The electron-spin resonance spectrum of diamond film synthesized by chemical vapor deposition

The electron-spin resonance (ESR) spectrum of diamond films of high quality and free-standing form was investigated. The ESR spectrum of diamond film has been believed to be composed of a main line and two shoulders. The main line has been attributed to a superposition of two components at two different phases in the film. We found that the spectrum is composed of a slightly asymmetric line and two shoulders. The shape of the asymmetric line did not change even when the film was etched by an oxygen plasma so that the thickness of the film was halved. We propose that the main line can be attributed to a single component with an anisotropic g tensor of axial symmetry.