InP-Based Near Infrared/Extended-Short Wave Infrared Dual-Band Photodetector

• Published in: IEEE photonics technology letters 2020-08, Vol.32 (16), p.1003-1006
• Main Authors: Xie, Zongheng, Deng, Zhuo, Zou, Xinbo, Chen, Baile
• Format: Article
• Language: English
• Subjects: Bias; Crosstalk; Current density; Dark current; Detectors; Dual band; III-V semiconductor materials; Indium gallium arsenide; Indium phosphide; Indium phosphides; In₀.₅₃ Ga₀.₄₇ As PIN; In₀.₅₃ Ga₀.₄₇ As/GaAs₀.₅ Sb₀.₅ T2SL; Lattice matching; Near infrared radiation; NIR/eSWIR photodetector; Optical properties; Photodetectors; Photometers; Room temperature; Sensors; Short wave radiation; Substrates; Superlattices
• ISSN: 1041-1135; 1941-0174
• DOI: 10.1109/LPT.2020.3008853

In this paper, InP based near infrared (NIR) /extended-short wave infrared (eSWIR) dual-band photodetector with In 0.53 Ga 0.47 As and In 0.53 Ga 0.47 As/GaAs 0.5 Sb 0.5 type-II superlattice (T2SL) back-to-back n-i-p/p-i-n structures is demonstrated. Monolithic growth of NIR/eSWIR dual-band photodetector on InP substrate enjoys the benefit of the lattice matched property of InP/InGaAs/GaAsSb material system. Low optical crosstalk (below −10 dB) between the two sub-detector is achieved for wavelength range out of 1690-1750 nm. At room temperature, the device exhibits a dark current density of 1.26\times 10 ^{\mathbf {-5}} A/cm 2 for In 0.53 Ga 0.47 As sub-detector under −0.1 V bias and 3.78\times 10 ^{\mathbf {-2}} A/cm 2 for In 0.53 Ga 0.47 As/GaAs 0.5 Sb 0.5 sub-detector under −1 V bias. The corresponding responsivity and specific detectivity are 0.57 A/W and 2.63\times 10 ^{\mathbf {11}} cm \cdot Hz ^{\mathbf {1/2}} /W at 1640 nm for NIR sub-detector and 0.22 A/W and 1.96\times 10 ^{\mathbf {9}} cm \cdot Hz 1/2 /W at 2~\mu \text{m} for eSWIR sub-detector, respectively. The characterization results show the potential for monolithically growing dual-band SWIR photodetector on InP substrate with low dark current density for SWIR applications.