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Publié le 23 mars 2019
Present position
Executive Director of SPINTEC, UMR CEA-CNRS-UGA-G-INP

Lucian has been conducting research on nanomagnetism and spintronics for more than 15 years. He holds a Physics degree from Babes Bolyai University in Cluj (Romania) and a PhD in Physics from Louis Pasteur University in Strasbourg where he pioneered the work on magnetic nanostructures. He then joined SPINTEC research laboratory in Grenoble, where he pioneered scientific work on thermally assisted MRAM, tackling the key long-standing problem of bits stable enough for long-term storage, yet still easy to write with small magnetic fields. Based on this proof-of-principle of the scientific concepts, Crocus Technology was founded in 2006 to develop and commercialize thermally assisted MRAM technology. Lucian joined Crocus Technology mid-2006 as R&D manager, where he made key contributions to the development and industrialization of thermally assisted MRAM for which he was awarded the SEE-IEEE Brillouin prize in 2012. In 2013, Lucian returns to Spintec as deputy director and became executive director as of January 1st, 2016. He holds 38 international patents on magnetic memories and has authored more than 70 scientific publications and book chapters on nanomagnetism and spintronics.

January 2016 –: Executive Director, SPINTEC

February 2013 – December 2015: Deputy Director, SPINTEC
• Daily management of the laboratory (HR, finances, HCERES evaluation)
• Management of the sensors team
• Management of the R&D Crocus – Spintec research program (MRAMs & magnetic sensors)
• Setup and managed several R&D projects: ANR Excalyb, joint spintronic line SPINTEC / LETI
• Engineering of high sensitivity 3D magnetic sensors
• Engineering of magnetic tunnel junctions for industrial MRAMs and MLU (magnetic logic unit) - Led
• Material development for advanced MRAM – thermally assisted with field or spin polarized current writing, self-reference
• Concept for magnetic logic unit applications

August 2006 – January 2013: R&D Manager, Crocus Technology
Management and expertise of magnetic materials for thermally assisted or STT-MRAMs
• Engineering of magnetic tunnel junctions for industrial MRAMs and MLU (magnetic logic unit) - Led material development for advanced MRAM – thermally assisted with field or spin polarized current writing, self- reference concept for magnetic logic unit applications
• Management of the R&D Crocus – Spintec research program
• Management of the installation of a back-end magnetic processing line 200mm: deposition / magnetic anneal / characterization
• Established the initial company wafer level test-chip design
• Participated in company’s early stage of strategic business development & planning
• Built up intelligent monitoring scheme to diagnosis wafer processing defects at early stages, enabling high yields for product environment
• Setup and managed several R&D projects: TIMI, R&D Crocus – INESC, ANR RAMAC, CRYSTO, CILOMAG, SPIN, PATHOS
• Demonstrated the TA-STT concept
• Demonstrated the self-reference cell writing adapted for logic applications and improved performances MRAM

December 2004 – July 2006 : CEA/INAC engineer, SPINTEC, Grenoble
MRAM technology advisor for the fund raising and the creation of Crocus Technology
Magnetic logic: based on extraordinary Hall effect & using domain wall movement in magnetic structures with perpendicular magnetization
Magnetic storage: STT based writing based from a near field nanometric tip
• expert OMNT in nanomagnetism & spin electronics
• editor of a special edition of J. Phys. C : Cond. Mat, dedicated to the spintronics
• Setup an EU RTN project: SPINSWITCH

April 2003 – November 2004: Postdoc CEA/INAC, SPINTEC, Grenoble

Thermally assisted MRAMs: first demonstration of the thermally assisted MRAMs with an exchange biased storage layer
• Design and engineering of magnetic tunnel junctions, caracterisation, optimisation of structural, electrical & magnetic properties
• Management of a R&D contract with CYPRESS SEMICONDUCTEUR
• Management of the ANR contract ECRIN (thermally inhibited memories with ferrimagnetic storage layers)

March 2002 – March 2003: Postdoc CNRS, Louis Néel laboratory & SPINTEC Grenoble
Magnetic storage: patterned media and writing by heating the dots by a near field nanometric AFM tip
• Conception and development of the experimental setup: injection of spin polarized current
• Fabrication of submicronic dots by e-beam and UV litography and dry etching
• Macroscopic magnetic characterization (Kerr, VSM), magnetic microscopy (MFM)

November 1998 – February 2002: PhD, IPCMS (Institut de Physique et Chimie des Matériaux de Strasbourg)
Nanomagnetism, spin electronics: domain wall magnetoresistance in nanowires & effect of dipolar interactions on the reversal of the magnetization
• Fabrication of nano-objects by e-beam lithography
• Magnetotransport measurements magnetic microscopy MFM, micromagnetic simulations;
• Local coordinator of the european contract MAGNOISE

October 1997 – November 1998: R&D engineer, INCDTIM 
National institut for research & development of the isotopic and molecular technologies, Cluj-Napoca, Romania

Molecular Physics: multi-fotonic dissociation of molecules in laser radiation field

