5052 aluminum alloy cavity for semiconductor device and method of manufacturing the same

Abstract

This invention discloses a 5052 aluminum alloy cavity for semiconductor devices and its preparation method, relating to the field of aluminum alloy material technology. Specifically, it includes the following steps: S1: First, the 5052 aluminum alloy ingot undergoes a two-stage homogenization treatment, followed by a three-stage free forging process, and finally, spray cooling and air drying to obtain a shaped cavity substrate; S2: After plasma cleaning, the shaped cavity substrate is subjected to magnetron sputtering technology to sequentially deposit a transition layer, a barrier layer, and a functional layer on its inner surface to obtain the 5052 aluminum alloy cavity for semiconductor devices. The 5052 aluminum alloy cavity prepared by this invention can greatly ensure the stability and purity of the prepared aerospace semiconductors, meeting the manufacturing needs of high-performance chips for aerospace applications, and is of great significance.

Description

Technical Field

[0001] This invention relates to the field of aluminum alloy materials technology, specifically to a 5052 aluminum alloy cavity for semiconductor devices and its preparation method. Background Technology

[0002] With the rapid development of the aerospace field, the demand for high-performance aerospace semiconductor devices such as chips and semiconductor components is increasing. As the core carrier for reaction, etching and deposition in the semiconductor device manufacturing process, the performance of the semiconductor cavity directly determines the manufacturing accuracy, stability and service life of the semiconductor device, and has a crucial impact on the reliability of aerospace equipment.

[0003] Currently, semiconductor device cavities are mostly made of aluminum alloys. Among them, 5052 aluminum alloy has become one of the preferred materials for aerospace semiconductor cavities due to its advantages such as low density, high specific strength, and good corrosion resistance. However, there are still many technical bottlenecks in its actual manufacturing and application, making it difficult to meet the extreme operating conditions required in the aerospace field. For example, traditional 5052 aluminum alloy cavities are prone to residual stress due to excessively fast or uneven cooling rates, which can lead to cavity deformation. This can also result in excessively large grain sizes in the cavity, causing obvious defects on the cavity surface and greatly affecting the quality of the semiconductor.

[0004] Based on this, the present invention provides a 5052 aluminum alloy cavity for semiconductor devices and its preparation method, which is of great significance. Summary of the Invention

[0005] The purpose of this invention is to provide a 5052 aluminum alloy cavity for semiconductor devices and a method for preparing the same, so as to solve the problems mentioned in the background art.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution: A method for fabricating a 5052 aluminum alloy cavity for a semiconductor device includes the following steps: S1: Forging process: First, the 5052 aluminum alloy ingot is subjected to two-stage homogenization treatment, then three-stage free forging process, and finally spray cooling treatment and air drying to obtain the forming cavity matrix. S2: Surface treatment: After plasma cleaning, the molded cavity substrate is deposited with a transition layer, a barrier layer and a functional layer in sequence on its inner surface by magnetron sputtering technology to obtain a 5052 aluminum alloy cavity for semiconductor devices.

[0007] Further, the specific process of the two-stage homogenization treatment is as follows: (1) Place the 5052 aluminum alloy ingot into a closed heating furnace and heat it to 395~405℃ at a heating rate of 15~25℃ / h and hold it for 4~6h to complete the first-stage homogenization treatment; (2) After the first-stage homogenization treatment, continue to heat it to 520~530℃ at a heating rate of 5~10℃ / h and hold it for 18~30h to complete the second-stage homogenization treatment.

[0008] Furthermore, the three-stage free forging process includes three steps: upsetting, drawing, and hole expansion. The specific process is as follows: (1) After two-stage homogenization, the 5052 aluminum alloy ingot is cooled to the upsetting temperature at a cooling rate of 5~10℃ / h, and then placed on a 2~5mm thick Al2O3 ceramic fiber pad laid on the hydraulic press workbench for upsetting; (2) After upsetting, the temperature is further reduced to the drawing temperature at a cooling rate of 5~10℃ / h, and the drawing is performed using a double conical anvil; (3) After drawing, the temperature is further reduced to the hole expansion temperature at a cooling rate of 5~10℃ / h, and the hole is expanded using a mandrel coated with 5~8μm thick BN to complete the three-stage free forging process.

