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The effective control of the sample concentration within droplets is essential in a broad range of assays in chemistry and biochemistry. Here we provide an electrical method for producing batches of aqueous droplets with various chemical concentrations by exploiting fixed-potential induced-charge electroosmosis (ICEO) flow around a bipolar electrode. By applying an AC electric signal to the bipolar electrode and changing the zeta potential on it, the bipolar electrode acts as a gate electrode for generating asymmetric ICEO flow. The ICEO flow induced transverse vortexes interact with two parallel laminar streams with different chemical compositions. Controlled mixing of the aqueous solutions can be achieved by adjusting the shape and size of the asymmetric vortexes

A novel inverse photoconductivity horizon in perovskite photo-memristor applications with various iodine concentrations, electrodes, and modified layers.

Compositional engineering with the addition of organic and inorganic cations is regarded as an effective way to improve the performance of perovskite solar cells (PSCs). However, exploration of triple-mixed cations in PSCs is still in its initial stage. In this study, triple cations of MA+, FA+, and Gua+ are mixed into perovskite and moulded into a 3D structure by the two-step deposition method, thus proving the feasibility of the triple-cation-based perovskite layer. Through the results of X-ray diffraction (XRD), scanning electron microscope (SEM), and Photoluminescence (PL) tests, Guay(FAMA)1-yPbIxCl3-x perovskite crystallisation was observed. The triple-mixed, cation-based perovskite film exhibits improved crystal quality, larger grain size, and fewer trap densities, all of which are positive for final power conversion efficiency (PCE) and stability. Based on the optimised MA+ and FA+ component ratio, the PSC showed the best performance with a GuaI doping concentration of 10%. The introduction of GuaI further improves the performance of devices by the passivation of defects and suppression of nonradiative recombination. The final PSCs displayed the best PCE (21.3%), as well as enhanced stability.

AlGaN/GaN-Si based MIS-HEMTs are considered as the popular candidates for application in the 5G communication system due to their competitive characteristics and low cost. Ohmic contact, as an important fabrication process, significantly affects the performance of the device. In this study, the ohmic contact process, including the SiN passivation layer etching, surface treatment, and barrier layer etching, was studied in detail in order to effectively optimize the device performance. It is observed that the sample with the SiN passivation layer etched by the magnetic neutral loop discharge (NLD) resulted in a lower contact resistance as compared to the reaction ion etching (RIE). The sample surface treated with the O plasma and pickled in the HCl:H2O = 1:10 liquid could effectively remove the pollutants and oxides from the surface, thus, correspondingly presenting a lower ohmic contact resistance as compared to the N2 plasma. Meanwhile, an optimum etching depth was developed with the ICP process for 6 min with an etching speed of 1.6 nm/min. A contact resistance of $0.76~\Omega \cdot \text {mm}$ and square resistance of 274.63 ohm/sq were observed under the above-mentioned optimized ohmic contact process. The AlGaN/GaN-Si MIS-HEMT with gate length of $0.5~\mu \text{m}$ , gate-source space of $1~\mu \text{m}$ , gate-drain space of $2.5~\mu \text{m}$ , and gate width of $100~\mu \text{m}$ was fabricated using the optimized process. A saturation current density of 794.30 mA/mm and the maximum transconductance of 16.86 mS were observed. The findings in this study provide the experimental basis for the manufacturing of AlGaN/GaN-Si based MIS-HEMTs for RF applications.

Flowering time is known to be regulated by numerous pathways, such as the autonomous, gibberellin, aging, photoperiod-mediated, and vernalization pathways. These regulatory mechanisms involve both environmental triggers and endogenous hormonal cues. Additional flowering control mechanisms mediated by other phytohormones, such as auxin, are less well understood. We found that in cultivated strawberry (Fragaria × ananassa), the expression of auxin response factor4 (FaARF4) was higher in the flowering stage than in the vegetative stage. Overexpression of FaARF4 in Arabidopsis thaliana and woodland strawberry (Fragaria vesca) resulted in transgenic plants flowering earlier than control plants. In addition, FveARF4-silenced strawberry plants showed delayed flowering compared to control plants, indicating that FaARF4 and FveARF4 function similarly in regulating flowering. Further studies showed that ARF4 can bind to the promoters of the floral meristem identity genes APETALA1 (AP1) and FRUITFULL (FUL), inducing their expression and, consequently, flowering in woodland strawberry. Our studies reveal an auxin-mediated flowering pathway in strawberry involving the induction of ARF4 expression.

