Thank all of you for your replies to my question on the mems height record. In
view of the volume of responses and to avoid my clogging up your mail-boxes
unnecessarily while answering those who were kind enough to reply, I thought
I'd try a group reply.

In reading the responses, I realise I did not phrase the first sentence and the
question well. My research interest is, at this point, in mems array structures
that have controllable motion out-of-the-plane. I really am interested in
height combined with lateral motion. Most folks told me about height but not
about lateral motion. Mems I took to mean fabricated by a lithographic process
and not by post-fab assembly. I guess I have a narrow-minded definition but "
'tis mine own", though I respect those who are striving for a more precise
definition.

The LIGA process though excellent technology for thick structures such as shown
in those beautiful gears does not, as far as I know, allow structures with
motion orthogonal to the plane of the wafer (although I suppose you could tilt
the gears relative to a base plane).

Assembly of spikes of the same or dissimilar material, like the "glop" idea,
sounds terrific and I thank you for making me look at the process in a new way.

Devices that overhang the chip don't really apply because, to make a
two-dimensional array they would have to be sliced up and assembled on edge
precisely; which would be real tough to do.

In summary, I received a lot of interesting replies that are causing me to read
further and differently and for that I thank you all.

Peter Will