Enhancement of Electrical Performance of MoO3 Films via Indium Nano Sandwiching رسالة ماجستير

Abstract

In this thesis the impact of the Indium nanolayers on the characteristics of MoO3 thin films are explored. Indium metallic nano- layers of thicknesses of 50, 75, 100 and 200 nm are sandwiched between two 500 nm thick MoO3 thin films. The X-ray diffraction technique is used to find out the structural properties of the MoO3 and MoO3/In/MoO3 layers. In accordance with this technique, MoO3 exhibit crystalline form called orthorhombic structure α-MoO3 phase. The indium induced formation of crystalline phase when its thickness exceeds 50 nm. In addition, the impact of the indium thickness on the electrical performance of the films was searched in a wide range of temperature. It was observed that the dielectrical conductivity is highly sensitive to temperature and indium thickness. Electrically almost no difference was observed between the hall bar and van der pauw type samples. Both conduct by thermionic emission revealing an activation energy that become deeper with increased indium thickness. Furthermore, the room temperature frequency dependent impedance, conductance and capacitance were measured in the frequency range of 10-1800 MHz. Remarkable shift in the frequency value of maximum conductance was observed upon viii indium layer enhancement. The theoretical analysis and computer simulations that targeted the exploration of the physics of resonance phenomena which is accompanied with by negative capacitance phenomena have shown that, the Au/MoO3/C device is of tunneling diode type in which the current conduction covert from tunneling to correlated barrier hoping at 300 MHz. This type of study is expected to open the doors for efficiently utilize the MoO3 films in optoelectronic technology with less resistance and best optoelectronic achievement