Anomalous photoresponse of GaN x-ray Schottky detectors

Duboz, Jean-Yves; Beaumont, Bernard; Reverchon, Jean-Luc; Wieck, Andreas D.

doi:doi:10.1063/1.3141818

Volume/Page
Keyword
DOI
Citation
Advanced

Volume: Page/Article:

Search Content Type

article doi:

Citation:

Rational design of high-responsivity detectors of terahertz radiation based on distributed self-mixing in silicon field-effect transistors

In search of novel detectors of electromagnetic radiation at terahertz frequencies, field-effect transistors (FETs) have recently gained much attention. The current literature studies them with respect to the excitation of plasma waves in the two-dimensional channel. Circuit aspects have been taken into account only to a limited degree. In this paper, we focus on embedding silicon FETs in a proper circuitry to optimize their responsivity to terahertz radiation. This includes impedance-matched a...

General framework about defect creation at the Si/SiO₂ interface

This paper presents a theoretical framework about interface state creation rate from Si–H bonds at the Si/SiO2 interface. It includes three main ways of bond breaking. In the first case, the bond can be broken, thanks to the bond ground state rising with an electrical field. In two other cases, incident carriers will play the main role either if there are very energetic or very numerous but less energetic. This concept allows one to physically model the reliability of metal oxide semiconductor ...

GaN based materials are believed to be very stable materials, in particular, under irradiation by high energy photons such as x rays. We have studied x-ray detectors based on GaN Schottky diodes. Vertical Schottky diodes were fabricated based on a 20 μm thick undoped GaN layer grown on a conductive GaN substrate. Their photoresponse to near UV light and to x rays was measured. While the response to near UV light was fast and linear as expected, anomalous behaviors were observed under x-ray illumination. The photocurrent increases as the third power of the incident x-ray flux. The photocurrent transient when the x rays is turned on are long and nonexponential (S shape) and strongly differs from the off transient which is fast and exponential. Also, a very strong quenching of the x-ray photoresponse is observed when the detector is simultaneously illuminated with visible light. All of these anomalous behaviors are explained in the frame of a complete model involving traps and tunnel currents. A reasonable quantitative agreement between the model and the experimental data is obtained.

Article Outline

INTRODUCTION
DETECTOR FABRICATION
ELECTRO-OPTICAL CHARACTERIZATION
MODEL
CONCLUSION

RELATED DATABASES

To view database links for this article, you need to log in.

KEYWORDS and PACS

Keywords

gallium compounds, III-V semiconductors, photoconductivity, radiation quenching, Schottky diodes, semiconductor counters, wide band gap semiconductors, X-ray detection, X-ray effects

PACS

29.40.Wk

Solid-state detectors
61.80.Cb

X-ray effects
78.55.Cr

III-V semiconductors
85.30.Kk

Junction diodes
72.40.+w

Photoconduction and photovoltaic effects
07.85.Fv

X- and γ-ray sources, mirrors, gratings, and detectors

ARTICLE DATA

Digital Object Identifier

http://dx.doi.org/10.1063/1.3141818

PUBLICATION DATA

ISSN

0021-8979 (print)

1089-7550 (online)

Publisher

$abstract.society.value is a Member of CrossRef

American Institute of Physics

For access to citing articles, you need to log in.

Figures (7)

Access to article objects (figures, tables, multimedia) requires a subscription; log in to view available files.
(Access to supplementary files, where available, is free for this journal.)