Patent ID: 9472520
Filing Date: 2016-10-18
CPC Classification: H01L,Y10T

Claim Text:
1. A method of forming a copper interconnect pillar, the method comprising: forming a first copper layer on at least one other layer; forming a first nickel barrier protective layer on the first copper layer and in direct contact with the first copper layer; forming a substantially planar first intermediate layer on the first nickel barrier protective layer, the first intermediate layer having a first surface in direct contact with the first nickel barrier protective barrier layer, and having a modulus of elasticity lower than the first copper layer; forming a second nickel barrier protective layer on a second surface of the first intermediate layer opposing the first surface of the first intermediate layer and in direct contact with the second surface of the first intermediate layer; and forming a second copper layer on the second nickel barrier protective layer and in direct contact with a surface of the second nickel barrier layer opposing the first intermediate layer, the first intermediate layer having a modulus of elasticity lower than the second copper layer.