Ro. Dusane et al., STRUCTURAL DEFECTS IN GLOW-DISCHARGE A-SI-C-H INVESTIGATED BY POSITRON-ANNIHILATION SPECTROSCOPY, Journal of applied physics, 76(1), 1994, pp. 242-245
Glow discharge deposited hydrogenated amorphous silicon carbon alloy f
ilms with varying carbon content are studied for structural defects by
positron lifetime spectroscopy. Measurements of optical properties li
ke refractive index (n) and band gap (E(g)) which indirectly reflect t
he varying carbon content in the films have also been made. The increa
sed defect density in these films with increasing carbon content is ve
ry clearly indicated by the positron lifetime data. The nature of thes
e defects and their relative concentrations are determined from the po
sitron lifetime and intensity values. Interestingly a continuous trans
formation from one type of defect to the other with increasing carbon
is indicated by these results.