	US 12,256,489 B2
	Circuit board including a buffer layer for improving
Yong Suk Kim, Seoul (KR); Jeong Han Kim, Seoul (KR); and Moo Seong Kim, Seoul (KR)
Assigned to LG INNOTEK CO., LTD., Seoul (KR)
Appl. No. 17/928,703
Filed by LG INNOTEK CO., LTD., Seoul (KR)
PCT Filed Jun. 10, 2021, PCT No. PCT/KR2021/007255 § 371(c)(1), (2) Date Nov. 30, 2022, PCT Pub. No. WO2021/251763, PCT Pub. Date Dec. 16, 2021.
Claims priority of application No. 10-2020-0071606 (KR), filed on Jun. 12, 2020.
Prior Publication US 2023/0240005 A1, Jul. 27, 2023
Int. Cl. H05K 1/02 (2006.01); H05K 1/11 (2006.01)

CPC H05K 1/0296 (2013.01) [H05K 1/115 (2013.01)]

15 Claims

1. A circuit board comprising:

an insulating layer;

a circuit pattern disposed on an upper surface or under a lower surface of the insulating layer; and

a buffer layer disposed on at least one of on the upper surface and under the lower surface of the insulating layer,

wherein the buffer layer includes carbon element, nitrogen element and oxygen element,

wherein a ratio of the nitrogen element to the carbon element ((carbon element/nitrogen element)*100) is 5 to 15,

wherein a ratio of the oxygen element to the carbon element ((carbon element/oxygen element)*100) is 15 to 30,

wherein the buffer layer includes a functional group which is coordinate bond with at least one of the insulating layer and the circuit pattern.