Fabrication and Characterization of GaN/AlGaN Ultraviolet-Band Heterojunction Photodiodes

Abstract

Results from MOCVD grown n-Al 0.1 Ga 0.9 N/i-GaN/p-GaN UV photodetectors on sapphire substrates are presented. The devices show peak responsivities near 0.2A/W for wavelengths between 352nm and 362nm, and responsivities of less than 10 -3 A/W for wavelengths longer than 375nm and shorter than 342nm. The data is explained in terms of a simple device model.

The effects of LT AlN buffer thickness on the optical properties of AlGaN grown by MOCVD and Al composition inhomogeneity analysis

“…As a promising alternative to Si-based technology, detectors fabricated from III-nitride materials, in particular AlGaN, have been investigated and exhibit excellent potential [1][2][3][4][5]. AlGaN has a wide, direct band gap ranging from 364 to 200 nm, which covers much of the UV spectrum [6]. However, there are some major problems with epitaxial AlGaN, such as slow growth rates, gas-phase parasitic reactions and the presence of defects in large quantities, which are generated during heteroepitaxy and post-epitaxial treatment.…”

Solar-blind AlGaN photodiodes with very low cutoff wavelength

“…[4][5][6] While these detectors have wavelength cutoffs below the visible region, they are not within range to be utilized for certain applications which require strong contrast to the solar background, such as missile threat warning systems. [4][5][6] While these detectors have wavelength cutoffs below the visible region, they are not within range to be utilized for certain applications which require strong contrast to the solar background, such as missile threat warning systems.…”