DEEP UV PHOTOCHEMISTRY AND PATTERNING OF SELF-ASSEMBLED MONOLAYER FILMS

Patterned deep UV irradiation of organosilane self-assembled monolayer (SAM) films caused photocleavage of the organic groups in the molecule, and creates alternating regions of intact film and hydrophilic, surface silanol moieties. The exposed regions can undergo a second chemisorption reaction to produce an assembly of SAMs in the same molecular plane. The patterned SAM films can also act as a template for selective build-up of materials in the z-direction. The use of UV patterned silane SAM films as imaging layers for optical lithography has been demonstrated. The exposed films are selectively metallized using electroless deposition to produce a thin metal layer only in the unexposed areas. The film/metal assembly is a highly resistive barrier to reactive ion etching (RIE) for pattern transfer into the substrate. Features to 0.5-mu-m line width and working transistor test structures have been produced using this process.