WO2022095336A1 - 一种铬硅合金溅射靶材的制备方法 - Google Patents

一种铬硅合金溅射靶材的制备方法 Download PDF

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WO2022095336A1
WO2022095336A1 PCT/CN2021/086058 CN2021086058W WO2022095336A1 WO 2022095336 A1 WO2022095336 A1 WO 2022095336A1 CN 2021086058 W CN2021086058 W CN 2021086058W WO 2022095336 A1 WO2022095336 A1 WO 2022095336A1
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temperature program
chromium
silicon
optionally
powder
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PCT/CN2021/086058
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English (en)
French (fr)
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姚力军
边逸军
潘杰
王学泽
杨慧珍
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宁波江丰电子材料股份有限公司
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Publication of WO2022095336A1 publication Critical patent/WO2022095336A1/zh

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    • CCHEMISTRY; METALLURGY
    • C23COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23CCOATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C14/00Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
    • C23C14/22Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material characterised by the process of coating
    • C23C14/34Sputtering
    • C23C14/3407Cathode assembly for sputtering apparatus, e.g. Target
    • C23C14/3414Metallurgical or chemical aspects of target preparation, e.g. casting, powder metallurgy
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C1/00Making non-ferrous alloys
    • C22C1/04Making non-ferrous alloys by powder metallurgy
    • C22C1/05Mixtures of metal powder with non-metallic powder
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C27/00Alloys based on rhenium or a refractory metal not mentioned in groups C22C14/00 or C22C16/00
    • C22C27/06Alloys based on chromium

Definitions

  • the present application belongs to the technical field of semiconductors, and relates to a method for preparing a sputtering target, for example, to a method for preparing a chromium-silicon alloy sputtering target.
  • Magnetron sputtering is a coating process that bombards the target with charged particles, so that the atoms of the target overflow from the surface and are uniformly deposited on the substrate. Due to the advantages of good adhesion between layers and excellent film uniformity, magnetron sputtering technology has been widely used in the manufacture of integrated circuits, information storage devices, liquid crystal displays, laser memory and electronic control devices and other electronic and information industries. in the process.
  • the quality of the target used in the magnetron sputtering process is one of the key factors affecting the quality of the magnetron sputtering coating, so the quality requirements for the sputtering target are higher than those of the traditional material industry, and the general quality of the sputtering target is
  • the requirements mainly include requirements for size, flatness, purity, component content, density, grain size and defect control; in addition, surface roughness, resistance value, grain size uniformity, composition and structure uniformity, oxidation In terms of material content and size, magnetic permeability, ultra-high density and ultra-fine grains, etc., sputtering targets have higher quality requirements or special quality requirements.
  • Silicon-chromium alloy sputtering target is a new type of sputtering target. As a good conductor for vacuum sputtering, it can be used in the fields of electronic gate materials and electronic thin films. In order to make the silicon-chromium alloy sputtering target exert good performance during vacuum sputtering, the silicon-chromium alloy sputtering target is required to have high density, high uniformity of internal structure and better machining conditions .
  • CN 105331939A discloses a silicon-containing alloy target and a preparation method thereof.
  • the preparation method includes the following steps: (1) preparation of pre-alloyed powder; (2) cold isostatic pressing of the pre-alloyed powder to obtain cold isostatic pressing, and packing it into the envelope; (3) degassing the envelope packed into the cold isostatic pressing to obtain a degassed ingot; (4) degassing the degassed billet; The gasified ingot is subjected to hot isostatic pressing to obtain a pressed ingot, and then the envelope is removed to obtain a pressed ingot; (5) the pressed ingot is machined to obtain a silicon-containing alloy target.
  • the pressure required for cold isostatic pressing is relatively high, and there are relatively high requirements for the preparation equipment.
  • CN 104419859A discloses a chromium-aluminum-silicon alloy target, wherein the atomic percentage of chromium is 5-75%, the atomic percentage of aluminum is 10-90%, and the atomic percentage of silicon is 1-20%.
  • the preparation method of the target material includes the following steps: (1) preparation of alloy powder; (2) cold isostatic pressing of the prepared alloy powder; (3) cold isostatic pressing of the blank degassing; (4) hot isostatic pressing of the degassed billet; (5) machining of the hot isostatic pressed billet, and cleaning to obtain the desired finished alloy target material.
  • Cold isostatic pressing is still required during the processing of the chromium-aluminum-silicon alloy target, which requires high equipment and is not conducive to reducing the manufacturing cost of the chromium-aluminum-silicon alloy target.
  • CN 111058004A discloses a preparation method of a chromium-silicon alloy sputtering target, the preparation method comprising the following steps: (1) loading the chromium-silicon alloy powder with the target mass ratio into a mold and sealing, and carrying out a vibrating treatment; ( 2) degassing the vibrated mold in step (1); (3) subjecting the degassed mold in step (2) to hot isostatic pressing at 1000-1350° C. to obtain a chrome-silicon alloy sputtering target (4) Machining the crude chromium-silicon alloy sputtering target obtained in step (3) to obtain a chromium-silicon alloy sputtering target.
