Fig. 1. Schematic diagram and working mechanism of the broadband near infrared hot electrons photodetector with multi-layer structure

Fig. 2. Reflection and absorption spectra of various DBR structures and devices

Fig. 3. Energy distributed curves of the generation hot electrons with 1000 nm and 1800 nm incident light

Fig. 4. Generation rate and transport probability distributed in the TiN thin films and corresponding device response spectra

Fig. 5. Absorption spectra of TiN thin films and device response spectra with various DBR period

Fig. 6. Absorption spectra of TiN thin films and device responsivity with different DBR central wavelengths

Fig. 7. Absorption spectra of TiN thin films and device responsivity spectra with various TiN thicknesses

Fig. 8. Absorption spectra of TiN thin films and device responsivity spectra as a function of MgF anti-reflectance layer thickness（the thickness of TiN thin films is 10 nm）

Fig. 9. Absorption spectra of TiN thin films with different incident angles for the TE polarization and TM polarization

Fig. 10. Device responsivity as a function of incident angles with the TE polarization and TM polarization