Alloy Thin Films by MultiTarget Sputtering Karla L

Alloy Thin Films by Multi-Target Sputtering Karla L. Perez MSE/REU Final Presentation Adv. Prof. King and Prof. Dayananda August 5, 2004

Overview • • Introduction Research Project Processing Measuring Film Thickness – Optical Microscope – AFM • Alloy Thin Film Deposition – Composition • Conclusion

Application of Thin Films • Antireflection coatings for camera lenses • Optical filters for communication • Decorative coatings on plastics • Silicon chips • Metallic coatings • To provide insulating layers between conductors

Research Project • • The main goal is to create alloy thin films with uniform composition and thickness Study the compositions of pure metal thin films and their thickness Pure metal components to be used: Ag, Cu, Ta, Mo, Ni, Fe, Ti Design a system which will enable us to manage the composition and geometry of the alloy thin films

Processing • Sputtering It is a type of Physical Vapor Deposition. It is carried out at high vacuum in a chamber connected to a high voltage DC supply. Argon gas is pumped into the chamber and creates argon plasma. The Argon plasma is directed to the target and its atoms are vaporized. The vaporized material is then deposited on the substrate.

Measuring Film Thickness • Optical Microscope – Differential Interference Contrast (DIC) Ag 20 min 4 cm

Measuring Film Thickness Optical Microscope Cu 10 min 4 cm Ag 20 min 4 cm

Measuring Film Thickness Optical Microscope Ag 10 min 4 cm Ag 20 min 4 cm

Measuring Film Thickness • Atomic Force Microscope (AFM) – Tapping mode: Measures the topography by tapping the surface with an oscillating tip. This eliminates the shear forces which can damage soft samples and reduce image resolution.

Measuring Film Thickness

Measuring Film Thickness AFM Ag 20 min 2 cm

Measuring Film Thickness AFM Mo 30 min 2 cm

Measuring Film Thickness AFM Cu 30 min 2 cm

Ag 30 min 2 cm 52. 40 14. 19

Alloy Thin Film Deposition • Deposit alloy thin films using a sputter coater with a Copper-Silver target

Composition of Ag-Cu Thin Film 92. 7% 50. 3% 7. 3% Position on slide

Composition of Ag-Cu Thin Film 95. 6% 50. 3% 4. 4% Position on slide

Conclusion • The thickness of the film varies according to their position relative to the target. • Films deposited are thicker in the middle. • Deposited one alloy thin film • The same composition gradients of silver and copper do not occur in the middle of the film.

Acknowledgements • • Prof. King Prof. Dayananda Prof. Kvam NSF Grant

Questions? ? ? Thank you!!!