Semiconductor device and method of dissipating heat from thin package-on-package mounted to substrate

Abstract

A semiconductor device has a first substrate with a central region. A plurality of bumps is formed around a periphery of the central region of the first substrate. A first semiconductor die is mounted to the central region of the first substrate. A second semiconductor die is mounted to the first semiconductor die over the central region of the first substrate. A height of the first and second die is less than or equal to a height of the bumps. A second substrate has a thermal conduction channel. A surface of the second semiconductor die opposite the first die is mounted to the thermal conductive channel of the second substrate. A thermal interface layer is formed over the surface of the second die. The bumps are electrically connected to contact pads on the second substrate. A conductive plane is formed over a surface of the second substrate.

What is claimed: 
     
       1. A method of making a semiconductor device, comprising:
 providing a first substrate having a central region; 
 forming first bumps around a periphery of the central region of the first substrate; 
 mounting a first semiconductor die to the central region of the first substrate; 
 mounting an active surface of the second semiconductor die to the first semiconductor die over the central region of the first substrate, wherein a height of the first and second semiconductor die is less than or equal to a height of the first bumps; 
 providing a second substrate having thermal conduction channels and a conductive plane, the thermal conduction channels disposed entirely within a central region of the second substrate, the thermal conduction channels including a horizontal channel disposed on a first surface of the second substrate and vertical channels disposed through the second substrate to contact the horizontal channel and the conductive plane, the conductive plane disposed on a second surface of the second substrate and spanning across a width of the central region of the second substrate; 
 mounting a back surface of the second semiconductor die that is opposite the active surface of the second semiconductor die to the horizontal channel of the second substrate with a thermal interface material; 
 electrically connecting first contact pads disposed on the first substrate to second contact pads disposed on an active surface of the second semiconductor die using second bumps disposed between the first contact pads and second contact pads; and 
 electrically connecting the first bumps to third contact pads disposed outside the central region and on the first surface of the second substrate. 
 
     
     
       2. A method of making a semiconductor device, comprising:
 providing a first substrate; 
 mounting a first semiconductor die to the first substrate; 
 mounting an active surface of a second semiconductor die to the first semiconductor die over the first substrate; 
 forming bumps over the first substrate around a periphery of the first and second semiconductor die, wherein a height of the first and second semiconductor die is less than or equal to a height of the bumps; 
 providing a second substrate having thermal conduction channels disposed in a central region of the second substrate and a conductive plane, the thermal conduction channels including a horizontal channel disposed on a first surface of the second substrate and vertical channels disposed through the second substrate to contact the horizontal channel and the conductive plane, the conductive plane disposed on a second surface of the second substrate and spanning across a width of the central region of the second substrate; and 
 mounting a back surface of the second semiconductor die opposite the active surface of the second semiconductor die to the horizontal channel of the second substrate with a thermal interface material. 
 
     
     
       3. A method of making a semiconductor device, comprising:
 providing a first substrate; 
 mounting a first semiconductor die to the first substrate; 
 forming bumps over the first substrate around a periphery of the first semiconductor die, wherein a height of the first semiconductor die is less than or equal to a height of the bumps; 
 providing a second substrate having thermal conduction channels disposed in a central region of the second substrate and a conductive plane, the thermal conduction channels including a horizontal channel disposed entirely in the central region on a first surface of the second substrate and vertical channels disposed through the second substrate to contact the horizontal channel and the conductive plane, the conductive plane disposed on a second surface of the second substrate and spanning across an entire width of the horizontal channel; and 
 mounting a surface of the first semiconductor die to the horizontal channel of the second substrate with a thermal interface material. 
 
     
     
       4. A method of making a semiconductor device, comprising:
 providing a first substrate; 
 mounting a first semiconductor die to the first substrate; 
 forming first bumps over the first substrate around a periphery of the first semiconductor die, wherein a height of the first semiconductor die is less than or equal to a height of the first bumps; 
 providing a second substrate having thermal conduction channels, the thermal conduction channels including a horizontal channel disposed on a first surface of the second substrate and vertical channels disposed through the second substrate to contact the horizontal channel; and 
 mounting a back surface of the first semiconductor die to the horizontal channel of the second substrate with a thermal interface material, the back surface of the first semiconductor die opposite an active surface of the first semiconductor die. 
 
     
     
       5. A method of making a semiconductor device, comprising:
 providing a first substrate; 
 mounting a first semiconductor die to the first substrate; 
 forming first bumps over the first substrate around a periphery of the first semiconductor die, wherein a height of the first semiconductor die is less than or equal to a height of the first bumps; 
 providing a second substrate having thermal conduction channels, the thermal conduction channels including a horizontal channel disposed on a first surface of the second substrate and vertical channels disposed through the second substrate to contact the horizontal channel, wherein providing the second substrate comprises providing first contact pads on the first surface of the second substrate that are separated from the horizontal channel; and 
 mounting a surface of the first semiconductor die to the horizontal channel of the second substrate with a thermal interface material. 
 
