Electron Vision Corporation

Alliedsignal Inc.

Jason P Minter

William R Livesay

John R Lee

A process for forming T-shaped metal contacts on a dielectric substrate. The process includes deposition of first and second photoresist layers onto a substrate; individually overall electron beam exposure of both layers; with subsequent imagewise UV exposure and development of both layers to form hollow cavities in the layers. By concentrating the electron beam radiation on the mid-point in the thickness of each photoresist layer, the radiation is distributed throughout each layer, resulting in solubility properties which lead to the formation of hollow cavities of a certain desired shape. In one embodiment of the invention, three-dimensional structures are formed in the photoresist layers by filling the hollow cavities with metal. Subsequent removal of unwanted portions of the photoresist layers produces a dielectric substrate having T-shaped metal contacts on its surface.

Method of creating optimal photoresist structures used in the manufacture of metal T-gates for high-speed semiconductor devices

A process for forming a photoresist image on a substrate and a process for forming metal contacts on a substrate are described. The process of forming a photoresist image includes depositing a positive working photoresist composition onto a metal layer which is on a substrate to thereby form a photoresist layer then imagewise exposing the photoresist layer to actinic radiation and developing said photoresist layer to form a plurality of cavities through the photoresist layer thereby revealing portions of the metal layer. Then the inventions provides for etching away the revealed portions of the metal layer followed by an overall exposing both the substrate and the remaining photoresist layer and remaining metal layer portions to sufficient electron beam radiation to render a part of the photoresist layer directly adjacent to the metal layer more soluble in a developer than the balance of the photoresist layer. Finally, the more soluble part of the photoresist layer is partially developed to thereby expand the cavities to form notches in the photoresist layer directly adjacent to the metal layer. In order to form the metal contacts of the present invention the invention provides for the further steps of depositing a metal into said cavities and notches to thereby form a conductive attachment to said metal contacts and removing the remaining photoresist and any metal which is not attachment-forming to thereby form metal contacts on the substrate. Microelectronic devices prepared by the same process are also disclosed.

Method of creating controlled discontinuity between photoresist and substrate for improving metal lift off

A process for forming a photoresist image on a substrate and a process for forming metal contacts on a substrate are described. The process of forming a photoresist image includes depositing a positive working photoresist composition onto a semiconductor substrate to thereby form a photoresist layer having a proximal surface on the substrate and a distal surface spaced from the substrate; imagewise exposing the photoresist layer to actinic radiation and developing said photoresist layer to form a plurality of cavities through the photoresist layer extending to the substrate; overall exposing the remaining photoresist layer portion to sufficient electron beam radiation concentrated within said remaining photoresist layer between the proximal and distal surfaces to render a part of said remaining photoresist layer more soluble than prior to exposure; developing the more soluble part of the remaining photoresist layer to thereby expand the cavities to form notches in said remaining photoresist layer between the proximal and distal surfaces to form a notched photoresist layer; overall exposing the notched photoresist layer to sufficient electron beam radiation concentrated at and above the mid-point of the notches to render the notched photoresist layer above the notches more soluble than prior to exposure; and developing the more soluble part of the notched photoresist layer resulting from the prior step to remove the upper portion of the notched photoresist layer above the midpoint of the notches to thereby form champagne glass-shaped cavities in the photoresist layer. In order to form the champagne glass-shaped metal contacts of the present invention the further steps of depositing a metal into said champagne glass-shaped cavities and removing the remaining photoresist and any metal which is not contact-forming to thereby form metal contacts on the substrate. Microelectronic devices prepared by the same process are also disclosed.

Growing community of inventors

San Diego, CA, United States of America

Jason P Minter