[0009] Furthermore, the upsetting process parameters are as follows: upsetting temperature is 425~435℃, reduction is 25~35%, and upsetting speed is 20~30mm / s; the drawing parameters are as follows: drawing temperature is 395~405℃, feed ratio is 0.6~0.7, and the angle of each flip is 120°; the reaming parameters are as follows: reaming temperature is 375~385℃, mandrel speed is 3~7r / min, and radial feed is 0.2~0.4mm / rev.

[0010] Furthermore, the process parameters for the spray cooling are as follows: nitrogen is used as the working gas, the working pressure is 0.55~0.65MPa; the water pressure is 0.3~0.4MPa, the nozzle angle is 60°, and the spray distance is 130~170mm.

[0011] Furthermore, the spray cooling process is divided into two cooling stages: the first cooling stage cools the temperature after molding to 290~310℃ at a cooling rate of 8~10℃ / s; the second cooling stage cools the temperature from 290~310℃ to 80~100℃ at a cooling rate of 3~4℃ / s.

[0012] Furthermore, the air drying process involves using compressed air to force-dry the molding cavity when it cools to 80-100°C.

[0013] Furthermore, the process parameters for plasma cleaning are as follows: argon is used as the working gas, the working pressure is 1~2Pa, the cleaning power is 0.5~1kW, the bias voltage is -100~-140V, and the cleaning time is 15~30min.

[0014] Furthermore, the transition layer is a Cr-CrN transition layer, which consists of a Cr layer with a thickness of 50~100nm that directly contacts the inner surface of the molding cavity substrate and a CrN layer with a thickness of 50~100nm.

[0015] Furthermore, the Cr layer is deposited by DC magnetron sputtering technology with the following sputtering parameters: the target material is high-purity Cr, argon is used as the working gas with a flow rate of 30~50 sccm, the working pressure is 0.5~3 Pa, the sputtering power is 0.5~2 kW, the bias voltage is -50~-80 V, the target-substrate distance is 50~100 mm, and the sputtering temperature is 150~200 °C.

[0016] Furthermore, the CrN layer is deposited by DC magnetron sputtering technology. The sputtering parameters are as follows: the target material is high-purity Cr, the working gas is an argon / nitrogen mixed gas with a mixing ratio of (5~8):(2~5), the gas flow rate is 30~50 sccm, the working pressure is 0.5~3 Pa, the sputtering power is 0.5~2 kW, the bias voltage is -80~-120 V, the target-substrate distance is 50~100 mm, and the sputtering temperature is 150~200 °C.

[0017] Furthermore, the barrier layer is an AlN layer with a thickness of 1~2μm.

[0018] Furthermore, the AlN layer is deposited by radio frequency magnetron sputtering technology. The sputtering parameters are as follows: the target material is a high-purity AlN target, the working gas is an argon / nitrogen mixed gas with a mixing ratio of (8~9):(1~2), the gas flow rate is 30~50 sccm, the working pressure is 0.5~3 Pa, the sputtering power is 0.5~2 kW, the bias voltage is -120~-150 V, the radio frequency is 13.56 MHz, the target-substrate distance is 50~100 mm, and the sputtering temperature is 150~200 °C.

[0019] Furthermore, the functional layer is an AlN-SiC composite layer with a thickness of 1~2μm.

[0020] Furthermore, the AlN-SiC composite layer is deposited by radio frequency magnetron sputtering technology. The sputtering parameters are as follows: the target material is a high-purity AlN target and a high-purity SiC target; an argon / nitrogen mixed gas is used as the working gas, with an argon to nitrogen mixing ratio of (8~9):(1~2); the gas flow rate is 30~50 sccm; the working pressure is 0.5~3 Pa; the sputtering power of the AlN target is 0.8~1.5 kW; the sputtering power of the SiC target is 0.5~1 kW; the bias voltage is -150~-200 V; the radio frequency is 13.56 MHz; the target-substrate distance is 50~100 mm; and the sputtering temperature is 150~200 °C.

