OPTIMIZATION OF THE AMORPHOUS LAYER THICKNESS AND THE JUNCTION DEPTH IN THE PREAMORPHIZATION METHOD FOR SHALLOW-JUNCTION FORMATION

A 0.1- µm-deep p+/n junction was formed by the Si+preamorphization method. The thickness of the preamorphized layer and the junction depth were optimized systematically. It was found that the junction must be formed at a depth 70–90 nm greater than that of the amorphous/crystal (a/c) interface to reduce leakage current density J1to less than 1×10-8A/cm2. Furthermore it was confirmed that the preamorphized layer thickness influences the dependence of J1on the distance between the junction and a/c interface and that a thinner preamorphized layer forms a thinner or lower-defect-density residual defect layer. © 1990 IOP Publishing Ltd.