Papers Published

1. Chakrabarti, S. and Stiff-Roberts, A.D. and Bhattacharya, P. and Kennerly, S.W., Heterostructures for achieving large responsivity in InAs/GaAs quantum dot infrared photodetectors, Journal of Vacuum Science and Technology B: Microelectronics and Nanometer Structures, vol. 22 no. 3 (2004), pp. 1499 - 1502 [1.1755709] .
   (last updated on 2007/04/16)

   Abstract:
   The fabrication of two different quantum dot infrared photodetectors (QDIP) for achieving large responsivity in InAs/GaAs QDIP at higher operating temperature was reported. A distinct increase in the responsivity was measured at a very high operating temperature in the case of the first heterostructure which was a device with 70 quantum dot layers. The second device had ten layers of InAs quantum dots embedded in an AlAs/GaAs superlattice in order to take advantage of the resulting increased quantum dot intensity. Subsequent large dot density and increased carrier confinement resulted in extremely high responsivity of 2.5 A/W and high conversion efficiency of 70% in multiwafer infrared QDIPs at a temperature of 78 K.

   Keywords:
   Semiconducting indium compounds;Semiconducting gallium arsenide;Semiconductor quantum dots;Photodetectors;Superlattices;Photocurrents;Photoluminescence;Semiconductor doping;Transmission electron microscopy;Molecular beam epitaxy;Atomic force microscopy;