Electron transport in dodecylamine capped gold nanocluster films using current sensing atomic force microscope...

Area of Science:

• Nanomaterials Science
• Surface Science
• Condensed Matter Physics

Background:

• Gold nanoclusters capped with dodecylamine form rough films on Si(111) substrates.
• Understanding electron transport in such nanostructured films is crucial for electronic applications.

Purpose of the Study:

• To investigate electron transport mechanisms in dodecylamine capped gold nanocluster films.
• To analyze the influence of applied force on electrical properties using current sensing atomic force microscopy.

Main Methods:

• Cataphoretic deposition of gold nanocluster films on Si(111) substrates.
• Current sensing atomic force microscopy (CS-AFM) for topographic and current imaging.
• Force-dependent current-voltage (I-V) measurements on individual nanocluster agglomerates.

Main Results:

• Uniform deposition of gold nanoparticle agglomerates observed, correlating with topographic images.
• Force-dependent threshold voltage in I-V measurements on nanocluster agglomerates.
• Ohmic transport from tip-to-sample and Fowler-Nordheim behavior from sample-to-tip up to 35 nN.
• At higher forces, I-V behavior suggests Schottky/Poole-Frenkel or trapping/detrapping mechanisms.

Conclusions:

• Electron transport in these gold nanocluster films is complex and force-dependent.
• The capping layer and collective charge transport models are important for understanding the observed phenomena.
• Further investigation is needed to precisely identify the mechanisms at higher applied forces.