[0021] Compared with the prior art, the beneficial effects achieved by the present invention are: (1) In this invention, the 5052 aluminum alloy ingot is subjected to two-stage homogenization treatment. The first-stage homogenization treatment is carried out at a relatively low temperature of 395~405℃. Its purpose is to eliminate the microsegregation in the 5052 aluminum alloy ingot and avoid introducing structural defects by directly homogenizing at high temperature. The second-stage homogenization treatment is carried out at 520~530℃, which is the solid solution temperature of 5052 aluminum alloy. Its purpose is to thoroughly remove the macro and micro segregation in the 5052 aluminum alloy ingot, thereby achieving full dissolution of the Mg2Al3 phase in the 5052 aluminum alloy ingot, so as to obtain a saturated solid solution and obtain an aluminum alloy with better plasticity and forging performance, laying a solid foundation for subsequent forging.

[0022] (2) In this invention, a three-stage free forging process is further adopted. Through specific process parameters, the material structure is effectively improved by coordinating two-stage homogenization processes, thereby enhancing the mechanical properties of the cavity.

[0023] (3) In this invention, segmented spray cooling is used to control the cooling rate. The rapid cooling in the first stage can suppress the growth of recrystallized grains, and the slow cooling in the second stage can eliminate stress, thereby significantly reducing the grain size in the cavity, reducing the internal stress of the cavity, preventing its deformation, and improving the dimensional stability and molding accuracy of the cavity.

[0024] (4) In this invention, a transition layer (Cr layer + CrN layer), a barrier layer (AlN layer), and a functional layer (AlN-SiC composite layer) are sequentially deposited on the inner surface of the molded cavity. Through the design of the transition layer, barrier layer, and functional layer, the layers are tightly bonded together, which greatly ensures the bonding force between the 5052 aluminum alloy cavity and the film layer. Among them, the Cr layer can effectively enhance the bonding strength between the film and the substrate and relieve the interfacial stress; the CrN layer can realize the gradient transition from metal to ceramic and improve the plasma corrosion resistance of the 5052 aluminum alloy cavity; the AlN layer can play an excellent role in blocking element diffusion, which can prevent the aluminum alloy matrix elements from diffusing outward and prevent the corrosive medium from penetrating the matrix, which greatly ensures the stability of the 5052 aluminum alloy cavity and thus ensures the quality of the semiconductor; the AlN-SiC composite layer can give the 5052 aluminum alloy cavity surface high hardness, low roughness, high wear resistance and excellent plasma corrosion resistance.

[0025] (5) The 5052 aluminum alloy cavity prepared by the present invention can greatly ensure the stability and purity of the prepared aerospace semiconductor, and can meet the manufacturing needs of high-performance chips for aerospace, which is of great significance. Detailed Implementation

[0026] The technical solutions in the embodiments of the present invention are clearly and completely described below. Obviously, the embodiments described are only some, not all, implementations of the present invention. Other implementations that can be obtained by those skilled in the art based on the embodiments of the present invention without creative effort all fall within the protection scope of the present invention.

[0027] It should be noted that the following quantities are by weight. There are no special restrictions on the manufacturers of the raw materials involved in this invention. Exemplary examples include: 5052-O state aluminum alloy ingots; Cr, CrN, AlN, and SiC with a purity of 99.99%; and other raw materials, all of which are commercially available.

