The suppression of short channel effect in strained-Si surface channel PMOSFET with carbon incorporation on relaxed SiGe buffers is demonstrated. The lateral diffusion of boron from source/drain into the channels is retarded by a reduction of interstitial formation due to carbon incorporation in the strained-Si layer. It is necessary to avoid the high temperature (> 900 degrees C) process for SiC precipitations as trap centers which are observed by atomic force microscope and X-ray diffraction. An incorporated carbon in the source/drain is not only being stressor but also improves short channel effect for extremely shallow junctions, and makes it possible to have high speed devices. (C) 2008 Elsevier B. V. All rights reserved.