Localized Laser‐Based Photohydrothermal Synthesis of Functionalized Metal‐Oxides

We discuss the rapid in situ hydrothermal synthesis of metal oxide materials based on the photothermal superheating of light‐absorbing metal layers for simple and facile on‐demand placement of semiconductor materials with micrometer‐scale lateral resolution. Localized heating from pulsed and focused laser illumination enables ultrafast growth of metal oxide materials with high spatiotemporal precision in aqueous precursor solution. Among many possible electronic and optoelectronic applications, the proposed method can be used for laser‐based in situ real‐time soldering of separated metal structures and electrodes with functionalized semiconductor materials. Resistive electrical interconnections of metal strip lines as well as sensitive UV detection using photohydrothermally grown metal oxide bumps are experimentally demonstrated.