Methods of manufacturing stacked semiconductor die assemblies with high efficiency thermal paths

Abstract

Method for packaging a semiconductor die assemblies. In one embodiment, a method is directed to packaging a semiconductor die assembly having a first die and a plurality of second dies arranged in a stack over the first die, wherein the first die has a peripheral region extending laterally outward from the stack of second dies. The method can comprise coupling a thermal transfer structure to the peripheral region of the first die and flowing an underfill material between the second dies. The underfill material is flowed after coupling the thermal transfer structure to the peripheral region of the first die such that the thermal transfer structure limits lateral flow of the underfill material.

I/We claim: 
     
         1 . A method for packaging a semiconductor die assembly having a first die and a plurality of second dies arranged in a stack and attached to the first die, wherein the first die has a peripheral region extending laterally outward from the stack of second dies, the method comprising:
 positioning at least a portion of a thermal transfer structure at the peripheral region of the first die, wherein the thermal transfer structure comprises a thermally conductive material; and   flowing an underfill material between the second dies after positioning the thermal transfer structure on the peripheral region of the first die, wherein the underfill material has a fillet extending laterally from the stack of second dies, and wherein the lateral extension of the underfill material is limited by the thermal transfer structure.   
     
     
         2 . The method of  claim 1  wherein the first portion of the thermal transfer structure comprises a sidewall extending to a height of an uppermost second die and the second portion of the thermal transfer member comprises a top. 
     
     
         3 . The method of  claim 1  wherein:
 the thermal transfer structure comprises a sidewall, a top integrally formed with the sidewall, a cavity formed by the sidewall and the top, and an inlet; 
 the sidewall has a foundation configured to surround at least a portion of the first die and a shoulder configured to be positioned over the peripheral region of the first die; 
 positioning the thermal transfer structure on the peripheral region of the first die comprises attaching the foundation to a package support substrate and attaching the shoulder to the peripheral region of the die, wherein the stack of second dies is in the cavity; and 
 flowing the underfill material between the second dies comprises injecting the underfill material into the cavity via the inlet. 
 
     
     
         4 . The method of  claim 3  wherein the thermal transfer structure further comprises an outlet, and wherein the inlet is a first passageway through the top and the outlet is a second passageway through the top. 
     
     
         5 . The method of  claim 3  wherein the thermal transfer structure further comprises an outlet, and wherein the inlet and the outlet are laterally offset from each other. 
     
     
         6 . The method of  claim 3  wherein the underfill material contacts sides of the second dies. 
     
     
         7 . A method for packaging a semiconductor die assembly having a first die and a plurality of second dies arranged in a stack over the first die, wherein the first die has a peripheral region extending laterally outward from the stack of second dies, the method comprising:
 coupling a thermal transfer structure to the peripheral region of the first die; and   flowing an underfill material between the second dies after coupling the thermal transfer structure to the peripheral region of the first die, and wherein the thermal transfer structure limits lateral flow of the underfill material.   
     
     
         8 . The method of  claim 7  wherein:
 the thermal transfer structure comprises a metal casing having a sidewall and a top; 
 coupling the thermal transfer structure to the peripheral region of the first die comprises attaching a lower portion of the sidewall to the peripheral region of the first die and attaching the top to an uppermost second die of the stack of second dies; and 
 flowing the underfill material comprises instilling the underfill material between at least the sidewall of the casing and the stack of second dies. 
 
     
     
         9 . The method of  claim 7  wherein:
 the thermal transfer structure comprises a metal casing having a sidewall, a top integrally formed with the sidewall, and an inlet, and the sidewall further comprises a foundation configured to extend at least around a portion of the first die and a shoulder configured to be positioned over the peripheral region of the first die; 
 coupling the thermal transfer structure to the peripheral region of the first die comprises attaching the foundation to a package support substrate and attaching the shoulder to the peripheral region of the first die, wherein a thermal interface material is between the shoulder and the peripheral region of the first die; and 
 flowing the underfill material comprises injecting the underfill material into the casing through the inlet. 
 
     
     
         10 . The method of  claim 9  wherein the casing further comprises an outlet, and the method further comprises exhausting matter from the casing via the exhaust port and plugging the outlet. 
     
     
         11 . The method of  claim 10 , wherein the inlet and the outlet extend through the sidewall at substantially the same elevation. 
     
     
         12 . The method of  claim 10 , wherein the inlet and the outlet extend through the sidewall at different elevations. 
     
     
         13 . The method of  claim 7  wherein:
 the thermal transfer structure comprises a metal casing having the base and a separate cover, and wherein the base further comprises a foundation configured to extend at least around a portion of the first die and a shoulder configured to be positioned over the peripheral region of the first die; 
 coupling the thermal transfer structure to the peripheral region of the first die comprises attaching the foundation of the base to a package support substrate and attaching the shoulder of the base to the peripheral region of the first die, wherein a thermal interface material is between the shoulder of the base and the peripheral region of the first die; and 
 flowing the underfill material comprises depositing the underfill material such that it flows between the base and the stack of second dies. 
 
     
     
         14 . The method of  claim 7  wherein:
 the thermal transfer structure comprises a casing having a sidewall and a top; 
 the sidewall includes an inlet and an outlet extending therethrough; 
 the inlet and the outlet extend through the sidewall at substantially the same elevation; and 
 flowing the underfill material comprises injecting the underfill material into the casing through the inlet. 
 
     
     
         15 . The method of  claim 7  wherein:
 the thermal transfer structure comprises a casing having a sidewall and a top; 
 the sidewall includes an inlet and an outlet extending therethrough; 
 the inlet and the outlet extend through the sidewall at different elevations; and 
 flowing the underfill material comprises injecting the underfill material into the casing through the inlet. 
 
     
     
         16 . A method for packaging a semiconductor die assembly having a first die and a plurality of second dies arranged in a stack over the first die, wherein the first die has a peripheral region extending laterally outward from the stack of second dies, the method comprising:
 coupling at least a portion of a thermal transfer structure to a package support substrate such that the first die and the second dies are within a cavity of the thermal transfer structure; and   instilling a dielectric liquid in the cavity of the thermal transfer structure, and wherein the dielectric liquid has a high thermal conductivity.   
     
     
         17 . The method of  claim 16  wherein the thermal transfer structure comprises a casing having a sidewall and a top, wherein the sidewall and the top are integrally formed together. 
     
     
         18 . The method of  claim 16  wherein:
 the thermal transfer structure comprises a casing having a sidewall and a top; 
 the sidewall includes an inlet and an outlet extending therethrough; 
 the inlet and the outlet extend through the sidewall at different elevations; and 
 instilling the dielectric liquid in the cavity of the thermal transfer structure includes injecting the dielectric liquid into the cavity via the inlet. 
 
     
     
         19 . The method of  claim 16  wherein:
 the thermal transfer structure comprises a casing having a sidewall and a top; 
 the sidewall includes an inlet and an outlet extending therethrough; 
 the inlet and the outlet extend through the sidewall at substantially the same elevation; and 
 instilling the dielectric liquid in the cavity of the thermal transfer structure includes injecting the dielectric liquid into the cavity via the inlet.