Tin oxide-based target material for high ultraviolet transmittance thin film and preparation method thereof

Abstract

The present invention belongs to the technical field of tin oxide-based target materials, and provides a tin oxide-based target material for high ultraviolet transmittance thin film and a preparation method thereof. 2 , a first doping component, a second doping component and a third doping component; the first doping component includes Ga 2 O 3 ,La 2 O 3 , Yb 2 O 3 、ZrO 2 , MgO, the second doping component includes Sb 2 O 3 , CuO, Y 2 O 3 、SiO 2 , ZnO, and the third doping component includes at least one of B, Ge, and Bi. The tin oxide-based target provided by the present invention is SnO 2 As the main element, it has lower cost than ITO target material, and under the synergistic effect of the first doping component, the second doping component and the third doping component, the tin oxide-based target material of the present invention is endowed with low resistance and high density, and the film prepared therefrom has high ultraviolet light transmittance.

Description

Technical Field

[0001] The invention belongs to the technical field of target material preparation, and in particular relates to a tin oxide-based target material used for a high ultraviolet transmittance film and a preparation method thereof. Background Art

[0002] Transparent conductive oxide (TCO) films have high visible light transmittance and low resistivity and are widely used in various optoelectronic devices. Among them, indium tin oxide (ITO) film has excellent optoelectronic properties and is the most widely used TCO film. Its typical composition is 90% indium oxide and 10% tin oxide. Its visible light transmittance is greater than 85% and its resistivity is as low as 10 -4 Ω·cm order of magnitude. However, indium is a rare metal with a high price, which leads to high production cost of ITO film and limits its large-scale application. In addition, ITO film has a small bandgap and has a UV cutoff (UV absorption rate greater than 85%), which leads to low UV transmittance and limits its application range.

[0003] Therefore, it is necessary to develop a low-cost, low-resistance, and tin oxide-based target suitable for high UV-transmitting thin films. Summary of the invention

[0004] The object of the present invention is to provide a tin oxide-based target material for high ultraviolet transmittance thin films and a preparation method thereof, aiming to solve the problems of high cost and low ultraviolet transmittance of TCO thin films made from existing ITO target materials.

[0005] In order to achieve the above-mentioned invention object, the technical solution adopted by the present invention is as follows:

[0006] In the first aspect, the present invention provides a tin oxide-based target material for use in high ultraviolet transmittance thin films, wherein the raw materials include SnO2, a first doping component, a second doping component and a third doping component; the first doping component includes at least one of Ga2O3, La2O3, Yb2O3, ZrO2 and MgO, the second doping component includes at least one of Sb2O3, CuO, Y2O3, SiO2 and ZnO, and the third doping component includes at least one of B, Ge and Bi.

[0007] In a second aspect, the present invention further provides a method for preparing a tin oxide-based target material for a high ultraviolet transmittance thin film, comprising the following steps:

[0008] The tin oxide powder and the first doping component are ball-milled and mixed, and then calcined to form a solid solution powder;

[0009] Ball-milling the solid solution powder, the second doping component, the third doping component, the dispersant and the binder to obtain a mixed slurry;

[0010] The mixed slurry is spray-granulated to form granulated powder;

[0011] isostatically pressing the granulated powder to form a green billet;

[0012] The green blank is subjected to a first sintering treatment and a second sintering treatment in sequence to obtain a tin oxide-based target.

[0013] Compared with the prior art, the present invention has the following beneficial effects:

[0014] The tin oxide-based target material for high ultraviolet transmittance thin film provided by the first aspect of the present invention uses SnO2 as the main element, which can significantly reduce the cost of the target material compared with the ITO target material; the first doping component is doped with a wide bandgap oxide to widen the bandgap width of SnO2 (bandgap is about 3.6eV), so that the film prepared by the tin oxide-based target material has a high ultraviolet transmittance; the second doping component is doped with a sintering-aiding oxide to promote the densification sintering of SnO2, and solve the problem that SnO2 has poor sintering characteristics and is difficult to densify at high temperatures; the third doping component is doped to reduce the resistivity and contact resistance of the target coating, specifically, Bi (bismuth) and B (boron) are doped to generate low melting point compounds as flux to promote The target material coating crystallizes, reduces defects to reduce scattering, thereby reducing carrier loss and improving mobility, and Bi located at the grain boundary can modify the carrier channel near the grain boundary, effectively promoting carrier transport, so doping Bi and B helps to reduce resistance; B atomic size is smaller than silicon and has high activity, so B can easily reversely penetrate into the gate line, Si and other functional layers to replace the silicon atoms in the functional layer to form doping, thereby forming ohmic contact, so doping B helps to reduce contact resistance; doping Ge can adjust the Fermi level of SnO2, change the work function of SnO2, and effectively improve the ohmic contact between SnO2 and the gate line, Si and other functional layers, so doping Ge helps to further reduce contact resistance. Therefore, under the synergistic effect of the first doping component, the second doping component and the third doping component, the tin oxide-based target material of the present invention is endowed with the advantages of low cost, low resistance and high density, and the film prepared therefrom also has the advantages of low resistance, low contact resistance and high ultraviolet transmittance, so that the application range is wider.

