A low oxygen content alloy target and preparation method thereof

Abstract

The present invention relates to the technical field of alloy target materials, and provides a low-oxygen content alloy target material and a preparation method thereof, comprising: preparing alloy powder; uniformly mixing the alloy powder and a binder to form a mixture; placing the mixture in a mold for warm isostatic pressing to form a blank; performing catalytic degreasing treatment on the blank to form a preform; and vacuum sintering the preform to obtain a low-oxygen content alloy target material. The preparation method of the low-oxygen content alloy target material provided by the present invention is to form a blank by performing warm isostatic pressing on a mixture of alloy powder and a binder, and then perform catalytic treatment on the blank to crack and remove the binder in the blank, thereby avoiding oxidation of metal elements caused by high-temperature degreasing, and obtaining a preform with a low oxygen content. Finally, the preform with a low oxygen content is vacuum sintered, which can not only form an alloy target with a low oxygen content, but also reduce the formation of pores, thereby improving the density and conductivity of the finished target material.

Description

Technical Field

[0001] The invention belongs to the technical field of alloy target materials, and in particular relates to a low-oxygen content alloy target material and a preparation method thereof. Background Art

[0002] For the target material, the purity and density of the target material have a critical impact on the coating performance of the target material. The purity of the target material will directly affect the uniformity and stability of the coating, as well as the degree of poisoning of the target surface during sputtering, thereby affecting the service life of the target material. In addition to the requirements for the content of cationic impurity elements, high-purity alloy targets also have requirements for the content of elements such as C, N, O, and S. Oxygen, as a common impurity element, will affect the performance and quality of alloy targets. In the process of preparing alloy targets by powder metallurgy, especially in the molding process, oxidizing substances will be introduced, causing the oxygen content in the alloy target to exceed the standard. At present, there are two main methods commonly used to control the oxygen content of alloys. One is to select high-purity raw materials with ultra-low oxygen content, and the other is to add specific alloy elements to absorb oxygen during the manufacturing process. However, the selection of high-purity raw materials with ultra-low oxygen content can only be guaranteed in the raw material link, but oxygen will still be introduced in the manufacturing link. By adding specific alloy elements to absorb oxygen, these elements will cause impurities to form. Therefore, how to control the low oxygen content of alloy targets in the manufacturing link is very critical.

[0003] The performance of the green billet directly affects the performance of the final product. Therefore, when manufacturing alloy targets by powder metallurgy, in order to achieve good molding, auxiliary metal powder fills the mold, and molds a high-density, uniform, and high-strength green billet, it is usually necessary to add common binders such as polyvinyl alcohol (PVA), polyethylene glycol (PEG), paraffin, and cellulose to the powder. However, the addition of the above common binders to the green billet requires treatment in high-temperature air at 500 to 600°C to burn and eliminate them. In this process, the metal powder will be oxidized, resulting in an increase in oxygen content.

[0004] Therefore, it is necessary to develop a method for preparing a low-oxygen content alloy target. Summary of the invention

[0005] The object of the present invention is to provide a low-oxygen content alloy target material and a preparation method thereof, aiming to solve the problem that the alloy target material prepared by the existing preparation method of the alloy target material has a high oxygen content.

[0006] To achieve the above objectives, the present invention adopts the following technical solutions:

[0007] In a first aspect, the present invention provides a method for preparing a low-oxygen content alloy target, comprising the following steps:

[0008] preparing alloy powder;

[0009] The alloy powder and the binder are mixed evenly to form a mixture;

[0010] Placing the mixed material in a mold for warm isostatic pressing to form a green billet;

[0011] The green blank is subjected to catalytic degreasing treatment to form a preform;

[0012] The preform is vacuum sintered to obtain an alloy target material with low oxygen content.

[0013] In a second aspect, the present invention provides a low-oxygen content alloy target, which is prepared by the method for preparing a low-oxygen content alloy target provided by the present invention, and the oxygen content of the alloy target is lower than 100 ppm.

