A High-Accuracy AlGaN/GaN Reverse Blocking CRD (RB-CRD) with Hybrid Trench Cathode

Area of Science:

• Materials Science
• Electrical Engineering
• Semiconductor Physics

Background:

• Gallium Nitride (GaN) based devices are crucial for high-power and high-frequency applications due to their superior material properties.
• Current regulating diodes (CRDs) are essential components for stabilizing current in electronic circuits, particularly under varying conditions.
• Lateral device structures offer advantages in scalability and integration for advanced semiconductor applications.

Purpose of the Study:

• To propose and experimentally demonstrate a novel AlGaN/GaN lateral reverse blocking current regulating diode (RB-CRD).
• To integrate a Schottky barrier diode (SBD) anode with a hybrid trench cathode for enhanced current regulation.
• To evaluate the performance characteristics, including voltage ratings and temperature stability, of the proposed RB-CRD.

Main Methods:

• Fabrication of an AlGaN/GaN lateral RB-CRD on a silicon substrate utilizing trench technology for both anode and cathode.
• Integration of a Schottky barrier diode (SBD) in the anode structure to achieve reverse blocking capability.
• Characterization of the device's electrical performance, including turn-on voltage, reverse breakdown voltage, knee voltage, and forward operating voltage.
• Testing of the RB-CRD's current regulating capability and temperature stability over a wide operational range (25°C to 300°C).

Main Results:

• The integrated SBD anode demonstrated a turn-on voltage of 0.7 V and a reverse breakdown voltage of 260 V.
• The hybrid trench cathode functioned as a CRD, enabling a knee voltage of 1.3 V and forward operation beyond 200 V.
• The RB-CRD exhibited excellent steady current output across temperatures from 25°C to 300°C.
• The forward regulating current showed small negative temperature coefficients, less than -0.152%/°C.

Conclusions:

• The proposed AlGaN/GaN lateral RB-CRD with trench Schottky anode and hybrid trench cathode is experimentally validated.
• The device offers robust current regulation with high voltage ratings and exceptional stability over an extensive temperature range.
• This novel RB-CRD presents a promising solution for stable current delivery in demanding power electronic applications.