Thermomechanical properties of polymer nanolithography using atomic force microscopy

Area of Science:

• Materials Science
• Polymer Science
• Nanotechnology

Background:

• Understanding the temperature-dependent mechanical properties of polymers like polyethylene terephthalate (PET) is crucial for applications involving thermal cycling or elevated temperatures.
• Previous studies have explored PET's mechanical behavior, but a detailed investigation combining nanolithography with controlled heating is less common.

Purpose of the Study:

• To investigate the influence of temperature on the mechanical properties of PET polymers.
• To quantify the changes in groove dimensions and material removal rates under varying thermal conditions.
• To explore the relationship between adhesion force, temperature, and material removal during nanolithography.

Main Methods:

• Utilized atomic force microscope (AFM) nanolithography combined with controlled heating techniques (20-60 °C).
• Measured force-distance curves and adhesion forces to assess mechanical responses.
• Analyzed groove width and wear depth resulting from nanolithography at different temperatures and loads (30-50 nN).

Main Results:

• Groove widths on PET polymers ranged from 14-363 nm at 20-60 °C.
• Wear depth significantly increased with rising heating temperature.
• Material removal volume at 30-60 °C (251.85-2422.66 μm³) was substantially higher than at room temperature (26.60-70.30 μm³).
• Contact forces increased at 9 nN, and hole size was pressure-dependent.

Conclusions:

• Temperature significantly affects the mechanical properties and nanomachining behavior of PET.
• Increased temperature leads to enhanced material removal rates, with implications for surface modification and wear.
• The findings provide insights into the interplay between temperature, adhesion, pressure, and material removal in polymer nanolithography.