Jiuxiang Dai

Light: Science & Applications, Published online: 28 June 2022; doi:10.1038/s41377-022-00885-7

This review outlines the exciting developments in high-performance dielectric metalenses whilst highlighting the challenges of using dielectric metalenses to replace conventional optics in miniature optical systems.

First, the anisotropic lattice structures of 2D materials are illustrated. Second, unique experimental methodologies are discussed for characterizing their anisotropic mechanics. Third, recent processes in anisotropic elastic, fracture, friction, and bending properties of 2D materials are reviewed. Subsequently, unique applications of these anisotropic properties are further highlighted. Finally, prospects for the developments of this field are suggested.

Anisotropic mechanics of van der Waals (vdWs) materials offers opportunity to peel off individual atomic layers, initiating a 2D revolution in the fields of materials science, physics, and chemistry. The elasticity, bending, and fracture strength of most of their 2D derivatives are also orientation-dependent, which not only determines the reliability of devices based on 2D materials but also offers a vast playground for atomic manufacturing with tunable functions. Therefore, a comprehensive understanding of the anisotropic mechanical properties of 2D materials is imminent. In this review, the anisotropic mechanical properties of 2D materials are summarized in attempt to capture the current progress in this field, as well as the route toward their applications. Following a brief discussion of the anisotropic lattice structures of 2D materials, unique experimental methodologies that have been developed to characterize their anisotropic mechanics are discussed. Then, the review pivots on recent processes in anisotropic elastic, fracture, friction, and bending properties of 2D materials. Unique applications of these anisotropic properties, such as mechanical fabrication of atomic precision, as well as anisotropic strain-induced piezoelectric and band modulation, are further highlighted. Finally, besides emphasizing the need for breakthrough in anisotropic mechanics, prospects for the developments of this field are suggested.

Nature, Published online: 29 June 2022; doi:10.1038/d41586-022-01732-w

A simple method for incorporating molecules into the gaps of stacked semimetallic materials through immersion offers an efficient way of filtering electrons, which could be useful for information-storage technologies.

Transient electroluminescence analysis is performed in the quantum dot light-emitting diodes (QLEDs) with a double emission layer structure for in-depth understandings of the transient dynamics of charges and excitons in electrical operation. It enables the extraction of the electron mobility of the quantum-dot film and reveals the chronological processes of electroluminescence in QLEDs.

Abstract

Wide interest in quantum dot (QD) light-emitting diodes (QLEDs) for potential application to display devices and light sources has led to their rapid advancement in device performance. Despite such progress, detailed operation mechanisms of QLEDs, which are necessary for the fundamental understanding and further improvements, have been still uncertain because of the intricate interaction between charges and excitons in electrical operation. In this work, the transient electroluminescence (TREL) signals of dichromatic QLEDs which are purposely designed to consist of two different color-emitting QD layers are analyzed. As a result, not only can the charge injection and exciton recombination processes be visualized but the electron mobility of the QD layer can also be estimated. Furthermore, the effects of Förster resonant energy transfer between two QDs and exciton quenching near the QD layer are quantitatively measured in QLED operation. The authors believe that their results based on TREL analyses will contribute to the understanding and development of high-performance QLEDs.

Nanocarbons have been applied towards the creation of biomaterials for over 15 years. However, clinical biomaterials employing nanocarbons remain elusive mainly due to concerns of safety. With a particular focus on carbon nanotubes, these perspectives aim to summarize the contributions to date on nanocarbon applications and biosafety evaluation in addition to clarifying the future prospects of clinical nanocarbon applications.

Abstract

Over the past 15 years, numerous studies have been conducted on the use of nanocarbons as biomaterials towards such applications as drug delivery systems, cancer therapy, and regenerative medicine. However, the clinical use of nanocarbons remains elusive, primarily due to short- and long-term safety concerns. It is essential that the biosafety of each therapeutic modality be demonstrated in logical and well-conducted experiments. Accordingly, the fundamental techniques for assessing nanocarbon biomaterial safety have become more advanced. Optimal controls are being established, nanocarbon dispersal techniques are being refined, the array of biokinetic evaluation methods has increased, and carcinogenicity examinations under strict conditions have been developed. The medical implementation of nanocarbons as a biomaterial is in sight. With a particular focus on carbon nanotubes, these perspectives aim to summarize the contributions to date on nanocarbon applications and biosafety, introduce the recent achievements in evaluation techniques, and clarify the future prospects and systematic introduction of carbon nanomaterials for clinical use through practical yet sophisticated assessment methods.

