Aluminum neodymium zinc alloy target material for magnetron sputtering and manufacturing method

Abstract

The preparation method comprises the following steps: by taking an aluminum-neodymium intermediate alloy, high-purity aluminum and high-purity zinc in a specific proportion as raw materials, melting, refining and casting the raw materials in a vacuum melting furnace to obtain an aluminum-neodymium-zinc alloy cast ingot, performing homogenizing annealing treatment on the aluminum-neodymium-zinc alloy cast ingot, rolling the aluminum-neodymium-zinc alloy cast ingot, and performing annealing treatment and machining on the aluminum-neodymium-zinc alloy cast ingot after rolling to obtain the aluminum-neodymium-zinc alloy target for magnetron sputtering. And the aluminum-neodymium-zinc target material with the specified size is obtained. The performance of the finally obtained aluminum-neodymium-zinc alloy target material is superior to that of an aluminum-neodymium alloy target material, and the aluminum-neodymium-zinc alloy target material is uniform in component, free of segregation, uniform in grain size and high in density.

Description

Technical Field

[0001] The invention belongs to the field of magnetron sputtering target material preparation, and specifically relates to an aluminum-neodymium-zinc alloy target material for magnetron sputtering and a manufacturing method thereof. Background Art

[0002] In magnetron sputtering coating, electrons are accelerated to fly to the substrate under the action of the electric field, and collide with argon atoms, ionizing a large number of argon positive ions and new electrons. The new electrons fly to the substrate, and the argon ions are accelerated to fly to the cathode target under the action of the electric field, and bombard the target surface with high energy, causing the target material to sputter. A large number of target atoms are sputtered, and the neutral target atoms are deposited on the substrate to form a film, and finally the purpose of coating the substrate surface is achieved.

[0003] As an important consumable for sputtering coating, the quality of the target material is directly related to the quality of the coated product. For example, the composition, purity, density, porosity, grain size and uniformity of the target material all affect the quality of the coated product and the sputtering rate. For alloy sputtering targets, there is often an uneven distribution of materials. The segregation of the target material composition will affect the sputtering rate, the uniformity of the coated product and the composition of the coated product. Therefore, in addition to controlling the purity of the target material, the distribution of the alloy target material is also critical. Segregation refers to the uneven distribution of the elements in the alloy, which usually leads to a reduction in the performance of the alloy and may even cause a series of engineering problems.

[0004] Aluminum-neodymium alloy is a commonly used magnetron sputtering target. Segregation of aluminum-neodymium alloy targets is a common problem encountered during material preparation and processing. Because the melting point of aluminum is 660℃, the density is 2.7, and the thermal conductivity is 0.53; the melting point of neodymium is 1024℃, the density is 7.0, and the thermal conductivity is 0.031. Due to the large differences in their melting points, densities, and thermal conductivity, segregation and splashing are easily generated during the smelting process, causing pollution, leading to uneven alloy structure and high impurity content, which seriously affects the quality of the alloy and leads to a decrease in the mechanical properties of the alloy, such as a decrease in performance indicators such as strength, toughness, and wear resistance, which may affect the service life and safety of the product.

[0005] In the prior art, the casting stress of the alloy can be effectively eliminated to a certain extent through hot forging, rolling treatment and annealing processes, so as to homogenize the composition, thereby improving the density of the target material and the uniformity of the grain size distribution. CN103184419B is a method for producing an aluminum-neodymium alloy target material, wherein high-purity aluminum and neodymium single metals are cast into ingots by vacuum melting under specific conditions; and then the aluminum-neodymium alloy target material is obtained by heat treatment, forging, rolling and machining under specific conditions. CN107619972B relates to a method for manufacturing an aluminum-neodymium alloy for magnetron sputtering targets. The manufacturing method is divided into two steps. The first step is to prepare an aluminum-neodymium intermediate alloy using aluminum and neodymium as raw materials, and the second step is to prepare an aluminum-neodymium alloy using aluminum and aluminum-neodymium intermediate alloy as raw materials. The main problem to be solved is the splashing problem of neodymium during the smelting process. The target material obtained according to the method described in the patent does not have a sufficiently uniform alloying structure. CN114959595B relates to a high-purity aluminum-neodymium alloy target for sputtering and a method for manufacturing the same. High-purity aluminum and aluminum-neodymium master alloy are used as raw materials. High-purity aluminum and aluminum-neodymium master alloy blocks in a specific proportion are weighed, smelted at high temperature in a vacuum smelting furnace, then smelted at low temperature, vacuum cast into a vacuum water-cooled mold lined with high-purity alumina and rapidly cooled. After obtaining a cast square embryo, the embryo is kept warm and homogenized, and then rolled. The rolled alloy plate embryo is annealed and machined.

