 1 or 2, wherein, described non-crystal oxide semiconductor thickness is 1 to 10000nm.
7. induction grid type amorphous metal oxide TFT gas sensor as claimed in claim 1 or 2, wherein, at the bottom of described substrate comprises the silicon wafer-based of surface for silicon chip, glass, quartz, plastics or the back hollow out of insulation course.
8. induction grid type amorphous metal oxide TFT gas sensor as claimed in claim 1 or 2, wherein, the material of described source-drain electrode and/or described back-gate electrode comprises Mo, Pt, Al, Ti, Co, Au, Cu, polysilicon, TiN, TaN and combination thereof.
9. induction grid type amorphous metal oxide TFT gas sensor as claimed in claim 1 or 2, wherein, the material of described gate insulation dielectric layer and/or described top gate spacer comprises silicon dioxide, silicon nitride, silicon oxynitride, high k material and combination thereof.
10. induction grid type amorphous metal oxide TFT gas sensor as claimed in claim 1 or 2, wherein, described gas-sensitive metal oxide semiconductor is described non-crystal oxide semiconductor.
11. induction grid type amorphous metal oxide TFT gas sensors as claimed in claim 1 or 2, wherein, described gas-sensitive metal oxide semiconductor is polycrystalline state, monocrystalline state, crystallite state or granular potpourri.
12. induction grid type amorphous metal oxide TFT gas sensors as claimed in claim 11, wherein, described potpourri is the potpourri of monobasic metal oxide and/or binary metal oxide composition.
13. induction grid type amorphous metal oxide TFT gas sensors as claimed in claim 12, wherein, described monobasic metal oxide comprises SnO
x, ZnO, Fe
2o
3, La
2o
3, In
2o
3, Al
2o
3, WO
3, MoO
3, TiO
2, V
2o
5, Co
3o
4, Ga
2o
3, CuO, NiO and combination, wherein x=1～2.
14. induction grid type amorphous metal oxide TFT gas sensors as claimed in claim 12, wherein, described binary metal oxide comprises that general formula is ABO
3and A
2bO
4binary metal oxide, in wherein said general formula, A metal is selected from Y, La, Zn, Cd, Co, Mg and combination thereof, B metal is selected from Fe, Sn, Ti, In and combination thereof.
15. induction grid type amorphous metal oxide TFT gas sensors as described in claim 12 to 14 any one, wherein, described gas-sensitive metal oxide semiconductor also contains doping metals, and described doping metals comprises Ag, Au, Pb, Pt and combination thereof.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201110117657.2A CN102778481B (en) | 2011-05-09 | 2011-05-09 | Induction gate type amorphous metal oxide TFT gas sensor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201110117657.2A CN102778481B (en) | 2011-05-09 | 2011-05-09 | Induction gate type amorphous metal oxide TFT gas sensor |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN102778481A CN102778481A (en) | 2012-11-14 |
| CN102778481B true CN102778481B (en) | 2014-06-11 |
Family
ID=47123461
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201110117657.2A Active CN102778481B (en) | 2011-05-09 | 2011-05-09 | Induction gate type amorphous metal oxide TFT gas sensor |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102778481B (en) |
Families Citing this family (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102738243B (en) * | 2012-06-06 | 2016-07-06 | 北京京东方光电科技有限公司 | Transistor, array base palte and manufacture method, liquid crystal panel and display device |
| JP6687862B2 (en) * | 2015-06-30 | 2020-04-28 | 富士通株式会社 | Gas sensor and method of using the same |
| JP6656507B2 (en) * | 2015-09-18 | 2020-03-04 | Ｔｉａｎｍａ Ｊａｐａｎ株式会社 | Biosensor and detection device |
| CN105304586A (en) * | 2015-11-20 | 2016-02-03 | 江阴长电先进封装有限公司 | Chip embedded-type encapsulation structure with reinforcing structure and encapsulation method of same |
| EP3465189A1 (en) * | 2016-05-27 | 2019-04-10 | Carrier Corporation | Gas detection device and method of manufacturing the same |
| CN106770499B (en) * | 2017-01-13 | 2021-05-18 | 京东方科技集团股份有限公司 | Carbon monoxide sensor, manufacturing method and control method thereof and smart television |
| CN108447915B (en) * | 2018-03-02 | 2020-11-24 | 华中科技大学 | Thin film field effect transistor type gas sensor and preparation method thereof |
| CN108847424B (en) * | 2018-04-24 | 2021-09-03 | 京东方科技集团股份有限公司 | Thin film transistor, sensor, biological detection device and method |
| CN110857928A (en) * | 2018-08-23 | 2020-03-03 | 吉福有限公司 | Semiconductor-type gas sensor, multi-sensor device, and method for identifying the same |
