Utilization of residual CdCl2 in CBD-CdS to realize grain growth in CdTe: A novel route

• Published in: Materials research bulletin Vol. 48; no. 11; pp. 4711 - 4717
• Main Authors: Ghosh, B., Ghosh, D., Hussain, S., Chakraborty, B.R., Dalai, M.K., Sehgal, G., Bhar, R., Pal, A.K.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.11.2013
• Subjects: A. Thin films; C. Atomic force microscopy; C. Electron microscopy; Semiconductors; 78.55.Et; 78.66.Sq; A. Thin films; Semiconductors; C. Atomic force microscopy; C. Electron microscopy; 81.15.−z
• ISSN: 0025-5408; 1873-4227
• DOI: 10.1016/j.materresbull.2013.08.006

•Grain growth in CdTe using residual CdCl2 in CBD-CdS.•Excellent interface boundaries studied by TOF-SIMS.•Eliminating the additional steps of CdCl2 treatment after CdTe deposition for grain growth. CdTe films were deposited by thermal evaporation onto chemical bath deposited CdS (CBD-CdS) films. The composite films were subjected to rapid thermal annealing (RTA) to observe simultaneous grain growth in both the CdS and CdTe layers. The films were characterized by measuring the compositional, microstructural and photoluminescence (PL) properties. PL spectra is dominated by the characteristic peaks (∼1.42eV and ∼1.26eV) associated with the virgin CdTe film. Additional features located at ∼2.56eV and ∼1.99eV could also be detected. The Fourier Transform Infra Red (FTIR) peak at ∼482cm−1 appeared due to the simultaneous presence of absorption peaks for CdTe stretching mode as well as Cd-S modes. Appearance of the broad peak between 1000cm−1 and 1165cm−1 may be an indication of interfacial alloying. Secondary ion mass Spectroscopy (SIMS) measurements were done to observe the compositional uniformity in the film and to measure the interfacial mixing behaviour.