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Published on: February 28, 2019
An intercepted feedback mode for light sensitive spectroscopic measurements in atomic force microscopy.
1Institut für Festkörperelektronik, TU-Wien, Floragasse 7, A-1040 Wien, Austria. juergen.smoliner@tuwien.ac.at
The Review of Scientific Instruments
|November 6, 2007
Summary
A new method temporarily switches off the atomic force microscope laser, preventing stray light interference. This technique enables precise measurements, like Schottky barrier heights on GaAs, for advanced spectroscopy applications.
Area of Science:
- Materials Science
- Nanotechnology
- Physics
Background:
- Atomic Force Microscopes (AFMs) commonly use laser deflection to detect tip motion.
- Intense stray light from the AFM laser disrupts sensitive applications like scanning capacitance and photocurrent spectroscopy.
Purpose of the Study:
- To develop an intercepted feedback method to mitigate stray light interference in AFM.
- To demonstrate the versatility of this method in advanced AFM applications.
Main Methods:
- Implemented a feedback system that allows temporary laser switching.
- The feedback loop continues operating even when the laser is off.
- Utilized the method to measure tip-force dependent Schottky barrier heights.
Main Results:
- Successfully demonstrated a method to temporarily disable the AFM laser without interrupting the feedback loop.
- Enabled accurate measurements in the presence of stray light.
- Measured tip-force dependent Schottky barrier heights on Gallium Arsenide (GaAs) samples.
Conclusions:
- The intercepted feedback method effectively overcomes stray light limitations in AFM.
- This technique enhances the applicability of AFM for sensitive spectroscopic measurements.
- The method proves versatile for various advanced AFM applications, including nanoscale electrical characterization.
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