Pulse electroplating copper or copper alloys
AssigneeAdvanced Micro Devices, Inc.
InventorsValery Dubin, Chiu Ting, Robin W. Cheung
Life of this patent
Estimating the term…
Abstract
High aspect ratio openings in excess of 3, such as trenches, via holes or contact holes, in a dielectric layer are voidlessly filled employing a pulse or forward-reverse pulse electroplating technique to deposit copper or a copper-base alloy. A leveling agent is incorporated in the electroplating composition to ensure that the opening is filled substantially sequentially from the bottom upwardly.
Claims16
A method of filling an opening in a dielectric layer forming part of an integrated circuit with copper or a copper alloy, the opening having a width and comprising lower and upper ends connected by a sidewall, with lower and upper corners formed at the respective intersections of the sidewall with the lower and upper ends, which method utilizes an electroplating composition and comprises the sequential steps of:
- (a) in a first, electroplating phase, cathodically depositing the copper or copper alloy to partially fill the opening with a layer having a thickness corresponding to about one-half (1/2) of the width of the opening;
- (b) in a second, electro-etching phase, anodically dissolving a portion of the deposited copper or copper alloy layer so that the remaining thickness of the deposited copper or copper alloy at the upper corners is the same as or less than at the sidewall;
- and
- (c) in a third, electroplating phase, substantially completely filling the opening by cathodic plating.
Dependencies are inferred from the claim text.