Presentation Information
[1P42]Particle Swarm Optimization Search for Band Bending Potential Shapes that Satisfy Si(001) Valence Electron Subband Levels.
*Mamiko Miyashita1, Taichi Ono1, Ryota Ichikawa1, Brain Godwin Lim1, Tan Renzo Roel1, Kazushi Ikeda1, Ryu Yukawa2, Kazuki Sakamoto3, Sakura Takeda1 (1. Nara Institute of Science and Technology, 2. Tohoku University, 3. Osaka University)
Understanding the quantized electron states within semiconductor space-charge layers is critical for nanodevice performance. Since first-principles calculations are computationally intensive, we developed an experimental data-driven approach to determine the band-bending potential of a Si(001) surface. Our model used a 7-parameter band-bending potential, consisting of a quadratic curve with a perturbation term, as a trial function. Using Particle Swarm Optimization (PSO), we minimized the error between the eigenvalues calculated from our model and experimentally measured Si(001) valence subband levels. While a simple quadratic model failed to accurately reproduce the data, our perturbed potential precisely matched the experimental measurements, revealing a significant deviation from the quadratic shape near the surface. This deviation directly indicates a significant increase in local charge density, suggesting dopant (Arsenic) segregation and a non-uniform impurity distribution.