WO2020087723A1 - 一种碳化硅单晶生长装置 - Google Patents

一种碳化硅单晶生长装置 Download PDF

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WO2020087723A1
WO2020087723A1 PCT/CN2018/123717 CN2018123717W WO2020087723A1 WO 2020087723 A1 WO2020087723 A1 WO 2020087723A1 CN 2018123717 W CN2018123717 W CN 2018123717W WO 2020087723 A1 WO2020087723 A1 WO 2020087723A1
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silicon carbide
single crystal
carbide single
crystal growth
container
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PCT/CN2018/123717
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English (en)
French (fr)
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梁晓亮
宁秀秀
高超
李霞
宗艳民
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山东天岳先进材料科技有限公司
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Priority claimed from CN201821809418.7U external-priority patent/CN209144310U/zh
Priority claimed from CN201811302583.8A external-priority patent/CN109234797B/zh
Application filed by 山东天岳先进材料科技有限公司 filed Critical 山东天岳先进材料科技有限公司
Publication of WO2020087723A1 publication Critical patent/WO2020087723A1/zh

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    • C—CHEMISTRY; METALLURGY
    • C30—CRYSTAL GROWTH
    • C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
    • C30B23/00—Single-crystal growth by condensing evaporated or sublimed materials
    • C—CHEMISTRY; METALLURGY
    • C30—CRYSTAL GROWTH
    • C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
    • C30B29/00—Single crystals or homogeneous polycrystalline material with defined structure characterised by the material or by their shape
    • C30B29/10—Inorganic compounds or compositions
    • C30B29/36—Carbides

