In recent years, III–V semiconductor nanowires have been widely investigated for infrared photodetector applications due to their direct and suitable bandgap, unique optical and electrical properties, flexibility in device design and to create heterostructures, and/or grow on a foreign substrate such as Si with more effective strain relaxation compared with planar structures. In particular, vertically aligned and ordered nanowire arrays have emerged as a promising photodetector platform, since their geometry‐related light absorption and carrier transport properties can be tailored to achieve high photodetector performance and new functionalities. In this article, the state‐of‐the‐art progress in the development of various types of infrared photodetectors based on III–V semiconductor nanowire arrays is reviewed. The nanowire synthesis/fabrication methods are introduced briefly at first, followed by discussions on the working principle and device performance of various types of nanowire array‐based photodetectors and their emerging applications. Finally, we analyze the challenges and present the perspectives for the development of future low‐cost, large‐scale, high‐performance nanowire array infrared photodetectors for practical applications.

Antimonide-based ternary III–V nanowires (NWs) allow for a tunable bandgap over a wide range, which is highly interesting for optoelectronics applications, and in particular for infrared photodetection. Here we demonstrate room temperature operation of GaAs _0.56 Sb _0.44 NW infrared photodetectors grown by metal organic vapor phase epitaxy. These GaAs _0.56 Sb _0.44 NWs have uniform axial composition and show p-type conductivity with a peak field-effect mobility of ∼12 cm ² V ⁻¹ s ⁻¹ ). Under light illumination, single GaAs _0.56 Sb _0.44 NW photodetectors exhibited typical photoconductor behavior with an increased photocurrent observed with the increase of temperature owing to thermal activation of carrier trap states. A broadband infrared photoresponse with a long wavelength cutoff at ∼1.66 μ m was obtained at room temperature. At a low operating bias voltage of 0.15 V a responsivity of 2.37 (1.44) A/W with corresponding detectivity of 1.08 × 10 ⁹ (6.55 × 10 ⁸ ) were achieved at the wavelength of 1.3 (1.55) μ m, indicating that ternary GaAs _0.56 Sb _0.44 NWs are promising photodetector candidates for small footprint integrated optical telecommunication systems.