Semiconductor device and method of manufacture
Semiconductor devices and methods of manufacturing are presented in which a first spacer layer and a second spacer layer are formed. In embodiments the first spacer layer and the second spacer layer are formed with an enhanced etch resistance. Such an enhanced etch resistance works to help prevent undesired breakthroughs during subsequent manufacturing processes.
1 . A method of manufacturing a semiconductor device, the method comprising:
depositing a gate structure over a semiconductor substrate;
depositing a first spacer layer adjacent to the gate structure, the first spacer layer comprising SiOCN, wherein the depositing the first spacer layer comprises:
depositing a first portion of the first spacer layer;
treating the first portion of the first spacer layer;
after the treating the first portion depositing a second portion of the first spacer layer in physical contact with the first portion of the first spacer layer; and
treating the second portion of the first spacer layer;
depositing a second spacer layer in physical contact with the first spacer layer, the second spacer layer comprising SiOC; and
exposing a surface of the first spacer layer opposite the second spacer layer.
2 . The method of claim 1 , wherein the depositing the first spacer layer deposits the first spacer layer to a thickness of between about 20 Å and about 30 Å and the depositing the second spacer layer deposits the second spacer layer to a thickness of between about 29 Å and about 45 Å.
3 . The method of claim 1 , wherein the treating the first portion of the first spacer layer comprises a plasma hydrogen treatment.
4 . The method of claim 1 , wherein the first spacer layer has a silicon concentration of about 32.4%-at., a carbon concentration of about 13.5%-at., an oxygen concentration of about 49.9%-at., and a nitrogen concentration of about 4.2%-at.
5 . The method of claim 4 , wherein the first spacer layer has a K-value of about 4.7 and a density of about 2.4 g/cm 3 .
6 . The method of claim 1 , wherein the first spacer layer has a silicon concentration of about 33%-at., a carbon concentration of about 12.5%-at., an oxygen concentration of about 49.8%-at., and a nitrogen concentration of about 4.7%-at.
7 . The method of claim 1 , wherein the first spacer layer has a thickness of about 30 Å.
8 . A method of manufacturing a semiconductor device, the method comprising:
depositing SiOCN to a thickness of between about 20 Å and about 30 Å in physical contact with a gate structure, wherein the depositing the SiOCN comprises:
depositing a first portion of the SiOCN;
treating the first portion of the SiOCN;
after the treating the first portion depositing a second portion of the SiOCN in physical contact with the first portion of the SiOCN; and
treating the second portion of the SiOCN; and
depositing SiOC to a thickness of between about 29 Å and about 45 Å in physical contact with the SiOCN, wherein the depositing the SiOC is performed at least in part with a second cyclical deposition and treatment process.
9 . The method of claim 8 , further comprising replacing the gate structure with a gate all around gate electrode.
10 . The method of claim 8 , further comprising replacing the gate structure with a finFET gate electrode.
11 . The method of claim 8 , wherein the SiOCN has a silicon concentration of about 33%-at., a carbon concentration of about 16%-at., an oxygen concentration of about 47%-at., and a nitrogen concentration of about 4%-at., and wherein the SiOC has a silicon concentration of about 30%-at., a carbon concentration of about 6%-at., and an oxygen concentration of about 64%-at.
12 . The method of claim 8 , wherein the SiOC has a k-value of about 3.8.
13 . The method of claim 8 , wherein the SiOC has a density of about 2.23 g/cm 3 .
14 . The method of claim 13 , wherein the treatment process comprises a plasma treatment.
15 . A semiconductor device comprising:
a gate electrode surrounding at least one nanowire;
a first spacer layer adjacent to the gate electrode, the first spacer layer comprising SiOCN, the SiOCN having a density of at least 2.4 g/cm 3 and a k-value of at least 4.7; and
a second spacer layer in physical contact with the first spacer layer, the second spacer layer comprising SiOC, the SiOC having a density of at least 2.5 g/cm 3 and a k-value of between about 4.7 and about 4.9.
16 . The semiconductor device of claim 15 , wherein the first spacer layer has a silicon percentage of about 32.4%-at., a carbon percentage of about 13.5%-at., an oxygen percentage of about 49.9%-at., and a nitrogen percentage of about 4.2%-at.
17 . The semiconductor device of claim 16 , wherein the second spacer layer has a silicon percentage of about 30%-at., a carbon percentage of about 6%-at., and an oxygen percentage of about 64%-at.
18 . The semiconductor device of claim 15 , wherein the first spacer layer has a thickness of about 25 Å and the second spacer layer has a thickness of about 40 Å.
19 . The semiconductor device of claim 15 , wherein the first spacer layer has a thickness of about 20 Å and the second spacer layer has a thickness of about 45 Å.
20 . The semiconductor device of claim 15 , wherein the first spacer layer has a thickness of about 30 Å and the second spacer layer has a thickness of about 29 Å.