▎ 摘　　要

In the past decade, graphene-based near infrared photodetectors (NIR PDs) have attracted attention for their high response speed and high responsivity. As a promising graphene-based nanostructure, the InGaAs/Al2O3/gra-phene device has been proven to have important applications in the detection of the near infrared light. The monolayer graphene and a thin Al2O3 layer could improve the device performance. However, the device degraded the current-voltage (I-V) characteristics. To enhance the resistance of this Schottky nanostructure NIR PD to the irreversible degradation, a layer of p-InP under the SiNx is expected to reduce the defects and enhance the absorption of NIR light. In this work, the Schottky nanostructure NIR PD with the InP layer has a high detectivity of 2.3(13) cm Hz(1/2) W-1, a high response speed of 557 ns/3.22 mu s, and a high responsivity of 11.23 A/W at-1.5 V and 1.32 A/W at 0 V to 1550 nm infrared light, which is even larger than that of the metal -oxidation-semiconductor (MOS) structure. The wavelength-responsivity (lambda-R) characteristics measured by different infrared lasers ranging from 808 nm to 1870 nm indicated a wide response spectrum. Moreover, the phenomenon of the reverse photocurrent was observed and analyzed.