2011 ITRSEmerging Research Materials[ERM]April 10-13, 2011 Michael Garner – Intel Daniel Herr –SRC
MtM ITRS Workshop – April 13, 2011 • More-than-Moore Workshop at ITRS 2011 Spring Meeting • in Potsdam/Germany • (same location as ITRS spring meeting) • Target group: • ITRS community (A&P, Wireless, MEMS, …), everybodyinterested in & affected by MtM • + on invitation only: • individualsfromiNEMI, CATRENE SC Working Group, SRC, key experts fromacademia, institutes, SMEs, industry. • Forum to exchange information and viewsfromdifferent sources • to further guide, enhance, facilitateMtMroadmapping for 2011 ITRS roadmapwork (and beyond)
MtM ITRS Workshop – April 13, 2011 Tentative Agenda 08:30 – 08:50 ITRS White Paper & on-going actions M. Graef 08:50 – 10:20 Update ITRS ITWG activities on MtM wireless J. Pekarik (20mn) A&P B. Bottoms (20mn) MEMS (+iNEMI MtM roadmap) M. Gaitan (20mn) CATRENE WG summary M. Brillouët (30mn) 10:20 – 10:45 break 10:45 – 12:15 Parallel sessions: Power & Sensors for… Automotive (chair: R. Mahnkopf) Energy / Integ. power/ Lighting (chair: M. Graef) 12:15 – 13:15 lunch13:15 – 14:15 Sensors for… Healthcare Security and safety 14:15 – 14:55 4x10’ summary of the discussion rapporteurs 14:55 – 15:00 Wrap-up M. Brillouët tentative
MtM ITRS Workshop – April 13, 2011 Questions to be addressed for each domain what are the generic functions in this domain? which technologies / devices contribute to these generic functions? which generic functions (or underlying technologies) are suited for a roadmapping effort? (*) are there roadmap initiatives on these generic functions (or underlying technologies) in some regions? should ITRS roadmap these functions (or underlying technologies) or refer to these other initiatives? what would be the best frame / TWIGs to address these roadmaps in the ITRS context? (*) see criteria (FOM, LEP, WAT, SHR, ECO) in the MtM ITRS White Paper (http://www.itrs.net/Links/2010ITRS/IRC-ITRS-MtM-v2 3.pdf )
2010 Action Items • Top 10 difficult ERM challenges [16 nm, <16 nm] • The role of ESH in ITRS • 2011 Transitions • III-V & Ge to FEP & PIDS • 193nm EUV Extension Resist to Litho TWG? • Ultrathin Cu Barrier Materials • 3D Interconnect Emerging Materials Requirements • Prepare for 2011 Critical Assessments: • Alternate Channel Materials • Directed Self Assembly for Litho Extension • Novel Chip to Package Interconnects • Novel Cu Extension Materials
2010 ERM Participants Prashant Majhi Intel Witek Maszara Global Foundry Francois Martin LETI Fumihiro Matsukura Tohoku U. Nobuyuki Matsuzawa Sony Jennifer Mckenna Intel Claudia Mewes U. Alabama Yoshiyuki Miyamoto NEC Andrea Morello UNSW Boris Naydenov U. Stuttgart Paul Nealey U. Wisc. Kwok Ng SRC Fumiyuki Nihey NEC Yoshio Nishi Stanford U. Dmitri Nikonov Intel Yaw Obeng NIST Chris Ober Cornell Univ Katsumi Ohmori. TOK Yoshichika Otani Riken Inst. Jeff Peterson Intel Alexei Preobrajenski Lund Univ. Victor Pushparaj AMAT Ganapati Ramanath RPI Ramamoorthy Ramesh U.C. Berkeley Nachiket Raravikar Intel Heike Riel IBM Dave Roberts Nantero Mark Rodwell UCSB Sven Rogge Delft U. Jae Sung Roh Hynix Tadashi Sakai Toshiba Gurtej Sandhu Micron Krishna Saraswat Stanford U. Hideyki Sasaki Toshiba Nanoanalysis Shintaro Sato AIST Akihito Sawa AIST Barry Schechtman INSEC Thomas Schenkel LBNL Sadasivan Shankar Intel HiroAkinaga AIST Jesus de Alamo MIT Tsuneya Ando Tokyo Inst. Tech Dimitri Antoniadis MIT Nobuo Aoi Panasonic Koyu Asai Renesas Asen Asenov U. of Glasgow Yuji Awano Keio Univ David Awschalom UCSB. Kaustav Banerjee UCSB Daniel-Camille Bensahel ST Micro Stacey Bent Stanford U. Kris Bertness NIST Bill Bottoms Nanonexus