Apparatus and method for patterned sequential lateral solidification of a
substrate surface, avoiding the need for demagnification to avoid
mask damage from
fluence sufficient to overcome the threshold for sequential lateral solidification, while using the high
throughput of a common stage presenting both 1:1
mask and substrate simultaneously for patterning. The
radiation source provides imaging beam and non-imaging beam, each of
fluence below the threshold of sequential lateral solidification, but with aggregate
fluence above the threshold. The imaging beam path includes a relatively delicate 1:1
mask and 1:1 projection subsystem, with optical elements including a final fold mirror
proximate to the
substrate surface, put the below-threshold mask pattern on the
substrate surface. The non-imaging beam bypasses the delicate elements of imaging beam path, passing through or around the final fold mirror, to impinge on the substrate surface at the same location. Where the
radiation patterns of the masked imaging beam and non-imaging beam coincide, their aggregate fluence exceeds the threshold for sequential lateral solidification. The dual selection provides pattern without damage to delicate optical elements.