Structure-dependent behaviors of diode-triggered silicon controlled rectifier under electrostatic discharge stress

The comprehensive understanding of the structure-dependent electrostatic discharge behaviors in a conventional diode-triggered silicon controlled rectifier （DTSCR） is presented in this paper. Combined with the device simulation, a mathematical model is built to get a more in-depth insight into this phenomenon. The theoretical studies are verified by the transmission-line-pulsing （TLP） test results of the modified DTSCR structure, which is realized in a 65-nm complementary metal-oxide-semiconductor （CMOS） process. The detailed analysis of the physical mechanism is used to provide predictions as the DTSCR-based protection scheme is required. In addition, a method is also presented to achieve the tradeoff between the leakage and trigger voltage in DTSCR.

Low-leakage diode-triggered silicon controlled rectifier for electrostatic discharge protection in 0.18-μm CMOS process

A diode-triggered silicon controlled rectifier (DTSCR) is being developed as an electrostatic discharge (ESD) pro- tection device for low voltage applications. However, DTSCR leaks high current during normal operation due to the Darlington effect of the triggering-assist diode string. In this study, two types of diode string triggered SCRs are designed for low leakage consideration; the modified diode string and composite polysilicon diode string triggered SCRs (MDTSCR & PDTSCR). Com- pared with the conventional DTSCR (CDTSCR), the MDTSCR has a much lower substrate leakage current with a relatively large silicon cost, and the PDTSCR has a much lower substrate leakage current with similar area and shows good leakage performance at a high temperature. Other DTSCR ESD properties are also investigated, especially regarding their layout, triggering voltage and failure current.

Multi-channel 28-GHz millimeter-wave signal generation on a silicon photonic chip with automated polarization control

We propose and experimentally demonstrate an integrated silicon photonic scheme to generate multi-channel millimeter-wave(MMW) signals for 5 G multi-user applications. The fabricated silicon photonic chip has a footprint of 1.1 × 2.1 mm^2 and integrates 7 independent channels each having on-chip polarization control and heterodyne mixing functions. 7 channels of4-Gb/s QPSK baseband signals are delivered via a 2-km multi-core fiber(MCF) and coupled into the chip with a local oscillator(LO) light. The polarization state of each signal light is automatically adjusted and aligned with that of the LO light, and then 7 channels of 28-GHz MMW carrying 4-Gb/s QPSK signals are generated by optical heterodyne beating. Automated polarizationcontrol function of each channel is also demonstrated with ～7-ms tuning time and ～27-dB extinction ratio.

Temperature Fluctuation Synthesis/Simultaneous Densification and Microstructure Control of Titanium Silicon Carbide (Ti_3SiC_2) Ceramics

A novel temperature fluctuation synthesis/simultaneous densification process was developed for the preparation of Ti3SiC2 bulk ceramics. In this process. Si is used as an in-situ liquid forming phase and it is favorable for both the solid-liquid synthesis and the densification of Ti3SiC2 rainies. The present work demonstrated that the temperature fluctuation synthesis/simultaneous densification process is one of the most effective and simple methods for the preparation of Ti3SiC2 bulk materials providing relatively low synthesis temperature. short reaction time; and simultaneous synthesis and densification. This work also showed the capability to control the microstructure, e.g., the preferred orientation, of the bulk Ti3SiC2 materials simply by applying the hot pressing pressure at different Stages of the temperature fluctuation process. And textured Ti3SiC2 bulk materials with {002} faces of laminated Ti3SiC2 grains normal to the hot pressing axis were prepared.

A New Type of Fiber-induced Optically Controllable Silicon-loaded Millimeter Waveguide Switch

In this paper,a new type of optically controllable silicon slab loaded E-plane millimeterwave rectangular waveguide switch is presented.It uses SELFOC lens to couple optical puls-es to silicon slab with optical fiber.The on/off ratio reaches 42dB,the front fringe of suchkind swith is less than 0.05μs,and the insertion loss is less than 1dB in the full band of 26.5GHz to 40GHz.

Transverse thickness difference control technology for non-oriented silicon steel

Transverse thickness difference is an important quality index of non-oriented silicon steel strips. In order to fulfill users＇ accuracy requirements on the transverse thickness of silicon steel and improve the production yield, the factors influencing transverse thickness difference were analyzed. Then the work roll shape, control strategy and incoming hot-rolled strips were optimized. Since the optimization measures were implemented in the actual production, the thickness difference of non-oriented silicon steel has been reduced greatly and fulfilled the requirements placed by users. These measures have achieved remarkable effects.

