Preparation and application of silver-palladium-copper alloy target material
By precisely controlling the content of silver, palladium, and copper, and adding grain refiners, combined with multi-pass cold rolling and annealing processes, the microscopic uniformity problem of silver-palladium-copper alloy targets was solved, and high-performance silver-palladium-copper alloy targets were prepared, which are suitable for high-end optoelectronic devices.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- YAXIN SEMICON MATERIALS (JIANGSU) CO LTD
- Filing Date
- 2026-04-23
- Publication Date
- 2026-06-05
AI Technical Summary
Existing technologies make it difficult to prepare silver-palladium-copper alloy targets with good microstructure uniformity and excellent performance, resulting in uneven film composition and performance, which affects the consistency and yield of devices.
Through processes such as vacuum melting, inert gas atomization, solution treatment, multi-pass cold rolling and intermediate annealing, and recrystallization annealing, the content of silver, palladium, and copper, as well as the addition of grain refiners, are precisely controlled to ensure the uniformity of alloy composition and mechanical strength, and to achieve a balance between reflectivity, conductivity, and environmental stability.
A silver-palladium-copper alloy target material with precise composition, uniform structure, and high density was prepared, which improved the overall performance consistency and service life of the target material and is suitable for high-end optoelectronic devices.
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Abstract
Description
Technical Field
[0001] This invention belongs to the field of metal alloy target manufacturing technology, and relates to the preparation and application of a silver-palladium-copper alloy target material. Background Technology
[0002] Metallic silver possesses high conductivity and reflectivity. Magnetron sputtering of silver thin films using silver targets as electrode films, reflective films, or wiring films is widely used in organic EL displays, light-emitting diodes (LEDs), touch screens, and optical recording media. However, silver is expensive, resulting in high-cost target materials. Furthermore, silver's inherent limitations in heat resistance, salt water resistance, reliability, sulfur resistance, and migration resistance severely restrict its long-term reliability applications in high-end optoelectronic devices. For example, pure silver thin films are rarely used in high-precision touch panels, flexible OLEDs, and Mini / Micro-LEDs.
[0003] To address the aforementioned issues, alloying methods are typically employed. Silver-based thin films made from silver-based alloys possess several superior properties, such as high reflectivity, high transmittance, low extinction coefficient, high thermal conductivity, low resistivity, and excellent surface smoothing. Chinese invention patent application CN114293155A discloses a method for preparing a silver-palladium-copper alloy target material, which involves controlled atmosphere cold spraying and rolling. This process is complex and requires strict pretreatment of raw materials, posing significant challenges to production stability. Chinese invention patent application CN115044877A discloses a method for preparing a silver-based ternary alloy target material, which effectively reduces energy consumption through a two-step melting method. However, it fails to fundamentally overcome the micro-composition segregation problem caused by melting-casting, and the step-by-step addition cannot ensure the uniformity of the alloy liquid after melting. Chinese invention patent application C... N120719260A discloses a method for preparing an AgPdCu alloy sputtering target. The method employs a plastic processing route of vacuum melting, homogenization annealing, high-temperature hot rolling, multi-pass cold rolling, and annealing / hot isostatic pressing. The hot and cold rolling processes have stringent requirements, and due to the significant differences in melting point and density among silver, palladium, and copper, microscopic or macroscopic compositional segregation easily occurs during solidification. Even with subsequent high-temperature homogenization annealing and intense plastic deformation, it is difficult to completely eliminate the dendritic segregation formed in the initial ingot, resulting in insufficient microscopic compositional uniformity of the final target material. This non-uniformity leads to fluctuations in film composition and properties during sputtering, affecting device consistency and yield.
[0004] Therefore, developing a silver-palladium-copper alloy target and its preparation method that can ensure high uniformity of alloy composition at the microscale, take into account process feasibility and cost controllability, and stably prepare thin films with comprehensive excellent performance has become an urgent technical problem to be solved in this field. Summary of the Invention
[0005] The technical problem to be solved by the present invention is: in view of the above-mentioned defects, the present invention provides a silver-palladium-copper alloy target material preparation. The alloy target material has a uniform microstructure distribution, high mechanical strength, corrosion resistance and high temperature oxidation resistance. The preparation process achieves an excellent balance between reflectivity, conductivity, environmental stability and processability.
