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The slowing-down of Moore’s law is shifting the computing paradigm towards solutions based on quantum and neuromorphic computing elements. Unlike conventional digital computing, neuromorphic computing is based on analog devices. In this work, we propose a three-terminal neuromorphic organic device (NODe) capable of providing both analog computing and memory in a single device by tuning its conductance. The availability of three-terminal devices enables the independent tuning of the NODes, preventing write sneak path issues typical of the two-terminal memristor crossbar array. The NODe conductance relaxes exponentially with a measured time constant of 2.9 h, furthermore, it can be operated at 51 MHz, corresponding to an estimated energy efficiency of 0.1 pJ per multiply-accumulate (MAC) operation. To demonstrate the NODe’s computing capabilities, a 3×3 crossbar array has been successfully used to perform edge detection and blurring on an image with 128×64 pixels.

The performance of organic photodetectors is steadily improving, and the specific detectivity, as a key figure of merit, has reached values of 1012–1013 Jones, i.e., comparable to that of silicon diodes but still considerably lower than the intrinsic limit. As with other semiconductor devices, the electrical performance of state-of-the art organic photodiodes (OPDs) is presently determined to a high degree by the presence of chemical impurities or structural defects which create carrier trapping states within the bandgap of organic active layer. This review aims to provide a comprehensive and timely account of trap-assisted charge generation and recombination in OPDs, with emphasis on the impact of these phenomena on photodetector performance parameters such as, noise and dark current density, responsivity, response speed, and ultimately, specific detectivity.

Organ-on-Chips (OoCs) have emerged as a human-specific experimental platform for preclinical research and therapeutics testing that will reduce the cost of pre-clinical drug development, provide better physiological relevance and replace animal testing. Yet, the lack of standardization and cost-effective fabrication technologies can hamper wide-spread adoption of OoCs. In this work we validate the use of flat panel display (FPD) technology as an enabling and cost-effective technology platform for biomedical applications by demonstrating facile integration of key OoC modules like microfluidics and micro electrode arrays (MEAs) in the standardized 96-well plate format. Individual and integrated modules were tested for their biological applicability in OoCs. For microelectrode arrays we demonstrate 90–95% confluency, 3 days after cell seeding and >70% of the initial mitochondrial cell activity for microfluidic devices. Thus highlighting the biocompatibility of these modules fabricated using FPD technology. Furthermore, we provide two examples of monolithically integrated microfluidics and microelectronics, i.e. integrated electronic valves and integrated MEAs, that showcase the strength of FPD technology applied to biomedical device fabrication. Finally, the merits and opportunities provided by FPD technology are discussed through examples of advanced structures and functionalities that are unique to this enabling platform.

Remote measurement of vital sign parameters like heartbeat and respiration rate represents a compelling challenge in monitoring an individual’s health in a noninvasive way. This could be achieved by large field-of-view, easy-to-integrate unobtrusive sensors, such as large-area thin-film photodiodes. At long distances, however, discriminating weak light signals from background disturbance demands superior near-infrared (NIR) sensitivity and optical noise tolerance. Here, we report an inherently narrowband solution–processed, thin-film photodiode with ultrahigh and controllable NIR responsivity based on a tandem-like perovskite-organic architecture. The device has low dark currents (<10 −6 mA cm −2), linear dynamic range >150 dB, and operational stability over time (>8 hours). With a narrowband quantum efficiency that can exceed 200% at 850 nm and intrinsic filtering of other wavelengths to limit optical noise, the device exhibits higher tolerance to background light than optically filtered silicon-based sensors. We demonstrate its potential in remote monitoring by measuring the heart rate and respiration rate from distances up to 130 cm in reflection.

Organic bulk heterojunction photodiodes (OPDs) attract attention for sensing and imaging. Their detectivity is typically limited by a substantial reverse bias dark current density (Jd). Recently, using thermal admittance or spectral photocurrent measurements, Jd has been attributed to thermal charge generation mediated by mid-gap states. Here, the temperature dependence of Jd in state-of-the-art OPDs is reported with Jd down to 10−9 mA cm−2 at −0.5 V bias. For a variety of donor-acceptor bulk-heterojunction blends it is found that the thermal activation energy of Jd is lower than the effective bandgap of the blends, by ca. 0.3 to 0.5 eV, but higher than expected for mid-gap states. Ultra-sensitive sub-bandgap photocurrent spectroscopy reveals that the minimum photon energy for optical charge generation in OPDs correlates with the dark current thermal activation energy. The dark current in OPDs is attributed to thermal charge generation at the donor-acceptor interface mediated by intra-gap states near the band edges.

Spatial atomic layer deposition (sALD) of p-type SnO is demonstrated using a novel liquid ALD precursor, tin(II)-bis(tert-amyloxide), Sn(TAA)2, and H2O as the coreactant in a process which shows an increased deposition rate when compared to conventional temporal ALD. Compared to previously reported temporal ALD chemistries for the deposition of SnO, deposition rates of up to 19.5 times higher are obtained using Sn(TAA)2 as a precursor in combination with atmospheric pressure sALD. Growths per cycle of 0.55 and 0.09 Å are measured at deposition temperatures of 100 and 210 °C, respectively. Common-gate thin film transistors (TFTs), fabricated using sALD with Sn(TAA)2 result in linear mobilities of up to 0.4 cm2 V–1 s–1 and on/off-current ratios, IOn/IOff > 102. The combination of enhanced precursor chemistry and improved deposition hardware enables unprecedently high deposition rate ALD of p-type SnO, representing a significant step toward high-throughput p-type TFT fabrication on large area and flexible substrates.

Low-dimensional perovskites attract increasing interest due to tunable optoelectronic properties and high stability. Here, it is shown that perovskite thin films with a vertical gradient in dimensionality result in graded electronic bandgap structures that are ideal for photodiode applications. Positioning low-dimensional, vertically-oriented perovskite phases at the interface with the electron blocking layer increases the activation energy for thermal charge generation and thereby effectively lowers the dark current density to a record-low value of 5 × 10−9 mA cm−2 without compromising responsivity, resulting in a noise-current-based specific detectivity exceeding 7 × 1012 Jones at 600 nm. These multidimensional perovskite photodiodes show promising air stability and a dynamic range over ten orders of magnitude, and thus represent a new generation of high-performance low-cost photodiodes.