Growth of Oxygen Precipitates in Low-Dose Low-Energy Simox

Abstract

Silicon-on-insulator (SOI) is becoming a key technology for low power electronics due to substantially reduced power consumption of electronic components, and a capability of compact circuit design which are not readily achievable in bulk silicon technology [1]. Separation by IMplantation of OXygen (SIMOX) is the most promising technology for fabricating SOI material. The basic SIMOX process consists of implantation of oxygen into the single crystalline silicon wafer and the subsequent high temperature annealing. Oxygen implantation at low doses does not form a continuous buried oxide (BOX) layer but leads to an inhomogeneous distribution of the oxygen precipitates during implantation process. The formation and growth of oxygen precipitates in low-dose SIMOX depend strongly on the implantation conditions such as oxygen dose, implantation temperature, annealing temperature and ramping rate [2,3]. During the subsequent annealing, Ostwald ripening of the precipitates takes place and the larger precipitates grow at the expanse of small ones until they coalesce to the buried oxide layer.