Definitions

  • the present application belongs to the field of crystal growth, and specifically relates to a silicon carbide single crystal growth device.
  • Silicon carbide single crystal is one of the most important third-generation semiconductor materials. Because of its excellent properties such as wide band gap, high saturation electron mobility, strong breakdown field, and high thermal conductivity, it is widely used in power electronics, RF devices, optoelectronic devices and other fields.
  • High-purity silicon carbide single crystal is the material of choice for the preparation of high-frequency, high-power microwave devices, but high-purity semi-insulating silicon carbide single crystal has high purity requirements, so the single crystal preparation technology is difficult and the production cost is high.
  • the main reason for the high production cost is that the size of the SiC single crystal ingot is limited during the growth process.
  • the most mature method that can achieve mass production of SiC single crystal is the PVT method, that is, the gas phase source generated by sublimating the silicon carbide raw material is transported to the seed crystal at high temperature and recrystallized.
  • SiC single crystal due to the low melting point of Si component, it will preferentially evaporate and sublimate, and penetrate outward through the wall of the graphite crucible. As the reaction progresses, the Si / C ratio gradually decreases, and the single crystal Growth defects increase and quality decreases, so that the size of available ingots cannot continue to increase, thereby limiting the growth and cost reduction of high-quality single crystals. .
  • the growth process of growing the silicon carbide single crystal by the PVT method is carried out in a sealed graphite crucible, so the growth environment is under a carbon-rich atmosphere at high temperatures.
  • the crystal growth interface is in a state where the silicon component and the carbon component are in equilibrium.
  • the silicon component in the silicon carbide raw material continues to sublimate and reduce, resulting in the gas phase component in the growth chamber gradually becoming unbalanced and becoming a carbon-rich state, and the growth end generally occurs at the bottom of the raw material area and near the bottom of the crucible wall Severely carbonized.
  • the frontier interface of crystal growth will be enriched with carbon and form carbon inclusion defects.
  • the inclusions can in turn induce defects such as microtubes, dislocations, and stacking faults, which seriously affect the quality of the silicon carbide substrate and thus the quality of the epitaxial layer and device performance.
  • Avinash K Gupta et al. Proposed to add solid silicon oxide (such as solid SiO or SiO 2 ) in the growth chamber in order to act as a crystal growth process A supplementary source of silicon components, thereby reducing the formation of carbon-rich components and thereby inhibiting the formation of carbon inclusions [US 2008/0115719 A1].
  • this method cannot sufficiently suppress the carbonization of the silicon carbide raw material, resulting in a higher concentration of carbon inclusion defects in the later stage of crystal growth, resulting in a significant decrease in crystal quality and substrate quality.
  • the technique proposed by Avinash K Gupta et al. To add solid silicon oxide in the growth chamber to supplement the silicon component will introduce additional impurities, resulting in unstable fluctuations in the concentration of impurities in the crystal, which may affect the silicon carbide lining Conductivity of the bottom.
  • JP4962205B2 a silicon carbide single crystal production device and method are disclosed to promote the growth rate of SiC single crystal, extend the growth time of SiC single crystal, and reduce the residual amount of SiC powder raw material.
  • the device is provided with a number of porous hollow tubes in the crucible.
  • the porous hollow tubes provide an ascending channel for the sublimation of the SiC powder under heat, and the generated sublimation gas passes through the porous tube to the space area above the crucible.
  • This technical solution essentially reduces the growth time of SiC and increases its growth rate, but it does not have the ability to adjust Si / C for the conversion of SiC raw materials to single crystals.
  • JP2010280546A a method for producing silicon carbide single crystals is disclosed.
  • the method is to bury silicon carbide single crystals in a crucible in a mixed powder of carbon and silicon carbide for annealing treatment under high temperature conditions to suppress the accompanying carbonization.
  • the occurrence of defects can reduce the problem of silicon carbide crystal defects caused during the crystal synthesis process, it is not solved during the growth of silicon carbide.
  • a silicon carbide single crystal growth device including a growth chamber for placing raw materials and providing a place where raw materials are sublimated by heating.
  • the growth chamber is divided into a raw material section where raw materials are placed And a gas circulation area for the sublimation and crystallization of raw materials; a plurality of thermally conductive containers are provided in the growth chamber, the thermally conductive containers are provided in the raw material portion, and the thermally conductive containers are isolated from the inner wall of the growth chamber.
  • the heat-conducting container is used for placing supplementary substances, the supplementary substances containing at least silicon element and carbon element, and the molar ratio of carbon to silicon is 0-1: 1, preferably 0-0.5: 1.
  • the provision of a heat-conducting container in the growth chamber is on the one hand to place substances that need to be replenished in the heat-conducting container.
  • the Si / C ratio will be unbalanced during the growth of silicon carbide single crystals, in a carbon-rich growth environment, The front of the crystal growth interface will be enriched with carbon and form carbon inclusion defects, so this application places Si powder or a mixture of Si powder and SiC powder in the thermally conductive container to supplement the silicon component and adjust the Si / C ratio
  • the thermally conductive container has thermal conductivity, the temperature field distribution of the raw material part can be adjusted in the growth chamber to reduce the carbonization of the raw material.
  • the Si element replenishment device may be elemental Si powder or a mixture of elemental Si powder and SIC powder, but the mass ratio of elemental Si powder to the entire system of SiC powder must be maintained.
