David Wei Zhang

David Wei Zhang
Fudan University · School of Microelectronics

About

489
Publications
93,455
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
9,124
Citations
Citations since 2017
297 Research Items
7748 Citations
201720182019202020212022202305001,0001,5002,000
201720182019202020212022202305001,0001,5002,000
201720182019202020212022202305001,0001,5002,000
201720182019202020212022202305001,0001,5002,000

Publications

Publications (489)
Article
Full-text available
High-entropy oxides (HEOs), which incorporate multiple-principal cations into single-phase crystals and interact with diverse metal ions, extend the border for available compositions and unprecedented properties. Herein, w e report on a high-entropy-stabilized (Ca0.2 Sr0.2 Ba0.2 La0.2 Pb0.2 )TiO3 perovskite, and the effective absorption bandwidth (...
Article
Full-text available
The effect of the source/drain compressive stress on the mechanical stability of stacked Si nanosheets (NS) during the process of channel release has been investigated. The stress of the nanosheets in the stacking direction increased first and then decreased during the process of channel release by technology computer-aided design (TCAD) simulation...
Article
With the development of bioelectronics, brain-inspired artificial synapses become more and more important. To simulate artificial synapse, a HfAlO ferroelectric tunnel junction (FTJ) was fabricated, which can simulate short-term synaptic plasticity for neuromorphic computing. The devices realize the synaptic function with low power consumption of a...
Article
Artificial neural networks (ANNs) have strong learning and computing capabilities, and alleviate the problem of high power consumption of traditional von Neumann architectures, providing a solid basis for advanced image recognition, information processing, and low-power detection. Recently, a two-dimensional (2D) MoS2 field-effect transistor (FET)...
Article
Full-text available
Neuromorphic computing memristors are attractive to construct low-power- consumption electronic textiles due to the intrinsic interwoven architecture and promising applications in wearable electronics. Developing reconfigurable fiber-based memristors is an efficient method to realize electronic textiles that capable of neuromorphic computing functi...
Article
Linear weights modulation in neuromorphic memristor plays an important role in high-accuracy image recognition task. Herein, a Li <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">+</sup> doped organic artificial memristor for neuromorphic computing was proposed for linear weights update, which shows act...
Article
In this work, time-dependent threshold voltage ( $\textit{V}_{\text{TH}}$ ) instability of p-GaN gate high electron mobility transistors (HEMTs) under OFF-state drain stress is systematically investigated. An anomalous $\textit{V}_{\text{TH}}$ shift behavior is observed with an initial negative shift followed by a kink and a positive shift upon...
Article
The unipolar photocurrent in conventional photodiodes (PDs) based on photovoltaic effect limits the output modes and potential versatility of these devices in photodetection. Bipolar photodiodes with photocurrent switching are emerging as a promising solution for obtaining photoelectric devices with unique and attractive functions, such as optical...
Article
Adaptation is essential for the life activities of organisms. Simulating biological visual adaptation behavior is still a serious challenge in the development of artificial visual perception systems. Here, an organic artificial optoelectronic neuromorphic device is presented, which has a memory window greater than 20V, multi-level storage character...
Article
Solar-blind photodetectors (SBPDs) have attracted great interests for the potential applications such as missile guidance, biological detection, and ultra-violet imaging. Although a large number of Ga2O3-SBPDs have been reported, most of them with thick light absorption layers still cannot effectively alleviate the trade-off between high responsivi...
Article
Full-text available
With the rapid development of the Internet of Things, there is a great demand for portable gas sensors. Metal oxide semiconductors (MOS) are one of the most traditional and well-studied gas sensing materials and have been widely used to prepare various commercial gas sensors. However, it is limited by high operating temperature. The current researc...
Article
Neuromorphic computing has attracted broad attention in recent years, owing to its break in the bottleneck of traditional von Neumann architecture with its advantages of high efficiency and low power consumption. However, many reported works only focused on the improvement of the performance of a single device, or assumed that each neuron in the ar...
Article
Traditional von Neumann architecture is facing severe challenges due to separated physical structure of memory and processing units, which inspires the development of in‐memory computing electronics. Intriguingly, as a kind of complementary metal‐oxide‐semiconducor compatible ferroelectric material, HfO2 is widely studied based on first‐principles...
Article
In this Letter, trapping effects of a Schottky lightly Mg-doped p-GaN gate stack for low-power applications have been investigated, and further analysis focusing on AlGaN/GaN interface traps under γ-ray irradiation has been carried out. A negligible shift in the flatband voltage with γ-ray irradiation dose up to 800 krad indicates the superior radi...
