The Hidden Potential of Polysilsesquioxane for High‐k: Analysis of the Origin of its Dielectric Nature and Practical Low‐Voltage‐Operating Applications beyond the Unit Device

Abstract

Low-voltage-operating high-performance organic field-effect transistors (OFETs) are regarded as the building blocks of analog and digital integrated circuits for next-generation electronics. To fulfill this, such an OFET must have high-dielectric constant (k) characteristics for increasing the capacitance values to make enough of a field-effect charge, a hydrophobic surface that does not cause charge trapping, and a low leakage current property to guarantee operating stability. This study demonstrates a new strategy to induce high-k characteristics (>8) with durable polysilsesquioxane (PSQ)-based dielectrics. This strategy involves realizing a dipolar side-chain reorientation under an electric field and its applications to low-voltage-driving OFETs showing high field-effect mobility levels as high as 27 cm 2 V -1 s -1 . Different PSQs are characterized, and the differences in their characteristics lead to distinct polarization phenomena, resulting in different hysteresis behaviors during device operation. The printed unit devices can also be fabricated on flexible platforms and integrated devices through these materials and show robust switching or memory performances under low-voltage-operation conditions. Therefore, this facile but powerful synthesis strategy for high-k PSQ dielectrics can pave a new path for the production of practical printable high-k dielectrics for organic electronics and hence realize next-generation integrated electronics.

Molecular and Atomic Layer Deposition of Hybrid Polyimide–Al2O3 Gate Dielectrics for Flexible Electronic Devices

“…A promising strategy to tackle this issue is to develop hybrid organic–inorganic materials, which can combine the desired attributes from both organic and inorganic dielectrics. Following this line, a number of hybrid gate dielectric materials have been reported, such as hybrid polyvinyl alcohol/SiO 2 , self-assembled polymer–ZrO x multilayer, polysilsesquioxane materials, and AlO x - or ZrO x -grafted poly­(2-hydroxyethyl methacrylate). , However, all these hybrid dielectrics were made by solution-based processes − or CVD, , which could be of serious concern for industrial scaling up, where the thin dielectric layers should be reliably made with large-scale uniformity and pinhole-free. Therefore, there is a great need to develop highly reliable and scalable methods to fabricate the hybrid dielectric materials.…”

Electrohydrodynamic-Jet-Printed Phthalimide-Derived Conjugated Polymers for Organic Field-Effect Transistors and Logic Gates

“…With these NOT gates, integrated logic gates (NAND and NOR gates) were fabricated by linking an additional drive transistor in parallel and in series, respectively. 33 NAND (Figure 6a middle) and NOR (Figure 6a bottom) logic gates were produced by the EHD jet printing of the PBDTTTffPI semiconductors. Figure 6c shows the V out values of the NAND and NOR gates according to input sets of signals (combinations of V A and V B ).…”

Azide-functionalized Ligand Enabling Organic–Inorganic Hybrid Dielectric for High-Performance Solution-Processed Oxide Transistors

“…1 H NMR, 13 C NMR, and 19 F NMR spectra were recorded on a Bruker Avance-400 spectrometer using TMS as internal standard. Chemical shifts are reported in parts per million (ppm).…”

“…Notably, most of the high electron mobility (> 30 cm 2 V − 1 s − 1 ) oxide TFTs were based on high-k inorganic gate dielectrics. Compared with conventional SiO 2 (k = 4), high-k oxides such as HfO 2 , ZrO 2 , Ta 2 O 5 , and Al 2 O 3 are ideal candidates for realizing a high-capacitance dielectric layer capable of low-voltage driving and high density of charge accumulation [10][11][12][13][14] . However, these high-k inorganic dielectric layers are hindered by 1) expensive deposition equipment and high process temperature for vacuum deposition, and 2) imperfect inorganic purity and porous morphology for solution deposition 15 .…”