MEMS Process Engineers

Micro-Electrical- Mechanical-Structures (MEMS) Process engineers

MEMS devices are manufactured using many of the techniques used for Silicon processing; Lithography, Reactive Ion Etching, Deposition, etc. and all these steps occasionally need qualification. Our MEMS process qualification service ensures that the structures are the correct shape (X,Y and Z) and have the right edge profiles. In addition to these ‘standard Silicon processing problems, MEMS devices also use techniques that are specific to their fabrication. Many mechanical structures are fabricated in a stack and then 1 layer of that stack is removed chemically to effectively disconnect that structure from the substrate. Our advanced FIB lab can accurately assess and analyse each layer of your MEMS device to correctly identify where your process is not producing the results you desire.

Understanding the cause of process or functional failures requires the application of various microscopy techniques to site specific locations.

Whether your needs are simple metrology or a more detailed high resolution analysis, both can be delivered from the required location using the nano-sectioning capabilities of FIB. Applying SIM, SEM and TEM, all enabled with FIB, our MEMS process qualification service can help you understand your device structure and any failure modes.

NanoScope’s fast turn-around ‘off the shelf’ expert service, makes this available at every level of MEMS process development.

The example below shows simple 3D structural metrology of a wave guide at a specific point.

FIBxTEM section preparation from MEMS ‘cog’ (foil width ~20um)

In this example we can see a cog structure and for this to be able to turn it must be disconnected from the Silicon below it, and the liquid solvent used to dissolve its connection needs to be able to flow underneath it, and also to escape from underneath it this process is finished. To enable this a series of drain holes has been added to the structure, and checking that these are free and clear of obstruction is fundamental to the successful processing of this device.

Waveguide metrology – within a FIB milled section (result time 20 mins)

In this image we have cut a cross-section through this drain hole to show its internal structure for the purposes of qualifying the fabrication process and ensuring good etchant flow, in and out of the structure.