Silicon microfabrication

Microfabricated silicon mixers for submillisecond quench flow analysis. Anal. 

Suzuki, K. and Masuhara, H. (2005) Groove-spanning behavior of lipid membranes on microfabricated silicon substrates. Langmuir, 21, 6487-6494. 

Figure 6.13 Normalized force between a microfabricated silicon nitride tip of an atomic force microscope and a planar mica surface in 1-propanol at room temperature [174], The tip had a radius of curvature of R w 50 nm. The different symbols were recorded during approach (filled circles) and retraction (open circles) of the tip.

Chabri, F., et al. 2004. Microfabricated silicon microneedles for nonviral cutaneous gene delivery. 

Tai, Y.-C., Marzluff, E. M., Mayo, S. L., Microfabricated silicon mixers for submillisecond quench flow analysis. Anal. Chem. 1998, 70, 232-236. 

Cheng, J., Shoffner, M.A., Hvichia, G.E., Kricka, L.J., Wilding, P., Chip PCR. II. Investigation of different PCR amplification systems in microfabricated silicon-glass chips. Nucleic Acids Res. 1996, 24, 380-385. 

Shoffner MA, Cheng J, Hvichia GE, Kricka LJ, Wilding P. Chip PCR. I. Surface passivation of microfabricated silicon-glass chips for PCR. Nucleic Acids Res 1996 24 375-379. 

Current instruments differ little, in principle, front the first AFM developed over I0 years ago. The biggest changes have come in the methods used to detect the deflection of the cantilever spring, as mentioned above, and the development of microfabricated silicon nitride cantilevers with integrated pyramidal tips. 

Somprasit C, Marquez-Do DA, Yamanishi D, Simpson JL, Bischoff FZ. A novel approach for enrichment of fetal cells using a microfabricated silicon membrane. Los Angelas Amer Soc Human Genet, 2003. 

Figure 1.8 Microfabricated silicon packed-bed reactor for phosgene on-demand production, (a) Top-view of reactor partially loaded with 60-mm activated carbon particles - the reactor channel is 20 mm long, and the image is spliced to fit the 20 mm reaction channel by omitting the long channel midsection ...

In the AFM, the two interacting surfaces are the planar sample surface and the surface of the AFM probe. For microscopy the most commonly used probes are the sharp microfabricated silicon nitride or silicon tips that provide a high lateral resolution. These probes also provide high resolution when measuring surface forces, but introduce the problem that the surface geometry is difficult to determine in the 10-nm regime [120-122]. This would, however, be necessary since typical radii of curvature are from 5 to 60 nm. In addition, the surface chemistry of silicon nitride tips, which are most frequently used for force measurements, is rather complex [51, 52, 123,124],... 

Fig. 7.2. Scanning electron micrograph of a microfabricated silicon nitride cantilever commonly used for force measurements. (A polystyrene microsphere glued at the end of the V-shaped cantilever can be seen pointing upward. The scale bar corresponds to 10 pm.) Reprinted from [10]. Copyright 1992, with kind permission from the American Chemical Society...

Altendorf E, Iverson E, Schutte D, Weigl B, Osborn T, Sabeti R, Yager P (1996) Optical flow cytometry utilizing microfabricated silicon flow channels Proc. SPIE 2678, 267-76... 

Frechette LG, Jacobson SA, Breuer KS, Ehrich FF, Ghodssi R, Khanna R, Wong CW, Zhang X, Schmidt MA, Epstein AH (2005) High-speed microfabricated silicon turbomachinery and fluid flhn bearings. J Microelectromech Syst 14(1) 141-152... 

Jong et al. [143]. Porous microfluidic devices were fabricated by phase separation micromolding. Oil-in-water emulsions with 190 pm size and polydispersity 2.5% were produced inside 150 pm diameter porous microchannels. Sugiura and co-workers [144—148] proposed a microfabricated silicon geometry containing at least 400 microchannels of small dimensions (typical cross-section 6x13 pm) (Figure 8.25). Not all the channels were initially active, but as the pressure of the... 

F. Chabri, K. Bouris, T. Jones, D. Barrow, A. Harm, C. Allender, K. Brain and J. Birchall, Microfabricated silicon microneedles for nonviral cutaneous gene delivery. Br. ]. Dermatol., 150, 869-877... 

A novel procedure to prepare microfabricated silicon columns (microcolumns) for fast organophosphonate and organosulfur compound separation with sharp peaks, that rivals the performance of commercial capillary columns, has been reported. Approximately 16,500 theoretical plates were generated using a 3m long OV-5-coated microcolumn with a 0.25/xm... 

Scanlon MD, Berduque A, Stratwolf J, Arrigan DWM (2010) Flow-injection amperometry at microfabricated silicon-based /x-Uquid-liquid interface arrays. Electrochim Acta 55 4234-4239... 

Harris, S. and Shuler, M.L. (2003). Growth of endothelial cells on microfabricated silicon nitride membranes for an in vitro model of the blood-brain barrier. Biotechnol. Bioprocess Eng. 8 246. 

Electrostatic Forces— The AFM Tip. The most frequently used commercial AFM tip consists of microfabricated silicon nitride. Under normal laboratory conditions, this is, in reality, an ill-defined, hydroxylated melange of silicon oxynitride and silicon dioxide, the precise composition of which depends on a combination of manufacturing conditions and tip history. An isoelectric point of around pH=5 has been firequently observed in force-distance measurements under electrolyte in our laboratory (15), suggesting the oxidized oxynitride composition mentioned above. In order to achieve a better reproducibility, however, we have adopted an oxygen plasma-treatment procedure, which leaves the tip coated with hydroxylated silica, as evidenced by an isoelectric point of around pH=3 (16), as measured by force titration (75). 

In many acute applications, microelectrodes are fixed to stationary electronics for use in anesthetized animals. For chronic use, Michigan probes have been connected to flexible polyimide interconnect cables through thermocompression gold ball bonding [48]. In this case, the polyimide cable links the microfabricated silicon probe and an external connector for long-term recording. 

Figure 6.7. Resistively heated AFM probes used for thermal imaging and thermal analysis. (A) Wollaston wire probes used in the commercial microTA system. (B) Microfabricated silicon probes with integral heaters at the base of the tip used in the commercial nanoTA. (Figure 6.7A from Anasys Instruments [134] reproduced with permission. Figure 6.7B from Hammiche and Pollack [157] unpublished.)...

Microfabricated silicon cantilever with integral probe... 

Figure 5.9 Adhesion force versus relative humidity curves, (a) A hydrophilic glass sphere of 20 pm radius interacting with a naturally oxidized silicon wafer as measured by AFM [493]. (b) Force between a microfabricated silicon nitride AFM tip and a silicon wafer [553].

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