TWI664307B - Transparent conductive film of indium zinc oxide / copper zirconium / indium zinc oxide - Google Patents

Abstract

The present invention is to provide a transparent conductive film of indium zinc oxide / copper zirconium / indium zinc oxide, which mainly deposits a target on a substrate, and the substrate is rotated in the sputtering process, so that the film has sufficient time for heat transfer. And improve the uniformity of the film, it is provided with a first indium zinc oxide (IZO) layer, which is sputter deposited on the substrate for 5 minutes; a second copper zirconium (Cu: Zr) layer, which is sputter deposited on the first indium zinc oxide (IZO) layer for 10 seconds. The copper-zirconium ratio of the second copper-zirconium (Cu: Zr) layer is copper (Cu): zirconium (Zr) = 80:20; the third indium zinc oxide (IZO) layer is Sputter deposition on the second copper-zirconium (Cu: Zr) layer for 5 minutes; thus, when the substrate is glass, it has a sheet resistance of 13.2 Ω / o, a light transmittance of 88%, and a photoelectric index of 1.68E ^-02 Ω ^-1 , reaching Best corrosion resistance, conductivity and light transmission.

Description

Transparent conductive film of indium zinc oxide / copper zirconium / indium zinc oxide

The invention relates to a transparent conductive film of indium zinc oxide / copper zirconium / indium zinc oxide, in particular, a target is sputter-deposited on a substrate, and the substrate is rotated in the sputtering process, so that the film has sufficient time for heat transfer. And improve the uniformity of the film, it is provided with: a first indium zinc oxide (IZO) layer, which is sputter deposited on the substrate for 5 minutes; a second copper zirconium (Cu: Zr) layer, which is sputter deposited on the first indium oxide Zinc (IZO) layer for 10 seconds, the copper-zirconium ratio of the second copper-zirconium (Cu: Zr) layer is copper (Cu): zirconium (Zr) = 80:20; the third indium zinc oxide (IZO) layer, The system is sputter-deposited on the second copper-zirconium (Cu: Zr) layer for 5 minutes; thus, when the substrate is glass, it has a sheet resistance of 13.2 Ω / o, a light transmittance of 88%, and a photoelectric index of 1.68E ^-02 Ω ^-1 To achieve the best corrosion resistance, conductivity and light transmission.

According to the current rapid development of the electronics and optoelectronic industries, all electronic products are moving towards the goal of lightness, thinness, shortness, and smallness. Among them, transparent conductive films are the most important components in optoelectronic products. Transparent conductive films Applications are very wide, such as: Solar Cell, Liquid Crystal Display (LCD), Light Emitting Diode (LED), Organic Light Emitting Diode (OLED), and Touch Panel, which are generally transparent Conductive film refers to the visible light range (wavelength 380 ~ 760nm) and requires high light transmittance (> 80%) and low resistivity (10 ^-3 Ω-cm), and high concentration of free carriers (about 10 ²⁰ / cm ³ ), and there are many kinds of materials for making transparent conductive films, which are roughly divided into two types: one is a metal thin film (such as gold, silver, copper, platinum, etc.), and the other is a metal oxide Semiconductors (ITO, GZO, AZO, etc.); because the metal itself is a good conductor, but does not have light transmission, if it is to grow into a metal film with light transmission, the thickness of the film must be less than 100Å (Å = 1 × 10 ^-10 m), but the thinner the film, the more likely it is to form a discontinuous island film, making it The conductivity decreases, so it is not suitable for use as a transparent conductive electrode; therefore, the present inventor has invented the present invention in the first place in view of the lack of knowledge as described above, and has concentrated on research and improvement.

The main purpose of the present invention is: a transparent conductive film of indium zinc oxide / copper zirconium / indium zinc oxide to achieve the best corrosion resistance, conductivity and light transmission.

The main feature of the present invention is that the first indium zinc oxide (IZO) layer is deposited on the substrate by radio frequency (RF) magnetron sputtering. The sputtering deposition time is 5 minutes, and the distance between the target and the substrate is 5 cm. The sputtering power is 125 watts; the second copper-zirconium (Cu: Zr) layer is a direct current (DC) magnetron sputtering deposited on the first indium zinc oxide (IZO) layer, and the sputtering deposition time is 10 seconds. The copper-zirconium ratio of the second copper-zirconium (Cu: Zr) layer is copper (Cu): zirconium (Zr) = 80:20, the distance between the target and the substrate is 5 cm, and the sputtering power is 60 watts; An indium zinc oxide (IZO) layer is deposited on the second copper-zirconium (Cu: Zr) layer by radio frequency (RF) magnetron sputtering. The sputtering deposition time is 5 minutes. The distance between the target and the substrate is 5 cm. The sputtering power is 125 watts.

