Sn-doped indium oxide (ITO) semiconductor nano-films are fabricated by plasma-enhanced atomic layer deposition using trimethylindium (TMIn), tetrakis(dimethylamino)tin (TDMASn), and Oplasma as the sources of In, Sn and O, respectively. A shared temperature window of 150 °C- 200 °C is observed for the deposition of ITO nano-films. The introduction of Sn into indium oxide is found to increase the concentration of oxygen into the ITO films and inhibit crystallization.
View Article and Find Full Text PDFTo enhance the electrical safe operation area (eSOA) of laterally diffused metal oxide semiconductor (LDMOS) transistors, a novel reduced surface electric field (Resurf) structure in the n-drift region is proposed, which was fabricated by ion implantation at the surface of the LDMOS drift region and by drift region dimension optimization. Technology computer-aided design (TCAD) simulations show that the optimal value of Resurf ion implantation dose 1 × 10 cm can reduce the surface electric field in the n-drift region effectively, thereby improving the ON-state breakdown voltage of the device (BV). In addition, the extended n-drift region length of the L design also improves device BV significantly, and is aimed at reducing the current density and the electric field, and eventually suppressing the n-drift region impact ionization.
View Article and Find Full Text PDFFilter-free wavelength-selective photodetectors have garnered significant attention due to the growing demand for smart sensors, artificial intelligence, the Internet of Everything, and so forth. However, the challenges associated with large-scale preparation and compatibility with complementary metal-oxide-semiconductor (CMOS) technology limit their wide-ranging applications. In this work, we address the challenges by constructing vertically stacked graded-band-gap zinc-tin oxide (ZTO) thin-film transistors (TFTs) specifically designed for wavelength-selective photodetection.
View Article and Find Full Text PDFMicromachines (Basel)
December 2023
Flip chip bonding technology on gold-tin (Au-Sn) microbumps for MEMS (Micro Electro Mechanical Systems) and 3D packaging is becoming increasingly important in the electronics industry. The main advantages of Au-Sn microbumps are a low electrical resistance, high electrical reliability, and fine pitch. However, the bonding temperature is relatively high, and the forming mechanism of an intermetallic compound (IMC) is complicated.
View Article and Find Full Text PDFHarmonic distortion is one of the dominant factors limiting the overall signal-to-noise and distortion ratio of seismic-grade sigma-delta MEMS accelerometers. This study investigates harmonic distortion based on the multiple degree-of-freedom model (MDM) established in our previous study. The main advantage of using an MDM is that the effect of finger flexibility on harmonic distortion is considered.
View Article and Find Full Text PDFThe high-order mechanical resonances of the sensing element in a high-vacuum environment can significantly degrade the noise and distortion performance of seismic-grade sigma-delta MEMS capacitive accelerometers. However, the current modeling approach is unable to evaluate the effects of high-order mechanical resonances. This study proposes a novel multiple-degree-of-freedom (MDOF) model to evaluate the noise and distortion induced by high-order mechanical resonances.
View Article and Find Full Text PDFACS Appl Mater Interfaces
February 2023
Ferroelectric field effect transistor (FeFET) memories with hafnium zirconium oxide (HZO) ferroelectric gate dielectric and ultrathin InOchannel exhibit promising applicability in monolithic three-dimensional (M3D) integrated chips. However, the inferior stability of the devices severely limits their applications. In this work, we studied the effect of single cycle of atomic-layer-deposited Al-O bonds repeatedly embedded into an ultrathin InOchannel (∼2.
View Article and Find Full Text PDFThanks to their excellent compatibility with the complementary metal-oxide-semiconductor (CMOS) process, antiferroelectric (AFE) HfO/ZrO-based thin films have emerged as potential candidates for high-performance on-chip energy storage capacitors of miniaturized energy-autonomous systems. However, increasing the energy storage density (ESD) of capacitors has been a great challenge. In this work, we propose the fabrication of ferroelectric (FE) HfZrO/AFE HfZrO bilayer nanofilms by plasma-enhanced atomic layer deposition for high ESD capacitors with TiN electrodes.
View Article and Find Full Text PDFACS Appl Mater Interfaces
September 2022
The high surface-to-volume ratio and decent material properties of two-dimensional (2D) transition metal dichalcogenides (TMDs) make them advantageous as an active channel in field-effect transistor (FET)-type gas sensing devices. However, most existing TMD gas sensors are based on a two-terminal resistance-type structure and suffer from low responsivity and slow response, which has urged materials optimization as well as device engineering. Metal-organic frameworks (MOFs) have a large number of ordered binding sites in the pores that can specifically bind to gas molecules and can be decorated on TMD surfaces to enhance gas sensing capabilities.
View Article and Find Full Text PDFSpectrum reconstruction with filter-free microspectrometers has attracted much attention owing to their promising potential in analysis systems, on-chip spectroscopy characterizations, hyperspectral imaging, . Further efforts in this field can be devoted to improving the performance of microspectrometers by employing high-performance photosensitive materials and optimizing the reconstruction algorithms. In this work, we demonstrate spectrum reconstruction with a set of photodetectors based on graded-band-gap perovskite quantum dot (PQD) heterojunctions using both calculation and machine learning algorithms.
View Article and Find Full Text PDFACS Appl Mater Interfaces
February 2022
Function convergence of gas sensing and neuromorphic computing is attracting much research attention due to the promising potential in electronic olfactory, artificial intelligence, and internet of everything systems. However, the current neuromorphic gas-sensing systems are either realized via integration of gas detectors and neuromorphic devices or operating with three-terminal synaptic transistors at high voltages, leading to a rather high system complexity or power consumption. Herein, gas-modulated synaptic diodes with lateral structures are developed to converge sensing, processing, and storage functions into a single device.
