	US 11,955,341 B2
	Etching solution and method for selectively removing silicon nitride during manufacture of a semiconductor device
Jhih Kuei Ge, New Taipei (TW); Yi-Chia Lee, Chupei (TW); and Wen Dar Liu, Chupei (TW)
Assigned to Versum Materials US, LLC, Tempe, AZ (US)
Appl. No. 17/432,992
Filed by Versum Materials US, LLC, Tempe, AZ (US)
PCT Filed Mar. 10, 2020, PCT No. PCT/US2020/021865 § 371(c)(1), (2) Date Aug. 23, 2021, PCT Pub. No. WO2020/185762, PCT Pub. Date Sep. 17, 2020.
Claims priority of provisional application 62/816,806, filed on Mar. 11, 2019.
Prior Publication US 2022/0157613 A1, May 19, 2022
Int. Cl. H01L 21/311 (2006.01); C09K 13/04 (2006.01); C09K 13/06 (2006.01); H01L 21/02 (2006.01); H01L 21/306 (2006.01); H01L 21/3213 (2006.01)

CPC H01L 21/31111 (2013.01) [C09K 13/04 (2013.01); C09K 13/06 (2013.01); H01L 21/02126 (2013.01); H01L 21/30604 (2013.01); H01L 21/32133 (2013.01); H01L 21/32134 (2013.01)]

17 Claims

1. An etching solution suitable for the selective removal of silicon nitride over silicon oxide from a microelectronic device, consisting of:

water;

about 59.5 to about 85 wt % neat phosphoric acid;

an organosilicon compound which is selected from the group consisting of trimethoxymethylsilane, dimethoxydimethylsilane, triethoxymethylsilane, diethoxydimethylsilane, trimethoxysilane, dimethoxymethylsilane, di-isopropyldimethoxysilane, diethoxymethylsilane, dimethoxyvinylmethylsilane, dimethoxydivinylsilane, diethoxyvinylmethylsilane and diethoxydivinylsilane;

silicic acid; and

a hydroxyl group-containing water-miscible solvent.