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Materials for thin-film capacitors
Thin-film capacitors are single layer metal-insulator-metal (MIM) capacitors are formed by thin-film processes. Examples include most capacitors on MMICs. It is possible to form MIC capacitors on ceramic thin-films, but the rough surface of the ceramic means a world of hurt for yield (potential pin-holes) so we don't recommend it! Here's just a few dielectrics that are used in MIM caps:
Silicon nitride: Si3N4 dielectric constant 7.5 (used in most MMIC MIM caps)
BTW, the dielectric constant of silicon nitride can vary depending on how it is deposited. Consult your favorite foundry!
Silicon dioxide: SiO2 dielectric constant 4.5
Titanium dioxide: dielectric constant 96
Materials for ceramic capacitors
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Barium titanate (very high but not stable...)
Ceramic capacitors formulas often use a mixture of barium titanate for high dielectric constant
Titanium pentoxide (Ti2O5): 41
Niobium pentoxide (Ni2O5): 26
Titanium oxide
Calcium titanate
Aluminum dioxide (Al2O5): 9.8
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