Twinned copper layer, substrate having the same and method for preparing the same

Abstract

A twinned copper layer is disclosed, wherein 35% or more in volume of the twinned copper layer comprises plural twinned grains, 30% or more of the twinned grains are flake twinned grains, and a ratio of a length to a thickness of at least a part of the flake twinned grains is greater than or equal to 2. In addition, a substrate having the aforesaid twinned copper layer and a method for preparing the aforesaid twinned copper layer are also disclosed.

What is claimed is: 
     
         1 . A twinned copper layer, wherein 35% or more in volume of the twinned copper layer comprises plural twinned grains, 30% or more of the plural twinned grains are flake twinned grains, and a ratio of a length to a thickness of at least a part of the flake twinned grains is greater than or equal to 2. 
     
     
         2 . The twinned copper layer of  claim 1 , wherein a thickness direction of the flake twinned grains is a twin direction of the flake twinned grains. 
     
     
         3 . The twinned copper layer of  claim 1 , wherein an included angle between a twin boundary of at least a part of the plural twinned grains and a thickness direction of the twinned copper layer is ranged from 0 degree to 30 degrees. 
     
     
         4 . The twinned copper layer of  claim 1 , including:
 0.05 at % to 20 at % of at least one element selected from the group consisting of Ag, Ni, Zn, Pb, Al, Au, Pt, Mg and Cd; and   rest of Cu.   
     
     
         5 . The twinned copper layer of  claim 4 , wherein the at least one element is Ag. 
     
     
         6 . The twinned copper layer of  claim 1 , wherein a length of the at least a part of the flake twinned grains is ranged from 0.5 μm to 20 μm. 
     
     
         7 . The twinned copper layer of  claim 1 , wherein two adjacent twinned grains of the plural twinned grains are intersected. 
     
     
         8 . The twinned copper layer of  claim 1 , wherein the plural twinned grains are formed by staking plural twins along a [111] crystal axis. 
     
     
         9 . A substrate having a twinned copper layer, comprising:
 a substrate; and   a twinned copper layer disposed on the substrate or embedded into the substrate, wherein 35% or more in volume of the twinned copper layer comprises plural twinned grains, 30% or more of the plural twinned grains are flake twinned grains, and a ratio of a length to a thickness of at least a part of the flake twinned grains is greater than or equal to 2.   
     
     
         10 . The substrate of  claim 9 , wherein an included angle between a twin boundary of at least a part of the plural twinned grains and a surface of the substrate is ranged from 60 degrees to 90 degrees. 
     
     
         11 . A method for preparing a twinned copper layer, comprising the following steps:
 providing an electrodeposition device, comprising an anode, a cathode, a plating solution and a power supply, wherein the power supply is respectively connected to the cathode and the anode, and the cathode and the anode are immersed into the plating solution; and   performing an electrodeposition process with the electrodeposition device to grow a twinned copper layer on a surface of the cathode,   wherein 35% or more in volume of the twinned copper layer comprises plural twinned grains, 30% or more of the plural twinned grains are flake twinned grains, and a ratio of a length to a thickness of at least a part of the flake twinned grains is greater than or equal to 2; and   wherein the plating solution comprises a copper salt and an acid, and the plating solution does not comprise a chloride ion.   
     
     
         12 . The method of  claim 11 , wherein a thickness direction of the flake twinned grains is a twin direction of the flake twinned grains. 
     
     
         13 . The method of  claim 11 , wherein an included angle between a twin boundary of at least a part of the plural twinned grains and a thickness direction of the twinned copper layer is ranged from 0 degree to 30 degrees. 
     
     
         14 . The method of  claim 11 , wherein the twinned copper layer includes:
 0.05 at % to 20 at % of at least one element selected from the group consisting of Ag, Ni, Zn, Pb, Al, Au, Pt, Mg and Cd; and   rest of Cu.   
     
     
         15 . The method of  claim 14 , wherein plating solution further comprises a salt of the at least one element. 
     
     
         16 . The method of  claim 14 , wherein the at least one element is Ag. 
     
     
         17 . The method of  claim 16 , wherein the plating solution comprises a silver salt. 
     
     
         18 . The method of  claim 11 , wherein a length of the at least a part of the flake twinned grains is ranged from 0.5 μm to 20 μm. 
     
     
         19 . The method of  claim 11 , wherein two adjacent twinned grains of the plural twinned grains are intersected. 
     
     
         20 . The method of  claim 11 , wherein the plural twinned grains are formed by staking plural twins along a [111] crystal axis.