Micro-roughened electrodeposited copper foil and copper foil substrate
A micro-roughened electrodeposited copper foil and a copper foil substrate are provided. The micro-roughened electrodeposited copper foil includes a micro-rough surface. The micro-rough surface has a plurality of peaks, a plurality of grooves and a plurality of micro-crystal clusters. Each of the grooves has a U-shaped or V-shaped cross-section profile, and the grooves have an average maximum width between 0.1 μm and 4 μm and an average depth less than or equal to 1.5 μm. Each of the micro-crystal clusters is composed of a plurality of micro-crystals each having an average diameter less than or equal to 0.5 μm grouped together. The micro-rough surface of the micro-roughened electrodeposited copper foil has an Rlr value less than 1.3. The micro-rough surface has good bonding strength relative to a substrate, and the copper foil substrate has good insertion loss performance to significantly reduce signal loss.
1. A micro-roughened electrodeposited copper foil comprising a micro-rough surface that has a plurality of peaks, a plurality of grooves and a plurality of micro-crystal clusters, wherein each of the grooves has a U-shaped or V-shaped cross-section profile, and the grooves have an average maximum width between 0.1 μm and 4 μm and an average depth less than or equal to 1.5 μm, and the micro-crystal clusters are correspondingly located on the tops of the peaks and are each composed of a plurality of micro-crystals each having an average diameter less than or equal to 0.5 μm grouped together;
wherein the micro-rough surface of the micro-roughened electrodeposited copper foil has an Rlr value less than 1.3, and the Rlr value satisfies the equation of Rlr=Rlo/L, where Rlo represents a measured profile length and L represents a measured distance.
2. The micro-roughened electrodeposited copper foil according to claim 1 , wherein each of the micro-crystals has an average height less than or equal to 2 μm.
3. The micro-roughened electrodeposited copper foil according to claim 2 , wherein each of the micro-crystal clusters has an average number of the micro-crystals being less than 15 that are stacked in a height direction of the micro-crystal clusters, and the average maximum width of the micro-crystal clusters is less than or equal to 5 μm, and a number of the micro-crystal clusters form into a branch-shaped crystal group.
4. The micro-roughened electrodeposited copper foil according to claim 1 , wherein the Rlr value the micro-rough surface of the micro-roughened electrodeposited copper foil is less than 1.26.
5. The micro-roughened electrodeposited copper foil according to claim 2 , wherein the Rlr value of the micro-rough surface of the micro-roughened electrodeposited copper foil is less than 1.26.
6. The micro-roughened electrodeposited copper foil according to claim 3 , wherein the Rlr value of the micro-rough surface of the micro-roughened electrodeposited copper foil is less than 1.26.
7. A copper foil substrate, comprising:
a substrate; and
a micro-roughened electrodeposited copper foil including a micro-rough surface attached to the substrate, the micro-rough surface having a plurality of peaks, a plurality of grooves and a plurality of micro-crystal clusters, wherein each of the grooves has a U-shaped or V-shaped cross-section profile, and the grooves have an average maximum width between 0.1 μm and 4 μm and an average depth less than or equal to 1.5 μm, and the micro-crystal clusters are correspondingly located on the tops of the peaks and each has an average height less than or equal to 2 μm;
wherein the copper foil substrate has an insertion loss between 0 and -1.5 dB/in at 20 GHz;
wherein the micro-roughened electrodeposited copper foil has a peel strength greater than 4.3 lb/in relative to the substrate.
8. The copper foil substrate according to claim 7 , wherein the copper foil substrate has an insertion loss between 0 and -1.2 dB/in at 16 GHz.
9. The copper foil substrate according to claim 8 , wherein the copper foil substrate has an insertion loss between 0 and -0.65 dB/in at 8 GHz and an insertion loss between 0 and -1.0 dB/in at 12.89 GHz.
10. The copper foil substrate according to claim 9 , wherein the insertion loss of the copper foil substrate at 8 GHz is between 0 and -0.63 dB/in, the insertion loss of the copper foil substrate at 12.89 GHz is between 0 and -0.97 dB/in, the insertion loss of the copper foil substrate at 16 GHz is between 0 and -1.15 dB/in, and the insertion loss of the copper foil substrate at 20 GHz is between 0 and -1.45 dB/in.
11. The copper foil substrate according to claim 7 , wherein the average maximum width of the micro-crystal clusters is less than or equal to 5 μm, a number of the micro-crystal clusters form into a branch-shaped crystal group, and each of the micro-crystal clusters is composed of a plurality of micro-crystals grouped together and having an average height of less than or equal to 1.8 μm, and wherein the micro-rough surface of the micro-roughened electrodeposited copper foil has an Rlr value less than 1.26, and the Rlr value satisfies the equation of Rlr=Rlo/L, where Rlo represents a measured profile length and L represents a measured distance.
12. The copper foil substrate according to claim 7 , wherein the substrate has a dielectric constant (Dk) less than 4.0 and a dissipation factor (Df) less than 0.015 at 10 GHz.