EVALUATION OF AUTOMATED SPECTROSCOPIC ELLIPSOMETRY FOR IN-LINE PROCESS-CONTROL - ESPRIT SEMICONDUCTOR EQUIPMENT ASSESSMENT (SEA) PROJECT IMPROVE

The performance of an automatic spectroscopic ellipsometer, the SOPRA Multi-layer Monitor (MLM) has been evaluated over a 1-year period on r epresentative CMOS/Bipolar wafer structures supplied by IC manufacture rs. Precision, stability, throughput, and accuracy where possible, hav e been assessed for ONO, OPO, oxide, Si/SiGe and PECVD oxide/metal waf ers. Examples are given to illustrate the ability of the MLM to discri minate variations due to intrinsic and deliberately-induced process ch anges, as well as cross-wafer uniformity. Crown Copyright (C) 1998 Pub lished by Elsevier Science S.A.