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Gastric cancer (GC) is one of the most common and lethal types of cancer affecting over one million people, leading to 768,793 deaths globally in 2020 alone. The key for improving the survival rate lies in reliable screening and early diagnosis. Existing techniques including barium-meal gastric photofluorography and upper endoscopy can be costly and time-consuming and are thus impractical for population screening. We look instead for small extracellular vesicles (sEVs, currently also referred as exosomes) sized ⌀ 30-150 nm as a candidate. sEVs have attracted a significantly higher level of attention during the past decade or two because of their potentials in disease diagnoses and therapeutics. Here, we report that the composition information of the collective Raman-active bonds inside sEVs of human donors obtained by surface-enhanced Raman spectroscopy (SERS) holds the potential for non-invasive GC detection. SERS was triggered by the substrate of gold nanopyramid arrays we developed previously. A machine learning-based spectral feature analysis algorithm was developed for objectively distinguishing the cancer-derived sEVs from those of the non-cancer sub-population. sEVs from the tissue, blood, and saliva of GC patients and non-GC participants were collected (

We demonstrated 1 the formation of excellent Ohmic contact to p-type GaN (including the plasma etching-damaged p-type GaN which otherwise exhibited undetectable current within 15V) by the post-growth diffusion of magnesium. The specific contact resistivity on the order of 10-4 Ω.cm2 (extracted at V=0V) was achieved on the plasma-damaged p-GaN with linear current-voltage characteristics by the transfer length method (TLM) measurement. The improvement in current by a factor of over 109 was also obtained on the plasma-damaged p-n junction diode after the same Mg-treatment. These experimental results indicate a great potential of post-growth diffusion of Mg to overcome the bottleneck of forming a good Ohmic contact to p-GaN.

An emerging body of research by biologists and clinicians has demonstrated the clinical application of small extracellular vesicles (sEVs, also commonly referred to as exosomes) as biomarkers for cancer detections. sEVs isolated from various body fluids such as blood, saliva, urine, and cerebrospinal fluid have been used for biomarker discoveries with highly encouraging outcomes. Among the biomarkers discovered are those responsible for multiple cancer types and immune responses. These biomarkers are recapitulated from the tumor microenvironments. Yet, despite numerous discussions of sEVs in scientific literature, sEV-based biomarkers have so far played only a minor role for cancer diagnostics in the clinical setting, notably less so than other techniques such as imaging and biopsy. In this paper, we report the results of a pilot study (n = 10 from each of the patient and the control group) using bronchoalveolar lavage fluid to determine the presence of sEVs related to non-small cell lung cancer in twenty clinical samples examined using surface enhanced Raman spectroscopy (SERS).

On-chip electrostatic discharge (ESD) protection is becoming more challenging for integrated circuits (ICs) made in advanced technology nodes. The ESD-induced design overhead, including ESD parasitic effects and layout area, inherent to the traditional in-Silicon PN-junction-based ESD protection devices, rapidly becomes unbearable to high-performance and complex ICs. A disruptive above-Si mechanical ESD switch device, made in CMOS backend using a graphene nano-electromechanical-system (gNEMS) structure, was recently devised and demonstrated using poly-crystalline graphene films. This paper reports design, fabrication and comprehensive characterization of single-crystalline gNEMS ESD switch devices. Measurement using transmission line pulse (TLP) and very fast transmission line pulse (VFTLP) ESD testing reveals superior ESD protection capability of gNEMS devices made in single-crystalline graphene over its poly-crystalline counterparts, achieving a record-high ESD current handling capability of ${\text{I}}_{t2} {\sim }1.19 {\times }10^{10}\text{A}$ /cm2 under TLP zapping and ${\text{I}}_{t2} {\sim }6.09{\times }10^{9}\text{A}$ /cm2 under VFTLP stressing. The ESD robustness enhancement related to single-crystalline graphene material property is discussed.

