SUBSURFACE MICROSCOPY OF BIASED METAL-OXIDE-SEMICONDUCTOR FIELD-EFFECT-TRANSISTOR STRUCTURES - PHOTOTHERMAL AND ELECTROREFLECTANCE IMAGES

In this work we used reflectance microscopy to investigate biased meta l-oxide-semiconductor field-effect-transistor (MOSFET) structures. A r esolution of micrometer is achieved by using visible laser light to pr obe the gate surface, and both electroreflectance and thermoreflectanc e components were found in the signal. Image contrast depends upon the bias configuration, and a total of six different types of images can be obtained. The high ability of the technique to detect subsurface de fects is also demonstrated. (C) 1998 Elsevier Science S.A. All rights reserved.