半导体光电, 2014, 35 (4): 625, 网络出版: 2014-09-01
无掩模Si圆柱纳米图形衬底上GaAs的异变外延生长
Heteroepitaxial Growth of GaAs on Maskless Roundpillar Nanopatterned Si Substrate
摘要
采用金属有机化学气相沉积方法在无掩模的直径为400nm的圆柱Si(100)图形衬底上外延生长了GaAs薄膜。图形衬底采用纳米压印技术及反应离子刻蚀技术制作而成。运用两步法生长工艺在此图形衬底上制备了厚度为1.8μm的GaAs外延层。GaAs的晶体质量通过腐蚀坑密度和透射电镜表征。图形衬底上的 GaAs外延层表面腐蚀坑密度约1×107cm-2, 比平面衬底上降低了两个数量级。透射电镜观测显示大部分产生于GaAs/Si异质界面的穿透位错被阻挡在圆柱顶部附近。
Abstract
GaAs films were grown by metal organic chemical vapor deposition (MOCVD) on 400nm maskless roundpillar patterned Si (100) substrate. The patterned substrate was fabricated by combining nanoimprint lithography with reactive iron etching. 1.8μmthick GaAs epilayer was obtained on the patterned substrate using twostep method. The quality of GaAs was evaluated using etching pit density and transmission electron microscopy. The etching pit density of GaAs grown on patterned Si substrate at ~1×107cm-2 was two orders of magnitude lower compared with that grown on planar Si substrate. TEM observations reveal that most of the threading dislocations originated from the GaAs/Si interface were trapped near the top of the roundpillars.
李玉斌, 王俊, 王琦, 邓灿, 王一帆, 任晓敏. 无掩模Si圆柱纳米图形衬底上GaAs的异变外延生长[J]. 半导体光电, 2014, 35(4): 625. LI Yubin, WANG Jun, WANG Qi, DENG Can, WANG Yifan, REN Xiaomin. Heteroepitaxial Growth of GaAs on Maskless Roundpillar Nanopatterned Si Substrate[J]. Semiconductor Optoelectronics, 2014, 35(4): 625.