Quantum Channel Extreme Bandgap AlGaN HEMT

Area of Science:

• Materials Science
• Condensed Matter Physics
• Semiconductor Device Physics

Background:

• Conventional high-electron-mobility transistors (HEMTs) face limitations in breakdown voltage.
• The design of the quantum channel in HEMTs is crucial for device performance.
• AlGaN-based materials offer potential for high-power applications due to their wide bandgap properties.

Purpose of the Study:

• To investigate the impact of a quantum channel design on the breakdown field of AlGaN HEMTs.
• To understand the role of electron quantization and polarization fields in enhancing device performance.
• To demonstrate the potential of quantum channel HEMTs for superior power device applications.

Main Methods:

• Metalorganic Chemical Vapor Deposition (MOCVD) growth of an AlGaN quantum channel HEMT on an AlN substrate.
• Characterization of the critical breakdown field and analysis of electron gas quantization effects.
• Investigation of quantum-enabled real space transfer mechanisms in high electric fields.

Main Results:

• Achieved a critical breakdown field of 11.37 MV/cm, exceeding the expected value for the AlGaN channel material.
• Demonstrated that electron quantization in the 2D electron gas contributes significantly to the increased breakdown field.
• Observed quantum-enabled real space transfer of electrons into barrier layers, further enhancing breakdown voltage.

Conclusions:

• The quantum channel design in AlGaN HEMTs enables enhanced electron confinement and polarization effects, leading to record-high breakdown voltages.
• This approach overcomes limitations of conventional HEMT designs, particularly at low sheet electron densities.
• Quantum channel HEMTs represent a promising pathway for developing next-generation superior power electronic devices.