Organic thin film transistors: Materials, processes and devices

Tetracene Based OTFT with Nd₂O₃-dielectric Layer

“…The increase in current with the negative gate voltage indicates field-effect-induced hole conduction, which is the expected behaviour for tetracene. The theoretical equation for drain current (I D ) is [13]:…”

“…The channel conductivity σ is estimated from the plot of I D vs. V D graph at zero gate voltage. The ON-OFF ratio is estimated from the following relation [13]:…”

Electrical conduction mechanisms in the transfer characteristics of pentacene thin film transistors

“…The carrier transport also occurs via hopping in the distribution of localized levels. 16 The conduction mechanism in the pentacene film is said to be hopping dominated, [17][18][19][20] where conduction occurs by charge carriers hopping through various hopping sites. The gate bias and temperature dependent field-effect mobility and the conductance of an OTFT are also analyzed, to study the charge transport in the material.…”

Submicron organic thin-film transistors fabricated by film profile engineering method

“…In this study, a thermal evaporator was employed for depositing the pentacene channel and a major consideration on the deposition pressure is raised. Deposition of evaporators is usually set in the range from 10 À6 to 10 À5 Torr, 11 much lower than that of the sputter deposition ($mtorr). Such a low pressure may hinder the formation of a continuous layer, as the scattering probability in the chamber is too small to affect the directionality of the deposition species.…”

“…To further improve the performance of OTFTs, promoting the crystallinity of the channel film is feasible. This is achievable by performing a surface treatment on the gate dielectric to form self-assembled monolayers (SAM) 11 which provide an ordered template for subsequent channel film deposition. It is expected that the performance of FPE OTFTs will be improved considerably if the above SAM process procedure is implemented.…”