Initial Effects of Substrate Heating in Thin Film Depositions

1
Initial Effects of Substrate Heating in Thin Film
Depositions

• Name John Magulick
• Level Sophomore
• Number of Semesters Participated 2
• Date of Submission 05/07/04
• Advisor Dr. Schlaf
• Department Electrical Engineering

2
Heater Construction

• Built on resistive heating design
• Copper stage with integrated, insulated Ta wire
  passages
• Thermocouple attachment
• Connected to electrical feedthrough, remote power
  supply and parallel/integral/differential (PID)
  controller
• Schematic drawing of heater shown at left

3
Initial Effects of Heating

• Highly Ordered Pyrolitic Graphite (HOPG) heated
  to 60C and deposited with PolyAdenosine (Poly
  rA)
• X-ray Photoemission Spectroscopy (XPS),
  Ultraviolet Photoemission Spectroscopy (UPS)
  measurements performed
• Comparison between heated and ambient survey
  spectra (top) reveals peak shifts which imply
  chemical changes
• Secondary edge measurements (bottom) reveals
  stabilized charging not found on ambient
  substrates which also implies chemical changes.

4
Initial Effects of Heating

• Sodium (component of Poly rA solution shown left)
  also present on heated substrates, but is absent
  from ambient ones
• Preliminary AFM analysis shows the absence of
  ring structures on heated substrate (bottom)
  thought to be caused by water droplets usually
  found on ambient substrates (top)

Data implies water does not bind to heated
substrate and allows more distributed deposition