Substrate Mediated Synthesis of Ti–Si–N Nano‐and‐Micro Structures for Optoelectronic Applications

Abstract

Being one of the strongest materials, ternary TiSiN exhibits a very interesting family of binary transition metal nitride and silicide systems. A novel technique to fabricate morphologically fascinating nano and micro structures of TiSiN is reported here. The referred TiSiN films, majorly constituted with cubic TiN phase, are enriched with crystalline nanoparticles, microflowers and faceted micro-crystals which possess attractive functionalities towards plasmon mediated optoelectronic applications. Reactivity of titanium to silicon nitride based dielectric topping on the substrate at high temperature plays the key role in nitride formation for the demonstrated protocol. The optoelectronic response for these morphologically enriched composite films indicates an influential role of photo-induced surface plasmon polaritons (SPPs) on their dc transport properties. A plasmonically tuned resistive switching, controlled by the surface morphology in association with the film thickness, is observed under light illumination. Using Drude's modified frequency dependent bulk electron scattering rates and surface mediated SPPs-electron scattering rates, a generic model is proposed for addressing unambiguously the increased device resistance in response to light. The featured synthesis process opens a new direction towards the growth of transition metal nitrides while the proposed model serves as a basic platform to understand photo-induced electron scattering mechanisms in metal. annealing of Si/Ti/Si based thin film tri-layers on Si 3 N 4 /Si (100) substrate, one can successfully fabricate crystalline nanoparticles, faceted micro-crystals, and crystalline microflowers on Ti-Si-N based nanostructured composite film (NCF) which are predominantly occupied with cubic fcc-phased nano and micro structures of TiN, [1] Coupling with optical excitation in the visible and NIR wavelength range, the Ti-Si-N based NCFs having devices on top exhibit surface morphology dependent anomalous photo-response which shows switching to a highly resistive state.Recently, there are many reports of negative photoconductivity (NPC) observed in materials like semiconducting nanostructures, [25][26][27] topological insulators, [28] graphene based composite systems, [29][30][31] metallic nanostructures [32][33][34][35] etc. Trapping of photo-excited electrons by localized trapped states, [36] band gap opening, [28] e-SPPs scattering mechanisms [32] are commonly used to address the origin of the NPC. However, if a generic model were available to understand the origin of NPC particularly for metallic systems, the performance could be tuned in a preferable way by controlling the morphology. Considering the possible scattering mechanisms for the conduction electrons, we introduce a simple but competent model primarily constituted with frequency dependent bulk electron scattering rate and surface mediated scattering of electrons with photo-induced SPPs [32] . The observed NPC, controlled by the morphology induced SPPs and the film thickness, can be justified a...

Probing electron-electron interaction along with superconducting fluctuations in disordered TiN thin films

“…Ti thin film deposited substrates were annealed at different annealing temperatures of about (820C, 780C & 750C) for 2 hours at a pressure less than 5 x 10 -8 Torr. During the annealing process, Ti transformed into TiN by the substrate mediated nitridation technique [18][19][20][21] where…”

Interface study of thermally driven chemical kinetics involved in Ti/Si3N4 based metal-substrate assembly by X-ray photoelectron spectroscopy

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Granularity mediated multiple reentrances with negative magnetoresistance in disordered TiN thin films

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