Journal of the Electrochemical Society vol:158 issue:2 pages:H150-H155
Wet processes using organic solvents are gaining a renewed interest for stripping high dose (>= 1 x 15 atoms. cm(-2)) ion-implanted photoresist (II-PR) in front-end-of-line semiconductor manufacturing because of their excellent selectivity to ultrashallow implanted substrates and novel materials. However, the highly cross-linked resist layer (so-called crust), formed on the top and sidewalls of the resist has very limited solubility in organic solvents unlike the underlying nonimplanted resist (bulk). This study investigates the effect of UV pre- and post-treatment on II-PR for enabling its removal by organic solvent. Moreover, the impact of the UV wavelength, dose, and power density on the crust and bulk is presented. Optimal conditions of the UV pre- and post-treatment can be determined. Short (< 200 nm) and long wavelengths (300-400 nm) at low doses induce more scission of the crust with less cross-linking of the bulk, resulting in higher solubility of the II-PR in organic solvents. Moreover, the short wavelength pretreatment is advised because of its bigger effect on the crust, resulting in significant enhancement of the residue removal. In addition, a post-treatment using short wavelengths has high removal efficiency in contrast to the long wavelengths treatment. Finally, no significant impact of the power density is revealed. (C) 2010 The Electrochemical Society. [DOI: 10.1149/1.3524275] All rights reserved.