Thin ZnO films were directly grown on p-Si(1 0 0) substrates by photoinduced electrodeposition under illumination. In this case, p-Si wafer behaves as a photocathode. At the initial deposition stage, it has been found that the ZnO films grew through three-dimensional instantaneous nucleation followed by diffusion-limited growth mode. In this study, we report that the conductivity type of ZnO films can be changed from n-type to p-type by varying the relative concentration of oxygen in ZnO films through the thermal treatment in air ambient without any doping process. The electrical properties of ZnO/p-Si heterojunctions were investigated via current–voltage (I–V) characteristics. These heterojunctions showed good diode-like, rectifying I–V characteristics and the turn-on voltages of the n-ZnO/p-Si and p-ZnO/p-Si heterojunctions were found to be 0.56 and 0.46 V. From the analysis of temperature dependence of the I–V characteristics, these heterojunctions exhibited that the charge carriers are mainly transported by the activation of the carriers across the barrier height but in a low voltage region under forward bias, transported through the multi-step tunnelling-assisted carrier capture-emission mechanism.

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Transition related to the Mn–Zn interaction was observed in photoluminescence (PL) study of the InMnP:Zn epilayer and the peak position blueshifted with increasing Mn concentration. X-ray photoelectron spectroscopy was used to clarify the blueshift of the PL peak. The binding energy shifts of Mn 2p and Zn 2p core levels indicative of the interaction between Mn and Zn were observed. This mutual interaction between Mn 2p and Zn 2p agrees with the result that the Mn-related transition in InMnP:Zn codoped with Zn is shifted to the higher energy region in comparison with InMnP without additional doping of Zn.

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The growth of Ti and the formation of epitaxial Ti silicide on Si(111)-7×7 were investigated by using reflection high-energy electron diffraction (RHEED) and high-resolution transmission electron microscopy (HRTEM). The growth mode of Ti is Stransky–Krastanov type when the substrate temperature is room temperature (RT). On the other hand, it is Volmer–Weber type when the substrate temperature is ∼550 °C. The HRTEM lattice image and transmission electron diffraction pattern show that C54 TiSi2 is grown epitaxially on a Si substrate when 160 ML of Ti is deposited on a Si(111)-7×7 surface at RT followed by in situ annealing at 750 °C for 10 min in ultrahigh vacuum (UHV). The TiSi2/Si interface is somewhat incoherent, but the developed TiSi2 crystallites are single crystal with matching face relationships of TiSi2(111)∥Si(111), TiSi2(311)∥Si(111), and TiSi2(022)∥Si(111). A thin single-crystal Si overlayer with [111] direction is grown on the TiSi2 surface when TiSi2/Si(111) is annealed at ∼900 °C in UHV, which is confirmed by observing the Si(111)-7×7 RHEED pattern.