一种提高硅集成电感Q值的方法

设计和制作了硅集成电感，采用常规的硅工艺，在衬底形成间隔的pn结隔离来减少硅衬底的涡流损耗。实验测量了硅集成电感的S参数并研究了衬底结隔离对硅集成电路的电感量和品质因素（Q）的影响。结果表明一定深度的衬底结隔离能有效地使电感Q值提高40％。     

多孔硅衬底在RFIC无源器件中的应用

介绍低阻硅基多孔硅作为低损耗衬底在射频集成电路（RFIC）无源器件上的应用，分别讨论了在RFIC中的传输线，移相器和电感等无源器件运用多孔硅衬底后性能和主要参数的改良变化，并从理论上分析变化的原因。多孔硅衬底大大降低了RFIC电路中传输线的损耗，使移相器的工作频率和相移量都发生变化。运用多孔硅衬底，回旋电感的最高Q增加了63％（16．8～27．4），最高响应频率增加了28％（15．2～19．4GHz）。结果表明多孔硅衬底在高频情况下完全能满足RFIC元件的要求。     

时域有限差分算法与遗传算法在平面螺旋电感设计中的应用

文章通过电磁场时域有限差分(FDTD)算法与遗传算法(GA)相结合进行平面螺旋电感设计。通过优化单元网格大小，可优化设计整个平面螺旋电感（包含空气桥）的结构尺寸。介绍了该方法既能够进行严格的电磁场求解，又可以避免繁杂的实验过程，是优化设计的一种有效而准确的手段。     

掩膜法制备薄膜电感

采用掩膜方法制备了栅极型薄膜电感，并测试了这些薄膜电感的电感值和品质因数（Q值）在100MHz-10GHz范围的频谱特性。在此频率范围内，两种样品的电感值显示了平稳的频率特性，其数值分别为130nH,155nH；电阻在6GHz以下也保持平稳，分别为31Ω，51Ω，在这个频率以上，由于高频趋肤效应而有一定的增大；Q值在1-6GHz之间在20以上，并且在6GHz附近分别达到最大值160和110。在100MHz-10GHz范围内，这些电学参量的频谱特性符合实际应用的需要。     

基于FIB—SID技术的三维金属无源电感制备与测试

重点研究了聚焦离子束的相关原理和应用。利用聚焦离子束应力引入致形变（Focused Ion Beam Stress-Introduced De-formation, FIB-SID）技术与常规微加工工艺相结合,制备微型金属无源螺旋电感的设计方法和工艺流程,并对其电学性能进行初步高频测试。首先在SOI（ Silicon-on-Insulator ）基片上通过光刻、溅射以及各项同性刻蚀等常规工艺制得悬浮的金属悬臂梁,再利用FIB刻蚀原理进行应力引入,通过控制注入离子剂量、FIB应力引入的次数、FIB扫描的间距等试验参数制得不同尺寸结构的三维螺旋金属无源电感。最后,采用安捷伦网络分析仪与微波探针台,使用GSG结构及相应的去嵌方法,对微型金属螺线管电感进行了高频测试。得出了三维螺旋微纳电感的电感值、品质因子、电压驻波比、回波损耗随频率变化关系。     

不锈钢衬底上沉积类金刚石薄膜的硬度

利用射频辉光放电法在不锈钢衬底上制备了类金刚石薄膜，用显微硬度计测试了薄膜与衬底复合膜度和衬底硬度。并用Ｂ．Ｊｏｎｓｏｎ和Ｂ．Ｈｏｇｍａｒｋ方法将薄硬度分离出来，得到了硬度值与制与制备参数间的关系，确定了在不锈钢衬底上沉积高度和强附丰度类金刚石薄膜的最佳工艺条件范围，并对实验结果进行了理论解释。     

WC和Si衬底生长金刚石薄膜的研究

采用ＳＥＭ,Ｒａｍａｎ光谱等手段,较全面系统地研究了ＨＦＣＶＤ法在ＷＣ和Ｓｉ衬底上生长金刚石薄膜时,衬底预处理、碳源深度、热丝及衬底温度等对金刚石形核、生长的影响。并对两种衬底进行了对比与分析,最后总结出影响金刚石形核密度、形核速率、晶形结构及晶形完善性的关键因素。     

影响金刚石薄膜生长因素的研究

本文用ＨＦＣＶＤ法对在硬质合金衬底上生长金刚石薄膜的诸多影响因素，如衬底的预处理、碳源浓度和热丝及衬底温度等进行了系统地研究并最终找出在该衬底上生长金刚石薄膜的最佳生长条件。     

