Silicon nitride model

Fig. 6. Lateral stiffness vs. load data for a silicon nitride tip vs. mica surface in ultra-high vacuum. Solid line is fit of the JKR model to the data. Reprinted with pennission from ref. [67].

Fig. 7. Voigt model analysis of (a) lateral contact stiffness and (b) the response time, t, for a silicon nitride tip vs. poly(vinylethylene) as a function of frequency and polymer aging times. Reprinted with permission from ref [71].

The first LAPS utilized silicone nitride (S3N4) as a pH-sensitive layer [68], A light-addressable high resolution pH imaging sensor was applied to the detection of spatially resolved metabolic activity of Escherichia coli colonies on agar medium [69], For a silicone substrate thickness of 20 pm the reported spatial resolution was about 10 pm. The observed pH distribution was in good agreement with the results of simulation based on a two-dimensional diffusion model. 

This model goes a long way towards explaining most experimental results reported in the literature for ISFETs with oxide or nitride surfaces. Unfortunately, the properties of these materials prepared in different laboratories are very different. It is known that silicon nitride (really silicon oxynitride SisNztOx) forms an oxygen-rich layer at the surface, whose thickness depends on the deposition conditions. This passivation layer forms rapidly (in a matter of hours) and is very stable, even under continuous exposure to aqueous electrolyte. The hydration of this layer seems to fit the requirements and predicted behavior of the Sandifer model. Consequently, ISFETs that have been exposed to aqueous solution for more than one hour show no adsorption effects which would be expected from the SBT model. 

Ogbuji LUJT (1994) The Oxidation Process in Silicon Nitride. In Nickel KG (ed) Corrosion of Advanced Ceramics - Measurement and Modelling. Kluwer Academic Publishers, Dordrecht, p 117... 

Some reviews [5-7] have appeared on NCE-electrospray ionization-mass spectrometry (NCE-ESI-MS) discussing various factors responsible for detection. Recently, Zamfir [8] reviewed sheathless interfacing in NCE-ESI-MS in which the authors discussed several issues related to sheathless interfaces. Feustel et al. [9] attempted to couple mass spectrometry with microfluidic devices in 1994. Other developments in mass spectroscopy have been made by different workers. McGruer and Karger [10] successfully interfaced a microchip with an electrospray mass spectrometer and achieved detection limits lower than 6x 10-8 mole for myoglobin. Ramsey and Ramsey [11] developed electrospray from small channels etched on glass planar substrates and tested its successful application in an ion trap mass spectrometer for tetrabutylammonium iodide as model compound. Desai et al. [12] reported an electrospray microdevice with an integrated particle filter on silicon nitride. 

Melendez-Martinez, J J., Gomez-Garcla, D., and Dominguez-Rodriguez, A., Acritical analysis and a recent improvement of the two-dimensional model for solution-precipitation creep application to silicon nitride ceramics , Phil. Mag., 2004, 84, 2305-16. 

This approach was successfully used in modeling the CVD of silicon nitride (Si3N4) films [18, 19, 22, 23]. Alternatively, molecular dynamics (MD) simulations can be used instead of or in combination with the MC approach to simulate kinetic steps of film evolution during the growth process (see, for example, a study of Zr02 deposition on the Si(100) surface [24]). Finally, the results of these simulations (overall reaction constants and film characteristics) can be used in the subsequent reactor modeling and the detailed calculations of film structure and properties, including defects and impurities. 

In all of the AFM studies mentioned above, the system contained monovalent counterions, and hence the Poisson-Boltzmann theory could be expected to be accurate. Kekicheff et al. [62] studied interactions between mica surfaces and between silicon nitride and mica in Ca(N03) solutions by using both the SFA and AFM methods. As discussed above, the presence of a divalent counterion complicates particle-surface interactions significantly. Both experimental methods showed that there is a strong, attractive force at very small surface separations, a result that could not be explained by the Poisson-Boltzmann equation. The authors interpreted their results by using the AHNC described above, with the primitive model... 

Tossell, J. A., and G. V. Gibbs (1978). The use of molecular orbital calculations on model systems for the prediction of bridging-bond-angle variations in siloxanes, silicates, silicon nitrides and silicon sulfides. Acta. Cryst. A34, 463-72. 

In the present study, we propose a new equation to predict the planarity after STI CMP process by erosion modeling which incorporates active pattern density, initial step height, selectivity between oxide and silicon nitride and over CMP amounts. 

Ma SH, Lepak LA, Hussain RJ, Shain W, Shuler ML. An endothelial and astrocyte co-culture model of the blood-brain barrier utilizing an ultra-thin, nanofabricated silicon nitride membrane. Lab Chip 2005 5 74-85. 

Fig. 4.4 F-d curves recorded with a silicon nitride tip in ambient on (a) CH3 and (b) COOH terminated areas of a patterned SAM model surface, (c) Pull-off force histogram calculated from 4096 individual f-d curves, (d) Corresponding quantitative pull-off force map [22]...

The model of Monthioux et al. describes the crystallization behavior of SiC also for more complex precursor systems Si-C-N, Si-C-0, and Si-C-N-0. In the case of nitrogen-containing systems it has been observed [158] that, beside the bulk mechanism based on BSUs discussed above another mechanism, a surface mechanism may also occur. Especially on surfaces of fibers derived from polycarbosilazanes, needle-like silicon nitride crystals are formed under a nitrogen atmosphere via gas phase processes at T > 1600 C. 

On the basis of our results using scanning force microscopy such as S VM and LFM, we claim that the mobility at the surface of PS films is not the same as that in the bulk. However, in such measurements, a probe tip made of silicon or silicon nitride makes contact with the surface to be measured. This may induce some artifacts in the results. If an effect of tip contact on the surface dynamics cannot be negligible, our conclusion must be reconsidered. Thus, T is here discussed on the basis of coarse-grained molecular dynamics simulation using a bead-spring model of Grest... 

W. Dressier, H.-J. Kleebe, M. J. Hoffmann, M. Ruble and G. Petzow, Model Experiments Concerning Abnormal Grain Growth in Silicon Nitride , J. of the Europ. Ceram. Soc., 16, 1996, 3-14. 

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