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  • Published Article: Expeditious, scalable solution growth of metal oxide films by combustion blade coating for flexible electronics
Title: Expeditious, scalable solution growth of metal oxide films by combustion blade coating for flexible electronics

Metal oxide (MO) semiconductor thin films prepared from solution typically require multiple hours of thermal annealing to achieve optimal lattice densification, efficient charge transport, and stable device operation, presenting a major barrier to roll-to-roll manufacturing. Here, we report a highly efficient, cofuel-assisted scalable combustion blade-coating (CBC) process for MO film growth, which involves introducing both a fluorinated fuel and a preannealing step to remove deleterious organic contaminants and promote complete combustion. Ultrafast reaction and metal–oxygen–metal (M-O-M) lattice condensation then occur within 10–60 s at 200–350 °C for representative MO semiconductor [indium oxide (In2O3), indium-zinc oxide (IZO), indium-gallium-zinc oxide (IGZO)] and dielectric [aluminum oxide (Al2O3)] films. Thus, wafer-scale CBC fabrication of IGZO-Al2O3thin-film transistors (TFTs) (60-s annealing) with field-effect mobilities as high as ∼25 cm2V−1s−1and negligible threshold voltage deterioration in a demanding 4,000-s bias stress test are realized. Combined with polymer dielectrics, the CBC-derived IGZO TFTs on polyimide substrates exhibit high flexibility when bent to a 3-mm radius, with performance bending stability over 1,000 cycles.
Authors:
; ; ; ; ; ; ; ; ; ; ; ; ; ;
Publication Date:
NSF-PAR ID:
10091784
Journal Name:
Proceedings of the National Academy of Sciences
Page Range or eLocation-ID:
Article No. 201901492
ISSN:
0027-8424
Publisher:
Proceedings of the National Academy of Sciences
Sponsoring Org:
National Science Foundation
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