Nano- & Micro-Joining
The continuing trend of heterogeneous integration (i.e. miniaturization, diversification and functionalization) requires novel joining concepts to integrate, package and assemble micro- and nano-scale devices at ever-lower temperatures, flux-free, pressureless and with ever-higher alignment accuracies. To address these industrial demands, we conduct research on nanostructured filler materials, such as nanomultilayers and nanopaste, targeting at the utilization of nanoeffects (e.g. interfacial premelting, directional short-circuit diffusion) for novel nano-/microjoining technologies. Our lab is renowned for its pioneering work on the development of nanostructured brazing fillers with patterned liquid metal outflow and reactive nanomultilayers for room-temperature joining processes (→ our services). As founder member of the International Association for Nano- and Microjoining (NMJ), we are actively shaping the field of Nano-/Microjoining as a new scientific discipline and technology (see: www.nmj.org).
OUR RESEARCH
- Design and synthesis of product-tailored nanopaste formulations and nanothermites through wet chemical synthesis routes.
- Design and synthesis of nanostructured brazing fillers with tailored nanolayer thicknesses, interface structures and residual stresses by physical vapor deposition techniques.
- Development of new joining procedures for integrating, packaging and assembling micro- and nano-scale devices
- Thermodynamics and kinetics of nanopaste sintering, diffusion bonding and competing interfacial phase formation in nanostructured materials (e.g. nanomultilayers, nanothermites and nanopastes) during manufacturing and subsequent operation (→ Advanced Joining)
- In-situ monitoring of reactions, phase transformations and stress evolutions at heterointerfaces in nanostructured joining materials by laboratory- and synchrotron-based techniques (e.g. XRD, XPS/HAXPES, TEM, SEM)
SELECTED PUBLICATIONS
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Empa NEWS - "With nanoeffects towards new joining processes"
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Joining Technology Innovations at the Macro, Micro, and Nano Levels
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Al-Si/AlN nanomultilayered systems with reduced melting point: experiments and simulations
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Tailoring Fast Directional Mass Transport of Nano-Confined Ag–Cu Alloys upon Heating
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Reactive Joining of Thermally and Mechanically Sensitive Materials
nanojoining, mirojoining, packaging, micro assembly, flip-chip bonding, die bonding, nanobonding, reactive joining, nanopaste, nanoparticle, nanomultilayers, nanothermite, coating, foil, sintering, wetting, stress, melting point depression, nano-joining, micro-joining
nanojoining, mirojoining, packaging, micro assembly, flip-chip bonding, die bonding, nanobonding, reactive joining, nanopaste, nanoparticle, nanomultilayers, nanothermite, coating, foil, sintering, wetting, stress, melting point depression, nano-joining, micro-joining
Metallography Userlab
The Empa Metallography Userlab provides know-how and facilities for sample preparation using conventional metallographic methods (e.g. cutting, grinding and polishing). Access to the lab is granted to all registered Empa employees, which have completed a general safety course and also received a personal instruction to the rules and safety aspects of the Userlab (see below). Please note that the Metallography Userlab is not a service center, i.e. we do not offer (routine) sample preparation tasks.
We provide the following facilities for metallographic sample preparation:
- Cutting machine AbrasiMet 250
- Precision cutting machine (Buhler IsoMet4000 )
- 40mm diameter hot mounting press (Buhler SimpliMet 1000)
- Grinding Machine (Buhler MetaServ 250)
- 2 semi-automatic polishing machines (Buhler PHOENIX 4000 / EcoMet 250)
- Vibration polishing (Buhler Vibromet 2)
- Optical microscopes with Camera (Zeiss Axiovert 100A / Stemi SV 11)
The following consumables for sample preparation are provided by the UserLab in reasonable quantities:
- Standard cut-off wheels (note: diamond cut-off wheels are not provided by the UserLab)
- Hot- and cold-mounting resins (incl. clamps and other tools)
- Grinding Paper (FEPA 80-4000)
- A common stack of polishing cloths (note: individual sets are not financed by the UserLab)
- Commonly applied polishing suspensions and lubricants
- Basic chemicals and equipment for standard etching solutions
Support with guidance and assistance regarding sample preparation and interpretation is available.
The usage of the Metallography Userlab is accessible for authorized personnel only. Please follow the process How to register, see below.
GENERAL RULES FOR USAGE
- The Metallography Userlab is available for authorized (registered) personnel only
- It is accessible to work Mon-Thu 8.00-16:30 h (before public holidays -15:30 h), support until 15.00 h, Fri 8:00-16:00 h, support until 12:00 h. The lab is closed during the weekend and public holidays.
- After the use your activities and times must be noted in the lab list
- Equipment and facilities have to be cleaned after use
- Use the provided consumables in an economical way
- Leave a note if consumables are running low on stock or if the equipment is damaged or broken
- Working with fluoric acid or chemicals, which contain fluoric acid, is only allowed if a special chemical safety course was attended (please contact )
HOW TO REGISTER
- Please fill in the registration form and let it sign by the indicated responsible persons. Note: Digital signing only works if the Pdf is opened in Adobe Acrobat (first save and then open it in Adobe Acrobat)
- Bring the completed and signed form along to the introduction (it will be signed by the Userlab Responsible)
- For an introduction please contact A. Lau (alexandra.lau@empa.ch)
The Metallography Userlab is accessible for registered users to work during the following times:
Monday-Thursday: 08:00-16:30 h (15.30 h before public holidays), support until 15.00 h
Friday: 08:00-16.00, support until 12:00 h
The lab is closed during the weekend and public holidays!
