Strategies for CMOS Low Equivalent Oxide Thickness Achievement with High-κ Oxides Grown on Si(001) by MBE

2008 ◽  
Vol 1073 ◽  
Author(s):  
Loic Becerra ◽  
Clément Merckling ◽  
Nicolas Baboux ◽  
Mario El-Kazzi ◽  
Guillaume Saint-Girons ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Molecular Beam ◽  
Oxide Thickness ◽  
Flat Band ◽  
Equivalent Oxide Thickness ◽  
Electrical Measurements ◽  
X Ray ◽  
High K ◽  
Density Of Interface States ◽  
Post Deposition

ABSTRACTAmorphous LaAlO3 high-k oxide was grown in a molecular beam epitaxy reactor on p-Si(001) using a thin γ-Al2O3 epitaxied buffer layer. Interfaces were free of SiO2 or silicates and remained abrupt despite the high temperature used for annealing, as X-ray photoelectron spectroscopy showed. Electrical measurements performed on as-deposited samples revealed a dielectric constant value close to that of the bulk, small equivalent oxide thickness and low density of interface states. But some negative charges were present, leading to a flat band voltage shift. Post deposition annealing with forming gas can correct this effect.

Electrical Characteristics of Crystalline Gd2O3 Film on Si (111): Impacts of Growth Temperature and Post Deposition Annealing

2010 ◽  
Vol 1252 ◽  
Author(s):  
Gang Niu ◽  
Bertrand Vilquin ◽  
Nicolas Baboux ◽  
Guillaume Saint-Girons ◽  
Carole Plossu ◽  
...  
Keyword(s):  
Molecular Beam ◽  
Defect Density ◽  
Oxide Thickness ◽  
Electrical Characteristics ◽  
Equivalent Oxide Thickness ◽  
Optimal Temperature ◽  
Post Deposition Annealing ◽  
High K ◽  
Electrical Characterizations ◽  
Post Deposition

AbstractThis work reports on the epitaxial growth of crystalline high-k Gd2O3 on Si (111) by Molecular Beam Epitaxy (MBE) for CMOS gate application. Epitaxial Gd2O3 films of different thicknesses have been deposited on Si (111) between 650°C~750°C. Electrical characterizations reveal that the sample grown at the optimal temperature (700°C) presents an equivalent oxide thickness (EOT) of 0.73nm with a leakage current density of 3.6×10-2 A/cm2 at |Vg-VFB|=1V. Different Post deposition Annealing (PDA) treatments have been performed for the samples grown under optimal condition. The Gd2O3 films exhibit good stability and the PDA process can effectively reduce the defect density in the oxide layer, which results in higher performances of the Gd2O3/Si (111) capacitor.

Growth and Properties of Gadolinium Oxide Dielectric Layers on Silicon Carbide for High-K Application

2007 ◽  
Vol 556-557 ◽  
pp. 655-658 ◽  
Author(s):  
Andreas Fissel ◽  
M. Czernohorsky ◽  
R. Dagris ◽  
H.J. Osten
Keyword(s):  
Photoelectron Spectroscopy ◽  
Gadolinium Oxide ◽  
Flat Band ◽  
Growth Interface ◽  
X Ray ◽  
Fixed Charges ◽  
High K ◽  
Structural And Electrical Properties ◽  
Cv Measurements ◽  
Oriented Layers

We investigated the growth, interface formation as well as the structural and electrical properties of crystalline gadolinium oxide (Gd2O3) directly grown on 6H-SiC(0001) substrates by molecular beam epitaxy. The Gd2O3 layers were found to grow epitaxially resulting in the formation of flat (111) oriented layers with the cubic bixbyite type of structure. X-ray photoelectron spectroscopy measurements reveal a silicate-like Gd2O3/SiC interface. Furthermore, conduction and valence band discontinuities at the Gd2O3/6H-SiC interface were estimated with 1.9 eV and 1.2 eV, respectively. The fabricated capacitors exhibit suitable dielectric properties at room temperature; such as a dielectric constant of ε = 22, a leakage current of 10-8 A/cm2@1V and breakdown fields > 4.3 MV/cm for layers with 14 nm thickness. The CV measurements exhibit only small negative flat band shifts and a very small hysteresis, resulting from fixed charges or interface trap levels in the range of 1x1012 cm-2. These properties make Gd2O3 suitable for high-k application also for SiC.

