A ZnO-Nanowire Phototransistor Prepared on Glass Substrates

The fabrication of a phototransistor via the bridging of two prefabricated electrode; with a laterally grown ZnO nanowire is reported. It was found that the fabricated device is an n-channel enhancement mode phototransistor with a dark carrier concentration of 6.34 x 10(17) cm(-3) when the gate voltage is biased at 5 V. With an incident-light wavelength of 360 nm and a zero gate bias, it was found that the noise equivalent power and normalized detectivity (D*) of the fabricated ZnO phototransistor were 6.67 x 10(-17) W and 1.27 x 10(13) cm H-z(0.5) W-1, respectively. It was also found that the current in the device can be modulated efficiently by tuning the wavelength of the excitation source.