Disclosed is a method and apparatus for mitigation of photoresist line pattern collapse in a photolithography process by applying a gap-fill material treatment after the post-development line pattern rinse step. The gap-fill material dries into a solid layer filling the inter-line spaces of the line pattern, thereby preventing line pattern collapse due to capillary forces during the post-rinse line pattern drying step. Once dried, the gap-fill material is depolymerized, volatilized, and removed from the line pattern by heating, illumination with ultraviolet light, by application of a catalyst chemistry, or by plasma etching.