Interface Engineering During Epitaxial Growth of High-K Lanthanide Oxides on Silicon

2006 ◽  
Vol 917 ◽  
Author(s):  
H. Joerg Osten ◽  
Malte Czernohorsky ◽  
Eberhard Bugiel ◽  
Dirk Kuehne ◽  
Andreas Fissel
Keyword(s):  
Molecular Beam ◽  
Oxygen Supply ◽  
Oxide Thickness ◽  
Interface Structure ◽  
Equivalent Oxide Thickness ◽  
Lanthanide Oxides ◽  
Partial Pressures ◽  
High K ◽  
Current Densities ◽  
Optimized Conditions

AbstractWe investigated the influence of additional oxygen supply and temperature during the growth of thin Gd2O3 layers on Si(001) with molecular beam epitaxy. Additional oxygen supply during growth improves the dielectric properties significantly; however too high oxygen partial pressures lead to an increase in the lower permittivity interfacial layer thickness. The growth temperature mainly influences the dielectric gate stack properties due to changes of the Gd2O3/Si interface structure. Optimized conditions (600 °C, pO2 = 5·10-7 mbar) were found to achieve equivalent oxide thickness values below 1 nm accompanied by leakage current densities below 1 mA/cm2 at 1 V.

Effect of Systematic Changes of Ti and Hf Si-oxynitride Alloys by Nitrogen Incorporation as a Bond Constraint on Electrical and Material Properties

2007 ◽  
Vol 996 ◽  
Author(s):  
Sanghyun Lee ◽  
Gerry Lucovsky ◽  
L. B. Fleming ◽  
Jan Luning
Keyword(s):  
Photoelectron Spectroscopy ◽  
Oxide Thickness ◽  
Ternary Alloys ◽  
Flat Band ◽  
Compositional Dependence ◽  
X Ray ◽  
State Splitting ◽  
Current Voltage ◽  
Current Voltage Characteristics ◽  
X Ray Absorption

AbstractWe have investigated the effect of Si3N4 content in (Ti(Hf)O2)x(Si3N4)y(SiO2)1-x-y pseudo-ternary alloys by tracking systematic changes of electrical properties, including electrically active defects. Results from Soft x-ray photoelectron spectroscopy (SXPS) studies indicate no detectable hole traps for Ti/Hf Si oxynitrides with Si3N4 content >35%; these alloys have equal concentrations of Ti(Hf)O2 and SiO2, ~30-32%, and additionally are stable for annealing in Ar ambients to temperatures of 1100°C. Derivative near edge x-ray absorption spectroscopy (NEXAS) comparisons for the O K1 edges of TiO2 and optimized Ti Si oxynitride alloys provides a significantly reduced average crystal field d-state splitting from 1.9 to 1.6eV, as well as decreased electron trapping, and is correlated with a four-fold coordination of Ti in the Ti Si oxynitride alloys. The flat band voltage shift with varying frequency from 10 kHz to 1MHz in these alloys is less than 12 mV and the compositional dependence of current-voltage characteristics on Si3N4 composition results in the lowest leakage current at a Si3N4 content of ~40 % with the smallest equivalent oxide thickness (EOT) as well. Based on these studies, Transition Metal (TM) Si oxynitride alloys are anticipated to yield EOT <1 nm for scaled CMOS devises.

Study on ZrO2 Deposited Directly on Si as an Alternative Gate Dielectric Material

1999 ◽  
Vol 606 ◽  
Author(s):  
Wen-Jie Qi ◽  
Renee Nieh ◽  
Byoung Hun Lee ◽  
Youngjoo Jeon ◽  
Laegu Kang ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Gate Dielectric ◽  
Dielectric Breakdown ◽  
Dielectric Material ◽  
Oxide Thickness ◽  
Amorphous Structure ◽  
Flat Band ◽  
Equivalent Oxide Thickness ◽  
Low Leakage ◽  
Quantum Mechanical Effects

