p型Ge单晶VGF生长位错抑制研究  

Research of Inhibition p Type Germanium Crystal Dislocation by Vertical Gradient Freeze Technique

作　　者：周春锋[1] 兰天平[1] 周传新[1] 

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》2016年第2期138-142,共5页Semiconductor Technology

摘　　要：垂直梯度凝固(VGF)法在单晶生长时温度梯度低,热应力小,是目前制备大尺寸、低缺陷晶体的首选方法。在不同的工艺条件下开展了p型VGF锗单晶生长实验研究。通过控制不同温区的温度和降温速率来减小生长温度梯度和晶体内部的应力。在保证VGF锗单晶成晶率的前提下,明显降低了锗单晶的位错密度和位错排的数量。研究发现,温度梯度在2~3℃·cm^(-1)内可保证单晶生长且使4英寸(1英寸=2.54 cm)锗单晶片平均位错密度降低到3 000 cm^(-2)以下。此外对VGF法生长锗单晶表面沟槽的形成原因进行了分析研究。The vertical gradient freeze （VGF） method can lower the temperature gradient and reduce the stress during crystal growth, which has become one of the main processes in the lager-size and low defects crystal growth. By the VGF method, the experimental studies on the growth of p type germa- nium single crystal under the different processing conditions were carried out. The temperature gradient and the thermal stress were obviously lowered by controlling the temperature and cooling rate at the different temperature area. With the high manufacture efficiency of the single crystal, the dislocation density and the number of dislocation array in germanium crystal were significantly reduced. The reasearch show that temperature gradient in the 2- 3 ℃ · cm^-1 , the dislocation density of 4 inch germanium wafer is de- creased by 3 000 cm-2. In addition, the formation of the surface groove of germanium single crystal with the VGF method is also discussed.

关 键 词：P型 锗单晶 垂直梯度凝固(VGF) 位错 位错排 

分 类 号：TN304.055[电子电信—物理电子学] TN304.11