[0028] Example 1: A method for fabricating a 5052 aluminum alloy cavity for semiconductor devices: S1: Forging process: S11: Two-stage homogenization treatment: (1) Place the 5052 aluminum alloy ingot into a closed heating furnace and heat it to 400℃ at a heating rate of 20℃ / h and hold it for 5h to complete the first-stage homogenization treatment; (2) After the first-stage homogenization treatment, continue to heat it to 525℃ at a heating rate of 7.5℃ / h and hold it for 24h to complete the second-stage homogenization treatment. S12: Three-stage free forging process: (1) After two-stage homogenization, the 5052 aluminum alloy ingot is cooled to 430°C at a cooling rate of 7.5°C / h, and then placed on a 3mm thick Al2O3 ceramic fiber pad laid on the hydraulic press workbench. Upsetting is performed with a reduction of 30% and an upsetting rate of 25mm / s. (2) After upsetting, the temperature is further reduced to 400°C at a cooling rate of 7.5°C / h. A double-cone anvil is used, and the lengthening process is performed with a feed ratio of 0.65 and a turning angle of 120° each time. (3) After lengthening, the temperature is further reduced to 380°C at a cooling rate of 7.5°C / h. A mandrel coated with 6.5μm thick BN is used, and the hole is enlarged with a mandrel speed of 5r / min and a radial feed of 0.3mm / rev. The three-stage free forging process is completed. S13: Spray Cooling Treatment + Air Drying: After the three-stage free forging process, the formed workpiece is transferred to the spray cooling station. Nitrogen is used as the working gas, with a working pressure of 0.6MPa, a water pressure of 0.35MPa, 8 sets of fan-shaped nozzles set at a 60° angle, and a spray distance of 150mm for spray cooling treatment. The spray cooling treatment is divided into two stages. The first cooling stage cools the workpiece from the formed temperature to 300℃ at a cooling rate of 10℃ / s. The second cooling stage cools the workpiece from 300℃ to 80℃ at a cooling rate of 4℃ / s. 80℃ is used as the final cooling temperature. Subsequently, compressed air is used for forced air drying to obtain the formed cavity substrate. S2: Surface treatment: S21: Plasma cleaning: Argon is used as the working gas, and the substrate of the molding cavity is subjected to plasma cleaning treatment for 20 minutes with process parameters of working pressure 1.5Pa, cleaning power 0.75kW, and bias voltage -120V. S22: Deposition transition layer: (1) Using DC magnetron sputtering technology, high-purity Cr is used as the target material, argon is used as the working gas, and the process parameters are 40 sccm gas flow rate, 2 Pa working pressure, 1.5 kW sputtering power, -65 V bias voltage, 80 mm target-substrate distance and 175 °C sputtering temperature to deposit a 75 nm thick Cr layer on the inner surface of the substrate cavity of the forming cavity. (2) A 75nm thick CrN layer was sputtered on the Cr layer using DC magnetron sputtering technology, with high-purity Cr as the target material and argon / nitrogen mixed gas as the working gas. The mixing ratio of argon and nitrogen was 7:3. The process parameters were 40sccm gas flow rate, 2Pa working pressure, 1.5kW sputtering power, -100V bias voltage, 80mm target-substrate distance, and 175℃ sputtering temperature. S23: Deposition of barrier layer: Using radio frequency magnetron sputtering technology, high-purity AlN is used as the target material, and an argon / nitrogen mixed gas is used as the working gas. The mixing ratio of argon and nitrogen is 8:2, the gas flow rate is 40 sccm, the working pressure is 2 Pa, the sputtering power is 1 kW, the bias voltage is -135 V, the radio frequency is 13.56 MHz, the target-substrate distance is 80 mm, and the sputtering temperature is 175 ℃. A 1.5 μm thick AlN layer is sputtered and deposited on the transition layer. S24: Deposition of functional layer: Using radio frequency magnetron sputtering technology, high-purity AlN and high-purity SiC are used as targets, and an argon / nitrogen mixed gas is used as the working gas. The argon to nitrogen mixing ratio is 8:2, the gas flow rate is 40 sccm, the working pressure is 2 Pa, the sputtering power is 1 kW, the bias voltage is -175 V, the radio frequency is 13.56 MHz, the target-substrate distance is 80 mm, and the sputtering temperature is 175 ℃. A 1.5 μm thick AlN-SiC composite layer is sputtered and deposited on the barrier layer to obtain a 5052 aluminum alloy cavity for semiconductor devices with an outer diameter of 200 mm, a wall thickness of 10 mm, and a height of 300 mm.

