In situ atomic force microscopy studies on lithium (de)intercalation-induced morphology changes in LixCoO2 micro-machined thin film electrodes

Thin film electronic devices that employ resistance change responses of Pt / Ti films to detect gas species have been microfabricated at the University of Michigan. Atomic force microscopy (AFM) is used to investigate morphology of the Pt / Ti sensing films deposited on the microfabricated device. These Pt / Ti sensing films are strongly influenced by many factors, making it difficult to determine the exact relationship between film structure, chemical sensitivity, and selectivity. In-situ AFM investigations of Pt / Ti films on this device at elevated temperatures provides the opportunity for real time observation of film morphology changes under controlled conditions, testing sensing film stability during device operation, and correlating film structure to resistance.Observation of the Pt / Ti film surface and in-situ resistance measurements at elevated temperatures are possible due to the construction of the sensing device. The sensors are based on chemically active thin films deposited on a micromachined silicon window, supported by a 300 μn thick silicon rim.

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Crystal Growth in Poly(L-lactide) Thin Film Revealed by in situ Atomic Force Microscopy

Macromolecular Chemistry and Physics ◽

10.1002/macp.200350044 ◽

2003 ◽

Vol 204 (15) ◽

pp. 1822-1831 ◽

Cited By ~ 50

Author(s):

Yoshihiro Kikkawa ◽

Hideki Abe ◽

Masahiro Fujita ◽

Tadahisa Iwata ◽

Yoshio Inoue ◽

...

Keyword(s):

Thin Film ◽

Atomic Force Microscopy ◽

Crystal Growth ◽

Force Microscopy ◽

Atomic Force

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Measuring Thickness Changes in Thin Films Due to Chemical Reaction by Monitoring the Surface Roughness with In Situ Atomic Force Microscopy

Microscopy and Microanalysis ◽

10.1017/s1431927602010309 ◽

2002 ◽

Vol 8 (5) ◽

pp. 422-428 ◽

Cited By ~ 25

Author(s):

L.Y. Beaulieu ◽

A.D. Rutenberg ◽

J.R. Dahn

Keyword(s):

Thin Film ◽

Thin Films ◽

Surface Roughness ◽

Atomic Force Microscopy ◽

Alloy Film ◽

Force Microscopy ◽

Atomic Force ◽

Direct Proportionality ◽

Roughness Measurements

Measuring the changing thickness of a thin film, without a reference, using an atomic force microscope (AFM) is problematic. Here, we report a method for measuring film thickness based on in situ monitoring of surface roughness of films as their thickness changes. For example, in situ AFM roughness measurements have been performed on alloy film electrodes on rigid substrates as they react with lithium electrochemically. The addition (or removal) of lithium to (or from) the alloy causes the latter to expand (or contract) reversibly in the direction perpendicular to the substrate and, in principle, the change in the overall height of these materials is directly proportional to the change in roughness. If the substrate on which the film is deposited is not perfectly smooth, a correction to the direct proportionality is needed and this is also discussed.

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