MA: Simulation of a three-zone furnace for ammonothermal crystal growth

21. Oktober 2025

Bearbeiter

Jun Zheng

Art der Arbeit

Masterarbeit

Beschreibung

Nitride semiconductors as semiconductors with a large band gap are playing an increasingly important role as substrate material for power electronic devices. Ammonothermal crystal growth is a promising growth method for a wide variety of nitride semiconductor materials. The advantage of this method is the ability to produce crystals with very high structural quality and the scalability due to the simultaneous growth of several crystals.
In crystal growth, technology development plays a crucial role for the process development, to obtain crystals of higher quality (crystalline perfection, purity, etc.). One key technology in this field is modelling and simulation of the growth furnace to understand the key parameters for controlling the thermal field. This allows for a targeted optimization of the furnace construction as well as the operating parameters during the crystal growth.
In this work, a model will be created for a novel concept of a three-zone furnace for ammonothermal crystal growth, including the thermal surroundings of the furnace. The model will be validated with reference measurements obtained by experiments using the novel three-zone furnace, focusing on the temperature distribution along the outer wall of the autoclave. Deviations between the experimentally obtained data and the simulation results will be evaluated, aiming for an understanding of their causes. The model will be adapted if necessary. The model will then be used to identify the key parameters of the setup and to verify the weaknesses and strengths of the concept. The next step is to optimize the control variables and to derive possible new steps in the technology development towards improved growth conditions.