부산대학교 도서관

Voltage filling pulse measurements taken on a-Si:H/c-Si heterostructure Schottky diode samples are used to examine the capture of electrons from the c-Si substrate into a-Si:H defect states. These measurements, along with the capacitance versus temperature spectra of these diodes, indicate a nearly zero conduction-band offset (50±50 meV). In addition, we have observed trapping of holes at the valence-band discontinuity ΔEv. A clear threshold for the subsequent optical release of these holes yields a value of ΔEv =0.58±0.02 eV. Our measurements also provide the energy and spatial distribution of deep defects within the a-Si:H layer and indicate a region of anomalously large defect density (1018 cm-3) within roughly 350 Å of the a-Si:H/c-Si interface. [ABSTRACT FROM AUTHOR]