IMAGING OF DEEP DEFECTS USING TRANSMISSION ION CHANNELING

Stacking faults close to the back surface of a thinned silicon crystal have been imaged through 50 mu m of overlying material using transmis sion ion channeling with 3 MeV protons. These faults were deeper than those normally detectable using ion backscattering with a similar beam . Images were produced by mapping the mean energy loss of 3 MeV proton s transmitted through the crystal with the incident beam aligned with a planar channeling direction. Channeling in {111} planes is most effe ctive at revealing deep faults and imaging of such faults required a d etector with a restricted acceptance angle to be used.