Electronic Materials Group-People

Graduate Students

Ekaterina Zoubenko

Ekaterina Zoubenko


PhD student

B.Sc. Physics, Technion (2015)  B.Sc. Materials Science and Engineering, Technion (2015)

Room: 507, Meidan Building 5th floor

Tel: +972-4-8295798

katiaz@campus.technion.ac.il

Ekaterina received a double degree in Physics and Materials Science and Engineering at the Technion in 2015. Ekaterina has joined Electronic materials group under the supervision of Prof. Moshe Eizenberg in 2015 and passed to a PhD-direct track in 2017. The objective of her research is to study the modification of the effective work function (EWF) of refractory metals-based metallization deposited by atomic layer deposition (ALD) for advanced metal-oxide-semiconductor (MOS) structures.

ALD of metallic materials, such as metal nitrides, carbides, and binary alloys, is of particular scientific and technological interest for high-k metal-gate (HKMG) devices, since it is a flexible tool for tuning the electrical performances through compositional and structural variation of the deposited gate-metal. The metal/dielectric EWF is one of the important parameters that determine the device performance and its tuning is a significant challenge in the HKMG technology.

A thorough characterization of ALD deposited ultrathin metallic films and a correlation with MOS electrical properties are necessary to study the modification of the metal/dielectric EWF.


Former Graduate Students

Sivan Fadida

Sivan

B.A. Chemistry, B.Sc Materials Science & Engineering (2010 Technion)

Tel: +972-4-8295798

Fax: +972-4-8295677

sivanfa@campus.technion.ac.il

 

I am a PhD student in the electronic materials group. Prof. Moshe Eizenberg is my supervisor.

My research deals with tuning the electrical properties of high-K dielectric gate stacks on Ge substrate with a metal gate electrode. Ge has become of great interest as a channel material for future p- type transistors due to its high hole mobility. Unfortunately, Ge is also known for its poor quality of interface, and for its unstable oxides. A great challenge is to find a stack of oxides that would passivate interface states and on the other hand would perform as a high K gate oxide for future devises. This requires a stake of high-K dielectrics.

A few metal oxides with promising dielectric properties will be studied as the stack layers. As a part of the research, the compatibility of these oxides to the Ge system will be examined: stability of the interface, valence and conduction band offsets, chemical bonding and so on.

The role of the metal gate electrode is also an important aspect of my research.

A thorough characterization of the stack is necessary in order to better understand the effect of the layers thickness, structure, composition and location in the stack on the electrical properties of the gate stack.

Publications:

S. Fadida, M. Eizenberg, L. Nyns, S. Van Elshocht, and M. Caymax, “Band Alignment of Hf-Zr Oxides on Al2O3\GeO2\Ge Stacks”, Microelectron. Eng. 88, (2011), 1557-1559.


Pini Shekhter

Pini Shekhter

B.Sc. Chemistry, Technion (2011)

B.Sc. Materials Science & Engineering, Technion (2011)

Tel: +972-4-829-5798

Fax: +972-4-829-5677

pini@campus.technion.ac.il

I am a PhD student at the Electronic Materials Group in the Department of Materials Engineering under the supervision of Prof. Moshe Eizenberg.

My research is focused on the investigation of epitaxially grown rare-earth oxides and the affects of strain on their electric and dielectric properties.

Most of the research of high-k dielectrics for different applications, nowadays, is centered on amorphous oxides. Another approach is using single crystalline oxides. The oxides that match the crystal of Si and Ge (in (111) orientation) are oxides of rare-earth materials such as Gd, Nd or Pr.

The study of the interfaces these oxides have with semiconductors in terms of lattice mismatches and defects and the way they change the function of these oxides is done through using a combination of methods, including:  electrical measurements, electron and x-ray spectroscopy and electron microscopy.

Publications:

