A formation of Organic Rewritable Optical Memory Media Using the Vapor Transportation Method

摘要

Organic molecules have been widely used in production of opto-electronic devices, such as liquid crystal displays (LCD), compact disks-recordable (CD-R) media, electro-luminescence (EL) devices,~(1-3) thin film transistors,~3,4 solar cells,~1,5 etc. Methods using an organic thin film and/or a thin layer are the important techniques used in the production of these devices iwth complex structures, but there are many problems with the present methods. The vacuum vapor deposition process, which is used for compounds with high vapor pressure, is widely used, but organic compounds make some decomposition during the evaporation process. Wet processes with organic solvents such as casting and spin-coating are more commonly used for the formation of organic thin films. However, it is difficult to remove residual solvent molecules from films, the thicknesses of which are over 500 nm. Small amounts of residual solvent in the films often cause Rayleigh scattering or convert into the gas phase, causing small cracks after heating by application of bias voltage or by irradiation with focused light.~6,7