[0015] The second aspect of the present invention provides a method for preparing a tin oxide-based target material for a high ultraviolet transmittance film. The method comprises the following steps: firstly, tin oxide powder and a first doping component are ball-milled and mixed, and then calcined to form a solid solution powder, and then the tin oxide powder and a second doping component and a third doping component are ball-milled and mixed, and then spray granulated. This can prevent the formation of a variety of intermediate compounds during the sintering process, and the segregation phase is equal, which is beneficial to improving the structural uniformity of the target material. Firstly, the green blank is subjected to a first sintering treatment, and a vacuum atmosphere prevents oxidation of Ge, Bi, and B, so that single substances such as Ge, Bi, and B diffuse into the ceramic grain boundary, and a liquid phase is formed between solid phase particles, which can fill the gaps between solid phase particles and improve the target material density, and can also accelerate atomic migration and diffusion, and promote the bonding between solid phase particles, thereby improving the target material structural uniformity and accelerating the sintering process. Then, a second sintering treatment is performed, and an oxygen atmosphere is conducive to inhibiting the volatilization of components, so that the material reaction in the green blank is more complete, the bonding between particles is more firm, and the pores can be reduced, so that the target material is denser, and at the same time, it helps to accelerate the sintering process and shorten the sintering time. Therefore, the preparation method of the present invention can greatly improve the uniformity and densification of the target material structure, so that the prepared tin oxide-based target material has the advantages of low resistivity and high density. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope of the present invention.

[0017] Figure 1 is a cross-sectional SEM image of the tin oxide-based target material provided in Example 1 of the present invention;

[0018] Figure 2 It is the transmission spectrum of the thin film prepared by the tin oxide-based target material provided in Example 1 of the present invention. DETAILED DESCRIPTION

[0019] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0020] A first aspect of an embodiment of the present invention provides a tin oxide-based target material for use in high ultraviolet transmittance thin films, wherein the raw materials thereof include SnO2, a first doping component, a second doping component and a third doping component; the first doping component includes at least one of Ga2O3, La2O3, Yb2O3, ZrO2 and MgO, the second doping component includes at least one of Sb2O3, CuO, Y2O3, SiO2 and ZnO, and the third doping component includes at least one of B, Ge and Bi.

[0021] The method for preparing a tin oxide-based target material for a high ultraviolet transmittance film provided in an embodiment of the present invention comprises the following steps: firstly, tin oxide powder and a first doping component are ball-milled and mixed, and then calcined to form a solid solution powder, and then the tin oxide powder and a second doping component and a third doping component are ball-milled and mixed, and then spray granulated, so that a variety of intermediate compounds are prevented from being formed during the sintering process, and the segregation phase is equal, which is beneficial to improving the organizational uniformity of the target material; firstly, the green blank is subjected to a first sintering treatment, and a vacuum atmosphere is used to prevent oxidation of Ge, Bi, and B, so that single substances such as Ge, Bi, and B are diffused into the ceramic grain boundary, and a liquid phase is formed between solid phase particles, which can fill the gaps between solid phase particles and improve the density of the target material, and can also accelerate atomic migration and diffusion, and promote the bonding between solid phase particles, thereby improving the organizational uniformity of the target material and accelerating the sintering process; and then a second sintering treatment is carried out, and an oxygen atmosphere is beneficial to inhibiting the volatilization of components, so that the substance reaction in the green blank is more complete, the bonding between particles is more firm, and the pores can be reduced, so that the target material is denser, and at the same time it helps to accelerate the sintering process and shorten the sintering time. Therefore, the preparation method of the present invention can greatly improve the uniformity and densification of the target material structure, so that the prepared tin oxide-based target material has the advantages of low cost, low resistance and high density. In some embodiments, the third doping component is composed of B, Ge, and Bi. Under the synergistic effect of B, Ge, and Bi in this embodiment, it can reduce the resistance of the tin oxide-based target material coating film and reduce the contact resistance between the tin oxide-based target material coating film and the gate line, Si and other functional layers, thereby helping to improve the photoelectric conversion efficiency.

