Polysilicon capacitor failure during rapid thermal processing

Rapid thermal-processing-induced polysilicon capacitor failure is investigated. Polysilicon-SiO2-Si capacitors fail at the perimeter upon heating to temperatures in excess of 1050°C for a few seconds in vacuum or argon. Shorting occurs when the silicon grains deform due to surface energy-driven diffusion and extend over etch-damaged oxide surrounding the capacitor. The presence of oxygen or nitrogen during, or regrowth of the damaged oxide prior to, rapid thermal processing substantially reduces the failure rate.