单基三电极石英晶体谐振器频率-温度特性研究

设计了一种新型的单基三电极石英晶体谐振器,并在大气环境条件下测试分析了这种谐振器的频率-温度特性,验证了其频率-温度特性与已有的单基单电极谐振器的频率-温度特性基本一致,曲线为三次曲线。在相同激励及环境条件下,在同一基片上设置多对电极时,各对电极构成的谐振器的频率-温度特性基本相同。根据这种相似特点,将同一基片上不同电极对应的谐振器的振动频率进行差频补偿,可有效地抑制温度对谐振器振动频率的影响。这种谐振器所采用的差频补偿方法可为石英谐振器相关特性的进一步开发利用提供依据。研究了这种结构的石英晶体谐振器的晶片表面处理(是否抛光)及边沿形状(是否倒边)对其频率-温度特性的影响。实验结果表明,对单基多电极石英晶体谐振器的晶片表面进行抛光并对边沿进行倒边处理后,谐振器的稳定性得到了有效的改善,性能得到了优化。     

单基三电极石英晶体谐振器频率-温度特性研究

设计了一种新型的单基三电极石英晶体谐振器，并在大气环境条件下测试分析了这种谐振器的频率-温度特性，验证了其频率-温度特性与已有的单基单电极谐振器的频率-温度特性基本一致，曲线为三次曲线。在相同激励及环境条件下，在同一基片上设置多对电极时，各对电极构成的谐振器的频率-温度特性基本相同。根据这种相似特点，将同一基片上不同电极对应的谐振器的振动频率进行差频补偿，可有效地抑制温度对谐振器振动频率的影响。这种谐振器所采用的差频补偿方法可为石英谐振器相关特性的进一步开发利用提供依据。研究了这种结构的石英晶体谐振器的晶片表面处理（是否抛光）及边沿形状（是否倒边）对其频率-温度特性的影响。实验结果表明，对单基多电极石英晶体谐振器的晶片表面进行抛光并对边沿进行倒边处理后，谐振器的稳定性得到了有效的改善，性能得到了优化。     

单基三电极石英晶体谐振器频率-温度特性研究

设计了一种新型的单基三电极石英晶体谐振器,并在大气环境条件下测试分析了这种谐振器的频率-度特性,验证了其频率-度特性与已有的单基单电极谐振器的频率-温度特性基本一致,曲线为三次曲线.在相同激励及环境条件下,在同一基片上设置多对电极时,各对电极构成的谐振器的频率-温度特性基本相同.根据这种相似特点,将同一基片上不同电极对应的谐振器的振动频率进行差频补偿,可有效地抑制温度对谐振器振动频率的影响.这种谐振器所采用的差频补偿方法可为石英谐振器相关特性的进一步开发利用提供依据.研究了这种结构的石英晶体谐振器的晶片表面处理(是否抛光)及边沿形状(是否倒边)对其频率-温度特性的影响.实验结果表明,对单基多电极石英晶体谐振器的晶片表面进行抛光并对边沿进行倒边处理后,谐振器的稳定性得到了有效的改善,性能得到了优化.     

强磁场对石英谐振器的影响

基于磁-弹性耦合理论以及预应力模态分析理论,结合实验方法解释石英晶体谐振器在强磁场影响下频率变化的原因.结果表明,石英晶体谐振器的磁性支架在受到磁场的影响产生相应的应力沿石英晶片的边缘作用于石英晶体导致其谐振频率发生变化.该结果对如何减小磁场对石英晶体谐振器的影响有一定的参考价值.     

基于能陷理论的石英力敏谐振器集群的设计

石英谐振器可以作为传感器的敏感元件。为了减小温度等因素的干扰,提高石英晶体谐振器力敏特性,通过能陷理论及其厚度剪切石英晶体谐振能量分布曲线的计算,在同一圆形晶片上设计了多电极力敏谐振器集群。根据共模抑制原理,将谐振器集群输出频率信号作差频处理,以此抑制温度等因素的干扰,再将差频信号叠加以提高石英晶体谐振器集群整体力敏特性。实验结果表明,石英谐振器集群差频输出的温频特性明显优于传统的单电极谐振器,石英晶体谐振器集群整体力灵敏度系数提高到9 992 Hz/N。     