[0006] The problem to be solved by the present invention is to provide a target material with small internal component segregation, dense and uniform structure, and better wear resistance than aluminum-neodymium alloy target material, which can replace aluminum-neodymium alloy and a manufacturing method thereof. Summary of the invention

[0007] Based on this, the object of the present invention is to provide an aluminum-neodymium-zinc alloy target for magnetron sputtering and a method for manufacturing the same, so as to obtain an aluminum-neodymium-zinc alloy target with uniform composition, no segregation, uniform grain size and high density.

[0008] One of the purposes of the present invention is to provide an aluminum-neodymium-zinc alloy target for magnetron sputtering, wherein the aluminum-neodymium-zinc alloy target has a neodymium content of 1wt% to 20wt%, a zinc content of 1wt% to 20wt%, and the remainder is aluminum; wherein the difference between the neodymium content and the zinc content is within 5wt%; the purity of the aluminum-neodymium-zinc alloy target is 2N-5N, and the average grain size is 10μm-150μm.

[0009] Another object of the present invention is to provide a method for preparing an aluminum-neodymium-zinc alloy target for magnetron sputtering, comprising the following steps: Step 1, preparing an aluminum-neodymium master alloy containing a neodymium content of 10% to 30%, such as an Al-30%Nd aluminum-neodymium master alloy or an Al-10%Nd aluminum-neodymium master alloy; using high-purity aluminum and high-purity neodymium with a purity of 2N-5N.

[0010] Step 2, adding the aluminum-neodymium master alloy, high-purity zinc and high-purity aluminum to a vacuum melting furnace, melting, refining and casting to obtain an aluminum-neodymium-zinc alloy ingot; the aluminum-neodymium-zinc alloy ingot has a high-purity neodymium content of 1wt% to 20wt%, a high-purity zinc content of 1wt% to 20wt%, and a ratio of high-purity zinc to high-purity neodymium that is within 5%.

[0011] Step 3, subjecting the aluminum-neodymium-zinc alloy ingot to homogenization annealing, machining, rolling, and recrystallization annealing in sequence to obtain an aluminum-neodymium-zinc target.

[0012] Further, in step 1, the preparation method of the aluminum-neodymium intermediate alloy is specifically to add the high-purity aluminum and the high-purity neodymium to a crucible at the same time in a ratio of 7 to 9:1 to 3, and perform vacuum medium-frequency induction melting, with a vacuum degree of ≤10Pa, a melting power of 65KW, and a melting temperature of 900°C; after the metallic aluminum and the metallic neodymium are completely melted, the melting power is adjusted to 40KW for refining for 10 minutes, and then the molten alloy is cast into a mold.

[0013] Furthermore, in step 2, the melting temperature is 800° C., the vacuum degree is ≤10 Pa, the power is 70 KW, and the refining power is 40 KW.

[0014] Furthermore, the homogenization annealing temperature in step 3 is 200-600° C., and the annealing time is 6-12 hours to eliminate grain boundary segregation.

[0015] Furthermore, in step 3, the deformation amount of each of the first three rolling passes is 10% to 30%, and the deformation amount of each subsequent rolling pass is 30% to 50%; the total deformation rate is 60% to 90%. Preferably, the temperature before rolling is kept at 200 to 600°C for 2 to 6 hours.

[0016] Furthermore, the recrystallization annealing temperature in step 3 is 200-550° C., and the holding time is 2-5 hours.

[0017] The beneficial effects of the present invention are as follows: (1) zinc element is added to the aluminum-neodymium alloy target material to replace the original aluminum-neodymium alloy target material, the internal component segregation degree is small, the structure is dense and uniform, and the wear resistance is better than that of the aluminum-neodymium alloy target material. The hardness is increased from 50-150HB of aluminum-neodymium alloy to 150-200HB of aluminum-neodymium-zinc alloy, the film strength and corrosion resistance are improved, and it is used as a coating material in the display panel industry to provide better film performance; (2) The present invention uses aluminum, zinc, and aluminum-neodymium intermediate alloys. After a specific vacuum melting, casting process and homogenization annealing, the alloy ingot is obtained, and the neodymium and zinc elements are evenly distributed inside, without segregation and intermediate compounds. Through subsequent hot rolling and recrystallization annealing, an aluminum-neodymium-zinc alloy target with high purity, high alloy degree, good structural consistency, fine grains and no internal defects can be obtained; (3) The aluminum-neodymium-zinc target prepared by the present invention has uniform structure, sufficient alloying, and appropriate and uniform grain size, which is conducive to obtaining a dense sputtering film and a uniform film thickness. It is mainly used in the process of preventing the diffusion of the metal layer in the manufacturing process of flat-panel displays; or for connecting metal wiring electrodes in the field of flat-panel displays; it can also prepare high-quality aluminum-neodymium-zinc films for magnetic storage devices, sensors and optical coatings. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a metallographic image of the aluminum-neodymium-zinc alloy ingot after homogenization annealing in Example 1 of the present invention.

