Positive resist image forming method

PURPOSE: To form a positive resist image on a substrate by using an arom. polymer resin, a crosslinking agent having the function of an acid catalyst and an acid generating agent. CONSTITUTION: A substrate is coated with a compsn. contg. a film forming arom. polymer resin having functional groups which activate the resin to electrophilic arom. substitution, a crosslinking agent having the function of an acid catalyst and forming carbonium ions at the time of reaction with an acid and a radiation-degradable acid generating agent which absorbs radiation for forming an image. The resultant film is imagewise exposed with medium or deep UV and the resin in the exposed part of the film is made dense. The film is then brought into contact with an org. metallic reagent, an org. metallizing agent is absorbed in the unexposed region having higher permeability and the film is etched with reactive ions to form a positive resist pattern.