The concept of liquid metal (LM) vacuoles with metallic membrane outside and interior solution (S) is proposed and demonstrated for the first time. Such vacuoles can stably exist for a long time through adjusting the solution composition. Besides, the generation, maintenance, and rupture process of the vacuoles are thoroughly interpreted for different substrates.

Abstract

Conventional bubbles are generally made of an outside water film and the interior air, and their formation and rupture involve rich scientific knowledge. An intriguing question is what would happen if the water film and air of such bubbles were replaced by completely different fluids? Here, a high-surface-tension liquid metal-solution bilayer is introduced into the two-phase interface system, and a new conceptual hybrid vacuole consisting of a liquid metal outer membrane and inner solution core is proposed and demonstrated for the first time. Through tuning the filling volume of the liquid metal, various vacuolar structures with diverse interfacial morphologies are constructed. Such vacuoles can maintain long-term stability via adjusting the composition of the solution, which is a mixture of surfactant and alkali. If switching glass substrate to graphite, liquid metal vacuoles would become more robust and exhibit further abundant individual and collective behaviors, which are mainly attributed to the firmer bonding strength between the two-phase interfaces. In addition to interpreting the generation and maintenance mechanisms of the vacuole, different rupture processes are also presented and disclosed. The current findings on the liquid metal-solution hybrid vacuoles are expected to enrich the content of liquid metal interfacial science, and will stimulate further promising applications in the emerging engineering fields.

Liquid phase exfoliation of 1D ternary transition metal chalcogenide Nb₂Pd₃Se₈ is studied. The N-methyl-2-pyrrolidone and dimethylformamide are found to be the best solvents for the exfoliation and stabilization of the Nb₂Pd₃Se₈. The field-effect transistors fabricated by exfoliated Nb₂Pd₃Se₈ exhibit n-type characteristics with an I _on/I _off ratio and field-effect mobility up to ≈10³ and 15 cm² V⁻¹ s⁻¹.

Abstract

Recently, the 1D ternary transition metal chalcogenide Nb₂Pd₃Se₈ has been reported as a promising channel material for the field-effect transistors (FETs) with high performance transport behavior. Its structural characteristic of weak van der Waals (vdW) forces between unit ribbons allows for the isolation of high quality Nb₂Pd₃Se₈ nanowires from the bulk crystal that are similar to typical layered 2D materials. This study reports on the liquid phase exfoliation (LPE) of 1D vdW Nb₂Pd₃Se₈ to predict the optimal solvent in terms of the total surface tension and polar/dispersive component ratio. Among the various test solvents, N-methyl-2-pyrrolidone and dimethylformamide are found to be the best solvents for the exfoliation and stabilization of the Nb₂Pd₃Se₈ nanowires due to their well-matched total surface tensions and polar/dispersive component ratios. Additionally, FETs are fabricated on the LPE-processed Nb₂Pd₃Se₈ nanowires, and the charge transport behavior is characterized at room temperature. The FETs exhibit n-type characteristics with an I _on/I _off ratio and field-effect mobility up to ≈10³ and 15 cm² V⁻¹ s⁻¹. This study on the LPE of novel Nb₂Pd₃Se₈ nanowires is an important step toward various practical applications in nanoelectronics.

Thermoelectrical properties of 5-layer n-type nanolaminates fabricated by physical vapor deposition are studied for the first time. It is found that the Seebeck coefficient of nanolaminates increases by ≈75–125% and the electron thermal conductivity decreases by 65–85% in comparison with the single ultrathin films and the values reported for the nanostructured bulk materials of similar chemical compositions.

Abstract

In this work, simple and cost-effective phyiscal vapor deposition method is applied for deposition of single Bi₂Se₃, Bi_1.925Sn_0.075Se₃, Bi₂Se_2.975Te_0.025 ultrathin films of average thickness 10–12 nm, and for the fabrication of n-type 5-layer nanolaminates. The nanolaminates are composed from alternating doped and undoped ultrathin films. Electrical and thermoelectric properties (Seebeck coefficient, resistivity, electron thermal conductivity, charge carrier concentration, and mobility) of nanolaminates as well as single ultrathin undoped and doped films are studied at room temperature under ambient conditions. Both types of nanolaminates show 75–125% increase of the Seebeck coefficient accompanied by the 65–85% reduction of the electron thermal conductivity in comparison with the nanostructured bulk materials of similar chemical compositions. The mechanisms underlying such improvement of properties of studied nanolaminates in comparison with the nanostructured bulk counterparts are discussed.

