Preparation method of high-purity super-thick 6061 aluminum alloy plate for semiconductor equipment

Abstract

The application relates to a preparation method of a high-purity super-thick 6061 aluminum alloy plate for semiconductor equipment, which comprises the following steps: step S1, batching; step S2, casting; step S3, homogenization heat treatment; step S4, cutting head and tail and surface; step S5, preheating; step S6, hot rolling; step S7, solid solution quenching; and step S8, artificial aging. The method optimizes the heat treatment process, ensures that the high-purity 6061 aluminum alloy has relatively uniform, moderate-size microstructure and high mechanical properties under the condition that the number of grain growth inhibiting elements is small, reduces the number of Fe-rich phases in the alloy under the design concept of low Fe, cooperates with high-temperature homogenization heat treatment, makes the Fe-rich phases as much as possible transform from coarse dendritic beta-AlFe phases into fine granular alpha-AlFe phases, reduces the size of the Fe-rich phases, and finally makes the high-purity 6061 aluminum alloy have excellent anodic oxidation performance and high mechanical properties, and meets the harsh requirements of semiconductor equipment on large-specification super-thick aluminum alloy.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of aluminum alloy plate processing, in particular to a preparation method of high-purity super-thick 6061 aluminum alloy plate for semiconductor equipment. BACKGROUND

[0002] The semiconductor equipment cavity (such as a transmission cavity, a reaction cavity and the like) is usually made of large-specification, high-purity and super-thick aluminum alloy products with a thickness of greater than or equal to 260 mm, and the large-specification, high-purity and super-thick aluminum alloy products with a thickness of greater than or equal to 260 mm are extremely difficult to manufacture. On the one hand, the thickness exceeds the upper limit of the allowable feeding thickness of a roller hearth furnace (the upper limit of the allowable plate thickness of the roller hearth furnace is usually less than 260 mm), so the advanced heat treatment furnace (roller hearth furnace) cannot be used for solid solution quenching, and the large pool quenching is prone to cause the great non-uniformity and instability of the microstructure and residual internal stress distribution of the plate surface and the core due to the unreasonable quenching process and the asynchronous cooling of the core and the surface of the material, thereby causing the obvious anodic oxidation color difference between the plate surface and the core, and causing the obvious difference in the corrosion resistance and electrical properties of the oxidation film. On the other hand, the large-specification, high-purity and super-thick 6061 aluminum alloy plate product usually needs to be prepared by using high-purity, super-thick and super-wide aluminum alloy ingots, and the casting technology of the high-purity, high-uniformity, super-thick and super-wide aluminum alloy ingot is extremely difficult. Generally speaking, the thicker the aluminum alloy ingot, the more serious the casting defects such as composition segregation, dendritic segregation and primary phase coarsening, so the large-specification super-thick 6061 aluminum alloy casting technology with high uniformity and high purity is still an industry problem at present.

[0003] At present, the large-specification, high-purity and super-thick 6061 aluminum alloy product for semiconductor equipment is rarely prepared by using the forging method, and the large-specification, high-purity and super-thick 6061 aluminum alloy product is not prepared by using the rolling method (at present, there is no related paper and patent publication of the aluminum alloy plate with a thickness of greater than or equal to 260 mm, and the thickness upper limit of GB / T 3880.2 is 250 mm). The 6061 aluminum alloy product prepared by using the forging method cannot meet the requirements of greater than or equal to 1500 mm in width and greater than or equal to 3000 mm in length when the thickness is greater than or equal to 260 mm due to the complexity of the forging technology and the limitation of the forging ratio, and cannot be applied to some large-specification semiconductor equipment. Compared with the forging method, the rolling method for preparing the 6061 aluminum alloy plate has the advantages of shorter process flow, more cost-effective cost and shorter delivery time, and has no limitation like the forging ratio, and is more suitable for preparing the large-specification super-thick 6061 aluminum alloy product.

[0004] The existing semiconductor-grade super-thick 6061 forging material (thickness greater than or equal to 260 mm) forging process is as follows:

[0005] Ingredients→Smelting→Composition Adjustment→Converter→Refining→On-line Degassing→Resting→Casting→Homogenization Treatment→Machining (milling, cutting head and tail, cutting forging blank)→Heating→First Forging→Heating→Second Forging→Heating→Third Forging→Solution Quenching (off-line quenching: heating furnace + large water pool)→Aging→Ultrasonic Flaw Detection→Vertical Sawing→Inspection→Packaging.

[0006] The 6061 aluminum alloy plate prepared by the prior art cannot meet the requirements of semiconductor equipment in specifications, anodic oxidation performance, etc., and has the following shortcomings or deficiencies: (1) the plate thickness is too thin, and the size specification requirements of thickness ≥ 260 mm and width > 1500 mm cannot be met at the same time; (2) there is obvious color difference in anodic oxidation, especially obvious anodic oxidation color difference in the thickness direction of the plate, and there are obvious differences in acid corrosion resistance and electric breakdown resistance of the oxidation film, which cannot meet the requirements at the same time; (3) the purity is low, the impurity phase and Fe-rich phase are coarse and numerous, and the combination with the matrix is not firm, which is easy to fall off during grinding and oxidation, resulting in poor compactness of the anodic oxidation film, poor corrosion resistance and low breakdown voltage.

[0007] Chinese patent CN101792877B discloses an aluminum alloy for semiconductor equipment and a preparation method thereof. The method mainly optimizes and controls the alloy composition, controls the contents of Cu, Mn, Mg and Si elements and the Mg / Si ratio to make the alloy have uniform microstructure and dispersed second phase, adopts electromagnetic casting process to obtain an aluminum alloy ingot with a specification of 150*400*400 mm, and then processes the ingot by forging to obtain an aluminum alloy forging material for semiconductor equipment. Obviously, the aluminum alloy obtained by this processing method cannot meet the requirements of semiconductor equipment for large-size aluminum alloy.

