Boron derived materials deposition method
Methods of forming boron-containing films are provided. The methods include introducing a boron-containing precursor into a chamber and depositing a network comprising boron-boron bonds on a substrate by thermal decomposition or a plasma process. The network may be post-treated to remove hydrogen from the network and increase the stress of the resulting boron-containing film. The boron-containing films have a stress between about −10 GPa and 10 GPa and may be used as boron source layers or as strain-inducing layers.
1. A method of forming a boron-containing film, comprising:
introducing a boron-containing precursor into a chamber;
depositing a network comprising boron-boron bonds on a substrate in the chamber from the boron-containing precursor by a thermal decomposition process in the absence of a plasma;
post-treating the network comprising boron-boron bonds to remove hydrogen from the network, wherein the post-treated network forms a boron-containing film that has a stress between about −10 GPa and about 10 GPa.
2. The method of claim 1 , wherein the post-treating comprises a treatment selected from the group consisting of a plasma process, a UV cure process, a thermal anneal process, and combinations thereof.
3. The method of claim 1 , further comprising repeating the introducing, depositing, and post-treating until a desired thickness of the boron-containing film is obtained.
4. The method of claim 1 , further comprising using the boron-containing film to dope an underlying layer with boron.
5. The method of claim 1 , wherein the network comprising boron-boron bonds comprises between about 3 and about 50 atomic percent hydrogen.
6. The method of claim 1 , further comprising introducing an additional precursor into the chamber to modify the composition of the boron-containing film, wherein the additional precursor is selected from the group consisting of a silicon-containing precursor, a carbon-containing precursor, a nitrogen-containing precursor, and combinations thereof.
7. The method of claim 6 , wherein the additional precursor acts as a porogen and is substantially removed from the network by the post-treating.
8. The method of claim 7 , wherein the porogen removal from the network by the post-treating leads to a tensile stress increase in the boron-containing film.
9. The method of claim 6 , wherein the additional precursor is a nitrogen-containing precursor that adds nitrogen to the network.
10. A method of processing a substrate, comprising:
depositing a boron-containing film on a transistor structure on a substrate;
depositing a premetal dielectric layer on the boron-containing film;
etching the premetal dielectric layer and the boron-containing film to form a contact via to a gate stack of the transistor structure; and
sealing regions of the boron-containing film that are exposed by the etching, wherein the depositing the boron containing film comprises:
introducing a boron-containing precursor into a chamber; and
depositing a network comprising boron-boron bonds on the substrate in the chamber from the boron-containing precursor by a thermal decomposition process in the absence or presence of a plasma, wherein depositing the boron-containing film further comprises: post-treating the network comprising boron-boron bonds to remove hydrogen from the network, wherein the post-treated network forms a boron-containing film that has a stress between about −10 GPa and about 10 GPa.
11. The method of claim 10 , wherein the boron-containing film has high conductivity lower than 100 mOhm*cm.
12. The method of claim 10 , wherein the boron-containing film has a conformality over 90% when deposited on patterned structures.