Article
The thermal–mechanical and signal reliability of through-silicon via (TSV) occupies an important position in three-dimensional integrated circuits (3D-ICs). However, few studies combined the thermal–mechanical and signal reliability are found. In the work, a new differentiated structure of TSV is proposed to decrease the peak thermal stress without...
Article
In this work, a stepped split trench-gate (SSG) insulated-gate bipolar transistor (IGBT) employing enhanced carrier storage (CS) technique is proposed. The trench gate is split into two symmetrical gates in a deep trench structure (connected to the emitter). The bottom of the deep trench is embedded into the drift region to reduce the Miller capaci...
Article
Full-text available
Thanks to their excellent compatibility with the complementary metal-oxide-semiconductor (CMOS) process, antiferroelectric (AFE) HfO2/ZrO2-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 cap...
Article
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 respon...
Article
The unique features of ambipolar two-dimensional materials open up a great opportunity to build gate-programmable devices for reconfigurable circuit applications, e.g., PN junctions for rectifier circuits. However, current-reported rectifier circuits usually consist of one gate-programmable PN junction as the rectifier and one resistor as the load,...
Article
The rapid development of machine vision applications demands hardware that can sense and process visual information in a single monolithic unit to avoid redundant data transfer. Here, we design and demonstrate a monolithic vision enhancement chip with light-sensing, memory, digital-to-analog conversion, and processing functions by implementing a 61...
Article
Full-text available
With the development of artificial intelligence and the Internet of Things, the number of sensory nodes is growing rapidly, leading to the exchange of large quantities of redundant data between sensors and computing units. In-sensor computing schemes with integration of sensing and processing have provided a promising route to address the sensing/p...
Article
Full-text available
Two-dimensional (2D) transition-metal dichalcogenides have promising optoelectronic applications. However, most reported MoS2-based photodetectors are based on MoS2 flakes, dozens of microns in size, prepared by mechanical exfoliation or chemical vapor deposition, which limits their practical applications. In this study, a wafer-scale, continuous,...
Article
Full-text available
A new S/D trimming process was proposed to significantly reduce the parasitic RC of gate-all-around (GAA) nanosheet transistors (NS-FETs) while retaining the channel stress from epitaxy S/D stressors at most. With optimized S/D trimming, the 7-stage ring oscillator (RO) gained up to 27.8% improvement of delay with the same power consumption, for a...
Article
In 2 O 3-based metal-oxide-semiconductor channel materials are attractive for thin-film transistors and novel back-end-of-line (BEOL) compatible devices and have attracted intensive research activities in recent years. However, several challenges remain, such as the ultrahigh electron density and the nature of polycrystalline films. To overcome the...
Article
Two-dimensional (2D) semiconductors can be utilized to continually miniaturize nanoscale electronic devices. However, achieving a practical solution for satisfying electrical contact with 2D semiconductors remains challenging. In this study, we developed a novel contact structure with transferred multilayer (t-ML) MoS2 by integrating both edge and...
Article
Deep ultraviolet (DUV) phototransistors are key integral of optoelectronics bearing a wide spectrum of applications in flame sensor, military detector, oil spill detection, biological sensor, and artificial intelligence fields. In order to further improve the responsivity of UV photodetectors based on β-Ga2O3, in present work, high-performance β-Ga...
Article
Organic materials with good biocompatibility and mechanical flexibility have great application potential in photonic neuromorphic computing. Here, the organic optoelectronic synapse for neuromorphic computing is fabricated on a flexible substrate. The excellent ferroelectricity of poly(vinylidene fluoride-trifluoroethylene) P(VDF-TrFE) endows the d...
Article
In order to imitate brain-inspired biological information processing systems, various neuromorphic computing devices have been proposed, most of which were prepared on rigid substrates and have energy consumption levels several orders of magnitude higher than those of biological synapses (∼10 fJ per spike). Herein, a new type of wearable organic fe...
Article
In this letter, a dual Al <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> /Hf <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.5</sub> Zr <sub...
Article
Full-text available
Deep-ultraviolet (DUV) phototransistors have shown great potential applications in UV imaging, artificial intelligence, and wearable optoelectronics. Among a large number of wide bandgap semiconductors, the quasi-two-dimensional β-Ga2O3 is considered as an ideal candidate for DUV photodetector applications. Herein, we report a high responsivity (R)...
Article
A new circuit architecture to drive GaN e-HEMT power device was proposed in this work, which was taped out on TSMC 0.18um BCD process and successfully tested. With the proposed driver circuit, gate voltage overshoot as well as ringing on GaN e-HEMT device has been successfully suppressed, while not sacrificing GaN e-HEMT advantage of high switching...
