A high current density SOI-LIGBT with Segmented Trenches in the Anode region for suppressing negative differential resistance regime

Abstract

A SOI-LIGBT with Segmented Trenches in the Anode region (STA-LIGBT) is proposed and compared with the separated shorted-anode LIGBT (SSA-LIGBT) for the first time. The proposed STA-LIGBT structure features that there are segmented trenches located between the P <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">+</sup> anode and the segmented N <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">+</sup> anodes. By employing the segmented trenches, the resistance between the P <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">+</sup> anode and the shorted N <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">+</sup> anode is significantly increased, which effectively suppresses the negative differential resistance (NDR). The experiments show that the STA-LIGBT with its blocking voltage of 540V can achieve a current density (J <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">C</sub> ) of 247 A/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> when the gate voltage is 10V and the anode voltage is 3V. With the same the NDR regime (the snapback voltage is 1.3V), the current density (J <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">C</sub> ) of the STA-LIGBT is about 170% of that of the SSA-LIGBT. The fabrication of the segmented trenches is compatible with the trench isolation process and no extra or complicated processes are needed.