Resonant Cavity–Enhanced Photodiodes for Spectroscopy of C-H Bonds

Bainbridge, Andrew and Craig, Adam and Al-Saymari, Furat and Krier, Anthony and Marshall, Andrew (2021) Resonant Cavity–Enhanced Photodiodes for Spectroscopy of C-H Bonds. physica status solidi (a). ISSN 1862-6300

Full text not available from this repository.

Abstract

Resonant cavity-enhanced photodiodes targeted within the spectral region of absorption by C-H bonds are demonstrated. The 3.0 – 3.3 μm region of the infrared spectrum contains many substances that are useful to measure spectroscopically. However, the measurement of individual substances requires a high spectral specificity, that is achieved by the resonant cavity photodiodes with spectral response widths of <40 nm . Two material systems are investigated for detection at this wavelength range—an InAs absorber on an InAs substrate and an InAsSb absorber lattice-matched to a GaSb substrate. The resonance wavelength of the InAs-based device responds at ≈3.3 μm, closely tuned to an absorption peak of methane to allow precise sensing of this gas. At 300 K a quantum efficiency of 52% is achieved, with a specific detectivity of 2.5×1010 cm√Hz/푊. The InAsSb-based device is sensitive at ≈3.7 μm, but the structure could be tuned to the methane absorption peak. Devices could be simply created to target other substances in the C−H absorption region by altering the layer thicknesses in the structure. Both structures can be used for spectrally specific gas sensing in this region of the infrared.

Item Type:
Journal Article
Journal or Publication Title:
physica status solidi (a)
Subjects:
ID Code:
157453
Deposited By:
Deposited On:
21 Jul 2021 11:15
Refereed?:
Yes
Published?:
Published
Last Modified:
22 Jul 2021 05:24