  • a mixture of Si powder and SiC powder is preferred, which can reduce the direct contact between Si powder and the inner wall of the replenishment device and premature reaction.
  • the weight of Si powder is calculated according to the mass ratio, and the amount of SiC powder is preferably filled with Si element replenishment device.
  • the thermally conductive container includes a container body and a container lid.
  • the cover of the container is set to make it more convenient to take and place supplementary substances.
  • a graphite layer is provided in the through hole.
  • the container body and / or the container lid are provided with several through holes.
  • the setting of the through hole is to facilitate the transmission of the gas phase after the Si powder and the SiC powder in the container body are sublimated by heating, and it is more convenient to supplement the silicon component in the raw material.
  • the thermally conductive container is a crucible made of tantalum material or a crucible made of tantalum-plated graphite material. Since the Si powder sublimates into the gas phase under high temperature and high pressure, it has an erosive effect on the graphite crucible. If the thermally conductive container is a tantalum crucible or a tantalum-plated graphite crucible, the erosion of the crucible is well avoided, and it grows on the silicon carbide single crystal After the end, it can be taken out by a certain method to achieve reuse and reduce costs.
  • the thermally conductive container is a graphite crucible, and a graphite crucible cover is provided on the graphite crucible.
  • the thermally conductive container is a graphite crucible, which mainly uses Si powder to sublimate into a gas phase under high temperature and high pressure, which has an erosive effect on the graphite crucible, thereby achieving the release of Si elements into the raw material, and continuously supplementing the raw material as the growth process proceeds Si component.
  • a plurality of erosion parts are provided in the heat conduction container, the wall thickness of the erosion part is smaller than the average wall thickness of the graphite crucible, and the wall thickness of the erosion part is smaller than the average thickness of the graphite crucible cover.
  • the Si powder in the thermally conductive container begins to liquefy and begins to react with the graphite crucible wall.
  • the thinnest part of the thermally conductive container wall is first completely eroded by the Si component. The Si element is released into the raw material, and the Si component is continuously replenished to the raw material as the growth process proceeds.
  • the shape of the erosion space formed by the erosion portion is a cone or a truncated cone, and the bottom surface of the cone or the truncated cone is disposed away from the outer wall of the heat conduction container.
  • the erosion space is located at the bottom of the thermally conductive container.
  • the Si powder first erodes the bottom of the thermally conductive container when heated, and the Si component releases Si elements from the bottom of the thermally conductive container to the raw material.
  • the heat-conducting container is provided in the middle region of the bottom of the raw material part or the region near the side wall of the growth chamber. This setting is for the heat-conducting container to better regulate the thermal field in the raw material area.
  • the thermally conductive container is a small crucible
  • the growth chamber is an outer crucible.
  • the device for silicon carbide single crystal growth includes an outer crucible, and an insulation heating device is provided outside the outer crucible.
  • the outer crucible is divided into a raw material portion where raw materials are placed and a gas circulation area for the sublimation and crystallization of raw materials;
  • a plurality of small crucibles are provided in the outer crucible, the small crucibles are provided in the raw material part, and the small crucibles are isolated from the inner wall of the outer crucible;
  • the small crucible includes a container body and a container cover; the small crucible is provided in the raw material part The middle area of the bottom or the area near the side wall of the outer crucible.
  • This application can effectively adjust the Si / C ratio in the growth chamber of silicon carbide single crystal growth, thereby reducing the carbon inclusion defects generated by single crystal growth;
  • This application can effectively adjust the temperature field distribution in the raw material area and reduce the carbonization of raw materials
  • This application has the characteristics of simple operation, strong security, strong practicability, and suitable for promotion and use.
  • FIG. 1 is a schematic structural view of a silicon carbide single crystal growth device
  • Figure 2 is a schematic diagram of the structure of the container cover of the thermally conductive container
  • FIG. 3 is a schematic structural diagram of another thermally conductive container.
  • first and second are used for description purposes only, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated.
  • the features defined as “first” and “second” may explicitly or implicitly include one or more of the features.
  • the meaning of “plurality” is two or more, unless otherwise specifically limited.
  • the terms “installation”, “connected”, “connected”, “fixed” and other terms should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection , Or integrated; it can be mechanical connection, electrical connection, or communication; it can be directly connected or indirectly connected through an intermediary, it can be the connection between two components or the interaction between two components .
  • installation can be a fixed connection or a detachable connection , Or integrated; it can be mechanical connection, electrical connection, or communication; it can be directly connected or indirectly connected through an intermediary, it can be the connection between two components or the interaction between two components .
  • the first feature is “on” or “under” the second feature may be that the first and second features are in direct contact, or the first and second features are indirectly through an intermediary contact.
  • the description referring to the terms “one embodiment”, “some embodiments”, “examples”, “specific examples”, or “some examples” means specific features described in conjunction with the embodiment or examples , Structure, material or characteristic is included in at least one embodiment or example of the present application.
  • the schematic representation of the above terms does not necessarily refer to the same embodiment or example.