George Bourianoff Intel Rod Bowman Seagate Alex Bratkovski HP Robert Bristol Intel Bernard Capraro Intel John Carruthers Port. State Univ. An Chen Global Foundry Eugene Chen Grandis Zhihong Chen IBM Toyohiro Chikyo NIMS Byung Jin Cho KAIST U-In Chung Samsung Luigi Colombo TI Hongjie Dai Stanford U. Thibaut Devolder Univ. Paris Sud Athanasios Dimoulas IMS Greece Catherine Dubourdieu L. Mat. Genie Phys. & IBM John Ekerdt U. of Texas Tetsuo Endoh Tohoku Univ. James Engstrom Cornell U. Michael Flatte U. Iowa Satoshi Fujimura TOK Michael Garner Intel Niti Goel Intel Michael Goldstein Intel Suresh Golwalkar Intel Wilfried Haensch IBM Dan Herr SRC Hiro Hibino NTT Bill Hinsberg IBM Judy Hoyt MIT Jim Hutchby SRC Ajey Jacob Intel David Jamieson U. Melbourne Ali Javey U.C. Berkeley James Jewett Intel Berry Jonker NRL Xavier Joyeux Intel Ted Kamins Consultant Zia Karim AIXTRON AG Takashi Kariya Ibiden Masashi Kawaski Tohoku U. Leo Kenny Intel Philip Kim Columbia U. Sean King Intel Atsuhiro Kinoshita Toshiba Michael Kozicki ASU Mark Kryder CMU Yi-Sha Ku ITRI Hiroshi Kumigashira U. Tokyo Y.J. Lee Nat. Nano Lab TW Liew Yun Fook A-Star Wei-Chung Lo ITRI Louis Lome IDA Cons. Gerry Lucovsky NCSU Mark Lundstrom Purdue U. Yale Ma Seagate Blanka Magyari-Kope Stanford U. Allan MacDonald Univ. of Texas Mizuki Sekiya AIST Matt Shaw Intel Takahiro Shinada Waseda Univ. Michelle Simmons UNSW Kaushal Singh AMAT Jon Slaughter Everspin Bruce Smith RIT Tsung-Tsan Su ITRI Maki Suemitsu Tohoku U. Naoyuki Sugiyama Toray C-Y Sung IBM Raja Swaminathan Intel Michiharu Tabe Shizuoka U. Hidenori Takagi U. of Tokyo Shin-ichi Takagi U. of Tokyo Koki Tamura TOK America Ian Thayne U. of Glasgow Yoshihiro Todokoro NAIST Yasuhide Tomioka AIST Mark Tuominen U. Mass Peter Trefonas Dow Ming-Jinn Tsai ITRI Wilman Tsai Intel Ken Uchida Tokyo Tech Yasuo Wada Toyo U Vijay Wakharkar Intel Kang Wang UCLA Rainer Waser Aacken Univ. Jeff Welser IBM/NRI C.P. Wong GA Tech. Univ. H.S. Philip Wong Stanford U. Dirk Wouters IMEC Wen-Li Wu NIST Hiroshi Yamaguchi NTT Toru Yamaguchi NTT Chin-Tien Yang ITRI Hiroaki Yoda Toshiba Jiro Yugami Renasas SC Zhang Stanford U. Yuegang Zhang LBNL Victor Zhirnov SRC Paul Zimmerman Intel
ERM for Emerging Research DevicesAlternate Channel Materials • Transition of n-III-V & p-Ge to PIDS & FEP • Nanowire Workshop Completed • CNT FET Materials WS Completed • P-InGaSb & n-Ge Update Needed • Graphene TBD • Memory Materials WS Completed
ERM Beyond CMOS • Update on Spin Materials • Update on Strongly Correlated Electron State Materials • Update on Molecular Materials • Interconnect Materials for Beyond CMOS Devices
Memory Materials • Memory Materials WS Completed • STT • Redox RAM
Alternate Channel Materials Key Messages • Nanowires • Grown NW need to demonstrate improved mobility over etched structures • Not demonstrated yet Large uncertainty in measurements) • Catalytic growth continues to be a problem (Au is most reproducible, but is incompatible with silicon) • Control of direction & orientation issues below 10nm diameter (Not adequately characterized) • Etched NW • Etched NW (square) have better mobility than etched and annealed NW (rounded) • Higher Dit • Surface roughness & Dit limit mobility in addition to confinement • Diameter control
Nanowire Metrology • Carrier Density, Mobility, and Dopant Concentration • Metrology needed for Qf and Dit on NW • Contact Resistance, Surface Passivation, and Reliability
n-Ge Key Messages • n-Ge channels show mobility enhancements when prepared with ozone-oxidized surfaces <400 cm2/V-s. • No results yet for full integration into Si MOSFET channels with high-k gate dielectrics • In addition S/D parasitic and contact resistances will need to be reduced to see these improvements