With the development of semiconductor technology, the size of traditional metal oxide semiconductor field effect transistor devices continues to decrease, but it cannot meet the requirements of high performance and low power consumption. Low power tunneling field effect transistor (TFET) has gradually become the focus of researchers. This paper proposes a novel T-shaped gate TFET based on the silicon with the negative capacitance (NC-TGTFET). On the basis of TGTFET, ferroelectric material (HZO) is used as gate dielectric. The simulation results show that, compared with the traditional TGTFET, the opening order and sensitivity of the two tunneling junctions are different. The influences of thickness and the doping concentration of pocket and ferroelectric material properties on the characteristics of NC-TGTFET is also discussed by Sentaurus simulation tool. Furthermore, the negative capacitance of ferroelectric material makes NC-TGTFET have a very steep subthreshold swing (18.32 mV/dec) at the range of drain current from 1 × 10-15to 1 × 10-7Aμm-1. And the on-state current (Vg= 0.5 V,Vd= 0.5 V) is 1.52 × 10-6Aμm-1.

Foamed concrete (FC) was prepared from raw materials of vanadium tailings (VTs), reservoir sediment (RS), and phosphogypsum (PG). The physicochemical properties of the raw materials were studied by using X-ray diffraction (XRD), X-ray fluorescence (XRF) analysis, and inductively coupled plasma emission spectrometer (ICP-OES). The preparation and properties of FC were investigated by particle size analysis and strength test. The hydration products and microstructure of FC were analyzed by XRD and field emission scanning electron microscopy (FE-SEM). The results show that when the specific surface area (SSA) of VTs is 768 m2·kg−1 and the content is 40%, the products with a compressive strength of 3.56 MPa and density of 619.1 kg·m−3 meet the requirements of JG/T 266-2011 standard on FC of grades A06 and C3.0; the main mineral phases in the products are calcium silicate hydrate (C-S-H) gel, ettringite (AFt), and calcite, as well as the residual mineral phases after the system reaction include quartz, orthoclase, mullite, pyrite, and PG.

Using microfluidic technology to achieve integrated chip cooling is becoming a promising method to extend Moore law effective period. The thermal management is always critical for 3D integrated circuit design. Hot spots due to spatially non-uniform heat flux in integrated circuits can cause physical stress that further reduces reliability. The critical point for chip cooling is to use microfluidic cooling accurately on the hot spots. First, based on electro-wetting on dielectric, the paper presents an adaptive chip cooling technique using the digital microfluidics. Then, a two-plans 3D chip cooling model has been given with its working principle and characteristics. And single plan chip cooling model is presented, including its capacitance performance and models. Moreover, the dentate electrode is designed to achieve droplet continuing movement. Next, the ant colony optimization is adopted to get optimal route during electrode moving. Last, the experiments demonstrate the adaptive chip cooling technique proposed in this paper is effective and efficiency.

Perovskite solar cells (PSCs) have become an impressive research focus due to their unique properties, where their interface transport layers are important for an enhancement in efficiency and stability. In this study, we demonstrate that a lithium (Li) and cobalt (Co) co-doped NiOx hole transport layer can greatly enhance the device performance of inverted planar heterojunction PSCs. Compared to the pristine NiOx films and Li doped NiOx HTLs, co-doping with a certain amount of Li and Co further increased the electrical conductivity and hole mobility of the NiOx film. Consequently, the power conversion efficiency (PCE) of the PSCs greatly improved from 17.4% to 20.1% when they were co-doped with 10% Li and 5% Co. Moreover, the short-circuit current density (Jsc) increased from 22.7 mA cm−2 to 23.8 mA cm−2, the open-circuit voltage (Voc) was enhanced from 1.05 V to 1.09 V, and the fill factor (FF) was enhanced from 0.73 to 0.78 for the PSCs. These results demonstrate that the co-doping of Li and Co can be an effective strategy improving the performance of PSCs.

We realize a controllable metallic behavior on stoichiometric (100) SrTiO3 single crystals via KrF laser irradiation, which strongly depends on vacuum and laser energy density. Moreover, this metallic conduction is caused by oxygen deficiency and can be manipulated by light illumination and electrostatic gating field. The laser-irradiated SrTiO3 shows sensitive persistent photoresponse with a relative change in the resistance of about 45% at 20 K for a 360 nm light. In addition, the conduction can also be modulated to a lower (higher) state by a positive (negative) backgate. Our results highlight the possibility of tuning the electrical properties of oxides.

