High-Quality Low-Dose SIMOX Wafers

摘要

This paper reviews the structure and electrical properties of high-quality Internal Thermal OXidation (ITOX) -processed low-dose Separation by IMplanted OXygen (SIMOX) wafers. The ITOX SIMOX process consists of three steps: low-dose oxygen implantation, high-temperature annealing, and high-temperature oxidation. The low dose makes possible a high-throughput production of SIMOX wafers. The high-temperature annealing provides a continuous buried oxide layer and reduces the dislocation density in the top silicon layer. The subsequent high-temperature oxidation thickens the buried oxide layer without any additional oxygen implantation, thus improving its electrical properties. The ITOX mechanism is also described. It is concluded that the ITOX SIMOX wafers are very useful for fabricating ULSIs.