缓控释肥硅基膜材的制备与表征

以钙镁磷肥、硅丙树脂为主要原料,加入甲基硅酸钠作粘结剂,制备了缓控释肥硅基膜材,并采用撒粉离心包衣、底喷式流化床工艺制备了密封型硅钙镁磷肥、粘结型硅钙镁磷肥、改性硅丙树脂3种包膜尿素,通过静水试验研究了此3种包膜尿素的释放特征。结果表明,3种包膜尿素的释放周期分别为60、79、96 d,在水中均能保持完整球形,耐水性较好。通过扫描电镜、红外光谱、X-射线衍射法对膜材形貌特征和结构进行表征,发现钙镁磷肥和硅丙树脂为成膜材料;甲基硅酸钠作为密封剂和防水剂参与了成膜反应,有效增加了膜材的塑性和韧性,此复合材料可用作缓控释肥的胶结剂和包膜剂。

基于高斯过程回归的永磁同步电机非线性磁链辨识

在新能源汽车发展领域,以碳化硅为代表的新一代半导体功率器件正在逐步取代硅基IGBT,崭新的技术生态对电机控制性能也有了更高的要求。从传统的PI控制、直接转矩控制到模型预测控制、神经网络控制等新算法,电机参数的精准度逐渐成为电控系统进一步提升性能的关键因素。针对永磁同步电机经典线性模型受交叉饱和等非线性因素影响不能适用于复杂多变工况的问题,提出基于高斯过程回归的非线性磁链辨识方法,使用二阶广义积分器获取动态工况中的磁链数据完成系统辨识,通过仿真与实验验证了该方案的有效性及参数辨识的准确性。

配施硅肥对稻飞虱取食量、田间种群数量及水稻产量的影响

为探明增施硅肥在水稻田稻飞虱绿色防控中的作用,本文采用室内蜜露测定、田间盆拍调查等方法研究了在广西代表性土壤条件下增施硅肥对稻飞虱蜜露量、田间种群数量及水稻产量的影响。结果表明:褐飞虱Nilaparvata lugens St l和白背飞虱Sogatella furcifera Horváth在施硅量为15 kg/hm^(2)和45 kg/hm^(2)水稻上的平均蜜露量均显著低于不施硅对照。在水稻分蘖期,与不施硅对照相比,15 kg/hm^(2)施硅处理下两个试验点稻飞虱发生量均显著减少;45 kg/hm^(2)施硅处理下宾阳试验点的稻飞虱发生量显著减少,而合浦试验点在水稻分蘖盛期稻飞虱发生量虽未显著减少,但水稻分蘖后期稻飞虱发生量极显著低于不施硅对照,减少了51.03%。在水稻灌浆期,与不施硅对照相比,宾阳试验点15 kg/hm^(2)和45 kg/hm^(2)施硅处理稻飞虱的发生量均极显著减少,而合浦试验点稻飞虱发生量没有显著变化。15 kg/hm^(2)和45 kg/hm^(2)施硅处理的稻谷千粒重均显著高于不施硅对照,产量比不施硅对照提高1.88%~9.05%。增施硅肥可明显降低水稻田稻飞虱的取食量和田间种群发生量,同时在一定程度上提高了稻谷产量,因此,水稻增施硅肥有助于广西稻飞虱的绿色防控。

种衣剂减量下增施菌剂和肥料对小麦光合、产量、蚜虫及白粉病防控的影响

为探究拌种药剂减量下增施不同类型肥料对麦田蚜虫和白粉病防控及光合和产量的影响,以小麦蚜虫低感品种川麦104和高感品种内麦836为试验材料,采用大田试验,对种衣剂减量20%下,配合施用光合菌剂、微生物菌剂、硅肥或磷酸二氢钾后麦田土壤酶活性、小麦植株光合特性、病虫防治情况和产量性状的变化进行了比较分析。结果表明,拌种药剂减量20%条件下增施微生物菌剂较种衣剂常规用量处理能显著提高孕穗期川麦104的根际土壤的脲酶活性,以及内麦836的根际土壤过氧化氢酶和纤维素酶活性。在孕穗期和抽穗期,低感品种川麦104的麦蚜数量均显著低于内麦836;增施微生物菌剂和硅肥均能显著降低麦蚜和白粉病发生,对蚜虫防效和白粉病防效较常规药剂拌种用量处理分别提高8.0和10.2个百分点。拌种药剂减量20%配合施用光合菌剂、微生物菌剂、硅肥和磷酸二氢钾均能有效提高小麦旗叶氮素含量和SPAD值,改善叶片光合效率。增施硅肥下川麦104和内麦836的产量最高,较常规种衣剂用量处理分别增加16.0%和18.2%,差异均显著。以上结果说明,小麦种子种衣剂减量配合施用硅肥或微生物菌剂可有效提高麦田土壤酶活性,减少蚜虫和白粉病发生,改善小麦叶片光合特性,提高产量。