[0008] In order to overcome the shortcomings of the above-mentioned rolling and forging methods that cannot prepare large-size super-thick 6061 aluminum alloy products, the present application provides a large-size high-purity super-thick (thickness ≥ 260 mm) 6061 aluminum alloy plate for semiconductor equipment and a preparation method thereof, by reasonably adjusting the composition, smelting and casting process, homogenization heat treatment process, rolling process and heat treatment process. SUMMARY

[0009] In view of the deficiencies of the prior art, the purpose of the present application is to provide a preparation method of high-purity super-thick 6061 aluminum alloy plate for semiconductor equipment, which optimizes the heat treatment process, so that the high-purity 6061 aluminum alloy has a relatively uniform and appropriately sized microstructure and high mechanical properties under the condition of less grain growth inhibition elements; under the design concept of low Fe, the number of Fe-rich phases in the alloy has been reduced, and in combination with high-temperature homogenization heat treatment, the Fe-rich phases are converted from coarse dendritic β-AlFe phases to fine granular α-AlFe phases as much as possible, thereby reducing the size of the Fe-rich phases, and finally making the high-purity 6061 aluminum alloy have excellent anodic oxidation performance and high mechanical properties, thereby meeting the stringent requirements of semiconductor equipment on large-size super-thick aluminum alloy.

[0010] In order to achieve the above-mentioned purpose, the technical scheme adopted by the present application is as follows: a preparation method of high-purity super-thick 6061 aluminum alloy plate for semiconductor equipment, comprising the following steps:

[0011] Step S1, batching: the component composition and weight ratio of the high-purity super-thick 6061 aluminum alloy plate for semiconductor equipment are as follows: Si 0.56-0.64%, Fe≤0.12%, Cu 0.20-0.25%, Mn≤0.05%, Mg 0.9-1.1%, Cr 0.15-0.25%, Zn≤0.05%, Ti≤0.05%, and the rest is Al and some unavoidable impurity elements;

[0012] Step S2, casting: the component composition of the high-purity super-thick 6061 aluminum alloy plate for semiconductor equipment according to step S1 is batched, and then the high-purity super-thick 6061 aluminum alloy plate for semiconductor equipment is obtained through melting, composition adjustment, converter, online refining, filtering, and standing;

[0013] Step S3, homogenization heat treatment: the 6061 aluminum alloy slab obtained in step S2 is subjected to homogenization heat treatment, the homogenization temperature is 560-590℃, and the homogenization time is 18-30h, so as to obtain the homogenized 6061 aluminum alloy slab;

[0014] Step S4, cutting head and tail and milling surface: the homogenized 6061 aluminum alloy slab obtained in step S3 is subjected to cutting head and tail and milling surface, the head and tail of the slab are each cut off more than 300mm, and the upper and lower surfaces are each milled off more than 15mm, so as to obtain the 6061 aluminum alloy slab with machined and milled surface;

[0015] Step S5, preheating: the 6061 aluminum alloy slab with machined and milled surface is subjected to preheating, the preheating temperature is 420-460℃, and the holding time is 8-12h, so as to obtain the preheated 6061 aluminum alloy slab;

[0016] Step S6, hot rolling: The preheated 6061 aluminum alloy flat ingot is rolled in multiple passes to form an ultra-thick plate with a thickness of 260-410 mm. The final rolling temperature is controlled at 280-320℃ to obtain the hot-rolled 6061 aluminum alloy flat ingot.

[0017] Step S7, Solution quenching: The hot-rolled 6061 aluminum alloy flat ingot is subjected to offline solution quenching. The solution treatment process is as follows: the solution temperature is 520-545℃, and the heating and holding time is 300-450 min. The quenching process is as follows: the water temperature at the beginning of quenching is ≤30℃, and the circulating water is turned on during the immersion of the plate in the water tank to ensure that the water temperature at the end of quenching is ≤45℃.

[0018] Among them, the transfer time from the hot-rolled 6061 aluminum alloy flat ingot to the complete immersion in water after being lifted out of the heating furnace is ≤1min, and the immersion time of the plate in water is ≥30min, so as to obtain ultra-thick aluminum alloy quenched plate.

[0019] Step S8, Artificial Aging: The ultra-thick aluminum alloy quenched plate obtained in step S7 is subjected to artificial aging at an aging temperature of 160-180℃ and a holding time of 8-12h to obtain a T6 state 6061 aluminum alloy ultra-thick plate product.

[0020] Further, the composition and weight ratio of the high-purity ultra-thick 6061 aluminum alloy plate for semiconductor equipment in step S1 are as follows: Si 0.58-0.64%, Fe≤0.12%, Cu 0.22-0.25%, Mn≤0.05%, Mg 1.0-1.1%, Cr 0.18-0.25%, Zn≤0.05%, Ti≤0.05%, and the rest are Al and some unavoidable impurity elements.

[0021] Furthermore, in step S2, the online refining step controls the H content of the refined melt to be ≤0.1ml / 100g Al.

[0022] Furthermore, in step S2, the filtration step controls the mesh count of the filter plate to be ≥60 PPI.

[0023] Further, in step S3, the 6061 aluminum alloy flat ingot obtained in step S2 is subjected to homogenization heat treatment at a temperature of 570-590°C for a time of 22-30 hours to obtain a homogenized 6061 aluminum alloy flat ingot.

[0024] Further, in step S5, the 6061 aluminum alloy flat ingot with the machined and milled surface is preheated at a temperature of 430-460°C and held for 10-12 hours to obtain a preheated 6061 aluminum alloy flat ingot.

[0025] Further, the step S6 is carried out multi-pass rolling on the preheated 6061 aluminum alloy slab, and the 6061 aluminum alloy slab is rolled into an ultra-thick plate with a thickness of 260-410 mm, and the final rolling temperature is controlled to be 300-320 DEG C, so as to obtain the hot-rolled 6061 aluminum alloy slab.

