New paramagnetic centre and high conductivity in a-Si1−x Rux : H thin films

In this work, the metallic element Ru is introduced into hydrogenated amorphous silicon (a-Si?:?H). The structural and electrical properties of the films doped with Ru have been investigated. Raman spectra reveal that the addition of Ru further disarranges the intrinsically disordered amorphous network and generates more coordinated defects. Meanwhile, a new paramagnetic signal, associated with the holes localized in valence band tail, has been observed. Moreover, the conductivity increases by about nine orders of magnitude with the increase of doping concentration. The temperature coefficient of resistance results show that this material may have a potential application in the infrared detector.