Electronic device and method of manufacturing thereof
View Patent ↗The device has a carrier and an electric element. The carrier has a first and an opposed side and is provided with an connection layer, an intermediate layer and contact pads. The element is present at the first side and coupled to the connection layer. It is at least partially encapsulated by an encapsulation that extends into isolation areas between patterns in the intermediate layer. A protective layer is present at the second side of the carrier, which covers an interface between the contact pads and the intermediate layer.
1. A method of manufacturing an electronic device provided with an electric element and a carrier with a first side and an opposed second side, comprising:
providing the carrier comprising a patterned connection layer, an intermediate layer and a continuous carrier layer of electrically conductive material, the connection layer is present at the first side of the carrier, said intermediate layer comprising an electrically conductive material and having a pattern substantially corresponding to that of the connection layer;
mounting the electric element to the carrier;
applying an electrically insulating material which extends to a surface of the intermediate layer;
patterning the carrier layer from the second side of the carrier, therewith creating contact pads for external contacting, the contact pads are connected to corresponding patterns in the connection layer through interconnects in the intermediate layer, and
providing a protective layer at the second side of the carrier, the protective layer in contact with and covering an interface between the intermediate layer and the contact pads.
2. The method as recited in claim 1 , wherein the protective layer comprises an electrically insulating material and leaves the contact pads exposed.
3. The method as recited in claim 1 ,
wherein the carrier is provided with a masking layer at its second side, the carrier layer is first patterned through the masking layer and into contact pads, and as a result of the patterning process the masking layer has a larger surface area than the corresponding contact pads,
whereafter a positive photosensitive composition is applied at the second side of the carrier, that is subsequently patterned into irradiated and non-irradiated areas in a photolithographical treatment in which the masking layer is used as a mask, the irradiated areas being washed away.
4. The method as recited in claim 1 , wherein:
the connection layer of the carrier comprises bond pads, and
the electric element is mounted at the first side of the carrier, bond pads of the element being coupled to corresponding bond pads in the connection layer.
5. The method of claim 1 , wherein the protective layer provides mechanical support that suppresses delamination of the intermediate layer and the contact pads.
6. The method of claim 1 , wherein the protective layer is provided by one of spraying, dipping, coating and vapor deposition.
7. The method of claim 1 , wherein the electronic device includes an assembly of a plurality of individual devices designed for separation into individual devices and wherein the protective layer is provided before separation of the assembly into a plurality of individual devices.
8. The method of claim 1 , wherein the step of providing the protective layer includes the steps of adhering a first material to the contact pads and adhering a second material that does not adhere to the first material to the second side of the carrier, wherein the second material forms the protective layer.
9. The method of claim 1 , wherein the step of providing the protective layer includes the steps of applying a material that covers both the contact pads and the interface between the intermediate layer and the contact pads and removing the material through the application of pressure of solder balls during a reflow processing, thereby leaving the contact pads exposed and the interface between the intermediate layer and the contact pads covered.
10. The method of claim 1 , wherein the step of providing a protective layer includes providing a layer the chemically bonds with the intermediate layer and the contact pads.