Browsing by Author "Lee, Shao-Yi"

Now showing 1 - 2 of 2

Effects of Doping Ratio and Thermal Annealing on Structural and Electrical Properties of Boron-Doped ZnO Thin Films by Spray Pyrolysis
(2013-06-01)
Yu, Cheng-Chang
;
Hsu, Yu-Ting
;
Lee, Shao-Yi
;
Lan, Wen-How
;
Kuo, Hsin-Hui
Boron-doped zinc oxide (BZO) thin films have been fabricated by spray pyrolysis on a glass substrate. The morphology and electrical properties of the thin films were investigated. X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses were performed. It was found that [B]/[Zn] ratio altered both the microstructure and concentration of the BZO thin films. The film grain size was reduced by increasing the [B]/[Zn] ratio. The highest Hall mobility was 3.65 cm(2)V(-1)s(-1) for the undoped ZnO thin film, and the highest carrier concentration of 1.0 x 10(19) cm(-3) was achieved for the as-deposited BZO thin film with [B]/[Zn] = 1.5 at. %. Conductivity was determined at different measurement temperatures and shallow donors provided the dominate conduction mechanism for the as-deposited BZO thin films. After 600 degrees C annealing, shallow level reduction and donors with a high activation energy of 129 +/- 6 meV in the BZO thin films were characterized, and the shallow donors that dominate the carrier concentration for the as-deposited spray-pyrolized BZO thin film were eliminated. (C) 2013 The Japan Society of Applied Physics
Thickness Study of Er-Doped Magnesium Zinc Oxide Diode by Spray Pyrolysis
(2018-12-01)
Hsu, Yu-Ting
;
Lee, Che-Chi
;
Lan, Wen-How
;
Huang, Kai-Feng
;
Chang, Kuo-Jen
Erbium-doped magnesium zinc oxides were prepared through spray pyrolysis deposition at 450 degrees C with an aqueous solution containing magnesium nitrate, zinc acetate, erbium acetate, and indium nitrate precursors. Diodes with different erbium-doped magnesium zinc oxide thicknesses were fabricated. The effect of erbium-doped magnesium zinc oxide was investigated. The crystalline structure and surface morphology were analyzed using X-ray diffraction and scanning electron microscopy. The films exhibited a zinc oxide structure, with (002), (101), and (102) planes and tiny rods in a mixed hexagonal flakes surface morphology. With the photoluminescence analyses, defect states were identified. The diodes were fabricated via a metallization process in which the top contact was Au and the bottom contact was In. The current-voltage characteristics of these diodes were characterized. The structure resistance increased with the increase in erbium-doped magnesium zinc oxide thickness. With a reverse bias in excess of 8 V, the light spectrum, with two distinct green light emissions at wavelengths of 532 nm and 553 nm, was observed. The light intensity that resulted when using a different operation current of the diodes was investigated. The diode with an erbium-doped magnesium zinc oxide thickness of 230 nm shows high light intensity with an operational current of 80 mA. The emission spectrum with different injection currents for the diodes was characterized and the mechanism is discussed.