In vacuo measurements of dangling bonds created during Ar-diluted fluorocarbon plasma etching of silicon dioxide films

Dangling bond creation processes during fluorocarbon plasma etching of silicon dioxide (SiO2) films were studied using an in vacuo electron spin resonance technique. In a range of about 10nm underneath the interface of the SiO2 films with an amorphous fluorinated carbon film that was top-covered, a Si dangling bond in the films (E′ center, g value 2.0003) was located. Density of the E′ center was sustained during etching processes created by the illumination of vacuum ultraviolet emissions, higher photon energy than the bandgap of SiO2. The etching mechanism in this system is discussed taking into account the experimental results.