US 12,406,860 B2
Method of forming conductive layer of semiconductor device
Yu Shu Lin, Taoyuan (TW)
Assigned to NANYA TECHNOLOGY CORPORATION, New Taipei (TW)
Filed by NANYA TECHNOLOGY CORPORATION, New Taipei (TW)
Filed on Jul. 27, 2022, as Appl. No. 17/815,215.
Prior Publication US 2024/0038545 A1, Feb. 1, 2024
Int. Cl. H01L 21/3213 (2006.01)
CPC H01L 21/32136 (2013.01) [H01L 21/32139 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A method of forming a conductive layer of a semiconductor device, comprising:
forming a hard mask layer on a metal layer overlying a substrate, wherein the metal layer comprises tungsten;
patterning the hard mask layer until portions of the metal layer are exposed from the patterned hard mask layer; and
performing a plasma process to the metal layer through the patterned hard mask layer until portions of the substrate are exposed from the etched metal layer, wherein a process gas mixture used in the plasma process comprises a fluorine based gas, a chlorine based gas, and oxygen, wherein the performing the plasma process comprises a first stage and a second stage, the first stage is conducted at a first bias voltage supplied in a first pulse waveform having a first amplitude, the second stage is conducted at a second bias voltage supplied in a second pulse waveform having a second amplitude, the second amplitude is greater than the first amplitude, and the first bias voltage and the second bias voltage are in a range from about 150 V to about 400 V.