  • the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.
  • Example 1 Silicon carbide single crystal growth device:
  • the present application provides a silicon carbide single crystal growth device, including: a growth chamber 1, which is used for placing raw materials, and provides a place where raw materials are sublimated by heating, and the growth chamber 1 is divided into raw materials for placing raw materials The portion 11 and the gas circulation area 12 for the sublimation and crystallization of the raw materials; the growth chamber 1 is a crucible or other container that can realize the growth of silicon carbide.
  • the raw material portion 11 and the gas circulation area 12 may be the upper and lower parts of a closed space, for example: growth
  • the cavity 1 is a crucible
  • the raw material portion 11 is an area where raw materials are placed at the bottom of the inner cavity of the crucible
  • the gas circulation area 12 is a gas-phase space without raw materials in the upper part of the crucible
  • the raw material portion 11 and the gas circulation area 12 may also be separate components, Other distribution methods that can be realized by those skilled in the art.
  • a plurality of heat-conducting containers 111 are provided in the growth chamber 1.
  • the heat-conducting containers 111 are provided in the raw material portion 11.
  • the heat-conducting containers 111 are isolated from the inner wall of the growth chamber 1. Wall area. As to how many heat-conducting containers 111 are placed, it depends on the amount of raw materials placed and the size of the growth chamber 1.
  • the thermally conductive container 111 in this embodiment includes a container body and a container cover 112. As shown in FIG. 2, the container body and / or the container cover 112 are provided with a plurality of through holes 113.
  • the thermally conductive container 111 is a crucible made of tantalum or tantalum-plated graphite.
  • the material of the thermally conductive container 111 in this embodiment is not limited to tantalum or
  • the tantalum-plated graphite material can be any material that can satisfy thermal conductivity and is not corroded by Si powder at high temperatures.
  • a graphite seal needs to be provided on the through hole 113 to delay the rate of Si powder loss and control the release time.
  • this application provides another thermally conductive container 111.
  • the thermally conductive container 111 is a graphite crucible.
  • the thermally conductive container 111 is not limited to graphite material, as long as it can conduct heat and can be powdered by Si at high temperature. Erosion will do.
  • a graphite crucible cover 114 is provided on the graphite crucible, and the graphite crucible cover 114 is tightly fixed on the graphite crucible.
  • a plurality of erosion parts 115 are provided in the thermally conductive container 111.
  • the wall thickness of the erosion part 115 is smaller than the average wall thickness of the graphite crucible, and the wall thickness of the erosion part 115 is smaller than the average thickness of the graphite crucible cover 114.
  • the shape of the erosion space formed by the erosion portion 115 is a cone or a truncated cone, and the bottom surface of the cone or the truncated cone is disposed away from the outer wall of the heat conduction container 111.
  • the erosion space is located at the bottom of the thermally conductive container 111.
  • the heat-conducting container 111 is provided in the middle region of the bottom of the raw material part 11 or the region near the side wall of the growth chamber 1.
  • the shape and wall thickness of the eroded part 115 of the heat-conducting container 111 in this embodiment can be adjusted as needed, and parameters such as the shape and wall thickness of the eroded part 115 are determined according to the amount of Si component to be replenished and the replenishment rate.
  • Example 2 Growth method of silicon carbide single crystal:
  • the silicon carbide single crystal growth device is filled with silicon carbide raw materials and seed crystals, the silicon carbide raw material is buried in a number of thermally conductive containers, the thermally conductive container is filled with Si powder, the silicon carbide single crystal growth device is fixed on the heat source Into protective gas;
  • the pressure in the silicon carbide single crystal growth device is gradually reduced to the second pressure, and the furnace temperature is gradually increased to the second temperature;
  • the thermally conductive container may be a small crucible, and the growth chamber may be an outer crucible.
  • the Si element replenishment device is set in the high temperature zone of the raw material, where SiC powder is carbonized earlier.
  • Different setting schemes can be implemented according to the temperature distribution of the raw material, but it is necessary to ensure an even distribution of the set points at the same height.
  • the layout plan is as follows:
  • the test method for the concentration of inclusions is: select 10 grown crystals, observe the other inclusions under the microscope after slicing the crystal, and extract 10th and 20th pieces of each crystal uniformly, under 50 times magnification, statistics Concentration of inclusions.
  • the difference in thickness is: the average value of the difference between the maximum thickness and the minimum thickness of 10 crystals grown at the edges.
  • the number of microtubes is: select the number of large clusters of microtubes in 10 crystals grown.
  • the Si element supplement device is installed in the silicon carbide single crystal growth device, the carbon encapsulation concentration is significantly reduced, the thickness difference of the crystal edge and the number of microtubes are significantly reduced, indicating that through carbonization
  • a Si element replenishment device is provided in the silicon single crystal growth device, and Si powder or a mixture of Si powder and SiC powder is placed in the Si element replenishment device to supplement Si during the growth of silicon carbide and adjust the Si / C ratio so that the crystal quality obtained is obvious Increase; in addition, the use of a penetrating single crystal growth device is more difficult than the form of a single crystal growth device with a through hole, because under suitable conditions, you can control the Si element replenishment device leakage time and Si The time when the element replenishment device is destroyed can achieve better control effects and improve quality; while the single crystal growth device with through holes can control the leakage time, to a certain extent, it can control the time for Si element replenishment, so Compared with the ordinary silicon carb

