A large format 1k×1k focal plane array (FPA) is realized using type-II superlattice photodiodes for long wavelength infrared detection. Material growth on a 3 in. GaSb substrate exhibits a 50% cutoff wavelength of 11 μm across the entire wafer. The FPA shows excellent imaging. Noise equivalent temperature differences of 23.6 mK at 81 K and 22.5 mK at 68 K are achieved with an integration time of 0.13 ms, a 300 K background and f/4 optics. We report a dark current density of 3.3×10-4 A cm-2 and differential resistance-area product at zero bias R0A of 166 Ω cm2 at 81 K, and 5.1×10-5 A cm-2 and 1286 Ω cm2, respectively, at 68 K. The quantum efficiency obtained is 78%.
Published in:
Applied Physics Letters
(Volume:97
,
Issue:
19
)
Date of Publication:
Nov 2010
- Page(s):
-
193505
-
193505-3
- ISSN :
-
0003-6951
- Digital Object Identifier :
-
10.1063/1.3514244
- Product Type:
-
Journals & Magazines
- Date of Current Version :
-
11 November 2010
- Issue Date :
-
Nov 2010