Decrease In Barrier Height Research Articles

Confinement Effects of Two-dimensional Surfaces on Water Adsorption and Dissociation over Pt(111).

It has been established that the confined space created by stacking a two dimensional (2D) surface atop a metal catalyst serves as a nano-reactor. According to recent research, when a graphene (Gr) overlayer encloses a Pt catalyst from above, the activation barrier for the water dissociation reaction, a process with major industrial significance, decreases. In order to investigate how the effect of confinement varies among different two-dimensional (2D) materials, we study the adsorption and dissociation barriers of water molecule on Pt(111) under graphene, hexagonal boron nitride (h-BN), and heptazine-based graphitic carbon nitride (g-C3N4) layers using density functional theory calculations. Our findings reveal that the strength of adsorption does not decrease consistently with a reduction in the height of the 2D overlayer. Furthermore, a smaller barrier is not always the consequence of poorer adsorption of the reactant. We also examine the effect of confinement on the shape of the reaction path, on the frequencies of vibrational modes, and on the rate constants derived using the harmonic transition state theory. Overall, all three of the 2D surfaces cause a decrease in barrier height and a weakening of adsorption, though to differing degrees due to a mix of mechanical, geometric and electronic variables.

Tuning Overbias Plasmon Energy and Intensity in Molecular Plasmonic Tunneling Junctions by Atomic Polarizability.

Plasmon excitation in molecular tunnel junctions is interesting because the plasmonic properties of the device can be, in principle, controlled by varying the chemical structure of the molecules. The plasmon energy of the excited plasmons usually follows the quantum cutoff law, but frequently overbias plasmon energy has been observed, which can be explained by quantum shot noise, multielectron processes, or hot carrier models. So far, clear correlations between molecular structure and the plasmon energy have not been reported. Here, we introduce halogenated molecules (HS(CH2)12X, with X = H, F, Cl, Br, or I) with polarizable terminal atoms as the tunnel barriers and demonstrate molecular control over both the excited plasmon intensity and energy for a given applied voltage. As the polarizability of the terminal atom increases, the tunnel barrier height decreases, resulting in an increase in the tunneling current and the plasmon intensity without changing the tunneling barrier width. We also show that the plasmon energy is controlled by the electrostatic potential drop at the molecule-electrode interface, which depends on the polarizability of the terminal atom and the metal electrode material (Ag, Au, or Pt). Our results give new insights in the relation between molecular structure, electronic structure of the molecular junction, and the plasmonic properties which are important for the development of molecular scale plasmonic-electronic devices.

Effects of contaminant diffusion on the fresh air inlets of a clean room workshop

In this study, a clean workshop is the subject of our research study, and computational fluid dynamics methods are applied to investigate the effect of exhaust pipe height, exhaust velocity, barrier structure, and wind direction on contaminant diffusion from the clean workshop. Results show that an increase in exhaust pipe height and exhaust velocity or a decrease in barrier height can effectively reduce the pollutant concentration at each fresh air inlet (FAI). Along the wind direction, the contaminant concentration initially increases and then decreases as distance increases. When the height of the exhaust pipe reaches 45 m, the effect of pollutants on the FAI is insignificant. When the exhaust velocity reaches 12 m/s, the effect of pollutants on the FAI weakens as the emission speed of flue gas increases. Reducing the height of the barrier to 29–31 m can effectively improve the concentration of pollutants at each FAI. Practical implications The mechanism by which the exhaust pipe height, exhaust velocity, barrier structure, and wind direction affect pollutant diffusion from a clean room workshop is systematically investigated by combining the CFD methods with an actual clean workshop as the research object, and the optimal pollutant reduction conditions are presented, thus providing scientific guidance for the construction of clean plants and the reduction of pollutant emissions.

Investigation of temperature dependant current transport mechanism in Ag/In2O3/p-Si/Al heterojunction