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Abstract

本申请涉及一种碳化硅单晶生长装置，包括：生长腔，所述生长腔用于放置原料，并提供原料受热升华的场所，所述生长腔分为放置原料的原料部和供原料升华结晶的气体流通区域；所述生长腔中设置若干导热容器，所述导热容器设在原料部，所述导热容器与生长腔的内壁隔离设置。本申请可以有效的调节在碳化硅单晶生长中生长腔室中的Si/C比例，从而减少单晶生长产生的碳包裹体缺陷。

Description

一种碳化硅单晶生长装置 技术领域
本申请属于晶体生长领域，具体涉及一种碳化硅单晶生长装置。
背景技术
碳化硅单晶是最重要的第三代半导体材料之一，因其具有禁带宽度大、饱和电子迁移率高、击穿场强大、热导率高等优异性质，而被广泛应用于电力电子、射频器件、光电子器件等领域。
高纯碳化硅单晶是制备高频、大功率微波器件的首选材料，但高纯半绝缘碳化硅单晶由于其纯度要求较高，故而单晶制备技术难度大，生产成本高。而造成生产成本高的主要原因为SiC单晶晶锭的尺寸在生长过程受到限制。目前最为成熟可以实现SiC单晶量产的方法为PVT法，即在高温下使碳化硅原料升华产生的气相源输运至籽晶处重新结晶而成。在PVT法生长SiC单晶的过程中，由于Si组分的低熔点特性，会优先蒸发及升华，并通过石墨坩埚壁向外渗透，随着反应的进行，Si/C比例逐渐降低，单晶生长缺陷增加，质量下降，致使可用晶锭尺寸不能继续增加，从而限制了高品质单晶的生长及成本的降低。。
有相关专利及文献报道向原料中添加Si或SiO 2成分，来调节Si/C比例，但直接添加Si分同样存在Si较早挥发的问题，同Si蒸汽可能在开始长晶之前对籽晶造成侵蚀与破坏，而SiO 2中的氧可能与通入的气体(H 2)组分发生反应，或与C粉反应发生燃烧，对生长高纯SiC晶体产生不利影响。
另一方面，PVT法生长碳化硅单晶的生长过程在密闭的石墨坩埚中进 行，因此在高温下生长环境处于富碳气氛下。晶体生长初期，由于硅组分的蒸气分压较高，因此晶体生长界面处于硅组分和碳组分相平衡的状态。随着晶体生长的进行，碳化硅原料中的硅组分不断升华减少，导致生长腔室内的气相组分逐渐失衡成为富碳状态，且生长结束一般会在原料区的底部及靠近坩埚壁底部发生严重碳化。在富碳的生长环境下，晶体生长的前沿界面会有碳的富集并形成碳包裹体缺陷。包裹体进而会诱生微管、位错、层错等缺陷，严重影响到碳化硅衬底质量进而影响外延层质量和器件性能。
在现有技术中，为了消除PVT法生长碳化硅中的碳包裹体缺陷，Avinash K Gupta等提出在生长腔室内添加固态硅氧化物(如固态SiO或SiO 2)，以期在晶体生长过程中作为硅组分的补充源，从而减少富碳组分的生成，进而抑制碳包裹体的形成[US 2008/0115719 A1]。但是该方法无法充分抑制碳化硅原料的碳化，导致在晶体生长的后期出现较高浓度的碳包裹体缺陷，导致晶体质量和衬底质量大幅降低。Avinash K Gupta等提出的在生长腔室中加入固态硅氧化物以补充硅组分的技术，会引入额外的杂质，致使晶体中杂质浓度可能出现不稳定的波动，进而可能会影响到碳化硅衬底的导电性能。
在JP4962205B2中公开了一种碳化硅单晶生产装置和方法，以促进SiC单晶的生长速率，延长SiC单晶的生长时间，减少SiC粉末原料的残留量。该装置在坩埚中设置若干个多孔空心管，多孔空心管中为下部的SiC粉末受热升华提供上升通道，所产生的升华气体通过所述多孔管到坩埚上部的空间区域中。该技术方案实质上是降低SiC的生长时间，提高其 生长速度，但是其对于SiC原料向单晶的转化并不具有调节Si/C的能力。
在JP2010280546A中公开了一种生产碳化硅单晶的方法，该方法是在坩埚中将碳化硅单晶埋在碳和碳化硅混合粉中，用于在高温条件下进行退火处理，抑制伴随碳化而产生的缺陷的发生。这种方法虽然可以降低晶体合成过程中导致的碳化硅晶体产生缺陷的问题，但是没有在碳化硅生长过程中解决，碳包裹物大部分是在碳化硅生长过程中就会出现，而是延长了工艺步骤，试图利用退火工艺弥补前期的不足，但是由于晶格缺陷产生之后，无法简单的通过退火等步骤来降低其影响，且该申请将整个合成工艺变的更为复杂，产品质量更不可控。
发明内容
为了解决上述问题，本申请提出了一种碳化硅单晶生长装置，包括生长腔，所述生长腔用于放置原料，并提供原料受热升华的场所，所述生长腔分为放置原料的原料部和供原料升华结晶的气体流通区域；所述生长腔中设置若干导热容器，所述导热容器设在原料部，所述导热容器与生长腔的内壁隔离设置。
在导热容器中加入Si粉与SiC粉的混合物，将原料置于原料部，将导热容器置于原料中，在保护气气氛的作用下加热使得原料升华，导热容器中的混合物用来补充原料中的Si元素。
导热容器用于放置补充物质，补充物质至少含有硅元素和碳元素，碳与硅的摩尔比为0‐1:1，优选0‐0.5:1。在生长腔中设置导热容器，一方面是为了在导热容器中放置需要补充的物质，在本申请中，由于碳化硅单晶生长过程中Si/C比会失衡，在富碳的生长环境下，晶体生长的前沿 界面会有碳的富集并形成碳包裹体缺陷，所以本申请在导热容器中放置Si粉或Si粉与SiC粉的混合物，用来补充硅组分，进而调节Si/C比；另一方面，导热容器由于具有导热性，所以在生长腔中可以调节原料部的温度场分布，减少原料的碳化。Si元素补充装置中，可以是单质Si粉，也可以是单质Si粉与SIC粉料的混合物，但需保持单质Si粉与整个体系的SiC粉料的质量比。优选Si粉与SiC粉料的混合物，这样可以减少Si粉与补充装置内壁直接接触而过早发生反应。Si粉的重量根据质量比进行计算，SiC粉料的量以装满Si元素补充装置为宜。
