Patent ID: 9359683
Filing Date: 2016-06-07
CPC Classification: C25D,H01L

Claim Text:
1. A method of forming a metal feature by plating through a patterned dielectric layer in an electroplating bath, the method comprising: providing a microfeature workpiece that includes a substrate having a continuous metal seed layer disposed on the substrate and a dielectric layer patterned on the metal seed layer to provide a recess defining sidewall surfaces and a bottom surface, wherein the bottom surface of the recess is a metal surface and the sidewall surfaces of the recess are dielectric surfaces; providing an electroplating bath in contact with an electrode; contacting the microfeature workpiece with the electroplating bath; applying an electric potential between the metal seed layer and the electrode and producing a first current density; electrochemically depositing a first metal layer within the recessed feature on an exposed top surface of the metal seed layer at a first deposition rate in the same electroplating bath; adjusting the electric potential to change the first current density to a second current density, wherein the second current density is increased from the first current density in the electroplating bath; electrochemically depositing a second metal layer within the same recessed feature on the exposed top surface of the first metal layer at a second deposition rate in the same electroplating bath, wherein the second deposition rate is greater than the first deposition rate; adjusting the electric potential to change the second current density to a third current density, wherein the third current density is increased from the second current density in the electroplating bath; and electrochemically depositing a third metal layer within the same recessed feature on the exposed top surface of the second metal layer at a third deposition rate in the same electroplating bath, wherein the third deposition rate is greater than the second deposition rate, wherein the first metal layer is deposited to a first depth, the second metal layer is deposited to a second depth, and the third metal layer is deposited to a third depth, wherein the first, second, and third current densities achieve an increasing deposition rate at the first, second, and third depths, wherein the metal in the metal layers is a metal alloy, wherein the first, second, and third current densities achieve a substantially constant weight ratio of alloying metals in the first, second, and third metal layers, and wherein the depth of the recess is in the range of about 21 microns to 134 microns.