Semiconductor structure and method of fabricating the same

Abstract

A semiconductor structure including a semiconductor substrate, an interconnect structure disposed over the semiconductor substrate, and a bonding structure disposed over the interconnect structure is provided. The bonding structure includes a dielectric layer covering the interconnect structure, signal transmission features penetrating through the dielectric layer, and a thermal conductive feature penetrating through the dielectric layer. The thermal conductive feature includes a thermal routing and thermal pads, and the thermal pads are disposed on and share the thermal routing.

What is claimed is: 
     
         1 . A semiconductor structure, comprising:
 a semiconductor substrate;   an interconnect structure disposed over the semiconductor substrate, the interconnect structure comprising interconnect wirings, a passivation layer covering the interconnect wirings and a first thermal conductor partially covered by the passivation layer; and   a bonding structure disposed over the interconnect structure, the bonding structure comprising a dielectric layer covering the interconnect structure, signal transmission features penetrating through the dielectric layer, and a thermal conductive feature penetrating through the dielectric layer, wherein the thermal conductive feature is in contact with the first thermal conductor.   
     
     
         2 . The semiconductor structure as claimed in  claim 1 , wherein the dielectric layer comprises a bonding dielectric layer and an inter-dielectric layer disposed between the bonding dielectric layer and the interconnect structure. 
     
     
         3 . The semiconductor structure as claimed in  claim 2 , wherein each signal transmission feature among the signal transmission features comprises a via penetrating through the inter-dielectric layer and a bonding pad penetrating through the bonding dielectric layer, and the bonding pad is electrically connected to the interconnect structure through the via. 
     
     
         4 . The semiconductor structure as claimed in  claim 2 , wherein the thermal conductive feature comprises a thermal routing and thermal pads, the thermal pads are disposed on and share the thermal routing, the thermal routing laterally extends between at least two neighboring signal transmission features among the signal transmission features, the thermal routing penetrates through the inter-dielectric layer, and the thermal pads penetrate through the bonding dielectric layer. 
     
     
         5 . The semiconductor structure as claimed in  claim 2 , wherein the bonding structure further comprises dummy pads embedded in the bonding dielectric layer, and the dummy pads are electrically insulated from the interconnect structure by the inter-dielectric layer. 
     
     
         6 . The semiconductor structure as claimed in  claim 1 , wherein the thermal conductive feature comprises a thermal routing and thermal pads, the thermal pads are disposed on and share the thermal routing, the thermal routing laterally extends between at least two neighboring signal transmission features among the signal transmission features, and the thermal routing laterally extends along a meandering path. 
     
     
         7 . The semiconductor structure as claimed in  claim 1 , wherein the thermal conductive feature comprises a thermal routing and thermal pads, the thermal pads are disposed on and share the thermal routing, the thermal routing laterally extends between at least two neighboring signal transmission features among the signal transmission features, the thermal routing comprises via portions and wall portions laterally connecting via portions, and the via portions are in contact with the thermal pads, and wherein at least one of the wall portions laterally extend between at least two neighboring signal transmission features among the signal transmission features. 
     
     
         8 . The semiconductor structure as claimed in  claim 1 , wherein the thermal conductive feature is electrically insulated from the signal transmission features. 
     
     
         9 . The semiconductor structure as claimed in  claim 1 , wherein the thermal conductive feature is electrical floating. 
     
     
         10 . The semiconductor structure as claimed in  claim 1 , wherein the thermal conductive feature comprises a thermal routing and thermal pads, the thermal pads are disposed on and share the thermal routing, the thermal routing laterally extends between at least two neighboring signal transmission features among the signal transmission features, the interconnect structure further comprises a second thermal conductor disposed over the passivation layer, and a second portion of the thermal routing is landed on the second thermal conductor. 
     