Employing the pulsed laser ablation technique nano-crystalline thin films of Indium oxide (In2O3) are deposited successfully on boron doped silicon substrate. The structural and morphological parameters of the films are investigated by using X-ray diffraction and atomic force microscopic (AFM) spectroscopy, respectively. The deposited films are the crystalline nanostructures with (400) as preferred diffraction peak and grain size of 56.56 nm approximately. The computed roughness (Rq) of In2O3 film is 1.02 nm. The AFM analysis validated the deposition of homogeneous smooth In2O3 films with surface roughness of the order of nanometer. UV–vis spectroscopy was used to study the optical properties of the films. Greater than 80% transparency in visible region was exhibited by the films. The value of the optical band gap was found to be 3.89 eV. The electrical parameters dominating the mechanism of current transport in n-In2O3/p-Si heterojunction were explored by observing the temperature-dependent current–voltage (I–V) properties. In the temperature range of 80–300 K, the ideality factor and barrier height were found to be strongly temperature dependent. It was noticed that with the decrease in temperature there is increase in ideality factor whereas decrease in barrier height which confirm the interfacial imperfections and inhomogeniety in potential barrier height distributions. The temperature dependence of I–V data has revealed the existence of double Gaussian distribution of barrier heights with mean values of 0.85eV and 0.78eV with standard deviation of 0.014 V and 0.012 V respectively. The modified Richardson's plot gives the average barrier height and Richardson's coefficient as 0.86eV and 4.7 × 105 Am−2K−2 in the temperature range 300 K–180 K and 0.77eV and 5.2 × 105 Am−2K−2, respectively in the temperature range 160 K–80 K. The values of Richardson's constants are of the order of known theoretical value of 3.2 × 105 Am−2 K−2.

Investigations of methane gas sensor based on biasing operation of n-ZnO nanorods/p-Si assembled diode and Pd functionalized Schottky junctions

In this work, we developed methane gas sensors based on zinc oxide nanorod (n-ZnO-NR) arrayed assembly, synthesized using aqueous phase deposition on p-Si(100) substrates, fabricated as pn junction besides chemical sensitization by Pd (Pdcat/n-ZnO-NR) and Pd-30wt%Ag (Pd–Agcat/n-ZnO-NR) forming Schottky junctions. These sensors are evaluated under reducing methane [CH4] gas with varying concentration (100–10,000 ppm or 0.01–1.0%) mixed with synthetic air under optimum temperature (≤200–230 °C) for thermal activation and UV A (365 nm) light activation supplemented with 50–100 °C, following increased electrical conductivity, bandgap narrowing, decreased barrier height, under biasing operation. The performance metrics include a high response (R; 45–80%), low limit of detection (LOD; 80–270 ppm), fast response-recovery times (<1–67 s), and strong binding constants (0.012–0.021), quantified from saturation current, transient response, and Langmuir adsorption isotherm, respectively. Every factor inducing a change in oxygen content of analyte gas atmosphere above ZnO include: (1) surface chemical reaction with chemisorbed oxygen ions on pristine and Pdcat or Pd-Agcat modified n-ZnO-NR yields electron donors increasing sensor conductance; (2) effective free carrier concentration and amplified interface-dipole allowing reduced barrier height and electron tunneling at high reverse bias prevailing depletion-driven mechanism; (3) faster electron transport shortening the response time due to weakened oxygen ion adsorption removed by analyte gas molecules; and finally, (4) in-depth study of thermal and UV activated processes is supported with space charge model and band-bending theory perspectives.

Modelling of Low-Voltage Varistors’ Responses under Slow-Front Overvoltages

In this study, commercially low-voltage MOVs are exposed to switching surges to analyse and model the relationship between the number of surges and the MOV grain barrier height response. Repeated slow-front overvoltage transients are used to degrade the protective qualities of metal oxide surge arrester devices, affecting their reliability and stability. A total of 360 MOVs with similar specifications from three different manufacturers are degraded under switching surges at a constant temperature of 60 °C. The reference voltage and C-V characteristics of MOVs are measured before and after the degradation process to analyse the MOVs’ conditions. Grain barrier heights are determined from the C-V characteristics curve. An F-statistical analysis is then applied to analyse the effects of number of surges on the grain barrier height. The T-test is used to assess the statistical difference between the tested groups. Linear regression analysis is then applied to model the relationship between the number of surges and MOV grain barrier height. The results obtained show that the number of surges has a significant impact on grain barrier height. MOV grain barrier height is found to decrease as the number of surges applied increases. Regression models obtained for the tested MOV groups across all three manufacturers agree and indicate that the reduction in grain barrier height results from an increased number of surges. Regression coefficients of a developed model indicate that for one surge applied, the MOV grain barrier height decreases by 0.024, 0.055, and 0.033 eV/cm for manufacturers X, Y, and Z, respectively. Therefore, there is a linear relationship between grain barrier height and the number of applied switching surges.

