Light-induced effects in a-Si:H(Er)

• Published in: Materials science & engineering. B, Solid-state materials for advanced technology Vol. 105; no. 1; pp. 153 - 156
• Main Authors: Birukov, A.V., Fenuchin, A.V., Kazanskii, A.G., Terukov, E.I.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.12.2003
• Subjects: a-Si:H films; Erbium; Light-induced structural change; a-Si:H films; Light-induced structural change; Erbium
• ISSN: 0921-5107; 1873-4944
• DOI: 10.1016/j.mseb.2003.08.034

While the luminescence of a-Si:H(Er) has been studied quite extensively there is no data on the light-induced effects in this material. The latter, however, are important for electroluminescent devices. We have investigated the light-induced metastable state in a-Si:H(Er) with the measurements of optical absorption in the below-gap region and dark conductivity before and after illumination of the films by band gap light. PECVD a-Si:H(Er) films prepared under various conditions have been studied. To elucidate the details concerning the peculiarities of light-induced phenomena in a-Si:H(Er) the obtained results have been compared with the data for a-Si:H(As) films with similar Fermi level position. We have found that after long illumination time the changes of electric properties of a-Si:H(Er) films were determined by dangling bond creation as in a-Si:H(As) film. For short illumination time the persistent photoconductivity was observed in a-Si:H(Er) films. A possible origin of this phenomenon is discussed from the viewpoint of structural disorder induced by erbium–oxygen complexes incorporation.