Defect control in formation of dielectrically isolated semiconductor device regions

摘要

Oxygen induced lattice slip defects are reduced in device layer 26 of silicon-on-insulator structure 12, 16, 26. At the bottom of trenches 22 notches 28 are etched into the dielectric layer 16. A thermal oxide process provides protrusions 30 of oxide into the substrate. The protrusions 30 direct defects into the support layer 12.