Formation of Shallow Boron P⁺ Junctions Using Sb Amorphization

Abstract

Shallow P⁺ junctions have been fabricated using reverse-type dopant preamorphization by Sb. The junctions ~100 nm in depth have leakage current below 10 nA/cm², sheet resistance less than 200 Ω☐ and ideality factor in the range 1.01-1.03. This type of amorphization scheme provides electrical activation of B at low temperature, which is very promising for low temperature processing applications. The importance of process optimization was demonstrated. The electrical results were correlated with residual defect structure observed by cross-sectional TEM.