Creating NanoPatterns through Atomic Force Microscopy

1
Creating Nano-Patterns through Atomic Force
Microscopy

• Name Suzie Harvey
• Level Senior
• Number of Semesters Participated 4
• Date of Submission 12/17/04
• Advisor Dr. Rudy Schlaf
• Department Electrical Engineering

2
Introduction

• Nanolithography
• The process of creating nano-sized patterns on
  a surface.
• In our experiments the AFM was used to create
  nano-oxide patterns on silicon
• AFM Controller
• The AFM has the ability to image and pattern a
  surface through the use of a cantilever and laser
  feedback mechanism.
• The movement of the cantilever is directed by the
  AFMs control software.

3
Methodology

• Oxidation
• Voltage is applied to tip while is passes over
  sample surface.
• Oxygen bonds attach to surface
• Oxide grows on surface, creating nano-pattern.
• PMMA Exposure
• PMMA is sputtered onto a silicon wafer, and
  placed into AFM.
• Voltage is applied to tip while is passes over
  surface, exposing the PMMA.
• MIBK/IPA solution removes only exposed areas,
  leaving an etched pattern.
• Dip-Pen
• Tip is dipped into Au solution, dried and placed
  into AFM.
• Small voltage is applied to tip, transferring Au
  particles onto sample surface to form a pattern.

4
Results

• Dip-Pen Lithography
• Au deposits on Titanium
• Tip Voltage 5V
• Write Speed 0.5m/s
• Setpoint Factor .02

Oxidation

• Oxidation of Silicon
• Tip Voltage 10V
• Write Speed 0.5µm/s
• Setpoint Factor .02
• Oxide thickness 5nm.
• Dimensions of pattern 10µm10µm

• Oxidation of Titanium
• Tip Voltage 18.33V
• Write Speed 0.5µm/s
• Setpoint Factor .02
• Oxide thickness 50nm.
• Dimensions of pattern 10µm10µm