[0006] The technical solution adopted by this invention to solve its technical problem is as follows: Preparation of a silver-palladium-copper alloy target material, wherein the target material comprises 0.5wt%-5.0wt% palladium, 0.1wt%-3.0wt% copper, 0.01wt%-0.05wt% grain refiner, and the balance being silver; the preparation of the target material includes the following steps:
[0007] Step S1, Material preparation: Weigh out palladium, copper and silver powder according to the weight composition of the silver-palladium-copper alloy target material, and set aside for use;
[0008] Step S2, Vacuum Melting: Turn on the vacuum induction melting device, evacuate, and fill with high-purity argon gas to a slightly positive pressure; put metallic copper and metallic palladium into a crucible, heat until molten metal appears, add silver powder, and heat until the solid melts completely; after melting, an alloy liquid is obtained, and it is kept at 1300℃-1400℃ for a period of time, and the electromagnetic stirring is turned on.
[0009] Step S3, blank preparation: Add grain refiner to alloy liquid, stir evenly, and then introduce the liquid into inert gas atomization equipment to obtain fine spherical powder. After the powder is sieved, it is packed into a sleeve, vacuum sealed, and kept warm and pressured to form a blank.
[0010] Step S4, solution treatment: control the temperature of the blank in the single-phase region, hold it at that temperature for a certain time, and then quickly quench it in water to obtain a supersaturated solid solution.
[0011] Step S5, cold working and intermediate annealing: The supersaturated solid solution is cold rolled in multiple passes, and after single or double cold rolling, an intermediate annealing is performed. The total processing deformation is 80%-90% to obtain the initial target material.
[0012] Step S6, recrystallization annealing: The annealed initial target material is held at 700℃-800℃ to obtain a silver-palladium-copper alloy plate.
[0013] Step S7, finishing: The silver-palladium-copper alloy plate after recrystallization annealing is surface-finished to the required size and surface roughness to obtain the silver-palladium-copper alloy target.
[0014] By employing the above technical solution, the composition of the silver-palladium-copper alloy target material achieves an optimized balance between conductivity, strength, and corrosion resistance through precise control of the silver, palladium, and copper content. The introduction of a trace grain refiner effectively refines the original grains, laying the foundation for obtaining a uniform and fine final microstructure, thereby improving the overall performance consistency of the target material.
[0015] The preparation of the target material ensures its quality through full-process process control. In the vacuum melting step, copper and palladium are melted first, followed by the addition of silver powder, combined with high-temperature holding and electromagnetic stirring. This ensures the full melting and dissolution of high-melting-point components and achieves highly uniform mixing of all elements in the liquid state, effectively avoiding component segregation. Fine spherical powder is prepared using an inert gas atomization method. This powder has controllable particle size, high sphericity, low oxygen content, and uniform composition, providing ideal raw materials for obtaining high-density, uniformly composed billets through hot isostatic pressing or hot pressing. In the solution treatment operation, the billet is heated to the single-phase region, held at that temperature, and then rapidly water-quenched. This allows alloying elements, especially copper, to fully dissolve into the silver matrix, forming a supersaturated solid solution. This creates conditions for obtaining a recrystallized fine-grained structure through subsequent cold working and annealing. Cold rolling with a total deformation of 80%-90%, interspersed with intermediate annealing, effectively breaks down coarse grains, introduces high-density dislocations, provides numerous nucleation sites for recrystallization, and prevents cracking due to excessive work hardening. Intermediate annealing eliminates internal stress, restores plasticity, and facilitates further large deformation processing. Recrystallization annealing at 700℃-800℃ allows complete recrystallization of the material after large deformation, resulting in a fine, uniform equiaxed grain structure.