[0019] Figure 2 This is the metallographic diagram of the aluminum-neodymium-zinc alloy after recrystallization heat treatment in Example 1 of the present invention.

[0020] Figure 3 This is the metallographic image of the aluminum-neodymium-zinc alloy after recrystallization heat treatment in Example 2 of the present invention. DETAILED DESCRIPTION

[0021] In order to better understand the technical solution of the present invention, the embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. It should be clear that the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0022] Unless otherwise specified, the test materials and equipment used in the examples are common commercial products and can be purchased in the market.

[0023] In order to better understand and implement the present invention, the present invention is described in detail below in conjunction with specific embodiments.

[0024] Example 1

[0025] (1) High-purity aluminum and high-purity neodymium (purity ≥ 99.99%) are added to an alumina crucible at a ratio of 7:3, and vacuum medium-frequency induction melting is performed, with a vacuum degree of ≤10Pa, a melting power of 65KW, and a melting temperature of 900°C. After the metal aluminum and metal neodymium are completely melted, the melting temperature is adjusted to 40KW, and the refining is performed for 10 minutes. The refined alloy melt is cast into an iron mold to obtain an Al-30%Nd aluminum-neodymium master alloy.

[0026] (2) The Al-30% Nd aluminum-neodymium master alloy, high-purity zinc (purity ≥ 99.9%) and high-purity aluminum obtained in step (1) are added to an alumina crucible at a weight ratio of 8.3:2:89.7, and vacuum medium-frequency induction melting is performed, the vacuum degree is ≤10Pa, the melting power is 70KW, and the melting temperature is 800°C. After all the raw materials are melted, the melting power is adjusted to 40KW, and the refining is performed for 10 minutes. The refined alloy melt is cast into an iron mold through a zirconium oxide filter to obtain an aluminum-neodymium-zinc alloy ingot (Al-2.5% Nd-2% Zn).

[0027] (3) subjecting the Al-2.5%Nd-2%Zn aluminum-neodymium-zinc alloy ingot to homogenization annealing at a temperature of 500°C for 10 hours, and removing the surface oxide scale and head shrinkage cavity; Figure 1 This is a metallographic image of the aluminum-neodymium-zinc alloy ingot after homogenization annealing in Example 1 of the present invention.

[0028] (4) heating the machined aluminum-neodymium-zinc ingot to 400° C., keeping the temperature for 3 hours, and then rolling the ingot. The deformation of each of the first three rolling passes is 16%, the deformation of each of the subsequent rolling passes is 35%, and the total deformation rate is 80%;

[0029] (5) The rolled aluminum-neodymium-zinc sheet is subjected to recrystallization annealing at a temperature of 450°C for a holding time of 4 hours. The average grain size after recrystallization annealing is 40 μm. Figure 2 This is a metallographic diagram of the aluminum-neodymium-zinc alloy after recrystallization heat treatment in Example 1 of the present invention.

[0030] (6) machining to obtain an aluminum-neodymium-zinc target of a specified size, grinding the surface of the target to obtain an aluminum-neodymium-zinc alloy target with no pits, scratches, oxidation, and uniform surface roughness.

[0031] Ultrasonic nondestructive testing was performed on the obtained aluminum-neodymium-zinc target to measure its composition, purity, density and other parameters. The results are as follows: the composition contains 2.5% neodymium and 2% zinc; the purity is greater than 99.9wt%, and the relative density is greater than 99.9wt%. Figure 1 It can be seen that the alloy target is fully uniformly alloyed and dense, the internal neodymium element is evenly distributed, and there is no serious segregation. Figure 2 It can be seen that the average grain size of the alloy target is uniform, and there is no grain stratification or abnormally grown grains.

[0032] Example 2

[0033] (1) High-purity aluminum and high-purity neodymium (purity ≥ 99.99%) are added to an alumina crucible at a ratio of 7:3, and vacuum medium-frequency induction melting is performed, with a vacuum degree of ≤10Pa, a melting power of 65KW, and a melting temperature of 900°C. After the metal aluminum and metal neodymium are completely melted, the melting temperature is adjusted to 40KW, and the refining is performed for 10 minutes. The refined alloy melt is cast into an iron mold to obtain an aluminum-neodymium intermediate alloy (Al-30%Nd).

