In this investigation, n-type (100) silicon wafers with a thickness of 600 ± 25 μm and resistance of 0.1-100 μΩ were used to manufacture porous silicon. With the aid of hydrofluoric acid (HF) with a 20% concentration, a current density of 20 mA/cm2, and various experimental drilling times of 5, 15, and 25 minutes with the fixation of other parameters, the photoelectrochemical etching method was successful. The morphology of porous silicon was investigated using scanning electron microscopy (SEM), the XRD- diffraction wide of porous silicon creation with rising apex peaks was confirmed, and (AFM) sponge-like morphology was seen, and the pore diameter grew larger as drilling time rose. In a drilling time of 15 minutes, it is able to quantify both the vibrational and electrical characteristics of the energy band gap using Raman analysis and PL detection. Investigate sample samples' current voltage readings (J-V) at various etching times. Additionally, we discovered devices with a broad wavelength that react to the response in the investigation of the spectrum response PS AL/PS/SI/Al as a photodetector.

No abstract

In this work, palladium nanoparticles (Pd NPs) are synthesized by laser ablation in liquid (PLAL) with wavelength 532[Formula: see text]nm (second harmonic Nd:YAG laser) at different laser energies 360, 660, and 800[Formula: see text]mJ with 200 pulses and an electric coil is used to generate a magnetic field. The resulting nanosolution was deposited on the previously prepared PS. The morphological and structural properties of the prepared substrates (Pd NPs/PS) are calculated by X-ray diffraction (XRD) pattern, Atomic Force Microscope (AFM), and Transmission Electron Microscopy (TEM). Their results showed that with the increase in the energy of laser pulse, the average particle size was 30.73, 22.60, and 18.01[Formula: see text]nm. Optical properties of Photoluminescence (PL) spectra show decrease of energy band gap at 2.38, 2.43, and 2.47[Formula: see text]eV with an increase in the energy. The sensitivity of application samples Pd NPs/PS/Si gas sensors for NO2 and H2S gas was also investigated with respect to temperature variations. Pd NPs/PS/Si gas sensors have a maximum sensitivity of NO2 gas around 52.6% at [Formula: see text]C for sample prepared at energy 360[Formula: see text]mJ but the highest sensitivity of H2S gas was 31.2% at [Formula: see text]C for energy of 660[Formula: see text]mJ. The effects of the operating temperature on reaction and recovery durations for various laser ablation energies are also discussed.

No abstract

In this work, palladium (Pd) nanoparticles (NPs) were synthesized using laser ablation in liquids (LAL) at laser energies of 360, 660, and 800[Formula: see text]mJ and a laser wavelength of 1064[Formula: see text]nm with 200 pulses per shot. The Pd nanoparticle suspension deposited on porous silicon (PS) was investigated. X-ray diffraction (XRD) was used to determine the crystal structure. Field emission-scanning electron microscopy (FE-SEM) revealed the sponge-like structure of the PS and spherical clusters of Pd NPs within it. The optical properties of the prepared solution samples were investigated by testing the absorbance between 250–850[Formula: see text]nm, and energy gap values of [Formula: see text]2.35, 2.56, and 2.75[Formula: see text]eV were calculated for the laser energies 360, 660, and 800[Formula: see text]mJ, respectively. The electrical properties, including [Formula: see text] and [Formula: see text] of the Al/PS/Si/Al and Al/Pd NPs/PS/Si/Al heterojunctions were calculated from [Formula: see text] measurements. The observed enhancement of the fabricated Pd NPs/PS is shown by the broad spectral response in the visible to near-infrared (vis-NIR) range. The increased spectral responsivity due to coating the PS surface with Pd NPs promotes using these nanostructures in photodetectors.