High-transparency cu / i-hfo transparent diode and method for manufacturing the same

Abstract

This invention belongs to the field of electronic information materials technology, and discloses a high-transmittance CuI / IHFO transparent diode and its fabrication method. First, indium oxide is modified by Hf doping according to an In₂O₃:HfO₂ molar ratio of 10:1, and a hafnium-doped indium oxide transparent conductive film with a thickness of 800-1000 nm is prepared by magnetron sputtering. Then, a P-type CuI film is prepared on the surface of the hafnium-doped indium oxide transparent conductive film, and finally, a metal Au electrode is prepared on the surface of the CuI film to obtain the CuI / IHFO transparent diode. The transparent diode prepared by this invention has the characteristics of high transmittance and low forward voltage, and the fabrication process is simple, showing good application prospects.

Description

Technical Field

[0001] This invention belongs to the field of electronic information materials technology, specifically, it relates to a transparent diode and its preparation method. Background Technology

[0002] Transparent transistors are gaining increasing attention as a foundation for applications such as next-generation transparent displays. Thin-film diodes (TFDs) are crucial devices for realizing electronic circuit functions, particularly energy conversion and selective switching. Current research on transparent diodes is relatively limited, mainly focusing on four types: pn junction diodes, Schottky junction diodes, metal-insulator-semiconductor junction diodes, and metal-insulator-metal junction diodes.

[0003] As one of the simplest semiconductor devices, the PN junction is widely used in the electronics industry; it is not only a fundamental component of all electronic devices such as LEDs and lasers, but also the basis of solar cells. With the deepening research into clean energy sources such as solar energy, while focusing on the output efficiency of solar cells, requirements have also been placed on their light transmittance. Therefore, improving the light transmittance of the PN junction, a fundamental component, has a significant impact on improving the light transmittance of solar cells. Summary of the Invention

[0004] This invention aims to solve the technical problems related to the transmittance of PN junctions, and provides a high-transmittance CuI / IHFO transparent diode and its preparation method. It has a low forward conduction voltage (0.32V), which allows more energy to be provided to the load terminal and improves the circuit working efficiency; the average transmittance of visible light is as high as 84.25%.

[0005] To solve the above-mentioned technical problems, the present invention is achieved through the following technical solution:

[0006] According to one aspect of the present invention, a high-transmittance CuI / IHFO transparent diode is provided, wherein indium oxide is modified by Hf element doping according to the molar ratio of In2O3:HfO2 = 10:1; a hafnium-doped indium oxide transparent conductive film with a thickness of 800-1000 nm is prepared by magnetron sputtering; a P-type CuI film is prepared on the surface of the hafnium-doped indium oxide transparent conductive film, and a metal Au electrode is prepared on the surface of the CuI film.

[0007] According to another aspect of the present invention, a method for fabricating a high-transmittance CuI / IHFO transparent diode is provided, comprising the following steps:

[0008] (1) Indium oxide powder and hafnium oxide powder are mixed at a molar ratio of 10:1 to prepare the target material;

[0009] (2) Place the pretreated substrate onto the magnetron sputtering sample stage, mount the target material prepared in step (1) onto the corresponding RF sputtering target, and then evacuate the background vacuum of the magnetron sputtering system to 6.0 × 10⁻⁶. -5 Pa ~ 4.0 × 10 -5 Pa;

[0010] (3) Hafnium-doped indium oxide transparent conductive thin films were prepared by magnetron sputtering using high-purity argon as the sputtering gas; the film thickness was controlled to be 800-1000 nm and the sputtering power was controlled to be 55-75 W.

[0011] (4) A CuI film is prepared on the surface of the hafnium-doped indium oxide transparent conductive film;

[0012] (5) Prepare a metal Au electrode on the surface of the CuI film.

[0013] Further, the target preparation in step (1) includes the following steps:

[0014] (a) Mix the prepared sample with deionized water and ball mill it;

[0015] (b) The raw materials obtained after ball milling in step (a) are dried and sieved to obtain a powder with uniform particles;

[0016] (c) Add a binder to the powder obtained in step (b), pass it through an 80-mesh sieve, and then press it into a blank using a powder tablet press;

[0017] (d) Remove the glue from the prepared green body;

[0018] (e) The degummed preform is placed in a muffle furnace for sintering to obtain the target material.

