Electronic device furnished with a conducting layer and method of fabrication
An electronic device includes a support board having a mounting face and an integrated circuit chip mounted on the mounting face. An encapsulation block embeds the integrated circuit chip, the encapsulation block extending above the integrated circuit chip and around the integrated circuit chip on the mounting face of the support board. The encapsulation block includes a front face with a hole passing through the encapsulation block to uncovering at least part of an electrical contact. A layer made of an electrically conducting material fills the hole to make electrical connection to the electrical contact and further extends over the front face of the encapsulation block.
1. A method for fabricating an electronic device, comprising:
producing a hole through an encapsulation block of a primary electronic device comprising a support board and an integrated circuit chip mounted on a mounting face of the support board, said hole at least partially uncovering an electrical contact, the encapsulation block having a front face parallel to the support board;
depositing an electrically conducting liquid or pasty material on at least one zone of the front face of the encapsulation block and in the hole; and
hardening the electrically conducting liquid or pasty material so as to produce a conducting layer connected to the electrical contact.
2. The method according to claim 1 , further comprising: producing a groove in the front face of the encapsulation block, said groove emerging in the hole; wherein depositing further comprises depositing the electrically conducting liquid or pasty material in said groove.
3. The method according to claim 2 , wherein producing the groove comprises forming the groove to have a spiral shape.
4. The method according to claim 1 ,
wherein producing the hole comprises producing at least two holes through the encapsulation block of the primary electronic device so as to at least partially uncover two electrical contacts;
wherein depositing comprises depositing the electrically conducting liquid or pasty material on the at least one zone of the front face of the encapsulation block and in the two holes; and
wherein hardening comprises hardening the electrically conducting liquid or pasty material so as to produce the conducting layer that is electrically connected to said two electrical contacts.
5. The method according to claim 1 , wherein the electrically conducting liquid or pasty material is a resin containing electrical conducting metallic particles.
6. The method according to claim 1 , wherein the electrical contact is located on the mounting face of the support board at a position located remote from a periphery of the integrated circuit chip.
7. The method according to claim 1 , wherein the electrical contact is located on surface of the integrated circuit chip.
8. The method according to claim 7 , further comprising forming the integrated circuit chip with a through silicon via connected to the electrical contact.
9. The method according to claim 1 , wherein depositing comprises completely filling the hole with the electrically conducting liquid or pasty material.
10. The method according to claim 1 , wherein depositing comprises using a syringe to deposit the electrically conducting liquid or pasty material.
11. The method according to claim 10 , further comprising scraping a spatula over the front face of the encapsulation block to make an upper surface of the deposited electrically conducting liquid or pasty material coplanar with the front face of the encapsulation block.
12. The method according to claim 1 , wherein hardening comprises applying a radiation to the electrically conducting liquid or pasty material.