Boron doping on the structural, optical and electrical properties in BZO films fabricated by spray pyrolysis were investigated. The carrier concentration of ~10¹⁹cm^-3 and optical transmittance about 90% in the infrared region was achieved.

The transparent film calcium zinc oxide with indium doping was prepared by spray pyrolysis with calcium nitrate, zinc acetate and indium nitrate precursors. With the increasing of calcium nitrate concentration, the blue shift of cutoff wavelength in the film transmission spectra can be observed. The optical bandgap for ZnO:In and CaZnO:In thin films were 3.34 and 3.41 eV, respectively. N-type conduction was observed for the indium doped thin films. With the increasing of indium nitrate concentration, the film conductivity, concentration and mobility were characterized. The indium doped CaZnO thin film shows the talent performance in the application of high band gap transparent conducting film.

The p-Si/n-MgZnO:Er/Ga₂O₃/ZnO:In diodes with different Ga₂O₃ thicknesses were fabricated through spray pyrolysis deposition at 450 °C with aqueous solutions containing magnesium nitrate, zinc acetate, erbium acetate, gallium nitrate, and indium nitrate precursors. The effects of Ga₂O₃ layer thickness on the diode properties were investigated. For the deposited films, a combined tiny hexagonal slices and small blocks surface morphology was characterized by scanning electron microscopy for all samples. Diodes were formed after In and Ag deposition on the back side and top side, respectively. The current-voltage characteristics and luminescence spectra are studied. With the increasing of Ga₂O₃ thickness, the diode forward bias resistance increases while the reverse biased dark current shows the decrease-increase characters. The Er ion corresponded green light emission was characterized for the diode under reverse biased breakdown condition. The increased luminescent intensity with low turn-on current behaviors was characterized by the diode with a Ga₂O₃ thickness of 4.9 nm. With the diode electrical and luminescence analysis, the effect of the Ga₂O₃ barrier layer on the diode was discussed. The Ga₂O₃ barrier layer improves performance for rare earth-related light-emitting devices.

Here, we present the output characteristics of a semiconductor laser diode with two circular ring resonators. The material of the laser diode is a metal organic chemical vapor deposition (MOCVD)-grown InGaAlP multiple-quantum-well (MQW) structure. The current injection of the laser diode is confined by the ridge waveguide of two circular ring resonators connected by two directional couplers. The confined light output through the nonwaveguide region of the substrate was observed. Measurements of light–current (L–I) and spectral characteristics at each output terminal were presented. These measurements showed asymmetric output characteristics of emission from two directional coupling terminals. In addition, output characteristics of a laser diode device with larger diameter ring resonators showed shifting of the lasing emission wavelength from a different side of the output coupling terminal.

Fiber Bragg Grating (FBG) is popularly used for temperature and stress sensors due to its reflection which is crucial to the variation of ambient temperature and mechanical stress. However, there are fewer applications of FBG sensors to identify a liquid solution. When the cladding of the FBG is removed, the index of the liquid solution can then effectively change the index periodicity of the FBG. We fabricated an FBG sensor with the depletion of the cladding layer and the characterization of its wavelength shift to measure different sugar content at different temperatures.