In-Plane Selective Area Epitaxy of InAsSb Nanowire Networks for High-Performance Scalable Infrared Photodetectors

CMOS-compatible III-V semiconductor nanowire infrared photodetectors have attracted extensive research interest in various fields such as Si photonics and gas sensors. However, the traditional vertical configuration of nanowires limits their applications at the circuit level. Here, an in-plane selective area epitaxy route is developed to grow large-scale InAsSb nanowire networks on patterned Si substrates. By precisely tuning the growth parameters, the well-aligned InAsSb nanowire networks with good selectivity are successfully achieved. Detailed structural studies confirm that there is a sharp interface between the InAsSb nanowire and the substrate. On the basis of optoelectronic measurements, it is confirmed that the fabricated InAsSb nanowire network photodetectors exhibit a low dark current density (<= 2 mA cm-2) and a wide spectral response (1200-1650 nm) at room temperature, covering the important telecommunication bands. Moreover, these devices present a high on-off ratio, large responsivity, high detectivity, and rapid response speed at zero bias voltage. At the illumination wavelength of 1200 nm, the on-off ratio, responsivity, detectivity, and response time of a double nanowire networks photodetector can reach 2680, 286.9 mA W-1, 1.4 x 1010 Jones and 75.3 mu s, respectively. This work offers a straightforward approach to in situ fabricating high-performance scalable nanowire photodetectors. In-plane selective area epitaxy is a promising technique for achieving large-scale nanowire photodetectors. Here it is experimentally demonstrated that the high-performance InAsSb nanowire network photodetectors have a low dark current density (<= 2 mA cm-2) and a wide spectral response (1200-1650 nm) at room temperature. The stable and rapid photoresponse (75.3 mu s) shows their potential for applications in Si photonics. image