Photodetector with artificial atoms of silicon

Abstract

The authors demonstrate a potential application of quantum dots for the detection of photons, showing that the Coulomb interaction resulting from the capture of photoexcited carriers by quantum dots produces a detectable change in the source-drain resistance of the transistor. This quantum effect is more pronounced with higher illumination, displaying staircase quantum steps with ΔV=4mV on the I-V characteristics at room temperature, implying that the photocurrent is increased as the light intensity is increased. The responsitivity of device is R∼3.98×106A∕W for Vd=0.18V, and external quantum efficiency is more than 8.6%.

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

“…Research on silicon nanocrystal ͑Si NC͒ photodetectors ͑PDs͒ has been actively conducted [1][2][3][4] because Si NCs have shown intriguing properties such as bandgap control with nanocrystal size, 5-7 very fast optical transition, 8 and multiple carrier generation. 9 Recently, we showed that the photocurrent onset energy of Si NC PD redshifts with increasing Si NC size, 10 which opens up the possibility of developing wavelength-sensitive PDs for silicon-based image sensors.…”

Size-dependent photocurrent of photodetectors with silicon nanocrystals

“…5 These properties have made Si NCs useful in various devices, such as light-emitting devices, 6-8 solar cells, [9][10][11] and photodetectors. [12][13][14][15][16] Recently, the sizedependent properties of Si NCs were studied to realize silicon-based wavelength-sensitive photodetectors without using color filters, 12 because it has been shown that the absorption onset energy of silicon can be controlled by using quantum confinement effects in Si NCs. 2 Although a few reports have demonstrated photodetectors using Si NCs embedded in silicon oxide 13,14 and silicon nitride, 15 there has been no report on the relationship between the size of Si NCs and the photocurrent of Si NC photodetectors.…”

“…[12][13][14][15][16] Recently, the sizedependent properties of Si NCs were studied to realize silicon-based wavelength-sensitive photodetectors without using color filters, 12 because it has been shown that the absorption onset energy of silicon can be controlled by using quantum confinement effects in Si NCs. 2 Although a few reports have demonstrated photodetectors using Si NCs embedded in silicon oxide 13,14 and silicon nitride, 15 there has been no report on the relationship between the size of Si NCs and the photocurrent of Si NC photodetectors. Moreover, a clear relationship between the absorption in Si NCs and the photocurrent of Si NC photodetectors has never been reported because most studies 12,14-16 have been performed with diode or transistor structures, where the photocurrent is heavily affected by the current from silicon wafers.…”

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

“…The cadmium-free nature of Si-NCs makes them prime candidates for solid-state and backlighting industries [4]. Photodetectors have been fabricated based on Si-NCs and bandgap engineered with adjustments in NC size [5][6][7][8]. Kim et al made a significant step towards the development of new silicon image sensors by showing that it is possible to develop wavelength-sensitive photodetectors by adjusting the Si-NC size [9].…”