Photoconductance of a submicron oxidized line in surface conductive single crystalline diamond

TL;DR

This paper investigates sub-bandgap photoconductance in hydrogen-terminated diamond with a submicron oxidized line, revealing photoconductive gain due to trapped electrons, advancing understanding of diamond-based optoelectronic devices.

Contribution

It demonstrates sub-bandgap photoconductance in diamond with a patterned oxidized line, highlighting defect-related electron trapping as a key mechanism.

Findings

Photoconductive gain observed across the barrier.

Photogenerated electrons are trapped in defect levels.

The phenomena depend on spatial and energetic characteristics.

Abstract

We report on sub-bandgap optoelectronic phenomena of hydrogen-terminated diamond patterned with a submicron oxidized line. The line acts as an energy barrier for the two-dimensional hole gas located below the hydrogenated diamond surface. A photoconductive gain of the hole conductivity across the barrier is measured for sub-bandgap illumination. The findings are consistent with photogenerated electrons being trapped in defect levels within the barrier. We discuss the spatial and energetic characteristics of the optoelectronic phenomena, as well as possible photocurrent effects.