Atomic Displacements Research Articles

Thermal characteristics of CsPbX3 (X =Cl/Br/I) halide perovskites

Halide perovskites represent a remarkably promising category of materials for the development of novel solar cells and opto-electronic devices. In this study, we used the neuroevolution machine learning potential to examine the thermal properties of CsPbX3 perovskites (X = Cl / Br / I). In alignment with previous research, our results disclose a pronounced correlation between lattice dynamics and thermal conductivity. Regardless of the specific perovskite variant, phonon band structure analysis revealed dynamical instability, characterized by overlapping phonon branches and densely packed optical branches beginning at imaginary low frequencies around 20i cm−1. We observed a significantly low lattice thermal conductivity of approximately 0.20W/(mK). This is due to the displacement of Cs atoms from their central positions and the deformation of the PbX6 octahedra, which results in lower phonon velocities and shorter phonon lifetimes.

Investigation of the sintering behavior of nanoparticulate SiC by molecular dynamics simulation

Sintering is a valuable processing technique utilized to create bulk materials from powder compacts. In recent years, sintering has a garnered significant attention in the research community due to its versatility and applicability in various fields, including additive manufacturing. Herein, we investigate the sintering kinetics and mechanism of SiC nanoparticulate using molecular dynamics simulations. The surface morphology, microstructure, radial distribution function, mean square displacement, atomic displacement distribution, structural transformation, and diffusion coefficient are analyzed in detail. The free surface surrounding the neck undergoes a reconstruction to eventually reach an equilibrium dihedral angle. The neck rapidly grows and aligns with the surface, causing the SiC particle to transform from an original spherical shape into a twists shape. The concentration of shear stress results in a change of the local lattice structure from the face-centered cubic phase to amorphous phase in the surface. With an increasing sintering time, the dominant diffusion mechanism gradually shifts from surface diffusion to interface diffusion. This trend leads to a rise in the atomic migration, the consumption of interface energy, and the degree of particle fusion. Ultimately, the sintered SiC particles have the spherical shape, low surface energy, and stable structure. Additionally, the high mobility of melted atom causes a gradual dissolution of SiC particle into the large particle from the surface towards the interior. This process leads to high-altitude concentration structures that facilitate atomic migration. These results shed light on an atomic sintering mechanism in SiC nanoparticulate for applications in the preparation of nanostructured materials, and additive manufacturing.

Systematic study of displacement threshold and the near-threshold primary radiation damage model

Radiation damage is a critical concern for materials employed in radiation environments such as space, radiotherapy centers, and nuclear energy systems. Numerous models have been developed to estimate the primary radiation damage. The slightly modified Athermal Recombination-Corrected (mARC)-Displacement per Atom (DPA) model proposes a simple function to describe the atomic displacement near the Threshold Displacement Energy (TDE). The present work systematically investigates the global minimum TDE and the near-TDE mARC-DPA model against experimental electron irradiation damage data for 26 materials. The determined high-accuracy global minimum TDE values are generally consistent with previous studies. The corresponding theoretical calculations agree well with experimental measurements, implying the applicability of the mARC model. Renormalization of certain experimental data is required due to the potential issues related to experimental measurements, the value of resistivity change per Frenkel pair (ρFP), or average TDE (Ed). Nevertheless, while some experimental data are supposed to be adjusted, the analysis shows that the ratio of ρFP/Ed can be definitively determined if assuming the experimental data for the remainders.

Kr Adsorption in Porous Carbons: Temperature-Dependent Experimental and Computational Studies†.

The temperature dependence of the adsorption energy of krypton adsorption on activated carbon materials was studied by experiment and simulation. Adsorption isotherms were measured at temperatures from 250 to 330 K and analyzed with Henry's law. The adsorption energy determined from these measurements was found to weaken by more than 10% in this range. Slit pore widths for simulations in this work were modeled by the removal of integral numbers of planes in graphite. Vibrational dynamics of the krypton adsorbate and the carbon atom adsorbent were calculated with the stochastic temperature-dependent effective potential (sTDEP) method, using energetics from density functional theory (DFT) with the many-body dispersion energy method (MBD). Thermal displacements of carbon atoms had a negligible effect on the adsorption energy. The width of the slit pore had the greatest effect on the surface dynamics and the energies of the adsorbate atoms at different temperatures. Assuming a distribution of pore widths, the Boltzmann distribution of site occupancies causes a large weakening of the thermally averaged adsorption energy at higher temperatures.

