Research Progress of High Dielectric Constant Zirconia-Based Materials for Gate Dielectric Application

Abstract

The high dielectric constant ZrO2, as one of the most promising gate dielectric materials for next generation semiconductor device, is expected to be introduced as a new high k dielectric layer to replace the traditional SiO2 gate dielectric. The electrical properties of ZrO2 films prepared by various deposition methods and the main methods to improve their electrical properties are introduced, including doping of nonmetal elements, metal doping design of pseudo-binary alloy system, new stacking structure, coupling with organic materials and utilization of crystalline ZrO2 as well as optimization of low-temperature solution process. The applications of ZrO2 and its composite thin film materials in metal oxide semiconductor field effect transistor (MOSFET) and thin film transistors (TFTs) with low power consumption and high performance are prospected.

Structure and Electrical Properties of Zirconium-Aluminum-Oxide Films Engineered by Atomic Layer Deposition

“…Nonetheless, it has been concluded earlier that the average k of disordered ZrO 2 as high as 22.2 can be considered [53]. Such permittivity values for crystalline and disordered ZrO 2 have been supported by a number of experimental studies and may be regarded as reference values for ZrO 2 films synthesized by various methods [54].…”

“…In regard with the literature reporting the capacitive parameters of ZrO 2 -based thin films, a reader could attend a recent review paper by Xie et al [54] and references therein. The results reported to date allow one to conclude that the permittivity of capacitive ZrO 2based cells can vary between 7 and 37, depending on the processing parameters, thickness, structural order, and dopant metal in ZrO 2 , together with the electrode materials selected to complete the cell structure.…”

Gd3+ and Bi3+ co-substituted cubic zirconia; (Zr1−x−yGdxBiyO2−δ): a novel high κ relaxor dielectric and superior oxide-ion conductor

“…Relaxor type of high dielectric materials were also reported for doped cubic zirconia phases. [41][42][43][44] We have envisaged that high polarizability of Bi 3+ ion couple with high k dielectric relaxation (high dielectric leakage) can generate superior oxide-ion conduction near T m (the temperature of the maximum dielectric permittivity). To realize the concept, we attempted the suitable dopping of Bi 3+ and Gd 3+ ions into ZrO 2 lattice to stabilize cubic phase of zirconia and found that the synergistic interaction by introducing a secondary substituent (Gd 3+ ions) enhances the oxide-ion vacancy transport within the percolation limit of ion transport inside the host structure at lower temperatures.…”

High-k materials based on SrHfO3 and BaHfO3: A Hybrid Density Functional Theory Study

“…The typical high-k materials with a large band gap are ZrO 2 and HfO 2 . 6,7 Several studies have shown that preferably the band gap for a high-k material should be above ~ 5 eV.…”