晶片研磨与腐蚀对老化影响的探讨

石英谐振器在贮存、使用过程中频率随时间变化的现象称为老化。老化的特性直接影响晶体频率的稳定性,它是石英谐振器的一个重要参数。随着科技的发展,人们对石英振谐振器频率的稳定性要求越来越高,频率年老化率也由原来的百万分之五提高到百万分之三。老化现象无法彻底消除,但可通过某些方法来减少其影响。该文通过晶片研磨、腐蚀清洗这两道工序对晶体老化的产生和消除进行分析和研究,取得了较好的效果。     

E2PROM失效故障分析

在计算机的使用中,发现E2PROM芯片出现数据丢失问题,导致计算机无法正常工作。通过对E2PROM的失效分析,其结果表明,故障的原因是芯片失效所致。经试验验证分析,确定该E2PROM器件存在芯片某流片生产批次工艺参数RRPOLY较差,影响上电复位电路的工作状态,造成部分芯片在上电过程中出现数据丢失问题。另外在E²PROM筛选中添加了非易失性测试,发现并解决了E²PROM早期失效问题。验证试验表明该措施的有效性和可行性。     

光电耦合器（OCEP）早期故障的可靠性研究及应用

通过对大量失效光耦分析研究,失效现象集中在早期,问题统一。结合光耦失效样品的失效现象、失效原理、及失效机理分析,从金线绑定异常、内部残留金属异物、漏打胶、晶片污染方面研究光耦的可靠性,发现主要失效是早期产品加工存在异常缺陷导致,产品在投入使用后短期内反馈异常。通过对制程的优化改进,如提升自动化制造、检测能力,不断优化改进制程,提升光耦制造流程可靠性,保证产品可靠性。     

一种小型压控恒温晶体振荡器的设计

简要介绍了一种小型的恒温晶体振荡器,通过对振荡参数的反复试验、修改,提高了振荡器的频率稳定度。提出一种新的设计理念,利用晶体谐振器与电感随温度变化对晶体振荡器频率所产生的不同影响,合理安排晶体振荡器内部的热场,调整晶体谐振器、热敏电阻及振荡参数的热平衡关系,在去掉恒温槽的情况下提高了温度频率特性,且大大缩小了晶体振荡器的体积。     

斜梁结构高温度稳定性MEMS自由梁谐振器设计

针对表面微加工MEMS谐振器由于温度改变引起的电气失效问题,采用一种高温度稳定性的斜梁支撑结构将温度变化引起的谐振器形变转化为水平位移,有效地避免了谐振梁与电极之间因材料热胀冷缩引起的电气失效和动态阻抗变化。在温度升高100°C的情况下,直梁支撑结构在垂直电极方向的位移为0.153μm,而文中所提出的斜梁支撑结构的位移为0.017μm;在提高温度稳定性的同时降低了由于电极间隙增大引起的谐振器动态阻抗变化,在0.3μm的初始间隙下,斜梁支撑结构的谐振器在温度升高100°C时的动态阻抗为直梁支撑谐振器的24%,损耗为-52dB,相比于传统直梁支撑结构的-61dB改善了9dB,有效地提升了MEMS谐振器的温度稳定性。     

1056 MHz反台晶体温补振荡器

介绍应用离子束刻蚀技术制作的三次泛音264 MHz反台晶体谐振器,制作1 056 MHz的温补晶体振荡器。由于晶体致薄技术的改进,突破了传统工艺晶体频率的上限,而晶体频率的提高,进一步改善了晶振的性能、体积、功耗等,简化了电路。     

Investigation of the noise characteristics of oscillators based on composite acoustic resonators

It is shown that composite acoustic resonators are promising microwave frequency-control components. It is found that, for a detuning from a carrier frequency exceeding 1 kHz, the phase noise of an oscillator stabilized by a composite resonator is lower than that of oscillators with surface-acoustic-wave crystal resonators and with AT-cut crystal resonators.     

