Cosmic Autumn School, 2012, Munich, Germany
INTERFLEX
Interconnection Technologies for
Flexible Systems
Metin Koyuncu
Robert Bosch GmbH
Corporate Research, Waiblingen, Germany
www.project-interflex.eu
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Interflex Project Consortium | 20.11.2012 | © Robert Bosch GmbH 2011. All rights reserved, also regarding any disposal, exploitation,
reproduction, editing, distribution, as well as in the event of applications for industrial property rights.
Cosmic Autumn School, 2012, Munich, Germany
Interconnection Technologies for Flexible Systems
Call:
ICT-2009.3.3 b) Flexible or foil-based systems
Funding scheme:
STREP
Proposal Acronym: Interflex (www.project-interflex.eu)
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Duration:
36 Months
Project start:
01.01.2010
Interflex Project Consortium | 20.11.2012 | © Robert Bosch GmbH 2011. All rights reserved, also regarding any disposal, exploitation,
reproduction, editing, distribution, as well as in the event of applications for industrial property rights.
Cosmic Autumn School, 2012, Munich, Germany
Project Objectives
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Development of reliable assembly and interconnection technologies
for foil based electronic systems:
 Interconnection technologies between flexible components and
flexible foils as well as between functional foils.
 Three dimensional functional foil integration to achieve multi-foil
based systems, i.e. system-in-foil.
Demonstration of the developed technologies with an energy
autonomous, indoor air quality sensing system, capable of
wireless communication of the measured data.
 Bendable to a bending radius of ½ its maximum dimension
Interflex Project Consortium | 20.11.2012 | © Robert Bosch GmbH 2011. All rights reserved, also regarding any disposal, exploitation,
reproduction, editing, distribution, as well as in the event of applications for industrial property rights.
Cosmic Autumn School, 2012, Munich, Germany
System-in-Foil
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Hardware based on flexible foil substrates,
flexible components and compatible
interconnects, that offers a high functional
integration, high packaging density and
mechanical flexibility.
Integration of components onto the foils
and foil-to-foil integration plays a key role
in the realisation of a system-in-foil.
System-in-foil offers a high potential for
seamless integration of electronics onto
non-planar surfaces and everyday objects.
Interflex Project Consortium | 20.11.2012 | © Robert Bosch GmbH 2011. All rights reserved, also regarding any disposal, exploitation,
reproduction, editing, distribution, as well as in the event of applications for industrial property rights.
Source: Holst Center
Cosmic Autumn School, 2012, Munich, Germany
Interconnection Technologies for a System-in-Foil
Energy
Battery
Photovoltaics
Power management
Sensing
IC
WL
µC
IC
CO2
Dew
R.H.
T
Sensors
Tx
Communication
Antenna
Wiring Layer (Printed Circuit Foil)
IC: Integrated Circuit
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Lamination
www.project-interflex.eu
µC: Microcontroller
Interflex Project Consortium | 20.11.2012 | © Robert Bosch GmbH 2011. All rights reserved, also regarding any disposal, exploitation,
reproduction, editing, distribution, as well as in the event of applications for industrial property rights.
Cosmic Autumn School, 2012, Munich, Germany
Components of a System-in-Foil
Component
Type
Components
Integrated Circuit
Bare Die (<50µm)
Foil Component
Battery, Solar cell, Sensors,
OTFT, OLED
Wiring Layer /
Printed Circuit
Foil
SMDs
Foil with already integrated
foil components:
“heterogeneously” and/or
“homogeneously”
Discrete transistor,
capacitor, quartz, inductor,
resistor
SMD: Surface Mount Device
OTFT: Organic Field Effect Transistor
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Thinned Silicon Wafer
OLED:
SMD:
Thin Film Battery
Flexible PV array
Sensor Array on Foil
Organic Light Emitting Diode
Surface Mount Device
Interflex Project Consortium | 20.11.2012 | © Robert Bosch GmbH 2011. All rights reserved, also regarding any disposal, exploitation,
reproduction, editing, distribution, as well as in the event of applications for industrial property rights.
