氩氧比对ZnO薄膜特性的影响与紫外探测器的研制

利用射频磁控溅射技术在SiO2／n—Si和玻璃衬底上制备ZnO薄膜,研究了溅射气体氩氧比对薄膜特性的影响,在氩氧比为2：3下所制备的ZnO薄膜c轴择优取向相对较好,薄膜的颗粒随氩氧比的增加而增大,所制备的薄膜在可见光均具有较高的透射率,吸收边在360-380nm附近;并在以SiO。／n—Si为衬底,氩氧比为2：3,经过退火处理的ZnO薄膜上制作Ag-ZnO—Ag肖特基MSM叉指结构的紫外探测器,所制作的探测器在5V偏压下漏电流为3．3×10^-8A,在紫外波段有较高的响应度,光响应度峰值在365nm附近。     

CeO2掺杂对ZnO薄膜气敏特性的影响

ZnO薄膜进行CeO2掺杂,研究掺杂含量和热氧化对薄膜结构、表面、晶粒尺寸及气敏特性的影响.结果显示,用热蒸发制备的高纯Zn膜经500℃热氧化,获得c轴取向ZnO多晶薄膜.掺CeO2可抑制晶粒生长使颗粒细化平均粒径减小,同时改善了ZnO薄膜的体相化学计量比,Zn与O的比例从未掺杂时1∶1.28降到1∶1.191.XPS...     

钼掺杂降低TiO2氧敏薄膜最佳工作温度研究

用直流反应磁控溅射法在陶瓷基片上制备出TiO2薄膜.并进行1100℃,2h的退火处理.配置钼酸铵溶液,利用浸渍法处理TiO2薄膜若干时间.取出后,进行500℃,3h退火处理.用气敏测试箱对制备出的TiO2薄膜的氧敏特性进行试验测试,发现对氧气有很好的敏感特性,比未经此项工艺处理的TiO2薄膜的最佳工作温度降低100℃,为300℃左右,并进行SEM测试,分析其表面结构,研究气敏机理.     

微型薄膜锂离子电池正极材料LiCoO2薄膜研究

研究了应用于微型全固态薄膜锂离子电池的正极材料钴酸锂 LiCoO2薄膜材料,采用磁控溅射法来制备,对其进行400℃退火处理后,进行 XRD 分析和 SEM 分析,表明在低气压条件下制备的薄膜呈非晶态,经过退火后,形成了排列致密的晶体结构,薄膜沿（003）晶面平行于基底择优生长;循环伏安测试和恒电流充放电测试表明,未经过退火处理的 LiCoO2薄膜不具有锂离子嵌入/脱出的可逆性,而经过退火处理的 LiCoO2薄膜从第二圈开始具有较好的可逆性。制备的 LiCoO2薄膜结晶状态优良、质地紧密、与衬底薄膜紧密接触、循环性能和循环充放电性能良好,可以用于微型全固态薄膜锂离子电池。     

对靶磁控溅射制备VO_x薄膜及其退火研究

利用对靶磁控溅射法在玻璃基片上制备VOx薄膜,采用正交实验方法研究了镀膜条件对VOx薄膜电阻温度系数(TCR)的影响,得到优化的镀膜工艺参数,主要包括Ar∶O2为48∶0.4、工作压力恒定为2 Pa、基底的温度为室温27℃、溅射功率保持在180W,在此基础上,进行不同温度条件的真空退火,得到薄膜TCR在-2.5%~-4.5%范围。利用原子力显微镜(AFM)和X射线光电子能谱法(XPS)分析了退火对提高薄膜TCR的作用,并找出VOx薄膜阻值与TCR的优化组合。同时,还观察到薄膜表面形貌的变化以及退火后薄膜中VO2,V2O3,V2O5的比例变化情况,并对其机理进行解释。     

应用于转角传感器的Cu-DLC电阻体制备技术研究

采用双靶共溅的方法在陶瓷基底上制备了 Cu-DLC电阻体.该电阻体具有类金刚石镀膜的硬度,同时,因掺杂的Cu降低了类金刚石镀膜的电阻率,使其兼具耐磨性和电阻特性.文中对Cu-DLC电阻体薄膜的制备工艺进行了介绍,并对薄膜的表面形貌、膜的微观组成、力学性能以及功率对电阻率的影响展开了研究.研究结果表明,该方法制备的Cu-...     

