UV laser induced refractive index modulation of liquid crystalline polymer films deposited by linearly polarized laser CVD

Autor:	Toshiaki Itadani, Koichi Saito
Rok vydání:	1998
Předmět:	Materials science Birefringence Excimer laser business.industry medicine.medical_treatment Analytical chemistry Dichroism Condensed Matter Physics Laser law.invention Optics Vacuum deposition law medicine General Materials Science sense organs Thin film business Refractive index Polyimide
Zdroj:	Materials Chemistry and Physics. 54:194-196
ISSN:	0254-0584
DOI:	10.1016/s0254-0584(98)00057-1
Popis:	The precursor of polyimide was spin coated on the substrate and cured at 180 or 240 °C for 1 h. Then, exposure of a linearly polarized KrF excimer laser to a polyimide layer was performed through a photo-mask. In both exposed and non-exposed areas, the monomers were sublimated to deposit liquid crystalline polymer films under the vacuum upon KrF excimer laser irradiation. Optical birefringence and IR dichroism indicated the molecular orientation of the film. In both exposed and non-exposed areas, the molecular orientation was higher in the case of the lower imidized surface. The molecular orientation became lower by exposure either for excess dose energy or excess pulse energy. The deposited films fabricated with periodic mask-patterns exhibited the optical diffraction due to periodic change of refractive index.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::00140fb4d01aa53251c43f2ce0a02c31 https://doi.org/10.1016/s0254-0584(98)00057-1 Zobrazit plný text záznamu Full Text from ScienceDirect