  • P. Shekhter, D. Schwendt, Y. Amouyal, T. F. Wietler, H. J. Osten and M. Eizenberg, “Strain-induced phase variation and dielectric constant enhancement of epitaxial Gd2O3”, J. Appl. Phys. 120, 014101 (2016).
  • R. Winter, P. Shekhter, K. Tang, L. Floreano, A. Verdini, P. C. McIntyre, and M. Eizenberg, “Effects of titanium layer oxygen scavenging on the high-k/InGaAs interface”, ACS Appl. Mater. Interfaces 8, 16979 (2016).
  • P. Shekhter, C. Uzan-Saguy, J. Schubert, Y. Amouyal, and M. Eizenberg, “Experimental and computational study of zero dimensional metallic behavior at the LaLuO3/SrTiO3 interface”, J. Vac. Sci. Technol. B 34, 021204 (2016).
  • F. Palumbo, P. Shekhter, K. C. Weinfeld and M. Eizenberg, “Characteristics of the dynamics of breakdown filaments in Al2O3/InGaAs stacks” Appl. Phys. Lett. 107, 122901 (2015).
  • P. Shekhter, A. R. Chaudhuri, A. Laha, S. Yehezkel, A. Shriki, H. J. Osten, and M. Eizenberg, “The influence of carbon doping on the performance of Gd2O3 as high-k gate dielectric”, Appl. Phys. Lett. 105, 262901 (2014).
  • S. Fadida, P. Shekhter, D. Cvetko, L. Floreano, A. Verdini, L. Nyns, S. Van Elshocht, I. Kymissis and M. Eizenberg, “Direct observation of both contact and remote oxygen scavenging of GeO2 in a metal-oxide-semiconductor stack”, J. Appl. Phys. 116, 164101 (2014).
  • P. Shekhter, F. Palumbo, K. Cohen Weinfeld and M. Eizenberg, “X ray photoelectron analysis of oxide-semiconductor interface after breakdown in Al2O3/InGaAs stacks”, Appl. Phys. Lett. 105, 102908 (2014).
  • H. J. Osten, D. Schwendt, A. Chaudhuri, A. Fissel, P. Shekhter and M. Eizenberg, “Tuning Dielectric Properties of Epitaxial Lanthanide Oxides on Silicon”, ECS Transactions 61, 3 (2014).
  • F. Palumbo, P. Shekhter and M. Eizenberg, “Influence of the oxide–semiconductor interface on the resistive switching phenomenon in metal/Al2O3/InGaAs”, Solid-State Electronics 93, 56 (2014).
  • P. Shekhter, S. Mehari, D. Ritter and M. Eizenberg, “Epitaxial NiInGaAs Formed by Solid State Reaction on In0.53Ga0.47As: Structural and Chemical Study”, J. Vac. Sci. Technol. B 31, 031205 (2013).
  • F. Palumbo, P. Shekhter, I. Krylov, D. Ritter, M. Eizenberg, “Resistive switching effect on Al2O3/InGaAs stacks”, Microelectronic Engineering 109, 83 (2013).
  • L. Kornblum, P. Shekhter, Y. Slovatizky, Y. Amouyal and Moshe Eizenberg,“Composition and Crystallography Dependence of the Work Function: Experiment and Calculations of Pt-Al Alloys”, Phys. Rev. B, 86, 125305 (2012).
  • S. Mehari, A. Gavrilov, S. Cohen, P. Shekhter, M. Eizenberg and D. Ritter, “Measurement of the Schottky barrier height between Ni-InGaAs alloy and In0.53Ga0.47As”Appl. Phys. Lett.101, 072103 (2012).
  • D. Schwendt, H. J. Osten, P. Shekhter, and M. Eizenberg, “Strain-induced effects on the dielectric constant for thin, crystalline rare earth oxides on silicon”Appl. Phys. Lett.100, 232905 (2012).
  • P. Shekhter, L. Kornblum, Z. Liu, S. Cui, T. P. Ma and M. Eizenberg, “Effect of Hydrogen on the Chemical Bonding and Band Structure at the Al2O3/In0.53Ga0.47As Interface“, Appl. Phys. Lett.99, 232103 (2011).
  • Z. Liu, S. Cui, P. Shekhter, X. Sun, L. Kornblum, J. Yang, M. Eizenberg, K. S. Chang-Liao and T. P. Ma, “Effect of H on interface properties of Al2O3/ In0.53Ga0.47As”Appl. Phys. Lett.99, 222104 (2011)

Igor Krylov

Igor

Β.Sc. Materials Science & Engineering, (summa cum laude), Technion (2010)

B.Sc. Chemistry, (summa cum laude), Technion(2010)

Tel. +972-4-8295798

Fax. +972-4-8295677

krylov@campus.technion.ac.il

Ph.D. student at the Nanoscience and Nanotechnology Program of Russel Berrie Nanotechnology Institute (RBNI).

An effective passivation layers is a key for the wide implementation of III-V compound semiconductors based devices into integrated circuits. The aim of the passivation layers is significantly decrease of interface states density which always presents in the surface of any semiconductor. Interface states are responsible for Fermi level pinning, recombination current, surface mobility degradation, threshold voltage instability and the wide spectrum of other undesirable effects for good devices performance.  My research takes place under common supervision of prof. Ritter (Electrical Engineering) and prof. Eizenberg (Materials Engineering) and focuses on development of nitride based passivation layers for InGaAs related devices using Atomic Layer Deposition (ALD) and Plasma Enhanced Chemical Vapor Deposition (PECVD).

