US 12,281,251 B2
Etching composition and method for selectively removing silicon nitride during manufacture of a semiconductor device
Jhih Kuei Ge, New Taipei (TW); Yi-Chia Lee, Chupei (TW); Wen Dar Liu, Chupei (TW); Aiping Wu, Chandler, AZ (US); and Laisheng Sun, Gilbert, AZ (US)
Assigned to Versum Materials US, LLC, Tempe, AZ (US)
Appl. No. 17/754,165
Filed by Versum Materials US, LLC, Tempe, AZ (US)
PCT Filed Sep. 28, 2020, PCT No. PCT/US2020/052999
§ 371(c)(1), (2) Date Mar. 25, 2022,
PCT Pub. No. WO2021/067150, PCT Pub. Date Apr. 8, 2021.
Claims priority of provisional application 62/908,083, filed on Sep. 30, 2019.
Prior Publication US 2022/0298182 A1, Sep. 22, 2022
This patent is subject to a terminal disclaimer.
Int. Cl. C09K 13/06 (2006.01); C07F 7/08 (2006.01); C07F 9/06 (2006.01); H01L 21/02 (2006.01); H01L 21/311 (2006.01)
CPC C09K 13/06 (2013.01) [C07F 7/0838 (2013.01); C07F 9/06 (2013.01); H01L 21/0217 (2013.01); H01L 21/31111 (2013.01); H01L 21/0206 (2013.01); H01L 21/02164 (2013.01)] 23 Claims
 
1. A composition comprising:
A. neat phosphoric acid;
B. approximately 30% or greater by weight of a mixture comprising at least one of:
I. a compound of Formula I:

OG Complex Work Unit Chemistry
wherein:
(i) m=0-20,
(ii) each of R1, R2, R3, R4 and R5 is independently selected from the group of hydrogen, a C1 to C10 linear alkyl group, a C1 to C10 linear alkyl group substituted with fluorine, a nitrogen-containing group, an oxygen-containing group, a C3 to C10 branched alkyl group, a C3 to C10 cyclic alkyl group, a C5 to C12 aryl group, a C2 to C10 linear or branched alkenyl group and a C2 to C10 linear or branched alkynyl group, custom characterOH, and
(iii) each of Ra and Rb is independently selected from a C1 to C10 linear alkyl group, a C3 to C10 branched alkyl group, a C3 to C10 cyclic alkyl group, a C5 to C12 aryl group, a C2 to C10 linear or branched alkenyl group and a C2 to C10 linear or branched alkynyl group, custom characterNH—C1-C10 alkyl, a C1-C10 alkyl substituted with custom characterOH; or
II. a compound of Formula II:

OG Complex Work Unit Chemistry
wherein:
(i) m=0-20,
(ii) n=0-20,
(iii) R3 is selected from the group of hydrogen, a C1 to C10 linear alkyl group, a C1 to C10 linear alkyl group substituted with fluorine, a nitrogen-containing group, an oxygen-containing group, a C3 to C10 branched alkyl group, a C3 to C10 cyclic alkyl group, a C5 to C12 aryl group, a C2 to C10 linear or branched alkenyl group and a C2 to C10 linear or branched alkynyl group, custom characterOH, Z1 and Z2, and
(iv) each of Ra and Rb is independently selected from a C1 to C10 linear alkyl group, a C3 to C10 branched alkyl group, a C3 to C10 cyclic alkyl group, a C5 to C12 aryl group, a C2 to C10 linear or branched alkenyl group and a C2 to C10 linear or branched alkynyl group, custom characterNH—C1-C10 alkyl, a C1-C10 alkyl substituted with custom characterOH,
(v) Z1 and Z2 are each independently selected from:
a.

OG Complex Work Unit Chemistry
b.

OG Complex Work Unit Chemistry
c. custom characterN+(CH3)3Cl, and
d. custom characterCH(OH)CH2OH; and
III. an aqueous solvent.
 
23. A method of selectively enhancing the etch rate of silicon nitride relative to silicon dioxide on a semiconductor substrate comprising silicon nitride and silicon dioxide, the method comprising the steps of:
a. contacting the semiconductor substrate comprising silicon nitride and silicon dioxide with the composition of claim 1; and
b. rinsing the semiconductor device after the silicon nitride is at least partially removed.