The Double Gaussian Distribution of Inhomogeneous Barrier Heights in Au/NAMA/n-Si Schottky Diodes

In this work, we report the results of temperature dependent barrier properties of Au/NAMA/n-Si Schottky diode in the low temperature range of 80–330 K. The analysis results of according to thermionic emission theory showed that the barrier height decreases, and the ideality factor increases towards low temperatures, depend on the barrier height inhomogeneities. The obtained results show the presence of a double Gaussian distributions with standard deviations (σ 0) of 0.073 V and 0.18 V and mean barrier height () values of 0.595 and 1.427 eV in the change of 80–140 K and 160–330 K, respectively. Moreover, evaluation of the modified Richardson curve, the values of Richardson constant (A*) of 321.805 and 110.935 A K−2 cm−2, and mean barrier height of 0.606 and 1.422 eV were found for the low- and high-temperature regions, respectively. The A* value of 110.935 A K−2 cm−2 is close to the theoretical value of 112 A K−2 cm−2 for n-Si. These results proved that there is barrier inhomogeneity.

All-epitaxial Al/AlGaN/GaN low-barrier Schottky diodes

All-epitaxial Al/AlxGa1−xN/GaN low-barrier Schottky diodes with different x compositions were fabricated in the single process of molecular-beam epitaxy. A decrease in the effective barrier height is achieved by polarization-induced δ-doping of the AlxGa1−xN/GaN heterojunction. At zero bias, the diodes have high values of ampere-watt sensitivity (7 A/W) with a low specific value of differential resistance (5 × 10−4 Ω⋅cm2) and retain non-linear properties when the resistance decreases to 10−4 Ω⋅cm2. The fundamental importance of the absence of impurities, oxides, and structural defects at the metal–semiconductor interface for effective control of the transport properties of diodes is demonstrated.

The temperature-dependent dielectric properties of the Au/ZnO-PVA/n-Si structure

In this work, the temperature-dependent (80–360 K) dielectric properties of the Au/ZnO-PVA/n-Si structure was investigated employing capacitance-voltage (C–V) and conductance-voltage (G/ω-V) experiments at 1 MHz. The results indicate that all electrical and dielectric variables in these structures are forcefully dependent on temperature. Also, using the interlayer ZnO-PVA nanocomposite has caused changes to these parameters. Because of the presence of series resistance, the amount of C and G/ω increases as the temperature rises. The values of EF increase with temperature, whereas the values of barrier height decrease from 1.045 eV to 0.943 eV, and the value of α extract from ΦB-T plot is obtained −3.5 × 10−4 eV/K that is approximately equal to the silicon temperature coefficient. The value of activation energy is obtained 0.04 eV which is a modest amount obtained from the conduction procedure's contribution to the boundary grains.

Dielectric relaxation properties, and AC conductivity of Erbium(III)-Tris(8-hydroxyquinolinato) nanostructured films

Thin films of Erbium (III)-Tris (8-hydroxyquinolinato (ErQ3) were accomplished by thermal evaporating procedure. The thermal stability of ErQ3 powder was studied by the differential scanning calorimeter (DSC). The SEM image of ErQ3 thin film revealed that the surface morphology of ErQ3 is composed from several of islands structure, meanwhile each island look like algae-shape. The variation of the dielectric real and imaginary parameters versus temperature and frequency were discussed. The real dielectric constant and dielectric loss show a remarkable dependence on the frequency and temperature. The activation energy of the relaxation process (ΔE) was found to be 0.428 eV. In addition, the density of localized states at Fermi levels N(Ef) was estimated to be 1.33×1018eV−1cm−3. AC conductivity at various frequencies and temperatures was investigated. At high frequency regime, the AC conductivity behavior was explained by Jonscher formalism. The charge transport mechanism was found to be controlled by the barrier hopping model (CBH). The decrease of the potential barrier height (Wm) as temperature increases unveils the growing of diffusion charges as the temperature increases. The decrease of the activation energy of the AC conductivity (ΔEAc) as the frequency increases confirms the effect of the applied frequency in the enhancement of the eletrons hopping between the two nieghoburing sites. Overall, the relatively small value of the potential barrier height (Wm) and the extensive localized electronic states encourages the utilizing of ErQ3 in designing the solar cell units.