Roots and leaves are both important organs of the plant and central to the life strategy, which are crucial for plant survival and perform a wide range of functions. However, the mechanism of miR167 and its target gene, auxin response factor6 (ARF6), regulating the development of roots and leaves for strawberry, has not yet been characterized. In this study, miR167b precursor and FveARF6 were isolated from the woodland strawberry ‘Ruegen’ (Fragaria vesca), and RLM-5′ RACE showed that FveARF6 transcript is cleavage target of FvemiR167b. Both FvemiR167b and its target gene expressed in different organs of strawberry, and the expression of FveARF6 could be induced by IAA. Overexpressing-FvemiR167b and RNAi-FveARF6 transgenic lines both exhibited an increase in the number of roots and leaves of strawberry. Transactivation analysis showed that FveARF6 presented transcriptional activation activity in yeast. Gene expression analysis indicated that the transcript levels of the strawberry GH3 family also declined in RNAi-ARF6 transgenic plants compared with the wild-type controls. The GH3 family promoter sequences of strawberry had at least one AuxRE element. Taken together, our results reveal that FvemiR167b represses the expression of FveARF6 gene to cause the roots and leaves of strawberry to grow in number, which can likely further regulate the growth of the plant by GH3 family. This will help us understand the molecular mechanism of miR167-ARF6 module in woodland strawberry.

In the context of the COVID-19 epidemic, enhancing the transport of analyte to a sensor surface is crucial for rapid detection of biomolecules since common conditions, including low diffusion coefficients, cause inordinately long detection times. Integrated microfluidic immunoassay chips are receiving increasing attention for their low sample volume and fast response time. We herein take advantage of asymmetric ICEO flow at a bipolar sinusoidal electrode to improve the rate of antibody binding to the reaction surface based on finite element modeling. Three different microfluidic cavities are proposed by changing the positions of the surface reaction area. We further investigate the relationship between binding enhancement and reaction surface positions, Damkohler number, and the voltage and frequency of the AC signal applied to the driving electrodes. Furthermore, the influence of the AC signal applied to the sinusoidal bipolar electrode on antigen–antibody-binding performance is studied in detail. Above all, the simulation results demonstrate that the microfluidic immune-sensor with a sinusoidal bipolar electrode could not only significantly improve the heterogeneous immunoassays but also enable efficient enhancement of assays in a selected reaction region within the micro-cavity, providing a promising approach to a variety of immunoassay applications, such as medical diagnostics and environmental and food monitoring.

Since the power conversion efficiencies of organic-inorganic hybrid perovskite solar cells have a rapid development due to their high light absorption coefficient, tunable band gap and low fabrication cost, they have received much attention. The thin film formation and properties have significant effects on the final device performance. While how to control the thin film evolution and introduce film passivation is a critical issue to improve the device efficiency. In this study, we studied the controlled in-situ PbI2 formation during the thin film evolution, and its effect on thin film properties, as well as their passivation effects on the photovoltaic device performance. The final thin film properties are critically related with the precursor used and chlorine inclusion could change the final thin film compositions, and affect the solar cell performance. We further perform a secondary passivation by reacting the excess PbI2 with large organic cation to form 2D perovskite. Based on in-situ PbI2 passivation and secondary 2D perovskite passivation, the devices exhibit a higher PCE of 21.1% and excellent Voc of 1.14 V.

Due to its unique I-V property, memristor is considered to be the key device for artificial intelligence application. Among the alternative memristor materials, organometal trihalide perovskite (OTP) follow with interest in photoelectric coupling area with excellent light absorption ability. However, the power consumption of OTP memristor still remains to be reduced. Here, Cs0.05(FAxMA1−x)0.95PbIyBr3−y (CsFAMAPbIBr) with prominent photoresponse property is used as the functional layer of the memristor. Maximum high resistance state (HRS)/low resistance state (LRS) (~100) and maximum power of 9.8 × 10−9 W is reached under small voltage (−1 V~1 V) with W/OTP/Al structure. Since the oxide modification layer acts as a series resistance for the device, when 90 nm thickness of zinc oxide layer is added to the W/OTP interface, the power consumption of the device is reduced by an order of magnitude. Then, the maximum power of the device decreases by two orders of magnitude (to 2.5 × 10−11 W) under 2 mW/cm2 light condition, and the phenomenon called negative photoconductance (NPC) effect that defined as an increase in resistance upon exposure to illumination. Through the optical and oxide modification, OTP memristor with low power consumption is achieved.

