高电阻率均匀性4英寸半绝缘GaAs单晶生长技术  

Growth Technology of 4-inch SI-GaAs Single Crystal with High Resistivity Uniformity

作　　者：兰天平[1] 周春锋[1] 边义午 宋禹 马麟丰 Lan Tianping;Zhou Chunfeng;Bian Yiwu;Song Yu;Ma Linfeng(The 46th Research Institute,CETC,Tianjin 300220,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

出　　处：《半导体技术》2020年第4期287-292,303,共7页Semiconductor Technology

摘　　要：4英寸(1英寸=2.54 cm)半绝缘GaAs单晶材料是目前制备微波毫米波单片集成电路等的主流材料,随着5G技术应用的普及,该材料的应用前景将更加广阔。但是由于采用常规垂直梯度凝固(VGF)法晶体生长工艺所得的单晶尾部径向电阻率均匀性较差,严重影响了相关器件性能的一致性。对采用VGF和(VGF+垂直布里奇曼(VB))两种晶体生长工艺所得的半绝缘GaAs单晶头尾径向电阻率不均匀性测试进行分析,优化了(VGF+VB)晶体生长相关工艺条件,并确定了VB晶体生长部分比较合理的起始位置及生长速度。在保证晶锭头尾电阻率均达到10~8Ω·cm以上的情况下,有效地降低了晶体尾部径向电阻率不均匀性,使其由原来的大于20%降低到小于10%,提高了晶体质量。通过该工艺还可有效排杂到晶体尾部,增加高电阻率单晶有效长度。The 4-inch(1 inch =2.54 cm)SI-GaAs single crystal material is the main material of producing microwave millimeter wave monolithic integrated circuits. With the popularization of 5 G technology, the application prospect test of SI-GaAs will be more broad. However, with the situation of poor radial resistivity uniformity of crystal tail grown by the routine vertical gradient freeze(VGF)method, the performance consistency of related devices was deeply affected. The radial resistivity uniformities test of SI-GaAs single crystal at the tail and head grown by VGF and(VGF+vertical Bridgman(VB)) methods were analyzed. The process conditions of(VGF+VB) crystal growth were optimized. The reaso-nable starting position and the growth speed of VB crystal were determined. The radial resistivity inhomogeneity of crystal tail was effectively reduced from more than 20% to less than 10%, under the condition that the resistivity of ingot head and tail reached more than 10~8 Ω·cm, and the crystal quality was greatly improved. Through this process, the impurity can be effectively discharged to the crystal tail and effective length of high resistivity single crystal can be increased.

关 键 词：GAAS 垂直梯度凝固(VGF) 垂直布里奇曼(VB) 晶体生长 电阻率 均匀性 

分 类 号：TN304.23[电子电信—物理电子学]