[0019] Furthermore, the mixing and ball milling time in step (a) is 12 hours; the drying in step (b) is infrared drying, and the drying temperature is 80-120℃; the binder in step (c) is PVA powder.

[0020] Further, the pretreatment in step (2) involves ultrasonically cleaning the glass substrate in acetone or alcohol and then drying it.

[0021] Furthermore, the sputtering pressure in step (3) is 1.0 Pa.

[0022] Furthermore, the argon gas mentioned in step (3) of step (3) has a purity of 99.99%.

[0023] Furthermore, the CuI thin film preparation in step (4) includes the following steps:

[0024] (a) Place the sample prepared in step (3) on the magnetron sputtering sample stage, mount the metal Cu target on the corresponding DC sputtering target, and then evacuate the background vacuum of the magnetron sputtering system to 6.0 × 10⁻⁶. -5 Pa ~ 4.0 × 10 -5 Pa; DC sputtering was performed using high-purity argon as the sputtering gas;

[0025] (b) The sample obtained in step (a) is placed in iodine powder for iodization.

[0026] Furthermore, in step (a), the DC sputtering current is 300mA and the DC sputtering time is 1min.

[0027] Further, the metal Au electrode preparation in step (5) is as follows: the sample prepared in step (5) is placed on a magnetron sputtering sample stage, and metal Au is electroplated using a vacuum coating machine to prepare the top electrode.

[0028] The beneficial effects of this invention are:

[0029] This invention uses indium oxide and hafnium oxide as target materials and employs magnetron sputtering to prepare an IHFO thin film by controlling the thickness and sputtering power. A p-type CuI thin film is then prepared on the IHFO film, and finally, a metal Au electrode is fabricated on the CuI film using a photomask to obtain a CuI / IHFO transparent diode. The transparent diode prepared by this invention has the characteristics of high transmittance and low forward voltage, and the fabrication process is simple, showing good application prospects. Attached Figure Description

[0030] Figure 1 This is a schematic diagram illustrating the effect of different film thicknesses on the sheet resistance, average transmittance, and FOM value of the hafnium-doped indium oxide transparent conductive film in Example 1.

[0031] Figure 2 This is a schematic diagram illustrating the effect of different sputtering powers on the FOM value of the hafnium-doped indium oxide transparent conductive film in Example 2.

[0032] Figure 3 The image shows the IV curve of the transparent diode obtained in Example 3.

[0033] Figure 4 The transmittance of the transparent diode obtained in Example 3 in the visible light region is given. Detailed Implementation

[0034] The present invention will be further described in detail below through specific embodiments. These embodiments will enable those skilled in the art to have a more comprehensive understanding of the present invention, but will not limit the present invention in any way.

[0035] The organic solvents acetone and alcohol used in the examples were commercially available analytical grade raw materials; the In2O3 and HfO2 powders used to make the target material were commercially available products.

[0036] Example 1

[0037] (1) Target material preparation

[0038] (a) Indium oxide yellow powder and hafnium oxide white powder are mixed in a molar ratio of 1:0.1, ball-milled for 12 hours, dried in the infrared at 80-120°C, passed through an 80-mesh sieve, and then pressed into a blank using a powder tablet press.

[0039] (b) Remove the glue from the prepared green body;

[0040] (c) The degummed preform is placed in a muffle furnace for sintering to obtain an IHFO target.

[0041] (2) Cleaning the substrate

[0042] The glass substrate is ultrasonically cleaned in an organic solvent and then dried in a nitrogen stream.

[0043] (3) Preparation of IHFO thin film

[0044] (a) Place the dried glass substrate from step (2) onto the magnetron sputtering sample stage, place the target material prepared in step (1) onto the corresponding RF sputtering target, and then evacuate the background vacuum of the magnetron sputtering system to 6.0×10-5Pa~4.0×10-5Pa.

