The numerical chemical-kinetic model was updated for inductively coupled nitrogen plasma (nitrogen ICP),
and the number densities of N2 excited states were obtained through self-consistent calculations. As a result
of these calculations, it was found that electron temperature Te and the number density ratio of N2(C) to
N2(B) were positively correlated. This finding can expand the possibility of OES measurement in nitrogen
ICP, as Te can be estimated from the number density ratio of N2(C) to N2(B) derived from optical emission
spectroscopy (OES) measurement.