The transparent conductive film of indium zinc oxide / copper zirconium / indium zinc oxide according to the present invention, wherein the target material is an alloy target composed of indium zinc oxide (IZO) ceramic target, zirconium (Zr) metal target, and copper (Cu) sheet. The diameter of the target is 3 inches, and the thickness of the target is 6 mm.

In the transparent conductive film of indium zinc oxide / copper zirconium / indium zinc oxide according to the present invention, the sputtering gas system of the target deposited on the substrate is argon (Ar), and the flow rate of the argon (Ar) is 4.0sccm (gas flow unit), the base pressure of the target sputtering is 5 × 10 ^-5 Torr (torr), and the process pressure of the target sputtering is 3mTorr (torr).

The transparent conductive film of indium zinc oxide / copper zirconium / indium zinc oxide according to the present invention, wherein the substrate is glass, has a sheet resistance of 13.2 Ω / o, a light transmittance of 88%, and a photoelectric index of 1.68E ^-02 Ω ^-1 .

Regarding the technical means adopted by the present invention to achieve the above-mentioned use purpose and effects, the preferred and feasible embodiments are listed, and the drawings are shown in detail as follows:

In the embodiment of the present invention, please refer to the first figure, which mainly deposits the target material on the substrate 1, and the substrate 1 is rotated during the sputtering process, so that the film has sufficient time for heat transfer and improves the The uniformity of the film. The film is a transparent conductive film 2. The transparent conductive film 2 is provided with a first indium zinc oxide (IZO) layer 20 (indium zinc oxide film) and a second copper zirconium (Cu: Zr) layer 21 (Copper zirconium film) and a third indium zinc oxide (IZO) layer 22 (indium zinc oxide film), wherein the first indium zinc oxide (IZO) layer 20 is a radio frequency (RF) magnetron sputtering deposited on the substrate 1. Sputter deposition time is 5 minutes. The distance between the target and the substrate 1 is 5 cm. The sputtering power is 125 watts. The first indium zinc oxide (IZO) layer 20 helps the second copper zirconium ( Cu: Zr) layer 21 is sputter deposited; the second copper-zirconium (Cu: Zr) layer 21 is a direct current (DC) magnetron sputtering deposited on the first indium zinc oxide (IZO) layer 20, and the sputtering deposition time is For 10 seconds, the copper-zirconium ratio of the second copper-zirconium (Cu: Zr) layer 21 is copper (Cu): zirconium (Zr) = 80:20, and the target and the The distance between the plate 1 is 5 cm, and the sputtering power is 60 watts. The third indium zinc oxide (IZO) layer 22 is deposited on the second copper-zirconium (Cu: Zr) layer 21 by radio frequency (RF) magnetron sputtering. The sputtering deposition time is 5 minutes, the distance between the target and the substrate 1 is 5 cm, and the sputtering power is 125 watts. The third indium zinc oxide (IZO) layer 22 contributes to the second copper zirconium (Cu: Zr) layer 21 avoids oxidation; thus, the target material is an alloy target composed of an indium zinc oxide (IZO) ceramic target, a zirconium (Zr) metal target, and a copper (Cu) plate. The diameter of the target material is 3 inches. The thickness of the target material is 6 mm. The sputtering gas system of the target material deposited on the substrate 1 is argon (Ar), and the flow rate of the argon (Ar) is 4.0 sccm (gas flow unit). The bottom pressure of the target sputtering is 5 × 10 ^-5 Torr, and the process pressure of the target sputtering is 3mTorr.