柔性衬底氧化物半导体透明导电膜的研究进展

回顾和评述了柔性衬底氧化物透明导电膜（包括锡掺杂的三氧化二铟ITO薄膜、铝掺杂的氧化锌AZO薄膜等）的研究进展情况。报道了在柔性衬底上制备的ITO膜、ZnO膜的光电性质对衬底种类、制备工芑及制备参数的依赖关系，给出了在此领域内应进一步进行的工作。     

平面天线结构对电场强度分布的影响

建立电感耦合等离子体源（ＩＣＰＳ）平面天线的电磁场模型，并进行模拟计算。计算结果表明，天线环数较多时，电场强度分布较均匀，基片上离子流密度分布较均匀。若由平面形改为螺旋帽形，能改善电场强度分布，从而改善基片上离子流密度分布的均匀性。还讨论了天线结构对电场强度的影响。     

Propagation of longitudinal leaky surface waves under periodic SiO (2)/Al structure on Li(2)B(4)O(7) substrate

The properties of longitudinal leaky surface waves (LLSW) under a periodic SiO(2)/Al structure on Li(2)B(4)O (7) (LBO) substrate, were investigated theoretically and experimentally, in order to improve the high propagation losses of LLSWs under a periodic Al grating with the normalized thickness over 2%. In the theoretical analysis, the previously presented method based on the boundary integral equations for the periodic metal grating structure on the substrate was extended to include the dielectric layer. In the experiments, devices with Al electrodes recessed into a SiO(2) groove on LBO were fabricated, and the propagation losses of them were estimated. As a result, it was shown that, when the surface of the structure was flattened, the propagation losses were sufficiently low and the first Bragg stopband width decreased.     

Experimental investigation of acoustic substrate losses in 1850-MHz thin film BAW resonators

After optimizing for electromechanical coupling coefficient K², the main performance improvement in the thin film bulk acoustic wave resonators and filters can be achieved by improving the Q value, i.e., minimizing the losses. In Braggreflector- based solidly mounted resonator technology, a significant improvement of Q has been achieved by optimizing the reflector not only for longitudinal wave, the intended operation mode, but also for shear waves. We have investigated the remaining acoustic radiation losses to the substrate in so-optimized 1850-MHz AlN resonators by removing the substrate underneath the resonators and comparing the devices with and without substrate by electrical characterization before and after the substrate removal. Several methods to extract Q-values of the resonators are compared. Changes caused by substrate removal are observed in resonator behavior, but no significant improvement in Q-values can be confirmed. Loss mechanisms other than substrate leakage are concluded to dominate the resonator Q-value. Difficulties of detecting small changes in the Q-values of the resonators are also discussed.     

Development of a generalized model for analyzing phase characteristics of SAW devices under mass and fluid loading

vA generalized model that integrates the Navier-Stokes equation and coupling-of-modes (COM) model for biosensing SAW devices is developed in this paper. The SAW device is separated into three regions: interdigital transducer (IDT), substrate (delay line), and sensing regions. To evaluate the effects of metal thickness, mass loading caused by bioreaction, and different viscous fluid loading, the sensing region is further divided into three layers: piezoelectric substrate, metal layer, and fluid layer. In contrast to the conventional study, which is focused on the change of phase velocity, this model can evaluate the insertion loss and phase shifts under different sensing conditions. It can be shown that the integration of the COM model can provide guidelines for designing the bio-sensing device such as choosing the proper number of IDT, the width of the overlap, and the thickness of the metal layer. Furthermore, the generalized model can be utilized to evaluate the optimal thickness of the metal layer to achieve the maximum sensitivity.     

A New Type of Q Meter Using Variable-Width Pulse Excitation

There are several well-known methods of measuring the Q of a resonant circuit, each with its limitations. Errors are introduced into measurements of high-Q values due to loading effects and radiation losses. A theoretical basis for the development of a Q meter which will not load a high-Q resonant circuit has been established. This new type of Q meter will use variable-width pulse excitation in lieu of sinusoidal excitation and will use elapsed-time Q-measurement techniques. It is seen that if the width of the exciting pulse is known, the resonant frequency of the resonant circuit can be directly determined. A Q meter using this approach will actually yield more information about a resonant circuit than can be determined using presently standard-type Q meters and will yield this information well beyond the Q and frequency capabilities of today's Q meters.     

