Modeling the Non-Equilibrium Process of the Chemical Adsorption of Ammonia on GaN(0001) Reconstructed Surfaces Based on Steepest-Entropy-Ascent Quantum Thermodynamics
| dc.contributor.author | Kusaba, Akira | en |
| dc.contributor.author | Li, Guanchen | en |
| dc.contributor.author | von Spakovsky, Michael R. | en |
| dc.contributor.author | Kangawa, Yoshihiro | en |
| dc.contributor.author | Kakimoto, Koichi | en |
| dc.contributor.department | Mechanical Engineering | en |
| dc.date.accessioned | 2017-09-20T18:35:08Z | en |
| dc.date.available | 2017-09-20T18:35:08Z | en |
| dc.date.issued | 2017-08-15 | en |
| dc.date.updated | 2017-09-20T18:35:09Z | en |
| dc.description.abstract | Clearly understanding elementary growth processes that depend on surface reconstruction is essential to controlling vapor-phase epitaxy more precisely. In this study, ammonia chemical adsorption on GaN(0001) reconstructed surfaces under metalorganic vapor phase epitaxy (MOVPE) conditions (3Ga-H and N<sub>ad</sub>-H + Ga-H on a 2 × 2 unit cell) is investigated using steepest-entropy-ascent quantum thermodynamics (SEAQT). SEAQT is a thermodynamic-ensemble based, first-principles framework that can predict the behavior of non-equilibrium processes, even those far from equilibrium where the state evolution is a combination of reversible and irreversible dynamics. SEAQT is an ideal choice to handle this problem on a first-principles basis since the chemical adsorption process starts from a highly non-equilibrium state. A result of the analysis shows that the probability of adsorption on 3Ga-H is significantly higher than that on N<sub>ad</sub>-H + Ga-H. Additionally, the growth temperature dependence of these adsorption probabilities and the temperature increase due to the heat of reaction is determined. The non-equilibrium thermodynamic modeling applied can lead to better control of the MOVPE process through the selection of preferable reconstructed surfaces. The modeling also demonstrates the efficacy of DFT-SEAQT coupling for determining detailed non-equilibrium process characteristics with a much smaller computational burden than would be entailed with mechanics-based, microscopic-mesoscopic approaches. | en |
| dc.description.version | Published version | en |
| dc.format.mimetype | application/pdf | en |
| dc.identifier.citation | Kusaba, A.; Li, G.; von Spakovsky, M.R.; Kangawa, Y.; Kakimoto, K. Modeling the Non-Equilibrium Process of the Chemical Adsorption of Ammonia on GaN(0001) Reconstructed Surfaces Based on Steepest-Entropy-Ascent Quantum Thermodynamics. Materials 2017, 10, 948. | en |
| dc.identifier.doi | https://doi.org/10.3390/ma10080948 | en |
| dc.identifier.uri | http://hdl.handle.net/10919/79351 | en |
| dc.language.iso | en | en |
| dc.publisher | MDPI | en |
| dc.rights | Creative Commons Attribution 4.0 International | en |
| dc.rights.uri | http://creativecommons.org/licenses/by/4.0/ | en |
| dc.subject | metalorganic vapor phase epitaxy | en |
| dc.subject | gallium nitride | en |
| dc.subject | chemical adsorption | en |
| dc.subject | surface reconstruction | en |
| dc.subject | density functional theory calculations | en |
| dc.subject | steepest-entropy-ascent quantum thermodynamics | en |
| dc.title | Modeling the Non-Equilibrium Process of the Chemical Adsorption of Ammonia on GaN(0001) Reconstructed Surfaces Based on Steepest-Entropy-Ascent Quantum Thermodynamics | en |
| dc.title.serial | Materials | en |
| dc.type | Article - Refereed | en |
| dc.type.dcmitype | Text | en |