[0029] The following control experiments were conducted based on Example 1, with comparative examples 1 to 9, as detailed below: Comparative Example 1: A method for fabricating a 5052 aluminum alloy cavity for a semiconductor device: Comparative Example 1 is based on Example 1, with the following adjustment: only one homogenization treatment is performed, while other processes remain unchanged. Specifically: S11: Homogenization treatment: (1) Place the 5052 aluminum alloy ingot into a closed heating furnace and continue heating to 525℃ at a heating rate of 7.5℃ / h and hold for 24h to complete the homogenization treatment.

[0030] Comparative Example 2: A method for fabricating a 5052 aluminum alloy cavity for a semiconductor device: Comparative Example 2 is based on Example 1, with the following adjustment: the spray cooling stage is reduced to a single cooling stage, while other processes remain unchanged. Specifically: S13: Spray cooling treatment + air drying: After the three-stage free forging process, the formed workpiece is transferred to the spray cooling station. Nitrogen is used as the working gas, and the process parameters are 0.6MPa working pressure, 0.35MPa water pressure, 8 sets of fan-shaped nozzles set at a 60° angle, and a spray distance of 150mm for spray cooling treatment. The cooling rate is 10℃ / s, and 80℃ is used as the final cooling temperature. Subsequently, compressed air is used for forced air drying to obtain the formed cavity matrix.

[0031] Comparative Example 3: A method for fabricating a 5052 aluminum alloy cavity for a semiconductor device: Comparative Example 3 is based on Example 1, with the following adjustment: no Cr layer is deposited, while other processes remain unchanged. Specifically: S22: Deposition of transition layer: A 75nm thick CrN layer is deposited on the inner surface of the substrate cavity using DC magnetron sputtering technology, with high-purity Cr as the target material and argon / nitrogen mixed gas as the working gas. The argon to nitrogen mixing ratio is 7:3. The process parameters are as follows: gas flow rate 40sccm, working pressure 2Pa, sputtering power 1.5kW, bias voltage -100V, target-substrate distance 80mm, and sputtering temperature 175℃.

[0032] Comparative Example 4: A method for fabricating a 5052 aluminum alloy cavity for a semiconductor device: Comparative Example 4 is based on Example 1, with the following adjustment: no CrN layer is deposited, while other processes remain unchanged. Specifically: S22: Deposition of transition layer: Using DC magnetron sputtering technology, high-purity Cr is used as the target material, argon is used as the working gas, and the process parameters are as follows: gas flow rate 40 sccm, working pressure 2 Pa, sputtering power 1.5 kW, bias voltage -65 V, target-substrate distance 80 mm, sputtering temperature 175 ℃. A 75 nm thick Cr layer (transition layer) is sputtered and deposited on the inner surface of the substrate in the forming cavity.

[0033] Comparative Example 5: A method for fabricating a 5052 aluminum alloy cavity for a semiconductor device: Comparative Example 5 is based on Example 1, with the following adjustment: no transition layer is deposited, while other processes remain unchanged. Specifically: S22: Deposition of barrier layer: Using radio frequency magnetron sputtering technology, high-purity AlN is used as the target material, and an argon / nitrogen mixed gas is used as the working gas. The mixing ratio of argon and nitrogen is 8:2, the gas flow rate is 40 sccm, the working pressure is 2 Pa, the sputtering power is 1 kW, the bias voltage is -135 V, the radio frequency is 13.56 MHz, the target-substrate distance is 80 mm, and the sputtering temperature is 175 ℃. A 1.5 μm thick AlN layer is sputtered and deposited on the inner surface of the substrate cavity of the forming cavity.

