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Laser-induced chemical deposition is an economical “grow-in-place” approach to produce functional materials. The lack of precise control over the component density and other properties hinders the development of the method towards an efficient nanomanufacturing technology. In this paper, we provide a mechanism of direct pulsed-laser integration of ZnO nanowire seeding and growth on silicon wafers toward controlled density. Investigation of laser-induced ZnO nucleation directly deposited on a substrate suggested that the coverage percentage of nucleus particles was a function of instantly available area, supplementing the classical nucleation theory for confined area deposition. A processing window was found in which ZnO nanowires only grew from the early deposited nucleated particles as seeds. A study on ZnO nanowire growth showed that the process became transport limited over time, which was important for density-controlled nanowire growth integrated on nucleated seeds. The proposed mechanism provided guidance to integrate nanomaterials using laser-induced chemical deposition with a controlled density and morphology. 

Monolithic strong magnetic induction at the mtesla to tesla level provides essential functionalities to physical, chemical, and medical systems. Current design options are constrained by existing capabilities in three-dimensional (3D) structure construction, current handling, and magnetic material integration. We report here geometric transformation of large-area and relatively thick (~100 to 250 nm) 2D nanomembranes into multiturn 3D air-core microtubes by a vapor-phase self-rolled-up membrane (S-RuM) nanotechnology, combined with postrolling integration of ferrofluid magnetic materials by capillary force. Hundreds of S-RuM power inductors on sapphire are designed and tested, with maximum operating frequency exceeding 500 MHz. An inductance of 1.24 μH at 10 kHz has been achieved for a single microtube inductor, with corresponding areal and volumetric inductance densities of 3 μH/mm 2 and 23 μH/mm 3 , respectively. The simulated intensity of the magnetic induction reaches tens of mtesla in fabricated devices at 10 MHz.