CITIC Securities says thermal management for optical modules is shifting from a
supporting component to a performance-determining factor as 800G volumes scale
and 1.6T enters its initial volume year, raising per-module power and
temperature-precision requirements. Thermal solutions are evolving into a
three-tier stack: chip-level precise temperature control (Micro-TEC plus
ceramic-substrate heatsink), interface heat conduction (TIM gels and graphene
pads), and module-level heat spreading (VC spreaders/cold plates). Per-module
thermal content and pricing are rising with speed upgrades, and CPO/NPO
architectures that colocate optical engines and switching ASICs increase
same-domain cooling demand, supporting simultaneous volume and price growth
across the supply chain. Core components such as TECs and ceramic substrates
have been dominated by Japanese suppliers; domestic Chinese players are
accelerating breakthroughs, leaving substantial onshore substitution potential.
CITIC highlights three investment themes: TECs and ceramic substrates; TIMs and
graphene thermal materials; and VC spreaders plus liquid-cooling structural
parts.
