Theoretical and Experimental Study of Thymine Based Photoresists Polymers

J VICH BERLANGA; C LUCIANI; D. M. MARTINO; D. A. ESTENOZ; G. MEIRA

Viña del Mar

Simposio; ARCHIPOL 2007 IV Simpósio Binacional de Polímeros Argentino-Chileno; 2007

Styrene-based biopolymers containing ionic and thymine groups chemically attached to the polystyrene structure were experimental- and theoretically investigated. The ionic groups make the polymer watersoluble, eliminating the environmental and health concerns associated with the use of volatile organic solvents as in conventional photoresist processes. When biopolymers are illuminated with UV light, a photocyclization reaction between adjacent thymines takes place, rendering it water-insoluble. The material obtained is called a photoresist. Vinylbenzyl thymine (VBT) was copolymerized in a batch solution process with vinylbenzyl triethylammonium chloride (VBA) orvinylphenylsulfonic acid sodium salt (SSA), using different comonomers ratios and initiatorconcentrations. The reactions were carried out at 65 C in a batch-stirred tank reactor using 2,2’-azobisisobutyronitrile (AIBN) as initiator and isopropanol as solvent.