Silicon nitride films for semiconductor device applications

A method for forming a film stack including a silicon nitride film and a second film on a substrate, the silicon nitride film having a different material composition from the second film, the method comprising:

• (a) depositing the silicon nitride film on the substrate by plasma-enhanced chemical vapor deposition while flowing a silicon-containing reactant, a nitrogen-containing reactant, and a boron-containing reactant through the plasma-enhanced chemical vapor deposition apparatus containing the substrate, wherein the silicon nitride film has a thickness of between about 10 and 100 nm;
• (b) depositing the second film on the silicon nitride film, wherein the second film has a thickness of between about 10 and 100 nm;
• and
• (c) repeating (a) and (b) at least twice to form the film stack.

A plasma-enhanced chemical vapor deposition apparatus configured to deposit a film stack on a substrate, the apparatus comprising:

• a process station;
• a first reactant feed for supplying a silicon-containing reactant to the process station;
• a second reactant feed for supplying a co-reactant to the process station;
• a plasma source;
• and
• a controller configured to control the apparatus to maintain a plasma and process gas flow conditions, the controller comprising instructions for
• (a) depositing a silicon nitride film on the substrate by plasma-enhanced chemical vapor deposition while flowing the silicon-containing reactant, a nitrogen-containing reactant, and a boron-containing reactant through the plasma-enhanced chemical vapor deposition apparatus containing the substrate, wherein the silicon nitride film has a thickness of between about 10 and 100 nm;
• and
• (b) depositing the second film on the silicon nitride film, wherein the second film has a thickness of between about 10 and 100 nm.