  • the preparation method can obtain the chromium-silicon alloy sputtering target through simple hot isostatic pressing, but its density needs to be further improved.
  • the purpose of this application is to provide a method for preparing a chrome-silicon alloy sputtering target, which enables the prepared chrome-silicon alloy sputtering target to have high density, uniform and dense microscopically, and no voids and delaminations.
  • the structure can improve the good performance guarantee for the subsequent sputtering use.
  • the application provides a preparation method of a chromium-silicon alloy sputtering target, the preparation method comprising the following steps:
  • the non-oxidizing atmosphere in step (1) includes nitrogen atmosphere and/or inert atmosphere.
  • the inert atmosphere includes any one or a combination of at least two of a helium gas atmosphere, a neon gas atmosphere, an argon gas atmosphere or a krypton gas atmosphere.
  • the gas used in the inert atmosphere described in this application includes any one or a combination of at least two of helium, neon, argon or krypton.
  • Typical but non-limiting combinations include a combination of helium and neon, and neon Combination with Argon, Combination of Argon and Krypton, Combination of Neon and Krypton, Combination of Helium and Argon, Combination of Argon, Neon and Helium, or Helium, Neon, Argon Combination with krypton.
  • the purity of the chromium powder is ⁇ 99.95%, such as 99.95%, 99.96%, 99.97%, 99.98%, 99.99%, 99.992%, 99.994%, 99.995%, 99.996%, 99.998% or 99.999%, However, it is not limited to the recited values, and other non-recited values within the numerical range are equally applicable.
  • the particle size of the chromium powder is less than 45 ⁇ m, for example, it can be 5 ⁇ m, 10 ⁇ m, 15 ⁇ m, 20 ⁇ m, 25 ⁇ m, 30 ⁇ m, 35 ⁇ m, 40 ⁇ m or 44 ⁇ m, but not limited to the listed numerical values, and other unlisted values within the numerical range The same applies to numerical values.
  • the purity of the silicon powder is greater than or equal to 99.99%, for example, it can be 99.99%, 99.992%, 99.994%, 99.995%, 99.996%, 99.998% or 99.999%, but not limited to the listed values, other values within the range of values The same applies to non-recited values.
  • the particle size of the silicon powder is less than 3 ⁇ m, for example, it can be 0.5 ⁇ m, 1 ⁇ m, 1.5 ⁇ m, 2 ⁇ m, 2.5 ⁇ m, 2.7 ⁇ m or 2.8 ⁇ m, but is not limited to the listed values, and other values are not listed within the numerical range The same value applies.
  • the mass percentage content of silicon in the mixed powder is 50-70 wt %, for example, it can be 50 wt %, 55 wt %, 60 wt %, 65 wt % or 70 wt %, but not limited to the listed values, the numerical range The same applies to other non-recited values. .
  • the mixing in step (1) is mixing in a ball mill.
  • the grinding balls used for mixing in the ball mill are silicon balls and/or chrome balls.
  • the ratio of material to ball during mixing in the ball mill is (8-12):1, such as 8:1, 9:1, 10:1, 11:1 or 12:1, but not limited to those listed The same applies to other non-recited values within the numerical range.
  • the mixing time of step (1) is at least 24h, for example, it can be 24h, 25h, 26h, 27h, 28h or 30h, but is not limited to the enumerated values, and other unenumerated values in the numerical range are also applicable. .
  • the mold loading in step (2) is to load the mixed powder into a graphite mold.
  • the flatness after the mold is installed in step (2) is ⁇ 0.5mm, for example, it can be 0.1mm, 0.2mm, 0.3mm, 0.4mm or 0.5mm, but not limited to the listed values, other values within the range of values The same applies to non-recited values.
  • the vacuum hot pressing sintering described in this application is carried out in a hot pressing sintering furnace.
  • the vacuum hot pressing sintering in step (2) includes the following steps:
  • the heating rate of the first temperature program in step (a) is 6-10°C/min, for example, it can be 6°C/min, 7°C/min, 8°C/min, 9°C/min or 10°C /min, but is not limited to the recited values, other non-recited values within the numerical range are equally applicable.
  • the heating end point of the first temperature program in step (a) is 950-1050°C, for example, it can be 950°C, 960°C, 970°C, 980°C, 990°C, 1000°C, 1010°C, 1020°C, 1030°C, 1040°C or 1050°C, but not limited to the recited values, other non-recited values within the numerical range also apply.
  • the time of the first incubation described in step (b) is 50-80min, such as can be 50min, 55min, 60min, 65min, 70min, 75min or 80min, but not limited to the enumerated values, other values are not limited within the range of values. The values listed also apply.
  • the heating rate of the second temperature program in step (b) is 3-6°C/min, for example, it can be 3°C/min, 3.5°C/min, 4°C/min, 4.5°C/min, 5°C /min, 5.5°C/min or 6°C/min, but not limited to the recited values, other unrecited values within the numerical range are equally applicable.
  • the temperature increase rate of the second temperature program is slower than the temperature increase rate of the first temperature program.