[0045] (b) Using high-purity Ar as the sputtering gas, with a sputtering pressure of 1.0 Pa, a sputtering power of 55 W, and a sputtering temperature of 600 °C, hafnium-doped indium oxide transparent conductive thin films were prepared.

[0046] Hafnium-doped indium oxide transparent conductive films with thicknesses of 194 nm, 289 nm, 494 nm, 662 nm, 893 nm and 1198 nm were obtained by controlling the magnetron sputtering time.

[0047] Figure 1 This represents the calculated FOM value of the thin film. From... Figure 1 As can be seen, the FOM value of the film gradually increases with the increase of film thickness. When the film thickness is between 800-1000 nm, the film has a good FOM value; when the film thickness is 893 nm, the maximum FOM value is obtained, at which point the hafnium-doped indium oxide transparent conductive film has a sheet resistance of 12.2 Ω / sq and an average transmittance as high as 89.84%.

[0048] Example 2

[0049] Hafnium-doped indium oxide transparent conductive films were prepared according to the method in Example 1. The thickness of the hafnium-doped indium oxide transparent conductive films was 900 nm, and the sputtering power was 55 W, 65 W, 75 W, 85 W, and 95 W.

[0050] Figure 2 This represents the calculated FOM value of the thin film. From... Figure 2 As can be seen, the film has an excellent FOM value when the sputtering power is between 55-65W; when the sputtering power is 65W, the maximum FOM value of 0.06224 is obtained.

[0051] Example 3

[0052] On a hafnium-doped indium oxide transparent conductive film with a thickness of 893 nm and a sputtering power of 65 W, a CuI film and a top electrode were further prepared:

[0053] (4) Preparation of CuI thin film

[0054] (a) Place the sample prepared in step (3) on the magnetron sputtering sample stage, mount the metal Cu target on the corresponding DC sputtering target, and then evacuate the background vacuum of the magnetron sputtering system to 6.0 × 10⁻⁶. -5 Pa ~ 4.0 × 10 -5 Pa; High-purity Ar was used as the sputtering gas, the DC sputtering current was 300mA, and the DC sputtering time was 1min;

[0055] (b) Place the sample obtained in step (a) into iodine powder and react for 1 min;

[0056] (5) Fabrication of the top electrode

[0057] The sample prepared in step (4) is placed on a magnetron sputtering sample stage and Au metal is electroplated using a vacuum coating machine to prepare the top electrode;

[0058] Figure 3 The IV curves of the transparent diode obtained in Example 3 were tested using a semiconductor parameter tester. The upper left corner shows the IV curves between the Au electrode and the CuI and IHFO films, both of which are straight lines, indicating that there are ohmic contacts between the Au electrode and the CuI and IHFO films. The curve between the CuI and IHFO films is non-linear, indicating that the diode has rectification characteristics and a forward conduction voltage of 0.32V.

[0059] Figure 4 The transmittance of the transparent diode under visible light is calculated to be as high as 84.25% in the visible light region (380-780nm).

[0060] Repeatability tests showed that the prepared PN junction maintained relatively stable performance when the thickness was 800-1000 nm and the sputtering power was controlled within the range of 55-75 W.

[0061] Although the preferred embodiments of the present invention have been described above in conjunction with the accompanying drawings, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many specific modifications under the guidance of the present invention without departing from the spirit and scope of the claims, and these modifications all fall within the scope of protection of the present invention.

Claims

1. A high-transmittance CuI / IHFO transparent diode, characterized in that, Indium oxide was modified by Hf doping according to a molar ratio of In₂O₃:HfO₂ = 10:1; a hafnium-doped indium oxide transparent conductive film with a thickness of 800-1000 nm was prepared by magnetron sputtering; a P-type CuI film was prepared on the surface of the hafnium-doped indium oxide transparent conductive film, and a metal Au electrode was prepared on the surface of the P-type CuI film; and the following steps were followed to obtain the following: (1) Indium oxide powder and hafnium oxide powder are mixed at a molar ratio of 10:1 to prepare the target material; (2) Place the pretreated substrate onto the magnetron sputtering sample stage, place the target material prepared in step (1) onto the corresponding RF sputtering target, and then evacuate the background vacuum of the magnetron sputtering system to 6.0 × 10⁻⁶. -5 Pa ~ 4.0 × 10 -5 Pa; (3) Using high-purity argon as the sputtering gas, hafnium-doped indium oxide transparent conductive thin films were prepared by magnetron sputtering; the film thickness was controlled to be 800-1000 nm and the sputtering power was controlled to be 55-75 W. (4) A CuI film is prepared on the surface of the hafnium-doped indium oxide transparent conductive film; (5) Prepare a metal Au electrode on the surface of the CuI film.

