Papers by Author: Mohamad Rusop

Abstract: This project has been focused on the electrical and optical properties on the effect of Indium doped zinc oxide (ZnO) thin films at different dopant concentrations. These thin films were doped with different In dopant concentrations at 1 at%, 1.5 at%, 2 at%, 3 at%, 4 at% and 5 at% was selected as the parameter to optimize the thin films quality while the annealing temperature is fixed 500 oC. In doped ZnO solutions were deposited onto the glass substrates using sol-gel spin coating method. This project was involved with three phases, which are thin films preparation, deposition and characterization. The thin films were characterized using Current Voltage (I-V) measurement and UV-Vis-NIR spectrophotometer for electrical properties and optical properties. The electrical properties show that the resistivity is the lowest at 4 at% In doping concentration which is 8.27× 10³ Ωcm^-1 The absorption coefficient spectrum obtained from UV-Vis-NIR spectrophotometer measurement shows all films exhibit very low absorption in the visible (400-800nm) and near infrared (NIR) (>800nm) range but exhibit high absorption in the UV range.

Abstract: This project has been focused on the electrical and optical properties respectively on the effect of Tin doped zinc oxide (ZnO) thin films at different dopant concentrations. These thin films were doped with different Sn dopant concentrations at 1 at%, 2 at%, 3 at%, 4 at% and 5 at% was selected as the parameter to optimize the thin films quality while the annealing temperature is fixed 500 oC. Sn doped ZnO solutions were deposited onto the glass substrates using sol-gel spin coating method. This project was involved with three phases, which are thin films preparation, deposition and characterization. The thin films were characterized using Current Voltage (I-V) measurement and ultraviolet-visible-near-infrared (UV-vis-NIR) spectrophotometer (Perkin Elmer Lambda 750) for electrical properties and optical properties. The electrical properties show that the resistivity is the lowest at 4 at% Sn doping concentration with the value 3.08 × 10³ Ωcm^-1. The absorption coefficient spectrum obtained shows all films exhibit very low absorption in the visible (400-800nm) and near infrared (NIR) (>800nm) range but exhibit high absorption in the UV range.

Abstract: This project has been focused on the electrical and optical properties respectively on the effect of Undoped zinc oxide (ZnO) thin films at different annealing temperature which is varied 400 oC, 450 oC, 500 oC, and 550 oC.Undoped ZnO solutions were deposited onto the glass substrates using sol-gel spin coating method. This project was involved with three phases, which are thin films preparation, deposition and characterization. The thin films were characterized using Current Voltage (I-V) measurement and UV-vis-NIR spectrophotometer for electrical properties and optical properties. The electrical properties show that the resistivity is the lowest at 500 oC which its resistivity is 5.36 × 10⁴ Ωcm^-1. The absorption coefficient spectrum obtained from UV-Vis-NIR spectrophotometer measurement shows all films exhibit very low absorption in the visible (400-800nm) and near infrared (NIR) (>800nm) range but exhibit high absorption in the UV range.

Abstract: Tin-doped Zinc Oxide (Sn-doped ZnO) thin films were prepared using zinc nitrate hexahydrate as a starting material by sol-gel immersion method. Then the synthesized samples were characterized by current-voltage (I-V) measurement and FESEM. The Sn doping concentration were varied at 0.2 at.%, 0.4 at.%, 0.6 at.%, 0.8 at.% and 1.0 at.%. The result suggests that the optimum value for Sn doping concentration was 0.8 at.% which exhibited the highest conductive sample with value of 3.00 ×10^-6 S/cm.

Abstract: The binary solid electrolyte Li₂WO₄-LiI with incorporation of nanosize Al₂O₃ was prepared in solid state reaction and characterized by Electrical Impedance Spectroscopy (EIS), Field Emission Scanning Electron Microscopy (FESEM) and Fourier Transform Infrared (FTIR) spectroscopy. Maximum electrical conductivity of 3.35x10^-3 Scm^-1 was recorded for the sample containing 20 wt. % of LiI. Enhancement of electrical conductivity up to 5.8x10^-3Scm^-1 was achieved when 0.5 wt. % of Al₂O₃ was added into the optimum composition of the binary Li₂WO₄-LiI system. Tetrahedral structure of WO₄ that appear at wave number of 906 cm^-1 and 955 cm^-1 in the FTIR spectroscopy confirmed. The existence of conducting pathway for migrations of Li ions in system that contributes to high electrical conductivity.

Abstract: In this paper, the effect of nitrogen gas flow rate on electrical and electronic properties of nitrogen doped amorphous carbon film (a-C:N) by the use of constant +50 V is presented. The flow-rate of nitrogen gas into the furnace was influenced the resistivity as well as conductivity a-C:N film. The resistivity and conductivity of a-C:N films deposited at high nitrogen flow-rate (200 mL/min) produced low resistivity and high conductivity under deposition condition used. The highest resistivity (4.97x10⁷ Ω.cm) and lowest resistivity (2.81x10¹ Ω.cm) is found at 0 mL/min (undoped) and 200 mL/min. The fabricated solar cell device with the configuration of Au/n-C:N/p-Si/Au for undoped (0 mL/min) and nitrogen doped (200 mL/min) achieved efficiency (𝜂) 0.00111% and 0.00120 %, respectively.