Processing Simox Wafer Below the Critical Temperature

Abstract

AbstractThe creation of SIMOX material by multiple step substoichiometry oxygen ion implantation of silicon wafers followed by high temperature annealing has already been demonstrated by different groups [1-4] This paper reports on the formation of SIMOX wafers at temperatures well below the critical temperature (500-550°C) specified for oxygen implantation of the SIMOX process. A multiple step procedure has been devised, each step consisting of oxygen ion implantation at doses of 2.5 and 3 x 1017 O+/cm2 followed by solid phase epitaxy at a temperature of 950°C for two hours. Non-destructive optical analysis and XTEM investigation of the wafers indicates the formation of a continuous buried oxide with good quality single crystal silicon on the surface after accumulated dose of 1.1x1018 O+/cm2 following high temperature annealing at 1300°C for six hours.The processing of SIMOX material at a lower temperature will enable the utilization of a wide variety of ion implanters, will simplify the design of the end station of the new generation high current ion implanters, and will have an impact on the availability and economics of SIMOX wafers.