Power semiconductor devices are utilized in power conversion systems and as drivers for high power optical laser systems. For such devices, a vertical topology is favorable since it combines thick epitaxial layers for blocking high voltage in off-state and very high current density for low resistance during on-state. Moreover, this topology offers low energy consumption and, using the bulk semiconductor, an enhanced thermal dissipation. We made significant progress in exploring and developing vertical transistors based on gallium nitride (GaN) – demonstrating transistor structures with extremely compact dimensions that push the boundaries to what is currently possible.
Very high acquisition-rate long-range LIDAR systems, used for example for autonomous driving, require fast laser driving along with high-power supply electronics. The integration of GaN-based power electronics enables very fast laser drivers with high current densities. Conventional laser assembly architectures do not fulfill these requirements, and thus a new architecture is essential.
We have developed a concept for a chip-on-chip integration of a diode laser with a vertical GaN transistor serving as a fast driver.