弱C轴择优AlN薄膜晶体测温技术研究

采用中频反应磁控溅射法,使氧化铝陶瓷基片上沉积了弱C轴择优的AlN薄膜。通过真空退火的方式,研究了AlN薄膜(002)晶面衍射峰晶格参数2θ随退火温度和退火时间的变化规律。采用X射线衍射仪表征了薄膜的晶体结构。研究发现,AlN薄膜的晶格参数2θ随退火温度的升高及退火时间的累积呈单调增大趋势。利用MATLAB软件线性拟合晶格参数2θ与退火温度和退火时间得出温度判读算法公式,在400~1000℃范围内,温度判读误差可以控制在7%以内。并利用MATLAB编写了温度判读软件,实现了温度的可视化判读。     

PN结型硅基TiO_2氧传感器的特性分析

采用薄膜技术研制了一种以硅PN结结构为基底材料的TiO2氧传感器,阐述了该传感器的工作原理、结构设计、工艺流程及其特性。给出了磁控溅射工艺制备银电极及TiO2薄膜的方法,利用X射线衍射(XRD)标定了TiO2薄膜的金红石相晶体结构,通过扫描电镜(SEM)分析了薄膜的表面形貌及晶粒结构,讨论了TiO2的氧敏感机理,测试薄膜的敏感特性及响应特性。实验结果表明:硅PN结基底TiO2氧传感器具有工作温度低、低功耗、体积小、线性化好的优点。     

退火对ZnO薄膜特性的影响与紫外探测器的研制

利用射频磁控溅射技术在SiO2/n-Si和石英玻璃衬底上制备了具有C轴择优取向的ZnO薄膜,研究了退火对ZnO薄膜特性的影响,并在以SiO2/n-Si为衬底、退火温度为900℃的薄膜上制作了Ag-ZnO-Ag肖特基型和Au-ZnO-Au光电导型MSM叉指结构的紫外探测器。所制作的两种MSM紫外探测器在350 nm波长紫外光照下电流增加,在紫外波段有较高的响应度,光响应度峰值在370 nm附近。     

多孔硅残余应力的研究

利用电化学腐蚀的方法在p型单晶硅(100)衬底上制备了多孔硅薄膜。利用微拉曼光谱法分别测量了处于湿化—干燥—再湿化3个阶段的多孔硅薄膜的拉曼频移,对多孔硅内应变引起的频移改变量和纳米硅晶粒因声子限制效应引起的频移改变量进行分离,找到多孔硅薄膜残余应力与拉曼频移之间的关系式。利用这一关系式,对不同孔隙率的多孔硅薄膜的残余应力进行了计算,获得了和声子模型拟合方法相一致的结果。研究中发现,多孔硅表面残余应力随孔隙率的增加而线性增大,其原因为随着孔隙率的增加,多孔硅晶格常数增大,且干燥过程中残液的蒸发产生的毛细应力使多孔硅薄膜与基体硅间晶格错配程度增大造成的。     

The electrical and optical properties of AZO thin film under different post-annealing temperatures

In this study, the Aluminum element doped zinc oxide (Al:ZnO) thin film was deposited on the Corning glass substrate by RF magnetron sputtering technology and annealing treatment. After sputtering, all thin films are then annealed on nitrogen atmosphere and temperature of 300, 500 and 550 °C, respectively. The structural, electric and optical characteristics were then investigated. All films illustrate strong (002) for ZnO and (335) for Al preferential orientation by using XRD analysis. The lower resistivity can be observed at nitrogen annealing and temperature of 400 °C. The transmittance property of AZO thin film exhibited an excellent transparency in the visible light range. The transmittance reached to nearly 81.4 % for all Al:ZnO film. It can be clearly observed that the grain size of AZO thin film is very uniform by utilizing SEM technology.     

Low temperature carbon nanotube and hexagonal diamond deposition with photo-enhanced chemical vapor deposition

Deposition of carbon nanotube and hexagonal diamond thin films at low substrate temperature with photo-enhanced chemical vapor deposition is described here. Extensive experimentation is conducted to optimize the catalyst layer utilized for deposition by varying Al/Ni/Al metal layer thicknesses on SiO₂ coated Si substrates. The coated substrates are annealed to transform the thin metal layers into nanoparticles. Suitable catalyst layer thicknesses obtained are 3/2/3, 5/1/5 and 5/3/5 nm for Al/Ni/Al sandwich metal layers. Suitable annealing conditions are in the range of 350–450 °C for substrate temperature and from 0.22 to 10 Torr for chamber pressure in ammonia ambient for 25 min. Carbon tetrachloride (CCl₄) is used as a carbon precursor in this work. Argon to CCl₄ flow ratio is varied in 1.5–19 range, chamber pressure is varied in 3–10 Torr range, and the substrate temperature is varied in 350–450 °C range. Carbon nanotubes (CNT) growth is observed at lower chamber pressure, lower partial pressure of CCl₄, lower substrate temperature and for thin Ni catalyst layer. The optimal CNT deposition condition observed is 5 Torr total chamber pressure, 9:1 partial pressure ratio of Ar to CCl₄, 400 °C substrate temperature and 5/1/5 nm thick Al/Ni/Al catalyst layers. The hexagonal diamond deposition is observed at a higher chamber pressure, higher partial pressure of CCl₄, higher substrate temperature and for a thicker Ni catalyst layer. The optimal condition for hexagonal diamond deposition observed is 10 Torr total chamber pressure, 7:3 partial pressure ratio of Ar to CCl₄, 450 °C substrate temperature and 5/3/5 nm thick Al/Ni/Al catalyst sandwich layers.     