[0026] Further, the step S6 is carried out multi-pass rolling on the preheated 6061 aluminum alloy slab, and the number of multi-pass rolling is 5-10 passes.

[0027] Further, the step S7 is carried out off-line solid solution quenching on the hot-rolled 6061 aluminum alloy slab, and the solid solution system is that the solid solution temperature is 530-545 DEG C, and the heating and holding time is 350-450 min; and the quenching system is that the water temperature at the beginning of quenching is less than or equal to 30 DEG C, and the plate is circulated in water during the immersion process to ensure that the water temperature at the end of quenching is less than or equal to 45 DEG C.

[0028] In the method, the transfer time of the hot-rolled 6061 aluminum alloy slab from the heating furnace to the immersion in water is less than or equal to 1 min, and the immersion time of the plate in water is greater than or equal to 30 min, so as to obtain the ultra-thick aluminum alloy quenched plate.

[0029] Further, the step S8 is carried out artificial aging on the ultra-thick aluminum alloy quenched plate prepared in the step S7, the aging temperature is 170-180 DEG C, and the holding time is 9-12 h, so as to obtain the T6 state 6061 aluminum alloy ultra-thick plate product.

[0030] The method for preparing the high-purity ultra-thick 6061 aluminum alloy plate for semiconductor equipment mainly aims at the complexity of forging technology and the limitation of forging ratio of the large-size, high-purity and ultra-thick aluminum alloy product with a thickness of greater than or equal to 260 mm, so that when the thickness meets the requirement of greater than or equal to 260 mm, the width and length cannot meet the requirements of greater than or equal to 1500 mm and greater than or equal to 3000 mm respectively, which leads to that the prepared ultra-thick 6061 aluminum alloy plate cannot be applied to some large-size semiconductor equipment, and the heat treatment process is optimized, so that the high-purity 6061 aluminum alloy has a relatively uniform and moderate microstructure and high mechanical properties under the condition that the number of grain growth inhibiting elements is small; under the design concept of low Fe, the number of Fe-rich phases in the alloy is reduced, and the high-temperature homogenization heat treatment is used to make the Fe-rich phases transform from coarse dendritic beta-AlFe phases to fine granular alpha-AlFe phases as much as possible, so that the size of the Fe-rich phases is reduced, and finally the high-purity 6061 aluminum alloy has excellent anodic oxidation performance and high mechanical properties, and meets the harsh requirements of semiconductor equipment on large-size ultra-thick aluminum alloy.

[0031] The application discloses a preparation method of high-purity super-thick 6061 aluminum alloy plate for semiconductor equipment.

[0032] The application discloses a preparation method of high-purity super-thick 6061 aluminum alloy plate for semiconductor equipment, and the heat treatment process is optimized, so that the high-purity 6061 aluminum alloy has a relatively uniform microstructure, a moderate size and high mechanical properties under the condition that the grain growth elements are less, the harsh requirements of semiconductor equipment on large-size super-thick aluminum alloy are met, and the application is applied to semiconductor equipment, thereby providing basic aluminum material guarantee for domestic semiconductor equipment. BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1 is an oxidation effect drawing of the high-purity super-thick 6061 aluminum alloy plate for semiconductor equipment prepared in the embodiment 1 and having a thickness of 260 mm in the thickness direction, and it can be seen that the high-purity super-thick 6061 aluminum alloy plate prepared in the embodiment 1 has excellent anodic oxidation performance;

[0034] Figure 2 is an oxidation effect drawing of the high-purity super-thick 6061 aluminum alloy plate for semiconductor equipment prepared in the embodiment 2 and having a thickness of 368 mm in the thickness direction, and it can be seen that the high-purity super-thick 6061 aluminum alloy plate prepared in the embodiment 2 has excellent anodic oxidation performance;

[0035] Figure 3 is an oxidation effect drawing of the high-purity super-thick 6061 aluminum alloy plate for semiconductor equipment prepared in the embodiment 3 and having a thickness of 405 mm in the thickness direction, and it can be seen that the high-purity super-thick 6061 aluminum alloy plate prepared in the embodiment 3 has excellent anodic oxidation performance;

[0036] Figure 4 is a microstructure drawing of the high-purity super-thick 6061 aluminum alloy plate for semiconductor equipment prepared in the embodiment 1 and having a thickness of 260 mm;

[0037] Figure 5is a microstructure picture of the core of the high-purity super-thick 6061 aluminum alloy plate for semiconductor equipment with a thickness of 368 mm prepared by the embodiment 2 of the present application;

[0038] Figure 6 is a microstructure picture of the core of the high-purity super-thick 6061 aluminum alloy plate for semiconductor equipment with a thickness of 405 mm prepared by the embodiment 3 of the present application;

[0039] Figure 7 is a Fe-rich phase appearance picture of the high-purity super-thick 6061 aluminum alloy plate for semiconductor equipment with a thickness of 260 mm prepared by the embodiment 1 of the present application;

[0040] Figure 8 is a Fe-rich phase appearance picture of the high-purity super-thick 6061 aluminum alloy plate for semiconductor equipment with a thickness of 368 mm prepared by the embodiment 2 of the present application;

[0041] Figure 9 is a Fe-rich phase appearance picture of the high-purity super-thick 6061 aluminum alloy plate for semiconductor equipment with a thickness of 405 mm prepared by the embodiment 3 of the present application;

[0042] Figure 10 is a picture of the high-purity super-thick 6061 aluminum alloy plate for semiconductor equipment with a thickness of 260 mm prepared by the embodiment 1 of the present application applied to a cavity of a certain type of semiconductor equipment;

[0043] Figure 11 is a picture of the high-purity super-thick 6061 aluminum alloy plate for semiconductor equipment with a thickness of 368 mm prepared by the embodiment 2 of the present application applied to a cavity of a certain type of semiconductor equipment;

[0044] Figure 12 is a picture of the high-purity super-thick 6061 aluminum alloy plate for semiconductor equipment with a thickness of 405 mm prepared by the embodiment 3 of the present application applied to a cavity of a certain type of semiconductor equipment. DETAILED DESCRIPTION

[0045] The following examples can help those skilled in the art to have a more comprehensive understanding of the present application, but can not limit the present application in any way.