  • the heating end point of the second temperature program in step (b) is 1100-1300°C, for example, it can be 1100°C, 1110°C, 1120°C, 1130°C, 1140°C, 1150°C, 1160°C, 1170°C, 1180°C, 1190°C, 1200°C, 1220°C, 1240°C, 1250°C, 1270°C, 1280°C or 1300°C, but not limited to the recited values, other non-recited values within the range of values also apply.
  • the time of the second incubation in step (b) is at least 1h, for example, it can be 1h, 1.5h, 2h, 2.5h, 3h, 4h or 5h, but is not limited to the listed values, other values within the range of values The same applies to non-recited values.
  • the pressurization in step (c) is uniformly pressurized to 30MPa within 2h, and the temperature is constant during the pressurization process.
  • the time of the described heat preservation and pressure keeping in step (c) is 80-100min, such as 80min, 85min, 90min, 95min or 100min, but not limited to the enumerated numerical values, and other unenumerated numerical values in the numerical range are the same. Be applicable.
  • the preparation method comprises the following steps:
  • the vacuum hot pressing sintering in step (2) includes the following steps:
  • the preparation method described in the present application makes the preparation method especially suitable for the chromium-silicon alloy sputtering target with a large amount of silicon by adjusting the mixing method of chromium powder and silicon powder and the specific operation of vacuum hot-pressing sintering.
  • the density of the chromium-silicon alloy sputtering target is ⁇ 99%, and the microscopically uniform and dense, without voids and layered structure, can improve the good performance guarantee for subsequent sputtering use.
  • the present embodiment provides a method for preparing a chromium-silicon alloy sputtering target, and the preparation method includes the following steps:
  • the vacuum hot pressing sintering in step (2) includes the following steps:
  • the present embodiment provides a method for preparing a chromium-silicon alloy sputtering target, and the preparation method includes the following steps:
  • the vacuum hot pressing sintering in step (2) includes the following steps:
  • the present embodiment provides a method for preparing a chromium-silicon alloy sputtering target, and the preparation method includes the following steps:
  • the vacuum hot pressing sintering in step (2) includes the following steps:
  • the present embodiment provides a method for preparing a chromium-silicon alloy sputtering target, and the preparation method includes the following steps:
  • the vacuum hot pressing sintering in step (2) includes the following steps:
  • the present embodiment provides a method for preparing a chromium-silicon alloy sputtering target, and the preparation method includes the following steps:
  • the vacuum hot pressing sintering in step (2) includes the following steps:
  • This embodiment provides a method for preparing a chromium-silicon alloy sputtering target, which is the same as that in Embodiment 1, except that the mixing in step (1) does not add grinding balls.
  • This embodiment provides a method for preparing a chromium-silicon alloy sputtering target, which is the same as that in Embodiment 1 except that the mixing time in step (1) is 20 hours.
  • This embodiment provides a method for preparing a chromium-silicon alloy sputtering target, which is the same as that of Embodiment 1 except that the pressure in the first temperature-programmed process of step (a) is 6-10 MPa.
  • This embodiment provides a method for preparing a chromium-silicon alloy sputtering target, which is the same as that in Embodiment 1 except that the heating rate of the first temperature program in step (a) is 12°C/min.
  • This embodiment provides a method for preparing a chromium-silicon alloy sputtering target, which is the same as that in Embodiment 1 except that the temperature increase rate of the second temperature program in step (b) is 8°C/min.
  • the present embodiment provides a method for preparing a chromium-silicon alloy sputtering target, and the preparation method includes the following steps:
  • the vacuum hot pressing sintering in step (2) includes the following steps:
  • Example 1 99.9 Microscopically uniform and dense, without voids and layered structures
  • Example 2 99.7 Microscopically uniform and dense, without voids and layered structures
  • Example 3 99.8 Microscopically uniform and dense, without voids and layered structures
  • Example 4 99.6 Microscopically uniform and dense, without voids and layered structures
  • Example 5 99.7 Microscopically uniform and dense, without voids and layered structures
  • Example 6 97.8 Inhomogeneous microstructure with voids
  • Example 7 95.4
  • Example 8 87.9 The obtained target is microscopically non-uniform and has cracking phenomenon
  • Example 9 86.3 The obtained target is microscopically non-uniform and has cracking phenomenon
  • Example 10 87.0 The obtained target is microscopically non-uniform and has cracking phenomenon
  • Example 11 91.6 The obtained target is microscopically non-uniform and has cracking phenomenon
  • the density of the chromium-silicon alloy sputtering target prepared by the preparation method described in this application is ⁇ 99%, and the microscopically uniform and dense, free of voids and layered structures, which can improve good performance for subsequent sputtering use. Assure.
  • the preparation method described in this application is particularly suitable for the sputtering of chromium-silicon alloys containing a large amount of silicon by adjusting the mixing method of chromium powder and silicon powder and the specific operation of vacuum hot-pressing sintering.
  • the density of the prepared chromium-silicon alloy sputtering target is ⁇ 99%, and the microscopically uniform and dense, without voids and layered structure, can improve the good performance guarantee for subsequent sputtering use.