Toxic, radioactive, and disordered: a total scattering study of TlTcO4.

A detailed variable temperature neutron total scattering study of the potential nuclear waste matrix TlTcO4 was conducted. The long-range average structure of TlTcO4 undergoes an orthorhombic Pnma to tetragonal I41/amd phase transition below 600 K, consistent with previous synchrotron X-ray diffraction studies. However, several anomalies were observed in the Rietveld refinements to the neutron powder diffraction data, such as large atomic displacement parameters at low temperature and a shortening of the Tc-O bond distance upon heating. Modelling the short-range local structure of both the low- and high-temperature data required a lowering of symmetry to the monoclinic P21/c model due to the stereochemical activity of the Tl+ 6s2 lone pairs. Density functional theory calculations also verified this model to have a lower ground state energy than the corresponding long-range average structure. It is concluded that at low temperatures, the Tl+ 6s2 lone pairs are 'frozen' into the structure. Upon heating, the rigid TcO4 tetrahedra begin to rotate, as governed by the Γ3+ and M4+ modes. However, there is a disconnect between the two length scales, with the 6s2 lone pair electrons remaining stereochemically active on the local scale, as observed in the neutron pair distribution function fits. The orthorhombic Pnma to tetragonal I41/amd phase transition is seemingly the result of a change in the correlation length of the Tl+ 6s2 lone pairs, leading to a larger unit cell volume due to their uncorrelated displacements.

Vibrational mode tailoring approach: an efficient route to compute anharmonic molecular vibrations of large molecules.

In this study, an efficient route to compute the multidimensional potential energy surfaces (PESs) for the description of quantum anharmonic molecular vibrations is presented. For large molecular systems, where the number of inter mode coupling terms are substantial, a tailor-made construction of truncated PESs is suggested which suitably avoids computation of full PESs by quantitative assessment of the atomic displacements during the normal mode of vibrations. It is shown that, typically, when two normal modes of vibrations are sharing the same atoms, the mode-mode coupling strength is generally large and can be included for truncated PESs. Since the calculations of these terms are the main computational bottleneck, the guided construction of tailor-made PESs can remarkably speed up the calculation by many folds against the expense of little accuracy for peak positions and intensities. This protocol is applicable to any anharmonic vibrational algorithm and more appropriate for large molecules where exploration of chemically important small fragments is more significant compared to that of the entire molecule. A systematic study for n-butanol and a dipeptide in the framework of the VSCF-PT2 method shows that for a group of n target modes, inclusion of a set of 5n-6n other associated important modes is sufficient to offer good accuracy with an error of ∼5-20 cm-1 against the full PES and computationally faster by ∼10-20 times. Finally, a prescription is given on the choice of such tailor-made PESs to compute anharmonic vibrational spectra accurately and efficiently without calculating the full PES.

Atomistic Simulation of Primary Radiation Damage Profiles in Fluorine-Doped Tin Oxide Thin Film Target Using SRIM Code

In this study, we investigated the discrepancy between the numbers of atomic displacements obtained from the Vac.txt method and those obtained from the Vac.dam method using SRIM-2013 operated in full cascade mode. The SRIM simulations also calculated energy partitioning, damage dose and distribution profiles of the implanted He, C and O ions at three different ion energies of 10 keV, 100 keV and 1 MeV. In all the simulations and at each ion energy value, the target thickness was increased until the entire ion beam was absorbed within the target. The simulated fluorine-doped tin oxide (FTO) thin film target stoichiometrically comprised 78.6% Sn, 16.4% O and 5.0% F, and a 6.013 g/cm3 bulk density. To achieve relatively good statistics with compromised computational time, each run followed 10 000 ion histories. The results indicated that, with increasing ion energies, the peaks of vacancy concentrations moved deeper into the material. For He ions, the vacancy profiles have peaks at ∼0.04, ~0.45 and ~2.9 µm at 10 keV, 100 keV and 1 MeV, respectively. Meanwhile, for C and O ions, the peaks were at ∼0.012, ~0.15 and ~1.23 µm for C ions and ∼0.01, 0.12 and 1.2 µm for O ions at 10 keV, 100 keV and 1 MeV, respectively. We also observed that for all the ions and at all ion energies considered, the Vac.txt method predicted more vacancies than the Vac.dam method, and the discrepancies generally increased with increasing Z by an average value of ∼1.21, ∼1.45 and 1.48 for He, C and O ions respectively. In addition, the electronic and nuclear partitioning profiles revealed that most of the energies of the ions were lost in collision with atomic electrons due to ionisation and excitations, and little to nuclear events. The simulations also revealed that nuclear stopping powers increase at low ion energies. This study also indicated that damage dose profiles strongly depend on the type of incident particle and its energy. A comparison of SRIM and iradina calculated vacancies and incident ion distribution profiles generally indicated perfect agreements between the two codes. FTO thin film remains a promising material for thermal control applications in future spacecraft. However, further analyses are still necessary to comprehensively understand its evolution under intense radiation environments comprising various ions and at different energies.

