Space charge limited current, variable range hopping and mobility gap in thermally evaporated amorphous InSe thin films

• Published in: Journal of materials science. Materials in electronics 2004-12, Vol.15 (12), p.787-792
• Main Authors: VISWANATHAN, C, GOPAL, S, THAMILSELVAN, M, PREMNAZEER, K, MANGALARAJ, D, NARAYANDASS, Sa. K, JUNSIN YI, INGRAM, David C
• Format: Article
• Language: English
• Subjects: Activation energy; Amorphous semiconductors; glasses; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Density; Electrical properties of specific thin films; Electron density; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Electronic transport phenomena in thin films and low-dimensional structures; Exact sciences and technology; Hopping (conductivity); Mathematical analysis; Physics; Space charge; Thin films; X-rays
• ISSN: 0957-4522; 1573-482X
• DOI: 10.1023/B:JMSE.0000045300.00451.51

We have analyzed the properties of as-deposited InSe thin films, deposited onto well cleaned glass substrates under a vacuum of 10^sup -5^ Torr, using X-ray diffraction, Rutherford back scattering, energy dispersive analysis of X-rays, optical transmittance and current-voltage (120-390 K) measurements. Allowed and indirect transition was identified and the mobility gap was determined as 1.44 eV. Under low field (2×10^sup 5^ V cm^sup -1^) and in the temperature range of 300-390 K, space charge limited conduction currents (SCLC) mechanism was observed and the related parameters, such as electron density (n^sub 0^), trap density (n^sub t^), the ratio between free electron density to the total electron density (Θ), mobility (μ) and the effective mobility (μ^sub eff^) of the InSe film of typical thickness 265 nm were calculated and the results are discussed.[PUBLICATION ABSTRACT]