[0046] Embodiment 1: producing high-purity super-thick 6061 aluminum alloy plate for semiconductor equipment with a thickness of 260 mm

[0047] A 6061 aluminum alloy for semiconductor equipment, the alloy composition consists of the following components by mass percentage: Si 0.61%, Fe 0.10%, Cu 0.22%, Mn 0.03%, Mg 1.0%, Cr 0.21%, Zn 0.03%, Ti 0.03%, the balance being Al and inevitable elements; and a preparation method of the large-size super-thick 6061 aluminum alloy plate for semiconductor equipment, the operation steps are as follows:

[0048] (1) Ingot casting: according to the designed alloy composition, after the processes of melting, composition adjustment, converter, online refining (the H content of the melt after refining is 0.0988 ml / 100g Al), filtration (60PPI filter plate is used), and standing, the size of the ingot is 550mm×1750mm×6000mm;

[0049] (2) Homogenization heat treatment: the ingot prepared in (1) is placed in a heating furnace for homogenization heat treatment, the homogenization temperature is 564℃, and the homogenization time is 30h, thereby obtaining an ingot with eliminated casting defects;

[0050] (3) Head and tail cutting and face milling: the ingot prepared in (2) is cut at the head, tail and surface, wherein the head and tail are each cut by 300mm, and the upper and lower surfaces are each milled by 15mm;

[0051] (4) Preheating: the ingot prepared in step (3) is placed in a heating furnace for preheating, the heating temperature is 460℃, and the holding time is 8h;

[0052] (5) Hot rolling: after preheating in (4), the ingot is subjected to multi-pass hot rolling to obtain an aluminum alloy plate with a thickness of 260mm, and the final rolling temperature is controlled to be 280℃ by increasing the amount of emulsion spraying during rolling;

[0053] (6) Solution quenching: the 260mm plate prepared in (5) is subjected to solution quenching, the solution temperature is 522℃, the heating and holding time is 302min, the transfer time is 50s, the water temperature at the beginning of quenching is 28℃, the water temperature at the end of quenching is 42℃, and the soaking time is 35min, thereby obtaining an aluminum alloy quenched super-thick plate;

[0054] (7) Artificial aging: the plate prepared in (6) is subjected to artificial aging, the aging temperature is 171℃, and the holding time is 10h, thereby obtaining a 260mm 6061 aluminum alloy plate product;

[0055] (8) Detection: the plate prepared in (7) is detected, and the detection items include the anodic oxidation performance in the thickness direction of the plate, the mechanical properties, the microstructure and the Fe-rich phase morphology of the core of the plate.

[0056] Example 2: Producing high-purity super-thick 6061 aluminum alloy plate with thickness of 368 mm for semiconductor equipment

[0057] A 6061 aluminum alloy for semiconductor equipment, the alloy composition consists of the following components by mass percentage: Si 0.60%, Fe 0.09%, Cu 0.24%, Mn 0.03%, Mg 0.93%, Cr 0.17%, Zn 0.02%, Ti 0.02%, the balance being Al and inevitable elements; the preparation method of the large-size super-thick 6061 aluminum alloy plate for semiconductor equipment, the operation steps are as follows:

[0058] (1) Ingot casting: according to the designed alloy composition, after melting, composition adjustment, converter, online refining (H content of the melt after refining is 0.0954 ml / 100g Al), filtration (using 60PPI filter plate), and standing, the size of the ingot is 550mm×1750mm×6000mm;

[0059] (2) Homogenization heat treatment: the ingot prepared in (1) is placed in a heating furnace for homogenization heat treatment, the homogenization temperature is 588℃, the homogenization time is 20h, and the ingot with eliminated casting defects is obtained;

[0060] (3) Cutting head and tail and milling surface: the head, tail and surface of the ingot prepared in (2) are cut off, wherein the head and tail are each 300mm, and the upper and lower surfaces are each milled off 15mm;

[0061] (4) Preheating: the ingot prepared in step (3) is placed in a heating furnace for preheating, the heating temperature is 440℃, and the holding time is 10 hours;

[0062] (5) Hot rolling: according to (4) after preheating, the ingot is subjected to multi-pass hot rolling to obtain an aluminum alloy plate with a thickness of 368mm, and the finish rolling temperature is controlled to be 295℃ by emulsion spraying during rolling;

[0063] (6) Solution quenching: the 368mm plate prepared in (5) is subjected to solution quenching, the solution temperature is 535℃, the heating and holding time is 392min, the transfer time is 55s, the water temperature at the beginning of quenching is 28℃, the water temperature at the end of quenching is 43℃, and the soaking time is 38min, and the quenched aluminum alloy super-thick plate is obtained;

[0064] (7) Artificial aging: the plate prepared in (6) is subjected to artificial aging, the aging temperature is 180℃, and the holding time is 8h, and the 368mm 6061 aluminum alloy plate is obtained;

[0065] (8) Detection: the plate prepared in (7) is detected, and the detection items include the anodic oxidation performance in the thickness direction of the plate, the mechanical properties, the microstructure and the Fe-rich phase morphology of the core of the plate.