MEMS phase shifter has many advantages as the ‘steering wheel’ of phased array antenna beam steering. The deformation of mechanical structures of MEMS phase shifter influenced by the complex environmental factors, which became the biggest obstacle to further enhance the performance of phased array antennas. The electromechanical coupling model between the bridge height and phase shift of the distributed MEMS phase shifter is developed. The coupling model could be used to predict the phase error and determine the bridge height tolerance for the deformed MEMS phase shifter. The simulation results of four-bit distributed MEMS phase shifter with 15 bridges illustrate the validity of coupling model and demonstrate the application potential for engineering design and test.

Microfluidics offer microenvironments for reagent delivery, handling, mixing, reaction, and detection, but often demand the affiliated equipment for liquid control for these functions. As a helpful tool, the capillary pressure control valve (CPCV) has become popular to avoid using affiliated equipment. Liquid can be handled in a controlled manner by using the bubble pressure effects. In this paper, we analyze and categorize the CPCVs via three determining parameters: surface tension, contact angle, and microchannel shape. Finally, a few application scenarios and impacts of CPCV are listed, which includes how CPVC simplify automation of microfluidic networks, work with other driving modes; make extensive use of microfluidics by open channel, and sampling and delivery with controlled manners. The authors hope this review will help the development and use of the CPCV in microfluidic fields in both research and industry.

Memristors are new type of circuit element with the characteristics of both integrated computing and storage, which can promote the development of artificial intelligence and memory- computing fusion technology. In this manuscript, a novel triple cation Organic-inorganic hybrid perovskite (OHP) based optoelectronic coupling memristors with structure of FTO/TiO2/Cs0.05(FAxMA1−x)0.95PbBryI3−y/Al were fabricated, hysteresis loops with low power consumption, high HRS/LRS ratio and obvious light response are presented. Besides, capacitive coupling behaviors are observed in current curves. By changing voltage or light condition, memristors can evolve from capacitive behavior to pure memristive behavior. Physical mechanisms are discussed to explain this phenomenon. This work opens up a way in improving the resistive switching performances of OHP memristors, and can be of great benefit to the potential application in neuromorphological analysis.

Because of the high electron mobility and electron velocity in the channel, InAs/AlSb high electron mobility transistors (HEMTs) have excellent physical properties, compared with the other traditional III-V semiconductor components, such as ultra-high cut-off frequency, very low power consumption and good noise performance. In this paper, both the structure and working principle of InAs/AlSb HEMTs were studied, the energy band distribution of the InAs/AlSb heterojunction epitaxy was analyzed, and the generation mechanism and scattering mechanism of two-dimensional electron gas (2DEG) in InAs channel were demonstrated, based on the software simulation in detail. In order to discuss the impact of different epitaxial structures on the 2DEG and electron mobility in channel, four kinds of epitaxies with different thickness of InAs channel and AlSb upper-barrier were manufactured. The samples were evaluated with the contact Hall test. It is found the sample with a channel thickness of 15 nm and upper-barrier layer of 17 nm shows a best compromised sheet carrier concentration of 2.56 &times, 1012 cm&minus, 2 and electron mobility of 1.81 &times, 104 cm2/V&middot, s, and a low sheet resistivity of 135 &Omega, /□, which we considered to be the optimized thickness of channel layer and upper-barrier layer. This study is a reference to further design InAs/AlSb HEMT, by ensuring a good device performance.

With the rapid development of semiconductor process, both tunneling field effect transistor (TFET) and negative capacitance field effect transistor (NCFET) are regarded as the effective low power devices. In this paper, a novel silicon-based dual source U-shaped channel TFET with negative capacitance (NCDU-TFET) is proposed and investigated by Synopsys Sentaurus TCAD. We pick ferroelectric material (Hf0.5Zr0.5O2) as the gate dielectric. The higher electric field caused by negative capacitance effectively increases the tunneling rate, so the super-steep subthreshold swing (SS) and higher on-state current are obtained for NCDU-TFET. Besides, the impacts of device parameters including gate dielectric layer thickness, coercive electric field and remnant polarization are also analyzed systematically in this paper. The simulation results indicate the average SS of NCDU-TFET is 17.04mV/dec, which is much lower than that of DU-TFET. And the on-state current of NCDU-TFET is nearly three orders of magnitude higher than that of DU-TFET. So NCDU-TFET has the potential to be used as a low-power component for large-scale integrated circuits.

