Contact Resistance and Megahertz Operation of Aggressively Scaled Organic Transistors

Abstract

Bottom-gate, top-contact organic thin-film transistors (TFTs) with excellent static characteristics (on/off ratio: 10(7) ; intrinsic mobility: 3 cm(2) (V s)(-1) ) and fast unipolar ring oscillators (signal delay as short as 230 ns per stage) are fabricated. The significant contribution of the transfer length to the relation between channel length, contact length, contact resistance, effective mobility, and cutoff frequency of the TFTs is theoretically and experimentally analyzed.

Indacenodithiophene-benzothiadiazole organic field-effect transistors with gravure-printed semiconductor and dielectric on plastic

“…Here we refer to our extracted values as an effective mobility, as they are a convolution of both the intrinsic mobility of the material and also other effects, such as contact resistance which acts to lower the measured mobility. [26] With this conservative estimate, these results compare well with the previous report of Zhang et al [19] of μ ≈ 0.02 cm 2 V −1 s −1 for C 16 IDT-BT spin-coated on bottom-gate bottom-contact (BGBC) OFETs on a silicon substrate. Although lower than the performance reported for top-gate top-contact devices, our BGBC geometry facilitates self-alignment, with numerous other benefits.…”

Contact resistance and overlapping capacitance in flexible sub-micron long oxide thin-film transistors for above 100 MHz operation

“…5 Different forms of silicon, 6,7 carbon based materials like nanotubes or organic polymers and small molecules, [8][9][10] or amorphous semiconductors can be used to build such devices. 11,12 Deformable wireless sensors or bendable radio frequency transceivers require electronic circuits which operate in the megahertz regime in order to treat signals, and transmit data.…”

“…However, a deeper analysis of the TFT geometry reveals that, due to the carrier accumulation layer between gate and source/drain contacts in staggered TFTs, C OV and R C are not independent from each other and they both directly depend on L OV . 10,23 Here, we conduct a quantitative analysis based on a large number of flexible ultra-scaled IGZO TFTs. Flexible devices with three different values of overlap length and channel length down to 0.5 lm are fabricated to investigate the scaling behavior of the transit frequency.…”

Cellulose as biodegradable high-k dielectric layer in organic complementary inverters

“…1 In addition to the intense research on the development of high performance organic semiconductors, 2 special attention is directed towards improving the performance of the gate dielectric layer especially with respect to maximizing its capacitance without affecting its dielectric strength. Highcapacitance gate dielectrics are a necessity for high-speed small channel oTFTs operating at reasonably low voltage levels.…”