Photodetectors are one of the most important components for a future "Internet-of-Things" information society. Compared to the mainstream semiconductor-based photodetectors, emerging devices based on two-dimensional (2D) materials and ferroelectrics as well as their hybrid systems have been extensively studied in recent decades due to their outstanding performances and related interesting physical, electrical, and optoelectronic phenomena. In this paper, we review the photodetection based on 2D materials and ferroelectric hybrid systems. The fundamentals of 2D and ferroelectric materials as well as the interaction in the hybrid system will be introduced. Ferroelectricity modulated optoelectronic properties in the hybrid system will be discussed in detail. After the basics and figures of merit of photodetectors are summarized, the 2D-ferroelectrics devices with different structures including p-n diodes, Schottky diodes, and field-effect transistors will be reviewed and compared. The polarization of ferroelectrics offers the possibility of the modulation and enhancement of the photodetection in the hybrid detectors, which will be discussed in depth. Finally, the challenges and perspectives of the photodetectors based on 2D ferroelectrics will be proposed. This Review outlines the important aspects of the recent development of the hybrid system of 2D and ferroelectric materials, which could interact with each other and thus lead to photodetectors with higher performances. Such a Review will be helpful for the research of emerging physical phenomena and for the design of multifunctional nanoscale electronic and optoelectronic devices.

Design processes of a large-scale negative ion accelerator for neutral beam injection (NBI) application involve a series of physics and engineering issues, which include high voltage holding, background gas and stripping losses, beamlets optics and steering, particle and power flux on the grid electrodes, heat removal, thermal deformation, and stress of the grids. A self-consistent design model covering all these critical issues has been developed, where the results of one design aspect can be directly plugged into another one as the input conditions with little approximation or assumption. This design model has been applied to the negative ion accelerator of the NBI test facility of CRAFT (Comprehensive Research Facility for Fusion Technology), which is designed to produce a negative hydrogen ion beam of 25 A with the particle energy of 400 keV and the pulse duration of 3600 s. The accelerated current density is required to be 210 A/m2 from 768 apertures with a diameter of 14 mm. The evaluated results of the CRAFT accelerator design are quantitatively analyzed. Additionally, the modeling is applied to a large-scale and relatively complete structure of the multi-grid electrodes. Hence, some nonuniformities or special distributions appear in different design issues, which were not noticed in the reference works.

The potential in a synaptic simulation for neuromorphic computation has revived the research interest of resistive random access memory (RRAM). However, novel applications require reliable multilevel resistive switching (RS), which still represents a challenge. We demonstrate in this work the achievement of reliable HfO2-based RRAM devices for synaptic simulation by performing the Al doping and the postdeposition annealing (PDA). Transmission electron microscopy and operando hard X-ray photoelectron spectroscopy results reveal the positive impact of Al doping on the formation of oxygen vacancies. Detailed I–V characterizations demonstrate that the 16.5% Al doping concentration leads to better RS properties of the device. In comparison with the other reported results based on HfO2 RRAM, our devices with 16.5% Al-doping and PDA at 450 °C show better reliable multilevel RS (∼20 levels) performance and an increased on/off ratio. The 16.5% Al:HfO2 sample with PDA at 450 °C shows good potentiation/depression ch...

Future “Internet of Things” requires transferable ferroelectric thin films for functional devices like sensors and actuators. We report here the growth of a typical ferroelectric perovskite compound, BaTiO3, on a graphene monolayer which remains intact during the oxide growth process at high temperatures and at elevated oxygen pressure. The graphene facilitates the crystallization of BaTiO3. The growth of BaTiO3 on the graphene monolayer is found to follow the Volmer–Weber mode with the formation of three dimensional islands at the initial growth stage. Highly (001)-oriented BaTiO3 crystalline films are fabricated and can be easily exfoliated using a metal stressor layer. The graphene monolayer remains attached to the exfoliated BaTiO3 film which demonstrates good piezoelectric properties. These results not only demonstrate the possibility to fabricate high quality crystalline ferroelectric films via a graphene monolayer, but also open the pathway to realize van der Waals epitaxy ferroelectric films which can be transferred onto arbitrary substrates, particularly onto flexible substrates for wearable devices applications.

Hot electron transistors (HETs) containing two-dimensional (2D) materials promise great potential in high-frequency analog and digital applications. Here, we experimentally demonstrate all-2D van der Waals (vdW) HETs formed by graphene, hBN, and WSe2, in which the polarity of carriers could be tuned by changing bias conditions. We proposed a theoretical model to distinguish hot hole and hot electron components in the ambipolar vdW HET. Importantly, both hot hole and hot electron modes are achieved with pronounced saturation behavior as well as record-high collection efficiency approaching theoretical limits (99.9%) at room temperature. The vdW HETs show a maximum output current density of 400 A/cm2. The observed ambipolar hot carrier transport with high collection efficiency is promising for high-speed nanoelectronics and 2D hot electron spectroscopy.

