Growth and characterization of poly(arylamine) thin films prepared by vapor deposition

Thin films of new organic redox-active arylamine dendrimers have been examined. The thermal properties of the bulk samples have been measured by differential scanning calorimetry and thermogravimetric analysis. In general, these compounds exhibit amorphous phases with glass transition temperatures near 100 °C and are thermally stable up to 400 °C. Thin films (1–100 nm) of these large (1300–2200 amu) molecules were prepared by vapor deposition onto Au and Si(100) surfaces. Nuclear magnetic resonance analysis of redissolved films proved that vapor deposition occurs without molecular decomposition. Ex situ surface characterization was performed by reflection–absorption infrared spectroscopy, x-ray photoelectron spectroscopy, spectroscopic ellipsometry, and atomic-force microscopy to document the chemical integrity and morphology of the films. The analyses show that the vapor deposition produces molecularly smooth dendrimer films at high surface coverages, while at low surface coverage, film growth and morphology depend greatly on the chemical nature of the surface.