Photochemical production of oligothiophene and polythiophene micropatterns from 2,5-diiodothiophene on Au in UHV

Fabrication of oligothiophene and polythiophene micropatterns is demonstrated by photochemical reactions of 2,5-diiodothiophene adsorbed on an Au coated Si wafer under UHV conditions. For patterning, a TEM grid is utilized as a model stencil mask. Fluorescence microscopic analysis shows that polymer microstructures with good pattern fidelity are attained over a large area. RAIRS and NEXAFS analyses indicate that the electronic and molecular structures of the produced polymer are similar to those of chemically synthesized polythiophene. The structural defects of the photochemically produced polymer are negligible. The present procedure provides a very efficient strategy for growth and patterning of conjugated polymer microstructures with high quality in one step.