Local structural disorder introduced by Cr in fcc high-/medium-entropy alloys consisting of 3d transition metal elements

High-/medium-entropy alloys (H/MEAs) have attracted attention for their excellent mechanical properties. According to first-principles calculations, the atomic displacements from their lattice points are element-dependent and correlated with the yield strength of H/MEAs. To investigate experimentally the element dependence of the local structure, we measured the extended x-ray absorption fine structure in seven kinds of face-centered cubic H/MEAs consisting of 3d transition metal elements. Our experimental results indicate that the local disorder around chromium (Cr) is larger than that around other elements, which is a common feature in all the measured fcc H/MEAs, aligning with prior theoretical studies indicating larger displacements of Cr in comparison to other elements. We discuss the mechanism underlying the local structural disorder induced by the constituent element Cr.

Highly Tunable Moiré Superlattice Potentials in Twisted Hexagonal Boron Nitrides.

Moiré superlattice of twisted hexagonal boron nitride (hBN) has emerged as an advanced atomically thin van der Waals interfacial ferroelectricity platform. Nanoscale periodic ferroelectric moiré potentials in twisted hBN allow the hosting of remote Coulomb superlattice potentials to adjacent 2D materials. Therefore, the new strategies for engineering moiré length, angle, and potential strength are essential for developing programmable quantum materials. Here, it demonstrates the realization of twisted hBN-based moiré superlattice platforms and visualizes the moiré domains and ferroelectric properties using Kelvin probe force microscopy (KPFM). Also, the regular moiré superlattice in the large area is reported. It offers the possibility to reproduce uniform moiré structures with precise control piezo stage stacking and heat annealing. It demonstrates cumulative multi-ferroelectric polarization and multi-level domains with multiple angle mismatched interfaces. Additionally, it observes the quasi-1D anisotropic moiré domains and show the highest resolution analysis of the local built-in strain between adjacent hBN layers compared to the conventional methods. Furthermore, in-situ manipulation of moiré potential is demonstrated using femtosecond pulse laser, which results in the optical phonon-induced atomic displacement at the hBN moiré interfaces. The results pave the way to develop precisely programmable moiré superlattice platforms and investigate strongly correlated physics.

Temperature and Pressure Effects on Phase Transitions and Structural Stability in CsPb2Br5 and CsPb2Br4I Perovskite-Derived Halides.

All-inorganic perovskites exhibit outstanding light absorption properties in the visible range suitable for solar energy applications. We focus on the synthesis of CsPb2(Br,I)5 using mechanochemical procedures. Synchrotron X-ray diffraction (SXRD) data are essential for determining the crystallographic evolution in the 295-753 K temperature range. From room temperature to 573 K, the crystal structure is refined in a two-dimensional (2D) tetragonal framework (space group: I4/mcm) consisting of layers of face sharing [Pb(Br,I)8] polyhedra. Above a transition temperature of Tt = 630 and 621 K, identified from differential scanning calorimetry (DSC) curves for CsPb2Br5 and CsPb2Br4I, respectively, a cubic three-dimensional (3D) corner-sharing perovskite structure is identified, showing substantial Cs and (Br,I) deficiency. A more ionic character for Cs-halide versus Pb-halide is derived from the evolution of the anisotropic atomic displacements. An ultralow thermal conductivity of 0.35-0.18 W m-1 K-1 is related to the low Debye temperatures. From high-pressure SXRD studies, the change in B0 can be attributed to a basic expansion of the unit-cell volume caused by the chemical pressure from iodine within the CsPb2Br5 framework. UV-vis-NIR spectroscopy revealed optical gaps of approximately 2.93 and 2.50 eV, respectively, which agrees with ab initio calculations.

