Characteristic of Junction Leakage Current with Bulk Micro Defect Density in p-n+ Junctions

Abstract

We investigated the correlation between the junction leakagecurrent and bulk micro-defect (BMD) density for p-n+ junctions fabricated on Czochralski (CZ) Si wafers. In order to measure BMD, the wafers were annealed at 800oC for 4hr, followed by 1000oC for 8, 16, and 24 hr in a N2 ambient. After that, they were polished by 15 μm to remove the denuded zone (DZ) to disclose the BMD for detection using p-n+ junctions. We confirm the junction depth and dopant concentration of the p-n+ junctions by using secondary ion mass spectrometry (SIMS). After the electrical measurements we confirmed that the junction leakage current increases with increasing BMD density. The correlation factor between the junction leakage current and BMD density was about 99%.