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] If the oxygen content of the copper gallium or copper indium gallium target material preform is high before vacuum sintering, pores are easily generated during the vacuum sintering stage, which will affect the density and strength of the target material. It takes a very high temperature to reduce the oxidized copper gallium or copper indium gallium in the target material preform to remove oxygen, which is very difficult to operate in practice, thereby affecting the conductivity of the alloy target material. Therefore, the preparation method of the low-oxygen content alloy target material provided by the first aspect of the present invention is to first mix the alloy powder and the binder, and then dissolve the binder in the mixture by warm isostatic pressing to produce viscosity, so that the alloy powder (CuGa or CuInGa) without plasticity or viscosity is formed into a blank, and then the blank is subjected to catalytic degreasing treatment to crack and remove the binder, so that high-temperature degreasing is not required, and oxidation of metal elements caused by high temperature can be avoided. Therefore, the preparation method of the present invention can form a target material preform with a low oxygen content, and finally the preform with a low oxygen content is vacuum sintered, which can not only form an alloy target material with a low oxygen content and give the alloy target material good conductivity, but also reduce pore formation and improve the density and strength of the target material finished product. Therefore, the alloy target material prepared by the preparation method of the present invention not only has low oxygen content and good electrical conductivity, but also has good density and high strength.

[0016] The low-oxygen content alloy target material provided in the second aspect of the present invention is prepared by the preparation method of the low-oxygen content alloy target material provided by the present invention, and the oxygen content of the alloy target material is lower than 100ppm. Therefore, the alloy target material of the present invention has good density, high strength and good conductivity, and therefore has the advantages of high coating film forming rate, good thin film uniformity, and long target material service life. DETAILED DESCRIPTION

[0017] 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.

[0018] The terms used in the embodiments of the present invention are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. The singular forms "a", "said" and "the" used in the embodiments of the present invention and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings.

[0019] The weight of the relevant components mentioned in the description of the embodiments of the present invention may not only refer to the specific content of each component, but also indicate the weight ratio between the components. Therefore, as long as the content of the relevant components is proportionally enlarged or reduced according to the description of the embodiments of the present invention, it is within the scope disclosed in the description of the embodiments of the present invention. Specifically, the mass described in the description of the embodiments of the present invention may be a mass unit known in the chemical industry such as μg, mg, g, kg, etc.

[0020] Plasma spraying, melting and pouring, hot pressing, hot isostatic pressing, vacuum sintering and other processes are commonly used in the manufacture of alloy targets. For alloy targets (such as CuGa, CuInGa, etc.), plasma spraying and melting and pouring are easy to cause the target to be oxidized; hot pressing or hot isostatic pressing is difficult to manufacture long large-sized rotating targets; and when vacuum sintering is used to manufacture long large-sized rotating targets, it is necessary to first add a binder to form a high-strength billet, then remove the binder at high temperature, and finally vacuum sinter to form the target. However, removing the binder at high temperature (500-600°C) will cause the metal elements (such as Cu, In, Ga, etc.) of the billet to oxidize, resulting in a high oxygen content in the billet. Billets with high oxygen content are prone to pores during the vacuum sintering stage, affecting the density and strength of the target, and it is difficult to burn out the oxygen in the billet, resulting in a high oxygen content in the alloy target and poor conductivity.

[0021] An embodiment of the present invention provides a method for preparing a low-oxygen content alloy target, comprising the following steps:

[0022] S01: preparing alloy powder;

[0023] S02: uniformly mixing the alloy powder and the binder to form a mixture;

[0024] S03: placing the mixed material in a mold for warm isostatic pressing to form a green billet;

[0025] S04: performing catalytic degreasing treatment on the green billet to form a preform;

[0026] S05: vacuum sintering the preform to obtain a low-oxygen content alloy target.

[0027] If the oxygen content of the copper gallium or copper indium gallium target material preform is high before vacuum sintering, pores are easily generated during the vacuum sintering stage, which will affect the density and strength of the target material. It takes a very high temperature to reduce the oxidized copper gallium or copper indium gallium in the target material preform to remove oxygen, which is very difficult to operate in practice, thereby affecting the conductivity of the alloy target material. Therefore, the preparation method of the low-oxygen content alloy target material provided by the embodiment of the present invention is to first mix the alloy powder and the binder, and then dissolve the binder in the mixture by warm isostatic pressing to produce viscosity, so that the alloy powder (CuGa or CuInGa) without plasticity or viscosity is formed into a blank, and then the blank is subjected to catalytic degreasing treatment to crack and remove the binder, so that high-temperature degreasing is not required, and oxidation of metal elements caused by high temperature can be avoided. Therefore, the preparation method of the present invention can form a target material preform with a low oxygen content, and finally the preform with a low oxygen content is vacuum sintered, which can not only form an alloy target material with a low oxygen content, but also give the alloy target material good conductivity, and reduce pore formation, thereby improving the density and strength of the target material finished product. Therefore, the alloy target material prepared by the preparation method of the present invention not only has low oxygen content and good electrical conductivity, but also has good density and high strength.

