Bonding layer and process
A method includes providing a first bonding surface on a first substrate, the first bonding surface including a bonding layer that is thermally curable or photocurable. The method includes providing a second bonding surface on a second substrate. The method includes bonding the first substrate to the second substrate by making physical contact between the first bonding surface and second bonding surface. The method further includes applying thermal energy or light to the bonding layer.
1 . A method, comprising:
providing a first bonding surface on a first substrate, the first bonding surface including a bonding layer that is thermally curable or photocurable;
providing a second bonding surface on a second substrate;
bonding the first substrate to the second substrate by making physical contact between the first bonding surface and the second bonding surface; and
applying thermal energy or light to the bonding layer,
wherein applying the thermal energy or the light covalently bonds the bonding layer to the first substrate at the first bonding surface and to the second substrate at the second bonding surface, respectively.
2 . The method of claim 1 , wherein the bonding layer is a first bonding layer, wherein the second bonding surface includes a second bonding layer that is thermally curable or photocurable.
3 . The method of claim 1 , wherein applying the light includes implementing UV radiation at a wavelength of 210 nm to 260 nm.
4 . The method of claim 1 , wherein applying the thermal energy includes heating the bonding layer at a temperature of at least 250° C.
5 . The method of claim 1 , wherein the bonding layer includes a precursor molecule having a silicon-containing ring structure.
6 . The method of claim 5 , wherein the bonding layer includes disilacyclobutanes (DSCB).
7 . The method of claim 1 , wherein the first substrate includes a conductive feature disposed in a dielectric layer, and wherein providing the first bonding surface includes:
depositing a bonding layer over the first substrate; and
removing a portion of the bonding layer to expose the conductive feature such that the first bonding surface includes the conductive feature and a remaining portion of the bonding layer.
8 . The method of claim 7 , further comprising recessing a top portion of the conductive feature such that the bonding layer protrudes from the recessed conductive feature, wherein applying the thermal energy causes the recessed conductive feature to expand toward the second bonding surface.
9 . A method, comprising:
providing a first bonding surface on a first substrate, the first bonding surface including a first bonding layer that is thermally curable or photocurable;
providing a second bonding surface on a second substrate, the second bonding surface including a second bonding layer;
bonding the first substrate to the second substrate by making physical contact between the first bonding layer and the second bonding layer; and
applying thermal energy or light to the first bonding layer and the second bonding layer.
10 . The method of claim 9 , wherein the second bonding layer is thermally curable or photocurable.
11 . The method of claim 9 , wherein the first bonding layer is thermally curable, and wherein applying the thermal energy is implemented at a temperature at least 250° C.
12 . The method of claim 9 , wherein the first bonding layer is photocurable, the method further comprising performing an annealing process after applying the light.
13 . The method of claim 12 , wherein applying the light includes implementing UV radiation at a wavelength of 210 nm to 260 nm.
14 . The method of claim 9 , wherein applying the thermal energy or the light includes:
forming first covalent bonds at a first interface between the first bonding layer and the first substrate;
forming second covalent bonds at a second interface between the second bonding layer and the second substrate; and
forming third covalent bonds at a third interface between the first bonding layer and the second bonding layer.
15 . The method of claim 14 , wherein at least one of the first, the second, and the third covalent bonds include a carbosilane linkage.
16 . The method of claim 9 , wherein the first bonding layer includes a precursor molecule having a silicon-containing ring structure.
17 . The method of claim 16 , wherein the silicon-containing ring structure is coupled to an aryl group.
18 . A semiconductor structure, comprising:
a first substrate;
a second substrate; and
a bonding layer bonding the first substrate to the second substrate, the bonding layer including a polymer-based material that includes carbosilane linkages.
19 . The semiconductor structure of claim 18 , wherein the bonding layer includes disilacyclobutanes (DSCB).