This work is believed to be the first report of localized elevated oxygen concentration (or pileup), which occurs with thermal anneals of strained, boron-doped SiGeC layers. The thermally activated oxygen updiffusion is directly correlated to concentrations of germanium, carbon, and boron. A strong dependency on the prebake temperature was also found. Secondary ion mass spectrometry measurements were made to verify O, C, B, and Ge concentrations in SiGeC layers following low temperature growth by low pressure chemical vapor deposition and also following thermal anneal. (c) 2005 The Electrochemical Society.