Wide-Bandgap Device Physics

Why wide-bandgap semiconductors?

Wide-bandgap semiconductors can operate under electric fields, temperatures and radiation environments that are challenging for conventional silicon devices. Their properties make them promising for compact radiation detectors and robust electronic systems.

My work focuses principally on 4H-SiC and GaN, examining how their physical advantages appear—and sometimes fail to appear—at the device level.

4H-SiC

4H-SiC combines a wide bandgap, high critical electric field, good thermal conductivity and strong radiation tolerance. These properties make it attractive for low-leakage detectors, high-voltage junctions and radiation-sensing structures.

• Uniform electric-field distribution
• Junction and contact structures that suppress leakage and delay breakdown
• Effects of thickness, doping and geometry on charge collection
• Balancing radiation interaction probability with signal formation

GaN

GaN offers a wide bandgap, high breakdown field and access to heterostructure physics, including high-mobility two-dimensional electron-gas channels. It provides a complementary platform for radiation-aware devices and alternative signal-collection concepts.

The work considers junction-based structures and heterostructure-inspired approaches, emphasizing the connection between electrostatics and measurable response.

Device-physics themes

• Junctions and depletion: how doping, compensation and bias define the active volume
• Electric-field engineering: reducing field crowding near contacts, corners and interfaces
• Contacts and interfaces: Schottky, ohmic and insulated-gate boundary conditions
• Charge and signal formation: interpreting both electric field and weighting potential

Open-notebook scope

Future notes will explain selected structures, material parameters and simulation results at a level useful to students and researchers. Public descriptions will remain centred on established physics and published work.