Inkjet‐Printed Narrow‐Channel Mesoporous Oxide‐Based n‐Type TFTs and All‐Oxide CMOS Electronics

Abstract

Significant developments have also been noted in the printed/flexible electronics domain, where the performance of solution-processed thin film transistors (TFTs) may now easily be compared with their vacuum deposited (e.g. sputtered or pulsed-laser deposited) counterparts. [6] Notably, these solutionprocessed devices are of high interest for a wide range of portable electronic or Internet of Things (IoT) related devices. However, any digital electronic component essentially requires complementary metal oxide semiconductor (CMOS) technology to ensure high noise immunity and low power consumption. [7] Unfortunately, it is only the oxygen deficient n-type oxide semiconductors, the performance of which nearly matches that of polycrystalline silicon, whereas the performance of the p-type materials is substantially lower in comparison. In fact, the problem associated with the absence of matching/comparable p-type oxide semiconductors range beyond the CMOS electronics to other p-n junction devices, for example, solar cells. Here, the transport properties of p-type oxide semiconductors are primarily limited by their highly localized oxygen 2p orbitals in the valence band maximum (VBM), deep VBM, rigorous environmental and fabrication conditions and difficulties in high-quality film formation. [8][9][10][11] It should also be noted that the examples of solutionprocessed p-type oxide semiconductors are essentially limited to NiO, Cu x O, SnO, and delafossite-type CuMO 2 (M = Al and Cr). [8][9][10][11] Among these, Cu x O has been the most promising candidate owing to its high theoretical Hall mobility, non-toxicity, suitable optical properties, and low cost. [12,13] Although it has been a well-known semiconductor even in the pre-silicon era, resurgent interest in Cu 2 O has been spurred when Matsuzaki et al. demonstrated a Hall mobility of 90 cm 2 V −1 s −1 for epitaxial Cu 2 O films on MgO in 2008. [14] The subsequent studies have reported about p-type Cu x O deposition via sputtering, [14] pulsed laser deposition [15,16] and thermal oxidation techniques. [17] Solution-based fabrication techniques involving either spin/spray coating or inkjet printing have also been reported. [15,[18][19][20][21][22][23] However, when it comes to Cu x O-based TFTs, the typical process temperatures (≥400 °C) or reported operating voltages have always been very high. [24][25][26] Oxide semiconductors are becoming the materials of choice for modern-day display industries. The performance of solution-processed oxide thin film transistors (TFTs) has also improved dramatically over the last few years. However, while oxygen deficient n-type semiconductors can demonstrate excellent electronic transport, the performance of p-type materials has remained unsatisfactory. Consequently, only the n-type semiconductor-based pseudo-complementary metal oxide semiconductor (CMOS) technology has attracted tremendous interests recently; yet, the high power dissipation remains a problem. Here, this work demonstrates all-oxide CMOS invertors with high-performa...

Inkjet-Printed, High-Performance MoS2 Transistors and Unipolar Logic Electronics

“…Subsequently, the CSPE is printed as the electrolytic insulator. The electrolyte gating of the devices allows a conformal interface with the semiconductor and a high electrolytic double-layer capacitance of the order of 10 μF·cm –2 , which allows device operation at less than 3 V. ,,− …”

Inkjet-Printed Transparent Asymmetric Microsupercapacitors with Mesoporous NiCo2O4 and Mn2O3 Electrodes

“…In this regard, in the present study, we have fabricated composition and methodology-tailored NiCo 2 O 4 electrodes with a cocontinuous, mesoporous architecture using inkjet printing and following a soft templating technique with Pluronic F127 as the structure-directing agent. Here, it may be noted that the earlier reports on cocontinuous mesoporous structure-based oxide materials have demonstrated a very high surface-to-volume ratio and essentially zero dead weight; therefore, with such nanostructures, high specific capacity can be expected. ,− Indeed, the printed mesoporous NiCo 2 O 4 electrodes have shown a record high gravimetric specific capacitance of 4122 F g –1 (1649 C g –1 ) at a specific current of 1 A g –1 . Next, inkjet-printed asymmetric supercapacitors have also been fabricated using a single-step printing and annealing (at 500 °C) protocol, where the mesoporous NiCo 2 O 4 cathodes have been printed against the mesoporous Mn 2 O 3 anodes on a planar prepatterned substrate.…”

α‐TeO2 Oxide as Transparent p‐Type Semiconductor for Low Temperature Processed Thin Film Transistor Devices

“…Decades of research work have been devoted in oxide semiconducting materials for the realization of next-generation transparent/flexible electronic devices in a wide range of application areas including wearable/implantable, healthcare, high end displays and smart textiles. [1][2][3][4][5][6] Notably, their remarkable electronic properties, superior thermal/environmental stability, high transparency, and low processing cost have enabled them to realize in potential commercialization of high speed/highdefinition displays and energy efficient transparent electronic devices. As an outcome of these efforts oxygen deficient n-type oxide semiconductors have shown nearly equivalent transistor performance with polycrystalline silicon.…”