CN102560635A - Preparation method of vanadium trioxide film - Google Patents
Preparation method of vanadium trioxide film Download PDFInfo
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- CN102560635A CN102560635A CN2012100762985A CN201210076298A CN102560635A CN 102560635 A CN102560635 A CN 102560635A CN 2012100762985 A CN2012100762985 A CN 2012100762985A CN 201210076298 A CN201210076298 A CN 201210076298A CN 102560635 A CN102560635 A CN 102560635A
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- oxide film
- vanadous oxide
- vanadium
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Abstract
The invention relates to a preparation method of a vanadium trioxide film, belonging to the technical field of materials. The preparation method of the vanadium trioxide film comprises the following steps of: adding a water-soluble polymer and a complexing stabilizer with an inorganic substance of metavanadate as a vanadium source to form a vanadium precursor solution with long-term stability; spinning by using the vanadium precursor solution and carrying out high-temperature heat treatment in a closed high-temperature high-pressure tube furnace to obtain the vanadium trioxide film. According to the preparation method of the vanadium trioxide film, the vanadium trioxide film with good structure and performance can be obtained, meanwhile, isopropanol which is used in the process of preparing the vanadium trioxide film in the traditional chemical solution method is replaced with water as a solvent, and therefore, the cost is lowered.
Description
Technical field
The invention belongs to the material technology field, relate to the preparation method of vanadous oxide film.
Technical background
Vanadous oxide (V
2O
3) can experience near temperature is reduced to 155K one change the phase transition process of isolator into by conductor, corresponding electric property and optical property also can be undergone mutation.These particular performances make it in devices such as thermal sensor, restrictor, optical switch, huge using value arranged.For microminiaturization and the chip type of realizing device, for the requirement of material, to realize filmization exactly.
At present, prepare the common method of vanadous oxide film thermal evaporation, electron beam evaporation, rf magnetron sputtering, pulsed laser deposition and chemical solution method or the like are arranged.Be compared to physical method, it is simple, easy and simple to handle that chemical solution method has equipment, and the film forming advantage of low-cost and high-quality big area obtains to pay close attention to widely.The report that present chemical solution method prepares the vanadous oxide film mainly contains and adopts Triisopropoxyvanadium(V) oxide as the vanadium source; Triisopropoxyvanadium(V) oxide is dissolved in three Virahols forms precursor liquid; Be spun on substrate surface repeatedly; Through sintering in reducing atmosphere, finally obtain the film of vanadous oxide at last.Yet adopt the common predictably sintering oven of this method; Burner hearth and atmosphere; Realize that accurate atmosphere control is not easy; Therefore in the process of this preparation, very occur the phase of the barium oxide of the complicacy of equilibrium ratio non-chemically easily, the controllability that has caused subsequent preparation technology is relatively poor and then influence the performance of final film with repeatability.Simultaneously, adopt organic Triisopropoxyvanadium(V) oxide as the vanadium source, need be with Virahol as solvent, cost is higher in industrial production.
Summary of the invention
The present invention aims to provide and a kind ofly prepares the method for vanadous oxide film based on the water solvent chemical solution method, and this method is through being dissolved in inorganic metavanadate in the water-soluble polymer solution, through spin coating, the final film forming of thermal treatment.In heat treatment process, adopt the HTHP tube furnace, thereby airtight being isolated with outside air of HTHP tube furnace can obtain accurate atmosphere control.The present invention can obtain structure, well behaved vanadous oxide film.Simultaneously, making water replace the traditional chemical solution method to prepare uses Virahol can effectively reduce cost as solvent in the vanadous oxide thin-film process.
The concrete technical scheme of the present invention is:
A kind of preparation method of vanadous oxide film may further comprise the steps:
Step 1: prepare inorganic metavanadate aqueous solutions of polymers.The water-soluble polymers (like polymine or polyethylene polyamine) that at first will have amino or imino group is water-soluble, obtains solution A; In solution A, add inorganic metavanadate then (like NaVO
3, KVO
3, Li VO
3Or NH
4VO
3), be stirred to dissolving fully, obtain yellow-brownish solution B; The last complexing agent (like YD 30 or oxalic acid) that adding has had stabilization in the solution B, ultrasonic, be stirred to the solution clear, obtain inorganic metavanadate polymers soln C.
Step 2: adopt ultra-filtration equipment, free ions among the inorganic metavanadate polymers soln of the elimination C, and adopt the mode of evaporation to remove portion water in the solution with enriching soln, obtain the polybenzazole precursor solution of vanadium.
