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Updated: May 14, 2026

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Atomically Traceable Nanostructure Fabrication
Published on: July 17, 2015
An atomic layer deposition reactor with dose quantification for precursor adsorption and reactivity studies.
T J Larrabee1, T E Mallouk, D L Allara
1Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, USA.
The Review of Scientific Instruments
|February 8, 2013
Summary
A new atomic layer deposition reactor precisely controls precursor doses for studying adsorption. This enables accurate film growth control by relating gas exposure to fluid dynamics.
Area of Science:
- Materials Science
- Chemical Engineering
- Surface Science
Background:
- Atomic Layer Deposition (ALD) requires precise control over precursor delivery.
- Understanding precursor adsorption is crucial for optimizing ALD processes.
- Current methods may lack quantitative dose control and in situ analysis.
Purpose of the Study:
- To construct an ALD reactor with quantitative, precision dose control.
- To study precursor adsorption characteristics and dynamics.
- To correlate dose quantity and exposure with fluid flow regimes.
Main Methods:
- Utilized computer-controlled pneumatic valves for precise gas dosing.
- Employed dual in situ quartz crystal microbalances for parallel mass measurement.
- Integrated a quadrupole mass spectrometer for in situ gas composition analysis.
Main Results:
- Demonstrated quantitative control over precursor dose amounts.
- Enabled determination of adsorption coverage and relative sticking coefficients.
- Established a method to unambiguously calculate absolute reactant exposure.
Conclusions:
- The developed ALD reactor offers precise control over precursor delivery.
- Quantitative dose control facilitates a deeper understanding of adsorption phenomena.
- This system provides a foundation for advanced film growth control strategies.
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