[0016] Through precise control of the entire process, the final silver-palladium-copper alloy target material has advantages such as accurate composition, uniform and fine structure, controllable grain size, high density, and low impurity content. These characteristics can be directly converted into excellent sputtering performance, including stable discharge, uniform film formation rate, high-quality thin film, and longer target life.
[0017] Furthermore, in step S2, the vacuum melting process is performed with the vacuum level reduced to 1.0 × 10⁻⁶. -2 Pa-5.0×10 -2 Pa; the temperature before adding silver powder is 1050℃-1150℃, and the temperature after adding silver powder is 1500℃-1600℃; after melting and clearing, the alloy liquid is cooled to the holding temperature and held at the holding temperature for 15 minutes-30 minutes; the crucible is a magnesium oxide crucible or a graphite crucible.
[0018] Using the above technical solution, the vacuum melting operation is first protected by high vacuum and slightly positive pressure argon gas, which can minimize alloy oxidation and gas absorption, ensuring high purity of the melt from the source. Now, copper and palladium are melted at 1050-1150℃. After adding silver powder, the temperature is increased, and after melting thoroughly, electromagnetic stirring is used to effectively prevent component segregation and promote uniform elemental miscibility. Magnesium oxide or graphite crucibles are selected, and their high-temperature chemical inertness avoids the introduction of impurities. This step works synergistically to provide a foundation for a high-purity alloy melt with precise composition and high homogeneity for subsequent processes.
[0019] Furthermore, the grain refiner is one or more of yttrium, yttrium oxide, and rare earth metals. Using yttrium, yttrium oxide, or rare earth metals as grain refiners can increase the nucleation rate, effectively refine the alloy's solidification structure, and facilitate the acquisition of uniform and fine final grains in subsequent processing. This further improves the material's compositional uniformity, reduces segregation, and is beneficial for improving the alloy's hot working properties and mechanical properties.
[0020] Furthermore, in step S3 of the raw material preparation, the sieve particle size for powder sieving is 100-500 mesh; the temperature for heat preservation and pressure holding after vacuum sealing is 850℃-950℃, the pressure is 100MPa-150MPa argon pressure, and the heat preservation and pressure holding time is 2 hours-4 hours.
[0021] By employing the above technical solutions, controlling the sieve particle size (i.e., controlling the powder particle size) during powder sieving can yield powder with good filling properties and a suitable particle size, laying the foundation for subsequent densification. Optimizing the hot isostatic pressing process, utilizing high temperature and high pressure, can effectively eliminate porosity between powder particles, significantly improving the density and internal quality of the raw material. Through process control, loose powder can be directly processed into highly dense, defect-free, and uniformly composed raw materials.
[0022] Furthermore, in step S4, the single-phase region temperature is 800-950℃, and the holding time is 30 minutes to 2 hours. By controlling the temperature and time during the solution treatment, the alloy can be heated to a single austenitic phase region, allowing alloying elements such as copper to fully dissolve into the silver matrix, forming a supersaturated single solid solution. This eliminates component segregation and microscopic inhomogeneity in the billet.
[0023] Furthermore, in step S5, the single-pass cold rolling deformation in cold working and annealing is 15%-30%; the intermediate annealing temperature is 650℃-750℃, and the time is 15-30 minutes. This step, through a cycle of "moderate cold deformation + medium-temperature short-time annealing," achieves the total deformation while continuously refining the grains, homogenizing the microstructure, maintaining good material machinability, and avoiding defects.
[0024] Furthermore, in step S5, cold working and annealing, hardness is measured after each cold rolling pass. If the hardness increase is less than 30%, an intermediate annealing is performed after two passes; if the hardness increase is greater than 30%, an intermediate annealing is performed after each cold rolling pass. By adopting the above technical solution, this process dynamically adjusts the annealing frequency based on hardness changes, optimizes the processing flow, and effectively achieves a balance between ensuring processing efficiency and preventing material failure, resulting in a stable and reliable process.
