Overview >> Theory - Ab initio investigation of dielectrics for modern microelectronics
| The Objective | SiO2 gate dielectrics in MOS transistors and MIM capacitors have approached the limit of viable thicknesses. To answer some of the key questions appearing in this context one needs insight into atomic processes during dielectric formation and operation. We address these questions by ab initio calculations. Two groups of problems here are of major practical interest: defect chemistry and band structures. Point defects and their complexes are responsible for leakages across the MOS structure, that is, for power losses. They also deteriorate MOSFET parameters, e.g., charged defects shift the threshold voltage and interfacial states reduce the switching speed. These defects must be identified and methods to reduce their concentration must be found. Band gaps and band offsets are the other crucial factor determining the MOS leakage. We address these issues primarily for Pr-based dielectrics (oxides, silicates, and aluminates). more |
| IHP’s Contribution | Project coordination and total energy calculations. |
| Funding | Supercomputer time grant from von Neumann Institute for Computing |
| Project Partners | IHP, TU Würzburg |