硼掺杂对微波等离子体化学气相沉积制备 金刚石薄膜高择优取向生长的影响

硼(B)掺杂金刚石薄膜因其优异的电化学性能在电化学传感领域获得了广泛的应用.文章采用微波等离子体化学气相沉积法制备硼掺杂金刚石薄膜,通过硼/碳(B/C)比例和工艺参数的调节,成功制备了具备(100)择优取向的金刚石薄膜,分析了B元素影响(100)晶面形成的机理,并进一步探讨了衬底温度、碳源浓度对金刚石薄膜微观形貌的影响.实验发现:B/C比例浓度对金刚石薄膜形貌的影响要大于温度、CH4浓度等其他参数,尤其当B/C=4000 ppm时,形成的四面体形状金刚石颗粒质量最好,晶棱清晰可见,晶面光滑平整;当B/C浓度恒定时,温度与CH4浓度对金刚石薄膜的影响都是通过影响二次形核密度实现的.研究表明,通过适合的硼掺杂比例可以实现高择优取向金刚石薄膜电极的制备.     

Enhancement of microfluidic efficiency with nanocrystalline diamond interlayer in the ZnO-based surface acoustic wave device

Ultra-smooth nanocrystalline diamond (UNCD) films with high-acoustic wave velocity were introduced into ZnO-based surface acoustic wave (SAW) devices to enhance their microfluidic efficiency by reducing the acoustic energy dissipation into the silicon substrate and improving the acoustic properties of the SAW devices. Microfluidic efficiency of the ZnO-based SAW devices with and without UNCD inter layers was investigated and compared. Results showed that the pumping velocities increase with the input power and those of the ZnO/UNCD/Si devices are much larger than those of the ZnO/Si devices at the same power. The jetting efficiency of the droplet was improved by introducing the UNCD interlayer into the ZnO/Si SAW device. Improvement in the microfluidic efficiency is mainly attributed to the diamond layer, which restrains the acoustic wave to propagate in the top layer rather than dissipating into the substrate.     

新型温湿敏集成传感器研制

本文介绍了一种新的湿敏薄膜材料Ta_2O_5和一种新的硅衬底材料SOI/SDB的制备技术及它们的特性,给出了包含P-N结温敏元件的FET湿度的传感器结构及其特点.     

Piezoelectrically actuated dome-shaped diaphragm micropump

This paper describes a piezoelectric micropump built on a dome-shaped diaphragm with one-way parylene valves. The micropump uses piezoelectric ZnO film (less than 10 /spl mu/m thick) to actuate a parylene dome diaphragm, which is fabricated with an innovative, IC-compatible process on a silicon substrate. Piezoelectric ZnO film is sputter-deposited on a parylene dome diaphragm with its C-axis oriented perpendicular to the dome surface. Two one-way check valves (made of parylene) are integrated with a piezoelectrically actuated dome diaphragm to form a multi-chip micropump. The fabricated micropump (10/spl times/10/spl times/1.6 mm/sup 3/) consumes extremely low power (i.e., 3 mW to pump 3.2 /spl mu/L/min) and shows negligible leak up to 700 Pa static differential pressure.     

氧化钒薄膜的有机溶胶-凝胶制备及电学性能研究

采用V2O5粉末为原料、苯甲醇、异丁醇为溶剂,通过溶胶-凝胶工艺在玻璃衬底上制备了用于非制冷红外探测器件热敏材料的氧化钒薄膜。利用四探针、椭偏仪、XPS等技术,分别测量所制备薄膜的电阻、厚度和化学成分,总结出前驱溶液配比、退火温度、膜厚等因素对薄膜电学性能的影响。结果表明,利用原料配比为V2O5：异丁醇：苯甲醇（g：mol：mol）=1：40：4的前驱溶液,所制备的厚度为440hm的氧化钒薄膜,并经500℃退火处理,显示出的电学性能最为理想,此时氧化钒薄膜的方阻为52．284kΩ（30℃）,TCR为-3．43％／K（30℃）。     

多晶硅薄膜的结构与电学特性关系的研究

多晶硅薄膜的性质与膜的结构有密切关系。界面结构主要指晶粒尺寸、择优取向及其结构。多晶硅薄膜的结构主要由沉积条件、膜厚、掺杂条件和后来的退火温度和退火时间所决定。本文讨论了用常规低压化学汽相淀积（ＬＰＣＶＤ）方法制备的多晶硅薄膜的结构特性，初步获得了提高多晶硅压力传感器灵敏度及其温度稳定性的条件。     

Rapid thermal annealing of polysilicon thin films

In comparison with conventional heat treatment, high-temperature rapid thermal annealing (RTA) in a radio frequency (RF) induction-heated system can reduce or eliminate residual stresses in thin films in a few seconds. In this work, changes in the stress level due to the RTA of polycrystalline silicon thin films were studied as a function of annealing time and temperature. The corresponding variations in the microstructure and surface layer of the thin films were experimentally investigated by a variety of analytical tools. The results suggest that the residual stress evolution during annealing is dominated by two mechanisms: 1) microstructure variations of the polysilicon thin film and 2) effects of a surface layer formed during the heat treatment. The fact that the microstructure changes are more pronounced in samples after conventional heat treatment implies that the effects of the formed surface layer may dominate the final state of the residual stress in the thin film