We used SSTR (Steady-State Thermal Reflectance) to measure the in-plane thermal conductivity of aluminum nitride (AlN) thin films. Our results demonstrated that these AlN films achieved record-setting thermal conductivities, surpassing even the heat-dissipating capabilities of diamond—one of the highest performing materials known for thermal conductivity.
The Challenge: Overcoming Thermal Conductivity Limitations in Thin Materials
High thermal conductivity materials show promise for thermal mitigation and heat removal in a variety of electronic devices. However, shrinking the length scales of these materials often leads to significant reductions in thermal conductivities, thus invalidating their applicability to functional devices.
Phonon−phonon scattering drives the in-plane thermal transport of these AlN thin films, leading to an increase in thermal conductivity as temperature decreases. This is the opposite of what is observed in traditional high thermal conductivity thin films, where boundaries and defects that arise from film growth cause a thermal conductivity reduction with decreasing temperature.
The Solution: Achieving High In-Plane Thermal Conductivity with SSTR Technology
Steady-state thermoreflectance can provide precise measurements of high in-plane thermal conductivities of 3.05, 3.75, and 6 μm thick aluminum nitride (AlN) film. At room temperature, the AlN films possess an in-plane thermal conductivity of ∼260 ± 40 W m−1 K−1, one of the highest reported to date for any thin film material of equivalent thickness. At low temperatures, the in-plane thermal conductivities of the AlN films surpass even those of diamond thin films.
Key Insights: Thermal Conductivity Measurements and Semiconductor Testing
This study provided valuable insight into the interplay among boundary, defect, and phonon−phonon scattering that drives the high in-plane thermal conductivity of the AlN thin films and demonstrates that these AlN films are promising materials for heat spreaders in electronic devices. This realization was enabled from SSTR measurements, which allow for unique sensitivities to in-plane thermal conductivity.
Key Benefits of Laser Thermal’s Thermal Conductivity Testing:
- In-Plane Thermal Conductivity Measurements with unprecedented precision
- Thermal Resistance vs Thermal Conductivity analysis for in-depth material insights
- Non-destructive testing using SSTR technology for accurate and reliable results
- Advanced Thermal Analytics for semiconductor testing and electronic devices