Step 3: the substrate surface that the polybenzazole precursor solution of step 2 gained vanadium is spun on cleaning.If substrate adopts and the monocrystal chip of vanadous oxide lattice match can obtain epitaxially grown vanadous oxide film.The thickness of title product vanadous oxide film is controlled through multiple spin coating.
Step 4: with spin coating the monocrystal chip of polybenzazole precursor solution of step 2 gained vanadium place 650～900 ℃ environment, and more than 1 hour, obtain final vanadous oxide film after the cooling in thermal treatment under the reducing atmosphere.The implement device of said heat treatment process can adopt the HTHP tube furnace, and sintering air pressure should be more than 0.2MPa; Wherein reducing atmosphere can adopt the mixed gas of hydrogen and nitrogen.
Need to prove, when the inorganic metavanadate polymers soln of preparation (solution A), need not to require to control the amount ratio between water-soluble polymers, complexing agent and the inorganic metavanadate.If amino perhaps imino group is excessive, then the group in all complexing agents all can be linked in the polymer molecular chain; If complexing agent is excessive, though excessive complexing agent complexing the metavanadic acid radical ion also can be filtered out through step 2.In like manner, if inorganic metavanadate is excessive, excessive metavanadic acid radical ion also can be filtered out through step 2; If inorganic metavanadate is not excessive, then all the metavanadic acid radical ions can both be complexed in the polymer molecular chain and through ultrasonic, stirring is scattered among the inorganic metavanadate polymers soln C.
The present invention adopts the HTHP tube furnace in the thermal treatment sintering process, completely cut off fully to be communicated with atmospheric, has realized the accurately controlled of atmosphere through air pressure control.Wherein sintering air pressure should be controlled at more than the 0.2MPa
In sum, the preparation method of the vanadium dioxide film based on solution method provided by the invention can obtain structure, well behaved vanadous oxide film, has good process controllability and repeatability simultaneously.
Description of drawings
Fig. 1 is a schematic flow sheet of the present invention.
Fig. 2 is the V of the present invention's preparation
2O
3/ Al
2O
3The structure and composition analytical results of film.Wherein (a) is embodiment 1 gained V
2O
3/ Al
2O
3The XRD analysis result of film; (b) be embodiment 1 gained V
2O
3/ Al
2O
3The PHI scanning result of film; (c) be embodiment 2 gained V
2O
3/ Al
2O
3The XRD analysis result of film.
Fig. 3 is the V of the present invention's preparation
2O
3/ Al
2O
3The resistance of film-temperature survey curve.Wherein (a) is embodiment 1 gained V
2O
3/ Al
2O
3The resistance of film-temperature survey curve
Embodiment:
Embodiment 1:
1. get polymine 2.0g and in beaker, add the 30ml deionized water, be stirred to dissolving fully, add the sodium metavanadate of 1.2g again; Ultrasonic, be stirred to solution yellowish brown clear, then add YD 30 3.0g, be stirred to fully dissolving; Solution is by the faint yellow green that slowly is transformed into; The Amicon8050 type ultra-filtration equipment that uses U.S. Millipore company to produce, free ions in the elimination solution, the polybenzazole precursor solution of formation vanadium.
2. get the sapphire substrate of [0001] orientation, use the ultrasonic cleaning 2 minutes successively of Virahol, acetone and ethanol, dry up for use with nitrogen.
3. the polymers soln that configures is spin-coated on the sapphire substrate, gets rid of flatly with photoresist spinner, the photoresist spinner rotating speed is 30s for the 5000r/min time.Substrate behind the whirl coating places constant temperature oven baking 30 minutes, takes out in air and after the cooling, repeats the spin coating operation repeatedly.
4. put into ceramic boat to sample, be positioned in the flat-temperature zone of HTHP tube furnace (the brilliant OTF-1200X of section), logical mixed gas protected, the concrete component of mixed gas is 98% N
2Add 2% H
2, keep the tube furnace internal gas pressure more than 0.2MPa.Set thermal treatment process, be specially: be warmed up to 510 ℃ from room temperature, temperature rise rate is 1 ℃/min; , heat-up rate is 10 ℃/min; At 650 ℃ of insulation 180min; Reduce to room temperature from 650 ℃ and take out sample, rate of temperature fall is 5 ℃/min; Promptly make V
2O
3/ Al
2O
3Film.
