The effects of bulk microdefects and metallic impurities on leakage currents at p–n junctions have been evaluated quantitatively by relating leakage currents with bulk defects and metallic impurities, and the results are reported. Bulk defects and metallic impurities, which were introduced by appropriate thermal treatment and intentional contamination by spin-coating metal ion solutions onto the silicon surfaces, were shown to induce heavy leakage currents at p–n junctions, which had been manufactured by boron implantation and phosphorus diffusion. We found the bulk microdefects to be critical in causing leakage currents to flow and propose that their measurements be used as a means for the determination of the bulk defect densities. Die failure rates were also used for the evaluation of the effects of metallic impurities such as Cu, Ni, and Fe on the leakage currents.

Adverse influences of organic contaminants on electronic devices have been studied and the results are reported. Contamination of silicon wafers by organic compounds during their manufacturing processes has been clearly demonstrated by a few surface analytical techniques. Silicon wafers were intentionally contaminated by one of the major contaminants, bis(2-ethylhexyl) phthalate; its incorporation into the silicon oxide layer during thermal oxidation of silicon and its influences on device performances have been evaluated in detail by monitoring the breakdown voltages. During thermal oxidation of the contaminated silicon surface, the atomized carbon species produced from pyrolysis of organic contaminants help grow the oxide thicker, expand the silicon oxide lattice, and degrade the silicon oxide, which was shown by transmission electron microscopy and secondary ion mass spectroscopy, and finally exert adverse influences on the device performance.