Packaged semiconductor device having a shielding against electromagnetic interference and manufacturing process thereof
A packaged device has a die of semiconductor material bonded to a support. An electromagnetic shielding structure surrounds the die and is formed by a grid structure of conductive material extending into the support and an electromagnetic shield, coupled together. A packaging mass embeds both the die and the electromagnetic shield. The electromagnetic shield is formed by a plurality of metal ribbon sections overlying the die and embedded in the packaging mass. Each metal ribbon section has a thickness-to-width ratio between approximately 1:2 and approximately 1:50.
1. A device comprising:
a support that includes a recess delimited by a base portion and first and second sidewalls;
an interference shield that includes:
a conductive grid having a base in the base portion of the support, the base being exposed at a surface of the support, the conductive grid including a first vertical region in the first sidewall and a second vertical region in the second sidewall, the first and second vertical regions being coupled to the base; and
a ribbon section coupled to the first vertical region at a first end and coupled to the second vertical region at a second end, the ribbon section having a curvature such that a length of the ribbon section is greater than a length of the surface of the conductive grid at the surface of the support, wherein the ribbon section and the conductive grid form an electromagnetic shield; and
a semiconductor die located in the recess and enclosed by the interference shield, wherein the semiconductor die is between the base and the ribbon section, and wherein a portion of the semiconductor die is between the first vertical region and the second vertical region.
2. The device of claim 1 wherein the curvature of the ribbon section extends from the first end to the second end.
3. The device of claim 1 wherein the ribbon section includes a first portion including the first end, a second portion including the second end, and a third portion between the first portion and the second portion, the first and second portions having curvatures and the third portion being planar.
4. The device of claim 1 wherein the ribbon section has a concave side and a convex side, the concave side being closer to the semiconductor die than the convex side.
5. The device of claim 1 wherein the ribbon section includes a first shielding ribbon and a second shielding ribbon.
6. The device of claim 5 wherein the first and second shielding ribbons are spaced apart from and parallel to each other.
7. The device of claim 1 wherein the base is a copper mesh.
8. The device of claim 1 , further comprising:
a contact region in the base portion of the support, the semiconductor die electrically coupled to the contact region.
9. The device of claim 1 wherein the support is a printed-circuit board.
10. A method, comprising:
forming a support that includes a recess and a conductive grid around the recess, a surface of the conductive grid being exposed at a surface of the support;
positioning a first semiconductor die in the recess; and
providing a shielding ribbon, wherein the shielding ribbon is coupled to the conductive grid, the shielding ribbon having a length this is greater than a length of the surface of the conductive grid at the surface of the support, the shielding ribbon and the conductive grid forming an electromagnetic shield.
11. The method of claim 10 wherein providing the shielding ribbon includes cutting a reel of ribbon to form ribbon sections and bonding the ribbon sections to the conductive grid.
12. The method of claim 11 wherein bonding the ribbon sections includes applying a bonding force to ends of the ribbon sections via a punch with ultrasound.
13. The method of claim 10 , further comprising:
electrically coupling the first semiconductor die to a contact region in the support, the contact region being electrically isolated from the shielding ribbon.
14. The method of claim 10 , further comprising:
positioning a second semiconductor die on the first semiconductor die, the second semiconductor die extending from the recess of the support.
15. A device, comprising:
a support including a recess, a conductive grid in the support and around the recess, a surface of the conductive grid being exposed at a surface of the support;
a semiconductor die in the recess and coupled to the support; and
a shielding ribbon coupled to the surface of the conductive grid that is exposed at the surface of the support, the shielding ribbon having a length this is greater than a length of the surface of the conductive grid at the surface of the support, the shielding ribbon and the conductive grid forming an electromagnetic shield.
16. The device of claim 15 wherein the shielding ribbon includes a first shielding ribbon and a second shielding ribbon.
17. The device of claim 16 wherein the first and second shielding ribbons each are spaced apart from and parallel to each other, each shielding ribbon having a thickness-to-width ratio between approximately 1:2 and approximately 1:50.
18. The device of claim 15 wherein the conductive grid is a copper mesh and the support is a printed-circuit board.