Flexible Sensors
Cosmic Autumn School, 2012, Munich, Germany
Schematic Layout of the INTERFLEX Demonstrator
Via connections
PEN / 50µm
PI / 50µm
PI / 50µm
SMD
(PEN / 50µm)
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Energy autonomous air quality monitoring system with wireless data
transfer capability.
WL: Wiring Layer (Printed Circuit Foil)
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Interflex Project Consortium | 20.11.2012 | © Robert Bosch GmbH 2011. All rights reserved, also regarding any disposal, exploitation,
reproduction, editing, distribution, as well as in the event of applications for industrial property rights.
Cosmic Autumn School, 2012, Munich, Germany
Layout – INTERFLEX Demonstrator
WL2 top side
WL1 top side
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Interflex Project Consortium | 20.11.2012 | © Robert Bosch GmbH 2011. All rights reserved, also regarding any disposal, exploitation,
reproduction, editing, distribution, as well as in the event of applications for industrial property rights.
WL1 bottom side
Cosmic Autumn School, 2012, Munich, Germany
Integration of Foil Components
Video camera
flexible in x/y
direction
Magnetic
holder
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Wafer frame carries foil
componet to be placed
Vacuum chuck
adjustable in
x, y, ϕ direction
• aligned lamination of 2 WLs with
identical copper pattern
• determination of shift between
top to bottom WL in x/y-direction
@6 positions
• misalignment in x/y-direction
better than 100μm
Interflex Project Consortium | 20.11.2012 | © Robert Bosch GmbH 2011. All rights reserved, also regarding any disposal, exploitation,
reproduction, editing, distribution, as well as in the event of applications for industrial property rights.
Cosmic Autumn School, 2012, Munich, Germany
Foil-to-Foil Electrical Integration
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Interconnection between WLs
Mechanical Integration ensured by
adhesives, e.g. PSA
Electrical interconnection via
conductive adhesive or conductive ink
Jetting of conductive paste or ink
Screen printing conductive paste
Good mechanical resistance to bending stress
Jet
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Foil Component
Wiring Layer
Examples of via filled with conductive adhesive
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WL: Wiring Layer
PSA: Pressure Sensitive Adhesive
ACF: Anisotropic Conductive Film
Interflex Project Consortium | 20.11.2012 | © Robert Bosch GmbH 2011. All rights reserved, also regarding any disposal, exploitation,
reproduction, editing, distribution, as well as in the event of applications for industrial property rights.
Cosmic Autumn School, 2012, Munich, Germany
Process Challenges
Integration of diverse
components from 0.5 mm2
Si-ICs to 3000mm2
photovoltaic arrays onto
wiring layers.
Flexible PV array
• Variety of surfaces and materials (metal,
plastic) to be electrical and mechanical
contacted/connected
• Overall thermal budget limited
Flexible humidity sensor
Handling of flexible and
diverse components
 Entire assembly process
in one equipment?
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Mechanical and
electrical contacts
between foils by
3D-Integration.
Interflex Project Consortium | 20.11.2012 | © Robert Bosch GmbH 2011. All rights reserved, also regarding any disposal, exploitation,
reproduction, editing, distribution, as well as in the event of applications for industrial property rights.
Cosmic Autumn School, 2012, Munich, Germany
Applications
Source: Adidas
Source: Holst Center
Source: Sensimed
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•Smart clothes
•Wellness and healthcare patches
•Medical applications
Interflex Project Consortium | 20.11.2012 | © Robert Bosch GmbH 2011. All rights reserved, also regarding any disposal, exploitation,
reproduction, editing, distribution, as well as in the event of applications for industrial property rights.
Cosmic Autumn School, 2012, Munich, Germany
Summary
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System-in-foil offers
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Very high functional integration
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Very high packaging density
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High potential for seamless integration into everyday life
Interaction between system designers, component developers and
processing has to start at a very early stage
Further research effort necessary for integration of SMDs, e.g.
passive components
Application oriented research with interdisciplinary collaboration
is essential
Interflex Project Consortium | 20.11.2012 | © Robert Bosch GmbH 2011. All rights reserved, also regarding any disposal, exploitation,
reproduction, editing, distribution, as well as in the event of applications for industrial property rights.