Enhancing the performance of an InAsSb/InAlSb-based pBn photodetector for early detection of a biomarker of bone marrow cancer: a proposed and simulated approach with extended-midwave response and step-graded barrier design

In this study, we introduce a new extended-mid-wavelength InAsSb-based pBn architecture infrared barrier photodetector with an InAlSb compositional step-graded barrier (SGB), referred to as SGB-pBn-PD, designed specifically to detect a biomarker of bone marrow cancer. Our device outperforms conventional design by replacing the compositional uniform barrier with a step-graded barrier, resulting in improved alignment of the valence band in the barrier and absorber interface, and reduced dark current density via suppression of the Shockley –Read–Hall process. Our simulations show that the dark current density of this detector reaches ~ 2.07 × 10–7 A/cm2 under -400 mV at 150 K. Furthermore, our optical examination reveals that the detector's response peak is around Amide I band, making it highly capable of detecting the Amide I band, a known as biomarkers of bone marrow cancer, particularly acute lymphoblastic leukemia. At -500 mV, the detector's merit criteria, including current responsivity, shot-thermal-limited specific detectivity and noise equivalent power are  ~ 1.9 A/W, ~ 2.77 × 1012 cmHz1/2/W and  ~ 3.60 × 10–13 W/Hz1/2, respectively. Results indicate that our proposed detector performs exceptionally well and has distinct electrical and optical properties, making it an excellent candidate for optical diagnostics in modern infrared biosensor applications.
Source: Sensing and Imaging - Category: Biomedical Engineering Source Type: research