角锥棱镜腔Cr4+:YAG被动调Q内腔式光参量振荡器

通过对角锥棱镜腔实现KTPⅡ类非临界相位匹配光参量振荡的理论分析,发现腔内存在特殊偏振方位角的本征模式,其满足Ⅱ类非临界相位匹配条件。实验上不但实现了该腔的Cr4 ∶YAG被动调Q内腔式光参量振荡器(OPO)运转,而且得到了优于平-平腔的转换效率,改善了信号光的稳定性。分析了Cr4 ∶YAG初始透过率和腔内功率密度的关系,实验获得不同Cr4 ∶YAG初始透过率、抽运能量和信号光能量的关系曲线。通过腔内功率密度的优化,电光效率高达0.25%,设计出结构紧凑、小型高效的工程实用光参量振荡器器件,抽运能量阈值为4.7 J,输出能量为11.8 mJ,脉宽为6.9 ns,发散角为7 mrad,能量稳定性为5%。     

晶体振荡器频率漂移失效分析

通过对某型晶体振荡器失效模式进行分析,结合密封性检查、扫描电子显微镜检查和能谱分析等失效分析试验结果,对该晶体振荡器频率漂移的失效机理进行研究。发现器件密封性不良是导致器件失效的根本原因,并对器件密封性工艺的优化提出建议。     

Silicon Resonator Based 3.2 $mu$W Real Time Clock With $pm$10 ppm Frequency Accuracy

This paper presents an ultra-low power generic compensation scheme that is used to implement a real time clock based on an AlN-driven 1 MHz uncompensated silicon resonator achieving 3.2 ?W power dissipation at 1 V and ±10 ppm frequency accuracy over a 0-50°C temperature range. It relies on the combination of fractional division and frequency interpolation for coarse and fine tuning respectively. By proper calibration and application of temperature dependent corrections, any frequency below that of the uncompensated resonator can be generated yielding programmability, resonator fabrication tolerances and temperature drift compensation without requiring a PLL. To minimize the IC area, a dual oscillator temperature measurement concept based on a ring oscillator/resistor thermal sensor was implemented yielding a resolution of 0.04°C. The IC was fabricated on a 0.18 ?m 1P6M CMOS technology.     

Combination dielectric resonator, power combiner, and antenna

A rectangular dielectric resonator housed in a cutoff parallel-plate waveguide is used both as a radiating element and microwave power combiner. The resonator is excited by using tuned electrically short monopole antennas to induce a longitudinal electric operating mode. The resonator is then used in conjunction with free-running oscillators in order to provide, via mutual injection locking, stable in-phase power combining. Furthermore, the resonator is arranged such that one of its faces radiates a portion of the power-combined signal. Since the resonator is housed in a cutoff waveguide, the cross-polarization radiation from the antenna is suppressed. It was found that, for a single element, a gain in the azimuthal plane of 5 dB could be achieved and, for a two-element array, a gain of 7 dB was obtained with better than -25-dB cross polarization for each case. The oscillator power-combining efficiency for a single-element antenna (two oscillators) was 91%, and the spatial power-combining efficiency for a two-element antenna array, (four oscillators) was found to be 90%. In addition, it is shown that the presence of the dielectric inserts in conjunction with coupled oscillator dynamics provides moderate overall oscillator phase noise improvement     

RF oscillator implementation using integrated CMOS surface acoustic wave resonators

This work is a proof of concept that a monolithic CMOS surface acoustic wave (SAW) resonator can function as an RF oscillator. The design of the oscillator includes the measurement characteristics of the CMOS SAW resonator, its matching networks, and RF amplifier is described. The integrated SAW resonator, with its operating frequency controlled by the spacing of its transducers was fabricated using a combination of CMOS plus post-CMOS processes. Based on the operation and performance of the SAW resonators, an equivalent circuit model of the CMOS SAW resonator was developed. A series resonant oscillator design was simulated using Microwave Office^TM. The designed matching network improves both the insertion losses and the phase slope of the resonator, while the RF amplifier provides sufficient gain to ensure oscillation. Measurements conducted on the RF-CMOS SAW oscillator demonstrated oscillation at 600 MHz.     

Stabilisation of a W-band microstrip oscillator by a dielectric resonator

The effect of temperature on the performance of a dielectric resonator compensated W-band impatt diode microstrip oscillator is shown to be quite small. The frequency change was about 2 MHz/°C as compared to the uncompensated oscillator's 10 MHz/°C. The design of the oscillator is presented and the resonator used was a cuboid of temperature compensated barium nonatitanate.