Deep Levels in W-Doped Czochralski Silicon

摘要

The deep levels introduced by W diffusion at 950 degrees C in p- and n-type Czochralski silicon have been studied by Deep-Level Transient Spectroscopy (DLTS). It is shown that in p-type Si, two prominent hole traps are present, one around mid-gap, showing a steeply decaying concentration profile within 1 mu m from the surface and a second center with activation energy of 0.409 eV above the valence band, exhibiting a rather flat profile beyond 0.4 mu m from the surface. In n-type Si, a small peak has been consistently found, which most likely corresponds with the 0.22 eV W-related electron trap previously reported in the literature. (C) 2015 The Electrochemical Society. All rights reserved.