Influences of trace metal impurities on the thermal quenching of photoluminescence in hydrogenated amorphous silicon by homogeneous chemical vapor deposition.

The influence of trace metal impurities of low-temperature undoped amorphous silicon by homogeneous chemical vapor deposited a-Si:H has been explored for the first time. The metal impurities Ni, Cr, and Fe cause a shift of the transition temperature for the double-activated regime to a relatively low value. However, Ga and B impurities quench the photoluminescence intensity at a low temperature. Both of them cause weak photoemission of the films at room temperature. The shift of the transition temperature can be explained by the presence of non-radiative deep recombination centers. The quenching of the photoluminescence intensity is caused by the presence of nonradiative recombination centers. [ABSTRACT FROM AUTHOR]