Organic-inorganic halide perovskites (OHPs) have been proven to possess unique optical and electrical properties, and achieved more extensive application as excellent materials for memristors in recent years. Based on the traditional OHP-based memristors, the intermediate layer of the memristor was prepared using yttrium oxide (Y2O3)/OHP stacking structure in this manuscript. The potential barrier between Y2O3and perovskite is relatively high (ΔEC = 2.13 eV) which leads to comparatively low current of the memristor, thus the power consumption can be reduced. Besides, by changing the external light conditions, one can realize sharp or slow switch between high resistance state (HRS) and low resistance state (LRS), so as to meet the requirement of multilevel data storage, which indicates its promising application prospect in information storage and biological simulation. In addition, based on characteristics of photoelectric coupling, the Y2O3/OHP memristor can also achieve the advantage of adjustable threshold voltage. The transition of HRS and LRS can be realized by changing the illumination condition at any voltage, which means the set and reset voltage are not fixed, so that the memristor with adjustable threshold voltage can adapt to various working conditions.

HfAlO/InAlAs metal–oxide–semiconductor capacitor (MOS capacitor) is considered as the most popular candidate of the isolated gate of InAs/AlSb high electron mobility transistor (HEMT). In order to improve the performance of the HfAlO/InAlAs MOS-capacitor, samples are annealed at different temperatures for investigating the HfAlO/InAlAs interfacial characyeristics and the device’s electrical characteristics. We find that as annealing temperature increases from 280 °C to 480 °C, the surface roughness on the oxide layer is improved. A maximum equivalent dielectric constant of 8.47, a minimum equivalent oxide thickness of 5.53 nm, and a small threshold voltage of –1.05 V are detected when being annealed at 380 °C; furthermore, a low interfacial state density is yielded at 380 °C, and this can effectively reduce the device leakage current density to a significantly low value of 1 × 10−7 A/cm2 at 3-V bias voltage. Therefore, we hold that 380 °C is the best compromised annealing temperature to ensure that the device performance is improved effectively. This study provides a reliable conceptual basis for preparing and applying HfAlO/InAlAs MOS-capacitor as the isolated gate on InAs/AlSb HEMT devices.

MicroRNAs are endogenous small non-coding RNAs that negatively regulate mRNAs, mainly at the post-transcriptional level, and play an important role in resistance response of plants. To date, there are few reports on resistance response of strawberry miRNAs to pathogens. In this study, using high-throughput sequencing, 134 conserved and 35 novel miRNAs were identified in six libraries within the treatment of Botrytis cinerea. A total 497 potential target genes were predicted using Fragaria vesca genome. Most of the differential expressed miRNAs in strawberry fruits were up-regulated in early libraries and down-regulated in late libraries. PIRL, the target gene of miR5290a, showed the opposite expressed trend compared with miR5290 from T1 to T3 libraries, and functional analysis of the PIRL gene shows that it has obvious resistance to B. cinerea in the strawberry fruits with overexpressed PIRL gene. We speculate that miR5290a negatively regulates its target gene PIRL to increase resistance to pathogen infection, and further analysis of PIRL function is meaningful for studying the plant-pathogen relationship and improving strawberry fruit quality and yield.

Using microfluidic cooling to achieve thermal management of three-dimensional integrated circuits (ICs) is recognized as a promising method of extending Moore law progression in electronic components and systems. Since the U.S. Defense Advanced Research Projects Agency launched Intra/Inter Chip Enhanced Cooling thermal packaging program, the method of using microfluidic cooling in 3D ICs has been under continuous development. This paper presents an analysis of all publications available about the microfluidic cooling technologies used in 3D IC thermal management, and summarized these research works into six categories: cooling structure design, co-design issues, through silicon via (TSV) influence, specific chip applications, thermal models, and non-uniform heating and hotspots. The details of these research works are given, future works are suggested.

Background Curcumin is a polyphenolic compound with potent chemopreventive and anti-cancer efficacy. Purpose To explore the potential anti-metastasis efficacy of curcumin in breast cancer stem-like cells (BCSCs), which are increasingly considered to be the origin of the recurrence and metastasis of breast cancer. Methods A CCK8 assay was performed to evaluate cell viability, and a colony formation assay was conducted to determine cell proliferation in MCF-7 and MDA-MB-231 adherent cells. Transwell and wound healing assays were used to detect the effect of curcumin on cell migration and invasion in MDA-MB-231 cells. Mammospheres were cultured with serum free medium (SFM) for three generations and the BCSC surface marker CD44+CD24−/low subpopulation was measured by flow cytometry. Mammosphere formation and differentiation abilities were determined after cell treatment with curcumin. Then, a reverse transcription-quantitative polymerase chain reaction assay was conducted to detect the relative mRNA level of epithelial-mesenchymal transition (EMT) marker genes and western blot analysis was performed to determine the protein expression of stem cell genes in mammospheres treated with curcumin. Results Curcumin exhibited anti-proliferative and colony formation inhibiting activities in both the MCF-7 and MDA-MB-231 cell lines. It also suppressed the migration and invasion of MDA-MB-231 cells. The CD44+CD24−/low subpopulation was larger in mammospheres when MCF-7 and MDA-MB-231 adherent cells were cultured with SFM. Further studies revealed that curcumin inhibited mammosphere formation and differentiation abilities. Moreover, curcumin down-regulated the mRNA expression of Vimentin, Fibronectin, and β-catenin, and up-regulated E-cadherin mRNA expression levels. Western blot analysis demonstrated that curcumin decreased the protein expression of stem cell genes including Oct4, Nanog and Sox2. Conclusion The results of the present study suggest that the inhibitor effects of curcumin on breast cancer cells may be related to resistance to cancer stem-like characters and the EMT process. These data indicate that curcumin could function as a type of anti-metastasis agent for breast cancer.