[0034] Comparative Example 6: A method for fabricating a 5052 aluminum alloy cavity for a semiconductor device: Comparative Example 6 is based on Example 1, with the following adjustment: no barrier layer is deposited, while other processes remain unchanged. Specifically: S23: Deposition of functional layer: Using radio frequency magnetron sputtering technology, high-purity AlN and high-purity SiC are used as targets, and an argon / nitrogen mixed gas is used as the working gas. The argon to nitrogen mixing ratio is 8:2, the gas flow rate is 40 sccm, the working pressure is 2 Pa, the sputtering power is 1 kW, the bias voltage is -175 V, the radio frequency is 13.56 MHz, the target-substrate distance is 80 mm, and the sputtering temperature is 175 ℃. A 1.5 μm thick AlN-SiC composite layer is sputtered and deposited on the transition layer to obtain a 5052 aluminum alloy cavity for semiconductor devices with an outer diameter of 200 mm, a wall thickness of 10 mm, and a height of 300 mm.

[0035] Comparative Example 7: A method for fabricating a 5052 aluminum alloy cavity for a semiconductor device: Comparative Example 7 is based on Example 1, with the following adjustment: no functional layer is deposited, while other processes remain unchanged. Specifically: S23: Deposition of barrier layer: Using radio frequency magnetron sputtering technology, high-purity AlN is used as the target material, and an argon / nitrogen mixed gas is used as the working gas. The mixing ratio of argon and nitrogen is 8:2, the gas flow rate is 40 sccm, the working pressure is 2 Pa, the sputtering power is 1 kW, the bias voltage is -135 V, the radio frequency is 13.56 MHz, the target-substrate distance is 80 mm, and the sputtering temperature is 175 ℃. A 1.5 μm thick AlN layer is sputtered and deposited on the transition layer to obtain a 5052 aluminum alloy cavity for semiconductor devices with an outer diameter of 200 mm, a wall thickness of 10 mm, and a height of 300 mm.

[0036] Comparative Example 8: A method for fabricating a 5052 aluminum alloy cavity for a semiconductor device: Comparative Example 8 is based on Example 1, with the following adjustment: direct deposition of the functional layer, while other processes remain unchanged. Specifically: S24: Deposition of Functional Layer: Using radio frequency magnetron sputtering technology, high-purity AlN and high-purity SiC are used as targets, and an argon / nitrogen mixed gas is used as the working gas. The argon to nitrogen mixing ratio is 8:2, the gas flow rate is 40 sccm, the working pressure is 2 Pa, the sputtering power is 1 kW, the bias voltage is -175 V, the radio frequency is 13.56 MHz, the target-substrate distance is 80 mm, and the sputtering temperature is 175 ℃. A 1.5 μm thick AlN-SiC composite layer is sputtered and deposited on the inner surface of the forming cavity substrate to obtain a 5052 aluminum alloy cavity for semiconductor devices with an outer diameter of 200 mm, a wall thickness of 10 mm, and a height of 300 mm.

[0037] Comparative Example 9: A method for fabricating a 5052 aluminum alloy cavity for a semiconductor device: Comparative Example 9 is based on Example 1, with the following adjustment: no surface treatment is performed, while other processes remain unchanged. Specifically: S13: Spray Cooling + Air Drying: After three-stage free forging, the formed workpiece is transferred to the spray cooling station. Nitrogen is used as the working gas, and the process parameters are as follows: working pressure 0.6MPa, water pressure 0.35MPa, 8 sets of fan-shaped nozzles set at a 60° angle, and spray distance 150mm. The spray cooling process is divided into two stages. The first cooling stage cools from the formed temperature to 300℃ at a cooling rate of 10℃ / s. The second cooling stage cools from 300℃ to 80℃ at a cooling rate of 4℃ / s. 80℃ is used as the final cooling temperature. Subsequently, compressed air is used for forced air drying to obtain a 5052 aluminum alloy cavity for semiconductor equipment with an outer diameter of 200mm, a wall thickness of 10mm, and a height of 300mm.

