US 12,384,967 B2
Etchant
Shinhyuk Yang, Yongin-si (KR); Beomsoo Kim, Iksan-si (KR); Hyeonsu Cho, Iksan-si (KR); Yujin Kim, Yongin-si (KR); Jeehoon Kim, Yongin-si (KR); Youngjin Yoon, Iksan-si (KR); Eunwon Lee, Iksan-si (KR); and Donghan Kang, Yongin-si (KR)
Assigned to Samsung Display Co., Ltd., Yongin-si (KR); and DONGWOO FINE-CHEM Co., Ltd., Iksan-si (KR)
Filed by Samsung Display Co., Ltd., Yongin-si (KR); and DONGWOO FINE-CHEM Co., Ltd., Iksan-si (KR)
Filed on Feb. 15, 2023, as Appl. No. 18/169,798.
Claims priority of application No. 10-2022-0034935 (KR), filed on Mar. 21, 2022.
Prior Publication US 2023/0295501 A1, Sep. 21, 2023
Int. Cl. C09K 13/06 (2006.01)
CPC C09K 13/06 (2013.01) 20 Claims
OG exemplary drawing
 
1. An etchant comprising:
persulfate;
a fluorine-containing compound;
a chlorine-containing compound;
a cyclic amine compound;
an inorganic acid;
sulfate; and
water,
wherein,
a tip control index (Y) of the etchant is a value of at least about 45.0 and not more than about 70.0,
the tip control index (Y) being a value calculated by <Equation 1>:
Y=1.0×10−3×M(X1)+1.0×10−1×M(X2)+5.0×10−2×M(X3)+1.5×M(X1)×M(X2)+2.0×10−1×M(X1)×M(X3)+2.0×10−1×M(X2)×M(X3)  Equation 1
wherein, in Equation 1,
M(X1) indicates wt % of the chlorine-containing compound with respect to 100 wt % in total of the etchant,
M(X2) indicates wt % of the sulfate with respect to 100 wt % in total of the etchant, and
M(X3) indicates wt % of the water with respect to 100 wt % in total of the etchant.