Laser print patterning of planar spiral inductors and interdigitated capacitors

Abstract

This article describes direct laser printing of thin-film polymer onto rigid substrates for use as an etch mask or liftoff layer in patterning on-chip electrical components. Using this technique, the authors fabricated planar spiral inductors of 12×12mm2 with 2.5–5.5 turns producing series inductance Ls=80–180nH as well as planar interdigitated capacitors of 10×10mm2 with two to nine fingers producing series capacitance Cs=100–1600nF. This technique is a low cost, low temperature, rapid turn around, maskless, resist-free means of patterning device features as small as 130μm.