Deterministic simulation of electron and phonon transport in III-V devices
Leading-edge III-V semiconductor devices are pushing electronics to higher frequencies such that they can be used, for example, in safety applications like near field radar for cars or in high speed data transmission. These extremely fast devices with transit and maximum oscillation frequencies beyond 300GHz can be no longer modeled with classical Technology Computer Aided Design (TCAD) tools and more fundamental simulation approaches based on the Boltzmann equation are required. Since electron transport and due to self-heating, which degrades the device performace, phonon transport are of importance in these devices, Boltzmann equations have to be solved for both types of particles in a self-consistent manner. This requires a numerical approach, which goes beyond the possibilities of the state-of-the-art Monte Carlo simulators. Recently a deterministic Boltzmann equation solver has been developed for silicon devices, which has all the required TCAD features and can simulate the stationary and small-signal device characteristics and electronic noise. This simulator will be extended to III-V materials including phonons.
The main focus of the project will be on the development of the thermal part of the simulator, which will be based on a spherical harmonics expansion like the electron part. In order to use the simulator in a design process, it must be numerically stable and efficient. The newly developed simulator will be used to investigate real devices, for which the measurement data will be provided by a partner, and to explore the ultimate limits of III-V devices.