Fabrication and characterization of Yb/MoO?3/(C,Yb) devices

Abstract

In this study we have explored some of the properties of Yb/MoO?3/(C, Yb) thin films as a multifunctional optoelectronic device. While the MoO?3 films which are deposited onto glass substrate are found to be of amorphous nature, the Yb metal induced the growth of orthorhombic phase of MoO?3. The films are high transparent and exhibit energy band gap value of 3.0eV which make it sensitive to light signals in the near ultraviolet range of light. In addition, the frequency dependent capacitance-voltage characteristics of Yb/MoO?3/(C,Yb) structure display pronounced accumulation, depletion and inversion regions that nominate it for use as tunable metal-oxide- semiconductor MOS device. The physical parameters including the built in voltage, barrier height, flat band and threshold voltages of the MOS capacitors are also determined. Furthermore, the current-voltage characteristics displayed high rectification ratio that could reach 1.26×104 at biasing voltage of 0.5V nominating the Yb/MoO?3/C device for use as electronic switches. On the other hand, the impedance spectroscopy analysis in the frequency domain of 0.01–1.80GHz, have shown that the Yb/MoO?3/Yb structures are more appropriate for microwave applications than Yb/MoO?3/C device. The microwave cutoff frequency for the Yb sandwiched MoO?3 exceeds 140GHz. The return loss for the Yb/MoO?3/Yb reaches 26dBat 1.8GHz. These values are attractive as they suit microwave low/high pass band filters.