Structural and Photocatalytic Studies on Oxygen Hyperstoichiometric Titanium-Substituted Strontium Ferrite Nanoparticles

Doping of ferrites is an important domain of research for their application as photocatalysts. In the present work, the effect of Ti4+ substitution on the structural and photocatalytic properties of strontium ferrite nanoparticles (NPs) is studied. Ternary doped Sr1−xTixFe2O4+δ ferrite NPs (x = 0.0–1.0) were synthesized by sol–gel methodology. Tetravalent Ti4+ ions caused oxygen hyperstoichiometry and enhancement in the surface area from 44.3 m2/g for SrFe2O4 NPs to 77.6 m2/g for Sr0.4Ti0.6Fe2O4+δ NPs. The average diameter of NPs ranged between 25–35 nm as revealed by TEM analysis. The presence of two sextets in the Mössbauer spectrum of pristine SrFe2O4 and Ti4+-substituted ferrite NPs and a paramagnetic doublet in the TiFe2O5 confirmed their phase purity. The photocatalytic potential of pure and Ti4+-substituted ferrite NPs was studied using nitroaromatic compounds, viz. pendimethalin, p-nitrophenol and Martius yellow, as model pollutants. Doped ferrite NPs with a composition of Sr0.4Ti0.6Fe2O4+δ NPs showed the highest degradation efficiency ranging from 87.2% to 94.4%. The increased photocatalytic potential was ascribed to the lowering of band gap (Eg) from 2.45 eV to 2.18 eV, a fourfold decrease in photoluminescence intensity, increased charge carrier concentration (4.90 × 1015 cm−3 to 6.96 × 1015 cm−3), and decreased barrier height from 1.20 to 1.02 eV. O2●− radicals appeared to be the main reactive oxygen species involved in photodegradation. The apparent rate constant values using the Langmuir–Hinshelwood kinetic model were 1.9 × 10−2 min−1, 2.3 × 10−2 min−1 and 1.3 × 10−2 min−1 for p-nitrophenol, pendimethalin and Martius yellow, respectively. Thus, tuning the Ti4+ content in strontium ferrite NPs proved to be an effective strategy in improving their photocatalytic potential for the degradation of nitroaromatic pollutants.

Over 12% efficient kesterite solar cell via back interface engineering

Kesterite Cu2ZnSn(S,Se)4 (CZTSSe) has attracted considerable attention as a non-toxic and earth-abundant solar cell material. During selenization of CZTSSe film at high temperature, the reaction between CZTSSe and Mo is one of the main reasons that result in unfavorable absorber and interface quality, which leads to large open circuit voltage deficit (VOC-def) and low fill factor (FF). Herein, a WO3 intermediate layer introduced at the back interface can effectually inhibit the unfavorable interface reaction between absorber and back electrode in the preliminary selenization progress; thus high-quality crystals are obtained. Through this back interface engineering, the traditional problems of phase segregation, voids in the absorber and over thick Mo(S,Se)2 at the back interface can be well solved, which greatly lessens the recombination in the bulk and at the interface. The increased minority carrier diffusion length, decreased barrier height at back interface contact and reduced deep acceptor defects give rise to systematic improvement in VOC and FF, finally a 12.66% conversion efficiency for CZTSSe solar cell has been achieved. This work provides a simple way to fabricate highly efficient solar cells and promotes a deeper understanding of the function of intermediate layer at back interface in kesterite-based solar cells.

Characteristic of flexible β-Ga2O3 Schottky barrier diode based on mechanical stripping process

The flexible transverse β-Ga2O3 Schottky barrier diode (SBD) was fabricated by transferring the stripped β-Ga2O3 single crystal film onto muscovite, and its electrical characteristic under flat and bending conditions were tested. It is found that the forward current of the device after bending increases in the small voltage range of 0–1 V and decreases in the large voltage range of 1–4.5 V as the curvature increases. This result is attributed to the two mechanisms that the barrier height decreases and the scattering increases with the increase of the curvature. The decrease in barrier height makes it easier for electrons to migrate from the cathode to the anode in small voltage range, while the current decreases in large voltage range due to scattering. It is further found that the maximum transconductance (gm) and subthreshold swing (SS) deteriorate with the increase of curvature and the corresponding voltage value of gm drifts to the right. In addition, the switch ratio of the device under flat conditions is 108, whereas in bending tests the switch ratio is 107 which is only reduced by one order of magnitude and it is essentially the same as the current level under flat conditions.

