Packaging for fingerprint sensors and methods of manufacture
View Patent ↗A fingerprint sensor package, including a sensing side for sensing fingerprint information and a separate connection side for electrically connecting the fingerprint sensor package to a host device, is disclosed. The fingerprint sensor package can also include a sensor integrated circuit facing the sensing side and substantially surrounded by a fill material. The fill material includes vias at peripheral locations around the sensor integrated circuit. The fingerprint sensor package can further include a redistribution layer on the sensing side which redistributes connections of the sensor integrated circuit to the vias. The connections can further be directed through the vias to a ball grid array on the connection side. Some aspects also include electrostatic discharge traces positioned at least partially around a perimeter of the connection side. Methods of manufacturing are also disclosed.
1. A biometric object sensor wafer level fan out package, comprising:
a sensor control integrated circuit;
a molded fill material formed to at least partially encapsulate the sensor control integrated circuit;
a sensing side redistribution layer disposed on a sensing side of the package, wherein the sensing side redistribution layer comprises at least one passivation layer and a metal layer, wherein the metal layer of the sensing side redistribution layer further comprises metal redistribution traces and a metal sensor array in the sensing side redistribution layer, the metal sensor array further including a plurality of capacitively coupled drivers and pick-ups configured to detect ridges and valleys of a fingerprint;
a connection side redistribution layer disposed on a connection side of the package, wherein the connection side of the package is on an opposite side of the package relative to the sensing side;
at least one ball grid array electrical connector mounted on the connection side redistribution layer; and
a protective coating on the sensing side of the package disposed on the sensing side redistribution layer.
2. The package of claim 1 , wherein the molded fill material completely encapsulates the sensor control integrated circuit.
3. The package of claim 1 , wherein the at least one ball grid array electrical connector is connected to the sensing side of the package through a through mold via.
4. The package of claim 1 , further comprising:
a printed circuit board disposed on the connection side of the package between the at least one ball grid array electrical connector and the sensor control integrated circuit.
5. The package of claim 1 , wherein the molded fill material is formed in an opening of a printed circuit board containing the sensor control integrated circuit.
6. The package of claim 1 , wherein the package is a fingerprint sensor package.
7. The package of claim 1 , further comprising:
an interposer board disposed between the sensing side redistribution layer and the connection side redistribution layer.
8. The package of claim 1 , wherein the connection side redistribution layer comprises a multilayer printed circuit board.
9. The package of claim 1 , wherein the at least one passivation layer comprises a first passivation layer disposed between the sensor control integrated circuit and the metal layer.
10. The package of claim 9 , wherein the at least one passivation layer further comprises second passivation layer, wherein the metal layer is disposed between the first passivation layer and the second passivation layer.
11. The package of claim 1 , further comprising:
a secondary integrated circuit formed within the molded fill material along with the sensor control integrated circuit.
12. The package of claim 11 , wherein the secondary integrated circuit includes a light emitting diode.