The use of polymeric aperture masks to fabricate high performance pentacene-based integrated circuits is presented. The aperture masks are fabricated using a laser ablation process with capabilities of generating 10 Am features. A mask set consisting of 4-6 aligned layers has been fabricated and has been used to demonstrate functional rf-powered integrated circuits with 20 Am gate lengths. Devices consisted of shadow-mask patterned layers of gold, alumina, and pentacene. TFT mobilities greater than 2 cm(2)/V s were measured and propagation delays from 7-stage ring oscillators of less than 5 As were observed. This all-additive, dry patterning method has been extended to the production of samples as large as 6 in x6 in. Larger aperture masks are under investigation and continuing efforts are focused on automation of the alignment process. (C) 2004 American Vacuum Society.