title: Mask-less ultraviolet photolithography based on CMOS-driven micro-pixel light emitting diodes.
abstract: We report on an approach to ultraviolet (UV) photolithography and direct writing where both the exposure pattern and dose are determined by a complementary metal oxide semiconductor (CMOS) controlled micro-pixellated light emitting diode array. The 370 nm UV light from a demonstrator 8 x 8 gallium nitride micro-pixel LED is projected onto photoresist covered substrates using two back-to-back microscope objectives, allowing controlled demagnification. In the present setup, the system is capable of delivering up to 8.8 W/cm2 per imaged pixel in circular spots of diameter approximately 8 microm. We show example structures written in positive as well as in negative photoresist.
authors.affiliation: Institute of Photonics, University of Strathclyde, Glasgow G4 0NW, UK.
authors.forename: D
authors.initials: D
authors.lastname: Elfström
authors.forename: B
authors.initials: B
authors.lastname: Guilhabert
authors.forename: J
authors.initials: J
authors.lastname: McKendry
authors.forename: S
authors.initials: S
authors.lastname: Poland
authors.forename: Z
authors.initials: Z
authors.lastname: Gong
authors.forename: D
authors.initials: D
authors.lastname: Massoubre
authors.forename: E
authors.initials: E
authors.lastname: Richardson
authors.forename: B R
authors.initials: BR
authors.lastname: Rae
authors.forename: G
authors.initials: G
authors.lastname: Valentine
authors.forename: G
authors.initials: G
authors.lastname: Blanco-Gomez
authors.forename: E
authors.initials: E
authors.lastname: Gu
authors.forename: J M
authors.initials: JM
authors.lastname: Cooper
authors.forename: R K
authors.initials: RK
authors.lastname: Henderson
authors.forename: M D
authors.initials: MD
authors.lastname: Dawson
mesh_terms: D017076:Computer-Aided Design; D004867:Equipment Design; D019544:Equipment Failure Analysis; D008029:Lighting / Q000295:instrumentation*; D008420:Manufactured Materials / Q000528:radiation effects*; D008904:Miniaturization; D010777:Photochemistry / Q000295:instrumentation*; D010781:Photography / Q000295:instrumentation*; D012666:Semiconductors; D014466:Ultraviolet Rays