Detection of High Energy Ionizing Radiation using Deeply Depleted Graphene-Oxide-Semiconductor Junctions

TL;DR

This paper demonstrates a graphene-oxide-semiconductor junction detector capable of sensing high-energy ionizing radiation at room temperature, showing robustness and no significant damage after irradiation with 20 MeV Si4+ ions.

Contribution

The study introduces a novel deeply depleted graphene-oxide-semiconductor detector architecture for ionizing radiation sensing, leveraging graphene's properties for improved charge detection.

Findings

Successful detection of 20 MeV Si4+ ions over a range of doses

Device maintained functionality with no substantive degradation after irradiation

Post-irradiation analysis shows no discernible damage to graphene

Abstract

Graphene's linear bandstructure and two-dimensional density of states provide an implicit advantage for sensing charge. Here, these advantages are leveraged in a deeply depleted graphene-oxide-semiconductor (D2GOS) junction detector architecture to sense carriers created by ionizing radiation. Specifically, the room temperature response of the silicon-based D2GOS junction is analyzed during irradiation with 20 MeV Si4+ ions. Detection was demonstrated for doses ranging from 12-1200 ions with device functionality maintained with no substantive degradation. To understand the device response, D2GOS pixels were characterized post-irradiation via a combination of electrical characterization, Raman spectroscopy, and photocurrent mapping. This combined characterization methodology underscores the lack of discernible damage caused by irradiation to the graphene while highlighting the nature of interactions between the incident ions and the silicon absorber.