MOPCVD硬膜技术研究

在ＭＯＰＣＶＤ－Ｔｉ（ＣＮ）膜的沉积过程中,沉积温度是一个重要工艺参数,当沉积温度低时,虽然沉积速率高但膜的硬度低,而当沉积温度高于一定值后,碳化了的金属有机化合物阻止膜的继续生长,由于ＭＯＰＣＶＤ－Ｔｉ（ＣＮ）膜是由Ｔｉ（ＣＮ）是一些有机化合物碎片组成,膜的硬度也低于用于ＰＣＶＤ法制备的Ｔｉ（ＣＮ）膜,所以用ＭＯＰＣＶＤ法制备的Ｔｉ（ＣＮ）膜只能属于一种类Ｔｉ（ＣＮ）膜。     

纳米碳管对MWPCVD过程增强金刚石形核的影响

利用石英钟罩式微波等离子体化学气相沉积（ＭＷＰＣＶＤ）实验装置,研究了硅基体表面沉积金刚石薄膜时纳米碳管对金刚石形核过程的影响。扫描电子显微镜（ＳＥＭ）形貌分析结果显示,纳米碳管处理能够促进金刚石形核。对非研磨基体而言,这是一种有效的增强金刚石形核的表面预处理方式。     

类金刚石碳膜的硬度测定方法研究

研究了有衬底影响的类金刚石碳（ＤＬＣ）膜硬度测定技术。采用Ｈ－Ｄ关系外推、Ｍｅｙｅｒ图计算及Ｊ¨ｏｎｓｓｏｎ－Ｈｏｇｍａｒｋ公式计算（考虑ＩＳＥ）等三种方法测定了ＤＬＣ膜的“真实”硬度。结果表明，由Ｍｅｙｅｒ图计算的薄膜硬度最可靠、简便。通过试验还发现ＤＬＣ膜有约１５％的弹性恢复，并认为ＤＬＣ膜的硬度测定采用克努普压头更为恰当。     

基于MMS的可编程序控制器入网研究与实现

本文首先对ＭＡＰ３．０应用层的ＭＭＳ协议作了基本介绍，侧重于ＶＭＤ模型的描述。在简单介绍可编程序控制器（ＰＣ）后，对ＰＣ入网策略作了研究，以较在篇幅叙述了ＰＣ／ＰＣ功能到ＶＭＤ模型的映射，并给出以这种策略为指导的实现例子。最后对ＰＣ入网作了总结和展望。     

激光—等离子体辅助化学气相沉积工艺参数对氮化硅膜显微硬度的影响

采用一种新的方法－激光－等离子体辅助气相沉积法，在自行研制的ＬＰＣＶＤ装置上进行了Ｓｉｈ４－ＮＨ３－Ｎ２体系沉积Ｓｉ３Ｎ４膜的工艺试验；采用正交试验法选择工艺参数，根据显微硬度评价膜层性能，并找出最佳工艺参数；激光功率密度为３２８Ｗ／ｃｍ＾２，ＲＦ电源功率为５０Ｗ，氮硅流量比为１０。结果表明，激光功率密度对膜层显微硬度的影响最大，ＲＦ电源功率的影响次之，氮硅流量比的影响最弱。     

多功能压阻式压力传感器的改进

本文提出了一种改进包括一个测量范围为１０ｋＰａ的差压传感器，一个测量范围为６ＭＰａ的静压传感器和一个用于智能差压变送器的温度传感器的压阻式多功能传感器性能的方法。可以使静压传感器的输出大于２５ｍＶ／Ｖ／６ＭＰａ，并且将差压对静压传感器的影响减小到小于０．３５ｍＶ／Ｖ／１０ｋＰａ，     

石英钟罩式MPCVD制备金刚石薄膜

利用自行研制的新型石英钟罩式微波等离子体化学气相沉积（ＭＰＣＶＤ）装置进行轩金刚石薄膜的实验研究。用扫描电子显微镜（ＳＥＭ）对形貌观察和喇曼谱测试表明，由此装置可以面积较大、晶体良好、杂质少、比较纯净的高质量金刚石薄膜。     

CVD金刚石厚膜刀具的耐磨性试验

介绍了ＣＶＤ 金刚石刀具的特点,进行了ＣＶＤ 金刚石厚膜刀具与ＰＣＤ 刀具的耐磨性对比试验,结果表明ＣＶＤ 金刚石厚膜刀具的耐磨性明显优于ＰＣＤ 刀具,但韧性略低。     

PREDICTION OF PUMP CHARACTERISTICS ACCORDING TO GEOMETRICAL PARAMETERS OF IMPELLER AND VOLUTE CASING

ＰＲＥＤＩＣＴＩＯＮＯＦＰＵＭＰＣＨＡＲＡＣＴＥＲＩＳＴＩＣＳＡＣＣＯＲＤＩＮＧＴＯＧＥＯＭＥＴＲＩＣＡＬＰＡＲＡＭＥＴＥＲＳＯＦＩＭＰＥＬＬＥＲＡＮＤＶＯＬＵＴＥＣＡＳＩＮＧＰＲＥＤＩＣＴＩＯＮＯＦＰＵＭＰＣＨＡＲＡＣＴＥＲＩＳＴＩＣＳＡＣＣＯＲＤ...     

