SELECTED APPLICATIONS OF PHOTOTHERMAL AND PHOTOLUMINESCENCE HETERODYNE TECHNIQUES FOR PROCESS-CONTROL IN SILICON-WAFER MANUFACTURING

Two noncontact laser-based heterodyne techniques, photothermal heterod yne (PTH) and photoluminescence heterodyne (PLH), are introduced and a pplied to processing and quality control in silicon wafer manufacturin g, The crystallographic characteristics of process-induced defects in silicon wafers are suitable for the application of PTH and PLH techniq ues, which are demonstrated on selected examples from different steps of silicon wafer production, Both PLH and PTH techniques meet the dema nd for nondestructive and on-line-suitable measurement in the semicond uctor industry. (C) 1997 Society of Photo-Optical Instrumentation Engi neers.