Point-defect-induced electronic polarization to enhance H* generation for removal of bisphenol A

Intrinsic point defects in metal core-shell materials can regulate electron redistribution, thereby reducing catalytic energy barriers and enhancing their ORR activity. However, their specific contributions to electron transfer and mass transport pathways remain unclear. In this study, defect-rich hollow OCo@Co3O4 nanoparticles were successfully synthesized using ZIF-67(Co) as a sacrificial template through controlled annealing and internal electric field substitution reactions. High-resolution electron microscopy analysis and density functional theory (DFT) calculations co-revealed the growth mechanism of Co and O vacancies, as well as antisite defects. The formation of oxygen vacancies significantly lowered the energy barrier for Co vacancy formation, playing a crucial bridging role in the development of antisite defects. The electric field polarization induced by Co-O atomic displacement resulted in asymmetric charge distribution, optimizing the adsorption of active hydrogen (H*) and oxygen atoms and facilitating the generation and release of reactive oxygen species (ROS). Electrocatalytic experiments demonstrated that under the combined action of singlet oxygen (1O2) and H*, bisphenol A (BPA) can be efficiently degraded. This study successfully bridges the knowledge gap between atomic defects and advanced electrocatalysis, providing a new perspective and insight for the in-depth analysis of the structure-performance relationship of electrocatalyst materials in the future.

Imprinted atomic displacements drive spin–orbital order in a vanadate perovskite

AbstractPerovskites with the generic composition ABO3 exhibit an enormous variety of quantum states, such as orbital order, magnetism and superconductivity. Their flexible and comparatively simple structure allows for straightforward chemical substitution and cube-on-cube combination of different compounds in atomically sharp epitaxial heterostructures. Many of the diverse physical properties of perovskites are determined by small deviations from the ideal cubic perovskite structure, which are challenging to control. Here we show that directional imprinting of atomic displacements in the antiferromagnetic Mott insulator YVO3 can be achieved by depositing epitaxial films on different facets of the same isostructural substrate. These facets were chosen such that other well-known control parameters, including lattice and polarity mismatch with the overlayer, remain nearly unchanged. We observe signatures of staggered orbital and magnetic order and demonstrate distinct spin–orbital ordering patterns on different facets. We attribute these results to the influence of specific octahedral rotation and cation displacement patterns, which are imprinted by the substrate facet, on the covalency of the bonds and the superexchange interactions in YVO3. Our results show that substrate-induced templating of lattice distortion patterns constitutes a pathway for materials design beyond established strain-engineering strategies.

Imaging in-operando LiCoO2 nanocrystallites with Bragg coherent X-ray diffraction

Although the LiCoO2 (LCO) cathode material has been widely used in commercial lithium ion batteries (LIB) and shows high stability, LIB’s improvements have several challenges that still need to be overcome. In this paper, we have studied the in-operando structural properties of LCO within battery cells using Bragg Coherent X-ray Diffraction Imaging to identify ways to optimise the LCO batteries’ cycling. We have successfully reconstructed the X-ray scattering phase variation (a fingerprint of atomic displacement) within a ≈ (1.6 × 1.4 × 1.3) μm3 LCO nanocrystal across a charge/discharge cycle. Reconstructions indicate strained domains forming, expanding, and fragmenting near the surface of the nanocrystal during charging, with a determined maximum relative lattice displacements of 0.467 Å. While discharging, all domains replicate in reverse the effects observed from the charging states, but with a lower maximum relative lattice displacements of 0.226 Å. These findings show the inefficiency-increasing domain dynamics within LCO lattices during cycling.

Hydrogen diffusion mechanisms in the 4130X steel: An integrated study with electrochemical experiments and molecular dynamics simulations

In this work, hydrogen diffusion behavior and mechanisms in the 4130X steel influenced by temperature, locally high concentration, and grain boundary were studied by leveraging both electrochemical hydrogen permeation experiments and molecular dynamics simulations. It was revealed that the hydrogen diffusion coefficient of the 4130X steel was increased with increasing temperature and decreasing locally high hydrogen concentration. The grain boundaries with misorientation below 15° characterized by an electron backscatter diffraction map were identified as hydrogen trapping sites, thus rendering a lower mean square displacement of hydrogen atoms and localized hydrogen diffusion trajectories. Furthermore, at a high hydrogen concentration of 4 at. %, these grain boundaries were saturated by hydrogen atoms, and platelet-like hydrogen clusters were formed within the lattice, which further inhibited the diffusive motion of hydrogen atoms. These findings would deepen our understanding of hydrogen embrittlement mechanisms by establishing the connections between macroscopic permeation behavior and atomic-scale hydrogen diffusion in structural materials.

