Title: AlSiC-Based Hybrid Composite Tool Kit
1"AlSiC-Based Hybrid Composite Tool Kit"
- By Richard W. Adams
- and Mark A. Occhionero
- Ceramics Process Systems
- 111 South Worcester St
- Chartley MA 02712-0338
- www.alsic.com
- New England IMAPS 31 Annual Symposium
- Thursday May 6, 2004
2"AlSiC-Based Hybrid Composite Tool Kit"
- Abstract AlSiC and multi-component structures
provide unique thermal management electronic
packaging solutions for microwave,
microelectronics, power electronics, and
optoelectronics that result in improved product
reliability. This paper reviews volume AlSiC
manufacturing applications today, and then
describes examples of a wide range of
possibilities for multi-component,
multi-functional thermal management structures.
3AlSiC Packaging for Electronics Thermal
Management- Basic Parameters
- Controlled Thermal Expansion
- Engineered CTE values - for component and
assembly compatibility reliability - Engineered solutions can create typical CTE
values 7-12 ppm/C - Thermal Dissipation
- High isotropic thermal conductivity, typical
200 W/mK - Lightweight
- 3 g/cm3
- Cost Effective Manufacturing Capability - net
shape cast
4CPS AlSiC Fabrication - Defines Properties and
Design
- SiC to Al-metal ratio defines thermal expansion
- 1st - SiC preform with controlled and variable
volume content - 2nd - Infiltrate with Al-metal to form the AlSiC
composite - Thermal conductivity determined by components
- Electronic Grade SiC 230 - 260 W/mK
- A356.2 Casting Alloy 160 W/mK
- Little influence of ratio of 2 components
- net shape forming
- preform is smaller than final part
- infiltration tool final dimensions
- eliminates costly machining
5AlSiC - Metal Matrix Composite Material
6AlSiC Tools
- Marry Properties to Product Design
- Design Functionality
- Basic AlSiC
- lids
- baseplates
- package system structures
- AlSiC Concurrent IntegrationTM
- Cooling Tubes - active fluid
- HOPG / Diamond - passive transfer
- Dielectric Ceramic Inserts - O isolation
7Basic AlSiC Design
See www.alsic.com
- Pick compatible AlSiC CTE
- Seal rings
- Substrates
- Devices
- Design rules for AlSiC casting
- Draft Angles
- Thicknesses
- Radii
- Al-Rich Areas for conventional machining
8Basic AlSiC - lids
- Simple to Complex Geometries
- Applications
- Microprocessor Lids
- DSP
- Flip Chip Lids
- Optical Lids
- Volumes
- 100 pcs - 40K/week
- Price (Volume/Complexity)
- 2 - 5 in volumes of 100K/yr
9Basic AlSiC - lids
- Product is net-shape fabricated - no machining
- multiple pedestals
- angled features
- radial alignment features
- septums and walls
- lower cost than machined Aluminum alternative
10Basic AlSiC - Baseplates
- Compatible CTE unlimited thermal cycling of
package - AlN soldered to AlSiC
- Design
- Dome Shape - Side 1
- Compressing a dome shape against flat cold plate
maximizes heat transfer - Flat - Side 2
- Attachment of flat substrates
Thomas Schuetze, Herman Berg, Oliver Schilling
The new 6.5kV IGBT module a reliable device for
medium voltage applications, PCIM September 2001
flat dielectric substrate surface
convex bow cooler plate surface
11Concurrent IntegrationTM -High Density
Interconnect (HDI) for GaAs Microwave
Transmit/Receive Packages
First, dense dielectric ceramic ferrules are
inserted into the QuickCastTM infiltration
tooling along with the SiC preform.
Then, the Al-metal, that infiltrates the SiC
preform to form the AlSiC composite, hermetically
bonds and fills the ferrules to form coaxial
feedthrus. This process is termed Concurrent
IntegrationTM.
12Concurrent IntegrationTM - AlSiC LED Submount
- Product Features
- multiple pedestals
- angled features
- partially machined to expose Alloy 49 pads for
assembly - Alloy 49 bonded direct to Al phase of AlSiC
Alloy 49 pad
13Concurrent IntegrationTM - Optoelectronic AlSiC
TE Cooler Substrate with HOPG
- High Thermal Conductivity Insert
- Product Features
- Pyrolytic Graphite (PG) compressively
encapsulated within AlSiC - Thermal conductivity 1300 W/mK
- PG located near heat source/TE cooler position.
- Selective use of costly material
Heat source surface
1350 W/mK
1350 W/mK
14Concurrent IntegrationTM - Liquid Flow Thru
Cooling
- Cooling Tube or Heat Exchanger
- Product Features
- Tube intimate within AlSiC casting
- SiC overmolded onto tube
- Direct bond AlSiC to tube
- Maximize heat transfer AlSiC to tube
- Low cost one step assembly
- CPS Patented process
15Metallurgical Bonding AlSiC to AlSiC
- Friction Stir Welding
- Bonding of Engineered Al-Rich Areas within AlSiC
casting - Al Solder Bonding Processes
- Various commercially available
- Desired Al Skin Present on AlSiC
Heat sink and housing are joined by Friction Stir
Welding.
16QuickCastTM High Pressure Precision Aluminum
Casting
- Aluminum-only precision casting
- Tolerances in the /-0.003 Range
- Low cost tooling
- Rapid product introduction and moderate
production rate - Option for Concurrent IntegrationTM
- Diamond, PG, etc inserts
- High Output LED light housing
- RV, Boats, Theater, Safety Lighting
17Summary "AlSiC-Based Hybrid Composite Tool Kit"
- Basic AlSiC Properties coupled with Concurrent
IntegrationTM - AlSiC Engineered CTE, Thermal Conductivity,
Lightweight - CPS AlSiC
- Shape Complexity and Tight Tolerance - net shape
- Attractive Value Proposition for many (growing
number) of Applications - Concurrent IntegrationTM Presents Thermal Package
Design Options - limited only to your imagination - AlN, ZTA, Al2O3, Si3N4 Substrates/Ferrules, etc.
- Stainless steel, alloy 49, Titanium inserts
- Tubes, Heat exchangers, welded pin fin coolers
- High Thermal Conductivity Diamond, PG
18Visit the CPS Booth