[Show abstract][Hide abstract] ABSTRACT: A quantum dot based infrared photodetector (QDIP) with very high detectivity of 3 × 10 11 cm Hz 1/2/W at 78 K was studied. The dark current of a 250-μm-diameter QDIP for various temperatures in the range 78 K to room temperature was shown. The dark noise current was measured with fast fourier transform (FFT) spectrum analyzer and a low-noise current preamplifier. The results show that the high detectivity seen at 1.4 V corresponds to photoresponse peaks at 9.3 and 8.7 μm for positive and negative bias.
[Show abstract][Hide abstract] ABSTRACT: This paper reviews recent progresses in developing self-assembled InAs/GaAs quantum dots based infrared photodetectors, especially, with n-i(QDs)-n configuration. These significant progresses indicate a realistic hope that QDIPs can be exploited for mid-infrared imaging application.
Infrared and Millimeter Waves, 2004 and 12th International Conference on Terahertz Electronics, 2004. Conference Digest of the 2004 Joint 29th International Conference on; 01/2004
[Show abstract][Hide abstract] ABSTRACT: We report a series of InAs quantum dots infrared photodetectors. By using InGaAs cap layers and InAIGaAs lateral potential confinement layers, the peak absorption can be manipulated in from ∼5.6 μm to ∼9 μm.
Compound Semiconductors: Post-Conference Proceedings, 2003 International Symposium on; 09/2003
[Show abstract][Hide abstract] ABSTRACT: The temperature dependence of the orientation of intraband-transition-induced dipoles in self-assembled InAs/GaAs(001) quantum dots (QDs) embedded in n-i(QDs)-n configuration was reported.
Compound Semiconductors, 2003. International Symposium on; 09/2003
[Show abstract][Hide abstract] ABSTRACT: This paper surveys recent work in several photodetector areas including
high-speed, low-noise avalanche photodiodes, solar-blind ultra-violet
PIN photodiodes, and quantum dot infrared photodetectors (QDIPs).
Proceedings of SPIE - The International Society for Optical Engineering 07/2003; DOI:10.1117/12.482483 · 0.20 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: An InAs/AlGaAs quantum-dot infrared photodetector based on bound-to-bound intraband transitions in undoped InAs quantum dots is reported. AlGaAs blocking layers were employed to achieve low dark current. The photoresponse peaked at 6.2 μm. At 77 K and -0.7 V bias, the responsivity was 14 mA/W and the detectivity, D*, was 10<sup>10</sup> cm·Hz<sup>1</sup>2//W.
[Show abstract][Hide abstract] ABSTRACT: Manipulation and control of the electronic structure of quantum dots (QDs) is of central importance to their applications in electronics and optoelectronics. Such tuning is typically carried out by varying the QD average size and shape, or the capping layer, or annealing QDs thermally. Most these approaches do not allow selective tuning some QD states but not others. In this report, we introduce and demonstrate a mean of achieving selective tuning of energy levels through the use of a thin layer, called here the lateral potential confinement layer (LPCL), positioned at the bottom, upper, or top regions of the QDs.
Molecular Beam Epitaxy, 2002 International Conference on; 02/2002
Journal of vacuum science & technology. B, Microelectronics and nanometer structures: processing, measurement, and phenomena: an official journal of the American Vacuum Society 01/2002; 20(3). DOI:10.1116/1.1463695 · 1.46 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: We report on normal-incidence single and dual-wavelength intraband infrared photodetectors (with contacts in the vertical configuration) based on epitaxial InAs/InAlGaAs quantum dots.
Lasers and Electro-Optics Society, 2002. LEOS 2002. The 15th Annual Meeting of the IEEE; 01/2002