Ion-implanted polysilicon diffusion sources

SIMS and TEM techniques are employed to study redistribution of boron and arsenic implanted into polysilicon deposited on crystalline silicon substrates. Various implant conditions and thermal treatments are included. The interface between the poly and single crystal Si strongly influences the dopant distribution. Morphology changes are also affected by the interface and play an important roll in the dopant redistribution. Interactive effects between boron and arsenic are observed in polysilicon which are attributed to the electric field generated by the arsenic gradient. The quality of the interface is associated with the quantity of oxygen, flourine, and carbon found in that region. © 1983.