[0028] In the above step S01, the step of preparing the alloy powder may include: putting various metal sources into a smelting furnace according to a certain ratio, smelting in a vacuum or inert atmosphere at 600-1200°C to obtain an alloy melt; and forming the alloy melt into alloy powder by gas atomization. The oxygen content of the metal source is less than 50ppm, and specifically may include copper, indium, gallium blocks, etc., with an oxygen content of less than 50ppm.

[0029] In an embodiment, the step of uniformly mixing the alloy powder and the binder may include: the step of uniformly mixing the alloy powder and the binder includes: placing the alloy powder and the binder under vacuum or an inert atmosphere, first performing a low-speed stirring treatment, then starting to heat up to the target temperature, and switching to a high-speed shearing treatment when the temperature reaches a preset temperature, and finally cooling down from the target temperature, and switching to a low-speed stirring treatment when the temperature drops to a preset temperature, until the stirring is stopped when the temperature drops below 30°C, to obtain a mixture. In an embodiment of the present invention, the alloy powder and the binder are placed under a vacuum or an inert atmosphere, first subjected to a low-speed stirring treatment, then heated to dissolve the binder to generate viscosity, and subjected to a high-speed shearing treatment, which can prevent the binder from agglomerating, and is conducive to the binder and the alloy powder being fully mixed and uniformly mixed, and finally the binder is solidified by cooling and stirring at a low speed to form particles of the alloy powder coated with the binder, which can effectively prevent the oxidation of the alloy powder, help to form an alloy target with a low oxygen content, and can solve the problem of a small amount of binder that is difficult to mix uniformly.

[0030] In a specific embodiment, the step of uniformly mixing the alloy powder and the binder may include: evacuating the power mixing device to a slightly negative pressure, then introducing N2 to normal pressure, then adding the alloy powder and the binder to the power mixing device, and introducing and discharging N2 for a period of time, stopping discharging N2 and continuing to introduce N2 to maintain normal pressure; stirring at a low speed for 10 to 30 minutes under the conditions of a dispersion speed of 500 to 1500 rpm, a revolution speed of 5 to 15 rpm, and a rotation speed of 20 to 40 rpm, and then heating at a rate of 3 to 5 ° C / min. When the temperature rises to 140-150°C, adjust the dispersion speed to 2500-4000rpm, the revolution speed to 30-40rpm, and the rotation speed to 70-90rpm, and continue to heat up to 200-250°C. After high-speed shearing for 20-60min, cool at a rate of 3-5°C / min. When the temperature drops to 150°C, adjust the dispersion speed to 500-1500rpm, the revolution speed to 5-15rpm, and the rotation speed to 5-15rpm for low-speed stirring. Stop stirring when the temperature drops to 20-30°C to obtain a mixture. The embodiment of the present invention first mixes by stirring at a low speed, then heats up to dissolve the binder to generate viscosity and performs high-speed shearing, which can prevent the binder from agglomerating, and is conducive to fully and evenly mixing the binder and the alloy powder. Finally, the binder is solidified by cooling and stirring at a low speed to form particles of the alloy powder coated with the binder, which can effectively prevent the oxidation of the alloy powder, help to form an alloy target with a low oxygen content, and can solve the problem of a small amount of binder that is difficult to mix evenly.

[0031] In an embodiment, the alloy powder composition includes copper and gallium, and the mass ratio of copper to gallium can be but not limited to (20-90) / (10-80). Specifically, the copper block and the gallium block can be put into a smelting furnace according to the mass ratio of the copper block to the gallium block of 90 / 10, 60 / 40, 20 / 80, etc., and smelted in a vacuum or inert atmosphere at 600-1200°C to obtain a copper-gallium alloy melt, and the copper-gallium alloy melt is formed into a copper-gallium alloy powder by gas atomization.

[0032] In an embodiment, the alloy powder composition includes copper, indium and gallium, and the mass ratio of copper, indium and gallium can be but not limited to (20-90) / (5-30) / (5-50). Specifically, the copper block, indium block and gallium block can be put into a melting furnace according to the mass ratio of copper block, indium block and gallium block of 90 / 5 / 5, 60 / 10 / 30, 20 / 30 / 50, etc., and are smelted in vacuum or inert atmosphere at 600-1200°C to obtain a copper indium gallium alloy melt, and the copper indium gallium alloy melt is formed into a copper indium gallium alloy powder by gas atomization.

