J. Phys. IV France 125 (2005) 557-559
Infrared photocarrier radiometry with dc sub-bandgap optical bias: Sensitivity enhancement in the detection of deep subsurface electronic defects in Si wafersJ. Batista1, 2, A. Mandelis1, D. Shaughnessy1 and B. Li1
1 Center for Advanced Diffusion-Wave Technologies (CADIFT), Department of Mechanical and Industrial Engineering, University of Toronto, Toronto ON, M5S 3G8, Canada
2 Departamento de Física, Universidade Federal do Maranhão, São Luís, MA, 65085-580, Brazil
The physics of the contrast mechanism for the pure electronic nature of the infrared photocarrier radiometry (PCR) signal with a secondary dc IR optical bias is analyzed. The PCR technique is used for imaging electronic defect in a p-type Si wafer. The results show contrast over 5000% between signals generated from direct and the cross-modulated IR photon emissions. This new semiconductor diagnostic tool has proven to be extremely sensitive for characterization of physical properties that promote changes on carrier distribution through enhanced recombination across the bandgap and/or defect states within the bandgap.
© EDP Sciences 2005