Retention of mask edge integrity during MeV implants

The effect of increasing implant beam currents during MeV well implants on thick photoresist was evaluated in terms of critical dimension (CD) control and mask edge integrity, implant dosimetry, and post implant ashing. Hard bake, soft bake, and photostabilization pretreatments were quantified in terms of outgassing during implant, retention of mask edge integrity, and ability to ash without residues. The beam current of a 825 keV P implant (n-well) was successfully increased by a factor of four with no loss in CD control, implant or ashing performance.