Remote plasma activated nitridation

A nitrogen precursor that has been activated by exposure to a remotely excited species is used as a reactant to form nitrogen-containing layers. The remotely excited species can be, e.g., N2, Ar, and/or He, which has been excited in a microwave radical generator. Downstream of the microwave radical generator and upstream of the substrate, the flow of excited species is mixed with a flow of NH3. The excited species activates the NH3. The substrate is exposed to both the activated NH3 and the excited species. The substrate can also be exposed to a precursor of another species to form a compound layer in a chemical vapor deposition. In addition, already-deposited layers can be nitrided by exposure to the activated NH3 and to the excited species, which results in higher levels of nitrogen incorporation than plasma nitridation using excited N2 alone, or thermal nitridation using NH3 alone, with the same process temperatures and nitridation durations.