17.10.2012 1 2012 Aerosol Jet International User Group Meeting Metallization and Functional Structures by Aerosol Jet deposition Andreas Brose Institut für Mikro- und Sensorsysteme Lehrstuhl Mikrosystemtechnik
2 Introduction Otto von Guericke University Magdeburg Institute for Micro and Sensor Systems (IMOS) Chair of MEMS Technology MEMS MID Reliability
3 Facilities R & D Design and Simulation lab (30m 2 ) MEMS MEMS-cleanroom (class: 100, 150m²) Packaging Packaging labs (72m² + 100m²) Reliability Reliability lab (50m²)
4 3D-MID activities Equipment 1&2-shot injection molding LDS/Hot embossing/aerosol- Jet deposition PVD/Galvanic/Electroless Plating Soldering/Wire Bonding/Flip- Chip electric characterization with environment simulation X-ray Analysis Services Consultation/Conceptual Design Simulation/CAD Prototyping/Pilot Run Testing & Qualification Research MEMS on MID Reliability of Chip on MID/Flex Product Miniaturization by MID Medical MID Systems MID Sensor Structures
5 Pattern generation additive subtractive masked processes maskless processes Screen printing Stencil printing Thin film processes Inkjet Aerosol Flamecon Metallization Nano particle inks Catalytic seed layer (MicroCat) Passivation / Isolation (non conductive) Function materials (resistors, piezoelectric, medicals, )
6 Aerosol Jet System @ IMOS Aerosol generation deposition head camera moving stage
7 Overview: applicated inks Nano particle based inks - Silver, Gold, Platinum, Copper Catalytic ink (MicroCat) - Seed layer for additional plating processes Function- and isolation layers - Dielectrics (adhesives, resists), Piezoelectrics (PZT) Sintering necessary Layer thickness < 1µm Electroless plating of Cu/Ni/Au No thermal treatment Viscosity up to 1000cP Particle size up to 500nm
8 2D-metallizations RF-resonant circuit Silver on glass (Pyrex) Gold electrodes on MEMS-Chip Platinum electrodes on Langasite (LGS) micro cantilever
9 3D-metallizations cooling device for high-power LED module Silver deposition on ceramic heat sink (AlN) challenge: covering the edges
10 3D-metallizations Copper issues: difficult wetting behavior heating substrate and ink insufficient jetting stability improvable conductivity cooling device for high-power LED module nano-copper ink (Intrinsiq Materials, Inc) sinter process: laser sintering (Nd:YAG)
11 Catalytic ink process flow Aerosol Jet deposition of catalytic ink - contains Palladium, 2component-adhesive, organic solvent Drying step Activation by reducing agent Electroless plating of - Copper/Nickel (NiP)/Gold Low temperature process no sintering good conductivity solderable surface noncorrosive
12 Antenna on 3D-MID 4 working planes continuous pattern
13 Reliability testing measuring and comparing the shear strength of SMDs mounted on MID-substrates metallization by aerosol deposition of catalytic ink LDS-metallization
14 Catheter marker for MR imaging insufficient contrast between polymer catheter and human tissue minimal invasive surgery requires new tools for better imaging Idea: local amplification of magnetic field with resonant circuit at the catheter tip 1st discrete version: coiled copper wire and SMD capacitor Objective: integration by Aerosol Jet metallization
15 MRI-Marker for catheter devices printed helix with catalytic ink electroless plating loose coupling with measure coil return loss S 11
16 MRI-Marker Multi layer layout metal 1: Cu (electroless plated) dielectric: PET heat shrink tubing metal 2: Cu/Au (electroless plated) C L
17 Validation with 3T-MRI Working Markers provide positive image contrast Positive contrast enables computerassisted tracking
18 3 Tesla-MRI installed at University of Magdeburg in September 2012 Only for scientific use!
19 Function materials Passivation layers - Selective deposited protective coating for encapsulation of SMD components PZT-layer on silicon membrane - PZT-powder containing suspension (95% of the particles < 300nm) - average layer thickness: 3µm - sintering at 600 C
20 Function materials X-ray analysis: permittivity layer thickness (µm) Permittivity of Aerosol Jet deposited PZT film higher than screen printed and electrophoretic deposited films X-ray analysis showed inhomogeneous film thickness
21 Aerosol coating of CMUT-gas sensor 0.2 mm 2.6 mm single element membrane cavity substrate In cooperation with chair of measurement and sensor technology at OvGU
22 Aerosol coating of CMUT-gas sensor Multi-channel CMUT coated with various sensing materials - Enables sensor array to analyze gas mixtures Coating materials: Material Abbreviation State Solvent Solvents BP ( ) Concentration (mg/ml) Methyl-β-Cyclodextrin β-cd Solid Ethanol 78.4 3 or 6 4-tert-Amyl-Calix[8]arene CA Solid Chloroform 61.2 0.5 Polyethylenimine PEI Liquid Water 100 1.5 Cyanopropylphenyl Dimethylpolysiloxane OV 225 Liquid Polydimethylsiloxane PDMS Liquid Ethyl acetate Ethyl acetate 77.1 3 77.1 3 In cooperation with chair of measurement and sensor technology at OvGU
23 Aerosol coating of CMUT-gas sensor Coffee ring dropping with micro pipette Advantages: Aerosol Jet coating precise patterning controllable output volume thin and uniform layers In cooperation with chair of measurement and sensor technology at OvGU
24 Contact Andreas Brose Otto-von-Guericke-University Magdeburg IMOS Phone: +49 (0) 391 / 67-58227 Fax: +49 (0) 391 / 67-12609 email: andreas.brose@ovgu.de