[0025] Furthermore, in step S6, the recrystallization annealing is held at a temperature of 30 minutes to 2 hours. Controlling the recrystallization annealing time provides sufficient time for atomic diffusion and grain boundary migration to complete the recrystallization nucleation and growth process, while avoiding excessive grain growth due to excessive annealing time, which would reduce the material strength. This process can effectively control the grain size, ultimately enabling the target material to obtain a fine, uniform, and high-performance stable microstructure.
[0026] Furthermore, the silver-palladium-copper alloy target material can be square, circular, columnar, or irregularly shaped. The preparation process and material of this silver-palladium-copper alloy target material exhibit good adaptability and application flexibility, capable of meeting the needs of different sputtering equipment and diverse coating requirements, as well as the requirements for target shape.
[0027] An application of a silver-palladium-copper alloy sputtering target material is disclosed. This silver-palladium-copper alloy sputtering target material is used for reflective films in optical discs, electrodes for LCDs, OLEDs, and LEDs, and wiring materials for touchscreens. Through composition and process optimization, this silver-palladium-copper alloy sputtering target material achieves an excellent balance between reflectivity, conductivity, environmental stability, and processability, making it an ideal sputtering source material for preparing high-performance, high-reliability optical disc reflective films, flat panel display electrodes, and precision wiring, among other key functional thin films, with a wide range of applications.
[0028] The beneficial effects of this invention are:
[0029] 1. By adopting the above scheme, specific amounts of palladium, copper and grain refiner are precisely added to the silver-based alloy. While maintaining the excellent electrical and thermal conductivity of silver, the mechanical strength, corrosion resistance and high-temperature oxidation resistance of the alloy are improved. At the same time, grain refinement helps to improve subsequent processing performance and improve the uniformity of the microstructure of the target material.
[0030] 2. The preparation process of this invention employs high vacuum and inert gas protected melting, effectively preventing oxidation and gas absorption during alloy melting and ensuring the purity of the alloy. Electromagnetic stirring promotes the homogenization of the alloy composition and reduces segregation; fine spherical powder is prepared by inert gas atomization and sieved, resulting in powder with good flowability and uniform particle size. Subsequent vacuum sealing and heat and pressure holding densify the powder blank, eliminating internal defects and obtaining a uniform and fine initial microstructure; after solution treatment in the single-phase region followed by water quenching, palladium, copper, and other alloying elements are fully dissolved in the silver matrix, forming a supersaturated solid solution, creating conditions for subsequent processing.
[0031] 3. In the cooling process, this technology uses multi-pass cold rolling to achieve large deformation, combined with intermediate annealing. The annealing frequency and pass number are flexibly adjusted according to the hardness changes, which can effectively break up grains and increase dislocation density. At the same time, intermediate annealing eliminates work hardening, restores plasticity, and avoids the risk of cracking. Ultimately, it significantly refines grains and improves the strength and toughness of the material. Finally, recrystallization annealing can eliminate residual stress and obtain a uniform, equiaxed recrystallized grain structure, giving the target material good plasticity, stable performance and excellent sputtering uniformity.
[0032] 4. This process employs a complete and precise preparation flow, including vacuum melting, atomization powdering, hot isostatic pressing for densification, solution treatment, controlled rolling annealing with large deformation, and recrystallization annealing. This allows for effective control over the microstructure and macroscopic properties of the alloy sputtering target, resulting in high-performance, high-quality silver-palladium-copper alloy sputtering targets. The prepared targets exhibit excellent adaptability to applications requiring high thin-film conductivity, reflectivity, adhesion, and stability. They also demonstrate high migration resistance, low electrical resistance, scratch resistance, and can withstand roll-to-roll production processes on flexible substrates, making them suitable for a wide range of applications. Detailed Implementation
[0033] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to examples. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.