An all-nanofiber-based substrateless nanomesh organic transistor is demonstrated for the first time. The device is fully functional under complete bending but shows slight degradation in performance over 10% compression. The nanomesh transistor is integrated with tactile sensors entirely on nanomesh without a conventional substrate and successfully demonstrate its operation on human skin.

Abstract

Nanofiber-based electronic devices have attracted considerable interest owing to their conformal integration on complicated surfaces, flexibility, and sweat permeability. However, building complicated electronics on nanomesh structure has not been successful because of their inferior mechanical properties and processability. This limits their practical application. To achieve system-level device applications, organic field-effect transistors are one of the key components to be integrated with various sensors. Herein, a successful method for fabricating a biocompatible, ultrathin (≈1.5 µm), lightweight (1.85 g m^–2), and mechanically durable all-nanofiber-based organic transistor is reported that can be in conformal contact with curved skin. Furthermore, it is the first development with a substrate-less nanomesh organic field effect transistor. The devices exhibit satisfactory electrical performance, including an on/off value of 3.02 × 10⁴ ± 0.9 × 10⁴, saturation mobility of 0.05 ± 0.02 cm² V^{− 1} s^{− 1}, subthreshold slope of 1.7 ± 0.2 V dec^–1, and threshold voltage of −6 ± 0.5 V. The mechanism of crack initiation is analyzed, via simulation, to understand the deformation of the nanomesh transistors. Furthermore, active matrix integrated tactile sensors entirely on the nanomeshes is successfully demonstrated, indicating their potential applicability in the field of biomedical electronics.

Transient photoconductivity and terahertz spectroscopy are used to determine the long- and short-range sum mobility of PEA₂PbI₄ thin films in this study. For both ranges, a sum mobility of 8 cm² (V s)^–1 is found. This previously unreported mobility independent of the probed length scale indicates “single-crystal”-like behavior in a thin film, which can be advantageous in device fabrication.

Abstract

The use of layered, 2D perovskites can improve the stability of metal halide perovskite thin films and devices. However, the charge carrier transport properties in layered perovskites are still not fully understood. Here, the sum of the electron and hole mobilities (Σμ) in thin films of the 2D perovskite PEA₂PbI₄, through transient electronically contacted nanosecond-to-millisecond photoconductivity measurements, which are sensitive to long-time, long-range (micrometer length scale) transport processes is investigated. After careful analysis, accounting for both early-time recombination and the evolution of the exciton-to-free-carrier population, a long-range mobility of 8.0 +/− 0.6 cm² (V s)^–1, which is ten times greater than the long-range mobility of a comparable 3D material FA_0.9Cs_0.1PbI₃ is determined. These values are compared to ultra-fast transient time-resolved THz photoconductivity measurements, which are sensitive to early-time, shorter-range (tens of nm length scale) mobilities. Mobilities of 8 and 45 cm² (V s)^–1 in the case of the PEA₂PbI₄ and FA_0.9Cs_0.1PbI₃, respectively, are obtained. This previously unreported concurrence between the long-range and short-range mobility in a 2D material indicates that the polycrystalline thin films already have single-crystal-like qualities. Hence, their fundamental charge carrier transport properties should aid device performance.

An amphoteric liganding strategy is developed to simultaneously address In and As dangling bonds on InAs colloidal quantum dot (CQD) surfaces, which provides passivation and charge transport for low-permittivity CQD solids. The resulting photodiodes achieve a response time faster than 2 ns—the fastest photodiode among previously reported CQD photodiodes—combined with an external quantum efficiency of 30% at 940 nm.

Abstract

Colloidal quantum dots (CQDs) are promising materials for infrared (IR) light detection due to their tunable bandgap and their solution processing; however, to date, the time response of CQD IR photodiodes is inferior to that provided by Si and InGaAs. It is reasoned that the high permittivity of II–VI CQDs leads to slow charge extraction due to screening and capacitance, whereas III–Vs—if their surface chemistry can be mastered—offer a low permittivity and thus increase potential for high-speed operation. In initial studies, it is found that the covalent character in indium arsenide (InAs) leads to imbalanced charge transport, the result of unpassivated surfaces, and uncontrolled heavy doping. Surface management using amphoteric ligand coordination is reported, and it is found that the approach addresses simultaneously the In and As surface dangling bonds. The new InAs CQD solids combine high mobility (0.04 cm² V⁻¹ s⁻¹) with a 4× reduction in permittivity compared to PbS CQDs. The resulting photodiodes achieve a response time faster than 2 ns—the fastest photodiode among previously reported CQD photodiodes—combined with an external quantum efficiency (EQE) of 30% at 940 nm.