Interfacial quantum states are drawing tremendous attention recently because of their importance in design of low-dimensional quantum heterostructures with desired charge, spin, or topological properties. Although most studies of the interfacial exchange interactions were mainly performed across the interface vertically, the lateral transport nowadays is still a major experimental method to probe these interactions indirectly. In this Letter, we fabricated a graphene and hydrogen passivated silicon interface to study the interfacial exchange processes. For the first time we found and confirmed a novel interfacial quantum state, which is specific to the 2D-3D interface. The vertically propagating electrons from silicon to graphene result in electron oscillation states at the 2D-3D interface. A harmonic oscillator model is used to explain this interfacial state. In addition, the interaction between this interfacial state (discrete energy spectrum) and the lateral band structure of graphene (continuous energy spectrum) results in Fano-Feshbach resonance. Our results show that the conventional description of the interfacial interaction in low-dimensional systems is valid only in considering the lateral band structure and its density-of-states and is incomplete for the ease of vertical transport. Our experimental observation and theoretical explanation provide more insightful understanding of various interfacial effects in low-dimensional materials, such as proximity effect, quantum tunneling, etc. More important, the Fano-Feshbach resonance may be used to realize all solid-state and scalable quantum interferometers.

Colloidal quantum dots (QDs) have attracted a great amount of attention for their appealing optoelectronic properties. In this work, the CuInS2 (CIS)/ZnS core/shell QDs based on 4.3 nm cores with various layers of ZnS shell (0 to 10) were synthesized. With the sequential growth of a ZnS shell over a CIS core, the band alignment of core/shell QDs converts from a type I to quasi-type II structure. This conversion prolongs the carrier lifetime and affects the electron transfer rate (Ket) and electron transfer efficiency (ηET). A comparative study indicates that the photovoltaic performance of CIS based QDSCs can be markedly improved by optimizing the layers of ZnS shell. The highest photo conversion efficiency (PCE) of 2.07% is obtained at optimum ZnS thickness of about 1.55 nm. These results show tuning the thickness of shell to change the band alignment is an effective strategy to manipulate the carriers transportation behaviors and thus affect the PCE of CIS-based optoelectronic devices.

Future synaptic simulation using resistance random access memory (RRAM) requires higher reliability and lower power consumption of the devices and understanding of the correlation of the materials with their multi-level resistance switching (RS) properties. Using O3 pretreatment on a TiN electrode, this work highlights the significant role of the interface in the enhancement of the reliability and the power consumption of HfO2-based RRAM devices. X-ray photoelectron spectroscopy investigations indicate increases of the TiON and TiO2 components with the augmentation of the number of O3 treatment cycles, which strongly impacts the RS properties of the Pt/HfO2/TiN devices. Optimal RS properties were obtained for 20 O3 pulse-pretreated devices, which were used to emulate biological synapses after an annealing process. Analog memory properties, including analog set and reset in DC mode and potentiation/depression based on two types of designed pulses, have been achieved. Finally, one of the biological synapse learning rules, spike-timing-dependent plasticity, was successfully emulated. These results, avoiding the conventional route based on dual-layer insulators, are of significance for synaptic simulation using interface-engineered single-layer HfO2 RRAM and further reveal the internal mechanism of HfO2-based electron synapses.

We reported the first-time utilization of ELO (epitaxial lateral overgrowth) GaN (gallium nitride) for power diodes. The undesired stage of coalescence related to ELO is avoided by virtue of a novel 3D device architecture built on the ELO GaN islands on foreign substrate which features pure-lateral p-n and n+ -n-junctions and electrodes lying on the opposing sidewalls of the island. Excellent electrical performance was demonstrated, revealing a strong potential of ELO GaN with 3D device architecture for power switching applications.