优选地，导热容器包括容器本体和容器盖。容器盖的设置是为了补充物质的取放更方便。
优选地，在通孔内设有石墨层。
优选地，容器本体和/或容器盖上设置有若干通孔。通孔的设置是为了利于容器本体内Si粉与SiC粉受热升华后气相的传输，更方便原料中硅组分的补充。
优选地，导热容器为钽材料坩埚或镀钽石墨材料坩埚。由于Si粉在高温、高压下升华成气相，对石墨坩埚有侵蚀作用，若导热容器为钽材料坩埚或镀钽石墨材料坩埚，就很好的避免了对坩埚的侵蚀，在碳化硅单晶生长结束后可利用一定的方法取出，实现重复利用，降低成本。
优选地，导热容器为石墨坩埚，在石墨坩埚上设有石墨坩埚盖。导热容器为石墨坩埚，主要是利用了Si粉在高温、高压下升华成气相，对石墨坩埚有侵蚀作用，从而实现向原料中释放Si元素，并且随着长晶过程的进行而为原料持续补充Si组分。
优选地，在导热容器内设有若干侵蚀部，所述侵蚀部的壁厚小于石墨坩埚的平均壁厚，所述侵蚀部的壁厚小于石墨坩埚盖的平均厚度。在长晶过程中，随温度的上升，导热容器中的Si粉开始液化并开始与石墨坩埚壁开始发生反应，随着时间的延续，导热容器壁的最薄处首先被Si组分完全侵蚀，开始向原料中释放Si元素，并且随着长晶过程的进行而为原料持续补充Si组分。
优选地，侵蚀部形成的侵蚀空间的形状为圆锥或圆台，圆锥或圆台的底面远离导热容器的外壁设置。
优选地，侵蚀空间位于导热容器的底部。侵蚀空间位于导热容器底部时，Si粉受热时先侵蚀导热容器的底部，Si组分是从导热容器的底部向原料中释放Si元素。
优选地，导热容器设置在原料部的底部中间区域或靠近生长腔侧壁的区域。这样的设置是为了导热容器可以更好的起到调节原料区热场的作用。
可选地，所述导热容器为小坩埚，所述生长腔为外坩埚。
可选地，所述用于碳化硅单晶生长的装置，包括外坩埚，在外坩埚外设置保温加热装置，所述外坩埚分为放置原料的原料部和供原料升华结晶的气体流通区域；所述外坩埚中设置若干小坩埚，所述小坩埚设在原料部，所述小坩埚与外坩埚的内壁隔离设置；所述小坩埚包括容器本体和容器盖；所述小坩埚设置在原料部的底部中间区域或靠近外坩埚侧壁的区域。
本申请采用上述结构，能够带来如下有益效果：
1.本申请可以有效的调节在碳化硅单晶生长中生长腔室中的Si/C比例，从而减少单晶生长产生的碳包裹体缺陷；
2.本申请可以有效地调节原料区的温度场分布，减少原料的碳化；
3.本申请具有使用便利、结构简单、可靠，经济性强的特点；
4.本申请具有操作简单、安全性强、实用性强、适合推广使用的特点。
附图说明
此处所说明的附图用来提供对本申请的进一步理解，构成本申请的一部分，本申请的示意性实施例及其说明用于解释本申请，并不构成对本申请的不当限定。在附图中：
图1为一种碳化硅单晶生长装置结构示意图；
图2为导热容器的容器盖结构示意图；
图3为另一种导热容器结构示意图。
具体实施方式
为能清楚说明本方案的技术特点，下面通过具体实施方式，并结合其附图，对本申请进行详细阐述。
如图中所示，为了更清楚的阐释本申请的整体构思，下面结合说明书附图以示例的方式进行详细说明。
另外，在本申请的描述中，需要理解的是，术语“中心”、“上”、“下”、“前”、“后”、“左”、“右”、“竖直”、“水平”、“顶”、“底”、“内”、“外”、“轴向”、“径向”、“周向”等指示的方位或位置关系为基于附图所示的方位或位置关系，仅是为了便于描述本申请和简化描述，而不是指示或暗示所 指的装置或元件必须具有特定的方位、以特定的方位构造和操作，因此不能理解为对本申请的限制。
本说明书中的各个实施例均采用递进的方式描述，各个实施例之间相同相似的部分互相参见即可，每个实施例重点说明的都是与其他实施例的不同之处。
此外，术语“第一”、“第二”仅用于描述目的，而不能理解为指示或暗示相对重要性或者隐含指明所指示的技术特征的数量。由此，限定有“第一”、“第二”的特征可以明示或者隐含地包括一个或者更多个该特征。在本申请的描述中，“多个”的含义是两个或两个以上，除非另有明确具体的限定。
在本申请中，除非另有明确的规定和限定，术语“安装”、“相连”、“连接”、“固定”等术语应做广义理解，例如，可以是固定连接，也可以是可拆卸连接，或成一体；可以是机械连接，也可以是电连接，还可以是通信；可以是直接相连，也可以通过中间媒介间接相连，可以是两个元件内部的连通或两个元件的相互作用关系。对于本领域的普通技术人员而言，可以根据具体情况理解上述术语在本申请中的具体含义。
在本申请中，除非另有明确的规定和限定，第一特征在第二特征“上”或“下”可以是第一和第二特征直接接触，或第一和第二特征通过中间媒介间接接触。在本说明书的描述中，参考术语“一个实施例”、“一些实施例”、“示例”、“具体示例”、或“一些示例”等的描述意指结合该实施例或示例描述的具体特征、结构、材料或者特点包含于本申请的至少一个实施例或示例中。在本说明书中，对上述术语的示意性表述不必须针对的是相同 的实施例或示例。而且，描述的具体特征、结构、材料或者特点可以在任一个或多个实施例或示例中以合适的方式结合。