View Article and Find Full Text PDFElectronic-Photonic integrated systems have attracted intensive attention in addressing the explosively increasing data-processing issue in the post-Moore era. However, the tremendous size difference between basic electronic and photonic units poses challenges for the further deep convergence of optoelectronic microprocessors. Here, we report a floating-gate transistor fabricated with complementary metal-oxide-semiconductor compatible technologies, which can realize multilevel photoelectric logic computing and memory simultaneously.
View Article and Find Full Text PDFThe data processing efficiency of traditional computers is suffering from the intrinsic limitation of physically separated processing and memory units. Logic-in-memory and brain-inspired neuromorphic computing are promising in-memory computing paradigms for improving the computing efficiency and avoiding high power consumption caused by extra data movement. However, memristors that can conduct digital memcomputing and neuromorphic computing simultaneously are limited by the difference in the information form between digital data and analogue data.
View Article and Find Full Text PDFBMC Bioinformatics
September 2021
Background: Brain tumor segmentation is a challenging problem in medical image processing and analysis. It is a very time-consuming and error-prone task. In order to reduce the burden on physicians and improve the segmentation accuracy, the computer-aided detection (CAD) systems need to be developed.
View Article and Find Full Text PDFHalide perovskites are promising photoactive materials for filter-free color-imaging sensors owing to their outstanding optoelectronic properties, tunable bandgaps, and suitability for large-scale fabrication. However, producing patterned perovskite films of sufficiently high quality for such applications poses a challenge for existing fabrication methods: using solution processes to prepare patterned perovskite films is complicated, while evaporation methods often result in perovskite photodetectors with limited performance. In this paper, the authors report the development of an improved evaporation method in which substrates are treated with a brominated (3-aminopropyl) triethoxysilane self-assembled monolayer to improve the properties of the patterned perovskite films.
View Article and Find Full Text PDFThe electronic-photonic convergent systems can overcome the data transmission bottleneck for microchips by enabling processor and memory chips with high-bandwidth optical input/output. However, current silicon-based electronic-photonic systems require various functional devices/components to convert high-bandwidth optical signals into electrical ones, thus making further integrations of sophisticated systems rather difficult. Here, we demonstrate thin-film transistor-based photoelectric memories employing CsPbBr/CsPbI blend perovskite quantum dots (PQDs) as a floating gate, and multilevel memory cells are achieved under programming and erasing modes, respectively, by imputing high-bandwidth optical signals.
View Article and Find Full Text PDFOptoelectronic devices for light or spectral signal detection are desired for use in a wide range of applications, including sensing, imaging, optical communications, and in situ characterization. However, existing photodetectors indicate only light intensities, whereas multiphotosensor spectrometers require at least a chip-level assembly and can generate redundant signals for applications that do not need detailed spectral information. Inspired by human visual and psychological light perceptions, the compression of spectral information into representative intensities and colours may simplify spectrum processing at the device level.
View Article and Find Full Text PDFAlthough the energy consumption of reported neuromorphic computing devices inspired by biological systems has become lower than traditional memory, it still remains greater than bio-synapses (≈10 fJ per spike). Herein, a flexible MoS-based heterosynapse is designed with two modulation modes, an electronic mode and a photoexcited mode. A one-step mechanical exfoliation method on flexible substrate and low-temperature atomic layer deposition process compatible with flexible electronics are developed for fabricating wearable heterosynapses.
View Article and Find Full Text PDFAs one of the emerging neuromorphic computing devices, memristors may break through the limitation of traditional computers with a von Neumann architecture. However, the development of flexible memristors is limited by the high-temperature fabrication process, large operating voltage and non-uniform distribution of resistance. The room-temperature process has attracted great attention due to its advantages of low thermal dissipation, low cost and excellent compatibility with flexible electronics.
View Article and Find Full Text PDFTo construct an artificial intelligence system with high efficient information integration and computing capability like the human brain, it is necessary to realize the biological neurotransmission and information processing in artificial neural network (ANN), rather than a single electronic synapse as most reports. Because the power consumption of single synaptic event is ∼10 fJ in biology, designing an intelligent memristors-based 3D ANN with energy consumption lower than femtojoule-level (e.g.
View Article and Find Full Text PDFThin-film transistors (TFTs) based on amorphous In-Ga-Zn-O (a-IGZO) channels present high mobility, large-area uniformity, mechanical flexibility and photosensitivity, and thus have extensive applicability in photodetectors, wearable devices, However, pure a-IGZO based photosensors only exhibit a UV light response with limited sensitivity performance. By utilizing interfacial hydrogen doping, it is demonstrated that the a-IGZO TFTs with the AlO dielectric deposited by plasma-enhanced atomic layer deposition at room temperature (RT) have excellent photosensing performance, such as a photoresponsivity of over 6 × 10 A W and a light to dark current ratio up to 10. This is attributed to spontaneous interfacial hydrogen doping into the a-IGZO channel during sputtering deposition of a-IGZO on hydrogen-rich AlO films, thus generating subgap states in the band gap of IGZO.
View Article and Find Full Text PDFAmorphous In-Ga-Zn-O (a-IGZO) thin-film transistor (TFT) memories are attracting many interests for future system-on-panel applications; however, they usually exhibit a poor erasing efficiency. In this article, we investigate voltage-polarity-dependent programming behaviors of an a-IGZO TFT memory with an atomic-layer-deposited ZnO charge trapping layer (CTL). The pristine devices demonstrate electrically programmable characteristics not only under positive gate biases but also under negative gate biases.
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