Effect of Downstream Plasma Exposure on Schottky Diodes Fabricated on β-Ga2O3

The effects of downstream plasma exposure on Ga2O3 Schottky diode forward and reverse IV characteristics were investigated. Ultra-wide bandgap semiconductor β-Ga2O3 has attracted increasing attention because of the prospects for use in next generation high-power electronics. However, the Ga2O3 surface has been reported to be particularly sensitive to plasma-induced damage, which could lead to device performance degradation[1]. In our study, the plasma treatments were performed using a PIE Scientific Tergeo Plasma Cleaner with O2, N2 or CF4 discharges. The system can be operated either in immersion mode or downstream mode. The samples were exposed to fluxes of electrons, ions and neutral and an rf power of 50 W was used to generate the plasma at a pressure of 400 mTorr, with a fixed treatment time of 1 min. Ti/Au and Ni/Au metallization were employed as the Ohmic and Schottky contacts, respectively, on the test diodes. Prior to the Schottky metal deposition, the samples were treated to ozone plasma/dilute HCl solution/ozone treatments to remove surface contamination. A Schottky barrier height of 1.1 eV was obtained for the reference sample without plasma treatment, and an ideality factor of 1.001 was achieved. From the forward I-V characteristic, as illustrated in Figure 1, the diodes exposed to CF4 showed a 0.25V shift from the I-V of the reference sample due to a Schottky barrier height lowering around 13.9%, as show in Table 1. The diodes exposed with N2 and O2 plasmas showed a decrease of Schottky barrier height of 2.5 and 6.5 % with O2 or N2 treatments, respectively, as shown in Figure 2. The effect of plasma exposure on the ideality factor of diodes treated with these plasmas was minimal; 0.2% for O2 and N2, 0.3% for CF4, respectively, as shown in Figure 2. The reverse leakage currents were 0.0012, 0.0022 and 0.0048 mA/cm2 for the diodes treated with O2, and CF4, and N2 respectively, as shown in Figure 3. The effect of downstream plasma treatment on diode on-resistance and on-off ratio were also very minimal as shown in Figure 4 and 5.[1] Jiancheng Yang, Zachary Sparks, Fan Ren, Stephen J. Pearton, and Marko Tadjer, J. Vac. Sci. & Technol. B36, 061201-1-9 (2018). Figure 1

Development of Ti3C2Tx/NiSe2 Nanohybrid‐Based Large‐Area Pressure Sensors as a Smart Bed for Unobtrusive Sleep Monitoring

AbstractSleep is a very important biological activity for humans as insufficient sleep can cause various issues such as depression, memory and attention problems, etc. Even though there are sleep tracking systems, the assessment methods are tiresome, expensive, and time‐consuming. In this context, smart textiles are provoking a growing interest owing to their capability to use them in sleep monitoring and various other applications. Further, in search of materials for E‐textiles, MXene‐based hybrids have emerged as an excellent choice for physical sensors. Herein, Ti3C2Tx/NiSe2 hybrid‐based pressure sensor on the cotton cloth is fabricated to be used as a smart bed for sleep monitoring. The fabricated Ti3C2Tx/NiSe2 hybrid‐based pressure sensor exhibits an enhanced value of sensitivity, i.e., ≈2.41 kPa−1 in comparison to the pristine Ti3C2Tx‐based sensor (≈1.58 kPa−1). The physical pressure sensing mechanism is explained using the concept of Schottky barrier height reduction and decrease in contact resistance between the as‐formed metal–semiconductor junction along with the shrinking of interlayer spacing of the layered NiSe2 and Ti3C2Tx. Finally, the fabricated sensor is used for real‐time sleep monitoring, which monitors the movement of an individual and also the breath rate, which possesses potential application in personal health‐care diagnosis.

Carbon nanotube fibers with high specific electrical conductivity: Synergistic effect of heteroatom doping and densification

Low contact resistance of carbon nanotube (CNT) fibers are fundamental component to improve the electrical transport properties of CNT fibers. To reduce the contact resistance of CNT fibers, we have demonstrated synergistic effect of macroscopic densification in combination with heteroatom doping. Boron and nitrogen atoms were introduced into the hexagonal carbon lattice of the CNTs through judicious combination of high temperature thermal doping and plasma treatment. Chlorosulfonic acid (CSA) was chosen to provide selectively quaternary nitrogen on the sidewall of the CNTs. During this process, densification of the CNT fibers also proceeded, and consequently reduced the hopping or tunneling distance for inter-CNT electron transfer. As a result, we achieved remarkable electrical conductivity of the CNT fibers as high as 5,896 Sm2/kg. The mechanism study by which heterogeneous conduction model proved the decrease of the electrical barrier height of the CNT fibers. These results provide a substantial step towards the use of CNT fibers as conductive materials.

