Our site saves small pieces of text information (cookies) on your device in order to deliver better content and for statistical purposes. You can disable the usage of cookies by changing the settings of your browser. By browsing our site without changing the browser settings you grant us permission to store that information on your device.
M. A. RAFEA1,* , R. LABUSCH2, F. S. TERRA3, M. MOUNIR4
Pb0.85Sn0.15Te was prepared from its constituent pure elements by melting in helium atmosphere under vacuum of 10-3 Torr. Thin films were deposited from this ingot materials by electron beam evaporation technique on glass and mono-crystalline substrates of KBr, CaF2, mica sheets and BaF2 at substrate temperature 573 K. The films were annealed at 723 K for one hour. The composition of the films are close to the ingot material composition while excess Te was observed the crystallographic orientation [200] was observed to be preferred during the growth process of the film. Hall mobility of the films was observed to be lower than of the mobility of the single crystal. p-type carrier concentration of ~1018 cm-3 at 300 K. Cooling heating cycles process was applied to the films from 100-300 K. The dark and photoconductivity were measured in the same temperature range. It was found the films change due to cooling-heating process. This was discussed briefly and the difference of the thermal expansion coefficient and thermal conductivity between the films and the substrates was pointed out. A model of films-substrates matching was suggested and relations were deduced. It results that the thermally expansion coefficient of the films and the substrates should be close to each other for epitaxial growth. Different substrates with different thermal expansion coefficient, structure, surface properties and unit cell dimension was used in order to verify our suggested model. It was found that the Hall mobility dark conductivity and photoconductivity increase sharply and approach the values of the PbSnTe single crystal for films deposited on single crystalline substrates. The measurements of Hall mobility shows that the carriers are scattered by acoustic phonons. The band gap photoconductivity of the films was measured at different compositions and temperatures under monochromatic IR radiation and the band gap were determined. The results agree well with the theoretical data..
PbSnTe, Thin films, Structure, Photoconductivity, Band gap, Substrate type.
M. A. RAFEA, R. LABUSCH, F. S. TERRA, M. MOUNIR, Effect of substrate type and optimization of the preparation condition for PbSnTe films used as IR photoconductors, Optoelectronics and Advanced Materials - Rapid Communications, 3, 6, June 2009, pp.543-552 (2009).
Submitted at: June 4, 2009
Accepted at: June 15, 2009
Optoelectronics and Advanced Materials - Rapid Communications
(2023): 0.5 - 2023 Journal Citation Reports (Clarivate Analytics, 2024)
Active accounts were imported to the new platform and assigned a random password by default. In order to access your account you need to access the login page and go through the Lost Password dialog (involves the system sending you an email with instructions) in order to reset your password. This step is necessary as passwords are kept in hashed form and the new platform uses modern hashing algorithms incompatible with the previous ones.