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Title: Method for measurement of the density of thin films of small organic molecules

Abstract

An accurate and sensitive method is reported to measure the thin-film density of vacuum-deposited, small-molecular organic semiconductor materials. A spectrophotometer and surface profiler had been used to determine the mass and thickness of organic thin film, respectively. The calculated density of tris-(8-hydroxyquinolato) aluminum (Alq{sub 3}) thin film was 1.31{+-}0.01 g/cm{sup 3}. Vacuum pressures and thin-film growth rates are found to have less impact on the thin-film density of organic material. However, the thin-film density of organic material strongly depends on its chemical structure and molecular weight. Specifically, the chemical structure determines the density of organic material that affects the molecular volume and intermolecular stacking.

Authors:
; ; ; ;  [1];  [2];  [2]
  1. Department of Electrical and Electronic Engineering, Department of Chemistry and HKU-CAS Joint Laboratory on New Materials, University of Hong Kong, Pokfulam Road, Hong Kong (China)
  2. (China)
Publication Date:
OSTI Identifier:
20953395
Resource Type:
Journal Article
Resource Relation:
Journal Name: Review of Scientific Instruments; Journal Volume: 78; Journal Issue: 3; Other Information: DOI: 10.1063/1.2712932; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ALUMINIUM; COATINGS; DENSITY; MOLECULAR STRUCTURE; MOLECULAR WEIGHT; MOLECULES; ORGANIC SEMICONDUCTORS; SPECTROPHOTOMETERS; SPECTROPHOTOMETRY; SURFACES; THICKNESS; THIN FILMS

Citation Formats

Xiang Haifeng, Xu Zongxiang, Roy, V. A. L., Che Chiming, Lai, P. T., Department of Chemistry and HKU-CAS Joint Laboratory on New Materials, University of Hong Kong, Pokfulam Road, Hong Kong, and Department of Electrical and Electronic Engineering, University of Hong Kong, Pokfulam Road, Hong Kong. Method for measurement of the density of thin films of small organic molecules. United States: N. p., 2007. Web. doi:10.1063/1.2712932.
Xiang Haifeng, Xu Zongxiang, Roy, V. A. L., Che Chiming, Lai, P. T., Department of Chemistry and HKU-CAS Joint Laboratory on New Materials, University of Hong Kong, Pokfulam Road, Hong Kong, & Department of Electrical and Electronic Engineering, University of Hong Kong, Pokfulam Road, Hong Kong. Method for measurement of the density of thin films of small organic molecules. United States. doi:10.1063/1.2712932.
Xiang Haifeng, Xu Zongxiang, Roy, V. A. L., Che Chiming, Lai, P. T., Department of Chemistry and HKU-CAS Joint Laboratory on New Materials, University of Hong Kong, Pokfulam Road, Hong Kong, and Department of Electrical and Electronic Engineering, University of Hong Kong, Pokfulam Road, Hong Kong. Thu . "Method for measurement of the density of thin films of small organic molecules". United States. doi:10.1063/1.2712932.
@article{osti_20953395,
title = {Method for measurement of the density of thin films of small organic molecules},
author = {Xiang Haifeng and Xu Zongxiang and Roy, V. A. L. and Che Chiming and Lai, P. T. and Department of Chemistry and HKU-CAS Joint Laboratory on New Materials, University of Hong Kong, Pokfulam Road, Hong Kong and Department of Electrical and Electronic Engineering, University of Hong Kong, Pokfulam Road, Hong Kong},
abstractNote = {An accurate and sensitive method is reported to measure the thin-film density of vacuum-deposited, small-molecular organic semiconductor materials. A spectrophotometer and surface profiler had been used to determine the mass and thickness of organic thin film, respectively. The calculated density of tris-(8-hydroxyquinolato) aluminum (Alq{sub 3}) thin film was 1.31{+-}0.01 g/cm{sup 3}. Vacuum pressures and thin-film growth rates are found to have less impact on the thin-film density of organic material. However, the thin-film density of organic material strongly depends on its chemical structure and molecular weight. Specifically, the chemical structure determines the density of organic material that affects the molecular volume and intermolecular stacking.},
doi = {10.1063/1.2712932},
journal = {Review of Scientific Instruments},
number = 3,
volume = 78,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}
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