Dissymmetrization in eudialyte-group minerals. I. A model of ordered cation arrangement in the crystal structure of amableite-(Ce) using the P3 symmetry

The crystal structure of the recently discovered eudialyte group mineral, amabellite-(Ce) Na15[(Ce1.5Na1.5)Mn3]Mn2Zr3£Si[Si24O69(OH)3](OH)2 · H2O, found in the hyperagpaitic pegmatite of the Saint-Amable massif (Canada), has been solved by X-ray structural analysis within the space group R3. Amabellite-(Ce) is a member of the eudialyte group with the lowest calcium content and differs from other members of this group by the dominance of lanthanides in the part of the edge-sharing octahedra of the six-membered ring. The unit cell parameters of the mineral are: a = 14.1340(2), c = 30.378(1) Å, V = 5255.6(3) ų. A model of the cation distribution in the crystal structure of amabellite-(Ce) within the low-symmetry space group P3 has been proposed. The obtained 162 independent positions were refined in the isotropic-anisotropic approximation of atomic displacements using 3968 F 3σ(F), R = 4.6%. Despite the fairly close results, the transition from space group R3 to P3 allows for more detailed information on the local distribution of a number of elements over the framework positions. A comparison was made between the crystal structure models of amabellite within the symmetries R3 and P3, as well as other low-calcium eudialyte group minerals previously studied within several space groups.

Theoretical investigations on exploring Si-based heterostructures with cubic and ground-state perovskites

First principles calculations in the framework of density functional theory (DFT) are performed to exploit replaceable perovskite oxides against the instability of traditional cubic SrTiO3 grown on silicon substrate. In this work, we consider more thermostable CaTiO3 and CaZrO3 with cubic and ground-state phase as the candidates to perform the gate dielectric. After the calibration of total energy and lattice transformation of ground-state perovskites to match with Si substrate, three categories of 2 × 2 heterostructures have been constructed and investigated through the geometrical change, atom displacement around interfacial layer, total energy and electronic structure change, under the variations on perovskite species, the concentration of interfacial layer and the thickness of perovskite film. And the results demonstrate that the category with half a monolayer of Ca/Sr atoms in interfacial layer and two unit-cell perovskite thicknesses show the type-I band alignment through their band alignment. Among this category, the heterostructure with Pnma CaZrO3 shows semiconductivity and excellent electrical property with larger band offset for the candidate of gate dielectric. This work provides a creative perspective to expand the perovskite diversity for the booming growth of integrated circuit technology.

Boosting Energy-Storage in High-Entropy Pb-Free Relaxors Engineered by Local Lattice Distortion.

The high-entropy strategy has shown potential in advancing the energy-storage performance of dielectric capacitors, offering benefits to a range of electronic and electrical systems. However, designing high-performance high-entropy relaxor ferroelectrics (RFEs) presents challenges due to the unclear correlation between their core effects and local polarization heterogeneity. Here, we demonstrate that by engineering the local lattice distortion, a core effect in high-entropy systems, to manipulate the local polarization configuration, a giant energy density (Wrec) of 18.7 J cm-3 and high efficiency (η) of 85% can be achieved in (Bi0.5K0.5)TiO3-based high-entropy bulk RFE ceramics. Atomic-level local structural analysis unveils that the local lattice distortion field can be flattened by introducing ions with less size mismatch. The increase in configurational entropy from 1.54 to 2.06R is associated with a smoother polar displacement vector field and a reduction in the size of polar clusters to several unit-cell sizes with weak coupling. Consequently, a substantial decrease in hysteresis and an enhancement in the breakdown field strength can be obtained, leading to a significant improvement in energy density by over 6 times and efficiency by 3 times. Our research establishes a relationship between local lattice distortion, atomic polar displacement, and energy-storage performance in complex high-entropy systems, providing insights for enhancing energy-storage performance via a local structure design.

