Faculty Publications

Permanent URI for this communityhttps://idr.nitk.ac.in/handle/123456789/18736

Publications by NITK Faculty

Browse

Author: search.filters.author.Rodney, J.D.Subject: search.filters.subject.Electrical switching

Search Results

Now showing 1 - 2 of 2
  • No Thumbnail Available
    Item
    Investigation of Indium doped Se-Te bulk chalcogenide glasses for electrical switching and phase changing applications
    (Elsevier Ltd, 2024) Joshi, S.; Rodney, J.D.; James, A.; Behera, P.K.; Udayashankar, N.K.
    Recently, Metal-doped Se-Te chalcogenides have gained a lot of interest due to their unique capacity for electrical switching, which makes them desirable for electronic applications. This study examines the electrical switching characteristics of bulk Se86−xTe14Inx (0 ≤ x ≤ 6) amorphous alloys produced by the conventional melt-mix-quench process. The samples with an Indium atomic percentage between 2 to 6 exhibited a remarkable transition from a highly resistive to a low resistive state when subjected to an electric field with a current of 1 mA, displaying quick and reversible switching behaviour. The threshold voltage (Vth) significantly dropped from 410.6 V to 49.2 V with an increase in Indium concentration. Additionally, above the specific current threshold, these bulk glasses demonstrated memory-type switching, demonstrating their potential for data storage applications. To comprehend the trend of glass forming ability, thermal stability range and Hruby's glass stability parameters, with their compositional dependency, Differential Scanning Calorimetry (DSC) was utilized. The sample Se80Te14In6 emerged to be the fastest phase-changing material, with a memory switching current threshold of Ith = 1.3 mA and a threshold voltage value of 49.2 V. To study the formation of crystallites in Se-Te-In alloy, X-ray diffraction patterns of pristine glass and the annealed sample were examined. Furthermore, temperature-dependent conductivity investigations showed a sharp rise in conductivity once the process crystallization begins (Tx), and also the threshold voltage (Vth) of the samples decreased linearly with rising temperature. Overall, this study provides valuable insights into the electrical switching behaviour and thermal properties of Se-Te-In chalcogenide glasses, enhancing their suitability in electronic devices. © 2024 Elsevier B.V.
  • No Thumbnail Available
    Item
    Peculiarities of Electrical Switching and Phase Transition Dynamics in Bismuth-Infused Se-Te Chalcogenide Glasses: From Bulk to Thin Film Devices
    (American Chemical Society, 2024) Joshi, S.; Rodney, J.D.; Udayashankar, N.K.
    Herein, the electrical switching behavior of both bulk and thin film forms of Se86-xTe14Bix (0 ≤ x ≤ 4) chalcogenide glasses was investigated. The melt-quench-derived glasses were found to be amorphous, and the switching behavior exhibited a threshold-type response below a certain current limit (Ith) for bismuth (Bi)-doped bulk samples. Interestingly, as current levels surpassed this threshold, a noteworthy change occurred in the switching behavior, converting it into a memory-type response. The threshold voltage (Vth) exhibited a decreasing trend from ∼228 V to ∼36 V with an increasing Bi content, and differential scanning calorimetry (DSC) was utilized to study the phase transition phenomena and thermal stability of the amorphous glasses. These DSC results unequivocally confirmed that the transition from amorphous to crystalline phase occurred readily and at lower temperatures in the Se82Te14Bi4 composition. Furthermore, annealing studies were carried out to gain insight into the phase transformations that occur when the material makes the transition from an amorphous to a crystalline state. Subsequently, the same melt-quench-derived glasses were deposited as a thin film using physical vapor deposition (PVD) into a three-layered Al/Se-Te-Bi/Al device, and the memory switching voltage experienced a remarkable drop to 2.88 V compared to the bulk material. This exploration sheds light on the captivating electrical switching behavior of Se86-xTe14Bix chalcogenide glasses and holds promise for potential applications spanning the realm of emerging electronics and phase change material (PCM) devices. © 2024 American Chemical Society.