5.V
2O
3/ Al
2O
3The evaluation of film
Utilize XRD that film is carried out θ-2 θ scanning, to V
2O
3/ Al
2O
3The structure and composition of film is analyzed, and shown in Fig. 2 (a), has prepared V at sapphire substrate
2O
3Film, and film is the outer oriented growth of face.Utilize PHI scanning to confirm the lattice match relation between film and the substrate, shown in Fig. 2 (b), show V
2O
3Matching relationship between film and the substrate is V
2O
3(001) //Al
2O
3(001), V
2O
3[110] //Al
2O
3[110].For the electric property of analysed film, we utilize standard Four probing pin probe and 2400 couples of V of KEITHLEY
2O
3Sheet resistance is analyzed, and is as shown in Figure 3, V
2O
3The resistance transformation curve of characteristic shows, has prepared all good high-quality epitaxial film from the structure to the performance.
Embodiment 2:
1. get polymine 2.0g and in beaker, add the 30ml deionized water, be stirred to dissolving fully, add the ammonium meta-vanadate of 2.0g again, ultrasonic, be stirred to solution yellowish brown clear, then add YD 30 3.0g, be stirred to dissolving fully.Use the mode of evaporation to go out the portion water in the solution, reach the purpose of enriching soln.(what present embodiment adopted is inorganic metavanadic acid ammonium salt, and the decomposition because ammonium ion and other organic components all can gasify in heat treatment process is so present embodiment need not to adopt ultra-filtration equipment that inorganic metavanadate polymers soln is carried out filter operation.)
2. get the sapphire substrate of [0001] orientation, use the ultrasonic cleaning 2 minutes successively of Virahol, acetone and ethanol, dry up for use with nitrogen.
3. the polymers soln that configures is spin-coated on the sapphire substrate, gets rid of flatly with photoresist spinner, the photoresist spinner rotating speed is 30s for the 5000r/min time.Behind the whirl coating substrate is taken off with tweezers, be positioned in the clean stainless steel box.Place constant temperature oven baking 30 minutes, take out in air and after the cooling, repeat the spin coating operation repeatedly.
4. put into ceramic boat to sample, be positioned in the flat-temperature zone of HTHP tube furnace (the brilliant OTF-1200X of section), logical mixed gas protected, the concrete component of mixed gas is 94% N
2Add 6% H
2, keep tube furnace internal gas pressure 0.9MPa.Set thermal treatment process, be specially: be warmed up to 510 ℃ from room temperature, temperature rise rate is 1 ℃/min; Heat-up rate is 10 ℃/min; At 900 ℃ of insulation 60min; Reduce to room temperature from 900 ℃ and take out sample, rate of temperature fall is 5 ℃/min; Promptly make V
2O
3/ Al
2O
3Film.
5.V
2O
3/ Al
2O
3The evaluation of film
Utilize XRD that film is carried out θ-2 θ scanning, to V
2O
3/ Al
2O
3The structure and composition of film is analyzed, and shown in Fig. 2 (c), has prepared V at [11-20] orientation sapphire substrate
2O
3Film, and film is the outer oriented growth of face.
Embodiment 3:
1. get polymine 2.0g and in beaker, add the 30ml deionized water, be stirred to dissolving fully, add the ammonium meta-vanadate of 2.0g again, ultrasonic, be stirred to solution yellowish brown clear, then add YD 30 3.0g, be stirred to dissolving fully.Use the mode of evaporation to go out the portion water in the solution, reach the purpose of enriching soln.(what present embodiment adopted is inorganic metavanadic acid ammonium salt, and the decomposition because ammonium ion and other organic components all can gasify in heat treatment process is so present embodiment need not to adopt ultra-filtration equipment that inorganic metavanadate polymers soln is carried out filter operation.)
2. get the sapphire substrate of [0001] orientation, use the ultrasonic cleaning 2 minutes successively of Virahol, acetone and ethanol, dry up for use with nitrogen.
3. the polymers soln that configures is spin-coated on the sapphire substrate, gets rid of flatly with photoresist spinner, the photoresist spinner rotating speed is 30s for the 5000r/min time.Behind the whirl coating substrate is taken off with tweezers, be positioned in the clean stainless steel box.Place constant temperature oven baking 30 minutes, take out in air and after the cooling, repeat the spin coating operation repeatedly.