[0034] Example 1
[0035] Preparation of a silver-palladium-copper alloy target material, wherein the target material comprises 2.0 wt% palladium, 1.5 wt% copper, 0.01 wt% yttrium, and the balance being silver;
[0036] The preparation of the target material includes the following steps:
[0037] Step S1, Material preparation: Weigh out palladium, copper and silver powder according to the weight composition of the silver-palladium-copper alloy target material, and set aside for use;
[0038] Step S2, Vacuum Melting: Turn on the vacuum induction melting device and evacuate to a vacuum level of 2.0 × 10⁻⁶. -2 Pa, fill with high-purity argon to a slightly positive pressure; put metallic copper and metallic palladium into a magnesium oxide crucible, heat to 1110℃, when molten metal appears, add silver powder, heat to 1550℃ until the solid melts; after melting, the alloy liquid is obtained, and it is kept at 1350℃ for 20 minutes while the electromagnetic stirring is turned on.
[0039] Step S3, blank preparation: Add yttrium metal to the alloy liquid, stir evenly, and then introduce the liquid into an inert gas atomization device to obtain fine spherical powder. The powder is sieved with a sieve particle size of 200 mesh, sieved and packed into a sleeve, vacuum sealed, and kept at 900℃ and 120 MPa argon pressure for 3 hours to form a blank.
[0040] Step S4, solution treatment: control the temperature of the blank in the single-phase region, the temperature is 850℃, hold for 1 hour and then quickly water quench to obtain a supersaturated solid solution.
[0041] Step S5, cold working and intermediate annealing: The supersaturated solid solution is subjected to multi-pass cold rolling, with a single-pass cold rolling deformation of 15%-20%. After the single-pass cold rolling is completed, the hardness is measured. When the hardness increase is less than 30%, an intermediate annealing is performed after two passes. When the hardness increase is greater than 30%, an intermediate annealing is performed after the single-pass cold rolling. The intermediate annealing temperature is 700℃, the annealing time is 20 minutes, and the total processing deformation is 90%, thus obtaining the initial target material.
[0042] Step S6, recrystallization annealing: The annealed initial target material is held at 700℃ for 1 hour to obtain a silver-palladium-copper alloy plate.
[0043] Step S7, finishing: The silver-palladium-copper alloy plate after recrystallization annealing is surface-machined to the required size and surface roughness to obtain the silver-palladium-copper alloy target material; in this embodiment, the shape of the silver-palladium-copper alloy target material is processed into a square plate structure for use in high-precision OLED electrodes.
[0044] Example 2
[0045] Preparation of a silver-palladium-copper alloy target material, wherein the target material comprises 0.5 wt% palladium, 2.0 wt% copper, 0.05 wt% yttrium oxide, and the balance being silver;
[0046] The preparation of the target material includes the following steps:
[0047] Step S1, Material preparation: Weigh out palladium, copper and silver powder according to the weight composition of the silver-palladium-copper alloy target material, and set aside for use;
[0048] Step S2, Vacuum Melting: Turn on the vacuum induction melting device and evacuate to 5.0 × 10⁻⁶. -2 Pa, fill with high-purity argon to a slightly positive pressure; put metallic copper and metallic palladium into a graphite crucible, heat to 1050℃, when molten metal appears, add silver powder, heat to 1500℃ until the solid melts, after melting, the alloy liquid is obtained, keep at 1300℃ for 30 minutes, and at the same time turn on electromagnetic stirring.
[0049] Step S3, blank preparation: Add yttrium oxide to the alloy liquid, stir evenly, and then introduce the liquid into an inert gas atomization device to obtain fine spherical powder. The powder is sieved with a sieve particle size of 100 mesh, sieved and packed into a sleeve, vacuum sealed, and kept at 850℃ and 100MPa argon pressure for 4 hours to form a blank.
[0050] Step S4, solution treatment: The temperature of the blank is controlled at 900℃, held for 30 minutes and then rapidly quenched in water to obtain a supersaturated solid solution;
[0051] Step S5, cold working and intermediate annealing: The supersaturated solid solution is subjected to multi-pass cold rolling, with a single-pass cold rolling deformation of 15%-20%. After the single-pass cold rolling, the hardness is measured. When the hardness increase is less than 30%, an intermediate annealing is performed after two passes. When the hardness increase is greater than 30%, an intermediate annealing is performed after the single-pass cold rolling. The intermediate annealing temperature is 650℃ and the time is 15 minutes. The total processing deformation is 90%, and the initial target material is obtained.
