Molecular spin coating

Fig. 14 The molecular structures of BP-BTE and DHBO above). Microsized erasable ESIPT-fluorescence photoimaging on a spin-coated BP-BTE/DHBO-loaded PMMA film and its nondestructive readout capability (a) initial open-form state (b) writing (c) erasing (d) rewriting and (e) continuous nondestructive reading under irradiation with relatively high-intensity 415 nm light (200 4W cm-2) for 30 min. The dark region represents the area irradiated with the 365 nm UV light below) (reprint from ref. [88], Copyright 2006 American Chemical Society)...

Phthalocyanine-based dyes are especially useful for CD-R, as the chromophore absorption band falls in the desirable spectral range, and they are noted for excellent photostability. Unlike cyanine dyes, phthalocyanines tend to have very poor solubility, particularly in solvents such as alcohols and aliphatic hydrocarbons (which do not attack polycarbonate and are therefore used for spin coating). Therefore, the main barrier to the wider use of these dyes is the relatively high cost of synthesizing soluble derivatives. Suitable modifications to the Pc core which have been developed, notably by Mitsui Toatsu, are shown in Scheme 7. The bulky R groups reduce undesirable molecular association (which in turn lower the extinction coefficient and hence reflectivity), whereas partial bromination allows fine-tuning of the film absorbance and reflectivity. The metal atom influences the position of the absorption band, the photostability, and the efficiency of the radiationless transition from the excited state.199 This material is marketed by Ciba as Supergreen.204... 

Chemical Vapor Deposition Electrochemical Deposition Molecular Beam Epitaxy Atomic Layer Deposition Thermal Oxidation Spin Coating... 

Solubility of polymers in tetramethyl ammonium hydroxide aqueous solution was measured by dipping the wafer on which the polymer solution was spin-coated, for 1 min. at 25°C. The prebake was carried out at 90°C for 5min. Sensitivity of resists was measured after the exposure with CA 800(Cobilt) or KrF excimer laser(0.9mJ/cm2/1 pulse). The polymer structure was determined by iH-NMR, 13C-NMR(FX90Q apparatus,JEOL) and 2 Si-NMR. The molecular weight distribution was determined with a Toyo Soda Model 801 gel permeation chromatograph at 40°C. The four columns were connected in series, each packed with G-2000H8x3 and G-400H8(Toyo Soda polystylene gel), respectively. 

SPIN-COATING Polymer composition Molecular weight Solvent boiling point Solvent vapor pressure Solution viscosity Solution concentration Spinning speed Acceleration Temperature Humidity Filtration... 

Schmidt RH, Mosbach K, Haupt K. A simple method for spin-coating molecularly imprinted polymer films of controlled thickness and porosity. Adv Mater 2004 16 719. 

Figure 17 shows the temperature dependence of the lateral forces measured at the scanning rate of 10 nms for a high-density PMMA brush (a = 0.8 chains nm ) and an equivalent spin-coated film. The a-relaxation process was clearly observed accompanying a small peak, which was assigned to a surface /1-process. They commented that the surface molecular motion of the brush layer possibly differs from that of the spin-coated film but that it was rather difficult to conclude this because of shghtly scattered data. 

The solutions of aldehyde copolymers prepared by diethylaluminum diphenylamide were usually highly viscous owing to their high molecular weights and where rather difficult to spin-coat onto a silicon wafer. The molecular weight could be controlled by changing the amount of initiator used in the polymerization. Table IX shows the electron-beam exposure... 

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