Fourier transform infrared spectroscopy is a widely used instrument to analyze and test different materials including organic and inorganic. Most of current commercial Fourier transform infrared spectrometers are limited in miniaturization and scanning velocity by their macroscopic components. MEMS FTIR spectroscopy is one of the important applications of translational actuator-driven systems by using MEMS technology. The critical component in MEMS FTIRs is the large displacement translating micromirror and its actuator. The paper presents a large displacement and high-surface quality micromirror. The micromirror consists of a micromagnetic actuator and a micromirror plate. The mirror plate and the actuator are fabricated separately and bonded together afterwards, and its size is 3.6 × 3.6 mm2 high-surface quality square mirror plate and a 1cm2 moving part. The microactuator’s moving part is fabricated using MetalMUMPS, and its fixed part includes a ring permanent magnet and a solenoid to realize a large displacement. The mirror plate is fabricated using polished silicon coated with metal layer with high-surface prototypes that are fabricated and experimentally tested. A maximum stroke of 400 μm has been achieved in pull-in whereas only 140 μm stroke have been measured for a 4 to 5-volt DC-controlled displacement, and the resonance frequency is 10 Hz.

The position error of array antenna significantly deteriorates the gain and sidelobe of the array, which seriously hinders the realization of high performance of communication antenna for Internet of Things (IoT). Based on the sensitivity analysis theory, the sensitivity of the array radiation field with respect to the position of the antenna element is derived. Besides, a novel design method of position tolerance for array antenna is proposed and applied to a 20×20 planar array. Compared with the array designed by traditional method, the gain loss is basically the same (being 0.5 dB), while the peak sidelobe level is lowered by 1.937 dB (φ=0°)/1.586 dB (φ=90°). Besides, the uncertainty analysis results show that the newly designed array has a much higher chance to achieve the desired performance, which fully demonstrates the innovation and effectiveness of the new method.

ultivariate process capability indices (MPCI), as an important means of statistical process control (SPC), can be used to ensure the high reliability of semiconductors manufacturing process. However, the reasonable sampling number is an important factor when considering MPCI values. As general, the large sample number requires much effort and time, or even cannot be achieved. In this paper, we evaluated the impact of different sample size on the calculations of multivariate process capability indices using simulation and analyses. After getting enough data and choosing disparate sample numbers, corresponding multivariate process capability indices can be obtained, which demonstrate the relationship between sampling numbers and calculation results. The conclusions have critical guiding significance for manufacturing semiconductors with high reliability requirement.

Layout parasitic has crucial influence on the performance of analogue integrated circuits. The paper presents a performance-constrained analogue layout retargeting and optimisation scheme. Geometric programming (GP), is a kind of nonlinear optimisation problem, is used in the method, which can be transferred or fitted into a convex optimisation problem based on mathematical analyses. Then, a global optimum solution can be achieved. To achieve the desired circuit performance, performance sensitivities based on layout parasitic are carried out in the analogue layout optimisation. In addition, a central difference method is applied to control parasitic-related layout geometries by constructing a set of performance constraints subject to maximum performance deviation. At last, a two-stage Miller-compensated operational amplifier and a single-ended folded cascode operational amplifier are simulated with the proposed scheme. The automatically generated target layouts can satisfy performance constraints to ensur...

