Method and apparatus for enhancing resist sensitivity and resolution by application of an alternating electric field during post-exposure bake

A method of forming a patterned material structure on a substrate, the substrate being selected from the group consisting of semiconductors, ceramics and metals, the method comprising:

• (a) optionally providing the substrate with an underlayer;
• (b) applying a positive photoresist composition to the substrate or underlayer-coated substrate to form a photoresist layer, said photoresist composition comprising a radiation-sensitive acid generator;
• (c) optionally coating the photoresist layer with a protective co ting;
• (d) patternwise exposing the substrate to radiation whereby acid is generated by the radiation-sensitive acid generator in exposed regions of the photoresist layer;
• (e) subjecting the exposed photoresist layer to postexposure being while applying an alternating electric field so as to form a latent, patterned image in the film, wherein the alternating electric field has a peak-to-peak voltage of 2V;
• (f) contacting the substrate with an aqueous alkaline developer solution, whereby the exposed regions of the photoresist layer are selectively dissolved by the developer solution to reveal a resist structure pattern;
• and
• (g) transferring the resist structure pattern to the substrate by etching into the substrate or underlayer-coated substrate through spaces in the resist structure pattern.

A method of forming a patterned material structure on a substrate, the material being selected from the group consisting of semiconductors, ceramics and metals, the method comprising:

• (a) optionally providing the substrate with an underlayer;
• (b) applying a negative photoresist composition to the substrate or underlayer-coated substrate to form a photoresist layer, said photoresist composition comprising a resist binder, radiation-sensitive acid generator and a crosslinking agent effective to crosslink the resist binder;
• (c) optionally coating the photoresist layer with a protective co ting;
• (d) patternwise exposing the substrate to radiation whereby acid is generated by the radiation-sensitive acid generator in exposed regions of the photoresist layer;
• (e) subjecting the exposed photoresist layer to postexposure being while applying an alternating electric field so as to form a latent, patterned image in he photoresist layer, wherein the alternating electric field has a peak-to-peak voltage of 2V;
• (f) contacting the photoresist layer with an aqueous alkaline developer solution, whereby the exposed regions of the photoresist layer are selectively dissolved by the developer solution to reveal a resist structure pattern;
• and
• (g) transferring the negative resist structure pattern to the substrate by etching into the substrate or underlayer-coated substrate through spaces in the negative resist structure pattern.

In a method for generating a resist image on a substrate comprising

• (a) coating a substrate with a photoresist composition comprised of a resist binder and a radiation-sensitive acid generator;
• (b) exposing the resist selectively to a predetermined pattern of radiation;
• (c) baking the exposed resist;
• and
• (d) developing the latent image so formed with a developer,
• the improvement comprising applying an alternating electric field to the resist during step (c), wherein the alternating electric field has a peak-to-peak voltage of 2V.