Abstract-Graphene-based materials in the infrared and terahertz detector families: a tutorial

A. Rogalski

https://www.osapublishing.org/aop/abstract.cfm?uri=aop-11-2-314

The extraordinary electronic and two-dimensional materials make them promising candidates to replace traditional photodetectors in infrared and terahertz spectral ranges. This paper reviews the latest achievements in graphene detectors in competition with traditional commercially dominated ones in different applications. It is shown that the performance of graphene-based infrared and terahertz detectors is lower in comparison with those detectors existing on the global market. The high sensitivity of hybrid photodetectors does not coincide with a fast response time, which limits real detector functions. The most effective single graphene detectors operated at room temperature are terahertz detectors, which utilize plasma rectification phenomena in field effect transistors. The challenges facing the development of focal-plane arrays in the future are also considered. Special attention is directed toward the main trends in the development of arrays in the near future—an increase in the pixel count to above 108${10}^8$ pixels, with pixel size decreasing to about 5 μm for both cooled and uncooled long-wavelength infrared arrays. To date, these questions have not been considered in literature devoted to graphene-based infrared and terahertz detectors.

© 2019 Optical Society of America

Abstract-Semiconductor detectors and focal plane arrays for far-infrared imaging

• A. Rogalski

http://link.springer.com/article/10.2478/s11772-013-0110-x

The detection of far-infrared (far-IR) and sub-mm-wave radiation is resistant to the commonly employed techniques in the neighbouring microwave and IR frequency bands. In this wavelength detection range the use of solid state detectors has been hampered for the reasons of transit time of charge carriers being larger than the time of one oscillation period of radiation. Also the energy of radiation quanta is substantially smaller than the thermal energy at room temperature and even liquid nitrogen temperature. The realization of terahertz (THz) emitters and receivers is a challenge because the frequencies are too high for conventional electronics and the photon energies are too small for classical optics.

Development of semiconductor focal plane arrays started in seventies last century and has revolutionized imaging systems in the next decades. This paper presents progress in far-IR and sub-mm-wave semiconductor detector technology of focal plane arrays during the past twenty years. Special attention is given on recent progress in the detector technologies for real-time uncooled THz focal plane arrays such as Schottky barrier arrays, field-effect transistor detectors, and microbolometers. Also cryogenically cooled silicon and germanium extrinsic photoconductor arrays, and semiconductor bolometer arrays are considered.