Dielectrics inorganic

Figure 12.5. Photograph of microdispensing system depositing an inorganic dielectric dispersion onto a patterned, metallized polyester film. The pattern is of a transistor gate electrode array. The microdispensing head atomizes the dispersion, generating a liquid spray much like a dual orifice atomizer found on an airbrush.

D. Knipp, R. A. Street, A. Volkel, J. Ho, Pentacene thin film transistors on inorganic dielectrics Morphology, structural properties, and electronic... 

Evaporation is suitable for all metals (the most refractory metals cannot be thermally evaporated, but can be e-beam evaporated), a few sublimable organic and organometallic compounds such as the phthalocyanines, and a relatively small number of inorganic dielectric materials, such as Mgp2 and SnC>2. Nearly all polymers decompose in one manner or another before a high enough temperature is obtained for them to become mobile in the vapor phase. 

Although the surface of most IC chips has been passivated with a layer of inorganic dielectric material such as silicon dioxide or silicon nitride (polyimides have also been used as final passivating layers), the protection provided by such layers is not sufficient to ensure reliable operation throughout the lifetime of the device. The three basic methods of protection are... 

In this connection, the application of inorganic dielectric nanocrystals based on the activated compounds of rare-earth elements seems to be prospective. Such compounds are non-toxic and have intensive luminescence, narrow spectral lines and high photostability. Furthermore, these nanocrystals can be obtained in aqueous solutions that is very important for biological applications [3]. 

Aromatic polyimides have glass transition temperatures in excess of 400 °C, excellent toughness and elongation properties and dielectric constants comparable to that of inorganic dielectrics, about 3.5. An important feature relative to these applications is their ability to planarize the topography when spun on as the soluble precursor polyamic acid. The subsequent intramolecular condensation reaction to form the heterocyclic imide is typically a thermal "curing" process. 

In this chapter, a couple of recent experimental results obtained for the femtosecond laser machining of inorganic dielectrics and organic polymers are... 

As the pulse becomes shorter, the ablation threshold decreases (Fig. 34) [92, 93] in accordance with the observations for inorganic dielectrics (see Fig. 12) and the uncertainty of the threshold value is reduced (cf. Figs. 14 and 15). Thus, femtosecond pulses will produce the most reproducible cuts. 

It has been observed in several studies that the use of organic monolayers or thin polymer phases to modify the surfaces of inorganic dielectric materials often improves the performance of these devices. This strategy has been employed for modification of Si02 [58] and AI2O3 surfaces [38] and more complicated dielectric composite materials. 

Bouchoms, I.P.M., Schoonveld, W.A., Vrijmoeth J., and Klapwijk, T.M., Morphology identification of the thin film phases of vacuum evaporated pentacene on Si02, Synth. Met. 104, 175, 1999 Knipp, D., Street, R.A., Volkel, A., and Ho, J., Pentacene thin film transistors on inorganic dielectrics Morphology, stmctural properties, and electronic transport, J. Appl. Phys. 93, 347, 2003. 

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