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Abstract

本文提供了一种铬硅合金溅射靶材的制备方法,所述制备方法包括如下步骤:(1)非氧化性气氛条件下混合铬粉与硅粉,得到混合粉料;(2)装模,对装模后的混合粉料进行真空热压烧结;(3)真空热压烧结结束后随炉冷却,得到所述铬硅合金溅射靶材。

Description

一种铬硅合金溅射靶材的制备方法 技术领域
本申请属于半导体技术领域,涉及一种溅射靶材的制备方法,例如涉及一种铬硅合金溅射靶材的制备方法。
背景技术
磁控溅射是一种利用带电粒子轰击靶材,使靶材原子从表面溢出并均匀沉积在基片上的镀膜工艺,磁控溅射具有溅射率高、基片温度低、基片与膜层之间结合力好和优异的膜层均匀性等优势,磁控溅射技术已经被广泛应用于集成电路、信息存储设备、液晶显示屏、激光存储器与电子控制器件等电子以及信息产业的制造过程中。
磁控溅射过程中所用靶材的质量是影响磁控溅射镀膜质量的关键因素之一,所以对于溅射靶材的质量要求高于传统材料行业的质量要求,溅射靶材的一般质量要求主要包括对于尺寸、平整度、纯度、成分含量、密度、晶粒尺寸与缺陷控制等方面的要求;此外,在面粗糙度、电阻值、晶粒尺寸均匀性、成分与组织均匀性、氧化物含量与尺寸、导磁率、超高密度与超细晶粒等方面,溅射靶材具有更高的质量要求或者特殊的质量要求。
硅铬合金溅射靶材是一种新型的溅射靶材,作为一种真空溅镀的良好导体,可以用于电子栅门材料以及电子薄膜领域。为了使硅铬合金溅射靶材在进行真空溅镀时发挥良好的性能,要求硅铬合金溅射靶材具有较高的致密度、较高的内部组织结构均匀性以及较好的机加工条件。
CN 105331939A公开了一种含硅合金靶材及其制备方法,所述制备方法包括如下步骤:(1)预合金粉末制备;(2)对所述预合金粉末进行冷等静压处理, 得到冷等静压压坯,并装入包套内;(3)对装入所述冷等静压压坯的包套进行脱气处理,得到脱气后的锭坯;(4)对所述脱气后的锭坯进行热等静压处理,得到压制后的锭坯,再去除包套得到压制后的坯料;(5)对压制后的坯料进行机加工处理,得到含硅合金靶材。但冷等静压所需压力较高,对制备设备有较高的要求。
CN 104419859A公开了一种铬铝硅合金靶材,其中铬的原子百分比为5-75%,铝的原子百分比为10-90%,硅的原子百分比为1-20%,所述铬铝硅合金靶材的制备方法包括如下步骤:(1)合金粉末的制备;(2)对制备好的所述合金粉末进行冷等静压处理;(3)对所述冷等静压处理后的料坯进行脱气处理;(4)对所述脱气处理后的料坯进行热等静压处理;(5)对热等静压处理后的料坯进行机加工,清洗后得到所需成品合金靶材。所述铬铝硅合金靶材的加工过程中仍然需要进行冷等静压处理,对设备的要求较高,不利于降低所述铬铝硅合金靶材的制造成本。
CN 111058004A公开了一种铬硅合金溅射靶材的制备方法,所述制备方法包括如下步骤:(1)将具有目标质量比例的铬硅合金粉末装入模具并封口,进行振实处理;(2)将步骤(1)振实后的模具进行脱气处理;(3)将步骤(2)脱气后的模具在1000-1350℃下进行热等静压处理,得到铬硅合金溅射靶材粗品;(4)将步骤(3)得到的铬硅合金溅射靶材粗品进行机加工,得到铬硅合金溅射靶材。所述制备方法通过简单的热等静压处理能够得到铬硅合金溅射靶材,但其致密度还需进一步进行提升。
对此,需要提供一种新的铬硅合金溅射靶材的制备方法,使该制备方法制备得到的溅射靶材致密度更高、内部组织结构更加致密。
发明内容
本申请的目的在于提供一种铬硅合金溅射靶材的制备方法,所述制备方法使制备得到的铬硅合金溅射靶材的致密度较高,且微观均匀致密,无空洞与分层结构,可以为后续溅射使用提高良好的性能保障。
为达此目的,本申请采用以下技术方案:
本申请提供了一种铬硅合金溅射靶材的制备方法,所述制备方法包括如下步骤:
(1)非氧化性气氛条件下混合铬粉与硅粉,得到混合粉料;
(2)装模,对装模后的混合粉料进行真空热压烧结;
(3)真空热压烧结结束后随炉冷却,得到所述铬硅合金溅射靶材。
可选地,步骤(1)所述非氧化性气氛包括氮气气氛和/或惰性气氛。
可选地,所述惰性气氛包括氦气气氛、氖气气氛、氩气气氛或氪气气氛中的任意一种或至少两种的组合。
本申请所述惰性气氛所用气体包括氦气、氖气、氩气或氪气中的任意一种或至少两种的组合,典型但非限制性的组合包括氦气与氖气的组合,氖气与氩气的组合,氩气与氪气的组合,氖气与氪气的组合,氦气与氩气的组合,氩气、氖气与氦气的组合,或氦气、氖气、氩气与氪气的组合。
可选地,所述铬粉的纯度≥99.95%,例如可以是99.95%、99.96%、99.97%、99.98%、99.99%、99.992%、99.994%、99.995%、99.996%、99.998%或99.999%,但不限于所列举的数值,数值范围内其它未列举的数值同样适用。
