Effect of dose stoichiometry on the structure of vapor-deposited polyimide thin films
Autor: | C. M. Carlin, W. N. Unertl, R. G. Pethe, H.H. Patterson |
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Rok vydání: | 1993 |
Předmět: |
Pyromellitic dianhydride
Materials science Mechanical Engineering Substrate (electronics) Chemical vapor deposition Condensed Matter Physics 4 4'-Oxydianiline chemistry.chemical_compound Chemical engineering chemistry Mechanics of Materials Polymer chemistry Molecule General Materials Science Thin film Polyimide Stoichiometry |
Zdroj: | Journal of Materials Research. 8:3218-3228 |
ISSN: | 2044-5326 0884-2914 |
Popis: | PMDA-ODA polyimide thin films can be formed by vapor co-deposition of the precursor molecules PMDA (pyromellitic dianhydride) and ODA (4, 4′-oxydianiline) if the resulting polyamic acid film is heated to a 473 to 573 K cure step. We have used laser Raman spectroscopy to study how dose composition, dose rate, and substrate temperature influence the properties of the resulting polyimide films. We find that only doses with excess PMDA produce high quality films. Doses with 1 : 1 stoichiometry or excess ODA produce thermally unstable films that contain imine bonds; these films decompose below 575 K. Dosing onto substrates below 315 K produces the polyamic acid precursor of polyimide. At higher substrate temperatures, films with high defect densities or decomposed films are produced. The equilibrium vapor pressures of ODA and PMDA are reported. |
Databáze: | OpenAIRE |
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