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Silicon-based conventional photodetectors have always been a vital part of many electronic and optoelectronic circuits because of their low fabrication cost, high device performance, and simple configuration. However, due to the relatively poor light–matter interaction and narrow bandgap in Si, these photodetectors generally suffer from a certain compromise in their photoresponsivity as well as broadband photoresponse. Here, a novel approach of coupling reduced-graphene oxide (rGO) decorated $\beta $ -In2S3 with Si has been demonstrated. $\beta $ -In2S3 thin film has been grown by a direct and transfer-free method on Si substrate and rGO has been drop-casted on $\beta $ -In2S3. This introduction of a double-heterojunction architecture results in a photoresponsivity of ~30.41 A/W at 625 nm at an applied voltage of −4 V with the response and recovery times of 60 and $40 ~\mu \text{s}$ , respectively, along with a broadband response in the wavelength range of 400–1200 nm. The rGO acts as an efficient hole transporting layer, which readily reduces the recombination of the photogenerated electrons and holes, leading to high photoresponse. These results highlight a simple and cost-effective strategy to construct high-performance broadband photodetectors, which can be useful in future optoelectronic devices. [ABSTRACT FROM AUTHOR]

In this work, an In0.53Ga0.47As/GaAs0.5Sb0.5 type-II superlattice(T2SL) based broadband photodetector with an optical spectrum response ranging from 250 nm to 2400 nm is demonstrated. The photodetector shows a low dark current density of $3.48\times 10^{-4}$ A/cm2 under the bias of −1 V and a specific detectivity (D*) of $1.59\times 10^{10}$ cm $\cdot $ Hz1/2/W at $2 ~\mu \text{m}$ at 293 K. A recessed window on the surface of the top P layer was fabricated to enhance the responsivity of ultraviolet (UV) and visible band. The UV and visible band quantum efficiency (QE) can increase by 40% with the recessed window. [ABSTRACT FROM AUTHOR]

In this paper, a glioblastoma cancer cell biosensor is proposed based on mono-layer graphene/(n-type)Si Schottky junction. Human fibroblast cells are used as a control to study the behavior of the sensor in the presence of healthy cells. It is shown that in the presence of two different glioblastoma cancer cell lines (U87 and T98G) and human fibroblast cells, the photoconductivity of this junction drastically changes under illumination with different wavelengths of light (380 nm to 850 nm). The relative change in photoconductivity of the sensor can not only distinguish the two glioblastoma cancer cell lines, but can also easily differentiate these cancer cells from healthy human fibroblast cells. The proposed sensor is cheap and easily fabricated, and can open a new avenue for detection and differentiation of cancer cells. [ABSTRACT FROM AUTHOR]

This paper reports a photoconductive type (Ag/Cu2SnS3(CTS) QDs/Ag) Vis-NIR photodetector having small channel spacing ($\sim 63.3 \boldsymbol {\mu }\text{m}$) on glass substrate. The low cost solvothermal processed CTS QDs have been used as carrier transporter as well as broad light absorber. The optical parameters of the proposed structure for small illumination power density have been calculated for broad range light illumination wavelengths (650-1100 nm). The responsivity of device was found to be ~37 (mA/W) for visible (730 nm) and ~67 (mA/W) for NIR (940 nm) illumination wavelengths. The sensitivity of the device was observed to be ~2.28 and ~8.2 for 730 and 940 nm illumination wavelengths, respectively, at 5V. The time response of the device have been measured under Vis-NIR illumination and found to be ~0.96 s (rise time) and ~1.29 s (fall time). [ABSTRACT FROM AUTHOR]