可选地,所述铬粉的粒径<45μm,例如可以是5μm、10μm、15μm、20μm、25μm、30μm、35μm、40μm或44μm,但不限于所列举的数值,数值范围内其 它未列举的数值同样适用。
可选地,所述硅粉的纯度≥99.99%,例如可以是99.99%、99.992%、99.994%、99.995%、99.996%、99.998%或99.999%,但不限于所列举的数值,数值范围内其它未列举的数值同样适用。
可选地,所述硅粉的粒径<3μm,例如可以是0.5μm、1μm、1.5μm、2μm、2.5μm、2.7μm或2.8μm,但不限于所列举的数值,数值范围内其它未列举的数值同样适用。
可选地,所述混合粉料中硅的质量百分含量为50-70wt%,例如可以是50wt%、55wt%、60wt%、65wt%或70wt%,但不限于所列举的数值,数值范围内其它未列举的数值同样适用。。
可选地,步骤(1)所述混合为在球磨机中进行混合。
可选地,球磨机中进行混合时的磨球为硅球和/或铬球。
可选地,球磨机中进行混合时的料球比为(8-12):1,例如可以是8:1、9:1、10:1、11:1或12:1,但不限于所列举的数值,数值范围内其它未列举的数值同样适用。
可选地,步骤(1)所述混合的时间为至少24h,例如可以是24h、25h、26h、27h、28h或30h,但不限于所列举的数值,数值范围内其它未列举的数值同样适用。
可选地,步骤(2)所述装模为将混合粉料装入石墨模具。
可选地,步骤(2)所述装模后的平面度≤0.5mm,例如可以是0.1mm、0.2mm、0.3mm、0.4mm或0.5mm,但不限于所列举的数值,数值范围内其它未列举的数值同样适用。
本申请所述真空热压烧结在热压烧结炉中进行。
可选地,步骤(2)所述真空热压烧结包括如下步骤:
(a)抽真空至绝对真空度100Pa以下,然后进行第一程序升温,第一程序升温过程中保证压力不超过5MPa;
(b)第一程序升温结束后进行第一保温,然后依次进行第二程序升温与第二保温;
(c)第二保温结束后进行加压,加压结束后保温保压。
可选地,步骤(a)所述第一程序升温的升温速率为6-10℃/min,例如可以是6℃/min、7℃/min、8℃/min、9℃/min或10℃/min,但不限于所列举的数值,数值范围内其它未列举的数值同样适用。
可选地,步骤(a)所述第一程序升温的升温终点为950-1050℃,例如可以是950℃、960℃、970℃、980℃、990℃、1000℃、1010℃、1020℃、1030℃、1040℃或1050℃,但不限于所列举的数值,数值范围内其它未列举的数值同样适用。
可选地,步骤(b)所述第一保温的时间为50-80min,例如可以是50min、55min、60min、65min、70min、75min或80min,但不限于所列举的数值,数值范围内其它未列举的数值同样适用。
可选地,步骤(b)所述第二程序升温的升温速率为3-6℃/min,例如可以是3℃/min、3.5℃/min、4℃/min、4.5℃/min、5℃/min、5.5℃/min或6℃/min,但不限于所列举的数值,数值范围内其它未列举的数值同样适用。
可选地,所述第二程序升温的升温速率慢于第一程序升温的升温速率。
可选地,步骤(b)所述第二程序升温的升温终点为1100-1300℃,例如可 以是1100℃、1110℃、1120℃、1130℃、1140℃、1150℃、1160℃、1170℃、1180℃、1190℃、1200℃、1220℃、1240℃、1250℃、1270℃、1280℃或1300℃,但不限于所列举的数值,数值范围内其它未列举的数值同样适用。
可选地,步骤(b)所述第二保温的时间为至少1h,例如可以是1h、1.5h、2h、2.5h、3h、4h或5h,但不限于所列举的数值,数值范围内其它未列举的数值同样适用。
可选地,步骤(c)所述加压为在2h内均匀加压至30MPa,加压过程中温度恒定。
可选地,步骤(c)所述保温保压的时间为80-100min,例如可以是80min、85min、90min、95min或100min,但不限于所列举的数值,数值范围内其它未列举的数值同样适用。
作为本申请所述制备方法的可选技术方案,所述制备方法包括如下步骤:
(1)非氧化性气氛条件下混合粒径<45μm的铬粉与粒径<3μm的硅粉,得到混合粉料;所述混合粉料中硅的质量百分含量为50-70wt%;
(2)石墨模具中装模至平面度≤0.5mm,对装模后的混合粉料进行真空热压烧结;
(3)真空热压烧结结束后随炉冷却,得到所述铬硅合金溅射靶材;
步骤(2)所述真空热压烧结包括如下步骤:
(a)抽真空至绝对真空度100Pa以下,然后进行第一程序升温,第一程序升温过程中保证压力不超过5MPa;所述第一程序升温为以6-10℃/min的升温速率升高至950-1050℃;
(b)第一程序升温结束后保温50-80min,然后依次进行第二程序升温与第 二保温;所述第二程序升温为以3-6℃/min的升温速率升高至1100-1300℃;所述第二保温的时间为至少1h;
(c)第二保温结束后在2h内均匀加压至30MPa,加压过程中温度恒定,加压结束后保温保压80-100min。
本申请所述的数值范围不仅包括上述例举的点值,还包括没有例举出的上述数值范围之间的任意的点值,限于篇幅及出于简明的考虑,本申请不再穷尽列举所述范围包括的具体点值。
与现有技术相比,本申请的有益效果为:
本申请所述制备方法通过对铬粉与硅粉的混合方法以及真空热压烧结具体操作的调整,使所述制备方法特别适用于含硅量较多的铬硅合金溅射靶材,制备得到的铬硅合金溅射靶材的致密度≥99%,且微观均匀致密,无空洞与分层结构,可以为后续溅射使用提高良好的性能保障。
具体实施方式
下面通过具体实施方式来进一步说明本申请的技术方案。
实施例1
本实施例提供了一种铬硅合金溅射靶材的制备方法,所述制备方法包括如下步骤:
(1)氮气气氛条件下混合粒径<45μm的铬粉与粒径<3μm的硅粉,得到混合粉料;所述混合粉料中硅的质量百分含量为60wt%;铬粉的纯度≥99.95wt%,硅粉的纯度≥99.99wt%;混合为在球磨机中进行混合,混合时的磨球为硅球,混合时的料球比为10:1,混合时间为24h;
(2)石墨模具中装模至平面度≤0.5mm,对装模后的混合粉料进行真空热 压烧结;
(3)真空热压烧结结束后进行自然冷却,得到所述铬硅合金溅射靶材;
步骤(2)所述真空热压烧结包括如下步骤:
(a)抽真空至绝对真空度100Pa以下,然后进行第一程序升温,第一程序升温过程中保证压力不超过5MPa;所述第一程序升温为以8℃/min的升温速率升高至1000℃;
(b)第一程序升温结束后保温65min,然后依次进行第二程序升温与第二保温;所述第二程序升温为以4℃/min的升温速率升高至1150℃;所述第二保温的时间为1h;
(c)第二保温结束后在2h内均匀加压至30MPa,加压过程中温度恒定,加压结束后保温保压90min。
实施例2
本实施例提供了一种铬硅合金溅射靶材的制备方法,所述制备方法包括如下步骤:
(1)氦气气氛条件下混合粒径<45μm的铬粉与粒径<3μm的硅粉,得到混合粉料;所述混合粉料中硅的质量百分含量为55wt%;铬粉的纯度≥99.95wt%,硅粉的纯度≥99.99wt%;混合为在球磨机中进行混合,混合时的磨球为硅球,混合时的料球比为9:1,混合时间为24h;
(2)石墨模具中装模至平面度≤0.5mm,对装模后的混合粉料进行真空热压烧结;
(3)真空热压烧结结束后进行自然冷却,得到所述铬硅合金溅射靶材;
步骤(2)所述真空热压烧结包括如下步骤:
(a)抽真空至绝对真空度100Pa以下,然后进行第一程序升温,第一程序升温过程中保证压力不超过5MPa;所述第一程序升温为以7℃/min的升温速率升高至980℃;
(b)第一程序升温结束后保温70min,然后依次进行第二程序升温与第二保温;所述第二程序升温为以4℃/min的升温速率升高至1120℃;所述第二保温的时间为1h;
(c)第二保温结束后在2h内均匀加压至30MPa,加压过程中温度恒定,加压结束后保温保压85min。
实施例3
本实施例提供了一种铬硅合金溅射靶材的制备方法,所述制备方法包括如下步骤:
(1)氖气气氛条件下混合粒径<45μm的铬粉与粒径<3μm的硅粉,得到混合粉料;所述混合粉料中硅的质量百分含量为65wt%;铬粉的纯度≥99.95wt%,硅粉的纯度≥99.99wt%;混合为在球磨机中进行混合,混合时的磨球为硅球,混合时的料球比为11:1,混合时间为24h;
(2)石墨模具中装模至平面度≤0.5mm,对装模后的混合粉料进行真空热压烧结;
(3)真空热压烧结结束后进行自然冷却,得到所述铬硅合金溅射靶材;
步骤(2)所述真空热压烧结包括如下步骤:
(a)抽真空至绝对真空度100Pa以下,然后进行第一程序升温,第一程序升温过程中保证压力不超过5MPa;所述第一程序升温为以9℃/min的升温速率升高至1020℃;
(b)第一程序升温结束后保温60min,然后依次进行第二程序升温与第二保温;所述第二程序升温为以5℃/min的升温速率升高至1180℃;所述第二保温的时间为1h;
(c)第二保温结束后在2h内均匀加压至30MPa,加压过程中温度恒定,加压结束后保温保压95min。
实施例4
本实施例提供了一种铬硅合金溅射靶材的制备方法,所述制备方法包括如下步骤:
(1)氩气气氛条件下混合粒径<45μm的铬粉与粒径<3μm的硅粉,得到混合粉料;所述混合粉料中硅的质量百分含量为50wt%;铬粉的纯度≥99.95wt%,硅粉的纯度≥99.99wt%;混合为在球磨机中进行混合,混合时的磨球为铬球,混合时的料球比为8:1,混合时间为24h;
(2)石墨模具中装模至平面度≤0.5mm,对装模后的混合粉料进行真空热压烧结;
(3)真空热压烧结结束后进行自然冷却,得到所述铬硅合金溅射靶材;
步骤(2)所述真空热压烧结包括如下步骤:
(a)抽真空至绝对真空度100Pa以下,然后进行第一程序升温,第一程序升温过程中保证压力不超过5MPa;所述第一程序升温为以6℃/min的升温速率升高至950℃;
(b)第一程序升温结束后保温80min,然后依次进行第二程序升温与第二保温;所述第二程序升温为以3℃/min的升温速率升高至1100℃;所述第二保温的时间为1h;
(c)第二保温结束后在2h内均匀加压至30MPa,加压过程中温度恒定,加压结束后保温保压100min。
实施例5
本实施例提供了一种铬硅合金溅射靶材的制备方法,所述制备方法包括如下步骤:
(1)氪气气氛条件下混合粒径<45μm的铬粉与粒径<3μm的硅粉,得到混合粉料;所述混合粉料中硅的质量百分含量为70wt%;铬粉的纯度≥99.95wt%,硅粉的纯度≥99.99wt%;混合为在球磨机中进行混合,混合时的磨球为铬球,混合时的料球比为12:1,混合时间为24h;
(2)石墨模具中装模至平面度≤0.5mm,对装模后的混合粉料进行真空热压烧结;
(3)真空热压烧结结束后进行自然冷却,得到所述铬硅合金溅射靶材;
步骤(2)所述真空热压烧结包括如下步骤:
(a)抽真空至绝对真空度100Pa以下,然后进行第一程序升温,第一程序升温过程中保证压力不超过5MPa;所述第一程序升温为以10℃/min的升温速率升高至1050℃;
(b)第一程序升温结束后保温50min,然后依次进行第二程序升温与第二保温;所述第二程序升温为以6℃/min的升温速率升高至1300℃;所述第二保温的时间为1h;
(c)第二保温结束后在2h内均匀加压至30MPa,加压过程中温度恒定,加压结束后保温保压80min。
实施例6
本实施例提供了一种铬硅合金溅射靶材的制备方法,除步骤(1)所述混合未添加磨球外,其余均与实施例1相同。
实施例7
本实施例提供了一种铬硅合金溅射靶材的制备方法,除步骤(1)所述混合的时间为20h外,其余均与实施例1相同。
实施例8
本实施例提供了一种铬硅合金溅射靶材的制备方法,除步骤(a)所述第一程序升温过程中压力为6-10MPa外,其余均与实施例1相同。
实施例9
本实施例提供了一种铬硅合金溅射靶材的制备方法,除步骤(a)所述第一程序升温的升温速率为12℃/min外,其余均与实施例1相同。
实施例10
本实施例提供了一种铬硅合金溅射靶材的制备方法,除步骤(b)所述第二程序升温的升温速率为8℃/min外,其余均与实施例1相同。
实施例11
本实施例提供了一种铬硅合金溅射靶材的制备方法,所述制备方法包括如下步骤:
(1)氮气气氛条件下混合粒径<45μm的铬粉与粒径<3μm的硅粉,得到混合粉料;所述混合粉料中硅的质量百分含量为60wt%;铬粉的纯度≥99.95wt%,硅粉的纯度≥99.99wt%;混合为在球磨机中进行混合,混合时的磨球为硅球,混合时的料球比为10:1,混合时间为24h;
(2)石墨模具中装模至平面度≤0.5mm,对装模后的混合粉料进行真空热 压烧结;
(3)真空热压烧结结束后随炉冷却,得到所述铬硅合金溅射靶材;
步骤(2)所述真空热压烧结包括如下步骤:
(I)抽真空至绝对真空度100Pa以下,然后进行第一程序升温,第一程序升温过程中保证压力不超过5MPa;所述第一程序升温为以8℃/min的升温速率升高至1150℃,保温1h;
(II)保温结束后在2h内均匀加压至30MPa,加压过程中温度恒定,加压结束后保温保压90min。
对实施例1-11提供个铬硅合金溅射靶材的致密度以及内部组织结构均匀度进行测试,测试结果如表1所示。
表1
  致密度/% 内部组织结构均匀性
实施例1 99.9 微观均匀致密,无空洞与分层结构
实施例2 99.7 微观均匀致密,无空洞与分层结构
实施例3 99.8 微观均匀致密,无空洞与分层结构
实施例4 99.6 微观均匀致密,无空洞与分层结构
实施例5 99.7 微观均匀致密,无空洞与分层结构
实施例6 97.8 微观组织不均匀,存在空洞
实施例7 95.4 微观组织不均匀,存在空洞
实施例8 87.9 所得靶材微观不均匀,且存在开裂现象
实施例9 86.3 所得靶材微观不均匀,且存在开裂现象
实施例10 87.0 所得靶材微观不均匀,且存在开裂现象
实施例11 91.6 所得靶材微观不均匀,且存在开裂现象