Effect of Hydrostatic Pressure on the Revers Gate-Current of AlGaN/GaN HEMTs

In this paper, we present an Analytical-Numerical model for reverse gate leakage current in AlGaN/GaN high electron mobility transistors (HEMTs), which investigate the influence of the hydrostatic pressure (HP) on gate-current. Salient features of the model are incorporated of occupied sub-bands in the interface quantum well, combined with a self-consistent solution of the Schrödinger and Poisson equations. Finite difference techniques have been used to acquire energy eigenvalues and their corresponding eigenfunctions of AlGaN/GaN (HEMTs). It has been found that the bound charge at the heterointerface has the most impact on the threshold voltage. The increases in hydrostatic pressure cause an increase in threshold voltage. With increasing HP, the Schottky barrier height decreases, AlGaN electric field and reverse gate leakage current are increased. The increase in HP acts as a positive virtual gate. The dependence on the HP of Poole- Frenkel emission (FP) and Fowler-Nordheim (FN) direct tunneling is more than trap-assisted-tunneling (TAT). Increasing the pressure of 2GPa, the intersection point of PF and TAT varies by 1 volt, the reverse gate current increases by an average of 35%, and the threshold voltage increases to 1.15 V in absolute terms.

Characterization and evaluation of current transport properties of power SiC Schottky diode

This paper presents the characterization and evaluation of current transport properties of power SiC Schottky diode. The evaluation of the main Schottky diode properties is based on the proposed advanced model. This model allows assessing the effect of particular current transport mechanisms with high accuracy. The presence and influence of tunneling current in I-V characteristics are evident, mainly for low temperatures. Unlike previously published results, the proposed model provides areasonable slight decrease of Schottky barrier height with increasing temperature due to the narrowing of the energy bandgap. The results and model are validated by finite element method (FEM) electrophysical simulations. Evaluated parameters of SiC Schottky diode, such as Schottky barrier height of 1.28 eV and Richardson constant of 1.46 × 106 Am−2K−2 are in good agreement with recent research and FEM simulations.

Development of a rGO-BiVO4 Heterojunction Humidity Sensor with Boosted Performance.

Humidity sensors with good repeatability, low hysteresis, and low-power consumption are increasingly important for environmental monitoring and industrial control applications. Herein, an impedance-type humidity sensor under low working voltage (5 mV) utilizing a rGO-BiVO4 nanocomposite is demonstrated. The rGO-BiVO4 humidity sensor exhibits superior sensing performances, including good repeatability, negligible hysteresis (0.47%), fast response and recovery time, low power consumption, good stability, and anti-interference ability. The ultraviolet-visible absorption spectrum reveals that the narrow band gap of the rGO-BiVO4 nanocomposite is conductive to the electron transfer. The complex impedance spectra and the energy band structure analysis further suggest that the boosted humidity performance results from the formation of a heterojunction and the decrease of the heterojunction barrier height. The facile fabrication route, enhanced sensing performance, and excellent device reliability make the rGO-BiVO4 sensor highly attractive for high-end humidity sensing applications.

Effects of Downstream Plasma Exposure on β-Ga2O3 Rectifiers

The effects of downstream plasma exposure with O2, N2 or CF4 discharges on Si-doped Ga2O3 Schottky diode forward and reverse current-voltage characteristics were investigated. The samples were exposed to discharges with rf power of 50 W plasma at a pressure of 400 mTorr and a fixed treatment time of 1 min to simulate dielectric layer removal, photoresist ashing or surface cleaning steps. Schottky contacts were deposited through a shadow mask after exposure to avoid any changes to the surface. A Schottky barrier height of 1.1 eV was obtained for the reference sample without plasma treatment, with an ideality factor of 1.0. The diodes exposed to CF4 showed a 0.25 V shift from the I–V of the reference sample due to a Schottky barrier height lowering around 14%. The diodes showed a decrease of Schottky barrier height of 2.5 and 6.5% with O2 or N2 treatments, respectively. The effect of plasma exposure on the ideality factor of diodes treated with these plasmas was minimal; 0.2% for O2 and N2, 0.3% for CF4, respectively. The reverse leakage currents were 1.2, 2.2 and 4.8 μA cm−2 for the diodes treated with O2, and CF4, and N2 respectively. The effect of downstream plasma treatment on diode on-resistance and on-off ratio were also minimal. The changes observed are much less than caused by exposure to hydrogen-containing plasmas and indicate that downstream plasma stripping of films from Ga2O3 during device processing is a relatively benign approach.