March 1997 – July 1997: Master of Science, LMGP
Laboratoire de Matériaux et de Génie Physique - INPG Grenoble

Refractory materials: low temperature preparation of ultra-refractory nanocompounds
• Structural characterization: X-ray & electronic microscopy

March 1996 – June 1996: Bachelor of Science 
Institut de recherche en physique de l’Université Babes Bolyai, Cluj Napoca, Roumanie

NdFeB permanent magnets: preparation & magnetic caracterisation

Training and diploma
2005: Habilitation (Grenoble INP, Grenoble)
2001: PhD in physics – condensed matter & materials
Louis Pasteur University & Institut de Physique et Chimie des Matériaux de Strasbourg

1998: Master of Science - condensed matter & materials
Babes-Bolyai University, Cluj-Napoca, Romania & INPG Grenoble

1997: Bachelor in physics - condensed matter & materials 
Babes-Bolyai University, Cluj-Napoca, Romania

Publications & Patents
Published over 70 papers in scientific journals & chapters in scientific books (Springer Verlag, NATO Science Series) - H-index: 18
Holds 39 patents filed, at different stages (granted, published, provisional pending)

General context of my work
The research of new approaches to making non-volatile memories has been a major activity of SPINTEC since its inception. SPINTEC research laboratory was established in 2000 to specifically work at valuation of upstream work in the areas of nanomagnetism and spintronics. The MRAM team in SPINTEC has proposed alternative MRAM technologies with improved performances (speed, scalability and power consumption) and avoiding problems like the write selectivity, power consumption, electromigration and thermal stability at high densities. Multiple approaches have been pursued in parallel:
• Thermally-Assisted Switching (TAS), as developed by our spin-off Crocus Technology which has been refined by constant materials improvements and for which lately multi-level storage has been demonstrated in a “Magnetic Logic Unit” (MLUTM).
• Spin Transfer Torque (STT), which has been improved by reducing the critical switching current and/or allowing reversible switching with a unipolar current.
• The combination of TAS and STT, which has been revisited for perpendicular magnetic tunnel junctions (viewed as the future of STT MRAM) in a new concept dubbed Thermally-Induced Anisotropy Reorientation (TIAR) which provides industry-record writing efficiency.
• Precessional switching (also known as Orthogonal Spin Torque - OST), which was initially proposed by Spintec in 2001 and has been finally demonstrated, fulfilling its promises of ultimate speed.

Spintec has been amongst the pioneers in MRAM development and is recognized worldwide as such. Consequently, we have / have had multiple partnerships with laboratories, research centers and companies, through joint R&D projects (ANR, EU), as well as bilateral industry partnerships. A preferred relation exists with Crocus, which led to the onset of a 5 years “joint laboratory” signed in 2013.

Based on patents filed between 2001 and 2005, a new technology of non-volatile magnetic memories, thermally assisted has been demonstrated by Spintec. The originality of this technology stems from the specific writing process that combines a short heating pulse sent through the memory cell (few nanoseconds) with a magnetic field pulse or a spin polarized current. The very convincing results obtained by SPINTEC and LETI in the framework of the NEXT European project between 2001 and 2005 enabled the launch of a start-up Grenoble, Crocus-Technology, which has managed to raise 13.5 Million Euros from venture capitals in 2006. This transaction also received the grand prize of the ANVAR innovation in 2005 and was a finalist EU Descartes Prize in 2006.

Since the first demonstration of the TAS-MRAM concept in 2004, several improvements / variations of this technology have been proposed:
The concept of heat assistance can be advantageously coupled to writing by spin-polarized current to significantly improve the thermal stability in STT-based systems. The use of spin transfer as writing means offers much better prospects for decreasing sizes than writing magnetic field. Indeed with the spin transfer, the write current decreases as the cell size while in the field writing, the write current rather tends to increase as the size decreases. However, the STT-RAM suffers from the same problem as the MRAM standards in terms of thermal stability for small sizes. TA-STT-RAM concept (Thermally Assisted Spin Transfer Torque RAM) allows to ensure higher MRAM densities while minimizing the write current. In this concept, the same current flowing through the tunnel junction makes heats by Joule effect and exerts magnetic torque by spin transfer torque phenomenon. The concept of TA-STT-RAM was developed within the framework of a bilateral agreement between CEA and Crocus and a ANR 2007 "RAMAC," (Technology Roadmap for Advanced MRAM).
Recently, the joint R&D teams from Crocus in Spintec developed a self-referenced reading concept which now serves as building block for the company's products. This new concept makes the memory much more tolerant to process variations and very promising for security applications (smart cards, routers, biometrics). Technological advances have enabled obtained Crocus growing dramatically, as evidenced by one of the latest fund-raising 300M€ in 2011 enabling him to go live with one of the first full magnetic back-end fab worldwide.
In addition, the research work carried out in close collaboration with SPINTEC allowed several advances at the highest international level of research on MRAM: the ultra-low power memories combining writing to the local heating spin polarized current TAS-STT of systems with perpendicular anisotropy.