Search results for " HfO2"
showing 3 items of 3 documents
Synergistic Use of Electrochemical Impedance Spectroscopy and Photoelectrochemical Measurements for Studying Solid State Properties of Anodic HfO2
2017
Within the past years, intense research has been carried out on HfO2 as high k material, promising candidate to replace SiO2 as gate dielectric in CMOS based devices (1), and as metal oxide for resistive random access memory (ReRAM) (2). For both technological applications compact, uniform and flat oxides are necessary, and a detailed understanding of their physical properties as a function of the fabrication conditions is strongly. Hafnia performance can be significantly influenced by carrier trapping taking place at pre-existing precursors states (induced by oxygen vacancies, interstitial ions, impurities acting as dopants), or by self-trapping in a perfect lattice, where the potential we…
The Effect of Nb Incorporation on the Electronic Properties of Anodic HfO2
2017
Hafnium oxide and Nb doped HfO2 were grown by anodizing sputtering-deposited Hf and Hf-4at.%Nb. Photoelectrochemical characterization was carried out in order to estimate solid state properties such as band gap, flat band potential and electrons internal photoemission threshold energy as a function of thickness and composition of anodic oxides. Optical transitions at energy lower than the band gap value of the investigated anodic films were evidenced, and they are attributed to optical transitions involving localized states inside the band gap. Such states were located at 3.6 eV and 3.9 eV below the conduction band edge for the Nb free and Nb containing hafnium oxide, respectively. Impedanc…
Fabrication and characterization of microscale HfO2-based Memristors
2017
Memristors are metal/insulator/metal devices whose resistance can be switched between two different states (i.e. the low resistive state LRS, and the high resistive state, HRS) by applying a proper voltage value over the two metal contacts [1], [2]. Their simple structure makes memristors prone to extreme down scaling and 3-D stacking potentiality, and excellent compatibility with the complementary metal-oxide-semiconductor (CMOS) technology. Moreover, because of their low power consumption and high speed, memristors are rightly considered the elemental bricks for a next generation of high-density nonvolatile memories. HfO2 has attracted much attention as an oxide material for memristor app…