p-InGaSb Key Messages • p-InGaSb channels show mobility enhancements when prepared in strained heterostructure 800-1500 cm2/V-s • No results yet for full integration into Si MOSFET channels with high-k gate dielectrics • In addition S/D parasitic and contact resistances will need to be reduced to see these improvements
CNT Key Messages • Growth on quartz & Transfer • ~20 CNTs/µm
Graphene Key Messages • Need reasonable generation of a Bandgap • RF doesn’t need a bandgap • Width (2nm) • Vertical Electric Field • Anisotropic strain (Modeling) • Recent angle resolved photoemission 330mV Eg • Graphene on Ir surface “cluster” superlattice • Chemical surface functionalization • Mobility (BN growth looks promising) • Growth • CVD on quartz & SiO2 • Need continuous film • Defects need to be controlled
Memory Materials Key Messages (STT) • Shrinking STT is reducing switching energy consumption • Perpendicular MTJ required to continue scaling • Vertical magnetization requires new materials • High spin polarization • Low intrinsic damping • Tunable magnetic anisotropies
Memory Materials Key Messages (Redox) • Need to experimentally verify the physical state of filaments • Single filament vs. multiple sub-filaments • Need experiments to verify the switching mechanism • Role of vacancies • Role of thermal heating • Questions raised about Ti interstitials • Need to resolve • Single crystal mechanisms may be minor in polycrystalline or amorphous materials • Analysis needs to differentiate between the experimental results in these types of materials
Beyond CMOS • Spin Materials • FM Semiconductors • Semiconductor Materials for spin transport • MTJ materials • Ferromagnetic materials • Strongly Correlated Electron State Materials
Semiconductor Materials • FM Semiconductors • Need to update Tc for FM semiconductors • Need to review the status of nanomaterial Tc • Semiconductors for spin transport • Need to have a table of spin decoherence length • Need a table of spin orbit coupling in semiconductors
MTJ Materials • MgO thickness must be controlled • For continued scaling, need magnetization perpendicular to film plane • High magnetization • Low damping • High anisotropy • Modeling indicates • Low Damping: (CoFe)0.75Ge0.25
Oxide Definitions • Transition Metal Oxides • Oxides with only transition metals • Complex Metal Oxides • Metal oxides with a transition metal and non-transition metal • Metal oxides with electronic phase transitions • Multiferroics • Materials with two or more of the following coupled properties • Ferroelectric, ferromagnetic, ferroelastic, ferrotoroidal, antiferromagnetic
Strongly Correlated Electron State Materials • Mott Transition Materials (VO2) • Progress in electric control of phase transition • Electric Polarization Coupled to AFM coupled to FM metals • Improved coupling of electric field to magnetization • Magnetoelectric materials • LSMO, Superlattices • Need higher RT magnetization • Double Perovskites have higher magnetization, but not coupling of electric and magnetic properties • Novel SCEM Interface Phenomenon • 2D Electron gas etc. • “Dead Layer” thickness at interfaces
Mott Transition Materials • VO2: Undergoes an insulator-metal transition close to the structural phase transition • Can be electronically switched when close to the crystal phase transition • The field must be maintained to keep the material in the metallic state and the temperature must be maintained below the crystal phase transition • Oxygen stoichiometry must be controlled in thin films close to VO2.
