Istituto per la Microelettronica e Microsistemi IMM The

Istituto per la Microelettronica e Microsistemi IMM The network on graphene at IMM OUTLINE • The IMM graphene research network • The agreement with Industry • Competences and acquired know how at IMM Agrate (MDM) • Competences and acquired know how at IMM CT Atom_based Nanotechnology workshop, 19 th January 2011, Arcetri (FI), Italy Slide 1/15

The graphene research network at IMM Graphene like materials (silicene, germanene, …) Memories and logics Milano Advanced characterisation & sensors See V. Morandi, R. Rizzoli Bologna Roma Lecce Napoli Catania materials fundamentals & devices (Rf, power, …) Atom_based Nanotechnology workshop, 19 th January 2011, Arcetri (FI), Italy Slide 2/15

The graphene research network at IMM Graphene like materials (silicene, germanene, …) Memories and logics Milano Advanced characterisation & sensors See V. Morandi, R. Rizzoli Bologna Roma Lecce Napoli Catania materials fundamentals & devices (Rf, power, …) Atom_based Nanotechnology workshop, 19 th January 2011, Arcetri (FI), Italy Slide 3/15

The graphene research network at IMM Graphene like materials (silicene, germanene, …) Memories and logics Milano Advanced characterisation & sensors See V. Morandi, R. Rizzoli Bologna Roma Lecce Napoli Catania materials fundamentals & devices (Rf, power, …) Atom_based Nanotechnology workshop, 19 th January 2011, Arcetri (FI), Italy Slide 2/15

The graphene research network at IMM Graphene like materials (silicene, germanene, …) Memories and logics Milano Bologna Roma Lecce Advanced characterisation & sensors See V. Morandi, R. Rizzoli The industrial cluster Napoli Catania 3 Sun materials fundamentals & devices (Rf, power, …) Atom_based Nanotechnology workshop, 19 th January 2011, Arcetri (FI), Italy Slide 2/15

The graphene research network at IMM Graphene like materials (silicene, germanene, …) Memories and logics Milano Bologna Roma Lecce Advanced characterisation & sensors See V. Morandi, R. Rizzoli The industrial cluster Napoli Catania 3 Sun. J. D. A. materials fundamentals & devices (Rf, power, …) Atom_based Nanotechnology workshop, 19 th January 2011, Arcetri (FI), Italy J. D. A. J. D. P. Slide 2/15

IMM-Agrate expertise on Re. RAM memory devices IMM CNR- Challenge: Resistive Random Access Memory IMM- Agrate EMMA Project-FP 6 (1/9/2006 -30/11/2009): Emerging single layer graphene as electrode on Nb-doped STO (Re. RAM) in graphene. Materials for Mass-storage Architectures (contact: Marco Fanciulli and Sabina Spiga) MORE Project 2010 -2012 (CARIPLO): Advanced Metal. Oxide heterostructure for nanoscle Re. RAM (contact: Sabina Spiga) substrate for Pt/Ni. O/graphene nano-Re. RAM graphene J. Y. Son et al. , ACS Nano 4, 2010, 2655 -2658 Re. RAM: a large class of emerging non-volatile memory concepts is based on a 2 -terminal resistor as a memory element that can be programmed in a high and low conductive state Memristor concept introduced by HP Graphene Oxide Thin Films (as switching element) for Flexible Nonvolatile Memory applications H. Y. Jeong at al. , Nanoletters 2010, 4381– 4386 Large interest from worldwide industries on Re. RAM for post high-density FLASH and for Flexible Nonvolatile Memory Applications IMM-Agrate expertise up to now: Ni. O, Nb 2 O 5, Ti. O 2 based metal/oxide/metal thin film- and nanowireheterostructures Atom_based Nanotechnology workshop, 19 th January 2011, Arcetri (FI), Italy Slide 3/15

Challenge: Graphene-like materials IMM CNR- IMM- Agrate Graphene like semiconductors (silicene, germanene) valuable option for active material in Post-CMOS ditital logic devices and circuits Option 2: encapsulation silicene with 2 D hexagonal dielectric lattices Option 1: silicene on metals, (in analogy with graphene) MBE of Si on Ag(110), Ag(111) substrates Ref. Aufray et al, Appl. Phys. Lett. 97, 223109 (2010); Aufray et al, ibidem 96, 183102 (2010) graphite-like Al. N 2 D top lattice functionalized silicene graphite-like Al. N 2 D bottom lattice • Molecular beam epitaxy apparatus for growth, functionalization amd in situ characterization of graphene like materials • in situ SPM and spectroscopic diagnostic tools @ CNR-IMM (Lab. MDM) • dielectric capping for prototypical MOS-like devices Atom_based Nanotechnology workshop, 19 th January 2011, Arcetri (FI), Italy Slide 4/15

