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This research contains a good comparison among technologies of SiNW-FET/InPNW-FET depending on the size of channel and dopants in channel for biosensing application based on the width and dopants for two types of silicon and InP materials in the nanowire channel. A device numerical modelling tool, Silvaco ATLAS is used in step one to design three p-type SiNW-FET/InPNW-FET biosensors with a channel width of 40­­­ nm, 60 nm and 70 nm for these two types of materials and in step two to design three p-type SiNW-FET/InPNW-FET biosensors with different dopants of 0.1×1014 cm-3, 1×1014 cm-3 and 10×1014 cm-3 for these two types of materials. Their sensing process is depended on the alteration in charge density that causes changing in the electric field at the surface of the SiNW-FET/InPNW-FET. The resistivity of the device is changed when a negatively charged biomolecules species has a chemical reaction with the external surface of a P-type SiNW-FET/InPNW-FET. To investigate the effect of different channel width and dopants on the performance of the SiNW-FET/InPNW-FET biosensor, several negatively interface charge densities, QF (-0.1×1012 cm-2, -0.5×1012 cm-2, and -1×1012 cm-2) are introduced on the surface of the SiNW-FET/InPNW-FET channel to represent as the actual target analytics (DNA) captured by the bioreceptor of the biosensor. Based on the results, these negatively QF attract the hole carriers below the surface of p-type nanowire causes to collect carriers in the channel, and make an increase in the device output ID. Increase of the applied negative charge density has allowed for more ID to flow across the channel between drain and source region. The changes of ID with the applied QF are utilized to determine the sensitivities for all designed biosensor with different channel width and channel dopants. The minimum nanowire width of 40 nm with the minimum nanowire dopants of 0.1×1014 cm-3 for the high sensitivity silicon state of 3.6 μA/cm-2 compared to the indium phosphide state of 2.8 μA/cm-2. So the best performance for detecting the desired analyte in the silicon state with the lowest width and dopant to be seen.

In this work, the finite difference time domain (FDTD) method has been utilized to simulate the propagation emission from PbS quantum dots in a hexagonal InP nanowire as a single photon source. The effect of height and radius of the nanowire as well as the location and orientation of the dipole source in the Purcell factor and Quality factor of the nanowire have been investigated. A broadband electric dipole source has been used to model the quantum dot and the effect of shape and radius of PbS quantum dot have been investigated in the final results. The conclusive structure has been optimized to a nanowire with hexagonal cross section with radius of 220nm and height of 10um. The emission peak obtained above 1um with Purcell factor of 4.72 which is in good agreement with cases have been used as single photon source in quantum communication.