AbstractReactive-magnetron-sputtered ZrO2 thin film has been deposited on Si directly for gate dielectric application. Both structural and electrical properties of the ZrO2 film have been investigated. An amorphous structure for 30Å ZrO2 and a semi-amorphous structure for 200Å ZrO2 have been revealed. The sputtered film shows a good stoichiometry and a good structural stability of ZrO2 based on the X-ray photoelectron spectroscopy and Rutherford backscattering spectroscopy data. Thin equivalent oxide thickness of about 11.5Å was obtained without the consideration of quantum mechanical effects. A low leakage of less than 10−2 A/cm2 at ±1V relative to the flat band voltage was obtained for this 11.5Å equivalent oxide thickness Pt/ZrO2/Si structure. High effective dielectric breakdown and superior reliability properties have been demonstrated for ZrO2 gate dielectric.

Interface and Electrical Properties of Atomic-layer-deposited HfAlO Gate Dielectric for N-channel GaAs MOSFETs

2009 ◽  
Vol 1155 ◽  
Author(s):  
Rahul Suri ◽  
Daniel J Lichtenwalner ◽  
Veena Misra
Keyword(s):  
Electrical Properties ◽  
Photoelectron Spectroscopy ◽  
Gate Dielectric ◽  
Atomic Layer ◽  
Oxide Thickness ◽  
Gate Leakage Current ◽  
X Ray ◽  
Layer Deposition ◽  
Post Deposition ◽  
Gallium Oxides

AbstractThe interface and electrical properties of HfAlO dielectric formed by atomic layer deposition (ALD) on sulfur-passivated GaAs were investigated. X-ray photoelectron spectroscopy (XPS) revealed the absence of arsenic oxides at the HfAlO/GaAs interface after dielectric growth and post-deposition annealing at 500 °C. A minimal increase in the amount of gallium oxides at the interface was detected between the as-deposited and annealed conditions highlighting the effectiveness of HfAlO in suppressing gallium oxide formation. An equivalent oxide thickness (EOT) of ∼ 2 nm has been achieved with a gate leakage current density of less than 10-4 A/cm2. These results testify a good dielectric interface with minimal interfacial oxides and open up potential for further investigation of HfAlO/GaAs gate stack properties to determine its viability for n-channel MOSFETs.

Nitrogen (N2) Implantation to Suppress Growth of Interfacial Oxide in Mocvd Bst and Sputtered Bst Films

1999 ◽  
Vol 567 ◽  
Author(s):  
Renee Nieh ◽  
Wen-Jie Qi ◽  
Yongjoo Jeon ◽  
Byoung Hun Lee ◽  
Aaron Lucas ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Interfacial Layer ◽  
Gate Dielectric ◽  
Nitrogen Concentration ◽  
Chemical Vapor ◽  
Future Generation ◽  
Oxide Thickness ◽  
Layer Growth ◽  
X Ray ◽  
Bst Films

ABSTRACTBa0.5Sr0.5TiO3 (BST) is one of the high-k candidates for replacing SiO2 as the gate dielectric in future generation devices. The biggest obstacle to scaling the equivalent oxide thickness (EOT) of BST is an interfacial layer, SixOy, which forms between BST and Si. Nitrogen (N2) implantation into the Si substrate has been proposed to reduce the growth of this interfacial layer. In this study, capacitors (Pt/BST/Si) were fabricated by depositing thin BST films (50Å) onto N2 implanted Si in order to evaluate the effects of implant dose and annealing conditions on EOT. It was found that N2 implantation reduced the EOT of RF magnetron sputtered and Metal Oxide Chemical Vapor Deposition (MOCVD) BST films by ∼20% and ∼33%, respectively. For sputtered BST, an implant dose of 1×1014cm−;2 provided sufficient nitrogen concentration without residual implant damage after annealing. X-ray photoelectron spectroscopy data confirmed that the reduction in EOT is due to a reduction in the interfacial layer growth. X-ray diffraction spectra revealed typical polycrystalline structure with (111) and (200) preferential orientations for both films. Leakage for these 50Å BST films is on the order of 10−8 to 10−5 A/cm2—lower than oxynitrides with comparable EOTs.

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