Résumé
The effect of pressure on electrical transport phenomena has been studied in AlGaN/GaN heterostructures grown on Si substrates. The two-dimensional character of the conducting carriers has been verified with high magnetic field measurements (up to 13 T) at low temperature (T = 1.5 K). The two-dimensional electron gas (2DEG) concentration and mobility were measured as a function of hydrostatic pressure up to 1100 MPa and at different temperatures. The observed pressure changes of the free carrier concentration have been compared with theoretical predictions, taking into account the polarization change in the nitrides and using a fully self-consistent resolution of Schrodinger and Poisson equations.