[0038] Performance testing: The following performance tests were performed on the 5052 aluminum alloy cavities for semiconductor devices prepared in Example 1 and Comparative Examples 1-9: (1) Film adhesion: The film adhesion of the inner surface of the 5052 aluminum alloy cavity for semiconductor equipment was tested according to the test method in ASTM C1624. The scratching speed was 10 mm / min. (2) Surface roughness: The surface roughness of the inner surface of the 5052 aluminum alloy cavity for semiconductor equipment was tested using an HDX-ZYGO white light interferometer; (3) Plasma etching rate: An inductively coupled plasma etching machine was used, with a mixture of Ar, CF4 and O2 as the working gas. The mixing ratio of Ar, CF4 and O2 was 5:4:1. The working parameters were 2kW and 2Pa. The inner surface of the 5052 aluminum alloy cavity of the semiconductor equipment was plasma etched for 4 hours. Finally, the thickness of the film before and after etching was tested by a step meter. The plasma etching rate was calculated by the formula: Difference in film thickness before and after etching / Etching time = Etching rate.

[0039] (4) Wear resistance: The inner surface of the cavity of the 5052 aluminum alloy cavity for semiconductor equipment was subjected to a rotary wear test using an MZF-01 rotary reciprocating wear tester; the friction pair was an Al2O3 ceramic pair of balls (φ6mm, Ra<0.05μm), the test load was 20N, the rotation speed was 100r / min, the rotation torque was 2Nm, and the wear time was 20min; then, a plasma corrosion test was performed on it. (5) Grain size detection: The grain size of the 5052 aluminum alloy cavity used in semiconductor equipment is detected.

[0040] The specific test results are shown in Table 1 below: Table 1

[0041] Results Analysis: As shown in Table 1 above, this invention, through forging treatment (two-stage homogenization treatment + three-stage free forging treatment + two-stage spray cooling) + surface treatment (transition layer + barrier layer + functional layer), comprehensively prepares a semiconductor 5052 aluminum alloy cavity with refined grains, tight film bonding, low surface roughness, and excellent resistance to plasma corrosion and wear. This can greatly ensure the stability and purity of the prepared semiconductor, meet the manufacturing needs of high-performance chips for aerospace, and is of great significance.

[0042] It will be apparent to those skilled in the art that the present invention is not limited to the specific details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit and core features of the invention. Therefore, the above embodiments should be considered exemplary rather than restrictive in any respect. The scope of protection of the present invention is defined by the appended claims, not by the foregoing description, and is therefore intended to encompass all variations in the meaning and scope of the equivalents of the claims within the scope of the present invention.

Claims

1. A method of making a 5052 aluminum alloy cavity for semiconductor equipment, characterized by: Includes the following steps: S1: First, the 5052 aluminum alloy ingot is subjected to two-stage homogenization treatment, then three-stage free forging treatment, and finally spray cooling treatment and air drying to obtain the forming cavity matrix. S2: After plasma cleaning, the molded cavity substrate is subjected to magnetron sputtering technology to sequentially deposit a transition layer, a barrier layer, and a functional layer on its inner surface to obtain a 5052 aluminum alloy cavity for semiconductor devices. The specific process of the two-stage homogenization treatment is as follows: the 5052 aluminum alloy ingot is heated to 395~405℃ at a heating rate of 15~25℃ / h and held for 4~6h; then the temperature is further increased to 520~530℃ at a heating rate of 5~10℃ / h and held for 18~30h.

2. The method of claim 1, wherein the 5052 aluminum alloy cavity for semiconductor devices is prepared by the steps of: The three-stage free forging process includes three steps: upsetting, drawing, and hole expansion. The specific process is as follows: (1) After two-stage homogenization, the 5052 aluminum alloy ingot is cooled to the upsetting temperature at a cooling rate of 5~10℃ / h, and then placed on a 2~5mm thick ceramic fiber pad laid on the hydraulic press workbench for upsetting; (2) After upsetting, the temperature is further reduced to the drawing temperature at a cooling rate of 5~10℃ / h, and the drawing is performed using a double conical anvil; (3) After drawing, the temperature is further reduced to the hole expansion temperature at a cooling rate of 5~10℃ / h, and the hole is expanded using a mandrel coated with 5~8μm thick BN. ​ 3. The method of claim 2, wherein the 5052 aluminum alloy cavity for semiconductor devices is prepared by the steps of: The upsetting process parameters are: upsetting temperature of 425~435℃, reduction of 25~35%, and upsetting speed of 20~30mm / s; ​ The elongation operating parameters are: elongation temperature of 395~405℃, feed ratio of 0.6~0.7, and rotation angle of 120° each time; The working parameters for hole enlargement are: enlargement temperature of 375~385℃, spindle speed of 3~7r / min, and radial feed of 0.2~0.4mm / rev.

