Ultralow Contact Thermal Resistance between Bismuth Selenide Nanoribbons Achieved by Current-Induced Annealing

Thermal resistance at interfaces/contacts stands as a persistent and increasingly critical issue, which hinders ultimate scaling and the performance of electronic devices. Compared to the extensive research on contact electrical resistance, contact thermal resistance and its mitigation strategies have received relatively less attention. Here, we report on an effective, in situ, and energy-efficient approach for enhancing thermal transport through the contact between semiconducting nanoribbons. By applying microampere-level electrical currents to the contact between Bi₂Se₃ nanoribbons, we demonstrate that the contact thermal resistance between two nanoribbon segments is reduced dramatically by a factor of 4, rendering the total thermal resistance of two ribbon segments with a contact approximately the same as that of the corresponding single continuous nanoribbon of the same length. Analysis suggests that the ultralow contact thermal resistance is due to enhanced phonon transmission as a result of enhanced adhesion energy at the contact, with marginal contributions from direct electron-phonon coupling, even for ohmic contacts. Our work introduces a broadly applicable electrical treatment approach to various contacts between conducting and semiconducting materials, which has important implications for the design and operation of nanoelectronic devices and energy converters.