Nature Materials, Published online: 29 June 2022; doi:10.1038/s41563-022-01299-x

Ultrathin CrSBr, a two-dimensional magnet, has been shown to exhibit very rich magnetic behaviours, from an unexpected magnetic order to optical emissions coupled to its magnetic state. This material has great potential for use in ultra-compact spintronics devices.

Nature Materials, Published online: 29 June 2022; doi:10.1038/s41563-022-01306-1

Excitonic states with hybrid dimensionality in layered silicon diphosphide exhibit interesting features such as linearly dichroic photoluminescence and unusually strong exciton–phonon coupling.

A series of ultra-narrow bandgap non-fullerene acceptors are constructed by central core fluorination and side chain modification, which are applied in both organic solar cells and photodetector devices and achieve good performance. Additionally, the effect of central core fluorination on molecular stacking and optoelectronic properties are systematically studied.

Abstract

Developing non-fullerene acceptors (NFAs) with strong absorption and optical response in near-infrared region (NIR) is an imperative avenue for achieving efficient organic solar cells (OSCs) and NIR organic photodetectors (OPDs). Herein, four ultra-narrow bandgap NFAs with different alkyl side chains and 2D fluorinated or non-fluorinated phenyl substituents using dithienopyrrolecarbazole as electron-rich core are designed and synthesized for photoelectric devices. The effect of 2D central core fluorination on molecular self-assembly and optoelectronic properties is comprehensively explored. Due to the banana-type molecular conformation of these NFAs, they can easily form honeycomb-like 3D network stacking, and the central core fluorination is confirmed that can reduce ππ stacking distance and enhance intermolecular interaction, which result in smaller molecular stacking density. As a result, the 2D fluorinated acceptors based OSCs display more balanced and higher carrier mobilities, contributing to higher fill factor and efficiency. Moreover, the NIR OPD devices based on PTB7-Th:FDTPC-OD exhibit a superior responsivity of >0.4 A W⁻¹ at 880 nm, a low dark current of ≈8 × 10^–11 A, and an excellent specific detectivity (D*) of >2.5 × 10¹¹ Jones. The NIR OPD also demonstrates excellent performance in photo-plethysmography and shows great potential for application in monitoring heart rate.

Nature Communications, Published online: 27 June 2022; doi:10.1038/s41467-022-31256-w

Superconducting diodes, operational at zero magnetic field, can be used in supercomputers. Here, the authors demonstrate prototypes of diodes-with-memory, based on Nb Josephson junctions, with a large and switchable nonreciprocity at zero field.

Nature Reviews Materials, Published online: 27 June 2022; doi:10.1038/s41578-022-00451-y

Mechanically and chemically induced phase transitions in 2D materials offer access to new properties, opening up paths towards future applications. This Review summarizes the theoretical models and experimental processes for inducing phase transformations in 2D materials, especially graphene to 2D diamond, and examines the associated applications.

Nature Electronics, Published online: 27 June 2022; doi:10.1038/s41928-022-00776-0

This Review examines the development of micro-thermoelectric devices, exploring progress in device design, integration and performance, and the potential applications of the technology in cooling, power generation and sensing.

Author(s): Felix Gerken, Thore Posske, Shaul Mukamel, and Michael Thorwart

We develop a microscopic theory for the two-dimensional (2D) spectroscopy of one-dimensional topological superconductors. We consider a ring geometry of an archetypal topological superconductor with periodic boundary conditions, bypassing energy-specific differences caused by topologically protected…

[Phys. Rev. Lett. 129, 017401] Published Mon Jun 27, 2022

The study demonstrates the fabrication of a graphene via contact architecture to electrically connect graphene electrodes (or leads) embedded in van der Waals heterostructures. Graphene via contacts consists of edge and fluorinated graphene electrodes. A vertically integrated complementary inverter based on n- and p-type 2D field-effect transistors is realized by a one-step fabrication process that utilizes the graphene contacts.

