Gold-plated cold plate

Overview
Joint program with Fraunhofer ILT (Germany) led to development of a new-structured microchannel heat sink that extends the service life of high-power LD modules. Complementary effects between Cu and Mo and precision internal channel fabrication produce low thermal resistance and a CTE matched to the LD mounting area. Au coating on channel interiors improves corrosion resistance.

Features
Realize higher power and longer life of the LD module

• Can accommodate 120 W-class LD
• CTE (coefficient of thermal expansion) controlled to approx. 8 ppm/°C
• LD can be mounted directly on the microchannel cooler without a submount (material dependent)

Realize longer life of the LD module

• CTE matching at the LD mounting area to reduce thermal stress
• Complete Au coating inside channels for corrosion prevention

Other feature points

• AuSn solder deposition on the LD mounting area
• Joint development with Fraunhofer ILT (Germany)

Options

• Material options: Cu-W-Cu or Cu (if Cu is selected, a submount is required)
• Diamond turning process available

Note: Patented in Japan, U.S. and EPC.

Fluid simulation
Fluid simulation illustrations and evaluation available to assess flow and cooling performance.

Evaluation features of standard specification
TC | Approx. 0.5°C/W | 500 ml/min
Flow rate | Approx. 500 ml/min | 150 kPa
Warpage | <1 μm | LD mounting area
Size | 11.0×20.0×1.55t (mm) | Single type
11.0×27.0×1.55t (mm) | Stack type

End user market / Applications
Industrial laser

• Laser equipment for welding, cutting, marking, surface treatment (e.g. annealing)
• Medical laser equipment for ophthalmology, epilation and endoscopic systems

Technical specifications

• Product name: Microchannel cooler
• CTE: 8 ppm/°C (CTE controlled by Cu-Mo-Cu 7-layer structure)
• Can accommodate: 120 W-class LD
• Thermal characteristic (TC): Approx. 0.5°C/W
• Flow rate (evaluation): Approx. 500 ml/min
• Operating/assessment pressure: 150 kPa (evaluation remark)
• Warpage: <1 μm (LD mounting area)
• Available sizes: 11.0×20.0×1.55t (mm) single type; 11.0×27.0×1.55t (mm) stack type
• Material options: Cu-W-Cu or Cu (if Cu, a submount is required)
• Surface/channel treatment: Complete Au coating inside channels for corrosion prevention
• Solder: AuSn solder deposition on LD mounting area
• Manufacturing option: Diamond turning process available
• Development partner: Joint development with Fraunhofer ILT (Germany)
• Intellectual property: Patented in Japan, U.S. and EPC