Study on Stabilizing Cubic HfO2 Doped Y2O3 using Transmission Electron Microscopy

Traditionally, the most common gate insulator used in transistors is Silicon Dioxide or SiO 2 ; however, as transistors are made smaller and smaller a breaking point has been reached such that SiO 2  no longer acts as an insulator. For this reason, in order to continue improving transistor density, a material or a combination of materials must replace or be added to SiO 2  as a gate insulator. HfO 2 seems to be a promising candidate due to its higher dielectric constant compared to Si 2  and large band gap. Furthermore, by doping this HfO 2  with Yttrium Oxide or Y 2 O 3 , the structural transformation from the monoclinic to the cubic phase is possible, consequently maintaining a higher dielectric constant. Several different samples of HfO 2  with varying concentrations of Y 2 O 3  were studied using a Transmission Electron Microscope (TEM) in order to analyze the structure alterations at various temperatures.