Application of
IVS Overlay Measurement to Wafer Deformation Characterization Study
Ying Liu and Iain black
ANADIGICS INC.,
E-mail: yliu@anadigics.com; jblack@anadigics.com
Tel: (908) 668-5000 x6335m x6139
Keywords: IC gallium-arsenide process, Overlay measurement, GaAs wafer thermal distortion, and GaAs wafer deformation
Abstract
This work revealed on of the applications of overlay error measurement on investigation of GaAs wafer distortion during the normal high-temperature thermal process (above 800oC), using IVS overlay system. The results showed good correlation between the IVS overlay measurement and the temperature variation maps of the wafer obtained from temperature graduation experiments and electrical tests. The overlay error increased with increasing temperature.