Novel approach to defect etching in thin film SOI. Part 2
A new etch process including three sequential etch steps was developed to measure low defect densities in thin SOI silicon films. It allows for a fast, simple and cost effective measurement of defect densities in a range of about (10E3-10E9) x 1/cmü. Main advantages of this approach compared to earliers are independence from defect density and improved simplicity in addition with a better image contrast. Dependences of defect densities on the implanted oxygen dose and the implantation energy have been studied for SIMOX wafers. The experiment shows an increase of defect density with the dose and a decrease of defect density with the implantation energy. A comparison with TEM results shows a good agreement.