Package substrate and package structure using the same

Abstract

A package substrate is provided. The package substrate includes a base layer having a first surface and a second surface opposite to the first surface, a plurality of through holes penetrating the base layer, a first metal layer disposed on the first surface, and comprising an encircling portion and a plurality of upper pads arranged separately, wherein the encircling portion surrounds the upper pads to form a trench between the encircling portion and the upper pads, and a second metal layer disposed on the second surface and comprising a plurality of bottom pads arranged separately, wherein the bottom pads are electrically connected to the upper pads via the through holes respectively. The through holes are positioned under the upper pads and the encircling portion of the first metal layer is electrically floating.

What is claimed is: 
     
         1 . A package substrate, comprising:
 a base layer;   a plurality of through holes penetrating through the base layer;   a first metal layer disposed on an upper surface and comprising an encircling portion and a plurality of upper pads arranged separately, wherein the encircling portion surrounds the upper pads to form a trench between the encircling portion and the upper pads, and at least one gap between the upper pads intercommunicates with the trench; and   a second metal layer disposed on the lower surface comprising a plurality of bottom pads arranged separately, wherein the bottom pads are electrically connected to the upper pads via the through holes;   wherein the encircling portion of the first metal layer is electrically floating.   
     
     
         2 . The package substrate according to  claim 1 , wherein the second metal layer further comprises:
 at least one heat dissipation pad corresponding to the upper pads and electrically insulated from the bottom pads.   
     
     
         3 . The package substrate according to  claim 2 , wherein the bottom pads of the second metal layer are divided into an anode region and a cathode region and surround the heat dissipation pad. 
     
     
         4 . The package substrate according to  claim 2 , wherein the heat dissipation pad are electrically floating. 
     
     
         5 . A package structure, comprising:
 a package substrate, comprising:   a base layer;   a plurality of through holes penetrating through the base layer;   a first metal layer disposed on an upper surface and comprising an encircling portion and a plurality of upper pads arranged separately, wherein the encircling portion surrounds the upper pads to form a trench between the encircling portion and the upper pads, and at least one gap between the upper pads intercommunicates with the trench; and   a second metal layer disposed on a lower surface comprising a plurality of bottom pads arranged separately, wherein the bottom pads are electrically connected to the upper pads via the through holes, and the encircling portion of the first metal layer is electrically floating;   at least one chip disposed on the package substrate and electrically connected to the upper pads;   a reflective layer disposed on the package substrate and having a portion filled into the trench, wherein the reflective layer covers the chip and exposes at least a portion of an upper surface of the chip; and   a light transmissive layer covering the exposed portion of the upper surface of the chip.   
     
     
         6 . The package structure according to  claim 5 , wherein the second metal layer further comprising:
 at least one heat dissipation pad corresponding to the chip and electrically insulated from the bottom pads.   
     
     
         7 . The package structure according to  claim 6 , wherein the bottom pads of the second metal layer are divided into an anode region and a cathode region and surround the heat dissipation pad. 
     
     
         8 . The package structure according to  claim 6 , wherein the heat dissipation pad is electrically floating. 
     
     
         9 . The package structure according to  claim 5 , wherein the light transmissive layer comprises a wavelength conversion layer. 
     
     
         10 . The package substrate according to  claim 5 , wherein the reflective layer extends not beyond an outer wall of the trench. 
     
     
         11 . The package structure according to  claim 5 , wherein the package substrate further comprises:
 a plating layer formed on at least one of the first metal layer and the second metal layer, wherein the plating layer is formed of gold or silver.   
     
     
         12 . A package structure, comprising:
 a package substrate, comprising:   a base layer;   a plurality of through holes penetrating through the base layer;   a first metal layer disposed on an upper surface and comprising an encircling portion and a plurality of upper pads arranged separately, wherein the encircling portion surrounds the upper pads to form a trench between the encircling portion and the upper pads, and at least one gap between the upper pads intercommunicates with the trench; and   a second metal layer disposed on a lower surface comprising a plurality of bottom pads arranged separately, wherein the bottom pads are electrically connected to the upper pads via the through holes, and the encircling portion of the first metal layer is electrically floating;   at least one chip disposed on the package substrate and electrically connected to the upper pads;   a reflective layer disposed on the package substrate and having a portion filled into the trench, wherein the reflective layer surrounds a lateral surface of the chip and exposes at least a portion of an upper surface of the chip; and   a light transmissive layer covering the exposed portion of the upper surface of the chip and at least extending between the reflective layer and the lateral surface of the chip.   
     
     
         13 . The package structure according to  claim 12 , wherein the second metal layer further comprising:
 at least one heat dissipation pad corresponding to the chip and electrically insulated from the bottom pads.   
     
     
         14 . The package structure according to  claim 13 , wherein the bottom pads of the second metal layer are divided into an anode region and a cathode region and surround the heat dissipation pad. 
     
     
         15 . The package structure according to  claim 13 , wherein the heat dissipation pad is electrically floating. 
     
     
         16 . The package structure according to  claim 12 , wherein the light transmissive layer comprises a wavelength conversion layer. 
     
     
         17 . The package substrate according to  claim 12 , wherein the reflective layer extends not beyond an outer wall of the trench. 
     
     
         18 . The package structure according to  claim 12 , wherein the package substrate further comprises:
 a plating layer formed on at least one of the first metal layer and the second metal layer; wherein the plating layer is formed of gold or silver.