GRAPHENE at IMM-CT: highlights IMM More than 30 papers since 2005 by two groups (theory & Exp. ) growth methods Synthesis methods ØMechanical exfoliation of highly oriented pyrolityc graphite (HOPG) ØChemical exfoliation of highly oriented pyrolityc graphite (HOPG) ØEpitaxial graphene on Si. C by controlled graphitisation of the surface at high temperatures (1500 – 2000 °C) in inert gas ambient High material quality: Low defects density, High mobility Can be placed on different substrates: Si. O 2 , Si. C, high-k dielectrics High production yield Can be placed on different substrates: Si. O 2 , Si. C, high-k dielectrics Large area (wafer scale) sheets on semiconductor substrate Small sheets; Low production yield Small sheets; Defects Substrate cost S. Sonde, F. Giannazzo, V. Raineri, and E. Rimini, J. Vac. Sci. Technol. B 27, 868 (2009). S. Sonde, F. Giannazzo, V. Raineri, and E. Rimini, Phys. Status Solidi B, 1– 4 (2010) S. Sonde, F. Giannazzo, V. Raineri, R. Yakimova, J. -R. Huntzinger, A. Tiberj, and J. Camassel, Phys. Rev. B 80, 241406(R) (2009). Atom_based Nanotechnology workshop, 19 th January 2011, Arcetri (FI), Italy Slide 5/15

GRAPHENE at IMM-CT: highlights IMM More than 30 papers since 2005 by two groups (theory & Exp. ) growth methods Synthesis methods ØMechanical exfoliation of highly oriented pyrolityc graphite (HOPG) High material quality: Low defects density, High mobility Can be placed on different substrates: Si. O 2 , Si. C, high-k dielectrics Small sheets; Low production yield ØChemical exfoliation of highly oriented pyrolityc graphite (HOPG) High production yield Can be placed on different substrates: Si. O 2 , Si. C, high-k dielectrics ØEpitaxial graphene on Si. C by controlled graphitisation of the surface at high temperatures (1500 – 2000 °C) in inert gas ambient BEYOND STATE OF THE ART Large area (wafer scale) sheets on semiconductor substrate Small sheets; Defects Substrate cost First EG on 4 H-Si. C off axis Patended substrates S. Sonde, F. Giannazzo, V. Raineri, and E. Rimini, J. Vac. Sci. Technol. B 27, 868 (2009). S. Sonde, F. Giannazzo, V. Raineri, and E. Rimini, Phys. Status Solidi B, 1– 4 (2010) S. Sonde, F. Giannazzo, V. Raineri, R. Yakimova, J. -R. Huntzinger, A. Tiberj, and J. Camassel, Phys. Rev. B 80, 241406(R) (2009). High mobility Atom_based Nanotechnology workshop, 19 th January 2011, Arcetri (FI), Italy Slide 5/15

GRAPHENE by. IMM-CT: Highlights Transfer at of Si. O Phosphonization of Si. O Silanization 2 2 IMM Transfer to substrates: methods and nanoimprinting functionalization Atom_based Nanotechnology workshop, 19 th January 2011, Arcetri (FI), Italy Slide 6/15

GRAPHENE by. IMM-CT: Highlights Transfer at of Si. O Phosphonization of Si. O Silanization 2 2 IMM Transfer to substrates: methods and nanoimprinting functionalization CHALLENGES • From nanoscale properties to large area EG on 4 H-Si. C (150 mm) • Functionalisation (to control the G carrier concentration, to control the G layer transfer to other substrates) Atom_based Nanotechnology workshop, 19 th January 2011, Arcetri (FI), Italy Slide 6/15

GRAPHENE at IMM-CT: Highlights Quantum capacitance and local transport IMM SCM Electronic Module Graphene n-Si. C Qscr Aeff Qdepl n+ Si. C Under the influence of electric field, 2 DEG+ Vg manifests itself as a Gnd capacitor, Quantum capacitor. C’q C’depl Aeff ΔVgr ΔVdepl Si. O leff Si. C + Vg F. Giannazzo, S. Sonde, V. Raineri, E. Rimini, Nano Lett. 9, 23 (2009). F. Giannazzo, S. Sonde, V. Raineri, and E. Rimini, Appl. Phys. Lett. 95, 263109 (2009). Atom_based Nanotechnology workshop, 19 th January 2011, Arcetri (FI), Italy Slide 7/15

IMM GRAPHENE at IMM-CT: Highlights The role of interfaces on mobility 23000 cm 2 V-1 s-1 Epitaxial graphene Nci_EG=2. 5 x 1011 cm-2 Giannazzo F, Roccaforte F, Raineri V, Liotta SF, Europhys. Lett. , 74, 686 (2006) S. Sonde, F. Giannazzo, C. Vecchio, V. Raineri, E. Rimini, App. Phys. Lett. , 97, 132101 (2010) Also selected for publication on Virtual Journal of Nanoscale Science & Technology. Atom_based Nanotechnology workshop, 19 th January 2011, Arcetri (FI), Italy Slide 8/15