实施例1：碳化硅单晶生长装置：
如图1所示，本申请提供了一种碳化硅单晶生长装置，包括：生长腔1，生长腔1用于放置原料，并提供原料受热升华的场所，生长腔1分为放置原料的原料部11和供原料升华结晶的气体流通区域12；生长腔1为坩埚或其他可以实现碳化硅生长的容器，原料部11和气体流通区域12可以是在一个密闭空间的上下分部，例如：生长腔1为坩埚，原料部11为坩埚内腔的底部放置原料的区域，气体流通区域12为坩埚内上部没有原料的气相空间；原料部11和气体流通区域12也可以是分开独立的部件，是本领域技术人员可以实现的其他分布方式。
在生长腔1中设置若干导热容器111，导热容器111设在原料部11，导热容器111与生长腔1的内壁隔离设置，导热容器111设置在原料部11的底部中间区域或靠近生长腔1侧壁的区域。至于放置多少导热容器111比较合适，跟放置的原料量与生长腔1尺寸有关。
本实施例中的导热容器111包括容器本体和容器盖112。如图2所示，容器本体和/或容器盖112上设置有若干通孔113，导热容器111为钽材料坩埚或镀钽石墨材料坩埚，本实施例中导热容器111的材质不限于钽材料或镀钽石墨材料，只要是可以满足导热以及不被Si粉在高温下侵蚀的材料就可以。在通孔113上需要设置石墨密封以延缓Si粉散失的速度并控制释放时间。
如图3所示，本申请提供了另一种导热容器111，导热容器111为石 墨坩埚，本实施例中导热容器111也不限于是石墨材料，只要满足可以导热，在高温下可以被Si粉侵蚀就可以。在石墨坩埚上设有石墨坩埚盖114，石墨坩埚盖114紧密固定于石墨坩埚上。
在导热容器111内设有若干侵蚀部115，所述侵蚀部115的壁厚小于石墨坩埚的平均壁厚，所述侵蚀部115的壁厚小于石墨坩埚盖114的平均厚度。侵蚀部115形成的侵蚀空间的形状为圆锥或圆台，圆锥或圆台的底面远离导热容器111的外壁设置。侵蚀空间位于导热容器111的底部。导热容器111设置在原料部11的底部中间区域或靠近生长腔1侧壁的区域。本实施例中的导热容器111侵蚀部115的形状以及壁厚是可以根据需要调整的，根据需要补充的Si组分的量以及补充速率来确定侵蚀部115的形状以及壁厚等参数。
实施例2：碳化硅单晶的生长方法：
S1、在碳化硅单晶生长装置内装入碳化硅原料和籽晶，在碳化硅原料中埋入若干导热容器，导热容器中装有Si粉，将碳化硅单晶生长装置固定于热源上，通入保护气体；
S2、加热碳化硅单晶生长装置，温度升至第一温度，气体压力维持在第一压力；
S3、将碳化硅单晶生长装置内的压力逐步降低至第二压力，同时将炉温逐步提升至第二温度；
S4、生长结束后，在第一时间范围内将压力缓慢提升至第三压力，同时保持温度的稳定；
S5、最后将压力快速提升至一个大气压，同时将温度自然冷却至室 温，晶体生长结束。
作为一种实施方式，导热容器可以为小坩埚，生长腔可以为外坩埚。
关于小坩埚布置方案：
Si元素补充装置设置在原料高温区，SiC粉料较早出现碳化的位置，可根据原料的温度分布实施不同设置方案，但需保证同一高度设置点的均匀分布。布置方案如下表：
Figure PCTCN2018123717-appb-000001
具体的实施条件如下：
Figure PCTCN2018123717-appb-000002
Figure PCTCN2018123717-appb-000003
实施例3：表征
对包裹体浓度的测试方法为：选取生长出的晶体10块，晶体切片后在显微镜下观察其他包裹体情况，每块晶体统一抽取第10片和第20片，在50倍放大倍数下，统计的包裹体浓度。
厚度差为：选取生长出的晶体10块，其边缘的最大厚度与最小厚度之差的平均值。
微管数目为：选取生长出的晶体10块中出现大簇微管的数目。
Figure PCTCN2018123717-appb-000004
Figure PCTCN2018123717-appb-000005
根据对比例和样品1以及样品2的实验数据对比可知在碳化硅单晶生长装置中设置Si元素补充装置，碳包裹浓度明显下降，晶体边缘厚度差以及微管数目都明显降低，说明通过在碳化硅单晶生长装置中设置Si元素补充装置，Si元素补充装置中放置Si粉或Si粉与SiC粉的混合物，在碳化硅生长过程中补充Si，调节Si/C比，使得到的晶体质量明显提高；另外，采用可穿透的单晶生长装置的形式较于不可穿透的带有通孔的单晶生长装置的形式，由于在适宜条件下，可以控制Si元素补充装置漏出的时间以及Si元素补充装置被破坏的时间，因此能够达到更好的控制效果，提高质量；而带有通孔的单晶生长装置由于可以控制漏出时间，在某种程度上可以控制Si元素补充的时间，因此较于普通的碳化硅生长装置，可以得到质量更好的晶体。
本说明书中的各个实施例均采用递进的方式描述，各个实施例之间相同相似的部分互相参见即可，每个实施例重点说明的都是与其他实施例的不同之处。尤其，对于***实施例而言，由于其基本相似于方法实施例，所以描述的比较简单，相关之处参见方法实施例的部分说明即可。
以上所述仅为本申请的实施例而已，并不用于限制本申请。对于本领域技术人员来说，本申请可以有各种更改和变化。凡在本申请的精神和原理之内所作的任何修改、等同替换、改进等，均应包含在本申请的权利要求范围之内。

