On-chip heat spreader
A three dimensional (3D) stacked chip structure with chips having on-chip heat spreader and method of forming are described. A 3D stacked chip structure comprises a first die having a first substrate with a dielectric layer formed on a front surface. One or more bonding pads and a heat spreader may be simultaneously formed in the dielectric layer. The first die is bonded with corresponding bond pads on a surface of a second die to form a stacked chip structure. Heat generated in the stacked chip structure may be diffused to the edges of the stacked chip structure through the heat spreader.
1. A device comprising:
a semiconductor substrate having at least one active device in the semiconductor substrate;
a conductive interconnect feature in a first dielectric layer on a first surface of the semiconductor substrate, the conductive interconnect feature being coupled to the at least one active device;
a second dielectric layer over the first dielectric layer;
a third dielectric layer over the second dielectric layer;
a first bonding pad in the third dielectric layer, the first bonding pad being electrically coupled to the conductive interconnect feature; and
a first heat dissipating structure on the second dielectric layer, the first heat dissipating structure being electrically isolated from the first bonding pad and comprising a first major axis extending toward to an outer edge of the first surface, wherein the first heat dissipating structure has a bottom surface coplanar with a bottom surface of the first bonding pad.
2. The device of claim 1 , wherein the first heat dissipating structure comprises a material selected from the group consisting essentially of aluminum (Al), copper (Cu), tungsten (W), cobalt (Co), gold (Au), silver (Ag), a copper-tin alloy, a gold-tin alloy, an indium-gold alloy, a lead-tin alloy, and combinations thereof.
3. The device of claim 1 further comprising:
a first through substrate via (TSV) extending through the semiconductor substrate;
a fourth dielectric layer on a second surface of the semiconductor substrate, the second surface being opposite the first surface;
a second bonding pad on the fourth dielectric layer; and
a second heat dissipating structure on the fourth dielectric layer, the second heat dissipating structure being electrically isolated from the second bonding pad and the first TSV.
4. The device of claim 3 further comprising a third bonding pad in the third dielectric layer, the second and third bonding pads being electrically coupled to the first TSV.
5. The device of claim 3 , wherein the first TSV is coupled to the at least one active device.
6. The device of claim 3 , wherein the first and second heat dissipating structures extend to an edge of the semiconductor substrate, respectively.
7. The device of claim 3 further comprising:
a second TSV extending through the semiconductor substrate;
a fourth bonding pad in the third dielectric layer, the fourth bonding pad being coupled to a first end of the second TSV; and
a fifth bonding pad on the fourth dielectric layer, the fifth bonding pad being coupled to a second end of the second TSV.
8. The device of claim 1 , wherein the first heat dissipating structure further comprises a second major axis extending toward an outer edge of the semiconductor substrate, the second major axis being perpendicular to the first major axis.
9. A semiconductor device comprising:
a first semiconductor die comprising:
a first bonding pad on a first dielectric layer on a front-side surface of the semiconductor die;
a first through-substrate via (TSV) extending through the first semiconductor die, the TSV having a first end surface coplanar with the front-side surface of the first semiconductor die; and
a first heat spreader on the first dielectric layer, the first heat spreader being insulated from the first TSV and the first bonding pad and having at least one major axis extending along the front-side surface, the first heat spreader having a bottom surface coplanar with the first end surface of the first TSV.
10. The semiconductor device of claim 9 , wherein the first semiconductor die comprises one or more active devices, the first TSV being electrically coupled to at least one of the one or more active devices.
11. The semiconductor device of claim 10 , wherein the TSV is electrically coupled to the first bonding pad.
12. The semiconductor device of claim 10 further comprising:
a second semiconductor die attached to the first semiconductor die, the second semiconductor die comprising:
a second bonding pad on a second dielectric layer on a front-side surface of the second semiconductor die, wherein the second bonding pad is electrically connected to the first bonding pad; and
a second heat spreader on the second dielectric layer, the second heat spreader being insulated from the second bonding pad and the first bonding pad, and the second heat spreader physically contacting the first heat spreader.
13. The semiconductor device of claim 12 , wherein each of the first and second heat spreaders extend to an edge of the semiconductor device.
14. The semiconductor device of claim 12 , wherein the second semiconductor die comprises a second TSV extending through the second semiconductor die, the second bonding die being coupled to the second TSV and the first bonding pad being coupled to the first TSV.
15. The semiconductor device of claim 9 , wherein the first semiconductor die comprises a third bonding pad on a third dielectric layer on a back-side surface, the third bonding pad being coupled to the first TSV.
16. The semiconductor device of claim 15 further comprising a third heat spreader on the third dielectric layer, the third heat spreader being insulated from the third bonding pad and the first TSV.
17. A method of forming a semiconductor device, the method comprising:
forming a first semiconductor die comprising:
forming a first through substrate via (TSV) through the first semiconductor die, the first TSV having a first end surface coplanar with a front-side surface of the first semiconductor die;
forming a first bonding pad on the front-side surface, the first bonding pad being electrically coupled to the first TSV; and
forming a first heat spreader on the front-side surface, the first heat spreader being insulated from the first TSV and the first bonding pad and having at least one major axis extending along the front-side surface, the first heat spreader having a bottom surface coplanar with the first end surface of the first TSV.
18. The method of claim 17 , wherein the first semiconductor die comprises one or more active devices, and wherein the first TSV is electrically coupled to at least one of the one or more active devices.
19. The method of claim 17 further comprising:
forming a second semiconductor die comprising:
forming a second bonding pad on a front-side surface of the second semiconductor die, wherein the second bonding pad is electrically connected to the first bonding pad; and
forming a second heat spreader on the front-side surface of the second semiconductor die, the second heat spreader being insulated from the second bonding pad; and
attaching the first semiconductor die to the second semiconductor die, the first and second bonding pads being electrically coupled and the first and second heat spreaders being physically coupled.
20. The method of claim 19 , wherein the forming the second semiconductor die further comprises:
forming a second TSV extending through the second semiconductor die, the second bonding pad being electrically coupled to the second TSV.