Fig. 1. Characterization of InSe/MoTe₂ heterostructure： （a） Schematic diagram of the InSe/MoTe₂ heterostructure； （b） The AFM image of MoTe₂ flakes. Inset： morphological characteristics of the InSe/MoTe₂ heterojunction； （c） The AFM image of InSe flakes； （d） HRTEM image； （e） EDS of the corresponding elements of the photodetector； （f） Raman spectra of pristine InSe，MoTe₂ and overlapped region.

Fig. 2. Electrical I-V characteristics of the device based on InSe/MoTe₂ heterostructure under non-illumination condition： （a） I_ds-V_ds output characteristics under various back gate voltages； （b） I_ds-V_g transfer curves at various drain voltages.

Fig. 3. （a） Schematic structure of the device under laser irradiation； （b）Photo-response of the I_ds-V_ds output characteristics with different incident light power under 365 nm illumination （V_g = 0 V） ；（c） Photo-response of the I_ds-V_g transfer characteristics with different incident light power under 365 nm illumination （V_ds = 6 V） ；（d） The I_ph as a function of incident light power at V_ds = 6 V

Fig. 4. （a） Responsivity as a function of the gate voltage under different incident light powers （V_ds=6 V）； （b） Detectivity as a function of incident light power density （V_ds=6 V，V_g=-15 V） ； （c） EQE as a function of the gate voltage under different incident light powers （V_ds=6 V） ； （d） Noise equivalent power （NEP） as a function of illumination power intensity （V_g = -15 V，V_ds=6 V）； （e） Time-dependent photocurrent response under switched-on/off light irradiation with different power intensities at V_ds=1 V，V_g=0 V； （f） The rise and decay times of the photocurrent under the power intensity of 16.75 mW/cm² at V_ds =1 V

Fig. 5. （a） Photo-response of the I_ds-V_ds output characteristics （V_g = 0 V）； （b） Photo-response of the I_ds-V_g transfer characteristics （V_ds = 6 V） under different incident light wavelengths.

Fig. 6. （a） Time-dependent photocurrent response with different wavelengths at V_ds = 2 V； （b） 2D plot of responsivity as a function of incident light wavelength and gate voltage at V_ds=6 V； （c） D^* and EQE as a function of incident light wavelength at V_ds=6 V and V_g=0 V of InSe/MoTe₂ heterojunction_{photodetector； （d） Dependence of NEP on the different wavelengths at Vds = 6 V and Vg = 0 V}