[0022] In some embodiments, based on the total weight of the tin oxide-based target material as 100%, SnO2 is 88-96.4%, the first doping component is 3-10%, the second doping component is 0.1-0.5%, and the third doping component is 0.5-1.5%. With the coordination of the specific contents of the components in this embodiment, the tin oxide-based target material of this embodiment has the advantages of low cost, low resistance, low contact resistance, high density, wide bandgap and high ultraviolet transmittance, so that the relative density of the tin oxide-based target material is above 98.5%, the bandgap width of the film prepared by the tin oxide-based target material is 3.6-5eV, and the average transmittance in the ultraviolet band is ≥80%.

[0023] A second aspect of an embodiment of the present invention provides a method for preparing a tin oxide-based target material for a high ultraviolet transmittance thin film, comprising the following steps:

[0024] S1: ball-milling the tin oxide powder and the first doping component and then calcining them to form a solid solution powder;

[0025] S2: ball-milling the solid solution powder, the second doping component, the third doping component, the dispersant and the binder to obtain a mixed slurry;

[0026] S3: spray granulating the mixed slurry to form granulated powder;

[0027] S4: isostatically pressing the granulated powder to form a green billet;

[0028] S5: performing a first sintering treatment and a second sintering treatment on the green blank in sequence to obtain a tin oxide-based target.

[0029] The method for preparing a tin oxide-based target material for a high ultraviolet transmittance film provided in an embodiment of the present invention comprises the following steps: firstly, tin oxide powder and a first doping component are ball-milled and mixed, and then calcined to form a solid solution powder, and then the tin oxide powder and a second doping component and a third doping component are ball-milled and mixed, and then spray granulated, so that a variety of intermediate compounds are prevented from being formed during the sintering process, and the segregation phase is equal, which is beneficial to improving the organizational uniformity of the target material; firstly, the green blank is subjected to a first sintering treatment, and a vacuum atmosphere is used to prevent oxidation of Ge, Bi, and B, so that single substances such as Ge, Bi, and B are diffused into the ceramic grain boundary, and a liquid phase is formed between solid phase particles, which can fill the gaps between solid phase particles and improve the density of the target material, and can also accelerate atomic migration and diffusion, and promote the bonding between solid phase particles, thereby improving the organizational uniformity of the target material and accelerating the sintering process; and then a second sintering treatment is carried out, and an oxygen atmosphere is beneficial to inhibiting the volatilization of components, so that the substance reaction in the green blank is more complete, the bonding between particles is more firm, and the pores can be reduced, so that the target material is denser, and at the same time it helps to accelerate the sintering process and shorten the sintering time. Therefore, the preparation method of the present invention can greatly improve the uniformity and densification of the target material structure, so that the prepared tin oxide-based target material has the advantages of low resistivity and high density.

[0030] In step S1, the calcination temperature is 450-650°C and the calcination time is 3-6 hours. The calcination temperature and time range are conducive to the formation of solid solution powder by tin oxide powder and the first doping component.

[0031] In some embodiments, the particle size of the solid solution powder is 1 to 5 μm; the particle size of the second doping component is 100 to 500 nm; the particle size of the third doping component is 50 to 100 nm; the particle size of the particles in the mixed slurry is ≤ 500 nm, preferably 200 to 500 nm. The particle size range of this embodiment helps to improve the sintering diffusion efficiency of the mixed material, reduce the number of pores, and improve the organizational uniformity and density of the target material; if the particle size is too small and the specific surface area is too large, the elastic aftereffect of the pressing molding is too large, and the green body is prone to cracking during the sintering process; if the particle size is too large and the specific surface area is too small, the particle migration distance during sintering is long, which is not conducive to sintering, and is prone to poor solid solution, uneven component distribution, and poor densification.

[0032] In step S2, the added amount of the dispersant is 0.3-0.5% of the total weight of the solid solution powder, the second doping component and the third doping component; the added amount of the binder is 0.4-1.5% of the total weight of the solid solution powder, the second doping component and the third doping component.

[0033] In some embodiments, the dispersant is selected from polyethylene glycol; and the binder is selected from polyvinyl alcohol and / or polyethylene.

[0034] In some embodiments, the solid content of the mixed slurry is 60-70%.

[0035] In step S3, the inlet temperature of the spray granulation is 180-220°C, and the outlet temperature is 80-100°C.

[0036] In step S4, the isostatic pressing step includes: performing cold isostatic pressing at a pressure of 50 to 250 MPa.