[0033] In the above step S02, the binder is polyoxymethylene. The mass ratio of the alloy powder to the binder is 100 / (0.5-1.5), preferably 100 / (0.3-0.8), more preferably 100 / (0.3-0.6), and even more preferably 100 / (0.3-0.4).

[0034] In the above step S03, the mold is a flexible resin mold. Specifically, the flexible resin mold can be a mold made of polyurethane, natural rubber, silicone, etc. These molds are conducive to high-pressure deformation of the mixed powder to form a blank.

[0035] In some embodiments, the temperature of warm isostatic pressing is 150-200° C. and the pressure is 100-300 MPa. The temperature range of warm isostatic pressing can dissolve the binder in the mixture to generate viscosity, and bond the alloy powder (CuGa alloy powder or CuInGa alloy powder) without plasticity or viscosity to form a green billet.

[0036] In the above step S04, the step of subjecting the green billet to catalytic degreasing treatment includes: heating the green billet to 100-150° C. in an inert atmosphere, and then introducing an acid to crack and remove the binder in the green billet; wherein the acid is nitric acid or oxalic acid.

[0037] Specifically, the binder is polyoxymethylene (POM), and the acid is used as a catalyst. A metering pump is used to extract the acid and inject it into the furnace. The polyoxymethylene in the blank will be quickly decomposed into formaldehyde gas in an acidic atmosphere of 100-150°C, so that the polyoxymethylene is removed from the blank, so that high-temperature degreasing is not required, and the oxidation of metal elements caused by high temperature is avoided. Compared with the traditional method of removing the binder by high-temperature calcination in air, the oxygen content of the preform can be effectively reduced, and the pores generated by the subsequent vacuum sintering of the preform with low oxygen content can be reduced, thereby improving the density and strength of the finished target material, and reducing the oxygen content of the final alloy target material, thereby improving the conductivity of the target material. The cracking equation is as follows:

[0038] (CH2O)n(acidic solution) → nCH2O

[0039] The gases generated by formaldehyde gas after combustion are CO, CO2 and H2O. These gases are then heated by the exhaust gas processor to convert CO into CO2 and discharge it. The discharged gas does not pollute the atmosphere at all, achieving green emissions.

[0040] In some embodiments, the flow rate of the acid is 1.0 to 5.0 g / min, and can further be 4.0 to 5.0 g / min; the time for cracking and removal is 1 to 5 hours, and can further be 1.5 to 2.5 hours. When oxalic acid is selected as the acid, the concentration of oxalic acid can be selected to be 10 to 20%. When nitric acid is selected as the acid, the concentration of nitric acid can be selected to be 70 to 98%.

[0041] In the above step S04, the vacuum sintering temperature is 500-800°C, and can be further 600-700°C, and the vacuum degree is 10 -2 ~10 -3 Pa.

[0042] An embodiment of the present invention provides an alloy target material with low oxygen content, which is prepared by the method for preparing an alloy target material with low oxygen content provided by the present invention, and the oxygen content of the alloy target material is lower than 100 ppm.

[0043] The low-oxygen content alloy target material provided in the embodiment of the present invention is prepared by the preparation method of the low-oxygen content alloy target material provided by the present invention, and the oxygen content of the alloy target material is lower than 100 ppm. Therefore, the alloy target material of the present invention has good density, high strength and good conductivity, and therefore has the advantages of high coating film forming rate, good thin film uniformity, and long target material service life.

[0044] The following describes the invention in conjunction with specific embodiments.

[0045] Example 1

[0046] This embodiment provides a method for preparing a CuGa alloy target with a low oxygen content, comprising the following steps:

[0047] S11: putting a Cu block and a Ga block into a melting furnace at a mass ratio of 7 / 3, melting them at 1050° C. in an inert atmosphere to obtain a CuGa alloy melt, and forming a CuGa alloy powder from the CuGa alloy melt by gas atomization, wherein the oxygen content of the Cu block and the Ga block is less than 50 ppm;

