Hydrogen reactions with electron irradiation damage in silicon

We have irradiated n-type CZ silicon with 2 MeV electrons at room temperature, and atomic hydrogen has been introduced either before or after irradiation from the surface by wet etching. Quantitative comparisons of vacancy-related 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 previously been reported to be due to either VOH or VOH(2), and is accompanied by 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 emission rate from the A centre is observed in the presence of hydrogen. Depth profiling shows that this modification occurs in the expected spatial location of the introduced hydrogen. (C) 1999 Elsevier Science B.V. All rights reserved.