Capacitively-detected magnetic resonance in hydrogenated amorphous silicon solar cells

Spin-dependent transport processes in hydrogenated amorphous silicon (a-Si:H) solar cells at high frequencies are studied with capacitively-detected magnetic resonance (CDMR). A resonant increase of the capacitance at room temperature is found with a g-factor of 2.0055, characteristic for the spin-dependent trapping of electrons at neutral dangling bonds. It is shown that with the help of spin-dependent capacitance measurements quantitative information on the defect density in the device can be obtained, a particular advantage over conventional electrically detected magnetic resonance (EDMR) where resonant changes of the dc conductivity are measured.