[0037] In step S5, the first sintering treatment is performed in a vacuum atmosphere with a vacuum degree of 0.01-10Pa, a sintering temperature of 600-900°C, and a sintering time of 48-72h. The green blank is first subjected to vacuum sintering to prevent oxidation of single substances such as Ge, Bi, and B before diffusion to the ceramic grain boundaries, which is conducive to uniform diffusion to the ceramic grain boundaries and the formation of a liquid phase between solid phase particles, which can not only fill the gaps between solid phase particles and increase the density of the target material, but also accelerate atomic migration and diffusion, and promote the bonding between solid phase particles, thereby improving the uniformity of the target material structure and accelerating the sintering process.

[0038] In some embodiments, the second sintering process is performed in an oxygen atmosphere, with a pressure of 0.05-0.1 MPa, a sintering temperature of 1300-1600° C., and a sintering time of 12-36 hours. Oxygen sintering can further promote the densification of the target material and increase the density of the target material.

[0039] The following describes the invention in conjunction with specific embodiments.

[0040] Example 1

[0041] The present embodiment provides a tin oxide-based target material for use in a high ultraviolet transmittance thin film and a preparation method thereof.

[0042] A method for preparing a tin oxide-based target material for a high ultraviolet transmittance film comprises the following steps:

[0043] S1: Weigh appropriate amounts of tin oxide powder, gallium oxide powder, antimony oxide powder and Ge powder according to the mass ratio of 92.7 / 6 / 0.3 / 1;

[0044] S2: adding tin oxide powder and gallium oxide powder into a ball mill mixer and mixing them evenly, and then calcining them at 550° C. for 5 h to form gallium tin oxide powder;

[0045] S3: Add gallium tin oxide powder, antimony oxide powder and Ge powder into a ball mill mixer filled with alcohol, then add polyethylene glycol and mix them evenly, then add polyvinyl alcohol and mix them evenly, and control the total solid content to about 60% to form a mixed slurry;

[0046] S4: introducing the mixed slurry into a centrifugal spray granulator with an inlet temperature of 180°C and an outlet temperature of 80°C to form granulated powder;

[0047] S5: The granulated powder is loaded into a stainless steel mold, preformed by a hydraulic press, and then cold isostatically pressed at a pressure of 120 MPa to form a green blank;

[0048] S6: Place the green blank in a sintering furnace, evacuate to a vacuum degree of 1Pa, heat to 750°C and sinter for 60h, then introduce oxygen to a pressure of 0.07MPa, heat to 1450°C and sinter for 24h. After machining, a tin oxide-based target of standard size is obtained.

[0049] After testing, the tin oxide-based target material includes 92.7% SnO2, 6% Ga2O3, 0.3% Sb2O3, and 1% Ge.

[0050] Example 2

[0051] The present embodiment provides a tin oxide-based target material for use in a high ultraviolet transmittance thin film and a preparation method thereof.

[0052] The difference between its preparation method and embodiment 1 is:

[0053] S1: Weigh appropriate amounts of tin oxide powder, zirconium oxide powder, zinc oxide powder and Ge powder according to the mass ratio of 92.7 / 6 / 0.3 / 1;

[0054] S2: adding tin oxide powder and zirconium oxide powder into a ball mill mixer and mixing them evenly, and then calcining them at 550° C. for 5 h to form tin oxide zirconium powder;

[0055] S3: Add tin oxide zirconium powder, zinc oxide powder and Ge single substance powder into a ball mill mixer filled with alcohol.

[0056] After testing, the tin oxide-based target material includes 92.7% SnO2, 6% ZrO2, 0.3% ZnO, and 1% Ge.

[0057] Example 3

[0058] The present embodiment provides a tin oxide-based target material for use in a high ultraviolet transmittance thin film and a preparation method thereof.

[0059] The difference between its preparation method and embodiment 1 is:

[0060] S1: Weigh appropriate amounts of tin oxide powder, gallium oxide powder, antimony oxide powder and Bi powder according to the mass ratio of 92.7 / 6 / 0.3 / 1;

[0061] S3: Add gallium tin oxide powder, antimony oxide powder and Bi powder into a ball mill mixer filled with alcohol.

[0062] After testing, the tin oxide-based target material includes 92.7% SnO2, 6% Ga2O3, 0.3% Sb2O3, and 1% Bi.

[0063] Example 4

[0064] The present embodiment provides a tin oxide-based target material for use in a high ultraviolet transmittance thin film and a preparation method thereof.

[0065] The difference between its preparation method and embodiment 1 is:

[0066] S1: Weigh appropriate amounts of tin oxide powder, gallium oxide powder, antimony oxide powder and B element powder according to the mass ratio of 92.7 / 6 / 0.3 / 1;

[0067] S3: Add gallium tin oxide powder, antimony oxide powder and B element powder into a ball mill mixer filled with alcohol.

