Back to results
US 6,806,196 B2Granted
High precision integrated circuit capacitors
AssigneeTexas Instruments Incorporated
InventorsBill Alan Wofford, Robert Nguyen
Life of this patent
Estimating the term…
Abstract
A polysilicon layer (30) is formed on a dielectric region (20). An optional metal silicide layer (50) can be formed on the polysilicon layer. A dielectric layer (60) is formed over the metal silicide layer and a conductive layer (70) formed over the dielectric layer. The formed layers are etched by a combination of multi-step dry and wet process to form high precision integrated circuit capacitors.
Claims7
A method for forming an integrated circuit capacitor in a trench, comprising:
- forming a trench in a semiconductor substrate;
- forming a first dielectric layer in said trench;
- forming a patterned polysilicon layer on said dielectric layer;
- forming a metal silicide on said polysilicon layer;
- forming a second dielectric layer over said metal silicide layer;
- forming a conductive layer over said dielectric layer;
- forming a hardmask layer over said conductive layer;
- etching said hardmask layer and partially etching said conductive layer using a dry etch process;
- and
- etching remaining conductive layer using a wet etch process.
7 more elements
Dependencies are inferred from the claim text.