具有表面微机械结构的体声波复合谐振器研究

本文报道了一种具有表面微机械结构的新型体声波复合谐振器。讨论了ＺｎＯ薄膜换能器的取向与体波模式机电耦合系数之间的关系；复合谐振器特性与器件参数的关系。给出了谐振器的制作工艺及测试结果。器件的尺寸为２５０μｍ×２５０μｍ，谐振频率在５５９．０５ＭＨｚ。     

氧化锌薄膜体声波谐振器的研制

介绍了一种薄膜体声波谐振器和它的制备流程.该谐振器采用氧化锌压电薄膜作为压电材料,通过从硅片背部体刻蚀硅衬底的方法得到谐振器的支持层.为了避免残余应力引起的支持层起皱现象,采用氮化硅/二氧化硅/氮化硅复合膜作为支持层.采用直流磁控溅射的方法制备氧化锌压电薄膜,X射线衍射结果显示,氧化锌压电薄膜C轴择优取向明显,衍射峰半高宽为0.227 3°,显示出较好的结晶质量;扫描电镜观察到氧化锌垂直于薄膜表面的柱形晶粒结构,薄膜表面平整、致密.采用HP8753D射频网络分析仪对该薄膜体声波谐振器样品进行了测试,结果表明,谐振器具有明显的厚度伸缩振动模式,其基频在750 MHz左右,二次谐频在1.5 GHz左右.进一步提高氧化锌压电薄膜的性能,该谐振器可用于射频振荡源和射频前端滤波器中.     

压电及其它功能器件

３压电及其它功能器件９５３２７新的压电薄膜微型谐振器─ｚｏｕＹ．ＰｒｏＩｎｔＣｏｎｆＥｌｅｃｔｒｏｎＣｏｍｐｏｎＭａｔｅｒ（ＣＨＮ），１９９２；１９９～２０１采用新的压电薄膜技术和微细加工技术，成功地试作体声波（ＢＡｗ）微型谐振器。为在多晶硅薄膜上堆...     

新支撑结构空隙型压电薄膜复合谐振器

制作基片和谐振器间留有微小空隙的压电薄膜复合谐振器时,由于谐振器的应力会造成困难,同时也会影响电特性.本文提出了利用(1)悬臂支撑结构和(2)表面支撑结构以缓解这种应力,实现制作结构简易的压电薄膜复合谐振器.采用方式(1)的实验得到谐振频率为300MHz,Q(锐度)=1200,γ(容量比)=54;采用方式(2)的实验得到谐振频率为1.77GHz,Q=300,γ=250的谐振器.文中探讨了带有微小空隙薄膜的破裂和应力,阐明了本方法的可行性.     

射频薄膜体声波谐振器的研制和分析

研制了一种采用氮化硅/二氧化硅/氮化硅复合膜作为支持薄膜的高Q薄膜体声波谐振器. 当采用单层氮化硅膜或二氧化硅膜作为谐振器的支持薄膜时,由于残余应力的作用,释放完的薄膜往往会出现褶皱的现象,极大地降低了薄膜体声波谐振器的Q值;上述复合膜结构有效地解决了这个问题. 采用直流磁控溅射法制备了氧化锌压电薄膜,X射线衍射结果表明制备的氧化锌薄膜具有很好的c轴择优取向,意味着氧化锌薄膜具有较好的压电性. S参数测试结果表明该薄膜体声波谐振器在0.4~2.6GHz的频率范围内具有3个明显的谐振模式,计算了这些谐振模式的串联谐振频率、并联谐振频率、有效机电耦合系数和Q值. 在这3个模式中,第3个谐波模式的工作频率约为2.4GHz,具有最高的Q值（约为500) ,可用来制备2.4GHz的低相噪射频振荡源.     

射频薄膜体声波谐振器的研制和分析

研制了一种采用氮化硅/二氧化硅/氮化硅复合膜作为支持薄膜的高Q薄膜体声波谐振器.当采用单层氮化硅膜或二氧化硅膜作为谐振器的支持薄膜时,由于残余应力的作用,释放完的薄膜往往会出现褶皱的现象,极大地降低了薄膜体声波谐振器的Q值;上述复合膜结构有效地解决了这个问题.采用直流磁控溅射法制备了氧化锌压电薄膜,X射线衍射结果表明制备的氧化锌薄膜具有很好的c轴择优取向,意味着氧化锌薄膜具有较好的压电性.S参数测试结果表明该薄膜体声波谐振器在0.4～2.6GHz的频率范围内具有3个明显的谐振模式,计算了这些谐振模式的串联谐振频率、并联谐振频率、有效机电耦合系数和Q值.在这3个模式中,第3个谐波模式的工作频率约为2.4GHz,具有最高的Q值(约为500),可用来制备2.4GHz的低相噪射频振荡源.     

