Package structure with a retarding structure and method of making same
An encapsulant easily flows into a space between a substrate and an electronic device and contacts with an active region of the electronic device to affect the characteristic of the electronic device in the conventional arts. The present invention provides a package structure with a retarding structure to efficiently avoid the problem. The package structure comprises an electronic device, a substrate, a retarding structure, and an encapsulant. The substrate has conductive contacts disposed on an upper surface. The electronic device has an active region and conductive pads disposed on a first surface. The electronic device is electrically coupled to the substrate by conductive bumps between the conductive contacts and the corresponding conductive pads. The encapsulant is formed around a periphery of the electronic device. The retarding structure is disposed outside the active region on the first surface of the electronic device for avoiding the encapsulant contacting the active region of the electronic device.
1. A package structure with a retarding structure, comprising:
a substrate having conductive contacts disposed on an upper surface thereof;
an electronic device having an active region and conductive pads disposed on a first surface thereof, wherein said electronic device is electrically coupled to said substrate by conductive bumps between said conductive contacts and corresponding said conductive pads;
an encapsulant formed around a periphery of said electronic device; and
a trench formed around said active region on said first surface of said electronic device for avoiding said encapsulant contacting said active region of said electronic device.
2. The package structure in claim 1 , wherein a width of said trench is wider than 150 μm.
3. The package structure in claim 1 , wherein a depth of said trench is deeper than 150 μm.
4. The package structure in claim 1 , wherein said trench is formed by photolithography.
5. The package structure in claim 1 , wherein said trench is formed by sand-blasting.
6. The package structure in claim 1 , wherein said trench is formed by etching process.
7. The package structure in claim 1 , wherein said encapsulant is a thixotropic fluid.
8. The package structure in claim 1 , wherein said encapsulant comprises an unconductive aluminum compound.