Teaching:

Winter:

044231 – Electronic Devices 1

127427 – Solid State

Spring:

315003 – Thermodynamics of Materials

044125 – Principles of Semiconductor Devices

Publications:

  • High – K materials 9  , “Si3N4 as a Useful Dielectric for InGaAs MIS Stacks” I. Krylov, A.Gavrilov, S.Cohen, D.Ritter, and M. Eizenberg
  • “Elimination of the weak inversion hump in Si3N4/InGaAs (001) gate stacks using an in situ NH3pre-treatment “,I. Krylov, A. Gavrilov, D. Ritter, and M. Eizenberg, Appl. Phys. Lett. 99, 203504 (2011)
  • “Experimental evidence for the correlation between the weak inversion hump and near midgap states in dielectric/InGaAs interfaces “,I. Krylov, L. Kornblum, A. Gavrilov, D. Ritter, and M. Eizenberg, Appl. Phys. Lett.100, 173508 (2012)
  •  “Correlation between Ga-O signature and midgap states at the Al2O3/In0.53Ga0.47As interface “, I. Krylov, A. Gavrilov, M. Eizenberg, and D. Ritter,  Appl. Phys. Lett. 101, 063504 (2012).

Roy Winter

roy_winterB.Sc. Physics, Technion (2012)

B.Sc. Materials Science & Engineering, Technion (2012)

Tel: +972-4-8295798

Fax: +972-4-8295677

Winroy86@gmail.com

I am a Ph.D. student at the electronic materials group in the department of materials science and engineering under the supervision of Prof. Moshe Eizenberg.

The dramatic improvements in the microelectronics industry are the result of aggressive scaling of devices, particularly in physical dimensions. The thermally grown silicon-dioxide (SiO2) gate insulators have been recently replaced with high-k dielectric materials in order to reduce the gate leakage current. Additionally, the highly doped poly-Si gate electrode has been replaced with a metal electrode. Metal electrodes have lower resistance and solve the problems of gate depletion and boron penetration. In parallel, there has been in recent years an increasing emphasis on new channel materials. For high mobility n-MOS devices, research in recent years has focused on InGaAs channels.

The main difficulty today in achieving satisfying performance for metal/oxide/semiconductor field effect transistor (MOSFET) devices based on InGaAs is in controlling the Fermi level pinning (FLP) due to traps at the sub-nanometric dielectric/semiconductor and metal/dielectric interfaces. The great importance of this research will be in correlating FLP with the materials constituting the gate stack and processing steps. The most interesting parameter to study, in my view, is the role of interfaces and defects in controlling the properties of InGaAs MOS devices.

Publications:

  • R. Winter, J. Ahn, P. C. McIntyre, and M. Eizenberg, “New method for determining flat-band voltage in high mobility semiconductors”, J. Vac. Sci. Technol. B 31, 030604 (2013).
  • R. Winter, I. Krylov, J. Ahn, P. C. McIntyre, D. Ritter, and M. Eizenberg, “The effect of post oxide deposition annealing on the effective work function in metal/Al2O3/InGaAs gate stack”, Appl. Phys. Lett. 104, 202103 (2014).
  • F. Palumbo, R. Winter, I. Krylov, and M. Eizenberg, “Characteristics of stress-induced defects under positive bias in high-k/InGaAs stacks”, Appl. Phys. Lett. 104 (25), 252907 (2014).
  • I. Krylov, R. Winter, D. Ritter, and M Eizenberg, “Indium out-diffusion in Al2O3/InGaAs stacks during anneal at different ambient conditions”, Appl. Phys. Lett. 104 (24), 243504 (2014).
  • R. Winter, I. Krylov, C. Cytermann, K. Tang, J. Ahn, P. C. McIntyre, and M. Eizenberg, “Fermi level pinning in metal/Al2O3/InGaAs gate stack after post metallization annealing”, Journal of Applied Physics 118 (5), 055302 (2015).
  • K. Tang, R. Winter, L. Zhang, R. Droopad, M. Eizenberg, and P.C. McIntyre, “Border trap reduction in Al2O3/InGaAs gate stacks”, Appl. Phys. Lett. 107, 202102 (2015).
  • R. Winter, P. Shekhter, K. Tang, L. Floreano, A. Verdini, P.C. McIntyre and M. Eizenberg, “Effects of Titanium Layer Oxygen Scavenging on the High-k/InGaAs Interface”, American Chemical Society., 8 (26), 16979 (2016).
  • F. Palumbo, S. Pazos, F. Aguirre, R. Winter, I. Krylov, and M. Eizenberg, “Temperature dependence of trapping effects in metal gates/Al2O3/ InGaAs stacks”, Solid-State Electronics, under review (2016).
  • R. Winter, M. Kwan, P. H. Mutin, G. Ramanath, M. Eizenberg, “Chemical bonding and nanomolecular length effects on work function at Au- organophosphonate-HfO2 interfaces”, American Chemical Society., under review (2016).