Lithographic dry development using optical absorption
AssigneeThe Regents of the University of California
InventorsDeirdre Olynick, P. James Schuck, Martin Schmidt
Life of this patent
Estimating the term…
Abstract
A novel approach to dry development of exposed photo resist is described in which a photo resist layer is exposed to a visible light source in order to remove the resist in the areas of exposure. The class of compounds used as the resist material, under the influence of the light source, undergoes a chemical/structural change such that the modified material becomes volatile and is thus removed from the resist surface. The exposure process is carried out for a time sufficient to ablate the exposed resist layer down to the layer below. A group of compounds found to be useful in this process includes aromatic calixarenes.
Claims23
A process for lithographic development comprising:
- (i) depositing a layer of a resist material on a substrate;
- (ii) exposing a region of the resist material to a source of high-resolution radiation;
- (iii) exposing the resist material to a light source wherein the region exposed to the high-resolution radiation is volatilized.
A process for lithographic exposure and development comprising:
- (i) depositing a layer of a resist material on a substrate;
- (ii) exposing a region of the resist material to a source of high-resolution radiation for a limited period of time to only partially change the solubility characteristics of the resist;
- (iii) further exposing the resist material to a light source to continue the chemical modification initiated by the high resolution source to complete the change in solubility;
- and thereafter,
- (iv) wet developing the resist material to reveal the high resolution pattern created in the preceding steps.
A composition of matter suitable for use as a photoresist material, wherein said material is a strong absorber in the visible light range, such that in those areas of exposure to visible light, the composition of matter undergoes a chemical change to thus modify its volatility, the contrast in volatility between the exposed and unexposed portions of the resist material sufficient to allow for the preferential volatilization of the exposed material under the influence of a laser light.
A dry lithography process in which:
- i) a resist layer is first deposited on a substrate;
- ii) the resist layer is exposed to an electron high resolution radiation beam to pattern the resist;
- and,
- iii) the patterned resist is thereafter dry developed with a laser to volatilize the resist in the areas of exposure.
Dependencies are inferred from the claim text.