Etched films, photo/thermal

Plasma Etching of Poly[A A -(/),/> -Oxydiphenylene) Pyromellitimide] Film and Photo/Thermal Degradation of Etched and Unetched Film... 

The desired thickness of the film for the solar sail application was 2.5 ym, but the thinnest commercially available film of this type was Du Font s Kapton O) with a thickness of <7.5 ym. Hence, a need existed to thin the latter film and to assess the photo-and thermal stability of the resulting, thinned film. This paper describes the use of a radiofrequency (RF) oxygen plasma for etching (thinning) of poly[, N-oxydiphenylene) pyromellitimide] (POP) film, and presents data on the photo/thermal degradation of etched and unetched film in vacuum. Although plasma etching has been applied to many polymers, it has scarcely been used on... 

Photo/thermal Degradation. Samples of etched ( <2.5 pm) and unetched ( X/7.5 pm) POP film were placed in quartz tubes which were continuously evacuated while being heated at temperatures >450 C in a constant temperature block, controlled to 2 C. Other film samples contained in quartz tubes evacuated to <10 Torr were exposed to a Hanovia 450-watt mercury lamp with the etched side facing the lamp. At 14 cm from the lamp, the intensity of the uv radiation incident on the films was equivalent to <5.9 times that of the Sun in the 2000-3500-A range at 1 astronomical unit, i.e., just outside the atmosphere. At that distance from the lamp, the temperature of... 

Photo/thermal Degradation. Although transmission or ATR IR spectra gave no Indication of a photo- or thermally-induced alteration In the POP microstructure, the uv-lrradlated or heated films showed a definite darkening or blackening. As may be seen from Table II, the rates for photolnduced blackening In etched and... 

When a neat chlorinated poly(methylstyrene) film is irradiated by 308 nm pulses at low fiuences (e.g., F = 0.23 J/cm, surface roughening due to melting is clearly evident (Fig. 5a). In the intermediate fiuence (/.c., 0.8 J/cm F 0.4 J/cm, the etched surface is quite smooth (Fig. 5b). The topographical features associated with thermal melting, material flow and resolidification are not so evident from the SEM photos (Fig. 5a) as in the low fiuence region (Fig. 5b). There are formations of bubbles and holes in... 

Inorganic Thin Coating Filins. One of the photo-assisted approaches for micropatteming of sol-gel derived films is based on the use of laser light to thermally density local regions in the films. The undensified regions can be etched away to produce surface features. 

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