[0034] (2) The Al-30% Nd aluminum-neodymium master alloy, high-purity zinc (purity ≥ 99.9%) and high-purity aluminum obtained in step (1) are added to an alumina crucible at the same time in a ratio of 16.7:4:79.3, and vacuum medium-frequency induction melting is performed, the vacuum degree is ≤10Pa, the melting power is 70KW, and the melting temperature is 800°C. After all the raw materials are melted, the melting power is adjusted to 40KW, and the refining is performed for 10 minutes. The refined alloy melt is cast into an iron mold through a zirconium oxide filter to obtain an aluminum-neodymium-zinc alloy ingot (Al-5% Nd-4% Zn).

[0035] (3) subjecting the Al-5%Nd-4%Zn aluminum-neodymium-zinc alloy ingot to homogenization annealing at a temperature of 500°C for 10 hours, and removing the surface oxide scale and head shrinkage cavity;

[0036] (4) The aluminum-neodymium-zinc ingot machined in step (3) is heated to 400° C., kept at this temperature for 4 hours, and then rolled, with the deformation of each of the first three passes being 18%, the deformation of each of the subsequent passes being 30%, and the total deformation rate being 85%, to obtain an aluminum-neodymium-zinc plate.

[0037] (5) The rolled aluminum-neodymium-zinc sheet is subjected to recrystallization annealing at a temperature of 500°C for a holding time of 4 hours. The average grain size after recrystallization annealing is 67 μm. Figure 3 This is the metallographic image of the aluminum-neodymium-zinc alloy after recrystallization heat treatment in Example 2. Figure 3 It can be seen that the alloy target is fully uniformly and densely alloyed, the neodymium element is evenly distributed inside, and there is no serious segregation.

[0038] (6) machining to obtain an aluminum-neodymium-zinc target of a specified size, grinding the surface of the target to obtain an aluminum-neodymium-zinc alloy target with no pits, scratches, oxidation, and uniform surface roughness.

[0039] Table 1 Example 1-Example 4

[0040]

[0041]

[0042] Example 5

[0043] (1) High-purity aluminum and high-purity neodymium (purity ≥ 99.99%) are added to an alumina crucible at a ratio of 9:1, and vacuum medium-frequency induction melting is performed, with a vacuum degree of ≤10Pa, a melting power of 65KW, and a melting temperature of 900°C. After the metal aluminum and metal neodymium are completely melted, the melting temperature is adjusted to 40KW, and the refining is performed for 10 minutes. The refined alloy melt is cast into an iron mold to obtain an Al-10%Nd aluminum-neodymium master alloy.

[0044] (2) Weigh 12.5 kg of the Al-10% Nd aluminum-neodymium master alloy obtained in step (1), 1 kg of high-purity zinc (purity ≥ 99.9%) and 36.5 kg of high-purity aluminum in a ratio of 25:2:73 and add them to an alumina crucible at the same time, and perform vacuum medium-frequency induction melting, with a vacuum degree of ≤10 Pa, a melting power of 70 KW, and a melting temperature of 800°C. After all the raw materials are melted, adjust the melting power to 40 KW and perform refining for 10 minutes. Cast the refined alloy melt into an iron mold through a zirconium oxide filter to obtain an aluminum-neodymium-zinc alloy ingot (Al-2.5% Nd-2% Zn).

[0045] (3) The Al-2.5%Nd-2%Zn aluminum-neodymium-zinc alloy ingot is subjected to homogenization annealing treatment at a temperature of 500°C for a holding time of 10 hours, and the surface oxide scale and head shrinkage cavity are removed.

[0046] (4) heating the machined aluminum-neodymium-zinc ingot to 400° C., keeping the temperature for 3 hours, and then rolling it. The deformation of each of the first three rolling passes is 10%, and the deformation of each subsequent rolling pass is 35%, with a total deformation rate of 70%;

[0047] (5) After rolling, the aluminum-neodymium-zinc sheet was recrystallized and annealed at 450°C for 4 hours. The average grain size after recrystallization annealing was 40 μm. The metallographic image of the aluminum-neodymium-zinc alloy showed that the alloying was fully uniform and dense, the internal neodymium element was evenly distributed, and there was no serious segregation.

[0048] (6) machining to obtain an aluminum-neodymium-zinc target of a specified size, grinding the surface of the target to obtain an aluminum-neodymium-zinc alloy target with no pits, scratches, oxidation, and uniform surface roughness.

[0049] Example 6, following the steps of Example 5, the difference is that the Al-10%Nd aluminum-neodymium master alloy, high-purity zinc and high-purity aluminum are in a ratio of 50:4:46 to produce an Al-5%Nd-4%Zn aluminum-neodymium-zinc alloy ingot.

