Site-selective deposition and morphology control of UV- and visible-light-emitting ZnO crystals

Site-selective deposition of UV- and visible-light-emitting ZnO crystals was successfully achieved in an aqueous solution at low temperature. Molecular recognition was effectively utilized for patterning of ZnO crystals on self-assembled monolayers. Crystalline ZnO was further controlled to have different morphologies such as cylindrical hexagonal rods, ellipses, or multineedle shapes by changing the solution conditions to improve the photoluminescence properties. All of the morphologies emitted strong photoluminescence in UV and visible regions with different emission spectra. The novel process shows the high potential of solution processes for fabricating nano/microdevices constructed from crystalline materials for visible-light-emitting devices.