Aluminum and copper Heat sink PCB

Aluminum and copper Heat sink PCB

To operate efficiently and ensure reliability, heat must be removed from heat generating power components.

As a result of faster speeds, reduced format, and more devices being populated on PCB’s, more heat is being generated that must be removed for efficient operation.

The move to sustainable-energy increased the demand for energy management electronics which also create much heat because of the high electrical currents as used on these applications (Power inverters for solar and wind-energy, powertrain electronics for HEV)

Thermal management through various applications aids in directing heat away from heat generating system components.

The following are a review of various thermal management approaches, applications and capabilities that can be supported.

Thermal Management Types Offered

Aluminum and copper Heat sink PCB

PCB Thermal Management –Pressure Sensitive Adhesive for Aluminum and copper

Pressure sensitive adhesive (PSA) is a lower cost option for attaching pallets / coins or plate-heatsinks to a PCB where electrical conductivity is not required.

Pressure Sensitive Adhesive advantages

  • Does not require a heat source for bonding, thus simplifying the bond process
    •  Bond to low surface energy substrates or surfaces
    •  Resists dielectric breakdown
    •  Relatively high Thermal resistance of tape
    •  Can meet aerospace and medical requirements
    •  Used in high volume in automotive applications (surface attached heatsinks).

 Old technology. Probably less demand in future as customers moving to alternatives.

Aluminum and copper Heat sink PCB

Aluminum-plate Heatsink Process Flow.

Process Flow:

Aluminum-plate Heatsink Process Flow

Raw material and production

3M Adhesive film

Al heat sink

Bare Board

Finished board

Main Process equipment used for ‘Aluminum-plate Heat-Sink’

PCBA Adhesive Tape roller pressing

1st laminating For PCB , Adhesive and Al plate

Final Hydraulic pressing

Copper Heat-Sink board

Copper Heat-Sink board

Copper Heatsink (heat-spreader).

On bottom-side the component-housing is soldered to GND-plane which contains thermal-Vias to conduct the heat to heat-sink.

Copper Heat-Sink board

Heat Sink Pick and Place machine is used to assemble copper heat-sink to PCB.

These copper heat-sinks are much thinner and smaller than the aluminum-plate heatsinks so suitable for Pick and Place process.

The automated process includes both ‘pick and place’ and ‘pressing’ of the copper heatsinks.

Copper Heat-Sink board

Main Process equipment used for the automated ‘Copper Heat-Sink’ process.

Pick and Place

Pressing

Screen printing

Customer test requirements for ‘copper Heatsink process’ includes

  • Voltage test (no electrical flash over at room temperature and 100V)
  • Solderability test (no delamination in the solder bath 288ºC/20sec.)
  • Adhesion test (the adhesive strength must be > 0.5N/mm)
  • Temperature cycle test (no delamination in 200 test cycles)

PCB Thermal Management – Heat Sink Paste

  • Heat Sink Paste (HSP) Thickness: 0.15mm
  • Position tolerance (e.g. HSP to PCB): /-0.2mm
  • Application by means of silkscreen printing process
  • Can be printed with the suitable geometry needed
  • Printing and curing in two steps (75um per step )
  • Final layer thickness 160 um
  • Excellent heat conductivity (2 W/mk)
  • High Isolation [ 30 KV/mm ]
  • Resistant against AFT/Isolation layer of Cu Structures against AFT

Heat Sink Paste (HSP) Examples

4L HSP PCB

4L HSP PCB

6L HSP PCB

Cerra Systems Boards Fabrication capabilities support high-frequency PCB, High-temperature Boards, Thick PCB, ultra-thin PCB, heavy copper PCB, Metal Core PCB, HDI boards with Blind Vias, Buried Vias, Micro Vias, Embedded passives, bonded heat sink, Impedance Control, Depth control drilling, Back drilling, Edge Plated PCB, Bump Pads, cavity with ledge, Via on pad and stacked micro-Via technology.

For more details on PCB manufacturing Capability ( HDI PCB , Rigid Flex PCBRF PCB ) visit us- http://cerrasystems.com/

Electronic Manufacturing Partners Profile includes:

Argus Systems (AESPL) – PCBPCBACable AssemblyBox BuildTesting..

EMSxchange – PCBACable AssemblyBox Build , TestingLogistics