Abstract: A polysilicon diffusion doping method which employs a deposited dopant-rich oxide layer with a highly uniform distribution of dopant atoms and thickness. Polysilicon layers 1,500 angstroms thick have been doped, achieving average resistance values of 60 ohms and non-uniformity values of 5 percent. Resistance values were measured using the four-point probe method with probe spacings of 0.10 cm. After a polysilicon layer has been formed upon a surface of a silicon wafer, a dopant-rich oxide layer is deposited upon the polysilicon layer at reduced pressure. The dopant-rich oxide layer is deposited, and serves as a source of dopant atoms during the subsequent diffusion process. The dopant-rich oxide layer is a phosphosilicate glass (PSG) including phosphorus pentoxide (P.sub.2 O.sub.5) and phosphorus trioxide (P.sub.2 O.sub.3) and deposited using a PECVD technique.