[0066] Example 3: Production of high-purity ultra-thick 6061 aluminum alloy plate with a thickness of 405 mm for semiconductor equipment

[0067] A 6061 aluminum alloy for semiconductor equipment, the alloy composition consists of the following components by mass percentage: Si 0.60%, Fe 0.10%, Cu 0.23%, Mn 0.02%, Mg 1.08%, Cr 0.24%, Zn 0.02%, Ti 0.02%, the balance being Al and unavoidable elements; the preparation method of the large-size ultra-thick 6061 aluminum alloy plate for semiconductor equipment, the operation steps are as follows:

[0068] (1) Ingot casting: according to the designed alloy composition, after melting, composition adjustment, converter, online refining (H content of the melt after refining is 0.0975 ml / 100g Al), filtration (using 60PPI filter plate), and standing, the size of the ingot is 550mm×1750mm×6000mm;

[0069] (2) Homogenization heat treatment: the ingot prepared in (1) is placed in a heating furnace for homogenization heat treatment, the homogenization temperature is 576℃, and the homogenization time is 26h, to obtain an ingot with eliminated casting defects;

[0070] (3) Cutting head and tail and milling surface: the head, tail and surface of the ingot prepared in (2) are cut off, wherein the head and tail are each 300mm, and the upper and lower surfaces are each milled off 15mm;

[0071] (4) Preheating: the ingot prepared in step (3) is placed in a heating furnace for preheating, the heating temperature is 420℃, and the holding time is 12 hours;

[0072] (5) Hot rolling: according to (4) after preheating, the ingot is subjected to multi-pass hot rolling to obtain an aluminum alloy plate with a thickness of 405mm, and the final rolling temperature is controlled to be 320℃ by emulsion spraying during rolling;

[0073] (6) Solution quenching: the 405mm plate prepared in (5) is subjected to solution quenching, the solution temperature is 545℃, the heating and holding time is 448min, the transfer time is 54s, the water temperature at the beginning of quenching is 28℃, the water temperature at the end of quenching is 45℃, and the soaking time is 43min, and the quenching obtains an aluminum alloy quenched ultra-thick plate;

[0074] (7) Artificial aging: the plate prepared in (6) is subjected to artificial aging, the aging temperature is 162℃, and the aging time is 12h, to obtain a 405mm 6061 aluminum alloy plate product;

[0075] (8) Detection: the plate prepared in (7) is subjected to detection, and the detection items include the anodic oxidation performance in the thickness direction of the plate, the mechanical properties, the microstructure and the Fe-rich phase morphology in the core of the plate.

[0076] Example 4: Production of a high-purity ultra-thick 6061 aluminum alloy plate with a thickness of 405mm for semiconductor equipment

[0077] A 6061 aluminum alloy for semiconductor equipment, the alloy composition consists of the following components by mass percentage: Si 0.60%, Fe 0.10%, Cu 0.23%, Mn 0.02%, Mg 1.08%, Cr 0.24%, Zn 0.02%, Ti 0.02%, and the balance of Al and inevitable elements; and a preparation method of the large-size ultra-thick 6061 aluminum alloy plate for semiconductor equipment, the operation steps are as follows:

[0078] (1) Ingot casting: according to the designed alloy composition, after the processes of melting, composition adjustment, converter, online refining (the H content of the melt after refining is 0.1547ml / 100g Al), filtration (using a 60PPI filter plate), and standing, the size of the ingot is 550mm×1750mm×6000mm;

[0079] (2) Homogenization heat treatment: the ingot prepared in (1) is placed in a heating furnace for homogenization heat treatment, the homogenization temperature is 576℃, and the homogenization time is 26h, to obtain an ingot with eliminated casting defects;

[0080] (3) Cutting head and tail and milling surface: the head, tail and surface of the ingot prepared in (2) are cut off, wherein the head and tail are each cut off by 300mm, and the upper and lower surfaces are each milled off by 15mm;

[0081] (4) Preheating: the ingot prepared in step (3) is placed in a heating furnace for preheating, the heating temperature is 420℃, and the holding time is 12h;

[0082] (5) Hot rolling: the ingot is subjected to multi-pass hot rolling after preheating in (4), to obtain an aluminum alloy plate with a thickness of 405mm, and the final rolling temperature is controlled to be 320℃ by spraying emulsion during rolling;

[0083] (6) solution quenching: the 405 mm plate prepared in (5) is subjected to solution quenching, the solution temperature is 545℃, the heating and holding time is 448 min, the transfer time is 54 s, the water temperature at the beginning of quenching is 28℃, the water temperature at the end of quenching is 45℃, and the soaking time is 43 min, and the quenching obtains an aluminum alloy quenched super-thick plate;

[0084] (7) artificial aging: the plate prepared in (6) is subjected to artificial aging, the aging temperature is 162℃, and the holding time is 12 h, thereby obtaining a 405 mm 6061 aluminum alloy plate product;

[0085] (8) detection: the plate prepared in (7) is subjected to detection, and the detection items include the anodic oxidation performance in the thickness direction of the plate, the mechanical properties, the microstructure and the Fe-rich phase morphology in the core of the plate.

[0086] Comparative Example 1: production of a high-purity super-thick 6061 aluminum alloy plate for semiconductor equipment with a thickness of 405 mm

[0087] A 6061 aluminum alloy for semiconductor equipment, the alloy composition comprises, by mass percent: Si 0.58%, Fe 0.3%, Cu 0.23%, Mn 0.1%, Mg 1.08%, Cr 0.24%, Ti 0.02%, and the balance being Al and unavoidable elements; and a preparation method of the large-size super-thick 6061 aluminum alloy plate for semiconductor equipment, the operation steps being as follows:

[0088] (1) flat ingot casting: ingredients are prepared according to the designed alloy composition, after processes such as melting, composition adjustment, converter, online refining (H content of the melt after refining is 0.0975 ml / 100g Al), filtration (60PPI filter plate is used), and standing, the specification of the flat ingot is 550mm×1750mm×6000mm;

[0089] (2) homogenization heat treatment: the flat ingot prepared in (1) is placed into a heating furnace for homogenization heat treatment, the homogenization temperature is 576℃, and the homogenization time is 26 h, thereby obtaining a flat ingot with eliminated casting defects;

