Scanning probe microscopy and field emission schemes for studying electron emission from polycrystalline diamond

TL;DR

This paper presents a diagrammatic approach to interpret electron emission from polycrystalline diamonds using scanning probe microscopy and field emission schemes, highlighting their complementary roles and potential for detailed surface analysis.

Contribution

It introduces a diagram that rationalizes TUNA observations and proposes TUNA's potential to better understand emission mechanisms by analyzing surface potential barriers.

Findings

TUNA observations can indicate electron emission from grain boundaries.

TUNA and field emission are complementary techniques.

TUNA can measure detailed surface potential barriers.

Abstract

The letter introduces a diagram that rationalizes tunneling atomic force microscopy (TUNA) observations of electron emission from polycrystalline diamonds as described in recent publications. The direct observations of electron emission from grain boundary sites by TUNA could indeed be evidence of electrons originating from grain boundaries under external electric fields. At the same time, from the diagram it follows that TUNA and field emission schemes are complimentary rather than equivalent for results interpretation. It is further proposed that TUNA could provide better insights into emission mechanisms by measuring the detailed structure of the potential barrier on the surface of polycrystalline diamonds.