The sputtering equipment used in the present invention is mainly provided with a vacuum cavity, a gas control system, a vacuum pumping system, a vacuum gauge, and a power supply. Among them, the vacuum cavity system has a position where three sets of sputtering targets can be placed. Rotating substrate, two sets of tungsten filament heaters, and one set of rotating gears; the gas control system has three sets of mass flow controllers (MFC) to control the gas (argon, oxygen, and nitrogen) flow; the vacuum Pump system includes oil mechanical pump (ALCATEL 2012A) and high-vacuum oil-type diffusion pump; the vacuum gauge uses a thermocouple vacuum gauge, when the pressure is in a high vacuum, a hot cathode ion vacuum gauge is used; the power supply The device is a set of high frequency radio frequency (RF) power supplies and the other is a direct current (DC) power supply; when sputtering, the vacuum cavity is firstly powered by the oil mechanical pump of the vacuum pump system (ALCATEL 2012A) Pump to rough vacuum, and then use the high-vacuum oil-type diffusion pump of the vacuum pump system to pump to high vacuum to improve the quality of thin film and hydrogen plasma treatment. In addition, UV-visible spectrometer (Hi tachi Ultraviolet-Visible 2008A Spectrophotometer) to measure the average light transmittance (Avg. Transmittance) and photoelectric index (Figure of merit, FOM) of the transparent conductive film 2, such as the formula: The Four-Point Probe can measure the sheet resistance of the transparent conductive film 2 and the Surface Profiler (α-step) can measure the thickness of the transparent conductive film 2 (Thickness ).

The present invention deposits the first indium zinc oxide (IZO) layer 20 and the third indium zinc oxide (IZO) layer 22 by radio frequency (RF) magnetron sputtering. Please refer to the second figure, which is indium oxide. Zinc (IZO) thin film sputtering deposition time Time (min) and thickness Thickness (nm) reference chart, as shown in the second figure, when the sputtering deposition time is 5 minutes (min), the first indium zinc oxide (IZO) The thickness of the layer 20 or the third indium zinc oxide (IZO) layer 22 is about 116 (nm), and when the sputtering deposition time is 20 minutes (min), the first indium zinc oxide (IZO) layer 20 or the first The thickness of the indium zinc oxide (IZO) layer 22 is about 326 (nm). Therefore, as the sputtering deposition time increases from 5 minutes, 10 minutes, and 20 minutes, it undergoes adsorption, diffusion, nucleation, grain growth, and The grains are agglomerated, that is, the first indium zinc oxide (IZO) layer 20 or the third indium zinc oxide (IZO) layer 22 is gradually formed.

The present invention deposits the first indium zinc oxide (IZO) layer 20 and the third indium zinc oxide (IZO) layer 22 by radio frequency (RF) magnetron sputtering. Please refer to the third figure, which is indium oxide The reference graph of the sputter deposition time (min) and sheet resistance (Ω / o) of the zinc (IZO) thin film can be seen from the third graph. When the substrate is glass or plastic (PC), it follows Sputter deposition time increased from 5 minutes, 10 minutes, and 20 minutes, and the change in sheet resistance gradually decreased after decreasing. The reason is that as time increases, particles sputtered have more energy to diffuse during film formation. To the proper position and to reduce the scattering of the grain boundaries, the surface crystallinity of the film is gradually improved, so the sheet resistance value is improved.

The present invention deposits the first indium zinc oxide (IZO) layer 20 and the third indium zinc oxide (IZO) layer 22 by radio frequency (RF) magnetron sputtering. Please refer to the fourth figure, which is a wavelength Wavelength (Nm) and transmittance Tansmittance (% T) reference picture (a), the fourth picture shows that when the substrate is glass (glass), the sputtering deposition time is 5 minutes, 10 minutes, 20 minutes (thickness of about 116 nm to 326 nm), the average light transmittance is at least 79%.

In the present invention, the first indium zinc oxide (IZO) layer 20 and the third indium zinc oxide (IZO) layer 22 are deposited by radio frequency (RF) magnetron sputtering. Please refer to the fifth figure, which is indium oxide. Zinc (IZO) thin film sputter deposition time (min) and light transmittance Tansmittance (% T) reference chart, as shown in the fifth figure, when the substrate is glass (glass), sputter deposition time of 5 minutes, light transmission Rate 79%, photoelectric index 1.38E ^-03 Ω ^-1 ; sputtering deposition time 10 minutes, light transmittance 86%, photoelectric index 1.87E ^-03 Ω ^-1 ; sputtering deposition time 20 minutes, light transmittance 81%, Photoelectric index 1.74E ^-02 Ω ^-1 .

