PRODUCTION PROCESS OF SIMOX WAFER

摘要

PROBLEM TO BE SOLVED: To obtain an MLD-SIMOX wafer having a thin BOX layer in which dielectric breakdown voltage characteristics can be enhanced by reducing surface roughness of an SOI layer and interface roughness of the BOX layer and the SOI layer. SOLUTION: The production process of an SIMOX wafer comprises a step for forming a first ion implantation layer 12 in a silicon wafer 11, a step for forming a second ion implantation layer 13 under amorphous state, and a high temperature annealing step for making the first and second ion implantation layer a BOX layer 14 by holding the wafer in an oxygen containing atmosphere at a temperature between 1,300°C and the melting point of silicon. The dose of the first ion implantation layer is 1.25 to 1.5×1017atoms/cm2, and the dose of the second ion implantation layer is 1.0×1014to 1×1016atoms/cm2. Furthermore, a step for preheating the wafer at a temperature between 50-200°C is included before the step for forming the second ion implantation layer, and the second ion implantation layer is formed under a state where the wafer is heated continuously at the preliminary heating temperature. COPYRIGHT: (C)2007,JPO&INPIT