Breaking the theoretical limits of silicon with innovative switch technologies

New semiconductors materials like silicon carbide (SiC) and gallium nitride (GaN) offer as major benefits the possibility of constructing high-voltage switching devices characterized by very low conduction and switching losses. Most of the related research and development has nevertheless been focused on voltage classes like 600V and 1200V. For the referred levels it is expected that such new devices will substitute their Si counterparts in applications like SMPS and renewable power conversion. However, recent developments in Si switches stand in direct concurrence with such prospect. Examples are the Super-junction MOSFETs and ESBTs (emitter-switched bipolar transistor), which stretch the theoretical limits of the Si material and provide very interesting and cost-effective solutions for the referred voltage levels. This paper will firstly provide a brief overview on the characteristics of semiconductor materials, identifying possible target-applications. Afterwards, focus will be given to the referred new Si devices, investigating their features and practical implementation. The obtained information will then be employed to identify not only the actual achievable limits with Si but also to trace the borderline from which SiC or GaN semiconductors may be more effectively employed.