Chemical bath deposition (CBD), a direct low cost technique that involves a cadmium salt solution, a complexing agent and a chalcogen source, was used to prepare CdSe semiconductor films. The most favourable conditions for acceptable quality CdSe films grown on glass were obtained. Commercially available microscope glass slides (with a size of 1 cm × 1 cm × 1 mm) were used as substrates to deposit CdSe films. CdSe films were deposited in a freshly prepared aqueous solution containing CdSO 4 (0.2 -0.4 M), NH 4 OH (3.8 -14 M) as a complexing agent for slow release of Cd 2+ ions, and Na 2 SeSO 3 (0.118 and 0.16) as a source of Se 2-ions. The solutions were prepared in deionized water. The glass slides were immersed in a mixture of CdSO 4 -NH 4 OH for 5 min before the solution of Na 2 SeSO 3 was added. The bath temperature varied from 20 to 60 °C. Structural and morphological quality of the films was analyzed by XRD, SEM, EDS, and XPS. The results show that the crystallinity of the CdSe films as-deposited is improved by increasing temperature. The initial growth stages of CdSe films at 20 and 60 °C start on CdO x and Cd(OH) 2 buffer layers respectively.

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The AC temperature technique is used to develop a calorimeter probe for measuring the specific heat of small samples. A commercial closed-cycle refrigerator operating in the 8 - 300 K temperature range was used as a cryogenic station. A theory of operation is presented and the experimental set-up is discussed. The calorimeter has been used to study the nature of the magnetic and order - disorder phase transitions of several materials. Specific heat data taken from a sample of chromel alloy (90% Ni - 10% Cr) and a single-crystal sample of show that the sensitivity of the apparatus to relative variations in the specific heat is about 0.1%.

The sintering of different ZnO nanostructures by the thermal decomposition of zinc acetate is reported. Morphological changes from nanorods to nanoparticles are exhibited with the increase of the decomposition temperature from 300 to 500°C. The material showed a loss in the crystalline order with the increase in the temperature, which is correlated to the loss of oxygen due to the low heating rate used. Nanoparticles have a greater vibrational freedom than nanorods which is demonstrated in the rise of the main Raman modeE 2(high) during the transformation. The energy band gap of the nanostructured material is lower than the ZnO bulk material and decreases with the rise in the temperature.