[0068] After testing, the tin oxide-based target material includes 92.7% SnO2, 6% Ga2O3, 0.3% Sb2O3, and 1% B.

[0069] Example 5

[0070] The present embodiment provides a tin oxide-based target material for use in a high ultraviolet transmittance thin film and a preparation method thereof.

[0071] The difference between its preparation method and embodiment 1 is:

[0072] S1: Weigh appropriate amounts of tin oxide powder, gallium oxide powder, antimony oxide powder, Ge powder and Bi powder according to the mass ratio of 92.7 / 6 / 0.3 / 0.5 / 0.5;

[0073] S3: Add gallium tin oxide powder, antimony oxide powder, Ge single substance powder and Bi single substance powder into a ball mill mixer filled with alcohol.

[0074] After testing, the tin oxide-based target material includes 92.7% SnO2, 6% Ga2O3, 0.3% Sb2O3, 0.5% Ge, and 0.5% Bi.

[0075] Example 6

[0076] The present embodiment provides a tin oxide-based target material for use in a high ultraviolet transmittance thin film and a preparation method thereof.

[0077] The difference between its preparation method and embodiment 1 is:

[0078] S1: Weigh appropriate amounts of tin oxide powder, gallium oxide powder, antimony oxide powder, Ge powder, Bi powder, and B powder according to the mass ratio of 92.7 / 6 / 0.3 / 0.3 / 0.3 / 0.4;

[0079] S3: Add gallium tin oxide powder, antimony oxide powder, Ge single substance powder, Bi single substance powder and B single substance powder into a ball mill mixer filled with alcohol.

[0080] After testing, the tin oxide-based target material includes 92.7% SnO2, 6% Ga2O3, 0.3% Sb2O3, 0.3% Ge, 0.3% Bi, and 0.4% B.

[0081] Example 7

[0082] The present embodiment provides a tin oxide-based target material for use in a high ultraviolet transmittance thin film and a preparation method thereof.

[0083] The difference between its preparation method and embodiment 1 is:

[0084] S1: Weigh appropriate amounts of tin oxide powder, gallium oxide powder, zirconium oxide powder, antimony oxide powder, Ge powder, Bi powder, and B powder according to the mass ratio of 92.7 / 3 / 3 / 0.3 / 0.3 / 0.4;

[0085] S2: adding tin oxide powder, gallium oxide powder and zirconium oxide powder into a ball mill mixer and mixing them evenly, and then calcining them at 550° C. for 5 h to form tin oxide gallium zirconium powder;

[0086] S3: Add tin gallium zirconium oxide powder, antimony oxide powder, Ge single substance powder, Bi single substance powder and B single substance powder into a ball mill mixer filled with alcohol.

[0087] After testing, the tin oxide-based target material includes 92.7% SnO2, 3% Ga2O3, 3% ZrO2, 0.3% Sb2O3, 0.3% Ge, 0.3% Bi, and 0.4% B.

[0088] Example 8

[0089] The present embodiment provides a tin oxide-based target material for use in a high ultraviolet transmittance thin film and a preparation method thereof.

[0090] The difference between its preparation method and embodiment 1 is:

[0091] S1: Weigh appropriate amounts of tin oxide powder, gallium oxide powder, antimony oxide powder, zinc oxide powder, Ge powder, Bi powder, and B powder according to the mass ratio of 92.7 / 6 / 0.2 / 0.1 / 0.3 / 0.3 / 0.4;

[0092] S3: Add gallium tin oxide powder, antimony oxide powder, zinc oxide powder, Ge single substance powder, Bi single substance powder and B single substance powder into a ball mill mixer filled with alcohol.

[0093] After testing, the tin oxide-based target material includes 92.7% SnO2, 6% Ga2O3, 0.2% Sb2O3, 0.1% ZnO, 0.3% Ge, 0.3% Bi, and 0.4% B.

[0094] Example 9

[0095] The present embodiment provides a tin oxide-based target material for use in a high ultraviolet transmittance thin film and a preparation method thereof.

[0096] The difference between its preparation method and embodiment 1 is:

[0097] S6: Place the green blank in a sintering furnace, evacuate to a vacuum degree of 0.01 Pa, heat to 600°C and sinter for 48 hours, then introduce oxygen to a pressure of 0.05 MPa, heat to 1300°C and sinter for 12 hours.

[0098] After testing, the tin oxide-based target material includes 92.7% SnO2, 6% Ga2O3, 0.3% Sb2O3, and 1% Ge.

[0099] Example 10

[0100] The present embodiment provides a tin oxide-based target material for use in a high ultraviolet transmittance thin film and a preparation method thereof.

