US 12,482,668 B2
Integrated circuit with getter layer for hydrogen entrapment
Marc L. Tarabbia, Austin, TX (US); Scott P. Warrick, Austin, TX (US); and Winston S. Blackley, Austin, TX (US)
Assigned to CIRRUS LOGIC, INC., Austin, TX (US)
Filed by CIRRUS LOGIC INTERNATIONAL SEMICONDUCTOR LTD., Edinburgh (GB)
Filed on Jan. 5, 2023, as Appl. No. 18/150,398.
Claims priority of provisional application 63/297,969, filed on Jan. 10, 2022.
Prior Publication US 2023/0223274 A1, Jul. 13, 2023
Int. Cl. H01L 21/322 (2006.01); H01L 21/02 (2006.01); H01L 21/311 (2006.01); H01L 21/56 (2006.01); H01L 21/70 (2006.01); H01L 23/31 (2006.01); H01L 23/522 (2006.01); H10D 1/47 (2025.01); H10D 86/85 (2025.01)
CPC H01L 21/3221 (2013.01) [H01L 21/02172 (2013.01); H01L 21/02337 (2013.01); H01L 21/31144 (2013.01); H01L 21/56 (2013.01); H01L 21/707 (2013.01); H01L 23/3107 (2013.01); H01L 23/5226 (2013.01); H10D 1/474 (2025.01); H10D 86/85 (2025.01)] 15 Claims
OG exemplary drawing
 
1. A method of reducing time-dependent variation of characteristics of thin-film resistors mounted or formed on a substrate of a semiconductor wafer during fabrication due to hydrogen absorption, the method comprising:
forming a first getter layer on the semiconductor wafer in mounting or formation areas of the thin-film resistors in die areas of the substrate;
forming a first insulating layer atop the first getter layer;
subsequent to the forming of the first getter layer, forming or mounting the thin-film resistors on the first insulating layer above the first getter layer above a top surface of the semiconductor wafer in the die areas of the substrate, wherein the thin-film resistors are of a material that absorbs hydrogen and exhibits an electrical characteristic change dependent on an amount of absorbed hydrogen;
forming semiconductor structures in the die areas;
forming a second insulating layer on a top surface of the thin-film resistors in the die areas;
forming a second getter layer on the second insulating layer from an insulating material; and
processing the semiconductor wafer with one or more processes exposing the semiconductor wafer to vapor having a hydrogen content, whereby an amount of hydrogen absorbed by the thin-film resistors is reduced by presence of the getter layer.