Abstract

Two-dimensional (2D) devices and their van der Waals (vdW) heterostructures attract considerable attention owing to their potential for next-generation logic and memory applications. In addition, 2D devices are projected to have high integration capabilities, while maintaining nanoscale thickness. However, the fabrication of 2D devices and their circuits is challenging because of the high precision required to etch and pattern ultrathin 2D materials for integration. Here, the fabrication of a graphene via contact architecture to electrically connect graphene electrodes (or leads) embedded in vdW heterostructures is demonstrated. Graphene via contacts comprising of edge and fluorinated graphene (FG) electrodes are fabricated by successive fluorination and plasma etching processes. A one-step fabrication process that utilizes the graphene contacts is developed for a vertically integrated complementary inverter based on n- and p-type 2D field-effect transistors (FETs). This study provides a promising method to fabricate vertically integrated 2D devices, which are essential in 2D material-based devices and circuits.

Nature Communications, Published online: 25 June 2022; doi:10.1038/s41467-022-31231-5

Graphene has long been considered to be a promising host for spin qubits, however a demonstration of long spin relaxation times for a potential qubit has been lacking. Here, the authors report the electrical measurement of the single-electron spin relaxation time exceeding 200 μs in a bilayer graphene quantum dot.

Here, using four metal halides and two chalcogenides as prototype material systems, their growth process is investigated and it is found that the growth temperature decreases by maximum 35% on van der Waals (vdW) templates compared with non-vdW substrates. This work provides a universal vdW template-assisted method for the low-temperature synthesis of high-crystallinity 2D materials toward applications in flexible electronics and carbon neutralization.

Abstract

To date, the synthesis of high-quality 2D crystals using vapor deposition methods usually requires high temperature, hindering the integration of 2D materials with Si circuits and exacerbating energy consumption. Exploring low-temperature growth strategies and understanding synthesis mechanism are critical for the practical application of 2D materials. Herein, a van der Waals (vdW) template-assisted growth of 2D crystals (including PbI₂, CdI₂, BiI₃, CuI, Sb₂Te_3, and Bi₂Se₃) is reported, the growth temperature decreases by maximum 35% compared with traditional vapor deposition. The low-temperature 2D growth process resulting from the low surface diffusion barrier of precursors on vdW surfaces is proposed, confirmed by the density functional theory and molecular dynamics calculations. Particularly, the grown 2D crystals can be peeled off from vdW templates easily and transferred to arbitrary substrates for functional applications and the exfoliated vdW templates can be reused for another round of growth. Although the growth temperature is reduced greatly, the excellent photoelectric performance of grown 2D crystals is demonstrated, benefitting from high crystalline quality. These findings provide a universal method for the low-temperature synthesis of high-crystallinity 2D materials toward applications in flexible electronics.

Tremendous efforts are devoted to explore 2D inorganic/organic based on different charge transfer (CT) types for photodetection. In this review, a comprehensive summary on 2D inorganic/organic CT heterojunction photodetectors with a whole new perspective is presented. Furthermore, the expanded functions and development on new materials, new structure, large scale compatibility, in-depth bio-application, and retino-morphic photonic are also outlined.

Abstract

2D materials possess superior optoelectronic properties, such as ultrahigh mobility and broadband photoresponse, making them one of the most vital platforms for diversified photodetectors. However, atomic thickness 2D materials usually suffer from intrinsic low absorption. To promote the photodetector performance, a feasible method is to integrate the 2D materials with low-cost, flexible, and tunable organics that form a charge transfer (CT) heterojunction. As results, in-depth multifunctional CT 2D-inorganic/organic detector exhibits extended functions such as low-power consumption, in-memory detection, and optical-bio synapse to meet the demand of contemporary photonic cell. Particularly, the progresses in wafer-scale monocrystal of both 2D and organic materials render vast potential applications with operation frequencies ranging from ultraviolet to terahertz. Here, the recent advances of 2D-inorganic/organic CT photodetectors are comprehensively reviewed by several classifications. Future developments and applications in optical biology, synapsis, and machine vision are also highlighted.

The synthesis of α-GeTe nanoplates on different substrates is reported via the chemical vapor deposition process and the systematical investigation of their structure and electrical properties. 2D α-GeTe nanoplates with excellent conductivity and an extraordinary breakdown current density provide an accessible strategy to improve the performance of 2D electronic devices.