     
         11 . A semiconductor structure, comprising:
 a first semiconductor die comprising an interconnect structure and a first bonding structure, the interconnect structure comprising interconnect wirings, a passivation layer covering the interconnect wirings and a thermal conductor partially covered by the passivation layer, and the thermal routing being in contact with the thermal conductor, the first bonding structure comprising a first dielectric layer, first signal transmission features penetrating through the first dielectric layer, and a first thermal conductive feature penetrating through the first dielectric layer;   a second semiconductor die comprising a second bonding structure, the second bonding structure comprising a second dielectric layer, second signal transmission features penetrating through the second dielectric layer, and a second thermal conductive feature penetrating through the second dielectric layer; and   an insulating encapsulant disposed on the second semiconductor die and encapsulating the first semiconductor die,   wherein the first dielectric layer is bonded to the second dielectric layer, the first signal transmission features are bonded and electrically connected to the second signal transmission features, and the first thermal pads are bonded and thermally coupled to the second thermal pads.   
     
     
         12 . The semiconductor structure as claimed in  claim 11 , wherein the first thermal conductive feature comprises a first thermal routing and first thermal pads, the first thermal pads are disposed on and share the first thermal routing, and the first thermal routing laterally extends between at least two neighboring first signal transmission features among the first signal transmission features, and the first thermal routing comprises a meshed thermal routing. 
     
     
         13 . The semiconductor structure as claimed in  claim 11 , wherein the first thermal conductive feature and the second thermal conductive feature are electrical floating, and the first thermal conductive feature and the second thermal conductive feature are electrically insulated from the first signal transmission features and the second signal transmission features. 
     
     
         14 . The semiconductor structure as claimed in  claim 11 , wherein the first bonding structure further comprises first dummy pads embedded in the first dielectric layer, the second bonding structure further comprises second dummy pads embedded in the second dielectric layer, the first dummy pads and the second dummy pads are bonded. 
     
     
         15 . The semiconductor structure as claimed in  claim 11 , wherein the first thermal conductive feature comprises a first thermal routing and first thermal pads, the first thermal pads are disposed on and share the first thermal routing, and the first thermal routing laterally extends between at least two neighboring first signal transmission features among the first signal transmission features, the first thermal routing comprises first via portions and first wall portions laterally connecting first via portions, and the first via portions are in contact with the first thermal pads, and wherein at least one of the first wall portions laterally extend between at least two neighboring first signal transmission features among the first signal transmission features. 
     
     
         16 . The semiconductor structure as claimed in  claim 11 , wherein the second thermal conductive feature comprises a second thermal routing and second thermal pads, and the second thermal pads are disposed on and share the second thermal routing, the second thermal routing comprises second via portions and second wall portions laterally connecting second via portions, and the second via portions are in contact with the second thermal pads, and wherein at least one of the second wall portions laterally extend between at least two neighboring second signal transmission features among the second signal transmission features. 
     
     
         17 . A method, comprising:
 providing a semiconductor substrate having an interconnect structure disposed thereon, wherein the interconnect structure comprises interconnect wirings, a passivation layer covering the interconnect wirings and a thermal conductor partially covered by the passivation layer; and   forming an inter-dielectric layer over the interconnect structure;   forming vias and a thermal routing in the inter-dielectric layer, wherein and the thermal routing is in contact with the thermal conductor;   forming a bonding dielectric layer over the inter-dielectric layer; and   forming bonding pads and thermal pads in the bonding dielectric layer, wherein the bonding pads are formed on the vias.   
     
     
         18 . The method as claimed in  claim 17 , wherein dummy pads are in the bonding dielectric layer when forming the bonding pads and the thermal pads in the bonding dielectric layer, and the dummy pads are electrically insulated from the interconnect structure by the inter-dielectric layer. 
     
     
         19 . The method as claimed in  claim 17 , wherein the thermal routing is formed on a thermal conductor partially covered by the passivation layer of the interconnect structure. 
     
     
         20 . The method as claimed in  claim 17 , wherein the thermal routing is formed on a thermal conductor disposed over the passivation layer of the interconnect structure, and the thermal conductor is embedded in the inter-dielectric layer.