Preprint
Full-text available
The early transition metals Ruthenium (Ru) and Cobalt (Co) are of high interest as alternative materials for replacing Cu in next generation interconnects. Plasma-enhanced atomic layer deposition (PE-ALD) is used to deposit metal thin films in high-aspect ratio structures of vias and trenches in nanoelectronic devices. At the initial stages, the su...
Article
Recent advances in van der Waals (vdW) heterostructures have extensively promoted the development of new-generation electronic devices. However, the normally utilized mechanical exfoliation method for preparing two-dimensional (2D) semiconductors is not scalable for circuit-level application. Herein, the fabrication and characterization of wafer-sc...
Article
Flash memory with high operation speed and stable retention performance is in great demand to meet the requirements of big data. In addition, the realisation of ultrafast flash memory with novel functions offers a means of combining heterogeneous components into a homogeneous device without considering impedance matching. This report proposes a 20...
Article
Full-text available
The effect of a macromolecular additive on the etching rate of aluminum (Al) horizontal etching in the wet process was investigated in this work. The horizontal etching in the Al wet etching process became more evident as the film Al becomes thicker. The proposed macromolecule additive, including polyethylene-polypropylene glycol, was added into th...
Article
Amorphous In-Ga-Zn-O (a-IGZO) thin-film transistor (TFT) memories with novel p-SnO/n-SnO 2 heterojunction charge trapping stacks (CTSs) are investigated comparatively under a maximum fabrication temperature of 280 ℃. Compared to a single p-SnO or n-SnO 2 charge trapping layer (CTL), the heterojunction CTSs can achieve electrically programmable and...
Article
Full-text available
A systematic study of the selective etching of p-GaN over AlGaN was carried out using a BCl3/SF6 inductively coupled plasma (ICP) process. Compared to similar chemistry, a record high etch selectivity of 41:1 with a p-GaN etch rate of 3.4 nm/min was realized by optimizing the SF6 concentration, chamber pressure, ICP and bias power. The surface morp...
Article
Full-text available
Wearable touch panel, a typical flexible electronic device, can recognize and feedback the information of finger touch and movement. Excellent wearable touch panels are required to accurately and quickly monitor the signals of finger movement as well as the capacity of bearing various deformation. High-performance thermistor materials are one of th...
Article
Systemic sclerosis (SSc) is a multi-organ desmosis exhibiting the symptom of skin sclerosis. Due to the complexity of human skin, the assessment of skin sclerosis was traditionally implemented through palpation by a clinician, which has numerous limitations. Wearable flexible sensor is expected to open up new approaches for SSc diagnosis. Herein, a...
Article
Two‐dimentional semiconductors have shown potential applications in multi‐bridge channel field‐effect transistors (MBC‐FETs) and complementary field‐effect transistors (C‐FETs) due to their atomic thickness, stackability, and excellent electrical properties. However, the exploration of MBC‐FET and C‐FET based on large‐scale 2D semiconductors is sti...
Article
Large‐volume data storage and high‐efficiency data processing have been greatly urged by the fast development in artificial intelligence and internet‐of‐things involving novel semiconductor materials. Logic‐in‐memory has provided a promising route to address the processing/storage bottleneck in advanced computing systems. Here, we demonstrate a log...
Article
Full-text available
Cobalt (Co) is a potential candidate in replacing copper for interconnects and has been applied in the trenches in semiconductor industry over twenty years. A non-oxidizing reactant is required in...
Article
It has become more challenging to suppress the negative bias temperature instability (NBTI) in advanced FinFET technology which is largely originated from the dielectric/channel interface in HKMG structure. In this work, we report the experimental approach to mitigate the NBTI in 14-nm FinFET devices through HKMG thermal processing optimization. Th...
Article
The length of diffusion (LOD) effect in low- ${V}_{\text{t}}$ (LVT) and standard- ${V}_{\text{t}}$ (SVT) logic is investigated and the yield and dynamic power consumption (DPC) have been optimized by using back-end of line (BEOL) design-technology cooptimization (DTCO). The resistor–capacitor ( $RC$ ) characteristics of the Via in the back-end s...
Article
The complementary field-effect transistor (CFET) with stacked N-type FET (NFET) and P-type FET (PFET) is an attractive approach to shrink the footprint of multiple devices at circuit level and increase transistor density. Compared with traditional device structure, the unique geometry of CFET brings very different parasitics. In this work, we take...
Article
Research of artificial synapses is increasing in popularity with the development of bioelectronics and the appearance of wearable devices. Because the high-temperature treatment process of inorganic materials is not compatible with flexible substrates, organic ferroelectric materials that are easier to process have emerged as alternatives. An organ...
