The heat dissipation copper plate of the optical module is the core component of the thermal management of the high-speed optical module. With the iteration of 800G to 1.6T and 3.2T, the power consumption of the module has skyrocketed from 15W to 45W, and the local heat flux density of the DSP chip has exceeded 100W/cm ². The thermal conductivity of the traditional zinc alloy and aluminum alloy shell has reached the physical limit, and the high thermal conductivity copper plate has become a rigid demand solution to break through the heat dissipation bottleneck.
Core application scenarios and values
High-power optical module body heat dissipation: instead of the traditional zinc alloy shell, using MIM or 3D printing process to form a pure copper heat dissipation shell, the thermal conductivity can reach 390~ 401 W/m · K, which is 2~ 3 times that of zinc alloy. The chip junction temperature can be directly reduced by 5~ 10 ° C, greatly reducing the laser wavelength drift, DSP thermal protection and other failures. At present, the MIM copper alloy optical module shell of Jingyan Technology and other manufacturers has entered the trial production verification stage of top-tier clients, and the penetration rate is rapidly increasing.
DSP chip exclusive thermal expansion base: On the back of the DSP chip of the 800G/1.6T optical module, the high-precision copper plate (or tungsten-copper composite copper plate) is directly welded as a low thermal resistance "heat dissipation high-speed channel", which quickly spreads the concentrated heat of the chip to the shell and avoids the signal error bit rate caused by local hot spots. It is the standard configuration in the current 1.6T optical module mass production plan.
Liquid-cooled light module micro-channel cold plate: Through the MIM process, the internal closed micro-channel copper plate is integrally formed to eliminate the hidden danger of weld leakage in the traditional welding process. There is no flux residue inside the flow channel, and the cleanliness is higher. It is suitable for data center immersion liquid cooling and rack-type cold plate liquid cooling scenarios, which can increase the power density of the cabinet from 15kW to 45kW. At present, this type of product has been shipped in batches in energy storage and edge computing server scenarios.
TEC semiconductor refrigeration integrated copper plate: embedded in the optical module TEC refrigeration assembly, optimize the thermal conductivity connection structure between thermoelectric units, greatly improve the heat exchange efficiency of TEC, and reduce the power consumption of TEC itself while ensuring the accuracy of laser temperature control. Liante Technology and other manufacturers have achieved mass production through relevant patents.
Industry landing progress
The current optical module cooling copper plate is in the key stage of switching from the traditional solution to the high-performance copper-based solution: the 1.6T OSFP package module has generally used the copper plate as a standard heat dissipation base, and the copper alloy cold plate with an independent floating structure developed by the head manufacturer can be perfectly adapted to the hot-swappable scene of the optical module, which not only ensures close fit with the module shell to balance heat conduction, but also avoids the problem of insertion stuck. The penetration rate of copper-based heat dissipation components in high-speed optical modules will usher in a rapid increase in the next 2 to 3 years.
