Hydrogen reactions with electron irradiation damage in silicon

We have irradiated n-type CZ silicon with 2 MeV electrons at room temperatu re, and atomic hydrogen has been introduced either before or after irradiat ion from the surface by wet etching. Quantitative comparisons of vacancy-re lated defects before and after the hydrogen reactions have been made using high-resolution (Laplace) DLTS. A deep level appears after hydrogenation at E-C - 0.311 eV, with two components detected by Laplace DLTS. This has pre viously been reported to be due to either VOH or VOH2, and is accompanied b y a decrease in the intensity of the A centre (VO). The Laplace DLTS shows that the A centre emission rate is modified by the hydrogen, and a slower e mission rate from the A centre is observed in the presence of hydrogen. Dep th profiling shows that this modification occurs in the expected spatial lo cation of the introduced hydrogen. (C) 1999 Elsevier Science B.V. All right s reserved.