Electronic circuit protection device
A device for protecting an electronic circuit comprising a support to which are attached at least two circuit portions, each comprising at least one integrated circuit chip. The device comprises a wafer of a semiconductor material covered with a conductive layer arranged parallel to the support, the wafer being connected to the support by conductive pillars distributed around each circuit portion and in contact with the conductive layer.
1. A device, comprising:
an electronic circuit that includes a support to which are attached at least two circuit portions, each including at least one integrated circuit chip;
a wafer of a semiconductor material spaced apart from the support;
a conductive layer arranged parallel to the support and covering a surface of the wafer that faces the support; and
conductive pillars connecting the wafer to the support and extending from the conductive layer to the support, the conductive pillars being distributed around each circuit portion and in contact with the conductive layer.
2. The device of claim 1 , wherein several adjacent conductive pillars are spaced apart, the device further comprising an insulating region arranged at least between the wafer and the support and covering each circuit portion.
3. The device of claim 1 , wherein the support comprises:
a planar insulating portion;
first conductive tracks arranged on a first surface of the planar insulating portion, the first conductive tracks being connected to at least some of the conductive pillars;
second conductive tracks arranged on a second surface of the planar insulating portion opposite to the first surface, the second conductive tracks being for connection to a reference voltage; and
means, contained in the planar insulating portion, for connecting the first conductive tracks to the second conductive tracks.
4. The device of claim 1 , wherein the conductive pillars have a spherical shape.
5. The device of claim 1 , wherein the conductive pillars have an at least partly cylindrical shape.
6. The device of claim 1 , wherein at least two adjacent conductive pillars are in contact.
7. The device of claim 1 , wherein the support is a ball grid array package.
8. A method for manufacturing electronic circuits, comprising the steps of:
providing a planar support;
attaching circuit portions on a surface of the support, each circuit portion containing at least one integrated circuit chip; and
attaching wafer portions of a semiconductor material to the support, the wafer portions being spaced apart from and parallel to said surface of the support, each wafer portion: covering a respective one of the circuit portions, having a side facing the circuit portions being covered with a conductive layer, and being connected to the support by conductive pillars distributed around each of said circuit portions and extending between the conductive layer and the support.
9. The method of claim 8 , wherein at least several adjacent conductive pillars are spaced apart and the delimiting step is preceded by introducing an insulating material between spaced apart portions of the conductive pillars and under each wafer portion to cover said at least two adjacent circuit portions.
10. The method of claim 8 , wherein the wafer portions are obtained by sawing of a wafer on which the conductive pillars are distributed.
11. The method of claim 8 wherein the conductive pillars are formed by spreading welding paste through a mask on to the conductive layer.
12. The method of claim 8 wherein the conductive pillars are formed by forming an insulating layer on the conductive layer, etching the insulating layer to form openings, and forming the conductive pillars in the openings.
13. A protected electronic device, comprising:
a support;
first and second circuit portions positioned on the support, each circuit portion including at least one integrated circuit chip;
a wafer spaced apart from the support;
a conductive layer arranged parallel to the support and covering a surface of the wafer that faces the support; and
conductive pillars connecting the wafer to the support and extending from the conductive layer to the support, the conductive pillars being distributed around each circuit portion and in contact with the conductive layer,
wherein the wafer is of a semiconductor material.
14. The device of claim 13 , wherein several adjacent conductive pillars are spaced apart, the device further comprising an insulating region arranged at least between the wafer and the support and covering each circuit portion.
15. The device of claim 13 , wherein the support comprises:
a planar insulating portion;
first conductive tracks arranged on a first surface of the planar insulating portion, the first conductive tracks being connected to at least some of the conductive pillars;
second conductive tracks arranged on a second surface of the planar insulating portion opposite to the first surface, the second conductive tracks being for connection to a reference voltage; and
conductive vias extending through the planar insulating portion and connecting the first conductive tracks to the second conductive tracks.
16. The device of claim 13 , wherein the conductive pillars have a spherical shape.
17. The device of claim 13 , wherein the conductive pillars have an at least partly cylindrical shape.
18. The device of claim 13 , wherein at least two adjacent conductive pillars are in contact.
19. The device of claim 13 , wherein the conductive pillars are distributed around four sides of each of the circuit portions.