多晶硅、单晶硅同步外延研究

介绍了多晶硅、单晶硅的同步外延.采用两步外延工艺,研究了硅烷流量、外延时间以及外延温度对外延质量参数α的影响.硅烷流量大、初始诱生时间短,则单晶硅条宽,多晶硅横向蔓延弱,但外延层质量可能较差.较优的条件是:硅烷诱生生长流量为13.1～17.5sccm,正常生长流量为7.0～7.88sccm,初始诱生时间为30～50s.温度影响较复杂,当温度低于980℃时,单晶硅条宽随温度增加而增加,在980℃附近达到最大,随后随温度增加单晶条宽降低.

Study on Synchro-Epitaxy of Poly- and Single Crystal Silicon

Synchro-epitaxy is introduced and a "two periods epitaxy" process is proposed.The influence of the flows of SiH4 N1,N2,deposition time t1,t2,and epitaxial temperature T on epilayer quality (embodied by α) is reported.The shorter initial inducing time t1 and larger flows of SiH4 are,the wider single crystal strips are.But the quality of epilayer may be poor.The optimum conditions are:N1=13.1～17.5sccm,N2=7.0～7.88sccm,and t1=30～50s.The influence of temperature is complex:when T is lower than 980℃,single crystal strips increase with T ;when T is higher than 980℃,single crystal strips decrease with T.It reaches maximum near 980℃.