GROWTH OF VERY-LOW TEMPERATURE POLYSILICON FILM BY REMOTE PLASMA-ENHANCED CHEMICAL-VAPOR-DEPOSITION

Silicon thin films have been prepared on SiO2 substrates by remote pla sma-enhanced chemical-vapor deposition using H-2/SiH4/Ar gases. The fi lm properties were found to critically depend on the variations of dep osition parameters, which include the SiH4 flow rate with a fixed H-2 flow rate, Ar flow rate, and radio frequency (rf) power. The substrate temperature was fixed at 280+/-5 degrees C. The best quality polysili con film was obtained when the rf(power)/Al ratio was set near 0.5+/-0 .05. In addition, the electrical mobility was observed to increase wit h the increasing SiH4 flow rate. The effects of the deposition paramet ers variation were discussed to properly account for the observed prop erties of the thin films studied. (C) 1997 American Vacuum Society.