What are these mysterious structures on wireless chipsets?

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SUMMARY

The discussion centers on the analysis of structures found on wireless chipsets, specifically identifying them as interdigital capacitors and spiral inductors. The substrate material is likely glass (SiO2), and these structures are standalone planar circuits connected to a ground plane, differing from standard silicon integrated circuits. The conversation highlights the complexity of fabricating these components at scale, emphasizing their unique characteristics compared to traditional silicon RF ICs.

PREREQUISITES
  • Understanding of wireless chipset architecture
  • Knowledge of RF circuit components, specifically interdigital capacitors and spiral inductors
  • Familiarity with materials used in semiconductor fabrication, particularly SiO2
  • Basic principles of planar circuit design
NEXT STEPS
  • Research the fabrication techniques for glass substrates in semiconductor manufacturing
  • Study the design and function of interdigital capacitors in RF applications
  • Explore the role of spiral inductors in wireless communication systems
  • Investigate the differences between planar circuits and traditional silicon ICs
USEFUL FOR

Electrical engineers, RF circuit designers, and semiconductor manufacturing professionals interested in the intricacies of wireless chipset structures and their applications.

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...