[0048] S12: evacuate the power mixing device to a slight negative pressure, then introduce N2 to normal pressure, and then add CuGa alloy powder and polyoxymethylene into the power mixing device according to the mass ratio of CuGa alloy powder and polyoxymethylene being 100 / 0.3, and introduce and discharge N2 at the same time for a period of time, stop discharging N2 and continue to introduce N2 to maintain normal pressure; stir at a low speed for 20 minutes under the conditions of a dispersion speed of 1000rpm, a revolution speed of 10rpm, and a rotation speed of 30rpm, and then heat at a rate of 5°C / min. When the temperature is increased to 150°C, adjust the dispersion speed to 3000rpm, the revolution speed to 30rpm, and the rotation speed to 80rpm, and continue to heat to 200°C, high-speed shear for 30 minutes, and then cool at a rate of 5°C / min. When the temperature is reduced to 150°C, adjust the dispersion speed to 1000rpm, the revolution speed to 10rpm, and the rotation speed to 30rpm for low-speed stirring, until the temperature is reduced to room temperature, stop stirring, and obtain a mixture;

[0049] S13: placing the mixed material in a polyurethane mold, and performing warm isostatic pressing at 180° C. and 200 MPa to form a green blank;

[0050] S14: placing the green billet in a furnace with a nitrogen atmosphere and heating it to 130° C., then introducing oxalic acid at a flow rate of 4.0 g / min for 2.5 hours to decompose the polyoxymethylene in the green billet into formaldehyde gas and separate it from the green billet, thereby obtaining a preform;

[0051] S15: Place the preform in a vacuum of 10 -3 Pa, vacuum sintering was carried out at 650°C for 6 hours to obtain a CuGa alloy target with low oxygen content.

[0052] Example 2

[0053] This embodiment provides a method for preparing a CuGa alloy target with a low oxygen content. The preparation steps are different from those in Embodiment 1, except that in step S14, the target is heated to 100° C., and then oxalic acid is introduced at a flow rate of 4.5 g / min for 2 h.

[0054] Example 3

[0055] This embodiment provides a method for preparing a CuGa alloy target with a low oxygen content. The preparation steps are different from those in Embodiment 1, except that in step S14, the target is heated to 140° C., and then oxalic acid is introduced at a flow rate of 5 g / min for 1.5 h.

[0056] Example 4

[0057] This embodiment provides a method for preparing a CuGa alloy target with a low oxygen content. The preparation steps are different from those of Embodiment 1, except that nitric acid is introduced in step S14.

[0058] Example 5

[0059] A method for preparing a low-oxygen content CuInGa alloy target comprises the following steps:

[0060] S51: putting a Cu block, an In block and a Ga block into a melting furnace at a mass ratio of 7 / 1 / 2, melting them at 1050° C. in an inert atmosphere to obtain a CuInGa alloy melt, and forming a CuInGa alloy powder from the CuInGa alloy melt by gas atomization;

[0061] S52: evacuate the power mixing device to a slight negative pressure, then introduce N2 to normal pressure, and then add CuInGa alloy powder and polyoxymethylene into the heating device according to the mass ratio of CuInGa alloy powder and polyoxymethylene being 100 / 0.8, and introduce and discharge N2 at the same time for a period of time, stop discharging N2 and continue to introduce N2 to maintain normal pressure; stir at a low speed for 20 minutes under the conditions of a dispersion speed of 1000rpm, a revolution speed of 10rpm, and a rotation speed of 30rpm, and then heat at a rate of 5°C / min. When the temperature is increased to 150°C, adjust the dispersion speed to 3000rpm, the revolution speed to 30rpm, and the rotation speed to 80rpm, and continue to heat to 200°C, high-speed shear for 30 minutes, and then cool at a rate of 5°C / min. When the temperature is reduced to 150°C, adjust the dispersion speed to 1000rpm, the revolution speed to 10rpm, and the rotation speed to 30rpm for low-speed stirring, until the temperature is reduced to room temperature, stop stirring, and obtain a mixture;

[0062] S53: placing the mixed material in a polyurethane mold, and performing warm isostatic pressing at 180° C. and 200 MPa to form a green blank;

[0063] S54: placing the green billet in a furnace with a nitrogen atmosphere and heating it to 130° C., then introducing oxalic acid at a flow rate of 5.0 g / min for 2.5 hours to decompose the polyoxymethylene in the green billet into formaldehyde gas and separate it from the green billet, thereby obtaining a preform;

[0064] S55: Place the preform in a vacuum of 10 -3 Pa, vacuum sintering was carried out at 650°C for 6 hours to obtain a CuInGa alloy target with low oxygen content.

