Polymer Insulators

A disadvantage of AES is that the intense electron beam easily causes damage to sensitive materials (polymers, insulators, adsorbate layers). Charging of insulating samples also causes serious problems. 

C. C. Shiflett, D. B. BuchhoF, and C. C. Faudskar, "High-Density Multilayer Hybrid Circuits Made with Polymer Insulating Layers (Polyhic s)," Society of Hybrid Microelectronics Proceedings, 1980, pp. 481—486. 

The application of PIXE (Proton Induced X-Ray Emission) and micro-PIXE to quantitative analysis of impurities in polyethylene are described. The equipment, sources of background which affect the sensitivity and the precision of PIXE measurements are discussed for both thick and thin targets. A number of applications of micro-PIXE to the identification and location of trace elements in the "Trees" found in the polymer insulation of HV cables are presented. 

Polychlorinated biphenyls (PCBs) are mixtures of biphenyls with 1 to 10 chlorine atoms per molecule. They are oily fluids with high boiling points, great chemical resistance, and low electrical conductivity, and have been used as plasticizers in polyvinyl polymers, insulators and coolants in transformers and heat exchange fluids. Dioxins and furans (see Section 9.1) are not produced intentionally but are derived from combustion processes of chlorinated aromatic hydrocarbons, pesticides and chlorinated solvents. 

H. Janssen, U. Stietzel Contact angle measurement on clean and polluted high-voltage polymer insulators in 10th ISH, Conf. Proc. Vol. 3, p. 149 - 152, Montreal, August 1997. 

Polymer Insulating Layers for Multilayer Hybrid Circuits... 

Figure 1.2 illustrates the typical design of a printed transistor the source and drain electrodes are mounted on a polyester foil, followed by the semiconducting layer of polymer (i.e. polythiophenes), the insulating layer of polymer insulators is on top and, as the final layer, the gate electrode. 

Figure 24.3 (a) Profile of the realised OFET structures, (b) realised MIS-diode profile, (c) polymer insulators used for the OFET realisation. 

At this point of our understanding, the question arises whether one ean modify interfaeial traps of a polymer insulator surfaee in sueh a way that one gains eontrol over the electron transport in a transistor, e.g. by the introduction of -OH groups to an otherwise -OH free PMMA surface. Following earlier publications on modification of polymer surfaces, one can introduce keto and hydroxyl groups by exposing a PMMA dielectric to UV radiation in ambient atmosphere [42, 43]. Therefore, for the following experiments, the PMMA dielectric layer is exposed to 254 nm radiation for a time frame of 10 minutes and an optical power of 15 mW/cm prior to the pentacene deposition. 

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