LEC法生长高质量6英寸InP单晶  

High Quality 6-inch InP Single Crystal Grown by LEC Method

作　　者：邵会民[1,2] 孙聂枫 张晓丹[1,2] 王书杰 刘惠生 孙同年 康永[1,2] Shao Huimin;Sun Niefeng;Zhang Xiaodan;Wang Shujie;Liu Huisheng;Sun Tongnian;Kang Yong(The 13th Research Institute,CETC,Shijiazhuang 050051,China;China Nanhu Academy of Electronics and Information Technology;Science and Technology on ASIC Laboratory,Shijiazhuang 050051,China)

机构地区：[1]中国电子科技集团公司第十三研究所,石家庄050051 [2]中国电子科技南湖研究院,浙江嘉兴314051 [3]专用集成电路重点实验室,石家庄050051

出　　处：《半导体技术》2020年第8期617-622,651,共7页Semiconductor Technology

基　　金：国家自然科学基金面上项目(51871202);国家自然科学青年基金资助项目(51401186)。

摘　　要：制备大直径单晶是降低器件成本的重要手段之一。对于制备大尺寸半绝缘InP单晶而言,由于其需要在高温高压环境下生长,随着热场尺寸的增大,炉体中气氛以及熔体中的对流增大,因而易产生孪晶和多晶。采用液封直拉(LEC)技术,通过多温区热场优化设计,调节各段加热器功率,降低了大尺寸热场温度梯度,提高了热场的对称性和稳定性,获得了平坦的固液界面,同时采用平缓放肩工艺抑制孪晶的形成。重复生长出约9.5 kg的6英寸(1英寸=2.54 cm)InP单晶,直径6英寸以上的单晶部分长度大于67 mm。测试结果表明,单晶片位错密度小于1×104 cm-2,电阻率大于107Ω·cm。从晶体生长和测试结果可以看出,合适的温度梯度可以使固液界面比较平坦,有效降低InP晶体的位错密度,电阻率片内均匀性为8.7%。The preparation of large-diameter single crystals is one of the important methods to reduce the cost of devices.For the preparation of large-size semi-insulating InP single crystals,due to the need to grow in a high temperature and high pressure environment,as the thermal field size increases,the atmosphere in the furnace and the convection in the melt increase,thus twin crystals and polycrystals are easily to be produced.By using the liquid encapsulation Czochralski(LEC)method,through the optimization design of the multi-zones thermal field and adjustment of the power of each section of the hea-ter,the temperature gradient of the large-scale thermal field was reduced,the symmetry and stability of the thermal field were improved,and the flat solid-liquid interface was obtained.Meanwhile the flat shoulder technique was used to inhibit the formation of twin crystals.The InP single crystals of 9.5 kg with a diameter of 6 inch(1 inch=2.54 cm)were repeatedly grown,and the length of single crystals over 6 inch in diameter was greater than 67 mm.The test results show that the dislocation density of the single crystal wafer is less than 1×104 cm-2,and the resistivity is greater than 107Ω·cm.The results of crystal growth and measurement show that the proper temperature gradient can make the solid-liquid interface flat,effectively reduce the dislocation density of the InP crystal,and have good in-wafer uniformity of resistivity of 8.7%.

关 键 词：INP单晶 液封直拉(LEC)法 温度梯度 位错密度 平缓放肩工艺 

分 类 号：TN304.053[电子电信—物理电子学] TN3W.23