[0065] Example 6

[0066] A method for preparing a CuInGa alloy target with a low oxygen content, wherein the preparation steps are the same as those of Example 5, except that in step S52, the mass ratio is 100 / 0.5, and in step S54, oxalic acid is introduced at a flow rate of 4.5 g / min for 2 h.

[0067] Comparative Example 1

[0068] A method for preparing a CuGa alloy target comprises the following steps:

[0069] S1: Cu blocks and Ga blocks are mixed in a mass ratio of 7 / 3 to form a CuGa mixture, the CuGa mixture is placed in an alumina crucible, and the smelting chamber is evacuated to 3×10 -2Pa, fill the furnace with argon to wash it, evacuate it again, and then backfill it with argon to make the furnace pressure 0.08MPa. Heat the CuGa mixture at 600℃ for 20min, then raise the temperature to 1050℃. After the CuGa mixture is completely melted, refine it at 950℃ for 3min to obtain a CuGa melt.

[0070] S2: preheating the graphite mold and alumina funnel in an oven at 300°C for 1 h, casting the CuGa melt into the graphite mold, and then naturally cooling to room temperature, demolding, and obtaining an ingot;

[0071] S3: Cut and grind the ingot to obtain a CuGa alloy target.

[0072] Comparative Example 2

[0073] A method for preparing a CuGa alloy target comprises the following steps:

[0074] S1: putting a Cu block and a Ga block into a melting furnace at a mass ratio of 7 / 3, melting them at 1050° C. in an inert atmosphere to obtain a CuGa alloy melt, and forming a CuGa alloy powder from the CuGa alloy melt by gas atomization, wherein the oxygen content of the Cu block and the Ga block is less than 50 ppm;

[0075] S2: Put the CuGa alloy powder into the graphite mold and level it;

[0076] S3: Put the powder into a vacuum hot press furnace and cold pre-press the powder under a pressure of 8Mpa; evacuate the hot press furnace, turn on the heating when the vacuum reaches 0.1pa, raise the temperature to 650℃ at 4℃ / min, keep it warm for 1.5h, then pressurize it at 650℃ with a pressure of 55Mpa, keep it for 2h, then remove the pressurized pressure, naturally reduce the pressure at 650℃ for 1h, and finally cool it under natural pressure reduction. When the temperature drops to 250℃, start to reduce the pressure. After the pressure drops to 10MPa, cool it naturally to below 35℃;

[0077] S3: After demolding, mechanical processing is performed to obtain a CuGa alloy target.

[0078] Comparative Example 3

[0079] A method for preparing a CuGa alloy target comprises the following steps:

[0080] S1: putting a metal Cu block and a Ga block into a melting furnace at a mass ratio of 7 / 3, melting them at 1050° C. in an inert atmosphere to obtain a CuGa alloy melt, and forming a CuGa alloy powder from the CuGa alloy melt by gas atomization;

[0081] S2: The power mixing device is evacuated to a slight negative pressure, and then N2 is introduced to normal pressure, and then the CuGa alloy powder and polyvinyl alcohol are added to the power mixing device according to the mass ratio of CuGa alloy powder to polyvinyl alcohol of 100 / 0.5, and N2 is introduced and discharged for a period of time, then the discharge of N2 is stopped and N2 is continued to be introduced to maintain normal pressure; low-speed stirring is carried out for 20 minutes under the conditions of a dispersion speed of 1000rpm, a revolution speed of 10rpm, and a rotation speed of 30rpm, and then the temperature is increased at a rate of 5°C / min. When the temperature is increased to 150°C, the dispersion speed is adjusted to 3000rpm, the revolution speed is adjusted to 30rpm, the rotation speed is adjusted to 80rpm, and the temperature is continued to be increased to 200°C. After high-speed shearing for 30 minutes, the temperature is reduced at a rate of 5°C / min. When the temperature is reduced to 150°C, the dispersion speed is adjusted to 1000rpm, the revolution speed is adjusted to 10rpm, and the rotation speed is adjusted to 30rpm for low-speed stirring, until the temperature is reduced to room temperature, the stirring is stopped to obtain a mixture;

[0082] S3: placing the mixed material in a polyurethane mold and performing cold isostatic pressing at 200 MPa to form a green blank;

[0083] S4: placing the green body in a nitrogen atmosphere at a temperature of 550° C. for degreasing for 24 hours to burn and remove the polyvinyl alcohol in the green body to obtain a preform;

[0084] S5: Place the preform in a vacuum of 10 -3 Pa, vacuum sintering was carried out at 650°C for 6 hours to obtain a CuGa alloy target with low oxygen content.

