Cairo University

MTPR Journal


Comparative study of the effect of fs, ps, ns Lasers on the gold, CdS thin films and Mo, TiUsing laser produced plasma (LPP) and pulsed laser deposition (PLD)

M. Atta Khedr1*, Naser Fathi1, Dalia Abdrabou2,5, Atef S. Gadalla1, T. Atwee3, H. M. Abd – Elmonem2, Y. Badr1, Ahmed. A. Khalil 1, H. Sharqawy2,Th. El – Sherbini2, Ali Hussien5 and M. Elnahass4
1-: Laser Science & its Interactions Dept., National Institute of Laser Enhanced Science, Cairo
University, Giza, Egypt.
2-:Physics Department, Faculty of Science, Cairo University, Giza, Egypt.
3-: Physics department, Faculty of Science Damietta, Damietta University.
4 - Physics Department, Faculty of Education, Ain Shams University, Egypt.
5-: Department of Basic Science, Faculty of Engineering, Misr University
for Science and Technology (MUST), 6 October City, Giza, Egypt.

Vol./Issue: 19 , id: 271

Pulsed laser deposition thin films (PLD) is used for preparing gold, and Cadmium Sulphid (CdS) thin films using different laser sources. Three types of lasers with different wavelengths and pulse duration time including thefemtosecond picosecond, and nanosecond (fs, ps, ns) are used for carrying these study. Nd-Yag laser 1064 nm and its double frequency pulses at 532 nm of 8 ns pulse duration time, ps laser pulse at 800 nm wavelength and 200 ps pulse duration time, fs laser pulse at 800 nm wavelength and 40 fs duration time are used. Nd – Yag Laser of 1064 nm is used for preparing CdS thin films under high vacuum 10-6 mbar. These thin films which are deposited by these three types of laser pulses are studied using Atomic Force Microscopy (AFM), Scanning Electron Microscopy (SEM), Energy Dispersive Xray Spectroscopy (EDX) and XRD. The results are showed formation of gold particles for all the three laser pulses, but it was noticed gold thin films in case of femtosecond laser pulse are formed in more symmetric manner than in case of using the ps and ns laser pulses. The effect of increasing of the fs laser power has increased the thin film density. Photoconductivity, XRD of CdS thin films of different thickness and temperature are measured. laser produced plasma using Nd-yag Laser interaction with Titanium Ti and hollow cathode of Molybdenum (Mo) under applied electric field and without are carried out.Electric probe and faraday cup collecting charge are used in plasma diagnostics. The electron Temperature, Electron density, ion velocity distribution function of multi charged ions, ion temperature, ion density are obtained. Laser produced plasma spectroscopy (LPPS) of CdS, Titanium and MO has been measured which gave the high accuracy of the plasma parameters obtained.