bio compatible microsystem packaging of vcselaser for ... · pdf file03/03/2013 ·...

Bio‐Compatible Microsystem Packaging of VCSELaser for Implantable Devices

Dr Alexander Steinecker, CSEM, Alpnach (CH)

EPoSS Annual Forum, Torino (IT), 25.09.2014


The miracle of hearing


Cochlear Implants ‐ a technical masterpiece

Source: www.medel.com


Cochlear Implants – Background

• Areas in cochlear correspond to acoustic frequency

• Degradation of sound transmission in the inner earcan be bridged

low frequencies(< 100 Hz)

high frequencies(> 10 kHz)


Limitations of electrical stimulation

Source: Clark G. The multi-channel cochlear implant: past, present and future perspectives. Cochlear Implants Int. 2009;10 Suppl. 1:2-13

• Very sensitive local frequency responsewithin cochlear, mismatch acoustic vs. Electric hearing

• From one to four electrodes rapid improvement achieved, above 4‐20 nodetectable advantage

• Nerve Cell tissue damage due to directhigh current stimulation density

• Poor spatial resolution with electricstimulation


Advantages of opto‐acoustical stimulation

• Laser pulses in water generate acoustic signals – «Optophony»

• Spectral response enables high temporal and frequency selective stimulation

Telecom VCSEL


EU Project STREP‐ICT FP7 ACTION ‐

Project Reference EU 611230 STREP ICT‐2013.3.3

Enhance hearing experience forseverely impaired patients byeliminating limitations in spatial and temporal excitation of cochlearimplants based on electricalstimulation

ACTive Implant for OptoacousticNatural sound enhancement


Overview of innovation areas in optical cochlear device


Key technology components for optical stimulation


Optical Cochlear Microsystem I – Packaging ‐ Housing

State of the art: Biocompatible housingmaterials Ti, Ta

Drastic size reduction (<800µm dia), hermetic enclosure with low temperature sealingprocess (<250°C for few seconds)

1mm Transparency in IR range


Optical Cochlear Microsystem II – Packaging ‐ Connections

State of the artfeedthrough 4mm width

hermetic low temperature sealing with approved long term biocompatible materials (ceramics and highly biocompatible metals such as Nb, Pt, Ti)


Optical Cochlear Microsystem III – Biocompatible Sapphire Lens

Sapphire lens for high biocompatibility

Plasma reactive ion etching (RIE‐ICP) only manufacturing option for micro‐optics in sapphire on Wafer Level


Optical Cochlear Microsystem IV – VCSEL arrays

Parameter ValueLaser array 10 x 10Wavelength 1400 – 1900 nmPeak output power > 20 mWOperating range 20 – 45 oCDrive current <30 mA

Long wavelength VCSEL with superiorperformance for 1.3 μm < 2.3 μm

optimized for maximum efficiency at human body temperature


Optical Cochlear Microsystem V ‐ Biocompatible flex circuit (ST Microelectronics/CSEM)

• Flex circuit

• Platinum, Niobium, Tantalum, Biocompatible polymers

• Highly flexible

• Chip on wire technology

• Chip integrated directly on wire

• High throughput


Leading edge European Medical device manufacturing

MiniaturizationAdvanced Long WavelenthVCSEL Laser

BiocompatibleFlexprint

Low temperaturebiocompatible

hermeticenclosure

Biocompatiblemicrolens at wafer scale

Semi‐automaticsmall scalepackaging


Thanks to our cooperation partners and funding bodies!

Reference:“James, R.Jose, Low Temperature Hermetic Sealing for Implantable Medical Systems, 2010”R.Jose James, CSEM SA

This project is supported by the EU Commission, the European Research Funding organisation under FP7 STREP ICT‐2013.3.3 Program Grant No. 611230

bio compatible microsystem packaging of vcselaser for ... · pdf file03/03/2013 ·...

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