Complex Metal Oxides • Filament Forming Process • Multiple models for forming process • Single Filament vs. Multiple parallel discontinuous sub filaments • Interstitials vs. oxygen vacancy filaments • Switching Process • Multiple Models for Switching • Interfacial • Vacancy, Vacancy Charge Trap, Interstitials
Litho Materials Key Messages • Transitioning evolutionary resist to Litho TWG • Directed Self Assembly • Progress on assembly of critical features • Recent progress on defect densities (<25cm-2) • Can defects approach ITRS requirement(<0.01cm-2) • Need defect metrology capable of characterizing defects in: • “Developed” DSA materials • Many issues are engineering vs. fundamental • Imprint polymers: Adhesion to substrate, but not the tool
FEP • Deterministic Doping • Periodicity of dopant placement is more important than exact uniformity of concentration • Cost effective options emerging • Self assembly of monolayers • BCP DSA combined with implant • Selective Etch and Deposition solutions needed
Interconnects • Sub 5nm Cu Barrier Layers • Progress in Monolayer barriers blocking Cu Diffusion • CNT Vias • Progress in increasing density of CNTs in vias • Achieving low contact resistance is major challenge • Graphene Interconnects • Progress in fabrication of graphene interconnects
“Hard” Metal/InOrganic Nanometer Scale Barriers: • Several different approaches in “development” phase and covered by Interconnects WG, including: • Self forming MnSiO4, • Direct plate barriers Ru • Some research at university level on direct plate barriers such as RuP, RuB, MnN. • Cu diffusion barrier testing still predominantly at > 5nm thickness. Recent report of MnN barrier at 2.5 nm. • Questions of whether traditional hard barrier deposition methods can produce continuous films at < 2 nm thickness – particularly with porous dielectrics and LER 2nm.
“Soft” Organic-Nanometer “Monolayer” Barriers: • Self Assembled Monolayers (SAMS): Lots of interesting results but still failing to completely impress. • SAM Barriers are better then no barrier but not equivalent to Ta/TaN or SiN:H for stopping Cu diffusion • Researchers like to say SAMS “impede” or “inhibit” Cu diffusion rather then address shortcomings relative to TNT • SAM Barriers typically tested with SiO2 ILD. Researchers really need to move to testing with porous low-k ILD. • Lots of questions of how SAMS will work in the presence of topography and/or defects (i.e. can they cover them?) • Some interesting results on SAMS as adhesion promoters. This could be a possible entry path into mainstream. • Organic Barriers: Results no looking promising • MLD Organic Cu Barriers have clearly shown Cu in diffusion up to 6nm. • It is not clear that there is a credible roadmap to make this approach work. • MLD Organic films may have more use as pore sealants for porous low-k dielectrics.
Cu Barrier Needs: • More characterization of barrier performance and continuity of “hard” films at < 2 nm thickness on porous ILDs with 2nm surface roughness. • Head to head comparison of “hard” and “soft” barriers both at < 2-3nm thickness. • Research on combination bilayer “hard” and “soft” nm barrier films. Specifically can the two be utilized in combination to address the short comings of each at < 2nm thickness.
Assembly & PackageKey Messages • 3D ERM Focus • Materials with a thermal hierarchy for assembly • Chip attach materials: Nanosolders have potential for thermal hierarchy • Need flux to eliminate surface oxide on nanoparticles • Electrically insulating materials with high thermal conductivity • Designing Polymer Properties • Additions of small amounts of nanomaterials can change properties • Modulus, thermal conductivity, and other mechanical properties • BUT, CTE appears to depend on volume % of material
Assembly & Package • CNTs for Chip Attach • Progress on increasing the density • Method to transfer CNT bundles • Achieving low contact resistance remains the major issue • Chip Attach materials with thermal hierarchy • Nanometals melt at lower temperatures due to surface energy • Initial melting may be surface fusion that doesn’t form complete melting • Surface oxide layers could inhibit the surface melting • May require development of new fluxes to break down oxides
Assembly & Package • Thermal Interface Materials • CNTs in polymers can increase thermal conductivity • CNT thermal contact resistance continues to be a problem • CNTs also decrease the electrical resistivity: would limit use in 3D interconnects
ITRS Memory Materials– November 30, 2010Agenda 8:30 Gathering 9:00 Welcome and Introductions Garner 9:10 Review Redox Challenges (Barza) Hutchby, Lucosky, and Magyari-Kope 9:40 Atomic switches Aono (NIMS) 10:10 Characterization of Mechanisms Kozicki 10:40 Break 10:50 Macroscopic Vacancy Mechanism Hwang (GIST) 11:20 Scaling Issues related to the mechanism Zhirnov 11:50 <<Panel Discussion of Redox and metal filament mechanisms>> Panelist : 10 min / each + discussion Direct observation of Redox reactions in resistance random access memory Kumigashira (Tokyo) Oxide Vacancy Physical Mechanisms Lucovsky Modeling Oxygen Vacancies in Redox Devices Magyari-Kope Characterization of Mechanisms Kozicki Device Operation Zhirnov 13:00 Lunch * Q&A time with longer-than 5 min is strongly required for each speaker.