膜片上FBAR结构的阵列式伽马辐照剂量计

设计了一种膜片上薄膜体声波谐振器(FBAR)结构的伽马辐照剂量计。采用FBAR替代传统伽马辐照检测元件来实现伽马辐照剂量检测的新方法,并提出FBAR呈阵列式分布的结构,可实现辐照剂量和分布的检测。为了对FBAR进行温度补偿,设计了由SiO2与Si3N4组成的双层复合薄膜,SiO2的温度系数为+85×10-6/℃,与具有负温度系数的压电层进行复合,减小了温漂,同时增加了膜片的强度。给出了两种不同结构的阵列式伽马辐照剂量计详细的工艺路线;可望满足阵列式、高灵敏度、微小型化伽马辐照剂量检测的需求。     

多晶硅薄膜的两步激光晶化技术

采用两步激光晶化技术获得了多晶硅薄膜，分析计算了激光晶化时薄膜中的温度分布及表面温度与激光功率密度的关系，利用计算结果并优化了激光晶化时的工艺参数，采用该技术制备了性能优良的顶栅多晶硅薄膜晶体管，测量了薄膜晶体管的转移特性与输入输出特性，从多晶硅薄膜的制备工艺上分析了提高薄膜晶体管性能的原因。     

AIN薄膜体声波谐振器性能分析

采用体硅微细加工工艺制备了背空腔型AIN薄膜体声波谐振器。研究了压电层、上电极及支撑层厚度对谐振器性能的影响。测试结果表明，谐振器所用AIN压电薄膜具有（002）择优取向，器件频率特性良好。当上电极、压电层、底电极和支持层的厚度分别为110，2600，110，200nm时，谐振频率为1．759GHz，机电耦合系数3．75％，品质因数79．5。结合Mason等效电路模型模拟分析与实验结果，分析了各层厚度对频率特性的影响机理。     

硅低温双极晶体管的优化设计与制备：II结构与电特性分析

本文在前文器件掺杂分布优化设计的基础上，实现了结构设计和工艺选择，采用多晶硅发射极技术，研制成功了７７Ｋ下高增益（ＨＦＥ可达２５０）硅双极晶体管；采用多晶硅发射区和基区重掺杂技术，获得了可与ＣＭＯＳ结构兼容，基区电阻较小的硅低温双极晶体管。     

Resolution Enhancement Technology:Integrated Process Solutions using OPC

DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system.     

Cost-effective test solutions for smart card and other integrated flash applications

From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.     

Theoretical analysis of the relationship between the Brillouin gain coefficient and the strain in the optical-fiber sensors

The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.     

An improved parallel thinning algorithm with two subiterations

The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high.     

Novel fiber-optical interferometer with miniaturized probe for in-hole measurements

Today, micro-system technology and the development of new MEMS （Micro-Electro-Mechanical Systems） are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.     

Study of waveguide coupling efficiency in hybrid silicon lasers

This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel＇s.     

Teleportation of an arbitrary unknown N-qubit entangled state under the controlling of M controllers

A new quantum protocol to teleport an arbitrary unknown N-qubit entangled state from a sender to a fixed receiver under M controllers(M < N) is proposed. The quantum resources required are M non-maximally entangled Greenberger-Home-Zeilinger (GHZ) state and N-M non-maximally entangled Einstein-Podolsky-Rosen (EPR) pairs. The sender performs N generalized Bell-state measurements on the 2N particles. Controllers take M single-particle measurement along x-axis, and the receiver needs to introduce one auxiliary two-level particle to extract quantum information probabilistically with the fidelity unit if controllers cooperate with it.     

Diode-end-pumped Nd:YVO4/LBO lasers with 4.2W continuous-wave output at 457 nm

A continuous-wave (CW) 457 nm blue laser operating at the power of 4.2 W is demonstrated by using a fiber coupled laser diode module pumped Nd: YVO4 and using LBO as the intra-cavity SHG crystal With the optimization of laser cavity and crystal parameters, the laser operates at a very high efficiency. When the pumping power is about 31 W, the output at 457nm reaches 4.2 W, and the optical to optical conversion efficiency is about 13.5% accordingly. The stability of the out putpower is better than 1.2% for 8 h continuously working.     

A rigorous proof of MIMO channel capacity’s increase with antenna number

It is well known that adding more antennas at the transmitter or at the receiver may offer larger channel capacity in the multiple-input multiple-output（MIMO） communication systems. In this letter, a simple proof is presented for the fact that the channel capacity increases with an increase in the number of receiving antennas. The proof is based on the famous capacity formula of Foschini and Gans with matrix theory.     

Call for Papers

正Wireless Body-area Networks The last decade has witnessed the convergence of three giant worlds:electronics,computer science and telecommunications.The next decade should follow this convergence in most of our activities with the generalization of sensor networks.In particular with the progress in medicine,people live longer and the aging of population will push the development of wireless personal networks