Pentacene-carbon nanotubes: Semiconducting assemblies for thin-film transistor applications

Abstract

We demonstrate an alternative path for achieving high-transconductance organic transistors by assembling bilayers of pentacene onto random arrays of single-walled carbon nanotubes. We show here that, by varying the connectivity of the underlying nanotube network, the channel length of a thin-film transistor can be reduced by nearly two orders of magnitude—thus, enabling the increase of the device transconductance without reduction the on/off ratio. These field-induced percolating networks enable assembling high-transconductance transistors that, with relatively large source drain distances, can be manufactured with available commercial printing techniques.

Semiconductor behaviors of low loading multiwall carbon nanotube/poly(dimethylsiloxane) composites

“…It increases with increasing drain voltages, and approaches 8.34ϫ 10 −8 S at V ds = 2.5 V. This value is larger than that in pentacene TFT ͑2.48ϫ 10 −8 S at V ds =5 V͒, and comparable to pentacene/SWNT TFT ͑typicallyϳ 1 ϫ 10 −7 S at V ds =5 V͒. 3 These results suggest that MWNT/PDMS composite is a promising material for flexible electronics.…”

“…Using the standard formula eff = dI ds / dV g L ox L ds / ͑V ds W ds ͒, where L ox and are the thickness and dielectric constant of the SiO 2 layer, we calculate the effective mobility of the device to be 1.98 cm 2 V s at V ds = 2.5 V. This value compares favorably to that derived from a-Si thin film transistors ͑TFTs͒, where =1 cm 2 V s is typical, 15 and is about 1-2 orders higher than that of organic semiconductors ͑on the order of 0.01-0.1 cm 2 V s͒. 3,16 It is also slightly higher than the effective mobility of SWNT/organic semiconductor TFTs ͑typicallyϽ 1 cm 2 V s͒, 2-4 yet generally lower than that of pristine SWNT networks TFTs ͑on the order of 10 cm 2 V s͒. 17,18 From Fig.…”

Höhere Acene: vielseitige organische Halbleiter

“…[236] Die Abscheidung einwandiger Nanoröhren im Transistorkanal steigert die Beweglichkeit der Ladungsträger. Dabei wird die Konzentration an Nanoröhren begrenzt, damit sich kein durchgängiges Netzwerk bildet und um Kurzschlüsse zu vermeiden; [237] anschließend wird darauf eine Pentacenschicht abgeschieden (Abbildung 21). Die Beweglichkeiten waren bei diesem Vorgehen ungefähr dreimal so hoch wie ohne Nanoröhren.…”

High‐Performance, Vertical‐Type Organic Transistors with Built‐In Nanotriode Arrays

“…Therefore, it can be said that organic SITs with nanotriode arrays have an advantage in engineering of device characteristics by using, for example, semiconductor device simulation, as solid-state physics inside the semiconductor layer plays a major role in device operation. Several other devices with good performance in terms of large g m [25] or low driving voltages [2,[26][27][28][29][30][31][32] have been reported. However, large-g m devices need high driving voltages, and low-voltage devices cannot support a large drain-source current.…”