Application of rapid thermal oxidation to the development of high dielectric strength polyoxides

Electrical and morphological characteristics of thin oxides (∼200Å), grown by either Rapid Thermal Oxidation (RTO) or conventional furnace, on amorphous, in-situ phosphorus doped silicon films, have been studied. The results are compared to those obtained from oxidizing polysilicon films doped with phosphorus at 950°C from a PBr3source. The polyoxides grown by RTO on amorphous, in-situ doped silicon exhibit high breakdown fields (∼9.0 MV/cm) and low leakage current. Oxidation of the same films in a conventional furnace produces polyoxides with lower (∼6.0 MV/cm) breakdown fields. The breakdown fields of oxides grown on PBr3doped films are low (less than 5.5 MV/cm and strongly dependent on phosphorus concentration. RTO and conventional furnace polyoxides grown on PBr3doped polysilicon exhibit similar characteristics.