Hybrid integrated circuits

1
Hybrid integrated circuits

• Thick film
• Thin film

2
Thick film (1)

• Suitable pastes are deposited via silkscreening
  (serigrafia) on a suitable substrate (usually
  ceramic, e.g. alumina) and then fired, in order
  to get
• - conductors
• - resistors
• - dielectrics, for capacitors
• Active components are then added

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Thick film (2)

• Paste components
• - binder (glass, which glues the functional
  element to the substrate)
• - vehicle (organic solvent)
• - functional element (metal, metal alloy, oxide,
  ceramics)
• Firing first a drying at 100 oC, then the actual
  firing at 500 1000 oC

4
Thick film (3)

• Characteristics
• - miniaturization
• - good for RF
• - low tolerances (via trimming)
• - power (good thermal conductivity of the
  substrate)
• - long term reliability/stability
• - low development and production costs

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Thick film (3)

• Example Sanyo STK4044
• 100 W audio amplifier
• THD 0.4 at 100W, 20 to 20kHz
• VCC /- 51V, Rload 8 W

6
Thin film (1)

• The same techniques used for monolithic ICs are
  used to deposit on a suitable substrate
  (ceramics, glass, quartz, alumina)
• - conductive (e.g. gold),
• - resistive (e.g. NiCr), or
• - dielectrics (e.g. SiO2) layers
• active components are then added
• in some cases, active components can be build
• using suitable layers

7
Thin film (2)

• Characteristics / applications
• - (obviously in monolithic ICs)
• - RF
• - miniaturization
• - high precision/stability resistors (wrt T)
• - long term stability/reliability
• - relatively easy production