Influence of RTP flash anneal ramp rates on lithography overlay performance on 300 mm integrated wafers

The influence of RTP with high ramp rates on lithography overlay distortion was investigated in this work using sub-quarter-micron technology on 300 mm wafers. The concentrations of interstitial oxygen was varied, as well as ramp rates and lamp correction tables used to optimise the across-wafer temperature uniformity. The influence of these parameters on the rapid thermal anneal (RTA) performance was studied. Wafer geometry and lithography overlay measurements where used to determine the impact of the material and RTA process parameters to lithography pattern shifts.