The detection of contaminants in manufacturing is essential for certain processes, and early contamination detection and tracing is beneficial for lowering the ultimate material cost of a product. In-situ wafer analysis is being used to examine metallic contamination in SIMOX silicon-on-insulator substrates during the early implantation stage of their fabrication.Used for advanced CMOS circuitry, the product is presently examined by total x-ray fluorescence (TXRF) as a part of the final quality control program. Early detection of any metallics in the active silicon layer would greatly improve chances for impurity source tracking and ultimate cost reduction. Researchers are designing and fabricating an in-situ, non-destructive impurity detection capability at the ion implantation station of SIMOX fabrication. Several design advantages which enhance detection sensitivity and ease of implementation are incorporated.Commercial Applications:The nation may expect to benefit from the development of an in-situ, non-destructive wafer contamination detection system. Such early stage detection may be used as an advanced quality control tool which will enhance product development and material for the silicon industry.
