高纯度α-SiC粉料的合成  

Synthesis of High Purity α-SiC Powder

作　　者：张皓[1] 王英民 陈建丽[1] 孟大磊[1] Zhang Hao;Wang Yingmin;Chen Jianli;Meng Dalei(The 46^(th)Research Institute,CETC,Tianjin 300220,China;Shanxi Semicore Crystal Co.,Ltd.,Taiyuan 030024,China)

机构地区：[1]中国电子科技集团公司第四十六研究所,天津300220 [2]山西烁科晶体有限公司,太原030024

出　　处：《半导体技术》2021年第10期779-782,807,共5页Semiconductor Technology

摘　　要：为获得高纯半绝缘(HPSI)SiC生长用粉料,采用自蔓延高温合成(SHS)法获得了高纯度α-SiC粉料。在合成小粒径β-SiC粉料基础上,对粉料进行物理破碎,通过二次合成,经高温相转变和再结晶过程得到大粒径α-SiC粉料。利用X射线衍射(XRD)、辉光放电质谱(GDMS)、二次离子质谱(SIMS)、扫描电子显微镜(SEM)和激光粒度仪等测试手段对合成的粉料进行了表征和分析,并对使用该方法合成的SiC粉料进行了单晶生长验证,通过SIMS和非接触式电阻率测试仪等对SiC单晶的杂质浓度、电阻率等参数进行了测试。结果表明,增加破碎工艺环节后合成的α-SiC粉料N杂质浓度小于1.0×10^(16) cm^(-3),但粒径更大(平均值为1 853μm,中位径为1 851μm)、游离C质量分数更低(<0.01%)。采用高纯度α-SiC粉料减少了晶体内包裹物,有助于提高SiC晶体质量。High purity α-SiC powder for high purity semi-insulating(HPSI) SiC growth was prepared by using self-propagating high temperature synthesis(SHS) method.On the basis of synthesizing small particle size β-SiC powder, the powder was physically crushed, and the large particle size α-SiC powder was obtained through secondary synthesis, high temperature phase transformation and recrystallization.The synthesized powders were characterized and analyzed by X-ray diffraction(XRD), glow discharge mass spectrometry(GDMS), secondary ion mass spectroscopy(SIMS), scanning electron microscopy(SEM) and laser particle size analyzer.The single crystal growth of SiC powder synthesized by this method was verified.The impurity concentration and resistivity of SiC single crystal were measured by SIMS and non-contact resistivity tester.The results show that after adding the crushing process, the nitrogen impurity concentration of the synthesized α-SiC powder is less than 1.0×10^(16) cm^(-3), and the powder has larger particle size(average value of 1 853 μm, the median diameter of 1 851 μm) and the mass fraction of free carbon is lower than 0.01%.Moreover, the inclusions in the crystals are reduced and the quality of SiC single crystal has been improved by utilizing the high purity α-SiC powder.

关 键 词：高纯半绝缘(HPSI) 游离C α-SiC 自蔓延高温合成(SHS)法 高纯度 

分 类 号：TN304.24[电子电信—物理电子学]