Deep dielectric isolation by fused glass
AssigneeInternational Business Machines Corporation
InventorsWei-Kan Chu, William A. Pliskin, Jacob Riseman
Life of this patent
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Abstract
Deep dielectric isolation zones in a substrate are achieved by forming trenches using reactive ion etching. A glass having a coefficient of thermal expansion closely matching that of the substrate is deposited onto the trench to entirely or partially fill the trench. Deposition can be by sedimentation, centrifugation or spin-on techniques. The structure is then fired until the glass particles fuse into a continuous glass layer and final smoothing if necessary can be accomplished.
Claims14
A method for forming high density dielectric isolation in an integrated circuit structure comprising the steps of:
- forming trenches having substantially vertical sidewalls in a silicon substrate;
- filling the trenches with suspension containing particles of glass having a coefficient of thermal expansion substantially the same as the substrate;
- firing the structure at a temperature high enough to fuse the particles of glass and to form a continuous glass layer in the trenches;
- and
- simultaneously planarizing the surface of said integrated circuit structure.
Dependencies are inferred from the claim text.