| KR20210085942A (en) * | 2019-12-31 | 2021-07-08 | 엘지디스플레이 주식회사 | Thin film transistor and display apparatus comprising the same |
| CN113447530B (en) * | 2021-02-26 | 2022-09-09 | 河南大学 | Gas sensing device |
| CN113193068B (en) * | 2021-05-08 | 2022-11-22 | 吉林大学 | Infrared photoelectric detector based on cobalt-doped lanthanum iron cobaltate nano film and manufacturing method thereof |
| CN117825458A (en) * | 2022-09-27 | 2024-04-05 | 华为技术有限公司 | Gas sensor and electronic device |
| CN115436436B (en) * | 2022-11-03 | 2023-03-10 | 南京元感微电子有限公司 | FET gas sensor and processing method thereof |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1528706A (en) * | 2003-10-10 | 2004-09-15 | 徐华蕊 | Y2O3 stable tetragonal phase ZrO2 monodisperse nano posder hydrothermal preparation method |
| CN1795377A (en) * | 2003-03-26 | 2006-06-28 | 纳幕尔杜邦公司 | Apparatus for analyzing mixtures of gases |
| CN101619499A (en) * | 2008-07-02 | 2010-01-06 | 中国科学院金属研究所 | Amorphous titanium oxide nanotube array structure and preparation method thereof |
-
2011
- 2011-05-09 CN CN201110117657.2A patent/CN102778481B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1795377A (en) * | 2003-03-26 | 2006-06-28 | 纳幕尔杜邦公司 | Apparatus for analyzing mixtures of gases |
| CN1528706A (en) * | 2003-10-10 | 2004-09-15 | 徐华蕊 | Y2O3 stable tetragonal phase ZrO2 monodisperse nano posder hydrothermal preparation method |
| CN101619499A (en) * | 2008-07-02 | 2010-01-06 | 中国科学院金属研究所 | Amorphous titanium oxide nanotube array structure and preparation method thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| CN102778481A (en) | 2012-11-14 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102778481B (en) | Induction gate type amorphous metal oxide TFT gas sensor | |
| CN102778479B (en) | Integratable amorphous metal oxide semiconductor gas sensor | |
| CN109900750B (en) | Structural design for improving sensitivity of MoS2 film field effect transistor-based gas sensor | |
| CN102856169B (en) | Preparation method of thin film transistor and top gate type thin film transistor | |
| CN110579526B (en) | Field effect transistor gas sensor and array preparation method thereof | |
| Cui et al. | High performance silicon nanowire field effect transistors | |
| CN106409841B (en) | A kind of circuit structure and production method and display pannel | |
| Choi et al. | Low voltage operating field effect transistors with composite In2O3–ZnO–ZnGa2O4 nanofiber network as active channel layer | |
| Sharma et al. | Ultra-low voltage metal oxide thin film transistor by low-temperature annealed solution processed LiAlO 2 gate dielectric | |
| Kim et al. | Highly dense and stable p-type thin-film transistor based on atomic layer deposition SnO fabricated by two-step crystallization | |
| Ditshego | ZnO nanowire field effect transistor for biosensing: A review | |
| CN107611180A (en) | A kind of vertical channel structure electric double layer thin film transistor (TFT) and preparation method thereof | |
| CN103500798A (en) | Gas sensor based on field effect transistor structure and preparation method thereof | |
| CN102403363A (en) | Double-layered oxide thin film transistor and preparation method thereof | |
| CN111060233A (en) | Piezoelectric type integrated flexible touch sensor and preparation method thereof | |
| CN101383291A (en) | Preparation of ZnO back gate nano line field effect tube | |
| CN103943683A (en) | Indium tin zinc oxide homogeneous thin film transistor and preparation method thereof | |
| CN104851935B (en) | A kind of Graphene/indium phosphide solar cell of electric field regulation and control and preparation method thereof | |
| CN103698365A (en) | Gas sensor and preparation method thereof | |
| Liang et al. | Optimization of two-dimensional channel thickness in nanometer-thick SnO2-based top-gated thin-film transistors using electric field thermopower modulation: implications for flat-panel displays | |
| Bukke et al. | Nano-scale Ga2O3 interface engineering for high-performance of ZnO-based thin-film transistors | |
| Liang et al. | Thickness optimization toward high-performance bottom-gated transparent tin dioxide thin-film transistors | |
| Trinh et al. | Solution-processed cupric oxide p-type channel thin-film transistors | |
| CN103545377B (en) | A kind of oxide thin film transistor and manufacture method thereof | |
| Dai et al. | Modeling novel double-in-plane gate electric-double-layer thin-film and nanoscale transistors |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |