Image transfer

After image transfer, the patterned resist must be readily and completely removable without substrate damage. The pattern often can be stripped from the substrate with a mild organic solvent. Proprietary stripper formulations or plasma oxidation treatments are utilized when the imaging chemistry or image transfer process has iasolubilized the pattern. 

Polaroid introduced Polavision, a Super-8-mm instant motion picture system, in 1977 (97). Polachrome CS 35-mm sHde film followed in 1982 (98), and a high contrast version, Polachrome HCP, appeared in 1987. Each of the films comprises a very fine additive color screen and an integral silver image transfer film. The Polavision system, which included a movie camera and a player that processed the exposed film and projected the movie, is no longer on the market. The Polavision film was provided in a sealed cassette, and the film was exposed, processed, viewed, and rewound for further viewing without leaving the cassette (97). 

The Development Process. In the original electrophotographic demonstration, development was accompHshed by dusting lycopodium powder over an exposed sulfur film. This yielded low density images of poor resolution. Considerable powder settied in the exposed background areas (the white areas of a document), and image transfer to paper could only be achieved by prior coating of the paper with wax or another sticky material. 

Apple SL, Schmidt JH. Technique for neurosurgically relevant CT image transfers using inexpensive video digital technology. Surg Neurol 2000 53 411 16. 

Figure 10. Submicron features generated by e-beam imaging of 0.14 ftm of an aliphatic polysilane over 2.0 ftm of hardbaked Novolac-naphthoquinone-2-diazide photoresist 20 ftC, Oj-RIE image transfer.

Image tone/stabilization, in instant photography, 19 280-281 Image transfer devices, 15 117 Image transfer technique, 19 323... 

Figure 8. Bilayer imaging of PCHMS using a PE-500 Microalign 1 1 projection printer (UV-2 mode). 0.16 pm PCHMS over 1.0 pm of a hardbaked AZ-type photoresist. 02-RIE image transfer, 0.75-pm images.

Photodimerization of cinnamic acids and its derivatives generally proceeds with high efficiency in the crystal (176), but very inefficiently in fluid phases (177). This low efficiency in the latter phases is apparently due to the rapid deactivation of excited monomers in such phases. However, in systems in which pairs of molecules are constrained so that potentially reactive double bonds are close to one another, the reaction may proceed in reasonable yield even in fluid and disordered states. The major practical application has been for production of photoresists, that is, insoluble photoformed polymers used for image-transfer systems (printed circuits, lithography, etc.) (178). Another application, of more interest here, is the use that has been made of mono- and dicinnamates for asymmetric synthesis (179), in studies of molecular association (180), and in the mapping of the geometry of complex molecules in fluid phases (181). In all of these it is tacitly assumed that there is quasi-topochemical control in other words, that the stereochemistry of the cyclobutane dimer is related to the prereaction geometry of the monomers in the same way as for the solid-state processes. 

Figure 17. Schematic representation of image transfer efficiency for a 1 1 projection printer. (Reproduced with permission from Ref. 1)...

Schematic representation of image transfer efficiency for a 1 1 projection printer.

Figure 9. Poly silane bilayer resist, top layer 0.25 am experimental polysilane, bottom layer 1.0 am of hardbaked photoresist, projection printed at 313 nm with 02-RIE image transfer.

The use of TPX permits complete transfer of the toner from its initial carrier onto many other surfaces including of paper, card, cardboard, all of which may be uncoated or coated with many different types of finish, and of glass, ceramics, woods, metals, plastics, etc. TPX has sufficient thermal stability to be useful within the range of temperatures at which the material can be used for effecting image transfer. 

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