To satisfy the requirements of complex and special analog layout constraints, a new analog layout retargeting method is presented in this article. Our approach uses geometric programming (GP) to achieve new technology design rules, implement device symmetry and matching constraints, and manage parasitics optimization. The GP, a class of nonlinear optimization problem, can be transferred or fitted into a convex optimization problem. Therefore, a global optimum solution can be achieved. Moreover, the GP can address problems with large-scale variables and constraints without setting an initialization variable range. To meet the prerequisites of the GP methodology for analog layout automation, we propose three kinds of mathematical transformations, including negative coefficient transformation, fraction transformation, and maximum of posynomial transformation. The efficiency and effectiveness of the proposed algorithm, as compared with the other existing methods, are demonstrated by a basic case-study example: a two-stage Miller-compensated operational amplifier and a single-ended folded cascode operational amplifier.

High aspect ratio units are necessary parts of complex microstructures in microfluidic devices. Some methods that are available to achieve a high aspect ratio require expensive materials or complex chemical processes; for other methods it is difficult to reach simple high aspect ratio structures, which need supporting structures. The paper presents a simple and cheap two-step Polydimethylsioxane (PDMS) transferring process to get high aspect ratio single pillars, which only requires covering the PDMS mold with a Brij@52 surface solution after getting a relative PDMS mold based on an SU8 mold. The experimental results demonstrate the method efficiency and effectiveness.

Heterointerfaces between two insulators play a central role in the study of oxide electronics owing to a spectrum of emergent properties. Manipulating transport of the interface by light can result in significant modulation of the ground state and excite localized states. However, their dynamics and mechanisms of photogenerated carries remain unclear. Here, this study presents the dynamics of carrier density and mobility under and after light illumination by Hall effect over time. It is discovered that the density and mobility after light illumination obey a stretched exponential expression, further indicating that the variation of mobility caused by the electron-electron scattering plays an important role in the recovery process in addition to the reduction of carrier density. Meanwhile, a non-linear Hall resistance at the LaAlO3/SrTiO3 interface under the illumination of a 360 nm laser at low temperature is observed. Furthermore, the gating effect can tune the recovery process after light illumination and induce a disappearance of non-linear Hall resistance. The results provide the experimental support for detailed mechanisms of the nonequilibrium process and developing of all-oxide electronic devices based on heterointerfaces.Heterointerfaces between two insulators play a central role in the study of oxide electronics owing to a spectrum of emergent properties. Manipulating transport of the interface by light can result in significant modulation of the ground state and excite localized states. However, their dynamics and mechanisms of photogenerated carries remain unclear. Here, this study presents the dynamics of carrier density and mobility under and after light illumination by Hall effect over time. It is discovered that the density and mobility after light illumination obey a stretched exponential expression, further indicating that the variation of mobility caused by the electron-electron scattering plays an important role in the recovery process in addition to the reduction of carrier density. Meanwhile, a non-linear Hall resistance at the LaAlO3/SrTiO3 interface under the illumination of a 360 nm laser at low temperature is observed. Furthermore, the gating effect can tune the recovery process after light illumination a...

Persistent magnetoresistance effects in the phase-separated Pr0.65(Ca0.25Sr0.75)0.35MnO3/SrTiO3 and Pr0.65(Ca0.25Sr0.75)0.35MnO3/0.7PbMg1/3Nb2/3O3–0.3PbTiO3 heterostructures under a low magnetic field are investigated. It is observed that the persistent magnetoresistance effects decrease with increasing temperatures and the values for the heterostructures on 0.7Pb(Mg1/3Nb2/3)O3–0.3PbTiO3 and SrTiO3 substrates are about 86.6% and 33.2% at 40 K, respectively. More interestingly, the applied electric field on the 0.7PbMg1/3Nb2/3O3–0.3PbTiO3 substrate can suppress the persistent magnetoresistance effect, indicating that different energy landscapes can be dramatically modulated by the piezo-strain. These results are discussed in terms of the strain-induced competition in the ferromagnetic state and the charge-ordering phase by the energy scenario, which provide a promising approach for designing devices of electric-magnetic memories in all-oxide heterostructures.

This paper presents an automatic peak-valley current mode step-up/step-down DC-DC converter with high efficiency, small output voltage ripple, and fast transient response. The converter could automatically changes between peak and valley current modes by using the proposed control scheme. The switching loss is reduced by operating in pure buck or pure boost mode, and the conducting loss in transition mode is reduced by decreasing the average inductor current. The output voltage ripple is alleviated by introducing two transition modes. A fast load transient response is achieved with a small overshoot and undershoot voltage. The proposed converter has been designed with a standard 0.5µm CMOS process. The output voltage can be regulated from 2.5V to 5.5V with the input voltage in the same range. The output voltage ripple is less than 10mV in all operation modes. The maximum load current is 600mA, and the peak efficiency is 95%.

