POLYIMIDE TYPE POSITIVE PHOTORESIST

PURPOSE: To improve the storage life by using a positive photoresist containing a polyamic acid polymer which can be completely esterified and changed into polyimide, one kind of radiation-sensitive quinone diazide compd. and other desired components in an org. solvent. CONSTITUTION: A base body is coated with a photoresist soln., and the layer is dried and exposed to UV rays of specified wavelength for an image, and the exposed layer is developed to remove the irradiated area by a water-base alkali developer soln. The obtd. relief structure is subjected to postbaking to form a relief structure of a polyimide prepolymer having durability against high temp. In this method, the positive photoresist used contains a completely esterified polyamic acid polymer which can be changed into polyimide and a radiation sensitive quinone diazide compd. Thereby. the storage life can be improved.