The effect of localized surface plasmon on the photocurrent of silicon nanocrystal photodetectors

Abstract

We report on the photocurrent of silicon nanocrystal ͑Si NC͒ photodetectors ͑PDs͒ that contain silver ͑Ag͒ islands. Here, a larger increase in the photocurrent of Si NC PDs was observed with increasing Ag island size. The maximum increase occurred at the wavelength of the Ag surface plasmon resonance and redshifted as the size of the Ag islands increased. As a result, a 97% increase in photocurrent generation was observed and this was attributed mostly to the coupling of Si NC with the localized surface plasmon of the Ag islands in Si NC PDs.

Plasmonics for photovoltaic applications

“…Similar emission has also been reported from CdSe nanocrystals [31]. More recently increased photocurrent was reported from Si nanocrystal photodetectors mainly attributed to the coupling of the nanocrystals to the localised surface plasmons of silver islands [32]. Fig.…”

A plasmonic enhanced photodetector based on silicon nanocrystals obtained through laser ablation

“…The substrate was cleaned through standard cleaning procedures involving acetone, isopropanol and water. 10 nm of Ag thin film was thermally evaporated (VAKSIS-MIDAS) on Si substrate followed by rapid thermal annealing (ATV RTA-SRO-704) of the sample in the presence of N 2 gas at 600 • C for 65 s. This was done in order to form ultra-small Ag-NCs on the Si substrate [44]. This was followed by deposition of 7 nm Al 2 O 3 on the Ag-NCs/Si structure by atomic layer deposition (ALD) for isolation.…”

“…around 490 nm. Ag-NCs absorb light into localized plasmon modes as explained earlier [44]. In the completed device, the Ag-NCs are obtained on Si substrate and are covered by a Al 2 O 3 layer.…”

Dependence of plasmonic enhancement of photocurrent in a‐Si:H on the position and thickness of SiNx spacer layers

“…When the frequency of incident light matches the collective frequency of oscillating electrons at the surfaces of metal nanoparticles, localized surface plasmon resonance (LSPR) characterized by a minimum in transmittance is observed [9,10]. The reduction in transmittance is caused by increased optical extinction defined as the fraction of light absorbed or scattered by the interface and calculated as 1-T-R, where T is the transmittance and R is the reflectance.…”