结构化控制剂对硅橡胶性能的影响

以甲基乙烯基硅橡胶为主体材料,研究结构化控制剂羟基硅油、甲氧基硅油和二甲基二乙氧基硅油对硅橡胶性能的影响。结果表明:添加结构化控制剂可以抑制硅橡胶的结构化现象,减小硅橡胶的交联程度、硬度、定伸应力、拉伸强度、回弹值和压缩永久变形,增大拉断伸长率;羟基硅油对硅橡胶结构化的抑制效果最佳,可以降低硅橡胶(捏合混炼胶)的储能模量,延长停放时间,其用量为6份时就能达到较好的效果。

基于45 nm CMOS SOI工艺的毫米波双频段低相噪压控振荡器设计

本文基于45 nm互补金属氧化物半导体绝缘体上硅工艺(Complementary Metal Oxide Semiconductor Silicon On Insulator,CMOS SOI)设计了一款支持5G毫米波24.25~27.5 GHz和37~43.5 GHz双频段的低相位噪声压控振荡器(Voltage Controlled Oscillator,VCO).基于CMOS SOI工艺良好的晶体管开关特性,结合开关电容阵列及开关电感方案,提高宽带调谐电容、电感Q值,扩展VCO工作频段,降低相位噪声.同时,输出匹配网络也采用开关电容切换方式,实现了5G毫米波双频段良好阻抗匹配及稳定功率输出.流片测试结果表明该VCO可以完整覆盖5G毫米波双频段24.25~27.5 GHz和37~43.5 GHz,低频段输出功率-4.8~0 dBm,高频段输出功率-6.4~-2.3 dBm.在24.482 GHz载频,1 MHz频偏处的相位噪声为-105.1 dBc/Hz;在43.308 GHz载频,1 MHz频偏处的相位噪声为-95.3 dBc/Hz.VCO核心直流功耗15.3~18.5 mW,电路核心面积为0.198 mm^(2).低频段(高频段)的FoM(Figure of Merit)及FoMT优值分别达到-181.3 dBc/Hz(-175.4 dBc/Hz)、-194.3 dBc/Hz(-188.3 dBc/Hz).

高牌号无取向硅钢生产流程中织构控制研究现状

在节能减排的背景之下,水电、风电和核电等清洁能源行业得到了快速发展。高牌号无取向硅钢是上述发电机组应用最普遍的铁芯材料。因此,开发低铁损和高磁感的高牌号无取向硅钢是清洁能源产业高质量发展的前提条件。织构是影响高牌号无取向硅钢磁感和铁损的主要因素之一,受到生产工艺的影响。然而,高牌号无取向硅钢工艺流程长,影响织构控制的工艺因素众多。为了满足高牌号无取向硅钢在低铁损时实现高磁感,在产品加工时应尽量避免对磁性能不利的{111}织构的形成,促进对其有利的{100}和{110}织构形成。本文首先介绍了高牌号无取向硅钢的工艺流程,对比了国内外钢铁企业产品的磁性能(P_(15/50)和B_(50))。其次,阐述了高牌号无取向硅钢在炼钢、热轧、常化、冷轧和成品退火过程中促进有利织构形成的影响因素。最后,归纳出能促进高牌号无取向硅钢有利织构形成的生产工艺,并对织构控制的发展方向提出了建议。

