Antireflective coating process
AssigneesShipley Company, L.L.C., Sematech, Inc.
InventorsJohn S. Petersen, Kim R. Dean, Daniel A. Miller
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Abstract
Reduction of reflection from an integrated circuit substrate during exposure of a photoresist layer on a surface such as an integrated circuit wafer is minimized by incorporating an antireflective coating between the photoresist layer and the integrated circuit substrate. The antireflective layer, after exposure and development of the photoresist layer, is preferably removed by exposing the non-masked antireflective layer to activating radiation while heating the coating to induce a solubilizing reaction in an antireflective coating and a curing reaction in an overlying photoresist mask. Thereafter, the exposed portions of the antireflective layer are removed by treatment with a suitable developer.
Claims22
A process for reducing reflection from a substrate during imaging of a photoresist layer, said process comprising the steps of forming an antireflective, radiation-adsorbing coating over a substrate;
- applying a radiation-sensitive photoresist layer over said antireflective coating, said antireflective coating being capable of adsorbing activating radiation for said photoresist layer thus decreasing reflection of the same back into the photoresist layer;
- exposing said photoresist layer to activating radiation in an image pattern to form a latent image therein without formation of a developable latent image in the antireflective coating, developing said photoresist layer with a developer that is incapable of dissolving said antireflective coating to form a relief image in said photoresist layer, altering the dissolution properties of the antireflective coating;
- and dissolving said antireflective coating in a solvent therefor without appreciably dissolving the photoresist layer to bare the underlying substrate in an image pattern.
A process for reducing reflection from an integrated circuit substrate during imaging of a photoresist layer, said process comprising the steps of forming a polysulfone coating capable of adsorbing deep ultraviolet radiation over an integrated circuit substrate;
- applying a deep ultraviolet radiation-sensitive photoresist layer over said polysulfone coating;
- exposing said photoresist layer to deep ultraviolet radiation in an image pattern to form a latent image therein without formation of a developable latent image in the polysulfone layer;
- developing said photoresist layer with an aqueous alkaline developer that is incapable of dissolving said polysulfone coating to form a relief image in said photoresist layer;
- altering the dissolution properties of the polysulfone coating and the photoresist layer by exposing the same to deep ultraviolet irradiation while heating the same to render the polysulfone coating base soluble and cure the photoresist layer to thereby decrease its base solubility;
- and dissolving said polysulfone coating in an aqueous alkaline developer solution to bare the underlying substrate in an image pattern.
Dependencies are inferred from the claim text.