Transparent conducting oxides have been widely employed in optoelectronic devices using the various deposition methods such as sputtering, thermal evaporator, and e-gun evaporator technologies.<sup>1-3</sup> In this work, gallium doped zinc oxide (ZnO:Ga) thin films were grown on glass substrates via H<sub>2</sub>O-thermal atomic layer deposition (ALD) at different deposition temperatures. ALD-GZO thin films were constituted as a layer-by-layer structure by stacking zinc oxides and gallium oxides. Diethylzinc (DEZ), triethylgallium (TEG) and H<sub>2</sub>O were used as zinc, gallium precursors and oxygen source, respectively. Furthermore, we investigated the influences of O<sub>2</sub> plasma post-treatment power on the surface morphology, electrical and optical property of ZnO:Ga films. As the result of O<sub>2</sub> plasma post-treatment, the characteristics of ZnO:Ga films exhibit a smooth surface, low resistivity, high carrier concentration, and high optical transmittance in the visible spectrum. However, the transmittance decreases with O<sub>2</sub> plasma power in the near- and mid-infrared regions.
In this work, an analytical study of the temperature dependence of current gain and ideality factor (η)
has been performed for the heterojunction bipolar light emitting transistor (HBLET). In order to utilize
the radiative recombination, the structure of HBT embedded two quantum wells in the base region
which can improve the radiation efficiency. Compare with the convention HBT, the temperature
dependence of current gain increases 42.5% with increasing temperature from 350K followed by a
decrease towards 300K. Variation of gain with temperature is different from that the characteristic of
HBT adding another advantage in favor of the HBLET. The η<sub>B</sub> of these devices are similar, revealing
that the space-charge recombination dominates the overall base current. The high output power of
HBLET is 962 μW at 88 mA. These results reveal that the HBLET which combine electrical and
optical characteristic device.