气相沉积TiN和Ti（C,N）镀层的抗氧化性能

研究了气相沉积ＴｉＮ和Ｔｉ（Ｃ，Ｎ）镀层的抗氧化性能，通过ＳＥＭ观察和ＸＲＤ相分析，研究分析了氧化腐蚀产物类型，探讨了膜基体系失效机制。结果表明，气相沉积层的抗氧化性能明显优于无镀层的３Ｃｒ２Ｗ８Ｖ试样，尤以ＰＣＶＤ ＴｉＮ性能最佳，氧化产物为金红石型ＴｉＯ２。     

The tribological properties of YBa2Cu3O7 films in ambient environment

In the present study, high-T_c superconducting thin YBa₂Cu₃O₇ films and polysilicon films were prepared to investigate the initial sliding friction properties using a ball-on-flat tribometer when samples were moved against a sapphire ball or a steel ball in ambient environment. The surface topography was measured with atomic force microscope (AFM). After five times testing, the experimental results indicate that the friction coefficient of YBa₂Cu₃O₇ films is lower than that of polysilicon films when sliding against a sapphire ball and almost the same when sliding against a steel ball. In particular, the initial friction of YBa₂Cu₃O₇ films is more stable when sliding against a sapphire ball. However, the initial friction of polysilicon films fluctuates during a cycle period when sliding against a sapphire ball. They are both stable when sliding against a steel ball. Although, the surface profile of the YBa₂Cu₃O₇ film is rough and can be seen to be rougher than the polysilicon film, but the friction coefficient of the YBa₂Cu₃O₇ film is lower than that of polysilicon film. Also, although the topography of YBa₂Cu₃O₇ films changes during friction, the friction coefficients are stable. This clearly shows that the initial sliding friction of YBa₂Cu₃O₇ films under microfriction is stable. The observation signifies YBCO film is a good film to prevent stick–slip motion in ambient environment. The wear properties of YBa₂Cu₃O₇ films suggest that the superconducting outgrowths (CuO) are loose and they can be easily removed.     

低压化学气相淀积多晶硅薄膜工艺研究

在研制器件过程中，多晶硅制备的工艺条件对其性能影响较大。讨论了低压化学气相淀积（LPCVD）关键材料多晶硅薄膜的基本原理，考察了工作压力、反应温度等对多晶硅薄膜淀积速率的影响，以及影响多晶硅薄膜质量的因素，提出了改进措施，优化了多晶硅制备工艺参数，制备了合格的多晶硅薄膜。     

阀门用波纹管爆破压力的有限元分析

作为阀门外密封元件的波纹管是影响阀门外密封性能的关键部件,掌握工作状态下的应力状况非常重要.基于有限元方法建立了阀门用波纹管的爆破压力分析方法,同时采用有限元计算和试验相结合的方法.分析了波纹管的爆破压力.研究结果表明,波纹管的爆破压力值为61.4MPa,有限元计算结果为59.44 MPa,二者数值和位置都基本吻合.波...     

Determination of tensile properties and residual stresses of Ni-Co thin films

This paper reports tensile properties and residual stresses of Ni-Co thin films. To measure elastic (and plastic) properties, direct tensile tests using dog-bone type specimens are performed first. Assuming that residual stresses vary linearly through the film thickness, bending and membrane residual stress components are measured using cantilever beam and T-structure beam specimens, respectively. Averaged values of Young’s modulus, yield strength and tensile strength are found to be about 163GPa, 1,700MPa and 2,000MPa, respectively. The membrane and bending residual stress components are found to be about 825MPa and 47MPa, respectively.     

微桥结构Ni膜杨氏模量和残余应力研究

采用MEMS(MicroelectromechanicalSystems)技术研制了镍(Ni)膜微桥结构试样,应用陶瓷压条为承力单元,与纳米压痕仪XP系统的Berkovich三棱锥压头相结合,解决了较宽Ni膜微桥加载问题。测量了微桥载荷与位移的关系,并结合微桥力学理论模型得到了Ni膜微桥的杨氏模量及残余应力,其值分别为190.5GPa和146MPa,与应用纳米压痕仪直接测得的带有Si基底的Ni膜杨氏模量186.8±7.34GPa相吻合。     

Tribology of confined Fomblin-Z perfluoropolyalkylethers: molecular weight dependence and comparison between unfunctionalized and telechelic chains

