Details

Autor(en) / Beteiligte

• Aivaliotis, P
• Zibik, E A
• Wilson, L R
• Cockburn, J W
• Hopkinson, M
• Airey, R J

Titel

Tuning the photoresponse of quantum dot infrared photodetectors across the 8 - 12 μ m atmospheric window via rapid thermal annealing

Ist Teil von

• Applied physics letters, 2007-10, Vol.91 (14), p.143502-143502-3

Ort / Verlag

American Institute of Physics

Erscheinungsjahr

2007

Link zum Volltext

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• We report on wide spectral tunability of narrow-band ( Δ λ ∕ λ ∼ 12 % ) In As ∕ In 0.15 Ga 0.85 As ∕ Ga As quantum dot-in-a-well infrared photodetectors using postgrowth rapid thermal annealing. The well resolved absorption and photocurrent peaks shift from 8 to 11.6 μ m by annealing the devices at 800 ° C for up to 4 min . Upon annealing, the dot confinement potential becomes shallower and the tunneling probability increases, resulting not only in an increased responsivity but also in an increased dark current. The combined effect is to reduce detector detectivity from 1.1 × 10 10 cm Hz 1 ∕ 2 W − 1 at 8 μ m to 3 × 10 9 cm Hz 1 ∕ 2 W − 1 at 11 μ m ( T = 77 K ) . Our results demonstrate that spectral tunability from 8 to 12 μ m can be achieved while maintaining good detector performance.