4. put into ceramic boat to sample, be positioned in the flat-temperature zone of HTHP tube furnace (the brilliant OTF-1200X of section), logical mixed gas protected, the concrete component of mixed gas is 96% N
2Add 4% H
2, keep tube furnace internal gas pressure 0.6MPa.Set thermal treatment process, be specially: be warmed up to 510 ℃ from room temperature, temperature rise rate is 1 ℃/min; Heat-up rate is 10 ℃/min; At 800 ℃ of insulation 60min; Reduce to room temperature from 900 ℃ and take out sample, rate of temperature fall is 5 ℃/min; Promptly make V
2O
3/ Al
2O
3Film.
5.V
2O
3/ Al
2O
3The evaluation of film
Utilize XRD that film is carried out θ-2 θ scanning, to V
2O
3/ Al
2O
3The structure and composition of film is analyzed, and shown in Fig. 2 (c), has prepared V at [11-20] orientation sapphire substrate
2O
3Film, and film is the outer oriented growth of face.
Claims (6)
1. the preparation method of a vanadous oxide film may further comprise the steps:
Step 1: prepare inorganic metavanadate aqueous solutions of polymers; The water-soluble polymers that at first will have amino or imino group is water-soluble, obtains solution A; In solution A, add inorganic metavanadate then, be stirred to dissolving fully, obtain yellow-brownish solution B; The last complexing agent that adding has had stabilization in the solution B, ultrasonic, be stirred to the solution clear, obtain inorganic metavanadate polymers soln C;
Step 2: adopt ultra-filtration equipment, free ions among the inorganic metavanadate polymers soln of the elimination C, and adopt the mode of evaporation to remove portion water in the solution with enriching soln, obtain the polybenzazole precursor solution of vanadium;
Step 3: the substrate surface that the polybenzazole precursor solution of step 2 gained vanadium is spun on cleaning;
Step 4: with spin coating the monocrystal chip of polybenzazole precursor solution of step 2 gained vanadium place 650～900 ℃ environment, and more than 1 hour, obtain final vanadous oxide film after the cooling in thermal treatment under the reducing atmosphere; The implement device of said heat treatment process adopts the HTHP tube furnace, and sintering air pressure should be more than 0.2MPa; Wherein reducing atmosphere adopts the mixed gas of hydrogen and nitrogen.
2. the preparation method of vanadous oxide film according to claim 1 is characterized in that, the water-soluble polymers that has amino or imino group described in the step 1 is polymine or polyethylene polyamine.
3. the preparation method of vanadous oxide film according to claim 1 is characterized in that, inorganic metavanadate described in the step 1 is for being NaVO
3, KVO
3, Li VO
3Or NH
4VO
3
4. the preparation method of vanadous oxide film according to claim 1 is characterized in that, complexing agent described in the step 1 is YD 30 or oxalic acid.
5. the preparation method of vanadous oxide film according to claim 1 is characterized in that, substrate described in the step 3 is if the monocrystal chip of employing and vanadous oxide lattice match can obtain epitaxially grown vanadous oxide film.
6. the preparation method of vanadous oxide film according to claim 1 is characterized in that, the implement device of step 4 heat treatment process is the HTHP tube furnace; Wherein the mixed gas hydrogen 2～6% of hydrogen and nitrogen, contain nitrogen 94～98%.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107662946A (en) * | 2017-08-11 | 2018-02-06 | 攀枝花学院 | The preparation method of vanadium trioxide |
| CN108314083A (en) * | 2018-04-04 | 2018-07-24 | 河钢股份有限公司承德分公司 | A method of by preparing vanadium trioxide containing vanadium solution |
| CN110560078A (en) * | 2019-09-30 | 2019-12-13 | 陕西科技大学 | v-shaped groove2O3Preparation method of @ Ni difunctional composite electrocatalyst |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107662946A (en) * | 2017-08-11 | 2018-02-06 | 攀枝花学院 | The preparation method of vanadium trioxide |
| CN107662946B (en) * | 2017-08-11 | 2020-01-14 | 攀枝花学院 | Preparation method of vanadium trioxide |
| CN108314083A (en) * | 2018-04-04 | 2018-07-24 | 河钢股份有限公司承德分公司 | A method of by preparing vanadium trioxide containing vanadium solution |
| CN108314083B (en) * | 2018-04-04 | 2020-11-03 | 河钢股份有限公司承德分公司 | Method for preparing vanadium trioxide from vanadium-containing solution |
| CN110560078A (en) * | 2019-09-30 | 2019-12-13 | 陕西科技大学 | v-shaped groove2O3Preparation method of @ Ni difunctional composite electrocatalyst |
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Application publication date: 20120711 |