Photoresist integrity and outgassing effects during plasma immersion ion implantation

Plasma immersion ion implantation (PIII) has been evaluated for process compatibility with photoresists. The effects of non-mass-separated ion implantation into bare Si, soft-baked (SE), hardbaked (HE), and UV/baked (UVB) patterned photoresist wafers are discussed. Outgassing of the photoresist can cause co-implantation of unintended species since the plasma will ionize these by-products. SIMS analysis was used to characterize dopant profiles and implanted C, O, and N from outgassed photoresist species. Acceptable levels of carbon are shown for a range of implants. Correlation between RGA and SIMS data shows that UVB photoresist outgasses increased amounts of CO and CO/sub 2/ during PIII implantation compared to the SB and HB photoresist. The PIII implants showed no damage to photoresist features or dimensions, as quantified with SEM cross-sectional analysis.