Near-field optical photomask repair with a femtosecond laser.
We present a high-resolution near-field optical tool designed for repair of opaque defects in binary photomasks. Both instrument design and near-field imaging and patterning results will be presented. Designed for ablative processing of thin metal films, the MR-100 incorporates an industrial amplified femtosecond laser, third harmonic generator and built-in autocorrelator. The ultrashort duration of the femtosecond pulses enables the tool to remove chrome layers with negligible damage to the surrounding metal or the underlying quartz substrate. The micropipette based near-field writing head can deliver power densities of hundreds of GW/cm2 to spots of several hundred nanometres and below. Repairs on sample masks will be presented and the repair quality will be discussed.
Lieberman
K
K
Nanonics Lithography Ltd., Malcha, Jerusalem, Israel. klony@netvision.net.il
Shani
Y
Y
Melnik
I
I
Yoffe
S
S
Sharon
Y
Y