In high-density AI servers, HPC compute modules, and autonomous driving domain controllers (Direct-to-Chip air/liquid chassis), high-power processors operate continuously at elevated temperatures (100°C–150°C).
Standard thermal pads pose critical long-term reliability risks under high operational heat:
Siloxane Volatilization: Unreacted cyclic siloxanes (D4–D10) vaporize and redeposit onto adjacent optical camera lenses and high-frequency electrical contacts, forming insulating films that induce signal loss.
Silicone Oil Bleeding: Excessive oil bleeding causes pad hardening and micro-cracking, driving non-linear TIM-2 thermal impedance climb.
Lixing Low-Volatile Thermal Conductive Pads solve these outgassing failure modes via molecular-chain entrapment and high-vacuum stripping.
Technical Core & Physical Mechanisms
1. High-Temperature Volatilization Kinetics & Langmuir Model
Mechanism: High-vacuum thermal stripping purifies residual siloxanes, while platinum addition networks entrain oligomers.
Plain-Text Langmuir Volatilization Equation: dm/dt = A * P_sat * (M / (2 * pi * R * T))^0.5 * (1 – C_locked) (dm/dt: Volatilization mass rate; A: Surface area; P_sat: Siloxane vapor pressure at temp T; M: Molar mass; R: Gas constant; T: Absolute temp; C_locked: Polymer matrix locking factor)
Engineering Benefit: Suppresses CVCM < 0.01% under 125°C continuous baking, preventing contamination of surrounding optical and electrical contacts.
2. Low Bleeding Rate & Long-Term TIM-2 Stability
Mechanism: Maintains filler-to-polymer matrix cohesion under continuous thermal aging.
Plain-Text TIM-2 Resistance Equation: R_contact = (d_pad / K_pad) + (Ra / (P_clamping * W_wetting)) (R_contact: Long-term total resistance; d_pad: Thickness; K_pad: Thermal conductivity; Ra: Surface roughness; P_clamping: Mounting pressure; W_wetting: High-temp wetting factor)
Engineering Benefit: Limits oil bleeding rate < 0.1%, preserving high-temperature wetting (W_wetting) and locking TIM-2 contact impedance over extended lifespans.
3. High Dielectric Strength & Low Stress Compliance
Low Mechanical Stress: Conforms easily to delicate dies at low assembly pressures, preventing mechanical stress damage while delivering high dielectric breakdown strength.
Industrial Applications
AI Server & HPC CPU/GPU Chassis Cooling: Mounted between processors and air heat sinks or direct-to-chip cold plates, delivering stable thermal transfer without outgassing contamination.
Automotive ADAS Domain Controllers & 5G Infrastructure: Withstanding harsh outdoor thermal cycling while protecting camera lenses and circuit contacts from volatile siloxane deposits.
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