Solution‐Processed‐ZnO‐Mediated Semiconductor Bonding with High Mechanical Stability, Electrical Conductivity, Optical Transparency, and Roughness Tolerance

Abstract

Semiconductor bonding mediated by a transparent conductive oxide, ZnO, prepared by a simple solution spin-on process, is presented. The ZnO synthesis, sintering, and bonding processes are realized in a single step, thus providing a highly efficient semiconductor bonding method. The ZnO-mediated bonds simultaneously exhibit high mechanical stability, electrical conductivity, and optical transparency. The bonding's high tolerance for the roughness of the surfaces to be bonded is also demonstrated, due to the soft, deformable interfacial contact agent that is solidified in the bonding process, in contrast to direct bonding and bonding mediated by solid-state materials. Furthermore, the fabrication and operation of solar-cell devices are demonstrated using the developed ZnO-mediated bonding technique, with current paths across the bonded interfaces, thus verifying the practical applicability of the bonding scheme. The developed ZnO-mediated bonding scheme leads to low-cost, high-performance heterostructured optoelectronic device fabrication and integration.