Surface enhanced Raman spectroscopy (SERS) holds great promise in biosensing because of its single-molecule, label-free sensitivity. We describe here the use of a graphene-gold hybrid plasmonic platform that enables quantitative SERS measurement. Quantification is enabled by normalizing analyte peak intensities to that of the graphene G peak. We show that two complementary quantification modes are intrinsic features of the platform, and that through their combined use, the platform enables accurate determination of analyte concentration over a concentration range spanning seven orders of magnitude. We demonstrate, using a biologically relevant test analyte, the amyloid β-protein (Aβ), a seminal pathologic agent of Alzheimer’s disease (AD), that linear relationships exist between (a) peak intensity and concentration at a single plasmonic hot spot smaller than 100 nm, and (b) frequency of hot spots with observable protein signals, i.e. the co-location of an Aβ protein and a hot spot. We demonstrate the detection of Aβ at a concentration as low as 10(−18) M after a single 20 μl aliquot of the analyte onto the hybrid platform. This detection sensitivity can be improved further through multiple applications of analyte to the platform and by rastering the laser beam with smaller step sizes.

Large-scale close-packed two-dimensional (2D) colloidal crystal with high coverage is indispensable for various promising applications. The Langmuir-Blodgett (LB) method is a powerful technique to prepare 2D colloidal crystals. However, the self-assembly and movement of microspheres during the whole LB process are less analyzed. In this study, we clarify the crucial impact of hydrophilicity of the microspheres on their self-assembly in the LB process and on the properties of the prepared 2D colloidal crystals. The characteristic surface pressure-area isotherms of the microspheres have been analyzed and adjusted by only counting the quantity of the microspheres on the water surface, which leads to more accurate results. The critical surface pressures for hydrophilic and hydrophobic microspheres are about 61 and 46 mN/m, respectively. The decrease of the surface hydrophilicity of microspheres facilitates their self-assembly on the water surface, which further leads to higher coverage and less defects of the 2D colloidal crystals. A coverage of as high as 97% was obtained using hydrophobic microspheres. Entropy and intersphere capillary forces drive the self-assembly and transportation of the microspheres, respectively. Caused by the diffraction of visible light, opposite contrasts at local adjacent regions on the surface of the 2D colloidal crystals have been observed. The understanding of self-assembly of the microspheres during the LB process paves the way to fabricate the high-quality 2D colloidal crystals for various applications such as photonic papers and inks, stealth materials, biomimetic coatings, and related nanostructures.

The potential in a synaptic simulation for neuromorphic computation has revived the research interest of resistive random access memory (RRAM). However, novel applications require reliable multilevel resistive switching (RS), which still represents a challenge. We demonstrate in this work the achievement of reliable HfO

Previous studies have mainly focused on the resistive switching (RS) of amorphous or polycrystalline HfO

Surface-Enhanced Raman Scattering (SERS) is used to differentiate two colon cancer cell line HCT 116, that is, to distinguish a TP53 gene knockout cell line (p53 -/-) from a wild type (p53 +/+). A label-free graphene/gold nanopyramid based SERS platform, combined with the multivariate analysis: principal component analysis, is used to profile live, dead, and burst colon cancer cells suspended in simulated body fluid (SBF). The graphene sheet permits SERS hotspot identification and provides a chemical enhancement for the biological constituents. This study found that a unique fingerprint exists for three different states of the cell, burst, live, and dead, which were used to differentiate the p53 +/+ and p53 -/- cell lines. Perceptron with Pocket Algorithm was also coupled with PCA to demonstrate an average of 81% sensitivity and 97% specificity in separating the two cell lines. The demonstration of single gene differentiation shows the great applicable potential of this SERS graphene hybrid platform for cancer diagnosis.

By hot-injection method with altering the dose of oleylamine (OAm) in a reaction system, CuInS2 (CIS) nanocrystal with tunable structure and band gap is synthesized. Through various measurements, including X-ray diffraction (XRD), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS), it is demonstrated experimentally that when the dose of OAm is relatively high (2.0 and 2.5 ml in this work), the combination phase of pseudo-chalcopyrite/wurtzite are obtained with a surprising existence of nanotwins. Besides, the molar fraction of wurtzite is larger in the sample using 2.5 ml OAm in the reaction system. However, when the dose of OAm becomes low, (0, 1.0 and 1.5 ml), pure zinc-blende CIS pyramidal quantum dots (QDs) can be prepared. This indicates that oleylamine promotes the formation of wurtzite structure. In addition, the band gap is larger with increasing of OAm, following the quantum refinement effects. This work serves as a facile method of synthesizing CIS nanocrystal with tunable structure and band gap, which will be possibly applied in the fabrication of their optoelectronic devices. Keywords: CuInS2 nanocrystal, Tunable, Structure, Band gap, Optical properties