[0052] Step S6, recrystallization annealing: The annealed initial target material is held at 700℃ for 2 hours to obtain a silver-palladium-copper alloy plate.
[0053] Step S7, finishing: The silver-palladium-copper alloy plate after recrystallization annealing is surface-machined to the required size and surface roughness to obtain the silver-palladium-copper alloy target; in this embodiment, the silver-palladium-copper alloy target is processed into a large-area rectangular planar target for use in large-size touch screen wiring.
[0054] Example 3
[0055] Preparation of a silver-palladium-copper alloy target material, wherein the target material comprises 2.0 wt% palladium, 3.0 wt% copper, 0.02 wt% cerium-based mixed rare earth elements, and the balance being silver;
[0056] The preparation of the target material includes the following steps:
[0057] Step S1, Material preparation: Weigh out palladium, copper and silver powder according to the weight composition of the silver-palladium-copper alloy target material, and set aside for use;
[0058] Step S2, Vacuum Melting: Turn on the vacuum induction melting device and evacuate to 1.0 × 10⁻⁶. -2 Pa, fill with high-purity argon to a slightly positive pressure; put metallic copper and metallic palladium into a magnesium oxide crucible, heat to 1150℃, when molten metal appears, add silver powder, heat to 1600℃ until the solid melts; after melting, the alloy liquid is obtained, and it is kept at 1400℃ for 15 minutes while the electromagnetic stirring is turned on.
[0059] Step S3, blank preparation: Add grain refiner to alloy liquid, stir evenly, and then introduce the liquid into inert gas atomization equipment to obtain fine spherical powder. The powder is sieved with a sieve particle size of 325 mesh, sieved and packed into a sleeve, vacuum sealed and welded, and kept at 950℃ and 150 MPa argon pressure for 2 hours to form blank.
[0060] Step S4, solution treatment: The temperature of the blank is controlled at 920℃, held for 45 minutes and then rapidly quenched in water to obtain a supersaturated solid solution;
[0061] Step S5, cold working and intermediate annealing: The supersaturated solid solution is subjected to multi-pass cold rolling, with a single-pass cold rolling deformation of 15%-18%. After the single-pass cold rolling is completed, the hardness is measured. When the hardness increase is less than 30%, an intermediate annealing is performed after two passes. When the hardness increase is greater than 30%, an intermediate annealing is performed after the single-pass cold rolling. The intermediate annealing temperature is 720℃ and the time is 25 minutes. The total processing deformation is 80%, and the initial target material is obtained.
[0062] Step S6, recrystallization annealing: The annealed initial target material is held at 780℃ for 45 minutes to obtain a silver-palladium-copper alloy plate;
[0063] Step S7, finishing: The silver-palladium-copper alloy plate after recrystallization annealing is surface-machined to the required size and surface roughness to obtain the silver-palladium-copper alloy target material; in this embodiment, the silver-palladium-copper alloy target material is processed into a high-precision circular planar target material for use as an electrode for optical disc reflective film or LED.
[0064] Example 4
[0065] The preparation of a silver-palladium-copper alloy target material is characterized in that the target material comprises 5.0 wt% palladium, 0.1 wt% copper, 0.03 wt% yttrium and 0.02 wt% mixed rare earth elements mainly composed of cerium, with the balance being silver.
[0066] The preparation of the target material includes the following steps:
[0067] Step S1, Material preparation: Weigh out palladium, copper and silver powder according to the weight composition of the silver-palladium-copper alloy target material, and set aside for use;
[0068] Step S2, Vacuum Melting: Turn on the vacuum induction melting device and evacuate to a vacuum level of 2.0 × 10⁻⁶. -2 Pa, fill with high-purity argon to a slightly positive pressure; put metallic copper and metallic palladium into a magnesium oxide crucible, heat to 1100℃, when molten metal appears, add silver powder, heat to 1550℃ until the solid melts completely, after melting, the alloy liquid is obtained, keep at 1350℃ for 20 minutes, and turn on electromagnetic stirring.
