TWO-DIMENSIONAL MATERIALS FOR ADVANCED LOGIC AND MEMORY APPLICATIONS

Abstract

Two-dimensional materials (2DMats) with enhanced electrostatic control, low-thermal budget, and defect-assisted, low-voltage switching capability are garnering interest as logic and memory elements. This thesis investigates two directions to explore 2DMats for future computing applications, namely monolithic 3D (M3D) integration of logic with memory and physical insights into memtransistor—a gate-tunable memristor. Firstly, a hybrid co-integration of tungsten diselenide (WSe2)-based one-transistor one-resistor (1T1R) memory cell is investigated for M3D technology. While a plasma oxidation technique is developed to boost the transistor drive performance by 100x, a solution-processed WSe2 is utilized for low-power resistive memories. Furthermore, channel stacking is proposed for realizing high-density 1T1R memory cells. Lastly, a self-consistent physical model is developed for memtransistor using non-linear equations for lattice temperature, vacancy dynamics, and channel electrostatics. The findings related to the contribution of threshold voltage shifts on resistive switching and self-heating on the memory reset operation are expected to guide future device designs.