In this work, the fine structure macro-porous silicon (macroPS) substrate was prepared by photo-electro-chemical etching of n-type silicon wafer. Ultraviolet illumination condition of wavelength 360nm wavelength and intensity of about 100mW/cm2 with etching current density of about 50 mA/cm2 and etching time 5
min was employed. The Hybrid device gold nanoparticles /macroPorous Silicon (AuNPs/macroPS) was fabricated by deposition AuNPs into mPS substrate Via immersion plating process of macroPS in the solution of HAuCl4 with the (10-3M) concentration and 2min immersion time. The characteristics of PS before and after
immersion process were investigated by scanning electron microscopy (SEM), EDS, X-Ray diffraction (XRD), photoluminescence (PL) and Infrared spectroscopy (FTIR). The J-V characteristics of sandwich structure showed that the maximum sensitivity of the AuNPs/macro PS was about (90.5%)for compared with macro-PS substrate. The current-voltage characteristics were performed in primary vacuum with a base pressure of about 0.2mbar and CO2 with 1mbare concentrations.  Significant enhancement was observed in sensitivity of the AuNPs/macroPS hybrid device and temporal response after deposition the AuNPs.