ITRS Memory Materials– November 30, 2010 Agenda 14:00 STT Requirements Chung 14:15 STT RAM Introduction Chen 14:45 STT RAM Energy Challenges Slaughter 15:15 Energy of the Write Mechanism Devolder 15:45 Break 16:00 Scalable STT RAM Technology for Low Power Systems Endoh 16:30 Modeling Mewes 17:00 Low-power & ultra-fast MRAM(tentative) Ishiwata 17:30 Process Integration Effect on Tunnel Barrier & Magnetic Interfaces Lee 18:00 Role of Interfaces Kryder << Summary session for Redox RAM and STT-RAM>> 18:30 Summary of Research Needs & Discussion Hiro, Eugene 19:00 Close * Q&A time with longer-than 5 min is strongly required for each speaker.
Redox Memory Scope and Objectives • The Redox Memory materials to be evaluated in this meeting are binary metal oxides, such as TiO2, HfO2, and Ta2O5. The electrodes will include Cu and Ag which form conductive filaments and also “non-migrating” electrodes, such as Pt etc., compatible with formation of redox filaments. • How can we experimentally verify that a specific Redox RAM operating mechanism is working in the memory device with the realistic cell size? • Does it require a combination of simulation and experimentation? • What is the limit of scaling and limiting factor? • What is the factor of the reliability?
Panel discussion of Redox Memory Questions to the panelist • How can we experimentally verify that the Redox RAM operating mechanism? • What is the limit of scaling and limiting factor? • What is the limiting factor of the reliability? • Other difficult challenges in the ReRAM technology
STT RAM Scope and Objectives • What materials or interface research should be performed to enable reduction of Write Energy by 10X? • STT RAM requires magnetic materials with fields aligned perpendicular to the substrates • Materials issues that could limit scalability • Identify the research needed on the materials and interfaces to validate the scalability of these mechanisms. • Modeling to assess tradeoffs in reduction of write energy vs. retention time and on/off resistance is needed.
Memory Materials Workshop 2010.11.30, Tsukuba, Japan (38 participants) Redox RAM: How can we experimentally verify that the Redox RAM operating mechanism? STT-RAM: What materials or interface research should be performed to enable reduction of write energy by 10X? Even with the combination of MgO-CoFeB (normally in-plane), interface control enables Perpendicular MTJ.
Redox RAM • Status: Models exist for two different redox material devices • Metal filament for cation diffusive electrodes • Cu, Ag • Vacancy filament for oxygen vacancy based devices (TiO2) • Pt or Ti electrodes • “Vacancy” filaments • Other mechanisms may exist dominate in other oxides • Need experiments to verify that the Redox operating mechanism models are correct.
Experiments to Verify Redox Operating Mechanism Models • Explore time and voltage dependent switching • Determine the switching threshold voltage threshold • Nanoscale characterization of filament operation • PEEM to characterize oxidation states in filaments • Characterize oxidation states of Redox devices in On/Off States
STT RAM • STT RAM with polarization in plane is more mature • STT-RAM with perpendicular polarization is in competitive development • Lack of consensus on magnetic materials is limiting progress • Need magnetic materials with increased perpendicular magnetization and lower damping • Significant improvement in interface roughness and edge damage to reduce damping • Reduce defects in MgO tunnel barriers and improve thickness uniformity (0.9 to 1.2nm thickness) • Many of these are technology development issues vs. emerging research materials issues
STT RAM ERM/ERD Recommendations • PIDS & FEP or Interconnects Add Perpendicular STT Requirements to Their Chapters • ERM focus on materials to interface STJ & STT Elements to Beyond CMOS Spin Devices
Transition of III-V & Ge to PIDS & FEP • VLSI Tech Symposium WS June, 2010 • Maturity Survey: Completed September, 2010 • PIDS and FEP Proposing to Develop Detailed Requirements for III-V and Ge in 2011 • Workshop at IEDM SF, December, 2010
Potential Changes to ERM (2011) • Transition of n-III-V & p-Ge to PIDS & FEP • Identify ERM III-V support needed by PIDS • Contacts, Dopant activation • STT Support needed by FEP-PIDS • Critical Assessment of Alternate Channel Materials • p-III-V • Nanowires • CNTs • Graphene • Graphene Bandgap (Strain??) • Update MultiFerroic Device Materials • ESH Interaction
III-V & Ge Transition Assessment Process • VLSI Technology III-V Workshop • August Teleconference Workshop • Survey Table (Metrics, targets, and status) before September 1 • Survey Sent to Participants: Sept. 1, 2010 • Surveys September 17, 2010 • IEDM III-V Workshop