Understanding secondary order parameters in perovskites with tilted octahedra

In the family of perovskite materials, the tilts of BX 6 octahedra are the most common type of structural distortion. Conventionally, the formation of low-symmetry perovskite phases with tilted octahedra is analyzed by considering only primary order parameters. However, octahedral tilting also gives rise to secondary order parameters which contribute to additional atomic displacements, ordering and lattice distortions. Our study highlights the significant impact of secondary order parameters on the structural formation and emergent physical properties of perovskites. Through group-theoretical and crystallographic analyses, we have identified all secondary order parameters within Glazer-type tilt systems and clarified their physical manifestations. We explore the fundamental symmetry relationships among various structural degrees of freedom in perovskites, including tilt-induced ferroelasticity, correlations between displacements and ordering of atoms occupying different positions, and the potential for rigid unit rotations and unconventional octahedral tilts. Particular emphasis is placed on the emergence of secondary order parameters and their coupling with primary order parameters, as well as their symmetry-based hierarchy, illustrated through a modified Bärnighausen tree. We applied our theoretical insights to elucidate phase transitions in well known perovskites such as CaTiO3 and RMnO3 (where R = La and lanthanide ions), thereby demonstrating the significant influence of secondary order parameters on crystal structure formation. Our results serve as a symmetry-based guide for the design, identification and structural characterization of perovskites with tilted octahedra, and for understanding tilt-induced physical properties.

Dynamic Evolution of Local Atomic Environments in a Cu66Zr34 Bulk Metallic Glass

This study presents a molecular dynamics (MD) investigation of the evolution of local atomic environments (LAEs) in a Cu66Zr34 bulk metallic glass (BMG), both at rest and under constant shear deformation. LAEs were characterized using Voronoi polyhedra analysis. Even in the absence of external load, LAEs frequently transformed into one another due to short-ranged atomic position fluctuations. However, as expected, each transition from one polyhedra to another was balanced by the reverse transition, thereby preserving the proportions of the different polyhedra. Cu-centered icosahedral LAEs were observed to preferentially transform into and from <1,0,9,3,0>, <0,1,10,2,0>, and <0,2,8,2,0> LAEs. Upon applying pure shear, the simulation box was first deformed in one direction up to a strain of 25% and then in the opposite direction to the same strain level. Shear deformation induced large nonaffine atomic displacements in the directions parallel to the shear, which were concentrated in specific regions of the BMG, forming band-like regions. From the onset, shear deformation led to the destabilization of Cu-centered icosahedral LAEs, as indicated by more frequent transitions to and from other polyhedra. Unlike other Cu-centered LAEs, icosahedra were also found to be more sensitive to yielding. The destruction of Cu-centered icosahedra was primarily a result of net transformations into <1,0,9,3,0> and <0,2,8,2,0> LAEs in the BMG subjected to pure shear, with a minor contribution of transformations involving the <0,1,10,2,0> polyhedra.

Electron Irradiation on Metal Oxide Silicon Field Effect Transistors in Space Applications

The space environment is hostile to most semiconductor electronic devices and components used for space applications. The radiation generally encountered in space are α, β, γ, x-ray, energetic electrons, protons, neutrons and ions of various kinds. Especially the Van Allen Belts consist of high energy electrons which are in continuous motion. Satellites systems operating in Low Earth Orbits (LEO) are prone to get exposed to high energy electrons. This paper describes the effect of electron beam irradiation on MOSFETs planned for space applications. The devices selected for the study are 2N6768 n- channel MOSFETs (JANTXV) procured from ISAC, Bangalore. The decapped MOSFETS are exposed to a beam of electrons for various doses ranging from 50 Gy to 10 KGy in the electron energy range 7 – 10 MeV using the electron accelerator facility at RRCAT, Indore. Pre and post- irradiation measurements of the electrical characteristics are undertaken to investigate the electron induced device degradation and damage. The dominant mechanism of the interaction of the electrons with semiconductors is to produce atomic displacement which can have serious impact on electrical characteristics. MOS (Metal oxide semiconductor) devices are the most sensitive of all semiconductor devices to radiation showing considerable degradation even for a relatively low dose of exposure to high energy electrons. The energy dissipated by electrons in semiconductors is sufficient to displace silicon atoms and causes a shift in the threshold voltage and leakage current. The study indicates that the gate threshold voltage substantially decreases with the increase in electron dose. The leakage current increases with dose which could have an impact on the performance of the device. The transconductance of the MOS transistor is found to decrease with increase in electron dose. The observed changes in the electrical characteristics upon electron irradiation are analysed and interpreted as due to trapped charges in the SiO2 layer and at the interface. The present investigation reveals that there is a remarkable degradation in threshold voltage and the leakage current displays substantial increase when the devices are exposed to electrons. This increase in leakage current can have significant impact on device performance in a radiation environment.