The manufacture of semiconductor components based on gallium nitride (GaN) is currently undergoing a major expansion. This material, by his physical and chemical attractive properties, is a very good candidate for the manufacture of high power and hign frequency operating components. In practice, before integrating these components in an electronic system, the analysis of reliability is a necessary step to validate the used manufacturing technology. The objective of this work is to determine physical mechanisms responsible for the performance degradation of high electron mobility transistors (HEMT) based on AlGaN/GaN and AlInN/GaN heterostructures. At first, the static characterization of the components, by current and capacitance measurements at different temperatures, allowed us to identify anomalies in the characteristics. This non-ideality due to thermal effects seem to come from the trapping mechanisms of carriers by defects in the material. In order to analyze these mechanisms, deep levels transient spectroscopy measurements(DLTS) were carried out on the Schottky contact of the gate. The next step was to measure the deep traps in HEMTs by DLTS on drain current, in order to identify defects directly related to the current in these devices. This study was performed on different components with different geometries to analyze the behavior of these traps. The study of the gate contact is an important step in determining the origin of component failure. For this, we conducted a deep study on different transport mechanisms across the metal/semiconductor barrier. This study allowed us to conclude on the stability of the gate contact after the accelerated aging tests.
