Drop-casting CsPbBr3 perovskite quantum dots as down-shifting layer enhancing the ultraviolet response of silicon avalanche photodiode

Abstract

Since the absorption zone of ultraviolet (UV) photons with high energy is limited to a few tens of nm on the surface, the high defect density caused by the processes, such as ion implantation, leads to a weak response of the silicon avalanche photodiode (APD) in the ultraviolet band. In this work, the integration of the inorganic perovskite quantum dots (QDs) film by drop-casting as the down-shifting layer is reported for enhancing the UV response of Si APD. The light generated current increases 100% under the 365 nm light emitting diode. The response of the Si APD is improved in the entire ultraviolet band. In particular, the responsivity of APD is increased by 78% at 340 nm with an exceedingly EQE of 92%. In summary, the perovskite QDs film as a down-shifting layer provides an effective and low-cost method to improve the UV response of Si APD.

Complex Dependence of Optoelectronic Properties of Metal Halide Perovskite Thin Films on Quantum Dot Decoration Layers

“…Interactions between perovskite quantum dots (PQDs) and MHP thin films are of strong interest as PQDs with tunable properties can be used to modify and enhance the properties of the films. ,,− While other QDs, such as CdSe and PbS, , have been studied for this purpose, PQDs are unique candidates due to their similarity in properties to MHP films − and have demonstrated the highest potential. PQDs can be integrated into thin film devices in two ways: as a thin decoration layer on top using various deposition techniques such as spin coating, , drop casting, or spray coating or as a dispersed layer within the bulk of the film, using techniques such as sol–gel, co-precipitation, or hydrothermal methods. The use of both all-inorganic and organic–inorganic hybrid PQDs has led to favorable outcomes when incorporated into MHP films.…”

Spectrum converting nanocomposites for sensitive detectors of short-wavelength radiation

“…1b. 3 The nanocomposite coating absorbs UV and converts it into visible/NIR light matching the spectral band of APD responsivity. For this purpose, we used NPs made of lead halide perovskites CsPbX3 (X stands for Cl, Br, and I) and Ln doped compounds that exhibited strong down-converted photoluminescence quantum yield (PLQY).…”

Broad-Spectrum Germanium Photodetector Based on the Ytterbium-Doped Perovskite Nanocrystal Downshifting Effect

“…Compatible with traditional complementary metal oxide semiconductor (CMOS) processes, germanium (Ge) was widely applied in infrared photodetection to meet the needs of optical communication. − Broad-spectrum PDs can obtain more information and have bright application prospects in imaging, remote sensing, gas detection, etc. , Although Ge was capable of fully absorbing ultraviolet–visible (UV–vis) photons, the detection of vertical PIN PDs in the UV–vis band is generally unsatisfactory. This is attributed to the shallow penetration depth of high-energy UV–vis photons (∼10 nm) and a large number of nonradiative recombination centers on the surface introduced by ion implantation, which is called the “dead zone” effect . To fabricate PDs with broad spectral responses, several methods have been proposed.…”

“…In recent years, due to their excellent optoelectronic properties and huge material family system, perovskites have been rapidly developed in many optoelectronic fields, such as photovoltaics, − light emission, − photodetection, , etc . In particular, as a downshifting material, cesium lead halogen (CsPbX 3 ; X = Cl, Br, or I) inorganic perovskite nanocrystals (NCs) have ultrahigh photoluminescence quantum yields (PLQYs), narrower full widths at half-maximum (fwhms), strong and wide UV absorption spectra, tunable photoluminescence (PL) covering the whole visible band, and better stability at the same time. ,, More importantly, the efficient doping of rare earth ions such as ytterbium (Yb) through its unique hot-injection synthesis can broaden its PL to the near-infrared (NIR) range, overlapping with the high-response band of Ge PDs, which provides a theoretical feasibility of fabricating a broad-spectrum PD through the downshifting effect.…”

“…This is attributed to the shallow penetration depth of high-energy UV−vis photons (∼10 nm) and a large number of nonradiative recombination centers on the surface introduced by ion implantation, which is called the "dead zone" effect. 6 To fabricate PDs with broad spectral responses, several methods have been proposed. Through material integration and surface texturing, broad-spectrum PDs have been obtained.…”