US 12,293,943 B2
Gold through silicon mask plating
Lee Peng Chua, Beaverton, OR (US); Defu Liang, Wilsonville, OR (US); Jacob Kurtis Blickensderfer, Tualatin, OR (US); Thomas A Ponnuswamy, Sherwood, OR (US); Bryan L. Buckalew, Tualatin, OR (US); and Steven T. Mayer, Aurora, OR (US)
Assigned to Lam Research Corporation, Fremont, CA (US)
Appl. No. 17/430,617
Filed by Lam Research Corporation, Fremont, CA (US)
PCT Filed Feb. 13, 2020, PCT No. PCT/US2020/018106
§ 371(c)(1), (2) Date Aug. 12, 2021,
PCT Pub. No. WO2020/168074, PCT Pub. Date Aug. 20, 2020.
Claims priority of provisional application 62/805,604, filed on Feb. 14, 2019.
Prior Publication US 2022/0216104 A1, Jul. 7, 2022
Int. Cl. H01L 21/768 (2006.01); C25D 3/48 (2006.01); C25D 5/02 (2006.01); C25D 7/12 (2006.01); C25D 17/06 (2006.01); H01L 21/311 (2006.01); H01L 23/48 (2006.01)
CPC H01L 21/76873 (2013.01) [C25D 3/48 (2013.01); C25D 5/022 (2013.01); C25D 7/123 (2013.01); C25D 17/06 (2013.01); H01L 21/31144 (2013.01); H01L 21/76877 (2013.01); H01L 21/76898 (2013.01); H01L 23/481 (2013.01)] 12 Claims
OG exemplary drawing
 
1. A method for etch assisted gold (Au) through silicon mask plating (EAG-TSM), the method comprising:
providing a seed layer on a substrate;
providing a silicon mask on at least a portion of the seed layer on the substrate, the silicon mask including one or more via to be filled with Au;
subjecting the masked substrate to at least one processing cycle, each processing cycle including an Au electroplating sub-step and a chemical etch treatment sub-step; and
repeating the at least one processing cycle for a number of repeated cycles until a selected via fill thickness is achieved, wherein each repeat of the at least one processing cycle includes an alternation between the Au electroplating sub-step and the chemical etch treatment sub-step,
wherein in each Au electroplating sub-step, residual Au is deposited on the silicon mask along with a deposition of the Au in the one or more via, the residual Au partially blocking the one or more via; and
wherein in each chemical etch treatment sub-step, residual Au deposited on the silicon mask is etched away to unblock the one or more via for the deposition of the Au in the one or more via in the Au electroplating sub-step of a succeeding processing cycle.