Physical properties of CdSe thin films produced by thermal evaporation and e-beam techniques

Huş, Şaban Mustafa
CdSe thin films were deposited by thermal evaporation and e-beam evaporation techniques on to well cleaned glass substrates. Low dose of boron have been implanted on a group of samples. EDAX and X-ray patterns revealed that almost stoichiometric polycrystalline films have been deposited in (002) preferred orientation. An analysis of optical measurements revealed a sharp increase in absorption coefficient below 700 nm and existence of a direct allowed transition. The calculated band gap was around 1.7 eV. The room temperature conductivity values of the samples were found to be between 9.4 and 7.5x10-4 (Ω-cm)-1 and 1.6x10-6 and 5.7x10-7 (Ω-cm)-1for the thermally evaporated and e-beam evaporated samples respectively. After B implantation conductivity of these films increased 5 and 8 times respectively. Hall mobility measurements could be performed only on the thermally evaporated and B-implanted e-beam evaporated samples and found to be between 8.8 and 86.8 (cm2/V.s). The dominant conduction mechanism were determined to be thermionic emission above 250 K for all samples. Tunneling and v variable range hopping mechanisms have been observed between 150-240 K and 80- 140 K respectively. Photoconductivity illumination intensity plots indicated two recombination centers dominating at the low and high regions of studied temperature range of 80-400 K. Photoresponse measurements have corrected optical band gap measurements by giving peak value at 1.72 eV.


Isochronal hydrogenation of textured magnesium/palladium thin films
Özgit, Çağla; Öztürk, Tayfur; Department of Metallurgical and Materials Engineering (2009)
Pure and palladium‐covered 350 nm thick magnesium thin films were deposited on glass substrates via thermal evaporation. In the as‐deposited state, films were highly textured with Mg (001) parallel to the substrate. Hydrogen loading experiments were carried out in two different conditions; namely isothermal and isochronal. Hydrogenation behaviors of the thin films were followed by twopoint probe electrical resistance and optical transmittance measurements, as well as x‐ray diffraction studies. Isothermal hy...
Deposition of AgGaS2 thin films by double source thermal evaporation technique
KARAAĞAÇ, HAKAN; Parlak, Mehmet (Springer Science and Business Media LLC, 2011-09-01)
In this study, polycrystalline AgGaS2 thin films were deposited by the sequential evaporation of AgGaS2 and Ag sources with thermal evaporation technique. Thermal treatment in nitrogen atmosphere for 5 min up to 700 A degrees C was applied to the deposited thin films and that resulted in the mono phase AgGaS2 thin films without the participation of any other minor phase. Structural and compositional analyses showed the structure of the films completely changes with annealing process. The measurements of tra...
Investigation of electromigration induced hillock and edge void dynamics on the interconnect surface by computer simulation
Çelik, Aytaç; Oğurtanı, Tarık Ö.; Department of Metallurgical and Materials Engineering (2004)
The Electromigration-induced failure of metallic interconnects is a complicated process, which involves flux divergence, vacancy and atom accumulation with or without compositional variations, void and hillocks nucleation, growth and shape changes. Hillocks and surface void dynamics in connection with the critical morphological evaluation have been investigated in order to understand the conditions under which premature failure of metallic thin interconnects occur. In this thesis, an interconnect is idealiz...
Structural characterization of Zn-In-Se thin films
Gullu, H. H.; Parlak, Mehmet (World Scientific Pub Co Pte Lt, 2017-02-20)
In this study, structural properties of the Zn In Se (ZIS) thin films deposited by thermal evaporation method were investigated. The as-grown and annealed ZIS films were found in polycrystalline structure with the main orientation in (112) direction. The compositional analysis of the films showed that they were in Zn-rich behavior and there was a slight change in the elemental contribution to the structure with annealing process. Raman analysis was carried out to determine the crystalline structure and the ...
Heterojunction solar cells with integrated Si and ZnO nanowires and a chalcopyrite thin film
KARAAĞAÇ, Hakan; Parlak, Mehmet; YENGEL, Emre; Islam, M. Saif (Elsevier BV, 2013-06-15)
ZnO nanowires (NWs) have been successfully synthesized using a hydrothermal technique on both glass and silicon substrates initially coated with a sputtered ZnO thin film layer. Varying ZnO seed layer thicknesses were deposited to determine the effect of seed layer thickness on the quality of ZnO NW growth. The effect of growth time on the formation of ZnO NWs was also studied. Experimental results show that these two parameters have an important effect on formation, homogeneity and vertical orientation of ...
Citation Formats
Ş. M. Huş, “Physical properties of CdSe thin films produced by thermal evaporation and e-beam techniques,” M.S. - Master of Science, Middle East Technical University, 2006.