Structures with convex cavity bottoms
AssigneeTaiwan Semiconductor Manufacturing Company, Ltd.
InventorsYu-Lien Huang, Wei Hsiang Chan
Life of this patent
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Abstract
Provided are conductive structures located within dielectric material, and methods for fabricating such structures and devices. An exemplary method includes providing a substrate having a conductive feature in a first dielectric layer; depositing a second dielectric layer over the conductive feature and the first dielectric layer; etching the second dielectric layer to form a cavity through the second dielectric layer, wherein the cavity has a bottom with a convex profile; depositing a barrier layer along the bottom of the cavity; and depositing a conductive material in the cavity to form a structure electrically connected to the conductive feature.
Claims20
A method comprising:
- performing an etching process to etch a material to form a trench bound by a trench sidewall formed from the material and a convex trench bottom surface formed from the material, wherein the material has an upper surface, wherein the trench sidewall extends downward from the upper surface and intersects the convex trench bottom surface at a trench corner at a first depth below the upper surface;
- etching the material through a portion of the convex trench bottom surface to form a via bound by a via sidewall;
- depositing a barrier layer along the trench sidewall, along remaining portions of the convex trench bottom surface, and along the via sidewall, wherein a convex profile of the convex trench bottom surface is configured to facilitate formation of the barrier layer as a continuous barrier layer without voids or disconnections at the trench corner;
- and
- forming a conductive structure over the barrier layer in the trench and the via.
A method comprising:
- providing a substrate having a dielectric layer;
- and
- performing an etching process to etch the dielectric layer to form a cavity with a sidewall and having a bottom with a convex profile, wherein the etching process comprises a plasma etching process performed with a pressure of from 3 to 150 milliTorr (mTorr), a temperature of from −80 to 140° C., and a RF bias power of greater than 30 watts that causes ions to reflect from the sidewall and re-impinge on the dielectric layer adjacent to the sidewall to form micro-trenching, and wherein the convex profile of the bottom results from the micro-trenching.
A method comprising:
- performing an etching process to etch a material to form a first trench bound by a first trench sidewall formed from the material and a first convex trench bottom surface formed from the material and to form a second trench bound by a second trench sidewall formed from the material and a second convex trench bottom surface formed from the material, wherein the first trench has a first width and the second trench has a second width, wherein a ratio of the first width to the second width is from 1.5:1 to 20:1.
Dependencies are inferred from the claim text.