Characterization of a polymer microlens fabricated by use of the hydrophobic effect

We report a means of fabricating hydrophilic domains in a hydrophobic backg round by lithographically patterning an adhesive hydrophobic layer. Polymer microlenses were fabricated on these substrates by use of a dip-coating te chnique. Various lens shapes (circular, elliptical, square) were fabricated on a variety of substrates (SiO2, SiN, GaAs, InP, etc.), ranging in size f rom 2 to 500 mu m in diameter, with fill factors of up to 90%. Plano-convex and double-convex lenses were fabricated, with f-numbers as low as 1.38 an d 1.2, respectively. Optimum lens surfaces deviated from spherical by just +/-5 nm. The lenses are stable at room temperature and exhibit minimal degr adation after 24 h at 105 degrees C. The transfer of these polymer lenses t o an underlying substrate was also demonstrated. (C) 2000 Optical Society o f America.