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Updated: May 28, 2026
09:45
Monolayer Contact Doping of Silicon Surfaces and Nanowires Using Organophosphorus Compounds
Published on: December 2, 2013
Estimation of phosphorus concentration in doped silicon substrates using atom probe tomography
Jun-Peng Su1, Tung-Huan Chou2, Yu-Chen Yang2
1Department of Materials Science and Engineering, National Yang Ming Chiao Tung University, Hsinchu, Taiwan.
Ultramicroscopy
|May 26, 2026
Summary
Optimizing laser pulse energy in laser-assisted atom probe tomography (APT) is crucial for accurate phosphorus dopant quantification in silicon. Lower energies enhance monomeric phosphorus ions, improving results compared to secondary ion mass spectrometry (SIMS).
Area of Science:
- Materials Science
- Semiconductor Physics
- Analytical Chemistry
Background:
- Accurate dopant quantification is essential for advanced semiconductor device performance.
- Laser-assisted atom probe tomography (APT) is a powerful technique for nanoscale material analysis.
- Phosphorus (P) dopant analysis in silicon presents challenges due to potential ion formation complexities.
Purpose of the Study:
- To investigate the impact of laser pulse energy on phosphorus ion formation during APT analysis.
- To determine the optimal laser energy for accurate phosphorus dopant quantification in silicon.
- To compare APT results with secondary ion mass spectrometry (SIMS) for validation.
Main Methods:
- Utilized laser-assisted atom probe tomography (APT) to analyze phosphorus in silicon.
- Varied laser pulse energy to observe effects on ion formation and spectral data.
- Employed secondary ion mass spectrometry (SIMS) for comparative quantitative analysis.
Main Results:
- High laser energies promote polymeric phosphorus ion (P2+, P3+) formation, causing spectral overlap and quantification errors.
- Reduced laser energy suppresses polymeric ions, favoring monomeric phosphorus ions (P+).
- An optimized laser energy of 5 pJ resulted in >95% monomeric ions, achieving ~1% agreement with SIMS.
Conclusions:
- Laser pulse energy is a critical parameter for accurate phosphorus quantification using APT.
- Optimizing laser energy minimizes polymeric ion interferences, enabling reliable dopant analysis.
- This study provides practical guidelines for precise phosphorus dopant analysis in silicon-based devices using APT.
