Institute of High Pressure Physics

The review paper by Stanisław Krukowski, Paweł Kempisty and Paweł Strak, entitled "Charge control of semiconductor surfaces as elucidated by ab initio calculations – A review" has just been published in Progress in Surface Science 101(1), 100809 (2026), https://doi.org/10.1016/j.progsurf.2025.100809.

The paper reviews 15 years of research progress on the role of electric charge at semiconductor surfaces, highlighting how this work has contributed to the development of new scientific concepts in the field. Notably, much of the advancement stems from the conceptual, computational, and analytical efforts of scientists at IHPP PAS. Congratulations to the team, and we encourage readers to explore this review article.

The review incorporates new methods and new physical phenomena:

1. computational methods: Laplace correction – removal of the spurious interaction of slab copies induced by periodic boundary conditions
2. electrical control of the system: pinning of the Fermi level at both surfaces of the slab – emergence of the electric field in the slab
3. data analysis: projected density of states (PDOS) - electric potential distribution  in the slab
4. data analysis: Crystal orbital Hamilton population (COHP) – identification of chemical bonds in the system
5. Separation of quantum subsystems in adsorption modeling – identification of  spurious charge transfer between the isolated quantum subsystems in ab initio methods
6. contribution of the charge transfer between quantum states to adsorption energy – pinning of Fermi level at the semiconductor surface
7. internal surface dipole layer - bending of bands
8. external surface dipole layer – work function
9. adsorbate thermalization (adsorbate kinetic energy loss) – tunneling of electrons from the adsorbate into the crystal
10. charge redistribution at the surface (electron counting rule - ECR) - determination of the period of reconstruction of the semiconductors surfaces
11. role of quantum statistics in the classical diffusion – the influence of the Fermi level on the energies of equilibrium and transition states, i.e. the height of barriers to diffusion
12. resonant bonding - explanation of the band structure of nitrides and its relationship to the crystal lattice symmetry
13. contribution of vibration energy to the free energy of the adsorbate – temperature dependence of the free energy of the adsorbate
14. determination of thermodynamically stable adsorbate coverages of the semiconductor surfaces – chemical potentials of adsorbate and gas phase
15. determination of band profiles in 2-D systems of electron gas (2DEG) in GaN/AlN polar interface systems – determination of the electron charge location using ab initio methods.

Figure: DOS profile in space for various pseudohydrogen atoms used to passivate both the nitrogen side of GaN and the aluminum side of the AlN side of the GaN/AlN weak surface: (a) Z_N = 0.733 and Z_Al = 1.260, (b) ZN = 0.733 and Z_Al = 1.380. Reprint from Fig. 3 [S. Zoino, L. Borowik, B. Mohamad, E. Nowak, P. Kempisty, Ab initio investigations of two-dimensional gas at interfaces in GaN/AlN and GaN/AlN/Al2O3 heterostructures,  J. Appl. Phys., 134 (2023), Article 155304, 10.1063/5.0169332]., J. Appl. Phys., 134 (2023), 55304, 10.1063/5.0169332].