Electrical properties of ZrO2 gate dielectric on SiGe

Abstract

We report the electrical properties of a high dielectric constant (high-k) material, ZrO2, deposited directly on SiGe, without the use of a Si buffer layer or a passivation barrier. ZrO2 thin films of equivalent oxide thickness (EOT) down to 16.5 Å were deposited on strained SiGe layers by reactive sputtering. Results indicate that ZrO2 films on SiGe have good interfacial properties and low leakage currents. Sintering in forming gas at 350 °C for 1 h could further improve the film quality. Although threshold voltage stability and dielectric dispersion become a concern for thick ZrO2 films, thin ZrO2 films of EOT less than 20 Å exhibit excellent electrical properties making them a good candidate for SiGe applications.

Properties of high k gate dielectric gadolinium oxide deposited on Si (1 0 0) by dual ion beam deposition (DIBD)

“…These requirements include dielectric constant, band gap, band alignment to silicon, low oxygen diffusivity, lower leakage current than SiO 2 at an equivalent oxide thickness (t eq defined as ðk SiO 2 =k oxide Þt phys ) less than 1.5 nm, thermodynamic stability in contact with silicon at temperature exceeding 800 C, high-quality interface with silicon with low interfacial state density [2]. Some binary metal oxides are currently under consideration as the potential replacements for SiO 2 as the gate dielectrics, such as Ta 2 O 5 [3,4], TiO 2 [5], ZrO 2 [6].…”

Fianite in Photonics

“…That requires a change of SiO 2 over dielectrics with higher dielectric constant (high-k materials) [33][34][35]51]. The resent studies have limited possible alternatives to fianite, HfO 2 , ZrO 2 and its silicates.…”

“…In recent years a considerable attention was drawn to fianite films on silicon due to its electric and optic device applications, such as isolating layers in SOI (silicon-on-insulator) devices [32], gate dielectric in Si- [33,34], SiGe- [35] and A III B V -based [36] device structures, buffer layers for producing of optic coatings of films of various semiconductors [37][38][39][40], superconductors [41][42][43], ferroelectrics, etc.…”

Interfacial and Electrical Properties of Ge MOS Capacitor by ZrLaON Passivation Layer and Fluorine Incorporation

“…It is well known that Zirconium dioxide (ZrO 2 ) has a high k value (~ 20), a large bandgap (5.8 eV) and has been used as high-k gate dielectric for Si [8], SiGe [9] and GaAs [10] interfacial and electrical properties. However, ZrO 2 may easily crystallize due to its lower crystallization temperature (400 -500 ℃) [11], thus leading to a large gate leakage current [12].…”