Claims (11)

  1. 一种碳化硅单晶生长装置，其特征在于，包括：
    生长腔，所述生长腔用于放置原料，并提供原料受热升华的场所，所述生长腔分为放置原料的原料部和供原料升华结晶的气体流通区域；
    所述生长腔中设置若干导热容器，所述导热容器设在原料部，所述导热容器与生长腔的内壁隔离设置。
  2. 根据权利要求1所述的一种碳化硅单晶生长装置，其特征在于：所述导热容器包括容器本体和容器盖。
  3. 根据权利要求2所述的一种碳化硅单晶生长装置，其特征在于：所述容器本体和/或容器盖上设置有若干通孔。
  4. 根据权利要求3所述的一种碳化硅单晶生长装置，其特征在于：所述在通孔内设有石墨层。
  5. 根据权利要求1‐4任一所述的一种碳化硅单晶生长装置，其特征在于：所述导热容器为钽材料坩埚或镀钽石墨材料坩埚。
  6. 根据权利要求1所述的一种碳化硅单晶生长装置，其特征在于：所述导热容器为石墨坩埚，在石墨坩埚上设有石墨坩埚盖。
  7. 根据权利要求6所述的一种碳化硅单晶生长装置，其特征在于：在导热容器内设有若干侵蚀部，所述侵蚀部的壁厚小于石墨坩埚的平均壁厚，所述侵蚀部的壁厚小于石墨坩埚盖的平均厚度。
  8. 根据权利要求7所述的一种碳化硅单晶生长装置，其特征在于：所述侵蚀部形成的侵蚀空间的形状为圆锥或圆台，圆锥或圆台的底面远离导热容器的外壁设置。
  9. 根据权利要求8所述的一种碳化硅单晶生长装置，其特征在于：所述侵蚀空间位于导热容器的底部。
  10. 根据权利要求1所述的一种碳化硅单晶生长装置，其特征在于：所述导热容器设置在原料部的底部中间区域或靠近生长腔侧壁的区域。
  11. 根据权利要求1所述的一种碳化硅单晶生长装置，其特征在于：所述导热容器为小坩埚，所述生长腔为外坩埚。
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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2022061386A1 (de) * 2020-09-28 2022-03-31 Ebner Industrieofenbau Gmbh Vorrichtung zur siliziumcarbideinkristall-herstellung
CN115491759A (zh) * 2022-11-16 2022-12-20 浙江晶越半导体有限公司 一种用于制备碳化硅单晶的附加粉源容器及坩埚装置

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20080115719A1 (en) * 2006-09-27 2008-05-22 Ii-Vi Incorporated Reduction of carbon inclusions in sublimation grown SiC single crystals
JP2010280546A (ja) * 2009-06-05 2010-12-16 Bridgestone Corp 炭化珪素単結晶の製造方法
CN106894091A (zh) * 2017-03-28 2017-06-27 山东大学 用于物理气相传输法生长碳化硅晶体的坩埚
CN107059130A (zh) * 2017-04-20 2017-08-18 山东大学 一种减少碳化硅单晶中包裹体的新型坩埚及利用坩埚生长单晶的方法
CN107385512A (zh) * 2017-06-30 2017-11-24 山东天岳先进材料科技有限公司 一种抑制碳化硅单晶中碳包裹体缺陷的生长方法

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20080115719A1 (en) * 2006-09-27 2008-05-22 Ii-Vi Incorporated Reduction of carbon inclusions in sublimation grown SiC single crystals
JP2010280546A (ja) * 2009-06-05 2010-12-16 Bridgestone Corp 炭化珪素単結晶の製造方法
CN106894091A (zh) * 2017-03-28 2017-06-27 山东大学 用于物理气相传输法生长碳化硅晶体的坩埚
CN107059130A (zh) * 2017-04-20 2017-08-18 山东大学 一种减少碳化硅单晶中包裹体的新型坩埚及利用坩埚生长单晶的方法
CN107385512A (zh) * 2017-06-30 2017-11-24 山东天岳先进材料科技有限公司 一种抑制碳化硅单晶中碳包裹体缺陷的生长方法

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2022061386A1 (de) * 2020-09-28 2022-03-31 Ebner Industrieofenbau Gmbh Vorrichtung zur siliziumcarbideinkristall-herstellung
TWI799980B (zh) * 2020-09-28 2023-04-21 奧地利商艾伯納工業爐公司 用於製備碳化矽單晶的裝置
CN115491759A (zh) * 2022-11-16 2022-12-20 浙江晶越半导体有限公司 一种用于制备碳化硅单晶的附加粉源容器及坩埚装置

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