LPCVD In-situ arsenic doped polysilicon for VLSI applications

A novel process for the growth of in-situ arsenic doped polysilicon has been developed in a conventional low pressure CVD reactor. The deposition parameters and the film properties have been investigated. The films have been applied to advanced bipolar transistors as emitter contact and arsenic diffusion source, and to CMOS DRAMs as capacitor contact and trench fill material. Thickness and resistivity uniformity, doping profiles within the poly and outdiffused into the single crystal and conformality of the films deposited in deep trenches are shown.