What are these mysterious structures on wireless chipsets?

AI Thread Summary
The discussion focuses on the identification of mysterious structures found on wireless chipsets after careful decapsulation. Observers note that the substrate material appears to be glass (SiO2) and that the structures are not typical top layers of standard silicon integrated circuits, but rather standalone planar elements connected to a ground plane. Key features identified include an interdigital capacitor and a spiral inductor, suggesting these structures function as circuit elements. The unique planar design indicates they are not capacitively coupled to other components, differing from traditional silicon RF ICs. The conversation highlights the complexity and precision required in their manufacturing.
Andy Resnick
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Careful decapsulation of wireless chipsets results in these structures:

http://imageshack.us/a/img690/7145/9yd4.jpg

http://imageshack.us/a/img854/7783/kq3i.jpg

http://imageshack.us/a/img850/3041/xxki.jpg

http://imageshack.us/a/img826/2589/easq.jpg

I'm hoping someone can provide clues/insight as to what these are. The substrate material is likely glass (SiO2), about as thick as a MEMS cantilever, and are generally not top layers of a 'standard' Silicon IC- they are stand-alone planar structures connected to a ground plane (not shown).

Thanks in advance...
 
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Difficult to tell.
The structure on the 3rd picture is a (or perhaps more than one ) interdigital capacitor. At the bottom of the 4th image I can also see a spiral inductor.
 
Right- I can recognize certain circuit elements from similar features on silicon RF ICs. On those silicon ICs tho, the coils etc. are just the top layer. These aren't capacitatively (is that a word?) coupled to anything- it's truly a planar circuit.

Never mind the manufacturing magic needed to fabricate a zillion of these every second...
 

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