Patent ID: 9548276
Date: 2017-01-17
CPC Classifications: H01L

Claim:
1. An improved structure of backside copper metallization for semiconductor devices comprising: a substrate, wherein said substrate is made of GaAs, InP, GaN or SiC; an active layer formed on a front side of said substrate, wherein said active layer includes at least one integrated circuit; a backside metal seed layer formed on a backside of said substrate, wherein said backside metal seed layer contains Pd and P; a high-temperature sustaining buffer layer formed below said backside metal seed layer, wherein said high-temperature sustaining layer is made of Ni alloys, Ni or Ag; and a backside metal layer formed below said high-temperature sustaining buffer layer, wherein said backside metal layer is made of Cu; wherein the Pd contained in said backside metal seed layer is uniformly distributed in said backside metal seed layer and the P contained in said backside metal seed layer is uniformly distributed in said backside metal seed layer; and wherein at high temperature the Pd contained in said backside metal seed layer is distributed closer to said backside of said substrate while the P contained in said backside metal seed layer is distributed closer to said high-temperature sustaining buffer layer, and thereby said high-temperature sustaining buffer layer and the P contained in said backside metal seed layer are mixed at the nearby boundary.