Two step metallization formation
AssigneeTaiwan Semiconductor Manufacturing Company, Ltd.
InventorsYa-Lien Lee, Chun-Chieh Lin
Life of this patent
Estimating the term…
Abstract
An integrated circuit structure includes a first conductive line, a dielectric layer over the first conductive line, a diffusion barrier layer in the dielectric layer, and a second conductive line in the dielectric layer. The second conductive line includes a first portion of the diffusion barrier layer. A via is underlying the second conductive line and electrically couples the second conductive line to the first conductive line. The via includes a second portion of the diffusion barrier layer, with the second portion of the diffusion barrier layer having a bottom end higher than a bottom surface of the via.
Claims20
A method comprising:
- forming a first conductive line over and electrically connected to a semiconductor device;
- forming an etch stop layer over the first conductive line;
- depositing a first dielectric layer over the etch stop layer;
- etching a via opening in the first dielectric layer;
- etching a plurality of trenches in the first dielectric layer while extending the via opening through the first dielectric layer;
- filling a portion of the via opening with a first conductive material, the first conductive material being a first metallic material doped with an additive element;
- depositing a diffusion barrier layer over bottoms and along sidewalls of the trenches, over the first conductive material in the via opening, and along exposed sidewalls of the via opening;
- removing portions of the diffusion barrier layer over the first conductive material in the via opening;
- and
- filling the trenches and remaining portions of the via opening with a second conductive material.
A method comprising:
- forming a dielectric layer over a first conductive line;
- forming a via opening in the dielectric layer, the first conductive line exposed by the via opening;
- filling a first portion of the via opening with a first conductive material, the first conductive material comprising at least two conductive elements;
- forming a diffusion barrier layer along sidewalls of a second portion of the via opening;
- filling the second portion of the via opening with a second conductive material;
- and
- annealing the first conductive material, the annealing diffusing at least one of the conductive elements into the dielectric layer to form a dielectric barrier layer along sidewalls of the first portion of the via opening.
A method comprising:
- forming a dielectric layer over a first conductive line;
- forming a trench and a via opening in the dielectric layer, with the first conductive line exposed to the via opening;
- filling a lower part of the via opening with a first conductive material to form a lower part of a via;
- after the lower part of the via opening is formed, forming a diffusion barrier layer at a bottom and sidewalls of the trench, and at a bottom and sidewalls of the via opening;
- and
- after the forming the diffusion barrier layer, filling an upper part of the via opening with a second conductive material to form an upper part of the via.
Dependencies are inferred from the claim text.