基于氧化石墨烯的ST-cut声表面波高性能湿度传感器

开发了氧化石墨烯(GO)涂覆的ST-cut石英声表面波(SAW)湿度传感器。SEM和FTIR研究发现GO表面呈现起伏褶皱状且含有亲水性基团,这有利于薄膜对水分子的吸附;还发现SAW湿度传感器的频移响应由质量负载效应提供,且高湿度下传感器频移的指数增加归因于水凝结引起的阻尼效应。该传感器具有良好的灵敏度、几乎为零的温度系数、稳定的短期重复性与长期稳定性,且成本低,为湿度传感的研究提供了较好的选择。     

Wafer-level SLID bonding for MEMS encapsulation

Hermetic packaging is often an essential requirement to enable proper functionality throughout the device＇s lifetime and ensure the optimal performance of a micro electronic mechanical system （MEMS） device. Solid-liquid interdiffusion （SLID） bonding is a novel and attractive way to encapsulate MEMS devices at a wafer level. SLID bonding utilizes a low-melting-point metal to reduce the bonding process temperature; and metallic seal rings take out less of the valuable surface area and have a lower gas permeability compared to polymer or glass- based sealing materials. In addition, ductile metals can adopt mechanical and thermo-mechanical stresses during their service lifetime, which improves their reliability. In this study, the principles of Au-Sn and Cu-Sn SLID bonding are presented, which are meant to be used for wafer-level hermetic sealing of MEMS resonators. Seal rings in 15.24 cm silicon wafers were bonded at a width of 60 gin, electroplated, and used with Au-Sn and Cu-Sn layer structures. The wafer bonding temperature varied between 300 ℃ and 350 ℃, and the bonding force was 3.5 kN under the ambient pressure, that is, it was less than 0.1 Pa. A shear test was used to compare the mechanical properties of the interconnections between both material systems, in addition, important factors pertaining to bond ring design are discussed according to their effects on the failure mechanisms. The results show that the design ofmetal structures can significantly affect the reliability of bond rings.     

一种石英晶体谐振器频率粗调机系统

设计一个基于单片机及CPLD的针对32768Hz石英谐振音叉片进行自动加工的机器,该机器用于实现对石英音叉片谐振频率及阻抗的磨削调整。分析了机器结构及磨削机理,并根据多个参考变量设计加工算法以提高加工效率与产品精度。通过一个串口通信网络实现多机器的加工数据通信以增强生产管理效能。     

击垮英舰“紫石英”号

我15岁就离开了老家江苏泰兴燕头镇,报名参军来到解放军第八兵团35军。淮海战役后,部队组织一批“知识分子”进行集训,准备大军过江后接管城市。我因为读过书,有幸被选中。     

读者论坛

<正>何处才是生态城的家最近"泡沫"流行,媒体上动辄"风能泡沫"地说着。而上期的"生态城(村)"专题也让我感到一阵凉飕飕的。我正好在天津开发区上班。那天,我在公交车上见到一个建材公司的业务员,跑到这儿来参加竞标。其实,像他这样的业务员最近常常在规划中的生态城出没。总体感     

石英晶体振荡器品质因素的近似计算

运用近似计算的方法得到了石英晶体振荡器的品质因素的表达式,它对普适性地讨论品质因素有一定的参考价值。     

内蒙古新巴尔虎左旗呼吉日廷达巴地区志留纪石英闪长岩岩石地质特征

文章通过路线地质调查、剖面测制及硅酸盐、光谱、薄片鉴定,取得了新巴尔虎左旗呼吉日廷达巴地区的志留纪石英闪长岩岩体的岩性特征、矿物组成、岩石化学特征等相关信息,并结合微量元素资料,对该套岩体岩石地质特征进行了总结。     

科技动态

<正>我国能源领域首设国家级科技进步奖国家能源局近期在北京人民大会堂向22项重大能源科技进步成果颁发2009年度国家能源科技进步奖,这是我国能源领域首次设立国家级科技进步大奖;第二批国家能源研发(实验)中心命名和国家700℃超超临界燃煤发电技术创     

0.01ms红外数字毫秒计的制作

利用100KHz石英晶体、红外线光电门及十进制计数/七段译码器二合一集成电路,制做了测量精度可达0.01ms的红外数字毫秒计.