The dynamic shear properties of molecularly-thin films of unfunctionalized and end-functionalized (telechelic) Fomblin-Z perfluoropolyalkylether (PFPAE) melts with number-average molecular weight M _n≈ 3000−4000 g,mol^-1 have been studied at shear rates of 10^-2−10⁵ s^-1 at normal pressures of 1 and 3 MPa. The shear responses are compared to measurements on end-functionalized polymers of the same chemical composition but lower molecular weight, M _n≈ 2000 g,mol^-1. The predominantly elastic response and high shear moduli of the confined film of unfunctionalized polymer, Fomblin Z03, suggest that it forms a structure likely to solidify already at low pressure. Its lubricating properties are less favorable than the ones found for hydroxyl- (DOL) and piperonyl-terminated Fomblin-Z (AM2001, AM3001), where associated molecules form a structure less prone to solidification under confinement. The thickness of the compressed films of the end-functionalized polymers increased more strongly with molecular weight than as M _n ^0.5 . The shear moduli were found to be larger, the higher the molecular weight, indicating slower relaxations. At a normal pressure of 3 MPa, these films solidified and displayed stick–slip as seen already at 1 MPa in the Z03 film. The limiting shear stress of the unfunctionalized Z03, σ > 3 MPa, exceeded by an order of magnitude the limiting shear stress of all of the end-functionalized polymers. The limiting shear stress of the hydroxyl-terminated polymer was larger than that of the piperonyl-terminated polymer. This revised version was published online in August 2006 with corrections to the Cover Date.     

多晶硅纳米薄膜牺牲层压力敏感结构设计

为使多晶硅纳米薄膜良好的压阻特性在MEMS(微机电系统)压阻传感器中得到有效应用,在设计牺牲层结构压力传感器芯片中探索性地采用了多晶硅纳米薄膜作为应变电阻,并给出这种传感器的设计方法。分析了牺牲层结构弹性膜片的应力分布对传感器灵敏度的影响,优化设计了量程为0~0.2 MPa多晶硅纳米膜压力传感器芯片的结构参数。有限元法仿真结果表明:在保证传感器灵敏度大于50 mV/(MPa.V)的前提下,零点温漂系数可小于1×10-3FS/℃;灵敏度温漂(无电路补偿)可小于1×10-3FS/℃.为高灵敏、低温漂、低成本的高温压力传感器集成化发展提供了一条可行途径。     

Mechanical characterization of micro/nanoscale structures for MEMS/NEMS applications using nanoindentation techniques

Mechanical properties of micro/nanoscale structures are needed to design reliable micro/nanoelectromechanical systems (MEMS/NEMS). Micro/nanomechanical characterization of bulk materials of undoped single-crystal silicon and thin films of undoped polysilicon, SiO(2), SiC, Ni-P, and Au have been carried out. Hardness, elastic modulus and scratch resistance of these materials were measured by nanoindentation and microscratching using a nanoindenter. Fracture toughness was measured by indentation using a Vickers indenter. Bending tests were performed on the nanoscale silicon beams, microscale Ni-P and Au beams using a depth-sensing nanoindenter. It is found that the SiC film exhibits higher hardness, elastic modulus and scratch resistance as compared to other materials. In the bending tests, the nanoscale Si beams failed in a brittle manner with a flat fracture surface. The notched Ni-P beam showed linear deformation behavior followed by abrupt failure. The Au beam showed elastic-plastic deformation behavior. FEM simulation can well predict the stress distribution in the beams studied. The nanoindentation, scratch and bending tests used in this study can be satisfactorily used to evaluate the mechanical properties of micro/nanoscale structures for use in MEMS/NEMS.     

Invited Article: Simultaneous mapping of temperature and stress in microdevices using micro-Raman spectroscopy

Analysis of the Raman Stokes peak position and its shift has been frequently used to estimate either temperature or stress in microelectronics and microelectromechanical system devices. However, if both fields are evolving simultaneously, the Stokes shift represents a convolution of these effects, making it difficult to measure either quantity accurately. By using the relative independence of the Stokes linewidth to applied stress, it is possible to deconvolve the signal into an estimation of both temperature and stress. Using this property, a method is presented whereby the temperature and stress were simultaneously measured in doped polysilicon microheaters. A data collection and analysis method was developed to reduce the uncertainty in the measured stresses resulting in an accuracy of +/-40 MPa for an average applied stress of -325 MPa and temperature of 520 degrees C. Measurement results were compared to three-dimensional finite-element analysis of the microheaters and were shown to be in excellent agreement. This analysis shows that Raman spectroscopy has the potential to measure both evolving temperature and stress fields in devices using a single optical measurement.     

复合钝化多晶硅纳米膜应力分布仿真分析

多晶硅纳米薄膜具有优良的压阻特性,为提高其在传感器应用中的稳定性和可靠性,对这种薄膜的钝化层结构进行了研究.基于压力传感芯片的结构特点,建立了钝化层结构的有限元分析分析模型,给出了应力分布与SiO_2和Si_3N_4钝化层结构之间关系.结果表明:采用Si_3N_4-SiO_2-Si_3N_4复合钝化结构,适当控制各结构层厚度可有效降低热失配引起的内应力.从而给出了降低薄膜内应力的钝化方法,为多晶硅纳米薄膜在压阻式传感器上的应用提供了必要的技术支持.