Journal of Vacuum Science & Technology A, Vol.27, No.6, 1343-1346, 2009
UV detection based on a ZnO/LiNbO3 layered surface acoustic wave oscillator circuit
This study elucidates the combination of an oscillator circuit with a high-frequency amplifier, a matching network, and a layered surface acoustic wave device for detecting ultraviolet (UV) light. The oscillator circuit shows an excellent performance with the resonance frequency of 109.34 MHz and phase noise of -107.137 dB at 100 kHz. The frequency shift that is caused by the interaction between the acoustic wave and carriers upon excitation by UV light in the ZnO thin film is discussed. The frequency variation of the oscillator steadily increases with the intensity of the UV light. An extreme frequency shift of 63.75 kHz was observed as the UV light intensity reached 1250 mu W/cm(2). (C) 2009 American Vacuum Society. [DOI: 10.1116/1.3222916]