PDMS spreading morphological patterns on substrates of different hydrophilicity in air vacuum and water


Autoria(s): Frost, Ray L.; Zbik, Marek
Data(s)

15/04/2010

Resumo

In paper has been to investigate the morphological patterns and kinetics of PDMS spreading on silicon wafer using combination of techniques like ellipsometry, atomic force microscope (AFM), scanning electron microscope (SEM) and optical microscopy. A macroscopic silicone oil drops as well as PDMS water based emulsions were studied after deposition on a flat surface of silicon wafer in air, water and vacuum. our own measurements using an imaging ellipsometer, which also clearly shows the presence of a precursor film. The diffusion constant of this film, measured with a 60 000 cS PDMS sample spreading on a hydrophilic silicon wafer, is Df = 1.4  10-11 m2/s. Regardless of their size, density and method of deposition, droplets on both types of wafer (hydrophilic and hydrophobic) flatten out over a period of many hours, up to 3 days. During this process neighbouring droplets may coalesce, but there is strong evidence that some of the PDMS from the droplets migrates into a thin, continuous film that covers the surface in between droplets. The thin film appears to be ubiquitous if there has been any deposition of PDMS. However, this statement needs further verification. One question is whether the film forms immediately after forced drying, or whether in some or all cases it only forms by spreading from isolated droplets as they slowly flatten out.

Formato

application/pdf

Identificador

http://eprints.qut.edu.au/31240/

Publicador

Elsevier

Relação

http://eprints.qut.edu.au/31240/1/c31240.pdf

DOI:10.1016/j.jcis.2009.12.065

Frost, Ray L. & Zbik, Marek (2010) PDMS spreading morphological patterns on substrates of different hydrophilicity in air vacuum and water. Journal of Colloid and Interface Science, 344(2), pp. 563-574.

Direitos

Copyright 2010 Elsevier

Fonte

Chemistry; Faculty of Science and Technology

Palavras-Chave #030603 Colloid and Surface Chemistry #030600 PHYSICAL CHEMISTRY (INCL. STRUCTURAL) #030606 Structural Chemistry and Spectroscopy #PDMS, Silicone oil, Spreading
Tipo

Journal Article