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vlsi.chip - Chip Packaging -an Overview |
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Chip Packaging -an Overview The various types of IC Packaging are - Flip Chip
- Multichip Module (MCM)
- Chip Scale Package (CSP)
- Quad Flat Packs (QFP)
- Stacked Die Packages
- Ball Grid Array Packages (BGA)
- Land Grid Array (LGA)
- SiP
- Quad No-lead Packages (QFN)
- Plastic Leaded Chip Carriers (PLCC)
- SO
- SOT
- TSOP
- WLP
The metric to select the packaging are - Cost
- Reliability
- Form factor (Packing Density)
- Performance {Simultaneous Switching Noise, Signal Propagation, Power ground distribution}
- Thermal and Electrical Enhanced
In this article let us compare wire bond and flip chip package Wire bond 
- Flexibile
- Cost effective
- Suitable for�limited number of pads
- Mass production of wire-bonding pitch is in the range of 60 micron.
Challenges involved in Wirebonding - Reduction in Wire Diameter
- Wire length Increase
- Loop height minimum achievable
- Wire Bond pitch reduction
- Pad Size Opening reduction
- BGA Package total height reduction
Measures for Good Quality Wire-Bonding - Plasma clean prior to wire bonding
- Avoiding damaging to �Pad Metallization
- Using Wire Pull testing
- Meeting minimum bond strength limit
- Performing burn-in wire pull
Wire Bond Reliability Test - Performing Temperature cycle testing (TCT) for 1000 cycles from -65 to 150 degree C
- Wire pull test data exposed to 1000 hours at 150 degree C
- Intermettallic Mass(Halo) @ Ball edge
-Diagram Courtesy Atmel Flip chip - Good Power and Ground Distribution possible
- With the Area array more I/O density is possible
- Low stress over active area
- Targetted for High device speed
- Low inducatance effects
- Costlier
- Production area array pitch around 178 micron.
Process Flow's 
Future Technologies - WLP
- WLBI (Wafer Level Burn in)
- Optical Interconnects
- Multiple Die-Stacking
Companies Involved in IC Packaging - AmKor
- Signetics
- STATS ChipPAC
- ChipMOS
- Hana
- I2A
- Lingsen
- Infiniti
- OSE
- Shinko Electric
- SPEL
- UTAC
- Walton
- Carsem
- FlipChip� International
- Fujitsu
- Greatek Electronics
- Millennium Micro
- NS Electronics
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