2. A method for fabricating a high-transmittance CuI / IHFO transparent diode as described in claim 1, characterized in that, Includes the following steps: (1) Indium oxide powder and hafnium oxide powder are mixed at a molar ratio of 10:1 to prepare the target material; (2) Place the pretreated substrate onto the magnetron sputtering sample stage, place the target material prepared in step (1) onto the corresponding RF sputtering target, and then evacuate the background vacuum of the magnetron sputtering system to 6.0 × 10⁻⁶. -5 Pa ~ 4.0 × 10 -5 Pa; (3) Hafnium-doped indium oxide transparent conductive thin films were prepared by magnetron sputtering using high-purity argon as the sputtering gas; the film thickness was controlled to be 800-1000 nm and the sputtering power was controlled to be 55-75 W. (4) A CuI film is prepared on the surface of the hafnium-doped indium oxide transparent conductive film; (5) Prepare a metal Au electrode on the surface of the CuI film.

3. The method for fabricating a high-transmittance CuI / IHFO transparent diode according to claim 2, characterized in that, The target preparation in step (1) includes the following steps: (a) Mix the prepared sample with deionized water and ball mill; (b) The raw materials obtained after ball milling in step (a) are dried and sieved to obtain a powder with uniform particles; (c) Add a binder to the powder obtained in step (b), pass it through an 80-mesh sieve, and then press it into a blank using a powder tablet press; (d) Remove the glue from the prepared green body; (e) The degummed preform is placed in a muffle furnace for sintering to obtain the target material.

4. The method for fabricating a high-transmittance CuI / IHFO transparent diode according to claim 3, characterized in that, The mixing and ball milling time in step (a) is 12 hours; the drying in step (b) is infrared drying, and the drying temperature is 80~120℃; the binder in step (c) is PVA powder.

5. The method for fabricating a high-transmittance CuI / IHFO transparent diode according to claim 2, characterized in that, The pretreatment in step (2) involves ultrasonically cleaning the glass substrate in acetone or alcohol and then drying it.

6. The method for fabricating a high-transmittance CuI / IHFO transparent diode according to claim 2, characterized in that, The sputtering pressure in step (3) is 1.0 Pa.

7. The method for fabricating a high-transmittance CuI / IHFO transparent diode according to claim 2, characterized in that, The purity of the argon gas mentioned in step (3) is 99.99%.

8. The method for fabricating a high-transmittance CuI / IHFO transparent diode according to claim 2, characterized in that, The preparation of the CuI thin film in step (4) includes the following steps: (a) Place the sample prepared in step (3) on the magnetron sputtering sample stage, mount the metal Cu target on the corresponding DC sputtering target, and then evacuate the background vacuum of the magnetron sputtering system to 6.0 × 10⁻⁶. -5 Pa ~ 4.0 × 10 -5 Pa; DC sputtering was performed using high-purity argon as the sputtering gas; (b) The sample obtained in step (a) is placed in iodine powder for iodization.

9. The method for fabricating a high-transmittance CuI / IHFO transparent diode according to claim 8, characterized in that, In step (a), the DC sputtering current is 300 mA and the DC sputtering time is 1 min.

10. The method for fabricating a high-transmittance CuI / IHFO transparent diode according to claim 2, characterized in that, The preparation of the metal Au electrode in step (5) is as follows: the sample prepared in step (5) is placed on the magnetron sputtering sample stage, and metal Au is electroplated using a vacuum coating machine to prepare the top electrode.

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