In the present invention, the second copper-zirconium (Cu: Zr) layer 21 is deposited by direct current (DC) magnetron sputtering. Please refer to the sixth and seventh figures. The sixth figure is the wavelength Wavelength (nm) and the light transmittance. Tansmittance (% T) reference picture (2), the seventh picture is the zirconium (Zr) ratio Proportion (%) and light transmittance Tansmittance (% T) reference picture, can be seen from the sixth and seventh pictures, when sputtering The thicknesses of the first indium zinc oxide (IZO) layer 20 and the third indium zinc oxide (IZO) layer 22 are kept constant. The sputtering deposition time is 5 minutes, the sputtering power is 125 watts, and the second The sputter deposition time of the copper-zirconium (Cu: Zr) layer 21 is 20 seconds, and the sputtering power is 60 watts. It can be known that when the copper-zirconium ratio is copper (Cu): zirconium (Zr) = 90: The sheet resistance of 10 is 20.3Ω / o, the light transmittance is 75%, and the photoelectric index is 2.77E ^-03 Ω ^-1 ; when the ratio of copper to zirconium is copper (Cu): zirconium (Zr) = 80: 20, the sheet resistance is 8.5 Ω / o, the light transmittance is 82%, the photoelectric index is 1.62E ^-02 Ω ^-1 ; when the copper-zirconium ratio copper (Cu): zirconium (Zr) = 70:30, the sheet resistance is 56.9Ω / o, and the light transmission The rate is 77%, and the photoelectric index is 1. 29E ^-03 Ω ^-1 ; When the ratio of copper to zirconium is copper (Cu): zirconium (Zr) = 50:50, the sheet resistance is 111Ω / o, the light transmittance is 62%, and the photoelectric index is 7.56E ^-05 Ω ^-1 ; Therefore, the addition of zirconium (Zr) can protect copper (Cu) from being oxidized, and the light transmittance is improved; the total film thickness of copper (Cu): zirconium (Zr) = 90: 10 is 96.1nm, The total film thickness of copper (Cu): zirconium (Zr) = 80:20 is 88.43 nm, the total film thickness of copper (Cu): zirconium (Zr) = 70:30 is 96.27 nm, and the copper (Cu): zirconium (Zr) ) = 50: 50 The total film thickness is 113.3 nm. It can be seen that as the area occupied by zirconium (Zr) increases, the growth rate also increases. However, due to the addition of excessive area ratio zirconium (Zr), the metal layer film The thickness will increase. As the metal content of zirconium (Zr) increases, the light reflection of zirconium (Zr) will be higher than that of copper (Cu), so that the light transmittance will be relatively reduced.

In the present invention, the second copper-zirconium (Cu: Zr) layer 21 is deposited by direct current (DC) magnetron sputtering. Please refer to FIG. 8, which is a copper-zirconium (Cu: Zr) thin-film sputtering deposition Time (sec) and sheet resistance (Ω / o) reference chart, as can be seen from the eighth figure, when the second copper-zirconium (Cu: Zr) layer 21 has a copper-zirconium ratio copper (Cu): zirconium (Cu) Zr) = 80: 20. When the substrate is glass or plastic (PC), it means that the copper-zirconium (Cu: Zr) film sputter deposition time increases, and the sheet resistance decreases accordingly. See also ninth and tenth. As shown in the figure, the ninth figure is the reference figure (C) of the wavelength Wavelength (nm) and the light transmittance Tansmittance (% T), and the tenth figure is the sputter deposition time (sec) of the copper-zirconium (Cu: Zr) film. With reference to the transmittance Tansmittance (% T), it can be known from the eighth to tenth graphs that when the copper-zirconium ratio of the second copper-zirconium (Cu: Zr) layer 21 is copper (Cu): zirconium (Zr) = 80 : 20, the thicknesses of the first indium zinc oxide (IZO) layer 20 and the third indium zinc oxide (IZO) layer 22 are sputter-deposited, and the thickness of the sputter deposition is 5 minutes. Zr: sputtering (Cu Zr) layer 21 is deposited plating time of 10 seconds, a sheet resistance of 13.2Ω / o, the light transmittance was 88%, the photoelectric indicators 1.68E ^-02 Ω ^-1; if the second copper zirconium The sputter deposition time of the (Cu: Zr) layer 21 is 20 seconds, the sheet resistance is 8.5Ω / o, the light transmittance is 83%, and the photoelectric index is 1.62E ^-02 Ω ^-1 ; if the second copper zirconium ( The sputter deposition time of the Cu: Zr) layer 21 is 30 seconds, the sheet resistance is 5.7 Ω / o, the light transmittance is 64%, and the photoelectric index is 2.02E ^-03 Ω ^-1 ; if the second copper zirconium (Cu : Zr) The sputter deposition time of the layer 21 is 50 seconds, the sheet resistance is 3.35Ω / o, the light transmittance is 47%, and the photoelectric index is 1.57E ^-04 Ω ^-1 ; therefore, it can be known that the second copper The zirconium (Cu: Zr) layer 21 has a different sputtering deposition time, and its light transmittance is more than 47%. However, as the thickness of the second copper zirconium (Cu: Zr) layer 21 increases, the light transmittance also increases. With the decline; therefore, when the sheet resistance is 13.2 Ω / o, the light transmittance is 88%, and the photoelectric index is 1.68E ^-02 Ω ^-1 , which can achieve the best corrosion resistance, conductivity and light transmission.