Soft magnetic properties of nano-structure-controlled magneticmaterials

The soft magnetic properties of Nano-Structure-Controlled NANOCON magnetic materials have been studied, The NANOCON materials consist of Fe-based soft magnetic metal particles which are separated from each other by insulation layers of metal oxides on the order of 10-nm thick, The permeability of NANOCON materials was constant up to 10 MHz due to the small isolated particles size compared with skin depth. The value of quality factor (Q) and the peak frequency of Q could be adjusted by the particle size of NANOCON materials due to the minimization of eddy current losses due to the particle isolation     

Similarities of stress concentrations in contact at round punches and fatigue at notches: implications to fretting fatigue crack initiation

A linear elastic model of the stress concentration due to contact between a rounded flat punch and a homogeneous substrate is presented, with the aim of investigating fretting fatigue crack initiation in contacting parts of vibrating structures including turbine engines. The asymptotic forms for the stress fields in the vicinity of a rounded punch-on-flat substrate are derived for both normal and tangential loading, using both analytical and finite element methods. Under the action of the normal load, P , the ensuing contact is of width 2 b which includes an initial flat part of width 2 a . The asymptotic stress fields for the sharply rounded flat punch contact have certain similarities with the asymptotic stress fields around the tip of a blunt crack. The analysis showed that the maximum tensile stress, which occurs at the contact boundary due to tangential load Q , is proportional to a mode II stress intensity factor of a sharp punch divided by the square root of the additional contact length due to the roundness of the punch, Q /(√( b − a )√ π b ). The fretting fatigue crack initiation can then be investigated by relating the maximum tensile stress with the fatigue endurance stress. The result is analogous to that of Barsom and McNicol where the notched fatigue endurance stress was correlated with the stress intensity factor and the square root of the notch-tip radius. The proposed methodology establishes a 'notch analogue' by making a connection between fretting fatigue at a rounded punch/flat contact and crack initiation at a notch tip and uses fracture mechanics concepts. Conditions of validity of the present model are established both to avoid yielding and to account for the finite thickness of the substrate. The predictions of the model are compared with fretting fatigue experiments on Ti–6Al–4V and shown to be in good agreement.     

无源压力传感器Q值对信号传输性能的影响(英文)

为了解决无源压力传感器的无线信号传输性能问题,采用环氧树脂基底制作无源压力传感器模拟结构.传感器无线测试装置由共振电容空腔和感应天线组成,内部无需有源器件、电池等.通过改变压力敏感结构电感天线的金属层厚度和线宽等因素来研究无线信号传输性能.经过实验测试,电感的品质因素Q影响传感器的信号传输.可以通过对金属层加厚,对线宽加宽,达到减小电感的电阻,从而增大传感器电感的Q值,即有利于无线信号的传输.     

Calculation of the damping factors for slot and microstrip lines based on ferroelectric film-dielectric substrate structures

The factor of damping related to a finite conductivity of metal electrodes and losses in a ferroelectric film is calculated for slot and microstrip lines based on ferroelectric film-dielectric substrate structures.     

冷金属过渡条件下AZ61镁合金在两种钢板上的润湿行为

采用动态座滴法研究冷金属过渡条件下,AZ61镁合金分别在Q235钢板和镀锌钢板表面的润湿行为及其界面微观结构。结果表明:润湿行为与焊接工艺参数中的送丝速率密切相关;无论基板采用镀锌钢还是Q235钢在界面处均观察到Al-Fe金属间化合物层,其形成符合热力学形成条件;在Q235钢表面润湿时,送丝速率增加,界面反应变得剧烈,因而润湿性变好,在镀锌钢表面润湿时,送丝速率增加,加剧锌的挥发,使裸露的表面显金属性,因而润湿性变好;当送丝速率≤10.5m·min~(-1)时,镁在Q235钢板上的润湿性要好于镀锌钢板,且后者锌的挥发将导致工艺不稳定。     

Micromachined acoustic wave resonator isolated from substrate

This paper describes high Q, free-standing, narrow beam supported film bulk acoustic-wave resonators (FBARs) fabricated with silicon micromachining. The resonators are composed of metal/ZnO/metal/Si(x)Ny (or metal/ZnO/metal) composite layers, which are suspended by narrow Si(x)Ny/metal (or metal) beams to minimize energy leakage to the substrate. A layer of 0.5-microm thick parylene deposited and patterned over the Si(x)Ny/metal (or metal) beams is proven to enhance the sturdiness of the free-standing structure greatly. The highest Q (quality) factors we have obtained with this new structure are 1,587 and 769 at 2.7 and 5.1 GHz, respectively. This paper also describes the effect of removing the silicon-nitride support layer (to form air-backed FBARs that do not use any supporting layer below or above piezoelectric the ZnO layer sandwiched by two metal layers). The electromechanical coupling constant (Kt2) is improved from 3.2% to 6.8% when a 0.9-microm thick silicon-nitride support layer is removed.