Heat dissipation in semiconductor devices
An integrated circuit die with two material layers having metal nano-particles and the method of forming the same are provided. The integrated circuit die includes a device layer comprising a first transistor, a first interconnect structure on a first side of the device layer, a first material layer on the first interconnect structure, wherein the first material layer comprises first metal nano-particles, and a second material layer bonded to the first material layer, wherein the second material layer comprises second metal nano-particles, and wherein the first material layer and the second material layer share an interface.
1 . A device comprising:
a device layer comprising a first transistor;
a first interconnect structure on a first side of the device layer;
a first material layer on the first interconnect structure, wherein the first material layer comprises a first base layer and first metal nano-particles, wherein the first metal nano-particles are surrounded by the first base layer, and wherein the first metal nano-particles have a higher thermal conductivity than the first base layer; and
a second material layer bonded to the first material layer, wherein the second material layer comprises a second base layer and second metal nano-particles, wherein the second metal nano-particles are surrounded by the second base layer, and wherein the first material layer and the second material layer share an interface.
2 . The device of claim 1 , wherein the first metal nano-particles are disposed in first metal nano-particle clusters of the first material layer, wherein each of the first metal nano-particle clusters comprises a plurality of the first metal nano-particles, wherein the second metal nano-particles are disposed in second metal nano-particle clusters of the second material layer, and wherein each of the second metal nano-particle clusters comprises a plurality of the second metal nano-particles.
3 . The device of claim 1 , wherein the first material layer has a first thermal conductivity in a range of 20 W/m·K to 80 W/m·K and wherein the second material layer has a second thermal conductivity in a range of 20 W/m·K to 80 W/m·K.
4 . The device of claim 1 , wherein the first base layer and the second base layer each comprises titanium oxide, nickel oxide, or zinc oxide.
5 . The device of claim 1 , wherein the first metal nano-particles comprise ruthenium nano-particles or niobium nano-particles.
6 . The device of claim 1 , wherein the first base layer comprises a crystalline metal oxide, and wherein the second base layer comprises a crystalline metal oxide.
7 . A device comprising:
a first transistor structure and a second transistor structure in a device layer;
an interconnect structure on the device layer, the first transistor structure being electrically coupled to the second transistor structure through the interconnect structure;
a first bonding layer on the interconnect structure, wherein the first bonding layer comprises first metal nano-particle aggregates, and wherein each of the first metal nano-particle aggregates comprises first metal nano-particles;
a substrate; and
a second bonding layer on the substrate, wherein the second bonding layer comprises second metal nano-particle aggregates, wherein each of the second metal nano-particle aggregates comprises second metal nano-particles, wherein the first metal nano-particles and the second metal nano-particles comprise different materials, and wherein the substrate is directly bonded to the interconnect structure by the first bonding layer and the second bonding layer.
8 . The device of claim 7 , wherein the first metal nano-particles have a first thermal conductivity greater than 100 W/m·K and the second metal nano-particles have a second thermal conductivity greater than 100 W/m·K.
9 . The device of claim 7 , wherein the first metal nano-particle aggregates are embedded in a first base layer of the first bonding layer, and wherein the second metal nano-particle aggregates are embedded in a second base layer of the second bonding layer.
10 . The device of claim 9 , wherein the first base layer and the second base layer each comprises crystalline titanium oxide.
11 . A method comprising:
forming a device layer on a semiconductor substrate, the device layer comprising a transistor;
forming an interconnect structure over the device layer;
depositing a first bonding layer on the interconnect structure, wherein the first bonding layer comprises a first base layer and first metal nano-particles embedded in the first base layer, wherein the first metal nano-particles are surrounded by the first base layer, and wherein the first base layer and the first metal nano-particles comprise different materials; and
directly bonding the first bonding layer to a second bonding layer by dielectric-to-dielectric bonding, wherein the second bonding layer is on a substrate before bonding the first bonding layer to the second bonding layer, wherein the second bonding layer comprises a second base layer and second metal nano-particles embedded in the second base layer, and wherein the second metal nano-particles are surrounded by the second base layer.
12 . The method of claim 11 , wherein bonding the first bonding layer to the second bonding layer comprises annealing the first bonding layer and the second bonding layer after the first bonding layer and the second bonding layer are brought into contact.
13 . The method of claim 12 , wherein the first base layer and the second base layer are amorphous before annealing the first bonding layer and the second bonding layer.
14 . The method of claim 13 , wherein annealing the first bonding layer and the second bonding layer comprises crystallizing the first base layer and the second base layer.
15 . The method of claim 12 , wherein the first metal nano-particles and the second metal nano-particles diffuse and form aggregates during annealing the first bonding layer and the second bonding layer.
16 . The method of claim 12 , wherein bonding the first bonding layer to the second bonding layer comprises performing a surface treatment on surfaces of the first bonding layer to the second bonding layer to form hydroxyl groups on the surfaces of the first bonding layer to the second bonding layer with a plasma treatment.
17 . The method of claim 12 , wherein bonding the first bonding layer to the second bonding layer comprises performing a surface treatment on surfaces of the first bonding layer to the second bonding layer to form hydroxyl groups on the surfaces of the first bonding layer to the second bonding layer with a wet chemical treatment.
18 . The method of claim 11 , wherein the first metal nano-particles have a higher thermal conductivity than the first base layer.
19 . The method of claim 11 , wherein a concentration of the first metal nano-particles is in a range of 0.1 wt. % to 10 wt. % in the first bonding layer.
20 . The device of claim 9 , wherein the first metal nano-particle aggregates are electrically isolated from the substrate and the interconnect structure by the first base layer, and wherein the second metal nano-particle aggregates are electrically isolated from the substrate and the interconnect structure by the second base layer.