A method for fabricating semiconductor devices, e.g., strained silicon MOS device, includes providing a semiconductor substrate (e.g., silicon wafer) having a surface region, which has one or more contaminants and an overlying oxide layer. The one or more contaminants is at least a carbon species. The method also includes processing the surface region using at least a wet process to selectively remove the oxide layer and expose the surface region. The method further includes subjecting the surface region to a laser treatment process for a time period of less than 1 second to increase a temperature of the surface region to greater than 1000 degrees Celsius to remove the one or more contaminants provided on the surface region. The method also includes removing the laser treatment process to cause a reduction in temperature to about 300 to about 600 degrees Celsius in a time period of less than 1 second.