Design of Novel Dielectric Surface Modifications for Perylene Thin‐Film Transistors

Abstract

Dielectric surface modifications (DSMs) can improve the performance of organic thin‐film transistors (OTFTs) significantly. In order to gain a deeper understanding of this performance enhancement and to facilitate high‐mobility transistors, perylene based devices utilizing novel dielectric surface modifications have been produced. Novel DSMs, based on derivates of tridecyltrichlorosilane (TTS) with different functional end‐groups as well as polymeric dielectrics have been applied to tailor the adhesion energy of perylene. The resulting samples were characterized by electronic transport measurements, scanning probe microscopy, and X‐ray diffraction (XRD). Measurements of the surface free energy of the modified dielectric enabled the calculation of the adhesion energy of perylene upon these novel DSMs by the equation‐of‐state approach. These calculations demonstrate the successful tailoring of the adhesion energy. With these novel DSMs, perylene thin‐films with a superior film quality were produced, which enabled high‐performance perylene‐based OTFTs with high charge‐carrier mobility.

A New Route to Low Resistance Contacts for Performance‐Enhanced Organic Electronic Devices

“…Comparing SAMs with different alkyl chains helps to elucidate the role of the DTC linker group in the electronic structure at the interface. Longer alkyl chains are known to affect surface energetics and wettabilities, and in turn these properties can influence the growth and ordering of semiconductor thin‐films deposited on metal electrodes modified with SAMs . All even‐numbered n,n ‐dialkyl dithiocarbamates (abbreviated CnDTC, where n is the number of methyl units) between n,n ‐diethyldithiocarbamate [(C 2 H 5 ) 2 NCSSH, C2DTC] and n,n ‐didecyldithiocarbamate [(C 10 H 21 ) 2 NCSSH, C10DTC] were studied.…”

Surface Infused Interpenetrating Network as Gate Dielectric for High Performance Thin Film Transistors

“…Furthermore, the adhesion energy of PDVT‐8 on IPN films and neat cross‐linked PVP are calculated that list in Table S1 in the Supporting Information. The adhesion energy between PDVT‐8 and IPN films is lower than neat cross‐linked PVP, which improves the surface wettability of dielectric layers with organic semiconductor solution . It is also worth to note that, as shown in Figure , those pinholes on the surface of PVP films are eliminated by IPN, which results in optimized surface roughness of dielectric/semiconductor interface and enhanced densification of PVP films.…”

“…Furthermore, the smoothness of dielectric/semiconductor interface was found to significantly impact the number of interfacial traps. The interfacial trap density values ( N t ) were calculated from the following equation where q is the electron charge, SS is the subthreshold slope, k is the Boltzmann's constant, and e is the base of the natural logarithm . The N t of dielectric/semiconductor interface was reduced from 1.9 × 10 12 to 0.3 × 10 12 cm −2 eV −1 with the infusion of IPN.…”

Dielectric Selection for Solution‐Processed High‐Mobility TIPS‐Pentacene Microwire Field‐Effect Transistors

“…These molecules are commonly used as the modification layer of dielectrics in OFETs, and high field‐effect mobility has been extensively shown based on these molecule‐modified dielectrics in previous reports . These dielectrics can effectively decrease the density of the carrier traps in the conducting channel and hence improve the carrier transport, resulting in high mobility. According to these facts, HMDS/SiO 2 , OTS/SiO 2 , and BCB/SiO 2 are selected as the target dielectrics for constructing high‐mobility TIPS‐pentacene single‐crystal microwire OFETs.…”