In this letter, we report the photoinduced effect modulated by different electric fields in the Pr0.65 (Ca0.75Sr0.25)0.35MnO3/0.7PbMg1/3Nb2/3O3-0.3PbTiO3 heterostructure. The film exhibits a decrease in the resistance up to five orders of magnitude by enhancing applied electric fields, combined with an electric-field-induced insulator-to-metal transition. More interestingly, a reversible bistability arises in the photoinduced change in resistance at T

To satisfy the requirements of complex and special analog layout constraints, a constrains symbolization method based on geometric programming for analog layout retargeting is presented in this paper. The approach is to build symbolic template for layouts, then uses geometric programming (GP) to achieve new technology design rules, implement device symmetry and matching constraints, and manage parasitics optimization. The GP, a class of non-linear optimization problem, can be transferred or fitted into a convex optimization problem. Therefore, a global optimum solution can be achieved. The symbolization method ensures the layout retargeting automatically. The efficiency and effectiveness of the proposed algorithm, as compared with the other existing methods, are demonstrated by a basic case-study example and a two-stage Miller-compensated operational amplifier.

Heuristic teaching method is one of the most important teaching methods nowadays. In the paper, the existing problems using tradition teaching method in information technology have been analyzed. Then, paper shows the procedure of applying heuristic teaching in information technology, which includes searching close relationship, explaining definition, creating problem and teaching problem solving idea. Finally, the specific application in information technology is given. Results shows the teaching efficiency and effectiveness has been improved.

Process capability ultimately decides process quality level. Based on analyzing process capability index (PCI), Process capability may be effectively assured. For the multivariate manufacturing processes, tremendous difficulties are often encountered when one attempts to measure the process capability by directly extending the univariate approach. After analyzing the multivariate Cpm method (Chan et al. 1991), the paper presents a spatial multivariate PCI method, which can solve multivariate off-centered case and may provide references for assuring and improving process quality level while achieving overall evaluation of process quality. At last, examples for calculating multivariate PCI are given and the experimental results show that the systematic method presented is effective and actual.

Process quality ultimately decides on the quality of electronic products. Based on analyzing and improving process capability index (PCI), microelectronics process quality of electronic products may be effectively assured. Nowadays with the rapid development in microelectronics process, Quality evaluation of processes concerns more than one quality characteristics, microelectronics process quality evaluation concerns multi quality characteristics, therefore univariate PCI is difficultly used to synthetically analyze microelectronics process quality. The paper presents a multivariate PCI based on weight factor, which provides references for assuring and improving process quality while achieving overall evaluation of process quality and is not limited to the variable number. An example of calculating multivariate PCI (MPCI) is given. Real application shows that the method presented is effective and actual.

Bulk-driven MOSFET technique meets the low-voltage and low-power requirements demanded in the modern analog circuit design. Due to submicron/nanometer technologies and critical short-channel effects, choosing a suitable MOSFET model for circuit design becomes increasingly important. However, the conventional MOSFET models normally set up for the typical gate-driven applications may not perform correctly and accurately for the bulk-driven applications in the advanced technologies. In this paper, three most widely used MOSFET models, including BSIM, EKV, and PSP, have been extracted for the modern technologies and used in the simulation of bulk-driven applications. Measurement data of fabricated devices are compared with simulation results from distinct models. Several critical MOSFET parameters have been chosen to compare and analyze MOSFET characteristics. The experimental results demonstrate the advantages of the bulk-driven technique compared with the gate-driven scheme. Finally, the performance of distinct MOSFET models is summarized in order to provide analog circuit designers with practical directives.

This paper presents a current mode step-up/step-down DC–DC converter with high efficiency, small output voltage ripple, and fast transient response. The control scheme adaptively configures the converter into the proper operation mode. The efficiency is improved by reducing the switching loss, wherein the converter operates like a buck or boost converter, and conduction loss, wherein the average inductor current is reduced in transition modes. The output voltage ripple is significantly reduced by incorporating two constant time transition modes. A fast line transient response is achieved with small overshoot and undershoot voltage. An adaptive substrate selector (ASS) is introduced to dynamically switch the substrate of PMOS power transistors to the highest on-chip voltage. A lossless self-biased current sensor with high-speed and high-accuracy is also achieved. The proposed converter was designed with a standard 0.5 μm CMOS process, and can regulate an output voltage within the input voltage ranged from 2.5 V to 5.5 V. The maximum load current is 600 mA, and the maximum efficiency is 94%. The output voltage ripple is less than 15 mV in all operation modes.