A prototype was developed in Phase I for measuring the thermal conductivity of thin films, proving the capabilities of a measuring technique in the range not covered by any other existing commercial equipment. The measurement method is based on the definition of the thermal resistance, as opposed to the mostly indirect methods used in the past. Its operating range extends from thin optical films to bulk materials. The technique was verified by measurements of thin and thick bulk samples and the results closely correlate with the published values for those materials. Final testing was accomplished by successfully measuring two micrometer thick SiO2 films deposited on single crystal silicon substrates. During Phase II the performance of the system will be significantly improved, leading to a useful commercial instrument. Modifications are planned for the sensor head, electronic circuit and control software. Development and commercial availability of a nondestructive test for thermal conductivity and interface thermal resistance in dielectric and other thin films will permit rapid advances to be made in the design and construction of multilayer structures with improved heat flow characteristics. Several technologies will be aided by this instrument, with applications in high speed electronics, optics, optical and magneto-optical recording, thin films, superconducting films, as well as diamond-like coatings.
