In this paper we report on surface nitridation of SiO2 and on photoresist removal by using species decomposed from NH3 or H-2 and generated by a heated tungsten catalyzer. The top surface of SiO2/Si(100) is nitrided at temperatures as low as 300 degreesC using species decomposed from NH3 species. The removal of heavy-doped, as high as 1 X 10(16) cm(-2), ion-implanted photoresist is realized using atomic hydrogen. (C) 2003 Elsevier Science B.V. All rights reserved.