[0069] Step S3, blank preparation: Add yttrium and mixed rare earth elements to the alloy liquid, stir evenly, and then introduce the liquid into an inert gas atomization device to obtain fine spherical powder. The powder is sieved with a sieve particle size of 500 mesh, sieved and packed into a sleeve, vacuum sealed, and held at 900℃ and 125 MPa argon pressure for 3 hours to form a blank.
[0070] Step S4, solution treatment: control the temperature of the blank in the single-phase region, the temperature is 800℃, hold for 2 hours and then quickly water quench to obtain a supersaturated solid solution.
[0071] Step S5, cold working and intermediate annealing: The supersaturated solid solution is subjected to multi-pass cold rolling, with a single-pass cold rolling deformation of 15%-20%. After the single-pass cold rolling is completed, the hardness is measured. When the hardness increase is less than 30%, an intermediate annealing is performed after two passes. When the hardness increase is greater than 30%, an intermediate annealing is performed after the single-pass cold rolling. The intermediate annealing temperature is 750℃ and the time is 30 minutes. The total processing deformation is 85%, and the initial target material is obtained.
[0072] Step S6, recrystallization annealing: The annealed initial target material is held at 800℃ for 30 minutes to obtain a silver-palladium-copper alloy plate.
[0073] Step S7, finishing: The silver-palladium-copper alloy plate after recrystallization annealing is surface-machined to the required size and surface roughness to obtain the silver-palladium-copper alloy target; in this embodiment, the silver-palladium-copper alloy target is processed into a long strip rotating target, i.e., a columnar structure, and applied to LCD electrodes.
[0074] Example 5
[0075] The difference between this embodiment and Embodiment 1 is that a silver-palladium-copper alloy target material is prepared, wherein the target material comprises 0.5wt%-5.0wt% palladium, 0.1wt%-3.0wt% copper, and the balance is silver;
[0076] The preparation steps of the target material in this embodiment are the same as those in Example 1, and will not be repeated here.
[0077] Comparative Example
[0078] The difference between this comparative example and Example 1 is that the target material is pure silver, and it is prepared according to the process of Example 1; wherein, during step S2 vacuum melting, the vacuum induction melting device is turned on and the vacuum is drawn to 1.0 × 10⁻⁶. -2 Pa, after filling with high-purity argon gas to a slightly positive pressure, silver powder is added directly. The addition of grain refiner is omitted in step S3.
[0079] The performance of the target materials used in the above examples and comparative examples was measured, and the experimental results are as follows:
[0080]
[0081] Based on the comparison of the resistivity and reflectivity after film formation, the resistance value changes significantly depending on the ratio of silver-palladium-copper alloy. For example, Example 2 has low resistance and low reflectivity, meeting the wiring requirements of touch screens; Example 3 has high reflectivity, meeting the requirements of optical disc reflective films. Comparing the examples and comparative examples, the silver-palladium-copper alloy with added grain refiner shows improved heat resistance, service life (reliability), and sulfidation resistance. Precisely adding specific amounts of palladium, copper, and grain refiner to the silver-based alloy improves the alloy's mechanical strength, corrosion resistance, and high-temperature oxidation resistance while maintaining the excellent electrical and thermal conductivity of silver. Simultaneously, grain refinement helps improve subsequent processing performance and enhances the uniformity of the target material's microstructure.
[0082] Based on the above-described preferred embodiments of the present invention, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the technical concept of this invention. The technical scope of this invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.
