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N-doped ZnO films have been grown on (0 0 0 1) sapphire substrates by a novel low-pressure plasma-assisted metalorganic chemical vapor deposition system using N2O plasma as doping source. X-ray photoelectron spectroscopy analysis confirmed the incorporation of N into the ZnO films. Room temperature p-type conduction was achieved for the N-doped ZnO film at suitable substrate temperatures, with the resistivity of 8.71 Ω cm, hole concentration up to 3.44 × 1017 cm−3 and mobility of 2.09 cm2/V s. In the photoluminescence (PL) measurement, a strong near-band-edge emission was observed for both undoped and N-doped films, while the deep-level emission was almost undetectable, which confirmed that the obtained ZnO-based films were well close to stoichiometry and of optically high quality.

Zn 1– x (Mg,Cd) x O films were deposited on single crystal Si (1 0 0) substrate using ultrasonic spray pyrolysis under ambient atmosphere. The X-ray diffraction patterns confirmed the existence of a ZnO single-phase with a hexagonal wurtzite structure. A strong ultraviolet near-band-edge emission was observed in the room temperature photoluminescence measurement for all the as-grown Zn 1– x (Mg,Cd) x O films, while the deep-level emission was almost undetectable, suggesting that the obtained Zn 1– x (Mg,Cd) x O films are well close to stoichiometry and of optically high quality. The tunableness of optical emission spectra from 358 to 422 nm was realized by adjusting the Mg (Cd) concentration in the Zn 1– x (Mg,Cd) x O films at extremely low cost. The photoluminescence spectra as a function of temperature were also investigated to examine the emission mechanism of Zn 1– x (Mg,Cd) x O films.

To realize practical application of short-wavelength optoelectronic devices (such as light emitting diodes, LEDs, and LDs) based on ZnO materials, electroluminescence (EL) from ZnO based junction device is pivotal. In this article, ZnO based devices with different structures were grown on single-crystal GaAs(1 0 0) substrate by ultrasonic spray pyrolysis. The ZnO homojunction was comprised of N–In codoped p-type ZnO and unintentionally doped n-type ZnO film. Moreover, heterojunction device with n-ZnMgO/ZnO/p-ZnMgO structure was also grown on single-crystal GaAs(1 0 0) substrate by the same method. Ohmic contact layer on n-type ZnO layer and GaAs substrate were formed by Zn/Au and Au/Ge/Ni electrodes, respectively. Distinct light emission was observed under forward current injection at room temperature. The origin of electroluminescence emission was supposed to be attributed to a radiative recombination through deep-level defects in the structure.