Capacitor Selection Chart 
 
 
Capacitor (Dielectric) Type
Application
Aluminum Electrolytic
Energy storage (Power supply ripple reduction).  NOT suitable for timing applications or high-frequency supply bypassing. 
Solid Tantalum
Energy storage (Power supply ripple reduction).  NOT suitable for timing applications.
Tantalum Foil
Energy storage (Power supply ripple reduction).  NOT suitable for timing applications.
Ceramic
Power supply bypassing, coupling, timing (COG) and high voltage applications.
Teflon
Microwave applications
Polycarbonate
Timing and coupling
Polyester Film
Temperature stable, high voltage
Polystyrene
Timing, high precision
Polypropylene
Timing, Rp = 30 GOhm
Annular Band Glass
RF applications, high voltage
Embedded Band Glass
RF applications, high voltage, high capacitance
Silver Mica
RF applications, high voltage, Rp = 1 GOhm
Porcelain
Microwave applications
Quartz
High voltage, high Q
Sapphire
High dielectric constant, high Q
 

The above information is reprinted by permission from a lecture given by Larry W. Phelps.