[0101] The difference between its preparation method and embodiment 1 is:

[0102] S6: Place the green blank in a sintering furnace, evacuate to a vacuum degree of 10Pa, heat to 900°C and sinter for 72h, then introduce oxygen to a pressure of 0.1MPa, heat to 1600°C and sinter for 36h.

[0103] After testing, the tin oxide-based target material includes 92.7% SnO2, 6% Ga2O3, 0.3% Sb2O3, and 1% Ge.

[0104] Embodiment 11

[0105] The present embodiment provides a tin oxide-based target material for use in a high ultraviolet transmittance thin film and a preparation method thereof.

[0106] The difference between its preparation method and embodiment 1 is:

[0107] S1: Weigh appropriate amounts of tin oxide powder, gallium oxide powder, antimony oxide powder and Ge powder according to the mass ratio of 88 / 10 / 0.5 / 1.5.

[0108] After testing, the tin oxide-based target material includes 88% SnO2, 10% Ga2O3, 0.5% Sb2O3, and 1.5% Ge.

[0109] Example 12

[0110] The present embodiment provides a tin oxide-based target material for use in a high ultraviolet transmittance thin film and a preparation method thereof.

[0111] The difference between its preparation method and embodiment 1 is:

[0112] S1: Weigh appropriate amounts of tin oxide powder, gallium oxide powder, antimony oxide powder and Ge powder according to the mass ratio of 96.4 / 3 / 0.1 / 0.5.

[0113] After testing, the tin oxide-based target material includes 96.4% SnO2, 3% Ga2O3, 0.1% Sb2O3, and 0.5% Ge.

[0114] Comparative Example 1

[0115] This comparative example provides a tin oxide-based target material and a preparation method thereof.

[0116] The difference between its preparation method and embodiment 1 is:

[0117] S1: Weigh appropriate amounts of tin oxide powder and gallium oxide powder in a mass ratio of 94 / 6;

[0118] S2: Add tin oxide powder and gallium oxide powder into a ball mill mixer filled with alcohol, then add polyethylene glycol and mix evenly, then add gelatin polyvinyl alcohol and mix evenly, and control the total solid content to about 60% to form a mixed slurry.

[0119] After testing, the tin oxide-based target material includes 94% SnO2 and 6% Ga2O3.

[0120] Comparative Example 2

[0121] This comparative example provides a tin oxide-based target material and a preparation method thereof.

[0122] The difference between its preparation method and embodiment 1 is:

[0123] S1: Weigh appropriate amounts of tin oxide powder, gallium oxide powder, and antimony oxide powder according to a mass ratio of 93.7 / 6 / 0.3;

[0124] S3: Add gallium tin oxide powder and antimony oxide powder into a ball mill mixer filled with alcohol, then add polyethylene glycol and mix evenly, then add gelatin polyvinyl alcohol and mix evenly, and control the total solid content to about 60% to form a mixed slurry.

[0125] After testing, the tin oxide-based target material includes 93.7% SnO2, 6% Ga2O3, and 0.3% Sb2O3.

[0126] Comparative Example 3

[0127] This comparative example provides a tin oxide-based target material and a preparation method thereof.

[0128] The difference between its preparation method and embodiment 1 is:

[0129] S1: Weigh appropriate amounts of tin oxide powder, gallium oxide powder, and Ge powder according to a mass ratio of 93 / 6 / 1;

[0130] S3: Add gallium tin oxide powder and Ge powder into a ball mill mixer filled with alcohol, then add polyethylene glycol and mix evenly, then add polyvinyl alcohol and mix evenly, and control the total solid content to about 60% to form a mixed slurry.

[0131] After testing, the tin oxide-based target material includes 93% SnO2, 6% Ga2O3, and 1% Ge.

[0132] Comparative Example 4

[0133] This comparative example provides a tin oxide-based target material and a preparation method thereof.

[0134] The difference between its preparation method and embodiment 1 is:

[0135] S1: Weigh appropriate amounts of tin oxide powder, beryllium oxide powder, cobalt oxide powder and Ni powder in a mass ratio of 92.7 / 6 / 0.3 / 1;

[0136] S2: adding tin oxide powder and beryllium oxide powder into a ball mill mixer, mixing them evenly, and then calcining them at 550° C. for 5 h to form tin oxide beryllium oxide powder;

[0137] S3: adding tin oxide beryllium powder, cobalt oxide powder and Ni elemental powder into a ball mill mixer filled with alcohol, then adding polyethylene glycol and mixing them evenly, then adding polyvinyl alcohol and mixing them evenly, and controlling the total solid content to about 60% to form a mixed slurry;

[0138] After testing, the tin oxide-based target material includes 92.7% SnO2, 6% BeO, 0.3% CoO, and 1% Ni.

