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In this work, we report the preparation of phospho-silicate-glass (PSG) films using RF magnetron sputtering process and its application as a sacrificial layer in surface micromachining technology. For this purpose, a 76 mm diameter target of phosphorus-doped silicon dioxide was prepared by conventional solid-state reaction route using P2O5 and SiO2 powders. The PSG films were deposited in a RF (13.56 MHz) magnetron sputtering system at 200-300 W RF power, 10-20 mTorr pressure and 45 mm target-to-substrate spacing without external substrate heating. To confirm the presence of phosphorus in the deposited films, hot-probe test and sheet resistance measurements were performed on silicon wafers following deposition of PSG film and a drive-in step. As a final confirmatory test, a p-n diode was fabricated in a p-type Si wafer using the deposited film as a source of phosphorus diffusion. The phosphorus concentration in the target and the deposited film were analyzed using energy dispersive X-rays (EDAX) tool. The etch rate of the PSG film in buffered HF was measured to be about 30 times higher as compared to that of thermally grown SiO2 films. The application of RF sputtered PSG film as sacrificial layer in surface micromachining technology has been explored. To demonstrate the compatibility with MEMS process, micro-cantilevers and micro-bridges of silicon nitride were fabricated using RF sputtered PSG as a sacrificial layer in surface micromachining. It is envisaged that the lower deposition temperature in RF sputtering (<150 °C) compared to CVD process for PSG film preparation is advantageous, particularly for making MEMS on temperature sensitive substrates. 相似文献
23.
《Microelectronics Reliability》2014,54(9-10):1794-1797
Focused Ion Beam (FIB) micromachining of Solid Immersion Lenses (SILs) in substrate material offers optical analysis solutions for current and future technologies without the limitations of external SIL systems. This work presents an efficient single iteration calibration algorithm. This algorithm enables the implementation of FIB created SILs using a variety of substrate materials, process chemistries and most importantly different SIL shapes to match sample thicknesses. The successful application on silicon and silicon carbide is presented by creating a 50 μm wide refractive lens segment with a radius of curvature of 60 μm. Laser scanning microscope images of a silicon sample demonstrate the optical benefit with a measured resolution of 274 nm. 相似文献
24.
Work is being undertaken to produce an uncooled pyroelectric infra-red detector array which incorporates within its structure, an array of radiation collectors made by the bulk micro-machining of silicon. Development aspects of the processing route are presented here. 相似文献
25.
We present a normally closed electrostatically driven 3-way microvalve which is able to meet the requirements of industrial
applications like small form factor, high flow rate, low weight, low power consumption and a short response time. The microvalve
consists of a 3 layer full-wafer bonded silicon chip stack mounted on a ceramics substrate and a plastic cap covering the
valve. A driver electronics which converts the TTL level to the actuation voltage of 200 V is placed on top of the valve.
The valve operates in a pressure range of up to 8 bar and offers a flow rate of approximately 500 sccm. Due to the electrostatic
actuation principle the peak power consumption is below 10 mW and the response time is below 1 ms. 相似文献
26.
A better understanding of high rate anodic dissolution processes is urgently required for electrochemical micromachining (EMM) to become a widely employed manufacturing process in the electronic and precision manufacturing industries particularly in the micromanufacturing domain. A successful attempt has been made to develop an EMM setup for carrying out in depth independent research for achieving satisfactory control of electrochemical machining process parameters to meet the micromachining requirements. The developed EMM setup mainly consists of various sub-components and systems, e.g., mechanical machining unit, microtooling system, electrical power and controlling system and controlled electrolyte flow system, etc. All these system components are integrated in such a way that the developed EMM system setup will be capable of performing basic and fundamental research in the area of EMM fulfilling the requirements of micromachining objectives. 相似文献
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28.
Xiang-meng Jing Dong-ming Fang Chuang Huang Jing-quan Liu Xiang Chen 《Microelectronics Journal》2007,38(1):120-124
A novel method for fabrication of multi-layer microstructures of microelectro-mechanical system (MEMS) devices is described. This technique, which combines bulk silicon micromachining technique and UV-LIGA technique can overcome some shape limitations of single technique on complex microstructures. To demonstrate this combination, the SU-8 microstructure fabricated in the etched silicon grooves is presented. In this fabrication process, a SU-8 removal method by fuming sulfuric acid was introduced and a novel type of plastics PETG was tried in microhot embossing process. The proposed fabrication process can be applied to fabricating a high-aspect-ratio microstructure for a large displacement actuator and precision sensors. Moreover, this combined process enables the fabrication of more complex structures, which cannot be fabricated by bulk micromachining or UV-LIGA alone. 相似文献
29.
A miniaturized continuous-flow polymerase chain reaction (PCR) microfluidic chip system was developed to perform DNA amplification. This system consists of a 20-cycle continuous-flow PCR microfluidic chip, an electrical heating system and a miniature air pressure-vacuum pump. The chip was ablated with excimer laser direct-writing micromachining technique on a polymethyl methacrylate (PMMA) sheet. The ablated microchannel was inverse trapezoidal with a depth of 70 μm, top width of 200 μm and bottom width of 120 μm. Its surface roughness Ra was 1.42 μm after being treated with excimer laser polishing. The substrate sheet ablated with the microchannel was bonded with other cover sheets using hot-press bonding method to form a closed structure. The electrical heating system consisted of three groups of heating membranes, Pt100 sensors, copper blocks and PID temperature digital controllers. It could provide three distinct maintained temperature zones and a uniform temperature distribution in each zone. PCR amplification of a 170 base pair (bp) DNA fragment was carried out to validate the system's feasibility. The PCR temperatures were set as 94℃ for denaturation, 55℃ for primer annealing and 72℃ for extension. The flow rate in the microchannel was 40 nL/s and the total time for the completion of a 20-cycle amplification of 20 μL reagent was 15 min. 相似文献
30.