Top- and bottom-illumination of solar-blind AlGaN metal-semiconductor-metal photodetectors

被引：14

作者：

Brendel, Moritz ^{[1
]}

Helbling, Markus ^{[1
]}

Knauer, Arne ^{[1
]}

Einfeldt, Sven ^{[1
]}

Knigge, Andrea ^{[1
]}

Weyers, Markus ^{[1
]}

机构：

[1] Leibniz Inst Hochstfrequenztech, Ferdinand Braun Inst, D-12489 Berlin, Germany

来源：

PHYSICA STATUS SOLIDI A-APPLICATIONS AND MATERIALS SCIENCE | 2015年 / 212卷 / 05期

关键词：

AlGaN; device simulations; metal-semiconductor-metal structures; solar-blind photodetectors; GAN; ULTRAVIOLET; RESPONSIVITY;

D O I：

10.1002/pssa.201431720

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

The spectral performance of solar-blind AlxGa1-xN based metal-semiconductor-metal ultra-violet photodetectors has been measured for top- as well as bottom-illumination at different bias voltages. In the bottom-illumination case the external quantum efficiency spectra can be tuned between a peak or a broad wavelength spectrum by adjusting absorber layer thickness and applied bias voltage. For thin absorber layers the external quantum efficiency is enhanced by a factor of three, reaching 20% quantum efficiency at 20V bias, compared to the front-illumination case. Results of two-dimensional device simulations are well in agreement with the experimental findings. From these simulations it can be concluded, that the different spectral response for top- and bottom-illumination results from the different overlap of optical carrier generation by absorption and carrier transport by the electric field. Spectra of external quantum efficiency of solar-blind metal-semiconductor-metal photodetectors upon top-illumination (dashed) and bottom-illumination (continuous) at 1V, 5V, and 20V bias voltage. The Al0.5Ga0.5N absorber layers of different thickness d(Abs) were grown on AlN/sapphire templates.

引用

页码：1021 / 1028

页数：8

共 41 条

[1] AlGaN Ultraviolet A and Ultraviolet C Photodetectors with Very High Specific Detectivity D [J].