In summary, the embodiments of the present invention have indeed achieved the intended purpose and use effect, and have not seen the same structural features as known and common antecedents. Therefore, the present invention should be able to meet the application requirements of the invention patent, and proposed according to law The application is urged to be concluded as soon as possible, and the patent is granted.

1‧‧‧ substrate

2‧‧‧ transparent conductive film

20‧‧‧ the first indium zinc oxide (IZO) layer

21‧‧‧Second copper-zirconium (Cu: Zr) layer

22‧‧‧ third indium zinc oxide (IZO) layer

The first figure is a schematic diagram of a transparent conductive film on a substrate according to an embodiment of the present invention. The second figure is a reference diagram of the sputtering time and thickness of the indium zinc oxide thin film according to the embodiment of the present invention. The third figure is a reference diagram of sputtering time and sheet resistance of the indium zinc oxide thin film according to the embodiment of the present invention. The fourth figure is a reference chart (1) of wavelength and light transmittance according to the embodiment of the present invention. The fifth figure is a reference diagram of the sputtering time and transmittance of the indium zinc oxide thin film according to the embodiment of the present invention. The sixth diagram is a reference diagram (2) of the wavelength and light transmittance of the embodiment of the present invention. The seventh figure is a reference chart of zirconium ratio and light transmittance according to the embodiment of the present invention. The eighth figure is a reference diagram of the sputter deposition time and sheet resistance of a copper-zirconium thin film according to an embodiment of the present invention. The ninth figure is a reference chart (three) of the wavelength and light transmittance of the embodiment of the present invention. The tenth figure is a reference diagram of the sputter deposition time and light transmittance of a copper-zirconium thin film according to an embodiment of the present invention.

Claims (4)

A transparent conductive film of indium zinc oxide / copper zirconium / indium zinc oxide is mainly deposited on a substrate by sputtering, and the substrate is rotated during the sputtering process, so that the film has sufficient time for heat transfer and improves the uniformity of the film. The characteristic is that the first indium zinc oxide (IZO) layer is deposited on the substrate by radio frequency (RF) magnetron sputtering. The sputtering deposition time is 5 minutes, and the distance between the target and the substrate is 5 cm. The sputtering power is 125 watts. The second copper-zirconium (Cu: Zr) layer is a direct current (DC) magnetron sputtering deposited on the first indium zinc oxide (IZO) layer. The sputtering deposition time is 10 seconds. The copper-zirconium ratio of the second copper-zirconium (Cu: Zr) layer is copper (Cu): zirconium (Zr) = 80: 20, the distance between the target and the substrate is 5 cm, and the sputtering power is 60 watts; An indium zinc oxide (IZO) layer is deposited on the second copper-zirconium (Cu: Zr) layer by radio frequency (RF) magnetron sputtering. The sputtering deposition time is 5 minutes. The distance between the target and the substrate is 5 cm. The sputtering power is 125 watts. The transparent conductive film of indium zinc oxide / copper zirconium / indium zinc oxide according to item 1 of the scope of application for patent, wherein the target material is an indium zinc oxide (IZO) ceramic target, a zirconium (Zr) metal target, and a copper ( Cu) sheet alloy target, the target diameter is 3 inches, and the target thickness is 6 mm. The transparent conductive film of indium zinc oxide / copper zirconium / indium zinc oxide according to item 1 of the scope of the patent application, wherein the sputtering gas system of the target sputtering deposition on the substrate is argon (Ar), and the argon The flow rate of gas (Ar) is 4.0 sccm (gas flow unit), the bottom pressure of the target sputtering is 5 × 10 ^-5 Torr (torr), and the process pressure of the target sputtering is 3 mTorr (torr). . The transparent conductive film of indium zinc oxide / copper zirconium / indium zinc oxide according to item 1 of the scope of the patent application, wherein the substrate is glass, and the transparent conductive film formed on the substrate has a sheet resistance of 13.2 Ω / □, The light transmittance is 88%, and the photoelectric index is 1.68E ^-02 Ω ^-1 .