2000 Fiscal Year Final Research Report Summary
STUDY OF ORGANIC THIN FILM GROWTH BY MODULATED MOLECULAR BEAM SCATTERING AND SEARCH FOR CATALITIC CONTROL FACTOR
| Project/Area Number |
11650006
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Applied materials science/Crystal engineering
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| Research Institution | The University of Tokyo |
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Principal Investigator |
SHIMADA Toshihiro Univ.Tokyo, School of Science, Lecturer, 大学院・理学系研究科, 講師 (10262148)
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| Project Period (FY) |
1999 – 2000
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| Keywords | molecular beam scattering / organic thin films / crystal growth kinetics / phthalocyanine / Alq3 / C60 / isomer / van der Waals |
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| Research Abstract |
Molecular beam scattering technique for large organic molecules has been developed and used for the study of organic thin film growth. The study aimed at three subject : (i) Precise measurement of van der Waals interaction between organic molecules and inorganic surfaces. (ii) Controlling the kinetics of organic thin film growth by pulsed molecular beams. (iii) Search for catalytic adsorbate which can control the growth kinetics. The following results have been obtained.
(i) Pulsed molecular beams of hydrogen phthalocyanine and C60 were irradiated on various ingoranic materials and surface residence time was obtained. The substrate materials dependence is in the order of ionic>metal>amorphous, which suggests the strength of the interaction between the molecules and the substrates. The reason why the surface residence time is small on the amorphous substrates might be related with the "quantum friction" in which the commensuration of charge distribution between the molecules and the surface is important.
(ii) Pulsed molecular beams were used for organic thin film growth. It was found that the nucleation kinetics at the first stage of the thin film growth can be controlled by changing the width of the pulses. When the molecules have strong anisotropy, the nucleation density can take a minimum as a function of the pulse duration even if the duty ratio is the same. From the theoretical analysis, this finding can be explained by collision induced desorption of the migrating molecules.
(iii) Epiaxial growth of Alq3 was achieved on alkali halide. The isomer has been found to be "mer" by precise analysis of high energy electron diffraction. This molecule can be a candidate for the catalitic control factor for the organic thin film growth.
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