1. The Use of Color Indicators for Plasma Enhanced Chemical Vapor Deposition (PECVD) Films Brian Lopas Physics Teacher Navasota High School, Navasota ISD David Staack, Ph.D. Assistant Professor Department of Mechanical Engineering

2. Tsung-Chan “Cliff” Tsai Dr. David Staack

3. 4 th state of matter: ionized gas Made of freely moving electrons and ions Electrically charged particles that respond to electric and magnetic fields Most abundant in the cosmos

4. High temp electrons (20000 ° F) Cold neutral gas – safe to touc h Examples: Natural: Aurora borealisArtificial: Fluorescent lamp Non-Thermal “Cold” Plasma

6. Plasma Enhanced Chemical Vapor Deposition (PECVD) Characteristics: Non-thermal plasma Adhesive to varies surfaces Sterilizer MMA Floating substrate HV Power Supply Helium + - - - - - - - - - - - - - - + + ++ + + + + + + - - - - - Electrode Dielectric tubePlasma jet * * * * * * * * * Film (PMMA)

7. Applications Suitable for live tissues ◦ Polymeric bandage on wounds ◦ Sterilizes

8. Research Question What indicator would be suitable to use under PECVD conditions that would produce a colored film?

9. Equipment Setup Color Indicator

10. Setup Flow Controllers Power Supply Multimeter Substrate (film produced here) Bubbler (MMA)Plasma Jet

11. Experiments Solubility of methyl blue on MMA Stability of methyl blue after plasma ejection Condition of power supply (i.e. voltage, frequency, etc) Functionality of methyl blue on PMMA If it works… Test other color indicators ◦ methyl red ◦ bromothymol blue

12. Data generated Conditions to incorporate color indicator onto the film ◦ Color indicator solvent/concentration ◦ Voltage ◦ Frequency of electricity ◦ Power ◦ Line spectra Color indication

13. Why a color film? pH sensitivity of the film Ability to indicate chemical/metabolic changes or re-infection

14. Summary Use of low temperature plasma to deposit a film Film is functional band-aid: compatible with live tissues, sterilizes and protects from re-infection Film could indicate chemical/metabolic changes or re-infection

15. Acknowledgements Dr. David Staack Tsung-Chan “Cliff” Tsai Texas A&M University Mechanical Engineering Department ◦ Plasma Engineering and Diagnostics Laboratory National Science Foundation (NSF) Enrichment Experience in Engineering (E 3 )

16. Questions?