DTE Pedestal

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Direct Thermal Exchange Technology (DTE)

PCB Thermal Management Solution

As a solution to modern PCB thermal management issues, GSPK has created a, patent pending, novel Direct Thermal Exchange Technology.

PCBs are getting more powerful and as a result of denser packaging more complex thermal management challenges have to be addressed. There has never been a greater requirement to transfer heat away from components. Conduction via the circuit to a heatsink or cool plate is the usual way to do this.

The design and construction of the PCB and Thermal Conductivity of the materials used will affect how effectively these thermal problems are handled.

PCBs with ceramic substrates are becoming more popular as their thermal conductivity values are between 24 and 180 W/mK. This innovative technology is not appropriate for all applications due to production limitations including size and cost. Many people find that IMS (Insulated Metal Substrates) are a good solution. They were first developed to fight the growing junction temperatures of surface mount components on LEDs. They are composed of an aluminium/copper foundation and a thermally effective electrical isolating dielectric layer between the copper tracks and an aluminium/copper base. GSPK can offer multi-layer IMS boards. Thermal limits for aluminium IMS typically range from 8 to 10 W/mK.

IMS boards' thermal efficiency is increased even more by DTE - Direct Thermal Exchange Technology. The dielectric layer is a metal core IMS's primary thermal bottleneck, however with DTE, the dielectric layer is avoided by a plated, direct connection to the base layer. These connections are also know as Pedestals. This bypass allows for the heat to be delivered with reduced thermal resistance, controlling component temperature, extending component lifetime, and improving operational performance. Building pedestals is more dependable than thermal vias because of their greater copper mass and efficiency, which ensures that the heat is distributed more evenly and is transferred to the heatsink more effectively.

Up until this point, copper, which is heavy and expensive, served as the DTE base layer. GSPK provides DTE using a copper base, but we just created a patent-pending method that enables the plated copper connection to attach to an aluminium base, offering the conventional heatsinking materials of copper to aluminium. Using our technology, we can guarantee that the DTE (pedestal) will not split from the aluminium base and has successfully endured 1,000 thermal shock cycles.

Pedestal Technology Introduction

Compared to copper base DTE, aluminium base DTE offers the following four clear benefits:

Etching Method For Copper Base DTE Pedestals
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  • For DTE Pedestal technology, the "Etch Method" entails cutting the dielectric layer before bonding.
  • The pedestal is all that is left once the base copper is etched away.
  • The two layers can be bonded together.
  • This procedure must leave a minimum space of 0.1mm on either side of the pedestal feature in order to allow for registration tolerance between the machined dielectric and pedestal side.
  • The resulting void, particularly when combined with humidity and/or heat cycles, can expose the design to possible Hi-Pot test failures.
  • As opposed to DTE to an aluminium base, FR4 dielectrics must be used with a copper base.
Pedestal Technology Etch Method
Plating Method For Copper Base DTE Pedestals
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  • Starting with the bonded substrate, the "Plating Method" for pedestal technology exposes the metal base by first removing the dielectric to create the pedestal.
  • The pedestal is then created by directly plating up copper in these locations from the base.
  • Due to the longer processing time and greater plating cost, this procedure is more expensive.
  • However, the dielectric and copper register perfectly as a result.
  • This eliminates the possibility of the Hi-Pot test problems brought on by voids.
  • Depending on thermal concerns, a thick, heavy copper base may be required.
  • FR4 dielectrics need to be used with a copper base (not with aluminium DTE).
Pedestal Technology Plating Method
Plating Method For Aluminium Base DTE Pedestals
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  • Unique technique from GSPK; patent pending.
  • In contrast to copper, the bulk of IMS materials used for thermal management use an aluminium base.
  • GSPK has developed a method of plating a connection that is bonded to an aluminium base, making it possible to use aluminium DTE Pedestal technology where previously it was only possible to use Copper as the base.
  • 1000 thermal shock cycles were tested with this new technology.
  • A broad variety of exotic dielectrics are available as IMS uses aluminium for the base.
  • Aluminium finished panels are significantly lighter than those with solid copper bases.
  • Compared to solid copper, aluminium bases offer significant cost reductions as well.
  • Similar thermal performance to a copper base DTE board is provided by this technology.
  • Can also be used for current, a micro via for electrical contact - copper layer to aluminium which allows the base layer to be a ground layer.
Pedestal Technology Aluminium Base
Capabilities - DTE Pedestal Technology
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  Base Copper Weight (Thickness) Standard Special
Minimum Track Width 0.5oz (18um) 0.10 <0.10
1oz (35um) 0.10 <0.10
2oz (70um) 0.20 <0.20
3oz (105um) 0.25 <0.25
Minimum Track Gap 0.5oz (18um) 0.10 <0.10
1oz (35um) 0.15 <0.15
2oz (70um) 0.20 <0.20
3oz (105um) 0.25 <0.25
Hole Data Standard Special
Minimum Hole Size 1.20 N/A
Hole Tolerance - Drilled ±0.05 ±0.03
Hole Tolerance - Routed Holes ±0.10 +0 /-0.05
Minimum Hole to Edge 0.10 <0.10
Hole to Edge Tolerance ±0.15 ±0.10
Minimum Radial Clearance Pad (Annulus) 0.1 0.75
Min Pedestal SizeMin Pedestal Size
Max Pedestal SizeMax Pedestal Size
Pedestal GapPedestal Gap

Copper to Aluminium bond has passed the 1000 cycle test for thermal shock.

Number of Test Cycle (NCYCLE) 1000
Minimum Chamber Temperature (Tmin) -40°C
Maximum Chamber Temperature (Tmax) +125°C
Transfer Time (t2) between Chambers ≤10 S
Dwell Time (t) at low/high temp 15 minutes
Download Pedestal PCB Capabilities Document
Examples - DTE Pedestal Technology
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Copper Base

Pedestal Example 1
Pedestal Example 2
Pedestal Example 3
Pedestal Example 4

Aluminium Base

Pedestal Technology Aluminium Base
DFE Pedestal Example
DFE Pedestal Example 2

These pictures demonstrate GSPK's DTE technology, plating a copper pedestal through a dielectric to bond permanently to an aluminium base.

DFE Pedestal Example 3

Can also be used as a microvia for current, connecting copper to aluminium so that the base layer can operate as a ground layer.

The microsection pictured here was created following a 1000 cycle test for thermal shock.

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