[0085] The purity, relative density, oxygen content and resistivity of the alloy targets prepared in Examples 1 to 5 and Comparative Examples 1 to 3 were tested. The test results are shown in Table 1.

[0086] Table 1

[0087]

[0088] It can be seen from Table 1 that the alloy targets prepared in Examples 1 to 6 of the present invention have no cracks, but the alloy target prepared in Comparative Example 1 has microcracks, indicating that the casting method used in Comparative Example 1 is not suitable for preparing alloy targets. The oxygen content and resistivity of the alloy targets prepared in Examples 1 to 6 of the present invention are significantly lower than those of the alloy targets prepared in Comparative Examples 1 to 3, and the density and purity of the alloy targets prepared in Examples 1 to 6 of the present invention are significantly greater than those of the alloy targets prepared in Comparative Examples 1 to 3, indicating that the embodiments of the present invention mix the alloy powder and the binder, and then dissolve the binder in the mixture through warm isostatic pressing to generate viscosity, and bond the CuGa or CuInGa alloy powder without plasticity or viscosity to form a blank, and then catalytically treat the blank to crack and remove the binder, thereby avoiding oxidation of Cu, In, and Ga metal elements caused by high-temperature degreasing, thereby forming a preform with a low oxygen content, and finally vacuum sintering the preform with a low oxygen content, not only can an alloy target with a low oxygen content be formed, but also the formation of pores can be effectively reduced, thereby improving the density and strength of the alloy target.

[0089] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the coating should be included in the protection scope of the present invention.

Claims

1. A method for preparing a low-oxygen content alloy target, characterized in that: The steps include: preparing alloy powder; the alloy powder comprises copper and gallium with an oxygen content of less than 50 ppm; The dynamic mixing device is evacuated to a slight negative pressure, and then N2 is introduced to normal pressure. The alloy powder and binder are then added to the dynamic mixing device. After N2 is introduced and discharged for a period of time, the discharge of N2 is stopped and N2 is continued to be introduced to maintain normal pressure. The low-speed stirring is carried out for 10 to 30 minutes under the conditions of a dispersion speed of 500 to 1500 rpm, a revolution speed of 5 to 15 rpm, and a rotation speed of 20 to 40 rpm. Then the temperature is increased at a rate of 3 to 5 ° C / min. When the temperature is increased to 140 to 150 ° C, the temperature is adjusted. The dispersion speed is 2500-4000rpm, the revolution speed is 30-40rpm, the rotation speed is 70-90rpm, and the temperature is continuously raised to 200-250°C. After high-speed shearing for 20-60min, the temperature is lowered at a rate of 3-5°C / min. When the temperature is lowered to 150°C, the dispersion speed is adjusted to 500-1500rpm, the revolution speed is 5-15rpm, and the rotation speed is 5-15rpm for low-speed stirring. The stirring is stopped when the temperature is lowered to 20-30°C to form a mixture. Placing the mixed material in a mold for warm isostatic pressing to form a green billet; The green blank is subjected to catalytic degreasing treatment to form a preform; The preform is subjected to vacuum sintering to obtain a low-oxygen content alloy target; Wherein, the mass ratio of the alloy powder to the binder is 100 / (0.5-1.5); The binder is polyoxymethylene; The temperature of the warm isostatic pressing is 150-200°C and the pressure is 100-300MPa; The oxygen content of the alloy target is less than 100 ppm.

2. The preparation method according to claim 1, characterized in that: The step of catalytically degreasing the green billet comprises: heating the green billet to 100-150° C. in an inert atmosphere, and then introducing an acid to crack and remove the binder in the green billet; wherein the acid is nitric acid or oxalic acid.

3. The preparation method according to claim 2, characterized in that: The flow rate of the acid is 1.0 to 5.0 g / min; The time for the cleavage removal is 1 to 5 hours.

4. The preparation method according to claim 2, characterized in that: The vacuum sintering temperature is 500-800°C and the vacuum degree is 10 -2 ~10 -3 Pa.

5. The preparation method according to any one of claims 1 to 4, characterized in that: The alloy powder contains copper, indium and gallium.

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