由表1可知,本申请所述制备方法制备得到的铬硅合金溅射靶材的致密度≥99%,且微观均匀致密,无空洞与分层结构,可以为后续溅射使用提高良好的性能保障。
综上所述,本申请所述制备方法通过对铬粉与硅粉的混合方法以及真空热压烧结具体操作的调整,使所述制备方法特别适用于含硅量较多的铬硅合金溅射靶材,制备得到的铬硅合金溅射靶材的致密度≥99%,且微观均匀致密,无空洞与分层结构,可以为后续溅射使用提高良好的性能保障。
以上所述的具体实施例,对本申请的目的、技术方案和有益效果进行了进一步详细说明,所应理解的是,以上所述仅为本申请的具体实施例而已,并不用于限制本申请。

Claims (12)

  1. 一种铬硅合金溅射靶材的制备方法,其包括如下步骤:
    (1)非氧化性气氛条件下混合铬粉与硅粉,得到混合粉料;
    (2)装模,对装模后的混合粉料进行真空热压烧结;
    (3)真空热压烧结结束后随炉冷却,得到所述铬硅合金溅射靶材。
  2. 根据权利要求1所述的制备方法,其中,所述铬粉的纯度≥99.95%。
  3. 根据权利要求1或2所述的制备方法,其中,所述混合粉料中硅的质量百分含量为50-70wt%。
  4. 根据权利要求1-3任一项所述的制备方法,其中,所述铬粉的粒径<45μm;
    可选地,所述硅粉的纯度≥99.99%;
    可选地,所述硅粉的粒径<3μm。
  5. 根据权利要求1-4任一项所述的制备方法,其中,步骤(1)所述非氧化性气氛包括氮气气氛和/或惰性气氛;
    可选地,所述惰性气氛包括氦气气氛、氖气气氛、氩气气氛或氪气气氛中的任意一种或至少两种的组合。
  6. 根据权利要求1-5任一项所述的制备方法,其中,步骤(1)所述混合为在球磨机中进行混合;
    可选地,球磨机中进行混合时的磨球为硅球和/或铬球;
    可选地,球磨机中进行混合时的料球比为(8-12):1;
    可选地,步骤(1)所述混合的时间为至少24h。
  7. 根据权利要求1-6任一项所述的制备方法,其中,步骤(2)所述装模为将混合粉料装入石墨模具;
    可选地,步骤(2)所述装模后的平面度≤0.5mm。
  8. 根据权利要求1-7任一项所述的制备方法,其中,步骤(2)所述真空热压烧结包括如下步骤:
    (a)抽真空至绝对真空度100Pa以下,然后进行第一程序升温,第一程序升温过程中保证压力不超过5MPa;
    (b)第一程序升温结束后进行第一保温,然后依次进行第二程序升温与第二保温;
    (c)第二保温结束后进行加压,加压结束后保温保压。
  9. 根据权利要求8所述的制备方法,其中,步骤(a)所述第一程序升温的升温速率为6-10℃/min;
    可选地,步骤(a)所述第一程序升温的升温终点为950-1050℃。
  10. 根据权利要求8或9所述的制备方法,其中,步骤(b)所述第一保温的时间为50-80min;
    可选地,步骤(b)所述第二程序升温的升温速率为3-6℃/min;
    可选地,步骤(b)所述第二程序升温的升温终点为1100-1300℃;
    可选地,步骤(b)所述第二保温的时间为至少1h。
  11. 根据权利要求8-10任一项所述的制备方法,其中,步骤(c)所述加压为在2h内均匀加压至30MPa,加压过程中温度恒定;
    可选地,步骤(c)所述保温保压的时间为80-100min。
  12. 根据权利要求1-11任一项所述的制备方法,其包括如下步骤:
    (1)非氧化性气氛条件下混合粒径<45μm的铬粉与粒径<3μm的硅粉,得到混合粉料;所述混合粉料中硅的质量百分含量为50-70wt%;
    (2)石墨模具中装模至平面度≤0.5mm,对装模后的混合粉料进行真空热压烧结;
    (3)真空热压烧结结束后随炉冷却,得到所述铬硅合金溅射靶材;
    步骤(2)所述真空热压烧结包括如下步骤:
    (a)抽真空至绝对真空度100Pa以下,然后进行第一程序升温,第一程序升温过程中保证压力不超过5MPa;所述第一程序升温为以6-10℃/min的升温速率升高至950-1050℃;
    (b)第一程序升温结束后保温50-80min,然后依次进行第二程序升温与第二保温;所述第二程序升温为以3-6℃/min的升温速率升高至1100-1300℃;所述第二保温的时间为至少1h;
    (c)第二保温结束后在2h内均匀加压至30MPa,加压过程中温度恒定,加压结束后保温保压80-100min。
PCT/CN2021/086058 2020-11-04 2021-04-09 一种铬硅合金溅射靶材的制备方法 WO2022095336A1 (zh)

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