[0139] Comparative Example 5

[0140] This comparative example provides a tin oxide-based target material and a preparation method thereof.

[0141] The difference between its preparation method and embodiment 1 is:

[0142] S6: Place the green blank in a sintering furnace, raise the temperature to 750°C and sinter for 60 hours under air conditions, then introduce oxygen to a pressure of 0.07 MPa, raise the temperature to 1450°C and sinter for 24 hours. After machining, a tin oxide-based target of standard size is obtained.

[0143] After testing, the tin oxide-based target material includes 92.7% SnO2, 6% Ga2O3, 0.3% Sb2O3, and 1% Ge.

[0144] Comparative Example 6

[0145] This comparative example provides a tin oxide-based target material and a preparation method thereof.

[0146] The difference between its preparation method and embodiment 1 is:

[0147] S2: Add tin oxide powder, gallium oxide powder, antimony oxide powder and Ge powder into a ball mill mixer filled with alcohol, then add polyethylene glycol and mix evenly, then add gelatin polyvinyl alcohol and mix evenly, and control the total solid content to about 60% to form a mixed slurry.

[0148] After testing, the tin oxide-based target material includes 92.7% SnO2, 6% Ga2O3, 0.3% Sb2O3, and 1% Ge.

[0149] Related performance test analysis:

[0150] 1. Use SEM to test the cross-sectional microstructure of tin oxide-based target materials. The test results are as follows: Figure 1 As shown, from Figure 1 It can be seen that the tin oxide-based target has good grain uniformity and high density.

[0151] 2. The actual density (ρ) of the tin oxide-based targets prepared in Examples 1, 6 and Comparative Examples 1 to 6 was tested using the Archimedean principle. 实际 ), the theoretical density (ρ) of the tin oxide-based target is calculated based on formula (I) 理论 ), so relative density = ρ 实际 / ρ 理论 ;

[0152] ρ={(C1 / 100) / ρ1+(C2 / 100) / ρ2+……+(C n / 100) / ρ n} -1 (I);

[0153] C1 to C2 in formula (I) n is the content of each component in each tin oxide-based target, ρ1~ρ n Corresponding to C1~C n Density of each component (g / cm 3 ).

[0154] 3. The tin oxide-based targets prepared in Examples 1, 6 and Comparative Examples 1 to 6 were coated by magnetron sputtering equipment. Specifically, a quartz plate was used as a substrate, and the quartz plate was cleaned, dried, and then placed in a magnetron sputtering vacuum chamber; the vacuum degree was drawn to 5×10- 4 Pa, high-purity argon gas was introduced as the working gas at a flow rate of 30 mL / min and the working pressure was 0.8 Pa, and then the tin oxide-based target was radio frequency sputtered for 30 min at a sputtering power of 50 W to obtain a thin film;

[0155] 1) Using four probes to test the resistivity of the thin film of the tin oxide-based target material prepared in Examples 1 and 6 and Comparative Examples 1 to 6;

[0156] 2) The contact resistance of the tin oxide-based targets prepared in Examples 1 and 6 and Comparative Examples 1 to 6 to the film was tested using the Kelvin test method; specifically, a low-temperature silver paste was first printed on both ends of the film to be tested, and a metal electrode was obtained by heat treatment at 210°C / 15min. Then, the voltage V1 between the metal electrode pair was measured, and then the short-circuit switch inside the voltage measuring instrument was turned off, and the voltage V2 between the metal electrode pair was measured in the same way, and then the contact resistance value of the film was calculated by the following formula:

[0157] Rc=(V1-V2) / I

[0158] 3) The average transmittance of each film was tested by UV-visible spectrophotometer, and the bandgap width (Eg) of each film was obtained by bandgap fitting;

[0159] The test results are shown in Table 1 below:

[0160] Table 1

[0161]

[0162]

[0163] It can be seen from Table 1 that the relative density of the tin oxide-based targets prepared in Examples 1 and 6 is significantly higher than that of the tin oxide-based targets prepared in Comparative Examples 1, 3 and 4. This is mainly due to the fact that the embodiments of the present invention use a second doping component to dope the sintering-aid oxide to solve the defect of poor sintering characteristics of SnO2 and promote the densification sintering of SnO2.