     
     
       6. A method of making a semiconductor device, comprising:
 providing a first substrate; 
 mounting a first semiconductor die to the first substrate; 
 forming bumps over the first substrate and around the first semiconductor die; 
 providing a second substrate having thermal conduction channels and first contact pads disposed on a first surface of the second substrate, the thermal conduction channels including a horizontal channel disposed on the first surface of the second substrate and vertical channels disposed through the second substrate to contact the horizontal channel, the first contact pads separated from the horizontal channel; and 
 mounting a surface of the first semiconductor die to the horizontal channel of the second substrate. 
 
     
     
       7. The method of  claim 1 , wherein the second semiconductor die has a larger footprint than the first semiconductor die. 
     
     
       8. The method of  claim 1 , further including forming a plurality of conductive vias through the first semiconductor die. 
     
     
       9. The method of  claim 1 , further including depositing an underfill material between the first substrate and first and second semiconductor die. 
     
     
       10. The method of  claim 1 , further including forming a masking layer over the first substrate. 
     
     
       11. The method of  claim 2 , wherein the thermal interface material includes solder paste, heat-conductive polymer material, or b-stage adhesive. 
     
     
       12. The method of  claim 2 , further including electrically connecting the bumps to contact pads on the second substrate. 
     
     
       13. The method of  claim 2 , further including forming a plurality of conductive vias through the first semiconductor die. 
     
     
       14. The method of  claim 2 , further including:
 forming a masking layer over the first substrate; and 
 depositing an underfill material between the first substrate and first and second semiconductor die, the underfill material being contained by the masking layer. 
 
     
     
       15. The method of  claim 2 , wherein the second semiconductor die has a larger footprint than the first semiconductor die. 
     
     
       16. The method of  claim 3 , further including mounting a second semiconductor die to the first semiconductor die. 
     
     
       17. The method of  claim 3 , further including electrically connecting the bumps to contact pads on the second substrate. 
     
     
       18. The method of  claim 3 , further including depositing an underfill material between the first substrate and first semiconductor die. 
     
     
       19. The method of  claim 16 , wherein the second semiconductor die has a larger footprint than the first semiconductor die. 
     
     
       20. The method of  claim 4 , wherein mounting the back surface of the first semiconductor die to the horizontal channel comprises mounting the back surface of the first semiconductor die to the horizontal channel such that an entirety of the thermal conduction channels is disposed directly beneath the first semiconductor die. 
     
     
       21. The method of  claim 4 , wherein providing the second substrate comprises providing first contact pads on the first surface of the second substrate that are separated from the horizontal channel 
     
     
       22. The method of  claim 21 , further comprising contacting the first bumps to the first contact pads. 
     
     
       23. The method of  claim 22 , further comprising electrically connecting second contact pads disposed on an active surface of the first semiconductor die with third contact pads disposed on the first substrate using second bumps. 
     
     
       24. The method of  claim 5 , further comprising contacting the first bumps to the first contact pads. 
     
     
       25. The method of  claim 5 , wherein mounting the surface of the first semiconductor die to the horizontal channel of the second substrate comprises mounting a back surface of the first semiconductor die to the horizontal channel of the second substrate, the back surface of the first semiconductor die opposite an active surface of the first semiconductor die. 
     
     
       26. The method of  claim 24 , further comprising electrically connecting second contact pads disposed on an active surface of the first semiconductor die with third contact pads disposed on the first substrate using second bumps. 
     
     
       27. The method of  claim 25 , wherein mounting the back surface of the first semiconductor die to the horizontal channel comprises mounting the back surface of the first semiconductor die to the horizontal channel such that an entirety of the thermal conduction channels is disposed directly beneath the first semiconductor die. 
     
     
       28. The method of  claim 6 , wherein a height of the first semiconductor die is less than or equal to a height of the bumps. 
     
     
       29. The method of  claim 6 , wherein providing the second substrate includes providing a conductive plane on a second surface of the second substrate that is opposite the first surface of the second substrate. 
     
     
       30. The method of  claim 6 , wherein mounting the surface of the first semiconductor die to the horizontal channel includes mounting with a thermal interface material. 
     
     
       31. The method of  claim 6 , wherein an entirety of the vertical channels is disposed directly beneath the horizontal channel. 
     
     
       32. The method of  claim 29 , wherein a width of the conductive plane is greater than a width of the horizontal channel. 
     
     
       33. The method of  claim 32 , wherein the horizontal channel is disposed directly over a center of the substrate.