LOCATION OF DEUTERIUM ON THE SILICON (100) MONOHYDRIDE SURFACE DETERMINED BY TRANSMISSION-ION CHANNELING

The location of deuterium (D) in the monohydride configuration on the silicon (100) surface is established using transmission-ion channeling. A 2-MeV [sup 4]He[sup +] ion beam was used to elastically recoil D from the beam-exit surface of a thin silicon crystal. The yield of recoiled D was measured versus angle about the [l angle]100[r angle], [l angle]110[r angle], and [l angle]111[r angle] axes. The location of the surface D relative to the silicon lattice was determined by comparing the measured yields with computer-channeling simulations. The observed location is consistent with a Si-D bond length of 1.6[plus minus]0.2 A along the silicon tetrahedral bond direction in agreement with recent [ital ab] [ital initio] theoretical calculations.