Improving a doping profile during gas phase doping comprises preparing a semiconductor substrate, introducing silicon nitride and/or decomposition products of silicon nitride

摘要

Improving a doping profile during gas phase doping comprises preparing a semiconductor substrate; introducing silicon nitride and/or decomposition products of silicon nitride deposition in a process chamber; and gas phase doping in the chamber. Preferred Features: Ammonium chloride crystals are introduced into the process chamber together with small amounts of HCl and/or NH3. Gas phase doping is carried out in a pressure region of 13.33 Pa to 133.3 kPa and in a temperature region of 800-1100 deg C. Arsenic, phosphorus or boron gas doping is carried out. A trench is formed in the substrate and an insulating collar in an upper region of the trench.