[0164] The resistivity of the corresponding films of the tin oxide-based target materials prepared in Examples 1 and 6 is significantly lower than the resistivity of the corresponding films of the tin oxide-based target materials prepared in Comparative Examples 1 to 6. This is mainly due to the fact that the embodiments of the present invention promote the crystallization of the target coating by doping Bi and B with the third doping component, reduce defects, reduce scattering effects, thereby reducing carrier losses and improving mobility, and Bi is located at the grain boundaries to modify the carrier channels near the grain boundaries, effectively promoting carrier transport, thereby reducing resistance.

[0165] The contact resistance of the corresponding films of the tin oxide-based targets prepared in Examples 1 and 6 is significantly lower than the contact resistance of the corresponding films of the tin oxide-based targets prepared in Comparative Examples 1, 2, and 4. This is mainly due to the fact that the B atoms doped in the embodiments of the present invention are smaller in size than silicon and have higher activity, which makes it easy for B to reversely penetrate into functional layers such as gate lines and Si to replace silicon atoms in the functional layers to form doping and ohmic contact, thereby reducing the contact resistance; doping with Ge adjusts the Fermi level of SnO2, changes the work function of SnO2, and effectively improves the ohmic contact between SnO2 and functional layers such as gate lines and Si, thereby also reducing the contact resistance.

[0166] The resistivity and contact resistance of the corresponding films of the tin oxide-based target materials obtained in Examples 1 and 6 are significantly lower than those of the corresponding films of the tin oxide-based target materials obtained in Comparative Example 5. This is mainly due to the fact that the embodiments of the present invention first vacuum sinter the green billet to prevent oxidation of elements such as Ge, Bi, and B, thereby promoting the uniform diffusion of elements such as Ge, Bi, and B into the ceramic grain boundaries, which is beneficial to reducing the resistivity and contact resistance.

[0167] from Figure 2 It can be seen from the transmission spectrum that the thin film prepared by the tin oxide-based target material provided in Example 1 has a high transmittance in the ultraviolet band and the visible band.

[0168] The above description is only a preferred embodiment of the present invention and is not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A method for preparing a tin oxide-based target material for a high ultraviolet transmittance thin film, characterized in that: The steps include: The tin oxide powder and the first doping component are ball-milled and mixed, and then calcined to form a solid solution powder; Ball-milling the solid solution powder, the second doping component, the third doping component, the dispersant and the binder to obtain a mixed slurry; The mixed slurry is spray-granulated to form granulated powder; isostatically pressing the granulated powder to form a green billet; The green blank is subjected to a first sintering treatment and a second sintering treatment in sequence to obtain a tin oxide-based target material; The first doping component includes at least one of Ga2O3, La2O3, Yb2O3, ZrO2, and MgO, the second doping component includes at least one of Sb2O3, CuO, Y2O3, SiO2, and ZnO, and the third doping component includes at least one of B, Ge, and Bi; Based on the total weight of the tin oxide-based target material as 100%, the SnO2 is 88-96.4%, the first doping component is 3-10%, the second doping component is 0.1-0.5%, and the third doping component is 0.5-1.5%; The first sintering treatment is performed in a vacuum atmosphere with a vacuum degree of 0.01-10 Pa, a sintering temperature of 600-900° C., and a sintering time of 48-72 h. The atmosphere of the second sintering treatment is oxygen, the pressure is 0.05-0.1 MPa, the sintering temperature is 1300-1600° C., and the sintering time is 12-36 hours.

2. The preparation method according to claim 1, characterized in that: The particle size of the solid solution powder is 1-5 μm; the particle size of the second doping component is 100-500 nm; the particle size of the third doping component is 50-100 nm; and the particle size of the particles in the mixed slurry is ≤500 nm.

3. The preparation method according to claim 1, characterized in that: The calcination treatment is carried out at a temperature of 450-650° C. and for a time of 3-6 hours.

4. The preparation method according to any one of claims 1 to 3, characterized in that The added amount of the dispersant is 0.3-0.5% of the total weight of the solid solution powder, the second doping component and the third doping component; And / or, the added amount of the binder is 0.4-1.5% of the total weight of the solid solution powder, the second doping component, and the third doping component.

5. The preparation method according to any one of claims 1 to 3, characterized in that The dispersant is selected from polyethylene glycol; The binder is selected from polyvinyl alcohol and / or polyethylene.

6. A tin oxide-based target material for use in high ultraviolet transmittance thin films, prepared by the preparation method according to any one of claims 1 to 5.

7. The tin oxide-based target material according to claim 6, characterized in that: The relative density of the tin oxide-based target material is greater than 98.5%; And / or, the bandgap width of the film prepared by the tin oxide-based target is 3.6~5eV; And / or, the average transmittance of the film prepared from the tin oxide-based target material in the ultraviolet band is ≥80%.

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