Abstract
In this thesis, transparent metal oxides for near-infrared (NIR) and near-ultraviolet (NUV) are prepared and discussed, and their applications are further indicated. Indium molybdenum oxide (IMO) exhibited the material characteristic of valence difference of 3 between the In3+ matrix and Mo6+ dopants is feasible for NUV device applications. The optimum IMO film shows the characteristics of low electrical resistivity of 3.55 × 10-4 Ω-cm and high optical transmittance of 99% at 968 nm. Afterwards, a high-speed and high-light-output-power InGaAs/GaAs NIR LED at 968 nm wavelength employing IMO contact is constructed. As compared to NIR LED using AuGe contact, NIR LED using IMO contact produces a light output power with a rate of 5.7 μW/mA, which is twice of 2.7 μW/mA for NIR LED using AuGe contact at corresponding injection current level. These NIR LEDs exhibit the 3-dB optical bandwidth of 649 MHz, which is correlated to the carrier recombination lifetime of 245 ps. Besides, the IMO exhibits characteristic of high work function around 4.93 eV. Thus, the incorporation of IMO contact and P3HT/PCBM organic solar cells is discussed. Solar cell using optimum IMO contact shows an higher electrical power efficiency of 3.77%. Furthermore, indium gallium zinc oxide (IGZO) is constructed for future NUV applications. The optimization of IGZO preparation process is realized. IGZO with the wide optical band gap of 3.7 eV, shows a low electrical resistivity of 7.16 × 10-4 Ω-cm and a high optical transmittance in NUV wavelengths. IGZO is the alluring transparent contact for NUV device applications.