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Title: Role of atomic migration in nanocrystalline stability: Grain size and thin film stress states

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Journal Article: Publisher's Accepted Manuscript
Journal Name:
Current Opinion in Solid State and Materials Science
Additional Journal Information:
Journal Volume: 19; Journal Issue: 2; Related Information: CHORUS Timestamp: 2016-09-04 08:14:55; Journal ID: ISSN 1359-0286
Country of Publication:
United Kingdom

Citation Formats

Kapoor, Monica, and Thompson, Gregory B. Role of atomic migration in nanocrystalline stability: Grain size and thin film stress states. United Kingdom: N. p., 2015. Web. doi:10.1016/j.cossms.2014.11.001.
Kapoor, Monica, & Thompson, Gregory B. Role of atomic migration in nanocrystalline stability: Grain size and thin film stress states. United Kingdom. doi:10.1016/j.cossms.2014.11.001.
Kapoor, Monica, and Thompson, Gregory B. 2015. "Role of atomic migration in nanocrystalline stability: Grain size and thin film stress states". United Kingdom. doi:10.1016/j.cossms.2014.11.001.
title = {Role of atomic migration in nanocrystalline stability: Grain size and thin film stress states},
author = {Kapoor, Monica and Thompson, Gregory B.},
abstractNote = {},
doi = {10.1016/j.cossms.2014.11.001},
journal = {Current Opinion in Solid State and Materials Science},
number = 2,
volume = 19,
place = {United Kingdom},
year = 2015,
month = 4

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.1016/j.cossms.2014.11.001

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Cited by: 5works
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  • Abstract not provided.
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  • Solution-processed ultra-thin (∼3 nm) zinc tin oxide (ZTO) thin film transistors (TFTs) with a mobility of 8 cm{sup 2}/Vs are obtained with post spin-coating annealing at only 350 °C. The effect of light illumination (at wavelengths of 405 nm or 532 nm) on the stability of TFT transfer characteristics under various gate bias stress conditions (zero, positive, and negative) is investigated. It is found that the ΔV{sub th} (V{sub th}{sup stress} {sup 3400} {sup s − stress} {sup 0} {sup s}) window is significantly positive when ZTO TFTs are under positive bias stress (PBS, ΔV{sub th} = 9.98 V) and positive bias illumination stress (λ = 405 nm and ΔV{sub th} = 6.96 V), butmore » ΔV{sub th} is slightly negative under only light illumination stress (λ = 405 nm and ΔV{sub th} = −2.02 V) or negative bias stress (ΔV{sub th} = −2.27 V). However, the ΔV{sub th} of ZTO TFT under negative bias illumination stress is substantial, and it will efficiently recover the ΔV{sub th} caused by PBS. The result is attributed to the photo-ionization and subsequent transition of electronic states of oxygen vacancies (i.e., V{sub o}, V{sub o}{sup +}, and V{sub o}{sup ++}) in ZTO. A detailed mechanism is discussed to better understand the bias stress stability of solution processed ZTO TFTs.« less
  • With a wide variety of applications in numerous industries ranging from bio-medical to nuclear, ceramics such as ceria are key engineering materials. It is possible to significantly alter the materials functionality and therefore its applications by reducing the grain size to the nanometer size regime, at which point the unique varieties of grain boundaries and associated interfaces begin to dominate the material properties. Nanocrystalline films of cubic ceria deposited onto Si substrates have been irradiated with 3 MeV Au+ ions at temperatures of 300 and 400 K to evaluate their response to irradiation. It was observed that the films remainedmore » phase stable. Following a slight stress relief stage at low damage levels, the overall lattice is extremely stable up to high irradiation dose of {approx} 34 displacements per atom (dpa). The grains were also observed to undergo a temperature dependent grain growth process upon ion irradiation. This is attributed to a defect-driven mechanism in which the diffusion of defects from the collision cascade is critical. Formation of dislocations that terminate and stabilise at symmetric grain boundaries may be the limiting factor in the grain growth and overall energy reduction of the system. Utilizing ion modification, possible improvement of the adhesion of thin films and reduction of the probability of detrimental effects of stress-induced problems are discussed.« less