POSITIVE PHOTORESIST Russian patent published in 1996 - IPC

FIELD: o-naphthoquinonediazide-base positive photoresists. SUBSTANCE: positive photoresist has, wt.-%: ether of naphthoquinonediazide sulfoacids and novolacs phenolformaldehyde resin (1fa) 3.57-12.86; novolacs phenolformaldehyde resin (2fa) 6.07-17.14; resol phenolformaldehyde resin (3fa) modified with colophony 1.07-3.18; butylated styromal or polycarbonate (plasticizer) 0.15-0.25; n-butanol (solvent) 8-12; dioxane (solvent) - the rest. (1fa) has structural formula: where n = 2-6; X - H or naphthoquinonediazide group at molecular mass 800-1800, content of naphthoquinonediazide groups is 35-42 wt.-%, bromine content is 17-21%; 2fa has structural formula where n = η and determined by dynamic viscosity of 50% spirituous solution (h = 150-200); drop point is 120-140 C; phenol mass part is 2%, not above; 3fa has structural formula , drop point is 80-95 C; gelatinization time at 150- C is 110-150 s. Butylated styromal has formula -CH(C₆H₅)-CH₂-CHK-CHM- where K - C(O)-OH; M - C(O)O-C₄H₉; molecular mass is 25000-30000; n = 90-110 mole%. Polycarbonate has formula where n = 10000-20000. Mass part of dry components in photoresist is 15.12-29.19%, content of naphthoquinonediazide groups in dry components is 10-18%, ratio of 3fa and 2fa = 1:(9-5). New photoresist shows maximal resolution capability using highly contrasting developing agents 0.7 mcm. Masking properties of photoresist film at level of internal porosity is less 0.05 defects/cm² (film microirregularity is 420 , not above). Also, photoresist improves adhesion, does not require additional adhesives at two-fold overdeveloping photoresist without linear dimension deviation and reexposition by 1.5-2-fold without negative deviations of dark photocopies member size. Enhanced quality of developed field, good masking at plasma etching any materials, backing purity and quick removal of photoresist tanned at 160 C. Photoresist shows broad range of thickness obtained 0.8-2.2 mcm. Photoresist is used in radioelectronics, microelectronics. EFFECT: enhanced quality of photoresist. 3 tbl