Analysis of strain relaxation and dark current minimization in In(Ga)As QDIP with In0.15Ga0.85As/GaAs capping

Quantum dot infrared photodetectors (QDIPs) with different dot materials have been investigated in this study to analyze the optical, structural and electrical behavior. The InAs and In0.5Ga0.5As QDIPs comprise ten vertically-stacked uncoupled quantum dot (QD) layers with In0.15Ga0.85As/GaAs capping, whereas the overgrowth percentage in both the dot materials has been kept similar (~59%). The InGaAs QDIP has a red shifted photoluminescence spectra compared to the InAs QDIP along with a lower full width at half maxima (FWHM) and higher activation energy. This attributes the formation of dots with larger size and higher vertical barrier potential in the InGaAs QDIP heterostructure. The lattice mismatch between the dot and its underlying/capping layer is less in the InGaAs QDs, which has been observed from the HRXRD rocking-curve analysis. The average strain obtained in the InGaAs QD is less compared to the InAs QD. Moreover, a reduced dark current density has been obtained in the InGaAs QDIP compared to the InAs QDIP at room temperature. Both the QDIPs have their spectral response in the mid-infrared range. However, the InGaAs QDIP has peaks with lower FWHM due to minimized dot size dispersion in the structure.

[1]  P. Bhattacharya,et al.  Multi-color infrared sensing with superlattice quantum dot structures and absorption enhancements , 2009, Italian National Conference on Sensors.

[2]  P. Bhattacharya,et al.  Intersubband absorption in annealed InAs/GaAs quantum dots: a case for polarization-sensitive infrared detection , 2003 .

[3]  Pierre Petroff,et al.  Electronic states tuning of InAs self-assembled quantum dots , 1998 .

[4]  D. Ritchie,et al.  Modification of InAs quantum dot structure by the growth of the capping layer , 1998 .

[5]  S. Chakrabarti,et al.  More than one order enhancement in peak detectivity (D*) for quantum dot infrared photodetectors implanted with low energy light ions (H−) , 2013 .

[7]  B. A. Joyce,et al.  Composition of InAs quantum dots on GaAs(001): Direct evidence for (In,Ga)As alloying , 1998 .

[8]  S. Chakrabarti,et al.  Enhancement in multicolor photoresponse for quaternary capped In0.5Ga0.5As/GaAs quantum dot infrared photodetectors implanted with hydrogen ions , 2016 .

[9]  M. S. Skolnick,et al.  Mechanism for improvements of optical properties of 1.3-μm InAs∕GaAs quantum dots by a combined InAlAs–InGaAs cap layer , 2005 .

[10]  Hsien-Shun Wu,et al.  High performance InAs/GaAs quantum dot infrared photodetectors with AlGaAs current blocking layer , 2001 .

[11]  M. S. Skolnick,et al.  Optimizing the growth of 1.3 μm InAs/InGaAs dots-in-a-well structure , 2003 .

[12]  S. Denbaars,et al.  Direct formation of quantum‐sized dots from uniform coherent islands of InGaAs on GaAs surfaces , 1993 .

[13]  S. Chakrabarti,et al.  Thermal stability of the peak emission wavelength in multilayer InAs/GaAs QDs capped with a combination capping of InAlGaAs and GaAs. , 2011, Journal of nanoscience and nanotechnology.

[14]  Joe C. Campbell,et al.  Normal incidence InAs/AlxGa1−xAs quantum dot infrared photodetectors with undoped active region , 2001 .

[15]  Elias Towe,et al.  NORMAL-INCIDENCE INTERSUBBAND (IN, GA)AS/GAAS QUANTUM DOT INFRARED PHOTODETECTORS , 1998 .

[16]  Shiang-Feng Tang,et al.  Near-room-temperature operation of an InAs/GaAs quantum-dot infrared photodetector , 2001 .

[17]  S. Chakrabarti,et al.  A detailed study of the effects of rapid thermal annealing on the luminescence properties of InAs sub-monolayer quantum dots , 2015 .

[18]  S. Fathpour,et al.  Pulsed laser annealing of self-organized InAs/GaAs quantum dots , 2004 .

[19]  C. Honsberg,et al.  Multi-stacked InAs/GaAs quantum dots grown with different growth modes for quantum dot solar cells , 2015 .

[20]  T. Ng,et al.  Electronic confinement in self-assembled quantum dots (SAQD) modeled with a new interfacial capping layer , 2010 .

[21]  C. Stanley,et al.  Stacking of multilayer InAs quantum dots with combination capping of InAlGaAs and high temperature grown GaAs , 2009 .

[22]  Subhananda Chakrabarti,et al.  Characteristics of a tunneling quantum-dot infrared photodetector operating at room temperature , 2005 .

[23]  G. Abstreiter,et al.  Influence of a thin AlAs cap layer on optical properties of self-assembled InAs/GaAs quantum dots , 1999 .

[24]  Pallab Bhattacharya,et al.  Quantum-Dot Optoelectronic Devices , 2007, Proceedings of the IEEE.