Structural effects of diazonaphthoquinone-based dissolution inhibitors in photolithographic performance

In order to investigate the hydrogen bonding effect of the dissolution inhibitor, 2,4-di(5-sulfonyloxymethyl-l-oxo-2-diazonaphthalene)-3-hydroxybenzophen-one and 4,4'-di(5-sulfonyloxymethyl-1-oxo-2-diazonap-htha-lene)-2-hydroxy-benzophenone were synthesized, which were then mixed with (p-t-butylphenol- CH2O) novolak as resin. It is believed that the hydroxyl-carbonyl groups interaction in 4,4'-di(5- sulfonyloxymethyl-1-oxo-2-diazonaphthalene)-2-hydroxybenzophenone lead to a lower contrast compared to 2,4-di(5-sulfonyloxymethyl-1-oxo-2- diazonaphthalene)-3-hydroxybenzophenone at G-line (435nm) UV exposure. l,4-di(5-sulfonyloxymethyl-l-oxo-2-diazonaphthalene)bicyclo[2.2.1]heptane and 1,4-di(5-sulfonyloxymethyl-1-oxo-2-diazonaphthalene)cyclooctane were mixed with (p-t-butylphenol-CH2O) novolak as resin. Their lithographic performance were also compared under I-line (365nm) UV exposure. Undercut and notching problems occur in 1,4-di(5-sulfonyloxymethyl-l-oxo-2- diazonaphthalene)bicyclo[2.2.1]heptane but not in 1,4-di(5-sulfonyloxy-methyl- 1-oxo-2-diazonaphthalene)cyclooctane. And it is believed that the ring effect, as well as the diazonapthoquinone content in the compound play an important role in the photoresist performance. In this research, the new photoresists with sub-micron resolution with a fairly high sensitivity were demonstrated