GRAPHENE at IMM-CT: Highlights IMM From thin to fat FET Atomic force microscopy Optical microscopy HSQ EG Source Pt Gate Pt Lg=10 mm Drain Pt 4 H-Si. C (0001) n+ F. Giannazzo, C. Vecchio, V. Raineri, E. Rimini, submitted Atom_based Nanotechnology workshop, 19 th January 2011, Arcetri (FI), Italy Slide 9/15

GRAPHENE at IMM-CT: Highlights IMM fat FET characteristics Output characteristics 0 V < VD< 10 V 0 V < VG< 14 V STEP = 1 V Ambipolar transport Transconductance Electron Transfer characteristics conduction Hole conduction Dirac point Atom_based Nanotechnology workshop, 19 th January 2011, Arcetri (FI), Italy Slide 10/15

GRAPHENE at IMM-CT: challenges IMM 100 first processing end of processing 80 Mapping distribution Frequency (%) 60 40 20 0 0 100 80 20 40 60 l (nm) 80 100 60 40 20 0 0 2000 4000 6000 8000 m (cm 2 V-1 s-1) Atom_based Nanotechnology workshop, 19 th January 2011, Arcetri (FI), Italy Slide 11/15

GRAPHENE at IMM-CT: challenges IMM 100 first processing end of processing 80 Mapping distribution Frequency (%) 60 40 20 0 0 100 80 20 40 60 l (nm) 80 100 60 40 20 New devices architectures 0 0 2000 4000 6000 8000 m (cm 2 V-1 s-1) Buried gate CHALLENGES • Physical model nano- macro properties • New devices architectures Atom_based Nanotechnology workshop, 19 th January 2011, Arcetri (FI), Italy Slide 11/15

GRAPHENE at IMM-CT: ELECTRON STRUCTURE AND COHERENT TRANSPORT IN CONFINED GRAPHENE IMM Methodology Electronic Structure Quantum transport Ab initio Semiempirical Transport Density functional theory, LDA and GGA exchangecorrelation functionals, GAUSSIAN and SIESTA codes Tight-Binding (TB): single π-orbital Hamiltonian, further parameterizations based on DFT Non-equilibrium Green’s functions methods coupled to Landauer-Büttiker approach Extended Hückel Theory (EHT): real-orbital basis, parameters from DFT calculations or experimental data Atom_based Nanotechnology workshop, 19 th January 2011, Arcetri (FI), Italy Electrostatics 3 D Poisson solver, computational box with Neumann/Dirichlet boundary conditions Slide 12/15

GRAPHENE at IMM: Highlights IMM the simulation approach to transport properties Previous activity overview Computation apparatus: self-consistent transport calculations Atomistic modeling of disorder in graphene based systems: from the single defect/impurity to a finite density of scattering centers GNR-metal junction At CNR-IMM Catania Epitaxial GNR on Si. C(0001): role of interface states • In house programming codes for Focus on defective and functionalized epitaxial GNR electronic structure and quantum Complete device simulation transport based on atomistic semiempirical Hamiltonians (Extended Hückel and Tight-Binding), NEGFPoisson scheme • Full-device simulation for 103 – 107 atoms (in the case of GNRs) • Atomistic treatment of local alterations in the atomic structure, disorder, etc. • Multiscale approach (electronic Hamiltonians calibrated or evaluated by first-principles calculations) A. La Magna et al, PRB 80, 195413 (2009) I. Deretzis and A. La Magna, Appl. Phys. Lett. 95, 063211 (2009) I. Deretzis et al. , J. Phys. Cond. Mat. 22, 095504 (2010) I. Dertzis et al. , Phys. Rev. B 81, 085427 (2010) I. Deretzis et al. , Phys. Rev. B 82, 161413(R) (2010) I. D. and A. La Magna, accepted Appl. Phys. Lett. Atom_based Nanotechnology workshop, 19 th January 2011, Arcetri (FI), Italy Slide 13/15

Challenges IMM - Agrate • Memories and logics in graphene • Graphene-like materials IMM - CT • From nanoscale properties to large area (150 mm wafers) • Physical model considering nano-properties for macro-effects • New devices architectures • Functionalisation (to control the G carrier concentration, to control the G layer transfer to other substrates) • Computational transport properties: multi scale approach IMM - Bo • see coming presentations for details Atom_based Nanotechnology workshop, 19 th January 2011, Arcetri (FI), Italy Slide 14/15

Catania: IMM Bologna: Antonino La Magna* Vittorio Morandi* Giuseppe Angilella** Luca Ortolani*** Ioannis Deretzis*** Rita Rizzoli* Giulio Paolo Veronese* Raffaella Lo Nigro* Alberto Roncaglia* Filippo Giannazzo* Vito Raineri* Emanuele Rimini** Sushant Sonde*** Thank you for your attention Carmelo Vecchio **** Agrate: Marco Fanciulli** Alessandro Molle* Sabina Spiga* Atom_based Nanotechnology workshop, 19 th January 2011, Arcetri (FI), Italy * Ricercatori CNR di ruolo ** Associati *** Post-doc **** Dottorandi Slide 15/15