藏品保存环境中的硅胶型被动调湿材料吸放湿模型研究进展

综述了几种常见的硅胶型被动调湿材料吸/放湿模型,包括湿度半衰期模型、集总参数模型、硅胶颗粒扩散模型、多孔材料扩散模型、硅胶床层扩散模型、温度耦合扩散模型等;结合博物馆藏品保存环境的特点和需求,对不同吸/放湿模型的适用性进行了分析,比较了各模型在博物馆湿度控制应用场景中的优势和局限性。指出被动调湿材料和藏品保存环境相关参数的准确测定对吸/放湿模型的应用效果非常重要,并提出有必要继续开展被动调湿材料吸/放湿模型精准性、使用操作便利性等方面的研究。

基于统计过程控制的硅转接板良率优化系统设计

针对2.5D封装用硅通孔(through silicon via,TSV)硅转接基板批量化生产过程中缺乏可靠性评价与优化技术的问题,提出基于统计过程控制(statistical process control,SPC)的评估控制系统,实现在线工艺状态监控及评价,设计硅转接板测试用工艺控制检测(process control monitor,PCM)结构,阐述自动光学检测(automated optical inspection,AOI)中常见的缺陷对系统可靠性的影响。提出的SPC系统对硅转接板批量化生产良率提升具有重要意义。

闪光焊机硅钢焊接时影响焊缝稳定性因素分析

针对酒钢碳钢冷轧的闪光焊机在开发无取向硅钢50JW800存在焊接后焊缝稳定性差,频繁断带原因进行了分析。以酒钢碳钢薄板厂2022年1月发生的多起硅钢焊缝断带事件为攻关对象,通过大量实测数据统计分析,总结出硅钢生产时焊缝断带原因,并提出影响焊缝稳定性的因素及控制措施,为闪光焊机生产硅钢过程中稳定焊缝质量,保障生产顺行提供了有效指导。

220-1000kV电力变压器用取向硅钢质量评估

对2020-2023年期间国家电网公司新建和扩建的220~1000kV变电站工程中电力变压器/电抗器用取向硅钢进行了质量监督与评价,共涉及175项变电站工程、24家变压器制造企业、3家取向硅钢生产企业。基于取向硅钢产品技术条件与测试方法标准,抽检了包括20QH070、23QH075、27QH085、30QH100等23个牌号在内的累计超20000片取向硅钢样品。结果表明,性能不合格率呈逐年下降趋势。并指出了批次供货取向硅钢产品在磁性能、涂层性能、外观质量上存在的问题。通过持续开展新入网取向硅钢质量评估,为加强电力变压器质量源头管控,助力打造本质安全电网提供了有力支撑。

汉钢1号高炉超低硅高炉稳顺生产实践

2023年在钢铁市场形势持续低迷形势下,系统降本压力巨大,为了进一步降低铁前成本,汉钢1号高炉实施超低硅冶炼生产实践,以高炉操作管理为核心,通过加强原燃料管理、提高炉渣碱度、制定合理操作方针、稳定炉况、加强设备维护保障等措施实现低硅不低热,降硅不降质铁水含硅量是评价高炉铁水质量和生产技术水平的重要指标,2023年7—11月份实现生铁平均w[Si]=0.27%,w[S]=0.035%,同时实现高炉持续稳定顺行,取得了良好的经济效益,为公司降本增效作出突出的贡献。

基于ASM E2000外延炉温控系统的电压校准研究

ASM E2000外延炉采用可控硅(SCR)来控制加热灯管的输入电压,采用热电偶(TC)监测并反馈温度的方式进行加热。该机型的加热系统中,各项电压的校准精度决定了系统控制的温度精度。研究的温控系统可分为TC电路板和SCR电路板,对于TC信号处理板的电压校准,其校准精度应在±0.01 V;对于SCR控制信号的电压校准,其校准精度应在±0.001 V;对于SCR输出的电压校准,应优先测量进电电压,根据负载和进电电压的具体情况做出调整,其校准精度应在±1 V。这样的校准方法可以有效、精准地控制生长温度,并使机台间的差异性达到最小,提升机台的标准化能力。

硅片磨床伺服进给系统仿真模型与分析

在硅片磨削时,硅片加工质量与硅片磨床的进给系统性能密切相关。为了提升硅片磨床进给系统的精度和稳定性,提出了采用上位机、运动控制卡、伺服驱动器、位置传感器进行闭环控制进给的技术方案。研究了伺服系统和机械系统两者之间的相互耦合关系,建立了动力学模型,搭建了基于PID控制的三闭环控制系统,采用MATLAB中Simulink模块对进给系统进行仿真分析。仿真结果表明,磨床进给系统速度波动量在1%以下满足硅片磨削对进给精度的要求。