Abstract

Two-dimensional (2D) materials have attracted extensive attention due to their important prospects in electronics and optoelectronics. Synthesizing new 2D materials, characterizing their properties, and developing their applications are still important topics. Herein, the synthesis of α-GeTe nanoplates on different substrates via the chemical vapor deposition process and the systematical investigation of their structure and electrical properties, is reported. By controlling the synthesis temperature and carrier gas, α-GeTe nanoplates, with a lateral dimension up to 30 µm and a thickness down to 1.2 nm, which corresponds to the thickness of one unit cell, can be obtained on 2D WSe₂ substrate. Electrical transport studies show 2D α-GeTe nanoplates have an excellent conductivity (9.33 × 10⁵ S m⁻¹) and an extraordinary breakdown current density (6.1× 10⁷ A cm⁻²). Compared with traditional WSe₂ transistors with deposited metal electrodes, the WSe₂ transistors with the metallic α-GeTe nanoplates as van der Waals metal electrodes achieved much better performance, such as higher on-state current (from 7.83 to 23.23 µA µm⁻¹) and electron mobility (from 16.5 to 75.0 cm² V¹ S¹). This study demonstrates an effective pathway to achieve ultrathin 2D materials and provides an accessible strategy to improve the performance of 2D electronic devices.

Single crystals of van der Waals layered antiferroelectric and magnetic CuCrP₂S₆ show a spontaneous macroscopic polarization mediated by the defect-dipole polarization at the quasi-antipolar state. The highly tunable local ferroelectric state and the defect-dipole polarization can be achieved by a temperature specific poling procedure and survive even without the external electric field. The defect-dipole is likely related to a metastable Cu site within the van der Waals gap and is a smoking gun of a uniaxial quadruple potential well.

Abstract

Recent success in experimental and theoretical works on metal thiophosphates (MTPs) paved the way to add multiple functionalities of complex oxides, such as ferroelectricity, in 2D materials. To realize multiferroicity and magnetoelectric coupling on layered van der Waals materials, incorporating magnetic ions in the ferroelectric framework is desirable. Unfortunately, replacing the metal ion with a magnetic one in MTPs results in antiferroelectricity in which spontaneous macroscopic polarization is absent. Herein, the emergence of a tunable local ferroelectric state in antiferroelectric CuCrP₂S₆ possessing magnetic Cr³⁺ ion is reported. The spontaneous macroscopic polarization is observed, which is switchable by an external poling field through controlling a defect-dipole polarization in the quasi-antipolar state. The observations suggest that the formation of defect dipoles, which is facilitated by an order-disorder-type structural transition, is likely related to a metastable Cu site within the van der Waals gap and therefore is a smoking gun of the existence of a uniaxial quadruple potential well. The interaction between the defect-dipole polarization and dipoles in the antipolar matrix may lead to the emerging local ferroelectricity in antiferroelectric CuCrP₂S₆. The findings suggest a possibility of utilizing the local ferroelectricity of multiferroic MTPs for novel 2D applications.

Publication date: July–August 2022

Source: Materials Today, Volume 57

Author(s): Bailing Li, Xia Deng, Weining Shu, Xing Cheng, Qi Qian, Zhong Wan, Bei Zhao, Xiaohua Shen, Ruixia Wu, Shun Shi, Hongmei Zhang, Zucheng Zhang, Xiangdong Yang, Junwei Zhang, Mianzeng Zhong, Qinglin Xia, Jia Li, Yuan Liu, Lei Liao, Yu Ye

Abstract

Two-dimensional anisotropic materials have been widely concerned by researchers because of their great application potential in the field of polarized detector devices and optical elements, which is a very important and popular research direction at present. As a IV–V two-dimensional material, silicon phosphide (SiP) has obvious in-plane anisotropy and exhibits excellent optical and electrical anisotropy properties. Herein, the optical anisotropy of SiP is studied by spectrometric ellipsometry measurements and polarization-resolved optical microscopy, and its electrical anisotropy is tested by SiP-based field-effect transistor. In addition, the normal and anisotropic photoelectric performance of SiP is shown by fabricating a photodetector and measuring it. In various measurements, SiP exhibits obvious anisotropy and good photoelectric performance. This work provides basic optical, electrical, and photoelectric performance information of SiP, and lays a foundation for further study of SiP and applications of SiP-based devices.