Diffusion of boron into polycrystalline silicon from a single crystal source

Abstract

Boron was outdiffused at 900 °C from single crystal silicon into undoped chemical vapor deposited polycrystalline silicon. Boron concentration profiles measured by secondary ion mass spectrometry showed preferential segregation into the polysilicon with a segregation coefficient of 0.7. Pileup of boron at grain boundaries due to migration of boron ions in the interface field during the diffusion process can account for some of the observed segregation.