Ultralow voltage operation of biologically assembled all carbon nanotube nanomesh transistors with ion-gel gate dielectrics.

The demonstration of field-effect transistors (FETs) based entirely on single-walled carbon nanotubes (SWNTs) would enable the fabrication of high-on-current, flexible, transparent and stretchable devices owing to the excellent electrical, optical, and mechanical properties of SWNTs. Fabricating all-SWNT-based FETs via simple solution process, at room temperature and without using lithography and vacuum process could further broaden the applicability of all-SWNT-FETs. In this work, we report on biologically assembled all SWNT-based transistors and demonstrate that ion-gel-gated network structures of unsorted SWNTs assembled using a biological template material enabled operation of SWNT-based transistors at a very low voltage. The compatibility of the biologically assembled SWNT networks with ion gel dielectrics and the large capacitance of both the three-dimensional channel networks and the ion gel allowed an ultralow operation voltage. The all-SWNT-based FETs showed an I /I value of >10, an on-current density per channel width of 2.16 × 10 A/mm at V = 0.4 V, and a field-effect hole mobility of 1.12 cm/V · s in addition to the low operation voltage of <-0.5 V. We envision that our work suggests a solution-based simple and low-cost approach to realizing all-carbon-based FETs for low voltage operation and flexible applications.