Process for forming tapered trenches in a dielectric material
AssigneesSTMicroelectronics S.r.l., Ovonyx, Inc.
InventorAlessandro Spandre
Life of this patent
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Abstract
A process for forming a tapered trench in a dielectric material includes the steps of forming a dielectric layer on a semiconductor wafer, and plasma etching the dielectric layer; during the plasma etch, the dielectric layer is chemically and physically etched simultaneously.
Claims23
A process for forming a tapered trench in a dielectric material, comprising the steps of forming a dielectric layer on a semiconductor wafer, and plasma etching said dielectric layer to form the tapered trench in the dielectric layer, wherein said step of plasma etching comprises chemically etching and physically etching said dielectric layer simultaneously and wherein said step of plasma etching comprises supplying a mixture of etchants comprising a boron halide and chlorine, the boron halide being the etchant that is dominant.
A process for forming a tapered trench in a dielectric material, comprising the steps of forming a dielectric layer on a semiconductor wafer, and plasma etching said dielectric layer to form the tapered trench in the dielectric layer, wherein said step of plasma etching comprises chemically etching and physically etching said dielectric layer simultaneously, wherein said step of plasma etching comprises supplying an etchant mixture comprising a boron halide, and wherein said etchant mixture contains 58% of BCl3, 38% of Cl2 and 4% of CHF3.
A process for manufacturing a phase change memory cell, comprising the step of forming a tapered trench in a dielectric layer and filling said tapered trench with a phase change material, wherein said step of forming a tapered trench includes simultaneously plasma etching said dielectric layer chemically and physically, and wherein said step of plasma etching comprises supplying an etchant mixture comprising a boron halide.
A process for manufacturing a phase change memory cell, comprising the step of forming a tapered trench in a dielectric layer and filling said tapered trench with a phase change material, wherein said step of forming a tapered trench includes simultaneously plasma etching said dielectric layer chemically and physically, wherein the step of plasma etching includes providing an etchant mixture comprising a boron halide, and wherein said etchant mixture contains 58% of BCl3, 38% of Cl2 and 4% of CHF3.
A process for forming a tapered trench, comprising:
- forming a dielectric layer;
- and
- plasma etching the dielectric layer to form the tapered trench in the dielectric layer by using an etchant mixture that includes a boron halide, wherein said etchant mixture contains 58% of BCl3, 38% of Cl2 and 4% of CHF3.
Dependencies are inferred from the claim text.