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In this paper, the influence of oxygen partial pressure (${P}_{\textsf {O2}}$) during physical vapor deposition on the field-effect mobility of amorphous InGaZnO (IGZO) thin-film transistor (TFT) is investigated in a wide range of ${P}_{\textsf {O2}}$. The field-effect mobility reduced from 12 to 0.1 cm $^{\textsf {2}}/\textsf {V}~\cdot $ s when the ${P}_{\textsf {O2}}$ is increased from 0.3 to 1.5 mTorr. Temperature-dependent TFT measurements suggest that carrier transport in the TFTs deposited at the ${P}_{\textsf {O2}}$ of 0.3 mTorr can be described according to the multiple trap and release/percolation model. However, the carrier transport in the TFTs deposited at the ${P}_{\textsf {O2}}$ of 1.5 mTorr conforms to Mott’s variable-range hopping model. The elastic recoil detection analysis indicates that hydrogen concentration in the IGZO film increased with ${P}_{\textsf {O2}}$. The X-ray photoelectron spectroscopy results indicate that In vacancy (${V}_{\textsf {In}}$) defects formed in the IGZO film deposited at high ${P}_{\textsf {O2}}$. Scattering induced by hydrogen and pinning of Fermi level below the conduction band edge by ${V}_{\textsf {In}}$ are plausible reasons for the low field-effect mobility in TFTs deposited at high ${P}_{\textsf {O2}}$. [ABSTRACT FROM AUTHOR]

Abstract: We present a thin‐film dual‐layer bottom barrier on polyimide that is compatible with 350°C backplane processing for organic light‐emitting diode displays and that can facilitate foldable active‐matrix organic light‐emitting diode devices with a bending radius of <2 mm. We demonstrate organic light‐emitting diodes that survive bending over 0.5 mm radius for 10.000× based on the high‐temperature bottom barrier. Furthermore, we show compatibility of the bottom barrier with the backplane process by fabricating active‐matrix organic light‐emitting diode displays on GEN1‐sized substrates. [ABSTRACT FROM AUTHOR]

Abstract: High‐resolution RGB organic light‐emitting diode frontplane is a key enabler for direct‐view transparent augmented reality displays. In this paper, we demonstrate 1250 ppi passive displays and semi‐transparent active displays. Organic light‐emitting diode photolithography can provide pixel density above 1000 ppi while keeping effective emission area high because of high aperture ratio. Patterns with 2 μm line pitch were successfully transferred to emission layers, indicating possible further pixel density scaling. Lifetime after patterning, key parameter enabling industrialization, is above 150 h (T90 at 1000 nit). [ABSTRACT FROM AUTHOR]

We report on the fabrication of organic photodetectors (OPD) based on isolated islands of P3HT:PCBM. Pattern transfer to the active material was done with photolithography based on non-fluorinated solvents and the excessive organic semiconductor was removed with oxygen plasma reactive ion etching. The photoresist system used was found to be benign to the P3HT:PCBM layer as confirmed by absorption, thickness and roughness measurements. Current–voltage characteristics and external quantum efficiency (EQE) remained unchanged after the patterning process. It was demonstrated that it is possible to photolithographically pattern isolated islands with 200 μm edge length with the same dark current density (<10 −5 A/cm 2 at −2 V bias voltage) and photocurrent density (>5 × 10 −3 A/cm 2 at −2 V). Furthermore, concerning the solar cell performance, the patterned, small-area devices showed power conversion efficiency of 2.1% and fill-factor of 60%. Dark current was observed to depend on the size of the remaining semiconductor island, which was demonstrated on OPDs with diameter of 50 μm. The presented results show the feasibility of fabrication of isolated devices based on organic semiconductors patterned with non-fluorinated photolithography. [ABSTRACT FROM AUTHOR]

Highlights: [•] Low area consumption per complementary logic gate (0.08mm2). [•] Organic complementary inverter with static power of 10nW at V dd =5V and stage delay of 2μs at V dd =10V. [•] Organic complementary 8bit transponder chip with die size of 30mm2 and data rate of 2.7kbits/s. [Copyright &y& Elsevier]

Abstract: In this work, a completely scalable integration process is presented for organic–inorganic complementary logic, based on low-temperature spin-coated n-type metal oxide TFTs and thermally evaporated p-type pentacene TFTs. Both transistor types are photolithographically processed side-by-side, without the use of any shadow mask. High performance n-type metal oxide TFTs, post-annealed at a maximum temperature of only 250°C, exhibit saturation mobilities exceeding 2cm2/(Vs), subthreshold swing as low as 0.19V/decade and I on/I off ratios beyond 107 after integration with p-type pentacene TFTs. Using this hybrid complementary technology, 5-stage and 19-stage ring-oscillators are demonstrated, operating at supply voltages as low as 2.5V. The ring-oscillators oscillate at a frequency of more than 110kHz, corresponding to stage delays as low as 0.74μs, at a supply bias of 20V. [Copyright &y& Elsevier]

Electrode grids are used in neuroscience research and clinical practice to record electrical activity from the surface of the brain. However, existing passive electrocorticography (ECoG) technologies are unable to offer both high spatial resolution and wide cortical coverage, while ensuring a compact acquisition system. The electrode count and density are restricted by the fact that each electrode must be individually wired. This work presents an active micro-electrocorticography (µECoG) implant that tackles this limitation by incorporating metal oxide thin-film transistors (TFTs) into a flexible electrode array, allowing to address multiple electrodes through a single shared readout line. By combining the array with an incremental-ΔΣ readout integrated circuit (ROIC), the system is capable of recording from up to 256 electrodes virtually simultaneously, thanks to the implemented 16:1 time-division multiplexing scheme, offering lower noise levels than existing active µECoG arrays. In vivo validation is demonstrated acutely in mice by recording spontaneous activity and somatosensory evoked potentials over a cortical surface of ≈8×8 mm 2 . The proposed neural interface overcomes the wiring bottleneck limiting ECoG arrays, holding promise as a powerful tool for improved mapping of the cerebral cortex and as an enabling technology for future brain-machine interfaces., (© 2023 The Authors. Advanced Science published by Wiley-VCH GmbH.)