[0090] (3) cutting head and tail and milling surface: the head, tail and surface of the flat ingot prepared in (2) are cut off, wherein the head and tail are each cut off by 300 mm, and the upper and lower surfaces are each milled off by 15 mm;

[0091] (4) preheating: the flat ingot prepared in step (3) is placed into a heating furnace for preheating, the heating temperature is 420℃, and the holding time is 12 h;

[0092] (5) hot rolling: the flat ingot after preheating in (4) is subjected to multi-pass hot rolling to obtain an aluminum alloy plate with a thickness of 405 mm, and the final rolling temperature is controlled to be 320℃ by emulsion spraying during the rolling process;

[0093] (6) solution quenching: the 405 mm plate prepared in (5) is subjected to solution quenching, the solution temperature is 545℃, the heating and holding time is 448 min, the transfer time is 54 s, the water temperature at the beginning of quenching is 28℃, the water temperature at the end of quenching is 45℃, and the soaking time is 43 min, and the quenching obtains an aluminum alloy quenched super-thick plate;

[0094] (7) artificial aging: the plate prepared in (6) is subjected to artificial aging, the aging temperature is 162℃, and the holding time is 12 h, thereby obtaining a 405 mm 6061 aluminum alloy plate product;

[0095] (8) detection: the plate prepared in (7) is subjected to detection, and the detection items include the anodic oxidation performance in the thickness direction of the plate, the mechanical properties, the microstructure and the Fe-rich phase morphology in the core of the plate.

[0096] Comparative Example 2: production of a high-purity super-thick 6061 aluminum alloy plate for semiconductor equipment with a thickness of 405 mm

[0097] A 6061 aluminum alloy for semiconductor equipment, the alloy composition comprises the following components by mass percentage: Si 0.60%, Fe 0.10%, Cu 0.23%, Mn 0.02%, Mg 1.08%, Cr 0.24%, Zn 0.02%, Ti 0.02%, and the balance is Al and inevitable elements; and a preparation method of the large-size super-thick 6061 aluminum alloy plate for semiconductor equipment, the operation steps are as follows:

[0098] (1) flat ingot casting: ingredients are prepared according to the designed alloy composition, after the processes of melting, composition adjustment, converter, online refining (the H content of the melt after refining is 0.0975 ml / 100g Al), filtration (60PPI filter plate is used), and standing, the specification of the flat ingot is 550mm×1750mm×6000mm;

[0099] (2) homogenization heat treatment: the flat ingot prepared in (1) is placed into a heating furnace for homogenization heat treatment, the homogenization temperature is 576℃, and the homogenization time is 26 h, thereby obtaining a flat ingot with eliminated casting defects;

[0100] (3) cutting head and tail and milling surface: the head, tail and surface of the flat ingot prepared in (2) are cut off, wherein the head and tail are each cut off by 300 mm, and the upper and lower surfaces are each milled off by 15 mm;

[0101] (4) preheating: the flat ingot prepared in step (3) is placed into a heating furnace for preheating, the heating temperature is 420℃, and the holding time is 12 h;

[0102] (5) Hot rolling: after preheating according to (4), the slab is subjected to multi-pass hot rolling to obtain an aluminum alloy plate with a thickness of 405 mm, and the final rolling temperature is controlled to be 320℃ by spraying emulsion during rolling;

[0103] (6) Solution quenching: the 405 mm plate prepared in (5) is subjected to solution quenching, the solution temperature is 480℃, the heating and holding time is 550 min, the transfer time is 54 s, the water temperature at the beginning of quenching is 28℃, the water temperature at the end of quenching is 85℃, and the soaking time is 43 min, and the quenching obtains an aluminum alloy quenched ultra-thick plate;

[0104] (7) Artificial aging: the plate prepared in (6) is subjected to artificial aging, the aging temperature is 162℃, and the holding time is 12 h, to obtain a 405 mm 6061 aluminum alloy plate product;

[0105] (8) Detection: the plate prepared in (7) is subjected to detection, and the detection items include the anodic oxidation performance in the thickness direction of the plate, the mechanical properties, the microstructure and the Fe-rich phase morphology of the core of the plate.

[0106] Comparative Example 3: Production of a high-purity ultra-thick 6061 aluminum alloy plate with a thickness of 260 mm for semiconductor equipment

[0107] A 6061 aluminum alloy for semiconductor equipment, the alloy composition consists of the following components by mass percentage: Si 0.58%, Fe 0.3%, Cu 0.23%, Mn 0.1%, Mg 1.08%, Cr 0.24%, Ti 0.02%, and the balance being Al and unavoidable elements; and a preparation method of the large-size ultra-thick 6061 aluminum alloy plate for semiconductor equipment, the operation steps are as follows:

[0108] (1) Slab casting: according to the designed alloy composition, after melting, composition adjustment, converter, online refining (the H content of the melt after refining is 0.0988 ml / 100g Al), filtration (using a 60PPI filter plate), and standing, the slab has a size of 550 mm x 1750 mm x 6000 mm;

[0109] (2) Homogenization heat treatment: the slab prepared in (1) is placed in a heating furnace for homogenization heat treatment, the homogenization temperature is 564℃, and the homogenization time is 30 h, to obtain a slab with eliminated casting defects;

[0110] (3) Cutting head and tail and milling surface: the head, tail and surface of the slab prepared in (2) are cut off, wherein the head and tail are each cut off by 300 mm, and the upper and lower surfaces are each milled off by 15 mm;

[0111] (4) Preheating: the slab prepared in step (3) is placed in a heating furnace for preheating, the heating temperature is 460℃, and the holding time is 8 hours;

[0112] (5) Hot rolling: after preheating according to (4), the slab is subjected to multi-pass hot rolling to obtain an aluminum alloy plate with a thickness of 260 mm, and the final rolling temperature is controlled to be 280°C by increasing the amount of emulsion spraying during rolling;

[0113] (6) Solution quenching: the 260 mm plate prepared in (5) is subjected to solution quenching, the solution temperature is 522°C, the heating and holding time is 302 min, the transfer time is 50 s, the water temperature at the beginning of quenching is 28°C, the water temperature at the end of quenching is 42°C, and the soaking time is 35 min, and the quenched aluminum alloy super-thick plate is obtained;

[0114] (7) Artificial aging: the plate prepared in (6) is subjected to artificial aging, the aging temperature is 171°C, and the holding time is 10 h, and a 260 mm 6061 aluminum alloy plate product is obtained;

[0115] (8) Detection: the plate prepared in (7) is detected, and the detection items include the anodic oxidation performance in the thickness direction of the plate, the mechanical properties, the microstructure and the Fe-rich phase morphology of the core of the plate.

