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5 Packaging Intro

•Ken Gilleo PhD•ET-Trends LLC

44%

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the

PackagePackage

DEVICEDEVICE JOIN

ING

JOIN

INGW

IRIN

GW

IRIN

G

PROTECTIONStandardization

PerformanceEnhancement

ThermalManagement

EasyTestability

AutomatedHandling

EasyAssembly

Enablerepair

Reworkability

PROTECTION

Chip to PCBCompatibility

Rerouting

Selective Accessto Environment

Enable MechanicalMovement

LowStress

MEMSMEMS

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Packaging Change Drivers

Packaging Change Drivers

1. Miniaturization Area Height Weight

2. Performance

High lead count

High frequency; processors, RF

3. MEMS/MOEMS/Nano; a new technology cluster

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DevicesDevices

TIME

PE

RF

OR

MA

NC

E

Solid State

MEMS

MOEMS

Nano

~50 Years

~50 Years

Vacuum

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• Base; platform; chip carrier

• 1st Level Interconnect (to chip)

• Routing (can be optional)

• 2nd Level Interconnect (to substrate/PCB)

• Enclosure; encapsulant

• Special features Thermal management Ports, windows, other

Basic Package Elements

Basic Package Elements

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Packages Element – cont.Packages Element – cont.• Substrate/Platform/Enclosure

Rigid organic; BT, etc. Flexible organic; polyimide Ceramic/glass Metal with insulation Protection; enclosure, encapsulation, passivation

• Chip Connections (1st level) Wire bond TAB Integrated TAB DCA; Flip Chip

• PCB Assembly (2nd level) Fusible: solder spheres/balls/bumps Non-fusible: leads, pins, pads

DIE

DIELECTRICSDIELECTRICS

CONDUCTORSCONDUCTORS

CONDUCTORSCONDUCTORS

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Lead FramesLead Frames• Metal – free standing or pre-inserted into dielectric

• Framing structure removed later

• Ceramic hermetic; used for MEMS

• Plastic Near-hermetic; limited use for MEMS

• Finishes for die attach/bonding Ag Pd Au Ni Multiple

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Chip CarriersChip CarriersChip Carrier: a packaging system for electronic chips (IC’s) that provides protection and a practical means of connecting to circuitry.

Fan Out: 2nd Level interconnect fans outward from 1st level

Fan In:

Conductor and Dielectric

First - 1964A flex-based package

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Area Array Packages

Area Array Packages

• Flip Chip

• LGA (Land Grid Array); leadless chip carrier, QFN

• PGA (Pin Grid Array)

• BGA (Ball Grid Array)

• Micro-BGA (CSP)

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Advanced Packaging Types

Advanced Packaging Types

• Advanced BGAs

• Flex-Based

• MultiChip

• CSP

• Array Molded

• Wafer-Level CSP and FC

PRODUCTIVITY

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Flip ChipFlip Chip

• Perimeter for small I/O count

• Area Array is much more effective

MEMS potentialSelective underfill

MEMS

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• Cofired

• Cast

• Molded

• Open (non-hermetic); chip carrier

Ceramic PackagesCeramic PackagesUsed for MEMS

Hermeticmoderately expensive

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Organic SubstrateOrganic Substrate• Rigid; mostly epoxies (resin-glass)

FR4 conventional

FR4 type non-halogenated

BT (Bismaleimide-triazine)

New non-epoxy halogen-free products

• Flexible

Polyimide

LCP

Limited use for MEMS

Non-hermeticLowest cost

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MultiChip PackagesMultiChip PackagesTraditional StackedSingle-Plane

Cavity type used MEMS + ASIC, other

Infineon MEMS mic + ASIC chip

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• Bond die (chip) to base; die attach)

• 1st Level connect chip; wire bonding

• Enclosure; encapsulant

Packaging StepsPackaging Steps

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Wire Bonding (WB)Wire Bonding (WB)• Most common connection

• Gold ball bonding dominants (~ 93%)

• Features Programmable; handles die and package change Very versatile Universal method Fast, automatic, equipment makers keeping pace Fully mechanical process Clean; no pollution, waste, hazardous materials Well-suited for MEMS/MOEMS

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Package ProtectionPackage Protection

• Fabricated cavity enclosure; metal, plastic, ceramic

• Transfer Molding Compounds (solids)

• Glob Top; free flow encapsulant

• Dam & Fill encapsulants

• Cavity fill encapsulants

• Underfill; 4 basic classes

• Underfill + encapsulant

• Injection molded cavity packages; near-hermetic

DIE

Most can’t be

used for MEMS

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BGABGA

DIE

encapsulants: for protection & handling

Only suitable for capped MEMS

CAP

MEMS

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Session SummarySession Summary• Packaging is very dynamic today

• The package is all about metal & dielectrics

• Challenges are greater than ever

• Chip advances push performance

• WLP is finally gathering momentum

• MEMS is opening up a new packaging industry