Research on the growth of dye film in vacuum in situ

Abstract

Organic film deposition in vacuum is fast developing scientific and industrial domain. We developed installation for deposition of organic films equipped with optical spectrometer for measurements in situ. We are developing new dyes aimed for application in waveguide sensor, nonlinear optics and studying film organisation during deposition. Fluorinated azo-dyes and azomethine dyes were synthesized at University of Applied Sciences Wildau and at the Institute of Organic Chemistry, Kyiv. Compounds were evaporated at a pressure of 10-3 Pa using resistive heated crucible. Glass and glass covered with polytetrafluoroethylene (PTFE) film are used as substrates. The films were studied with Polytec and StellarNet spectrometers and an atomic force microscope. Optical spectra of the dye films revealed, that some compounds were decomposed during evaporation. Several kinds of dyes were evaporated and deposited without decomposition. Some deposited films formed H-aggregates and other types of aggregates. AFM images of dye films showed that their morphology depends on the chemical structure of the compounds and on the nature of the substrate on which the film was grown.

Tuned aggregation and film self-assembly of monomethincyanine dyes through variation of their monomer structure

“…Similar result was obtained in ref. [15]. Thus, the flat molecular structure of Qu-Me allows the molecules to approach relatively small distance to each other (Table 1) and leads to formation of two types of aggregates, either H-or J-type.…”

Growth and optical properties of dye films and dye-in-polymer matrix deposited by vacuum evaporation

“…Therefore, recently the researches in the field of deposition, structure and optical properties of PMD were carried out [2,3]. The most complete information about the growth process of a dye film can be obtained using optical absorption spectroscopy in situ [4]. Recently we found that polytetrafluoroethylene (PTFE) matrix influences on the properties of dye clusters [5][6][7].…”

“…The most complete information about the growth process of a dye film can be obtained using optical absorption spectroscopy in situ [4]. Recently we found that polytetrafluoroethylene (PTFE) matrix influences on the properties of dye clusters [5][6][7].…”