Heat management in thin films and coatings has always been an important consideration in applications including optics, tribological coatings, flexible substrates, and a broad range of electronic devices. The modern drive for smaller scaling and higher power or heat loads demands both technological innovations and a better understanding of heat transfer. Modern technology and materials are commonly progressing to sub-micron characteristic length scales. In this regime, classical laws of heat transfer no longer apply, and the energy of the individual energy carriers (electrons, phonons, and photons) and how they interact on the time and length scales associated with their scattering events must be considered (i.e., nanometers and picoseconds). This leads to phenomena such as reduced thermal conductivity of thin films compared to their bulk counterparts, thermal resistances of thin film heterosystems that are dominated by interfacial processes, and novel heat transfer processes that are driven by the coupling of energy carriers across interfaces of solids, liquids, gases and plasmas. In this full-day course, we will review the fundamentals of heat transfer from a nanoscale, or atomic perspective. From considering heat transfer properties of materials from this “bottom-up” perspective, we will overview the critical length and time scales that dictate changes in thermal conductivity of thin films that arise due to growth conditions, material processing, manufacturing, and heterogeneous integration. This course, which is designed for a technical community with little to no background in heat transfer, will cover the following topics:

Topical Outline:

• 1. What makes a high and low thermal conductivity material – an electron and phonon nanoscale perspective

• 2. Thermal conductivity measurements: thin film methods

• 3. Thermal conductivity of thin films: how film dimensional and growth conditions can lead to interfaces and defects that scatter electrons and phonons, thus reducing the thermal conductivity of materials

• 4. Thermal boundary resistance: coherent and incoherent heat transfer across interfaces in nanostructures

• 5. Coupled nonequilibrium heat transfer: Energy coupling among electron, phonons and photons including ultrafast laser pulse effects

• 6. Heat transfer in materials during synthesis and manufacturing, including plasma-material interactions during deposition and laser-based manufacturing