This paper presents the fabrication and performance analysis of Zinc Oxide (ZnO) and Ag doped ZnO (SZO) based Metal-Semiconductor-Metal (MSM) ultraviolet (UV) photodetectors. The films were constructed on p-type silicon (Si) (100) substrates by sol-gel technique. Silver (Ag) electrodes were used as a Schottky contact for the fabricated devices. The structural, optical, and electrical properties for the fabricated films were studied and analyzed to show the effects of Ag dopants. With the applied voltage in the range of (-5 to 5 V) under dark condition, the values of the Schottky contact parameters were extracted and compared. Under UV illumination (254 nm) with different optical power levels, the performance parameters were extracted. The SEM image showed a non-uniform distribution of the Ag dopants, these dopants were formed clusters and this clusters acts as traps for the incident light. The saturation current was decreased for the device based on Ag doped ZnO film which enhanced the performance of the device.

With the evolution of electronics today, a MOSFET transistor is useful in many applications such as computers due to several advantages. In this research, an NMOS transistor differential amplifier circuit with passive load that uses a modified Wilson current mirror as a biasing circuit is analyzed, designed and implemented. The width-to-length ratios of transistors are calculated by considering the voltage and current values at the output of the biasing circuit, and parameters such as conduction parameter, base width modulation parameter, and threshold voltage. A MATLAB version 8.1.0.604(R2010a) programming tool is employed for calculations and the simulations are carried out via Multisim 9 software tool. The output resistance obtained for current mirror is. CMRR, output resistance, and power dissipation for differential amplifier circuit are , and , respectively. The results show that the width-to-length ratio, differential gain and common mode rejection ratio are decreased with decreasing applied voltage at the output of the biasing circuit while approximately same values obtained for output resistance and common mode gain. The results show a good agreement between the measured values from simulation and the calculated one from design.

The design and sensitivity aspects of five stages tenth order active bandpass filter suitable for signal processing in electronic circuits are introduced. Simulation process performed is started by evaluating the voltage transfer function of the filter using the nodal approach to the second order activenet work model which represents each stage. The sensitivity analysis with respect to some parameter changes such as resonance frequency and quality factor is treated for proper choice of component values. The computational difficulties in the analog domain manipulations that arises through the cascaded arrangement of the filteris overcome by factorizing the terms in the denominator of the stated voltage transfer function with the aid of MATLAB 7.10.0(R2010a)software program. It was found that the increasing in the quality factor increases the magnitude, phase responses, higher deviation in magnitude sensitivity due to change in resonance frequency and lower frequency range due to change in quality factor. An increasing in the resonance frequency results in a better impulse and step response. The phase sensitivity due to change in resonance frequency shows that an increase in the quality factor gives higher deviation and this deviation is less in the sensitivity due to change in the quality factor. The simulation process of the circuit is done via the introduction of the Multisim software package version 9.0.155, offers good agreements with the results obtained.

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