Utilizing the “KRYSTAL^® Wafer”—a silicon substrate with a Pt/ZrO₂ buffer layer provided by I-PEX Piezo Solutions Inc.—we have successfully grown high-quality thin films of the strongly correlated oxide LaNiO₃ on a silicon substrate and demonstrated a technology that reversibly controls thermal conductivity through electrical manipulation. This study demonstrates that the superior epitaxial growth environment provided by the KRYSTAL^® Wafer enables the realization of advanced functionalities in LaNiO₃, opening up new technological possibilities for the development of thermal control devices.

 

Conventionally, sufficient performance for this type of functional material could only be achieved on expensive single-crystal substrates such as LSAT or YSZ, posing challenges in terms of cost and productivity for industrial applications.

In this study, by utilizing a Pt/ZrO₂ buffer layer, we successfully epitaxially grew LaNiO₃ on a standard Si substrate and experimentally confirmed that its crystallinity reaches a level comparable to that of single-crystal substrates. This signifies the achievement of high thermal switching performance that was not previously expected on Si substrates.

These results represent a significant step toward the development of devices requiring controlled thermal conductivity, particularly toward the realization of next-generation electronics equipped with thermal transistors and thermal management functions. In particular, the confirmation that high-performance thermal control materials can operate on Si substrates—the standard substrate in the semiconductor industry—is a major step forward toward practical application. This achievement holds significant business value from the perspectives of integration into manufacturing processes and mass producibility.