Disclosed is a negative-working photolithographic patterning material consisting of a substrate and a negative-working photoresist layer having a relatively large thickness on the substrate surface which is suitable for the formation of a patternwise masking layer in a patternwise ion-implantation or metal plating treatment. The negative working photoresist layer is formed from a negative-working chemical amplification photoresist composition comprising an alkali-soluble resinous ingredient, a radiation-sensitive acid-generating agent and a crosslinking agent, of which the alkali-soluble resinous ingredient is a m-cresol novolak resin prepared by the acid-catalyzed condensation reaction of formaldehyde and m-cresol alone as the phenolic reactant or a combination of such a m-cresol novolak resin and a polyhydroxystyrene resin of which at least 50% by weight is the m-cresol novolak resin.