Photonic conversion of sol-gel organometallic precursors into inorganic thin films

Tools

Koutsiaki, C., 2023. Photonic conversion of sol-gel organometallic precursors into inorganic thin films. PhD, Nottingham Trent University.

Preview

Text
Christina Koutsiaki 2023.pdf - Published version
Download (3MB) | Preview

Abstract

Large area electronics manufacturing has been emerged over this last decade to become an exciting and yet challenging field of interest. The realisation of large-scale fabrication of high performance electronics is achieved via a solution-processing based manufacturing scheme that is compatible to high-throughput fabrication systems. Metal oxides (MOs) constitute an attractive, highly promising candidate towards delivering trend-of-future applications, with their enhanced electronic properties, mechanical stability and optical transparency establishing them as a unique tool. The realisation of MO thin films via the solution processes such as "sol-gel" is employed through the conversion of metalorganic precursor films into MOs. To tackle the demanding post-deposition annealing treatments of precursor films in high-temperatures, laser annealing (LA) has been proposed as a propitious alternative, as its unique characteristic of localised, high-temperature induction that is able to deliver a successful precursor conversion within a few nanoseconds. This research sought to tackle two principal challenges that accompany the fabrication of MO thin films via sol-gel and LA: the first challenge concerned the difficulty of monitoring the conversion process of ultra-thin films (~10 nm) with non-invasive characterisation tools and was overcome using infrared spectroscopic ellipsometry (IRSE). To the best of our knowledge, this work comprised the pioneering investigation of the potential of IRSE in delivering a detailed overview of the conversion steps by detecting the associated byproducts. More importantly, the challenge implied by the low film thickness, as required for electronic devices, was tackled by enhancing IRSE sensitivity using highly reflective substrates as well as proposing a comprehensive tool for testing the substrate sensitivity that is inherently tailored for each material of interest. The IRSE study thus provided vital information on the formation of In2O3 and ZnO films, which constituted the "seed" materials for overcoming the second core challenge of this research: the introduction of LA to the sol-gel process. LA was employed towards the fabrication of solution processed In2O3, IGZO, and ZnO thin films and their pre- and post-processed properties were analysed through their role as an active layer in TFT devices. SiO2 was employed as the device dielectric, with various SiO2 thicknesses constituting an additional parameter of study due to the thickness effect on the irradiation absorption for the surface films. This research objective was realised by expanding the material palette of laser processed and sol-gel fabricated MOs into dielectric films. Focus was given to the study of ZrO2, a promising dielectric candidate that had as-of-yet stood untested with LA. The manufacturing schemes of the resultant ZrO2 thin films were investigated, followed by their use as dielectrics in MO capacitor devices. Finally, all the attained knowledge was aggregated and applied it towards the fabrication of TFTs based entirely on laser-processed, sol-gel fabricated, and heterogeneously metal oxide dielectric and semiconductor thin films.

Item Type:

Thesis

Creators:

Koutsiaki, C.

Contributors:

Name	Role	NTU ID	ORCID
Koutsogeorgis, D.	Thesis supervisor	EEE3KOUTSD	orcid.org/0000-0001-6167-1084
Kalfagiannis, N.	Thesis supervisor	SST3KALFAN	orcid.org/0000-0002-4030-5525

Date:

March 2023

Rights:

The copyright in this work is held by the author. You may copy up to 5% of this work for private study, or personal, non-commercial research. Any re-use of the information contained within this document should be fully referenced, quoting the author, title, university, degree level and pagination. Queries or requests for any other use, or if a more substantial copy is required, should be directed to the author.

Divisions:

Schools > School of Science and Technology

Record created by:

Linda Sullivan

Date Added:

08 Nov 2023 08:59

Last Modified:

08 Nov 2023 08:59

URI:

https://irep.ntu.ac.uk/id/eprint/50311