Digital selective growth of a ZnO nanowire array by large scale laser decomposition of zinc acetate

Abstract

We develop a digital direct writing method for ZnO NW micro-patterned growth on a large scale by selective laser decomposition of zinc acetate. For ZnO NW growth, by replacing the bulk heating with the scanning focused laser as a fully digital local heat source, zinc acetate crystallites can be selectively activated as a ZnO seed pattern to grow ZnO nanowires locally on a larger area. Together with the selective laser sintering process of metal nanoparticles, more than 10,000 UV sensors have been demonstrated on a 4 cm × 4 cm glass substrate to develop all-solution processible, all-laser mask-less digital fabrication of electronic devices including active layer and metal electrodes without any conventional vacuum deposition, photolithographic process, premade mask, high temperature and vacuum environment.

Laser Irradiation of Metal Oxide Films and Nanostructures: Applications and Advances

“…As an alternative to the complex and multistep conventional synthesis, growth, and patterning of MO nanostructures, laser‐induced direct selective growth of nanostructures has recently been proposed . Rapid, single‐step, and site‐specific growth of MO NWs directly on 3D structures using the laser‐induced hydrothermal growth (LIHG) method has been demonstrated . The simple and straightforward LIHG process typically involves irradiation of the target sample immersed in a precursor solution with a focused laser beam ( Figure a), which creates a confined temperature field inside the liquid.…”

“…g) Typical response of a UV sensor with and without ZnO NWs. c–g) Reproduced with permission . Copyright 2013, The Royal Society of Chemistry.…”

“…To extend the LIHG process to grow NWs on a large scale, initial laser patterning of ZnO NP seeds and subsequent NW growth by conventional hydrothermal synthesis were carried out (Figure c) . To demonstrate the feasibility of the above process to large‐area device fabrication, a UV sensor array was designed.…”

“…The large temperature gradients and high diffusion rates during laser processing lead to epitaxial growth rates that are orders of magnitude larger and effective heating times much shorter than that for conventional thermal treatment . Furthermore, the laser irradiation technique has been utilized for processing of complex nanostructures, such as site‐specific growth of nanowires (NWs) (e.g., ZnO, TiO 2 ) and nanorods (NRs) (e.g., Fe 2 O 3 , Ag/ZnO), spatial patterning of nanocrystals (e.g., ZnO) and NWs (e.g., Al 2 O 3 ), fabrication of nanosheets (e.g., Fe 2 O 3 ) and clustered nanostructures (e.g., Ag–ZnS@ZnO, Ag/WO 3− x ), production of oxide nanoparticles (NPs) by laser ablation in liquid (e.g., CuO, MnO x , Y 3 Fe 5 O 12 , Ag/TiO 2 , Y 2 O 3 :Eu 3+ , Gd 2 O 3 :Eu 3+ , Y 3 Al 5 O 12 :Ce 3+ (YAG:Ce), Fe@Fe 2 O 3 , or Fe 3 O 4 ), in situ formation of nanocomposites (e.g., Co 3 O 4 , MoO 2 , and Fe 3 O 4 particles embedded in graphene, ZnO particles embedded in poly(methyl methacrylate)), selective patterning of hybrid electrodes (e.g., Ni/NiO), direct scribing of fine structures (e.g., ITO), and direct writing of microdevices (e.g., TiO 2 , Cu/Cu 2 O).…”

Focused Energy Field Method for the Localized Synthesis and Direct Integration of 1D Nanomaterials on Microelectronic Devices

“…In terms of the local synthesis of nanomaterials, previously reported approaches based on the patterning of seeds or catalysts provide similar capabilities to those of the FEF synthesis method. However, because these methods realize local nanomaterial synthesis by seed/catalyst patterning through processes such as lithography, contact printing, inkjet printing or focused laser beam writing, they all require multiple steps such as alignment to the device electrodes, pattern definition, and surface cleaning. Furthermore, the chemical reactions for nanomaterial synthesis occur in the bulk phase and therefore waste a large amount of materials and energy.…”