Conductivity modulated on-axis 4H-SiC 10+ kV PiN diodes

Abstract

Degradation-free ultrahigh-voltage (>10 kV) PiN diodes using on-axis 4H-SiC with low forward voltage drop (V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">F</sub> = 3.3 V at 100 A/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> ) and low differential on-resistance (R <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ON</sub> = 3.4 mΩ.cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> ) are fabricated, measured, and analyzed by device simulation. The devices show stable on-state characteristics over a broad temperature range up to 300 °C. They show no breakdown up to 10 kV, i.e., the highest blocking capability for 4H-SiC devices using on-axis to date. The minority carrier lifetime (τ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">P</sub> ) is measured after epitaxial growth by time resolved photoluminescence (TRPL) technique at room temperature. The τ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">P</sub> is measured again after device fabrication by open circuit voltage decay (OCVD) up to 500 K.