摘要
台面结构SiGe/Si异质结晶体管制作过程中,发射区台面形成尤为关键。由于干法刻蚀速率难以精确控制,且易损伤SiGe外基区表面,SiGe自中止湿法腐蚀成为台面结构SiGe/Si异质结晶体管制作过程中的优选工艺。分析了SiGe自中止腐蚀的反应机理,对腐蚀条件包括掩蔽膜的选取,温度、超声等因素对腐蚀速率及均匀性的影响进行摸索,取得了较好结果,最终采用该技术完成了SiGe/Si npn型异质结晶体管的制作,测得其电流增益β>80,对采用台面结构制造SiGe/Si HBT具有一定参考价值。
Emitter mesa formation is a key technology for mesa SiGe/Si HBT fabrication.As the etching velocity of the dry etching is difficult to control and it is easy to damage the external base surface,the self-ceasing wet etching becomes an optimal technique for fabricating emitter mesa SiGe/Si HBTs.The chemical mechanism of the self-ceasing etching technology was analyzed.The etching conditions including the choice of the mask,the effects of temperature and ultrasonic power on etching velocity and uniformity,were obtained.Finally,the SiGe HBT with the current gain β80 was fabricated by this technology.It is valuable for fabricating SiGe/Si HBTs.
出处
《半导体技术》
CAS
CSCD
北大核心
2011年第9期689-692,共4页
Semiconductor Technology
基金
邯郸市科学技术研究与发展计划项目(1155103119-4)
