Home

WP1 Metalisation

WP2 Connection

WP3 Amplifier 

WP4 Stimulation

WP5 Fabrication

WP6 Assembly

WP7 Models

WP8 Global System

Description

Achievement

For IMANE, AML have developed a wafer level packaging technique suitable for long-term human implantation.

The package shown in the diagram below is based on through wafer interconnects powderblasted through Pyrex or silicon and hermetically filled with Gold (bottom-up electroplating).

Assembly scheme

Vias can be made in 'carrier' wafers or CMOS device wafers, but 'carrier' wafers are preferred since they enable Chip to Wafer (C2W) packaging with chips from multi-project wafers (MPW's).

In the C2W approach used for IMANE, CMOS chips are fabricated on multi-project wafers, gold bumped and then bonded directly to the solid gold through wafer interconnect vias.

The bumped chip, Pyrex carrier wafer and vias are shown in the photograph.

ASIC and TSVs

An anodic wafer to wafer bond seals chips within hermetic cavities.

The wafer-level package is completed by selectively welding layers of PDMS and patterning platinum sensor circuitry to complete the smart system

Finally the package is diced by AML, and individual devices (9 per wafer) released.

Applications

The techniques developed by AML are applicable across a broad range of applications.  The powderblasting technique applies to Silicon, Pyrex, Quartz, GaAs etc, and uses low cost materials and low manufacturing overheads (processing is outside a cleanroom).

An implantable hermetic wafer level packaging technique suitable for C2W applications has significant benefits for low volume and R&D applications and situations where off the shelf sensors, MPW's, or stacked die are used (e.g. ASIC + MEMS devices).

The techniques developed for IMANE have also been applied to other implantable devices, SAW sensors (Quartz packages) and sensors for harsh environments.