[0116] Comparative Example 4: Production of a high-purity super-thick 6061 aluminum alloy plate with a thickness of 260 mm for semiconductor equipment

[0117] A 6061 aluminum alloy for semiconductor equipment, the alloy composition consists of the following components by mass percentage: Si 0.61%, Fe 0.10%, Cu 0.22%, Mn 0.03%, Mg 1.0%, Cr 0.21%, Zn 0.03%, Ti 0.03%, and the balance is Al and unavoidable elements; and a preparation method of the large-size super-thick 6061 aluminum alloy plate for semiconductor equipment, the operation steps are as follows:

[0118] (1) Slab casting: according to the designed alloy composition, after melting, composition adjustment, converter, online refining (the H content of the melt after refining is 0.0988 ml / 100g Al), filtration (using a 60PPI filter plate), and standing, the slab has a size of 550 mm x 1750 mm x 6000 mm;

[0119] (2) Homogenization heat treatment: the slab prepared in (1) is placed in a heating furnace for homogenization heat treatment, the homogenization temperature is 564°C, and the homogenization time is 30 h, and a slab with eliminated casting defects is obtained;

[0120] (3) Cutting head and tail and milling surface: the head, tail and surface of the slab prepared in (2) are cut off, wherein the head and tail are each 300 mm, and the upper and lower surfaces are each milled off 15 mm;

[0121] (4) preheating: the slab prepared in step (3) is put into a heating furnace for preheating, the heating temperature is 460℃, and the holding time is 8 hours;

[0122] (5) hot rolling: the slab is subjected to multi-pass hot rolling after preheating according to (4), and an aluminum alloy plate with a thickness of 260mm is obtained, and the final rolling temperature is controlled to be 280℃ by increasing the amount of emulsion spraying during rolling;

[0123] (6) solution quenching: the 260mm plate prepared in (5) is subjected to solution quenching, the solution temperature is 560℃, the heating and holding time is 448min, the transfer time is 50s, the water temperature at the beginning of quenching is 28℃, the water temperature at the end of quenching is 55℃, and the soaking time is 35min, and the quenching obtains an aluminum alloy quenched super-thick plate;

[0124] (7) artificial aging: the plate prepared in (6) is subjected to artificial aging, the aging temperature is 171℃, and the holding time is 10h, and a 260mm 6061 aluminum alloy plate product is obtained;

[0125] (8) detection: the plate prepared in (7) is detected, and the detection items include the anodic oxidation performance in the thickness direction of the plate, the mechanical properties, the microstructure and the Fe-rich phase morphology in the core of the plate.

[0126] The properties of the plates prepared in the above examples 1-4 and comparative examples 1-4 are detected, and the detection results are shown in Table 1.

[0127] Table 1 Performance parameter table of high-purity super-thick 6061 aluminum alloy plate for semiconductor equipment

[0128]

[0129] Comparative example 1 and comparative example 3 mainly change the mass percentage composition of the alloy, and according to the test results of comparative example 1, comparative example 3 and example 1-4 of the present application, according to the design concept of high-purity aluminum alloy, the content range of low Fe, Mn, Zn and Ti elements is accurately designed, and according to the principle of interaction of Cu, Si, Mg and Cr elements and the influence on the anodic oxidation performance, the content range of Cu, Si, Mg and Cr elements with excellent anodic oxidation performance is accurately designed, combined with the high cleanliness requirement of melt H content less than 0.1ml / 100g Al and filter plate greater than 60PPi, the alloy has high purity characteristics, and the high-purity 6061 aluminum alloy has excellent anodic oxidation performance and high mechanical properties, and meets the harsh requirements of semiconductor equipment on large-size super-thick aluminum alloy.

[0130] Comparative example 2 and comparative example 4 mainly change the off-line solution quenching process, and according to the test results of comparative example 2, comparative example 4 and example 1-4 of the present application,

[0131] The application optimizes the heat treatment process, can make the high-purity 6061 aluminum alloy have relatively uniform, moderate size microstructure and high mechanical properties in the case of less grain growth inhibition elements, meets the harsh requirements of semiconductor equipment on large-size ultra-thick aluminum alloy, and has been applied in semiconductor equipment, providing basic aluminum material guarantee for domestic semiconductor equipment.

[0132] The foregoing description of specific exemplary embodiments of the application is intended to be illustrative only and is not intended to limit the application to the precise forms described. Many modifications and variations are possible in light of the above teachings without departing from the spirit or essential characteristics of the application. The exemplary embodiments were chosen and described in order to explain the principles of the application and its practical application and to allow others skilled in the art to understand the application for various exemplary embodiments with various modifications being applicable. The scope of the application is intended to be defined by the claims and their equivalents.

