Recent Advances in Gate Dielectrics for Enhanced Leakage Current Management and Device Performance

Gate oxide in metal oxide semiconductor field effect transistor (MOSFET) or gate dielectric layer in thin film transistor (TFT) plays an important role in the inhibition of leakage current. Thus, high-quality of insulating properties (> 10 MV/cm) and high resistance of gate dielectric have been required. The dimension of gate oxide needs to be reduced for the amplified on-current and switching speed. However, the dimension of the oxide, developed so far, has reached its limit, and leakage current is inevitable. The structural, processing, and material methods were categorically discussed to improve insulating properties in TFT and MOSFET for leakage reduction. The parameters including threshold voltage, subthreshold swing (SS), and off current of developed devices were compared in this paper. Through advanced structure application such as GAA, capacitorless DRAM, and hybrid dielectrics, MOSFETs could be scaled down with minimum leakage current. This review paper has been divided into sections covering structural, material, and process developments that have been researched to date. After briefly explaining each of these aspects, the paper concludes by proposing the application of NO precursor as a novel reactant material, deuterium-passivation, and process parameter optimization to address the current reduction for further research.