High-Performance Flexible Single-Crystalline Silicon Nanomembrane Thin-Film Transistors with High‑k Nb2O5–Bi2O3–MgO Ceramics as Gate Dielectric on a Plastic Substrate
journal contributionposted on 22.03.2018, 00:00 by Guoxuan Qin, Yibo Zhang, Kuibo Lan, Lingxia Li, Jianguo Ma, Shihui Yu
Any type of content formally published in an academic journal, usually following a peer-review process.
A novel method of fabricating flexible thin-film transistor based on single-crystalline Si nanomembrane (SiNM) with high-k Nb2O5–Bi2O3–MgO (BMN) ceramic gate dielectric on a plastic substrate is demonstrated in this paper. SiNMs are successfully transferred to a flexible polyethylene terephthalate substrate, which has been plated with indium-tin-oxide (ITO) conductive layer and high-k BMN ceramic gate dielectric layer by room-temperature magnetron sputtering. The BMN ceramic gate dielectric layer demonstrates as high as ∼109 dielectric constant, with only dozens of pA current leakage. The Si–BMN–ITO heterostructure has only ∼nA leakage current at the applied voltage of 3 V. The transistor is shown to work at a high current on/off ratio of above 104, and the threshold voltage is ∼1.3 V, with over 200 cm2/(V s) effective channel electron mobility. Bending tests have been conducted and show that the flexible transistors have good tolerance on mechanical bending strains. These characteristics indicate that the flexible single-crystalline SiNM transistors with BMN ceramics as gate dielectric have great potential for applications in high-performance integrated flexible circuit.