A novel serpentine-channeled mask was introduced to Si substrate for low-dislocation GaN epitaxial growth and the fully coalesced GaN film on the masked Si substrate was achieved for the first time. Compared with the epitaxial lateral overgrowth (ELOG) growth method, this innovative mask only requires one-step epitaxial growth of GaN which has only one high-dislocation region per mask opening. This new growth method can effectively reduce dislocation density, thus improving the quality of GaN significantly. High-quality GaN with low dislocation density ∼2.4 × 107 cm−2 was obtained, which accounted for about eighty percent of the GaN film in area. This innovative technique is promising for the growth of high-quality GaN templates and the subsequent fabrication of high-performance GaN-based devices like transistors, laser diodes (LDs), and light-emitting diodes (LEDs) on Si substrate.

Construction of heterojunctions has aroused great interest recently in the photocatalysis field because of the special electronic band structure and unique physicochemical properties. In this work, a novel 0D/3D CuO/ZnO heterojunction was obtained via in situ deposition of CuO nanoparticles on the flowerlike ZnO surface using the wet chemistry method. After depositing CuO nanoparticles onto the ZnO, the CuO/ZnO heterojunction exhibits enhanced visible-light harvesting and effective separation of the photogenerated electron–hole pairs compared with those in the pure ZnO. The photocatalytic removal efficiency of phenol over the CuO/ZnO heterojunction is up to 78% under the irradiation of the light, which is ∼2 and ∼4 times higher than those of the pristine ZnO and CuO, respectively. This composite also presents good durability and stability for phenol degradation in the photocatalytic reactions. Additionally, in the photodegradation system of the CuO/ZnO heterojunction, the superoxide radicals (•O2–) and hy...

A novel quasi core-shell structure of hierarchical ZnO coated with graphene, has been synthesized by a simple solvothermal method. After loading graphene on the surface of hierarchical ZnO, an intimate interfacial contact between them has been achieved. The experimental results indicate that hierarchical ZnO&Graphene composites (HZ&G) have large specific surface area, enhanced light harvesting in the visible light region, better separation efficiency and fast transfer rate of photo-generated carriers. Therefore, the HZ&G composites exhibit superior photocatalytic degradation efficiency over Rhodamine B (RhB) compared to pure hierarchical ZnO. Especially for HZ&G 15 composite with the nominal weight concentration of 15% GO, its removal rate of simulated pollutants is up to 98.5% under current experimental conditions. The primary reactive species in the process of photocatalytic RhB degradation is also confirmed by trapping experiments to be hydroxyl radicals (•OH). Meanwhile, a probable mechanism of enhancement over photocatalytic RhB degradation has been proposed.

Jellylike cylinder graphene-Mn3O4 composite with highly coupled effect was successfully synthesized by a simple solvothermal process. Without using toxic reducing agent and expensive equipment, this method is environmental compatible and suitable for low cost mass production. High capacitance Mn3O4 nanoparticles are homogeneously anchored on excellent conductivity graphene framework and a growth mechanism is hypothesized. Excellent electron conductivity and unique structure of Mn3O4-graphene composite give rise to various applications such as microwave absorber and electrode material. As a microwave absorber, the composite exhibits lowest reflection loss of −14.2 dB in the frequency range of 2–18 GHz. Good microwave absorption performance is due to the structure of the composite where conductive channels form between nano sized Mn3O4 and high conductivity graphene with defects and dangling bonds. As for electrochemical property, Mn3O4-graphene composite with coupled effect shows excellent performance with highest specific capacitance of 246.7 F g−1 in saturated K2SO4 at a scan rate of 5 mV s−1. Good electrochemical property is also attributed to the structure with high utilization of Mn3O4, fast charge carrier transmission, and excellent electronic conductivity. This composite shows a promising application in absorbing materials and electrodes.

Integrated circuits (ICs) require robust and low-parasitic on-chip electrostatic discharging (ESD) protection. Compared to conventional in-Si PN-junction-based ESD protection structures, a novel above-IC graphene nanoelectromechanical system (NEMS) switch (gNEMS) ESD protection structure features low parasitic effects and superior current and heat handling capability. This work reports a systematic transient characterisation of gNEMS ESD switches by transmission line pulse (TLP) measurement for human body model ESD protection, revealing transient ESD discharging behaviours related to device dimensions and TLP pulse shapes. It provides practical design guidelines for using gNEMS switch as on-chip ESD protection for ICs. Unlike in-Si ESD protection structures, the new gNEMS ESD switch devices can be made in the back-end-of-line of ICs through three-dimensional heterogeneous integration.