Claims

1. A method for producing a high purity ultra-thick 6061 aluminum alloy plate for semiconductor equipment, characterized by, The method comprises the following steps: Step S1, batching: the composition and weight ratio of the high-purity ultra-thick 6061 aluminum alloy plate for semiconductor equipment are as follows: Si 0.56-0.64%, Fe ≤ 0.12%, Cu 0.20-0.25%, Mn ≤ 0.05%, Mg 0.9-1.1%, Cr 0.15-0.25%, Zn ≤ 0.05%, Ti ≤ 0.05%, and the rest is Al and some inevitable impurity elements; Step S2, casting: the high-purity ultra-thick 6061 aluminum alloy plate for semiconductor equipment in step S1 is batched according to the composition and ratio, and then subjected to melting, composition adjustment, converter, online refining, filtering, standing and casting to obtain a 6061 aluminum alloy slab; Step S3, homogenization heat treatment: the 6061 aluminum alloy slab obtained in step S2 is subjected to homogenization heat treatment, the homogenization temperature is 560-590 ℃, and the homogenization time is 18-30 h, to obtain a homogenized 6061 aluminum alloy slab; Step S4, cutting head and tail and milling surface: the homogenized 6061 aluminum alloy slab obtained in step S3 is subjected to cutting head and tail and milling surface, the head and tail of the slab are each cut off more than 300 mm, and the upper and lower surfaces are each milled off more than 15 mm, to obtain a 6061 aluminum alloy slab with machined and milled surface; Step S5, preheating: the 6061 aluminum alloy slab with machined and milled surface is preheated, the preheating temperature is 420-460 ℃, and the holding time is 8-12 h, to obtain a preheated 6061 aluminum alloy slab; Step S6, hot rolling: the preheated 6061 aluminum alloy slab is subjected to multi-pass rolling to form an ultra-thick plate with a thickness of 260-410 mm, and the final rolling temperature is controlled to be 280-320 ℃, to obtain a hot-rolled 6061 aluminum alloy slab; Step S7, solution quenching: the hot-rolled 6061 aluminum alloy slab is subjected to offline solution quenching, the solution quenching system is as follows: the solution temperature is 520-545 ℃, and the heating and holding time is 300-450 min; the quenching system is as follows: the water temperature at the beginning of quenching is ≤ 30 ℃, and the plate is circulated in water during the immersion process to ensure that the water temperature at the end of quenching is ≤ 45 ℃; wherein, the transfer time of the hot-rolled 6061 aluminum alloy slab from the heating furnace to complete immersion in water is ≤ 1 min, and the immersion time of the plate in water is ≥ 30 min, to obtain an ultra-thick aluminum alloy quenched plate; Step S8, artificial aging: the ultra-thick aluminum alloy quenched plate obtained in step S7 is subjected to artificial aging, the aging temperature is 160-180 ℃, and the holding time is 8-12 h, to obtain a T6 state 6061 aluminum alloy ultra-thick plate product; In the online refining step in step S2, the H content of the refined melt is controlled to be ≤ 0.1 ml / 100 g Al; In the filtering step in step S2, the mesh number of the filter plate is controlled to be ≥ 60 PPI.

2. The method of producing a high purity ultra-thick 6061 aluminum alloy plate for a semiconductor device according to claim 1, characterized in that, The composition and weight ratio of the high-purity super-thick 6061 aluminum alloy plate for semiconductor equipment in the step S1 are as follows: Si 0.58-0.64%, Fe ≤ 0.12%, Cu 0.22-0.25%, Mn ≤ 0.05%, Mg 1.0-1.1%, Cr 0.18-0.25%, Zn ≤ 0.05%, Ti ≤ 0.05%, and the rest is Al and some inevitable impurity elements.

3. The method for preparing a high-purity, ultra-thick 6061 aluminum alloy plate for semiconductor devices according to claim 1, characterized in that, In the step S3, the 6061 aluminum alloy slab prepared in the step S2 is subjected to homogenization heat treatment, the homogenization temperature is 570-590 ℃, and the homogenization time is 22-30 h, so as to obtain the 6061 aluminum alloy slab after homogenization.

4. The method for preparing a high-purity, ultra-thick 6061 aluminum alloy plate for semiconductor devices according to claim 1, characterized in that, In the step S5, the 6061 aluminum alloy slab after milling is subjected to preheating, the preheating temperature is 430-460 ℃, the holding time is 10-12 h, so as to obtain the 6061 aluminum alloy slab after preheating.

5. The method for preparing a high-purity, ultra-thick 6061 aluminum alloy plate for semiconductor devices according to claim 1, characterized in that, In the step S6, the 6061 aluminum alloy slab after preheating is subjected to multi-pass rolling, so as to obtain the super-thick plate with a thickness of 260-410 mm, and the final rolling temperature is controlled to be 300-320 ℃, so as to obtain the 6061 aluminum alloy slab after hot rolling.

6. The method of producing a high purity ultra-thick 6061 aluminum alloy plate for a semiconductor device according to claim 1, characterized in that, In the step S6, the 6061 aluminum alloy slab after preheating is subjected to multi-pass rolling, and the number of multi-pass rolling is 5-10 passes.

7. The method of producing a high purity ultra-thick 6061 aluminum alloy plate for a semiconductor device according to claim 1, wherein In the step S7, the 6061 aluminum alloy slab after hot rolling is subjected to off-line solid solution quenching, the solid solution system is as follows: the solid solution temperature is 530-545 ℃, and the heating and holding time is 350-450 min; the quenching system is as follows: the water temperature at the beginning of quenching is ≤ 30 ℃, and the plate is circulated in the water pool during the soaking process to ensure that the water temperature at the end of quenching is ≤ 45 ℃; wherein, the transfer time of the 6061 aluminum alloy slab after hot rolling from the heating furnace to the completion of immersion in water is ≤ 1 min, and the soaking time of the plate in water is ≥ 30 min, so as to obtain the super-thick aluminum alloy quenched plate.

8. The method of producing a high purity ultra-thick 6061 aluminum alloy plate for a semiconductor device according to claim 1, characterized in that, In the step S8, the super-thick aluminum alloy quenched plate prepared in the step S7 is subjected to artificial aging, the aging temperature is 170-180 ℃, and the holding time is 9-12 h, so as to obtain the T6 state 6061 aluminum alloy super-thick plate product.

Images