[0050] The Al-5%Nd-4%Zn aluminum-neodymium-zinc alloy ingot was subjected to homogenization annealing treatment, with an annealing temperature of 500℃ and a holding time of 10 hours, and the surface oxide scale and head shrinkage cavity were removed; the aluminum-neodymium-zinc ingot after machining was heated to 400℃, kept warm for 4 hours, and then rolled, with a deformation of 10% in each of the first three passes of rolling, and a deformation of 40% in each subsequent pass, with a total deformation rate of 83%. The aluminum-neodymium-zinc plate was obtained. The aluminum-neodymium-zinc plate after rolling was subjected to recrystallization annealing, with an annealing temperature of 500℃ and a holding time of 4 hours. The average grain size after recrystallization annealing was 67μm. It was observed from the metallographic diagram of the aluminum-neodymium-zinc alloy that its alloying was fully uniform and dense, the internal neodymium element was evenly distributed, and there was no serious segregation. The aluminum-neodymium-zinc target of the specified size was obtained by machining, and the surface of the target was ground to obtain an aluminum-neodymium-zinc alloy target with no pits, scratches, oxidation, and uniform surface roughness.

[0051] The hardness of the aluminum-neodymium-zinc alloy of test examples 1-6 can reach 150-200HB. The hardness of aluminum-neodymium alloy is generally 50-150HB. Adding zinc element to the aluminum-neodymium alloy target material to replace the original aluminum-neodymium alloy target material has a small internal component segregation, a dense and uniform structure, and better wear resistance than the aluminum-neodymium alloy target material, and the hardness is improved, and the film strength and corrosion resistance are improved. It is used as a coating material in the display panel industry to provide better film performance.

[0052] The above-mentioned embodiments only express several implementation methods of the present invention, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the invention patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. An aluminum-neodymium-zinc alloy target for magnetron sputtering, characterized in that: The aluminum-neodymium-zinc alloy target has a neodymium content of 1wt% to 20wt%, a zinc content of 1wt% to 20wt%, and the balance is aluminum; the difference between the neodymium content and the zinc content is within 5wt%; the aluminum-neodymium-zinc alloy target has a purity of 2N-5N, and an average grain size of 10μm-150μm.

2. A method for preparing an aluminum-neodymium-zinc alloy target for magnetron sputtering, characterized in that: The following steps are involved: Step 1, preparing an aluminum-neodymium master alloy containing 10% to 30% neodymium, using high-purity aluminum and high-purity neodymium with a purity of 2N-5N; Step 2, adding the aluminum-neodymium master alloy, high-purity zinc and high-purity aluminum to a vacuum melting furnace, melting, refining and casting to obtain an aluminum-neodymium-zinc alloy ingot; the difference between the high-purity zinc and high-purity neodymium components in the aluminum-neodymium-zinc alloy ingot is within 5%; Step 3, subjecting the aluminum-neodymium-zinc alloy ingot to homogenization annealing, machining, rolling, and recrystallization annealing in sequence to obtain an aluminum-neodymium-zinc target.

3. The preparation method according to claim 2, characterized in that: In step 1, the preparation method of the aluminum-neodymium intermediate alloy containing a neodymium content of 10% to 30% is specifically to add the high-purity aluminum and the high-purity neodymium to a crucible at the same time in a ratio of 7 to 9:1 to 3, and perform vacuum medium-frequency induction melting, the vacuum degree ≤10Pa, the melting power 65KW, and the melting temperature 900°C; after the metallic aluminum and the metallic neodymium are completely melted, the melting power is adjusted to 40KW for refining for 10 minutes, and then the molten alloy is cast into a mold.

4. The preparation method according to claim 2, characterized in that: In step 2, the melting temperature is 800° C., the vacuum degree is ≤10 Pa, the power is 70 KW, and the refining power is 40 KW.

5. The preparation method according to claim 2, characterized in that: In step 3, the homogenization annealing temperature is 200-600° C., and the annealing time is 6-12 hours.

6. The preparation method according to claim 2, characterized in that: In step 3, the deformation amount of each of the first three passes of the rolling process is 10% to 30%, and the deformation amount of each subsequent pass is 30% to 50%; the total deformation rate is 60% to 90%.

7. The preparation method according to claim 6, characterized in that: The temperature before the rolling treatment is 200-600° C. and the holding time is 2-6 hours.

8. The preparation method according to claim 2, characterized in that: In step 3, the recrystallization annealing temperature is 200-550° C., and the holding time is 2-5 hours.

Images