Title :
Improved solar-blind external quantum efficiency of back-illuminated AlxGa1-xN heterojunction pin photodiodes
Author :
Collins, C.J. ; Chowdhury, U. ; Wong, M.M. ; Yang, B. ; Beck, A.L. ; Dupuis, R.D. ; Campbell, J.C.
Author_Institution :
Dept. of Electr. & Comput. Eng., Texas Univ., Austin, TX, USA
fDate :
7/18/2002 12:00:00 AM
Abstract :
Improved external quantum efficiency for AlxGa1-x N solar-blind pin photodiodes is reported. The zero-bias external quantum efficiency was 53% (Rλ = 0.12 A/W) at 275 nm, and increased to 58% (Rλ = 0.13 A/W) at a reverse bias of 5 V. In addition, the photodiodes exhibited a low dark current density of 8.2 × 10-11 A/cm2 at a reverse bias of 5 V, which resulted in a large differential resistance. The high zero-bias responsivity and large differential resistance combine to yield a high detectivity of D* ~ 3.0 × 1014 cm · Hz1/2 · W-1. These results are attributed to an improved Al0.6Ga0.4N window n-region
Keywords :
III-V semiconductors; aluminium compounds; current density; gallium compounds; p-i-n photodiodes; ultraviolet detectors; wide band gap semiconductors; 275 nm; 5 V; 58 percent; Al0.6Ga0.4N; Al0.6Ga0.4N window n-region; GaN-AlGaN; back-illuminated AlxGa1-xN heterojunction pin photodiodes; detectivity; large differential resistance; low dark current density; reverse bias; solar-blind external quantum efficiency; ultraviolet photon detection; zero-bias external quantum efficiency; zero-bias responsivity;
Journal_Title :
Electronics Letters
DOI :
10.1049/el:20020526