4. The method for preparing a 5052 aluminum alloy cavity for a semiconductor device according to claim 3, characterized in that: The process parameters for the spray cooling are as follows: nitrogen is used as the working gas, the working pressure is 0.55~0.65MPa, the water pressure is 0.3~0.4MPa, the nozzle angle is 60°, and the spray distance is 130~170mm.

5. The method for preparing a 5052 aluminum alloy cavity for a semiconductor device according to claim 4, characterized in that: The spray cooling process is divided into two cooling stages: the first cooling stage cools the temperature after molding to 290~310℃ at a cooling rate of 8~10℃ / s; the second cooling stage cools the temperature from 290~310℃ to 80~100℃ at a cooling rate of 3~4℃ / s.

6. The method for preparing a 5052 aluminum alloy cavity for a semiconductor device according to claim 1, characterized in that: The transition layer is a Cr-CrN transition layer, which consists of a Cr layer with a thickness of 50~100nm that directly contacts the inner surface of the molding cavity substrate and a CrN layer with a thickness of 50~100nm. The barrier layer is an AlN layer with a thickness of 1~2μm; The functional layer is an AlN-SiC composite layer with a thickness of 1~2μm.

7. The method for preparing a 5052 aluminum alloy cavity for a semiconductor device according to claim 6, characterized in that: The Cr layer was deposited by DC magnetron sputtering technology. The sputtering parameters were as follows: the target material was high-purity Cr, argon was used as the working gas, the gas flow rate was 30~50 sccm, the working pressure was 0.5~3 Pa, the sputtering power was 0.5~2 kW, the bias voltage was -50~-80 V, the target-substrate distance was 50~100 mm, and the sputtering temperature was 150~200℃. The CrN layer was deposited by DC magnetron sputtering. The sputtering parameters were as follows: the target material was high-purity Cr, the working gas was an argon / nitrogen mixture with a mixing ratio of (5~8):(2~5), the gas flow rate was 30~50 sccm, the working pressure was 0.5~3 Pa, the sputtering power was 0.5~2 kW, the bias voltage was -80~-120 V, the target-substrate distance was 50~100 mm, and the sputtering temperature was 150~200 °C. The AlN layer was deposited by radio frequency magnetron sputtering technology. The sputtering parameters were as follows: the target material was a high-purity AlN target, the working gas was an argon / nitrogen mixed gas with a mixing ratio of (8~9):(1~2), the gas flow rate was 30~50 sccm, the working pressure was 0.5~3 Pa, the sputtering power was 0.5~2 kW, the bias voltage was -120~-150 V, the radio frequency was 13.56 MHz, the target-substrate distance was 50~100 mm, and the sputtering temperature was 150~200 °C. The AlN-SiC composite layer was deposited by radio frequency magnetron sputtering technology. The sputtering parameters were as follows: the target materials were high-purity AlN target and high-purity SiC target; argon / nitrogen mixed gas was used as the working gas, with an argon to nitrogen mixing ratio of (8~9):(1~2); the gas flow rate was 30~50 sccm; the working pressure was 0.5~3 Pa; the sputtering power of the AlN target was 0.8~1.5 kW; the sputtering power of the SiC target was 0.5~1 kW; the bias voltage was -150~-200 V; the radio frequency was 13.56 MHz; the target-substrate distance was 50~100 mm; and the sputtering temperature was 150~200 °C.

8. A 5052 aluminum alloy cavity for semiconductor devices prepared by any one of claims 1 to 7.

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