This to demonstrate the laser ablation of hard materials to form a thin film for optical sensors. The work was done at DIllard University , New Orleans LA by Professor Abdalla Darwish. any comment e-mail adarwish@bellsouth.net.

1. Abdalla Darwish Dillard University, Physics and Engineering Department, New Orleans, LA 70122 Laser Matter Research Lab , Kenner, LA 70065 University of New Orleans, New Orleans, LA 70122

6. 1.The target material is ablated by a KrF excimer laser or Nd:YAG laser. 2. The ejected material forms a plasma plume and expands across to the substrate where it is deposited as a film. 3. The substrate is heated by a raster-scanned CO 2 laser. 4. A background gas is used to control the plume stoichiometry and dynamics.

19. Some defects on the thin film due to PLD process

20. SEM of the thin film with 100 mJ and 150 mJ energy pulse before using the thin film

21. SEM of the thin film after 10 hours and 30 hours of usages

22. X-section of the thin film

24. Laser in The optical sensor Beam expander Acoustic wave Beam collector Beam expander

25. Diffraction pattern without acoustic wave, T=85 F Diffraction pattern with acoustic wave, T= 85F Diffraction pattern with acoustic wave T=65 F Diffraction pattern with acoustic wave , T=40 F

26. Diffraction pattern with acoustic wave , T=105 F

28. Diffraction pattern with acoustic wave after 65 hours of usages and exposure to many different temperature over the period of one year