Coating silicon nitride

Experiments like those described above have been performed to evaluate sodium ion barrier properties of Hitachi PIQ and DuPont PI 2540 polyimide films. Also included in the comparison were silicon nitride coatings plasma deposited in both tensile and compressive stress modes. The structure of the samples is illustrated in Figure 9. N-type, (111) oriented silicon substrates were cleaned and oxidized in dry oxygen ambient at 1100°C to form a 1060 A Si02 film. Wafers intended for polyimide characterization were coated with an organic silane film (gamma glycidal amino propyl trimethoxysilane) to promote adhesion of the polyimide to the oxide surface. The polyimide resins were spun onto the wafers at speeds to produce final... 

Fig. 40 Conducting film, plasma polymerised from 2-iodothiophene, on silicon. Left topography contrast (shaded pseudo-3D-image) with 405 nm corrugation. Middle real part (conductivity), with a contrast of 2.8 nA. Right imaginary part (capacity), with a contrast of 270 pA, the a.c. currents shown in the middle and in the right image were simultaneously measured together with the topography. The cantilever is made of silicon nitride coated with gold. The excitation is 0.8 V at 60 kHz, the scan speed is 4.17 pm/s...

Tool materials Low additive silicon nitride and same silicon nitride coated with multilayer CVD (alumina-TiCN/TiN)... 

Figure 28.21 Chemical structures of monomers used for the crosslinking of SAMs by electron beams on gold (52) and silicon nitride (53) and Mo-catalyzed alkyne metathesis or Cu-catalyzed alkyne homo-coupling on silicon oxide- or silicon nitride-coated substrates (54-56).

Methods. Physical adsorption. PEO was adsorbed either onto the silicon nitride cantilever tip or onto a piece of silicon nitride coated silicon wafer. The substrates were cleaned by placing them in an oxygen plasma (200 mm Hg, 25 W) for 5 minutes. Adsorption of the PEO to the clean surface was accomplished by placing the cantilever or the wafer piece in a 0.1% w/v solution of PEO in water. Adsorption was allowed to take place for at least 18 hours (sometimes as much as a week). The substrate was then placed in water for 22-24 hours to allow desorption of the weakly bound polymer chains. The substrate was vacuum dried prior to use. 

Table 1. Summary of ESCA data for silicon nitride cantilevers as received and oxygen plasma modified and for a silicon nitride coated silicon wafer as received, oxygen plasma modified, APS modified, PEG bound and PEO adsorbed. The values are in atomic percent. The numbers in the parentheses in the carbon column indicate what percentage of carbon is in the ether form...

For the physically adsorbed PEO, high molecular weight polymer was be used to prevent spontaneous desorption of the polymer. Although each segment of the PEO adsorbed to the surface may have an interaction energy of a few tenths of a kT, there are so many contacts that adsorption is essentially irreversible (29). Any loosely bound polymer was allowed to desorb by placing the cantilever or silicon nitride coated silicon wafer in polymer-free solution. The ESCA results indicate that of the 12 % of the carbon detected on the surface, 51 % of it is in the ether form. This demonstrates that PEO is present on the surface. 

Ellipsometric measurements of the PEO 900 kDa physically adsorbed layer on the plasma cleaned silicon nitride coated wafer indicate that the PEO layer thickness in air is 1.94 + 0.10 nm using a measured refractive index of 1.94 for silicon nitride and an assumed refractive index of 1.45 for PEO in air. 

Silicon nitride coated CNT-templated Basic Blue 7 478.3 [Ml Kanyal et al. [2]... 

Silicon nitride coated CNT-templated UTLC plates were employed for analyte detection via DESI-MSI and direct analysis in real-time mass spectrometry (DART-MS) after chromatography. Rhodamine B (m/z 443.2 M+) and Basic Blue 7 (m/z 478.3 M ) were desorbed with methanol as spray solvent at 0.003 mL min within 45 min for scanning an 85-mm plate section (Figure 9.9). Dimethyl Yellow (m/z 226 [M-i-H]+), Oracet Red G (m/z 238 [M-i-H]+), Solvent Blue 35 (m/z 351 [M-t-H]+), Sudan Red G (m/z 279 [M-i-H]+), and Solvent Blue 22 (m/z 305 [M-i-H]+) were detected within 3.5 min with a snbstantially optimized interface for HPTLC-DART-MS applying a helium flow of 3 L min at 500°C (Figure 9.10) [2]. 

Silicon nitride (Si3N4) is a major industrial material which is produced extensively by CVD for electronic and structural applications. It is an excellent electrical insulator and diffusion barrier (to sodium and water vapor) and has replaced CVD oxides in many semiconductor devices.l l Silicon nitride coatings are produced by the reaction of silicon tetrachloride (SiCl4) with ammonia ... 

For instance, a silicon nitride coating can be produced by activating a silica gel substrate by chemisorption of trichorosilane, reacting with ammonia and heating to 500 °C. 

As silicon nitride has a higher density than amorphous silicon oxide, it will serve as a better barrier to metal atom diffusion, and consequently it is used in VLSI production to prevent the cross-penetration of dopant atoms from one region of the device to another. During the manufacture of devices based on gallium arsenide, silicon nitride coatings will prevent the evaporation of (toxic) arsenic. Further information on the use of silicon nitride in semiconductor processing is available elsewhere (Belyi et al., 1988). 

Development of plasma sprayed silicon/silicon nitride coatings hy in-sim nitridation, in Thermische Spritzkonferenz TS96, vol. 175 (ed. E. Lugscheider),... 

Heimann, R.B. (2010) Thermal spraying of silicon nitride coatings using highly accelerated presursor powder particles. Surf. Coat. Technol, doi 10.1016/j. surfcoat.2010.02.049. 

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