Article
Full-text available
In this work, wafer-scale continuous and uniform MoS2/(HfO2)x(Al2O3)1−x (HfAlO) heterojunctions were prepared by atomic layer deposition (ALD). The energy band alignment of MoS2/HfAlO heterojunctions was systematically investigated using X-ray photoelectron spectroscopy (XPS). The valence band offsets (VBOs) were deduced to be 3.19 ± 0.1, 3.01 ± 0....
Article
Ultra‐high Switching Times Flexible and high‐performance selectors as critical parts has begun to attract increasing attention for suppressing the interferent current and enabling precise addressing in high‐density array integration of memories and sensors. In article number 2100771, Chen Wang, Zhenxuan Zhao, and colleagues present a flexible thres...
Article
A novel integration scheme of postgate single diffusion break (PG-SDB) has been proposed to enhance channel stress for Si gate-all-around (GAA) nanosheet field-effect transistors (NS-FET), based on TCAD simulations. Compared to conventional SDB and self-aligned SDB (SA-SDB), the proposed PG-SDB scheme implements SDB module after the replacement met...
Article
With the increased device integration density in advanced semiconductor technologies, the layout-dependent effects (LDEs) have become critical affecting both device-level and circuit-level performance. In this work, we report an impact study of LDEs on 14-nm FinFET combinational standard cells to facilitate the process of design-technology co-optim...
Article
We report a halide perovskite based flexible threshold-switched memristor with ultra-high speed as an artificial neuron that exhibits excellent leaky integrate-and-fire dynamics and strength-modulated spike frequency response performance.
Article
In this work, multiple time-dependent gate breakdown (BD) experiments are performed on p-GaN gate high-electron-mobility transistors (HEMTs) under constant gate voltage stress. Progressive gate BD behaviors are observed during the time-dependent failure process. It is found that the time-to-BD ( $\textit{t}_{\text{BD}}$ ) has a positive dependence...
Article
To satisfy the demand of high-speed and low-power memory in the field of integrated circuits, different elements doped HfO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> ferroelectric tunnel junctions have been developed. In this work, we investigate the annealing atmosphere effects on the fer...
Article
HfO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> based ferroelectric materials have great application potential in ferroelectric tunneling junction. Here, the low temperature annealed Zr-Rich Hf <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x<...
Article
Neuromorphic computing systems based on artificial synapses have showed considerable potential in the field of brain-like research. Herein, a two-terminal artificial synaptic device with photoelectric dual modulation was proposed, which has the advantages of simple fabrication process and high integration density. Under photoelectric stimulation, t...
Article
Field-effect transistors (FETs) are the main building block of microelectronic devices. For most of the FETs, the conduction channel relies on either n-type or p-type semiconductor materials. Recent advances in 2D materials offer an opportunity to form van der Waals heterojunction-based FETs with novel electrical performance. Here, a MoS2/WSe2 hete...
Article
for 5 μm diameter micro bumps, the interfacial intermetallic compounds (IMCs) seriously affects the interconnection performance of micro bumps. In this paper, we focused on the discussion of the growth and control mechanism of IMCs of 5um diameter micro bumps at different temperatures and durations. The growth mechanism and morphology of Ni3Sn4 IMC...
Article
Flexible electronics are essential for wearable setup. Due to the high nonlinear property, threshold switching (TS) selectors can effectively suppress interference currents and are compatible to large-scale integration, enabling them to be promising for circuit applications. However, it is still a big challenge to develop flexible TS selectors with...
Article
In this letter, we report a monolithically photonic integrated device based on the configuration of an InGaN/GaN micro-light-emitting diode ( $\mu $ LED) in series with an AlGaN/GaN high-electron-mobility transistor (HEMT). As an ultraviolet phototransistor, the HEMT unit can act as both the optical and the electrical input ports of this integrate...
Article
In this work, we report high-performance amorphous indium gallium zinc oxide (a-IGZO) thin-film transistors (TFTs) with atomic layer deposited Al <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</s...
Article
In conventional metal‐oxide‐semiconductor field‐effect transistors, the subthreshold slope (SS) is limited by the Boltzmann distribution and the loss of gate control with the miniaturization of integrated circuits being an insurmountable ceiling for the huge demand of low‐power, high‐density electronic devices. Negative capacitance field‐effect tra...
Article
Full-text available
The fast development in microcontroller unit (MCU) technology has urged continuous decreasing in power consumption by different assignment of operating status among devices. In this work, we focused on the ultrahigh Vth (UHVT) transistor and used gate oxide thickness and Vth implantation co-optimization to minimize the gate leakage current towards...
Article
The ferroelectricity of Zr-doped HfO₂ (HZO) thin films induced by low thermal budget annealing provides great potential to implement the ferroelectric functionalities into the back end of line (BEOL) process of the standard CMOS integrated circuits. However, most of previous works need high temperature annealing or long time annealing to acquire fe...