Graphene is a two-dimensional carbon material with extraordinary mechanical properties. However, recent studies have found that the presence of grain boundaries significantly decreases fracture stress of graphene, warranting further investigation. This work reports the development of a new method to measure the fracture stress of monolayer graphene with a novel nanoelectromechanical system (NEMS) structure. Suspended graphene ribbon devices with a range of geometries were electrostatically actuated while the graphene sheet was pinned down with various nail structures. By recording the electromechanical responses at fracture and using finite element simulations, the fracture stress was calculated. Using this novel NEMS structure, the fracture stress of polycrystalline graphene grown using conventional chemical vapour deposition (CVD) and single-crystalline graphene grown using local feeding CVD were found to be ∼30 and ∼90 GPa, respectively.

International audience; Field effect transistors (FETs) using two-dimensional molybdenum disulfide (MoS 2) as the channel material has been considered one of the most potential candidates for future complementary metal-oxide-semiconductor technology with low power consumption. However, the understanding of the correlation between the device performance and material properties, particularly for devices with scaling-down channel lengths, is still insufficient. We report in this paper back-gate FETs with chemical-vapor-deposition grown and transferred MoS 2 and Zr doped HfO 2 ((Hf,Zr)O 2 , HZO) high-k dielectric gates with channel lengths ranging from 10 to 30 μm with a step of 5 μm. It has been demonstrated that channels with the length to width ratio of 0.2 lead to the most superior performance of the FETs. The MoS 2 /HZO hybrid FETs show a stable threshold voltage of ∼1.5 V, current on/off ratio of >10 4 , and field effect mobility in excess of 0.38 cm 2 V −1 s −1. The impact of the channel lengths on FET performance is analyzed and discussed in depth. A hysteresis loop has been observed in the I ds − Vgs characteristics of the hybrid FETs, which has been further studied and attributed to the charge effect at the interfaces. The HZO films show a relatively weak ferroelectric orthorhombic phase and thus serve mainly as the high-k dielectric gate. Charge trapping in the HZO layer that might induce hysteresis has been discussed. Our results show that MoS 2 /HZO hybrid FETs possess great potential in future low power and high-speed integrated circuits, and future work will focus on further improvement of the transistor performances using ferroelectric HZO films and the study of devices with even shorter MoS 2 channels.

We have demonstrated non-polar GaN power diodes (Schottky barrier diode and p–n junction diode) on foreign substrates featuring the true-lateral p–n and metal–semiconductor junctions. The diodes were fabricated on GaN islands laterally overgrown on the mask-patterned sapphire and Si substrates by metalorganic vapor phase epitaxy. The anode and cathode were formed on the opposed a-plane sidewalls of the island, making the device architecture essentially like the 90° rotation of the desired true-vertical power diodes. The ideality factor of the Schottky barrier diode remained 1.0 (from 1.00 to 1.05) over 7 decades in current. Specifically, a high critical electric field of 3.3 MV/cm was demonstrated on the p–n junction diode with avalanche capability. These performances reveal a strong potential of non-polar GaN with the true-lateral junctions for high power applications.

Graphene is a 2D material with extraordinary electronic and mechanical properties and has a wide range of applications. Among existing synthesis methods, chemical vapor deposition (CVD) onto Cu foil is the most prominent because it allows large area high quality graphene to be prepared at relatively low costs and then subsequently wet transferred to arbitrary substrates. Typically, PMMA and FeCl 3 are used as a polymeric support layer and a metal etchant respectively during wet transfer. Unfortunately, this method leaves graphene susceptible to contamination, degrading transferred graphene's extraordinary properties. In this paper, contamination in the form of black particulates is identified to be Fe wrapped in graphene and a model of how it originates was developed. Then, a procedure to reduce this contamination during wet transfer was developed and its effectiveness was systematically studied. Transfers were characterized using Raman spectroscopy and optical microscopy with image segmentation. Experimental data obtained indicates that this simple and economic method is very effective in reducing Fe contamination on transferred CVD graphene, offering a way to improve the wet transfer process.