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We report on the space charge spectroscopy studies performed on thermally treated melt-grown single crystal ZnO. The samples were annealed in different ambients at 700 C and also in oxygen ambient at different temperatures. A shallow donor with a thermal activation enthalpy of 27 meV was observed in the as-received samples by capacitance-temperature, CT scans. After annealing the samples, an increase in the shallow donor concentrations was observed. For the annealed samples, E27 could not be detected and a new shallow donor with a thermal activation enthalpy of 35 meV was detected. For samples annealed above 650 C, an increase in acceptor concentration was observed which affected the low temperature capacitance. Deep level transient spectroscopy revealed the presence of five deep level defects, E1, E2, E3, E4, and E5 in the as-received samples. Annealing of the samples at 650 C removes the E4 and E5 deep level defects, while E2 also anneals-out at temperatures above 800 C. After annealing at 700 C, the T2 deep level defect was observed in all other ambient conditions except in Ar. The emission properties of the E3 deep level defect are observed to change with increase in annealing temperature beyond 800 C. For samples annealed beyond 800 C, a decrease in activation enthalpy with increase in annealing temperature has been observed which suggests an enhanced thermal ionization rate of E3 with annealing. V C 2013 American Institute of Physics. [http://dx

A commercially available metalorganic compound, namely Bis (2,2,6,6-tetramethyl-3, 5-heptanedionato)(1,5-cyclooctadiene)Ruthenium, or Ru(THD)2COD was evaluated for growth, nanostructure, and conformality of ruthenium films using a manufacturable, liquid-source metalorganic chemical vapor deposition technique. The deposition of Ru films (60–200 nm) was carried out on various substrates at a temperature (Tsub) of 250–320 °C via the oxygen-assisted pyrolysis of Ru(THD)2COD. In the kinetically controlled regime, the activation energy for the deposition of Ru on amorphous-HfO2/SiO2/Si was 136 kJ/mol. However, at Tsub>290 °C, the nearly temperature-independent growth rate was indicative of the mass-transport controlled regime. The as-deposited Ru films exhibited dense and polycrystalline grain structure, with a moderate preference for the (001) orientation. X-ray photoelectron spectroscopy revealed the presence of RuO2 in metallic Ru films deposited at a Tsub as low as 260 °C. In addition, high-resolution transmission electron microscopy showed amorphous grain boundaries in Ru films and a disorder interface layer between Ru and HfO2 surface. The Ru films, however, were electrically conductive (27 μΩ cm). In addition, Ru films deposited on patterned TiN/Si substrates in the kinetically controlled regime at 250 °C exhibited nearly 100% step coverage.

This paper reports on the deposition of pure and 5 at.% Al doped ZnO (AZO) prepared by sol-gel and applied to the substrates by spin-coating, and the role of annealing temperature on the crystallinity of these layers. It is found that both ZnO and AZO are largely amorphous when coated on glass compared to n-Si(111), as substrates. On both substrates, X-ray diffraction (XRD) shows that the crystallinity improves as annealing temperature is raised from 200 to 600 °C with better crystallinity on Si substrates. The thickness of the films on substrates was determined as 120 nm by Rutherford backscattering spectroscopy (RBS). Specular ultra-violet visible (UV-vis) gives the direct transition optical band gaps (Eg) for AZO as-deposited films are 2.60 and 3.35 eV while that of 600 °C annealed films are 3.00 and 3.60 eV. The Eg calculated from diffuse reflectance spectroscopy (DRS) UV-vis are more diverse in ZnO-and AZO-Si than the ZnO-and AZO-glass samples, although in both sets the Eg tend to converge after annealing 600 °C. The Raman spectra of samples show multiphonon processes of higher order from the AZO and substrates. It is found that residual stresses are related to E2 Raman mode.

Deep level transient spectroscopy (DLTS),