PhD defense of Kyunghwa LEE

Abstarct:
Fully Depleted SOI (FD-SOI) is an excellent alternative of conventional Complementary Metal Oxide Semiconductor (CMOS) technology which is leading the semiconductor industry. FD-SOI offers low-power consumption and improved electrostatic control for MOS transistors even in very advanced nodes (14 nm and 28 nm). FD-SOI transistors feature nanometer thickness and length which bring rather particular operation mechanisms and characteristics. This work describes the state-of-the-art and assets of FD-SOI components. The Hocus-Pocus (HP) diode is one example of the innovative devices made possible by the unrivaled flexibility of FD-SOI technology. By modifying the type of electrostatic doping, N or P, a single device can be reconfigured as a virtual P-N diode, a virtual Esaki diode, a semi-virtual diode, a P-I-N diode, a TFET or a band-modulation FET. Each configuration works as a physically doped device with peculiar behavior induced by the dynamic change of doping concentration.
Original applications such as lifetime extraction and virtual Esaki diode are explored. The Z2-FET (Zero subthreshold slope and Zero impact ionization) is a striking application of HP diode thanks to attractive characteristics (sharp switch, low leakage current, adjustable triggering voltage and high current ratio ION/IOFF). In this work, we focus on a capacitorless Dynamic Random Access Memory (1T-DRAM) and a fast logic switch.
The DC and transient operation mechanisms as well as the device performance are investigated in detail with TCAD simulations and validated with systematic experimental results.

Jury members:

• Olivier BONNAUD - Reviewer
• Ray HUETING - Reviewer
• Gérard GHIBAUDO - Examiner
• Carlos SAMPEDRO - Examiner