We all know that the heat of laser diode is very large, so do you know how to cool this product? Let's take a look at it together.

Common heat dissipation schemes (from weak to strong)

Passive heat dissipation+air cooling: a low-power device suitable for < ~ 2–5w thermal load (CW)

Forced air cooling (fan+large aluminum radiator): suitable for medium power, economical and practical.

Heat pipe/steam room+air cooling: suitable for medium and high power centralized heat source (several to ten W)

Water-cooled cold plate/microchannel cooling: suitable for high power or high integration density (tens of W or more)

TEC (temperature control)+heat dissipation: it is used for scenes that need accurate temperature control (laser frequency/wavelength sensitive), but the efficiency is poor, so it needs to cooperate with large heat dissipation capacity.

Direct Cu-based/CuW/AlN mount+metal welding: reducing the thermal resistance from junction to substrate, often used in industrial packaging.

Key materials and interfaces (in order of importance)

Chip-substrate contact: metallized flip chip or high thermal conductivity ceramics (AlN, Al₂O₃, CuW) are preferred as submount.

Solder/bonding method: Reflow or solderable metallization welding (such as AuSn, eutectic) or thermal conductive silver paste (used with caution, the thermal conductivity is lower than that of metal welding) is preferred.

Thermal interface materials (TIM): Thin, low thermal resistance phase change thermal pad, metal phase change, high performance thermal conductive silicone grease or metal solder paste.

Material of radiator: copper > aluminum (copper conducts heat well, but it is heavy); CuW/SiC is used for CTE matching and high power scenarios.

Package window/lens: Shi Ying for UVC/ deep purple, and glass for ordinary infrared; Note that the window material should also be heat-resistant and not yellowing.

The two models recommended above are how to dissipate the heat of high-power laser diodes. I hope you will be helpful after reading them.