Claims
1. A method for preparing a silver-palladium-copper alloy target material, characterized in that, The target material comprises 0.5wt%-5.0wt% palladium, 0.1wt%-3.0wt% copper, 0.01wt%-0.05wt% grain refiner, and the balance being silver; the preparation of the target material includes the following steps: Step S1, Material preparation: Weigh out palladium, copper and silver powder according to the weight composition of the silver-palladium-copper alloy target material, and set aside for use; Step S2, Vacuum Melting: Turn on the vacuum induction melting device, evacuate, and fill with high-purity argon gas to a slightly positive pressure; put metallic copper and metallic palladium into a crucible, heat until molten metal appears, add silver powder, and heat until the solid melts completely; after melting, an alloy liquid is obtained, and it is kept at 1300℃-1400℃ for a period of time, and the electromagnetic stirring is turned on. Step S3, blank preparation: Add grain refiner to alloy liquid, stir evenly, and then introduce the liquid into inert gas atomization equipment to obtain fine spherical powder. After the powder is sieved, it is packed into a sleeve, vacuum sealed, and kept warm and pressured to form a blank. Step S4, solution treatment: control the temperature of the blank in the single-phase region, hold it at that temperature for a certain time, and then quickly quench it in water to obtain a supersaturated solid solution. Step S5, cold working and intermediate annealing: The supersaturated solid solution is cold rolled in multiple passes, and after single or double cold rolling, an intermediate annealing is performed. The total processing deformation is 80%-90% to obtain the initial target material. Step S6, recrystallization annealing: The annealed initial target material is held at 700℃-800℃ to obtain a silver-palladium-copper alloy plate. Step S7, finishing: The silver-palladium-copper alloy plate after recrystallization annealing is surface-finished to the required size and surface roughness to obtain the silver-palladium-copper alloy target.
2. The preparation of a silver-palladium-copper alloy target material according to claim 1, characterized in that: In step S2, during vacuum melting, the vacuum is evacuated to 1.0 × 10⁻⁶. -2 Pa-5.0×10 -2 Pa; the temperature before adding silver powder is 1050℃-1150℃, and the temperature after adding silver powder is 1500℃-1600℃; after melting and clearing, the alloy liquid is cooled to the holding temperature and held at the holding temperature for 15 minutes-30 minutes; the crucible is a magnesium oxide crucible or a graphite crucible.
3. The preparation of a silver-palladium-copper alloy target material according to claim 1, characterized in that: The grain refiner is one or more of yttrium, yttrium oxide, and rare earth metals.
4. The preparation of a silver-palladium-copper alloy target material according to claim 1, characterized in that: In step S3, the particle size of the powder sieve used for raw material preparation is 100-500 mesh; the temperature for heat preservation and pressure holding after vacuum sealing is 850℃-950℃, the pressure is 100MPa-150MPa argon pressure, and the heat preservation and pressure holding time is 2-4 hours.
5. The preparation of a silver-palladium-copper alloy target material according to claim 1, characterized in that: In step S4, the solution treatment temperature in the single-phase region is 800-950℃, and the holding time is 30 minutes to 2 hours.
6. The preparation of a silver-palladium-copper alloy target material according to claim 1, characterized in that: In step S5, the cold rolling deformation per pass during cold working and annealing is 15%-30%; the intermediate annealing temperature is 650℃-750℃, and the time is 15 minutes-30 minutes.
7. The preparation of a silver-palladium-copper alloy target material according to claim 1, characterized in that: In step S5, cold working and annealing, hardness is measured after a single pass of cold rolling. If the hardness increase is less than 30%, an intermediate annealing is performed after two passes. If the hardness increase is greater than 30%, an intermediate annealing is performed after a single pass of cold rolling.
8. The preparation of a silver-palladium-copper alloy target material according to claim 1, characterized in that: During the recrystallization annealing in step S6, the temperature is maintained for 30 minutes to 2 hours.
9. The preparation of a silver-palladium-copper alloy target material according to claim 1, characterized in that: The silver-palladium-copper alloy target material has a square structure, a circular structure, a columnar structure, or an irregular structure.
10. The application of a silver-palladium-copper alloy target material according to any one of claims 1-9, characterized in that: The silver-palladium-copper alloy target is used for reflective films in optical discs, electrodes for LCDs, OLEDs, and LEDs, and wiring materials for touch screens.