Miniature aerosol jet and aerosol jet array
View Patent ↗A miniaturized aerosol jet, or an array of miniaturized aerosol jets for direct printing of various aerosolized materials. In the most commonly used embodiment, an aerosol stream is focused and deposited onto a planar or non-planar target, forming a pattern that is thermally or photochemically processed to achieve physical, optical, and/or electrical properties near that of the corresponding bulk material. The apparatus uses an aerosol jet deposition head to form an annularly propagating jet composed of an outer sheath flow and an inner aerosol-laden carrier flow. Miniaturization of the deposition head facilitates the fabrication and operation of arrayed deposition heads, enabling construction and operation of arrays of aerosol jets capable of independent motion and deposition. Arrayed aerosol jets provide an increased deposition rate, arrayed deposition, and multi-material deposition.
1. An apparatus for depositing a material on a target, said apparatus comprising:
a plurality of channels for transporting an aerosol comprising the material;
a sheath gas chamber surrounding two or more of said channels;
a region proximate to an exit of each of said channels for combining the aerosol with sheath gas, thereby forming an annular jet for each channel, said annular jet comprising an outer sheath flow surrounding an inner aerosol flow; and
a plurality of separate extended nozzles extending from said region, one of said separate extended nozzles corresponding to each one of said channels and reducing the diameter of each said annular jet.
2. The apparatus of claim 1 wherein said plurality of channels form an array.
3. The apparatus of claim 1 wherein the aerosol enters each of said channels from a common chamber.
4. The apparatus of claim 1 wherein the aerosol is individually fed to at least one of said channels.
5. The apparatus of claim 4 wherein a second aerosolized material is fed to at least one of said channels.
6. The apparatus of claim 1 wherein an aerosol mass flow rate in at least one of said channels is individually controllable.
7. The apparatus of claim 1 comprising one or more actuators for translating or tilting one or more of said channels and extended nozzles relative to the target.
8. The apparatus of claim 1 further comprising an atomizer comprising:
a cylindrical chamber for holding the material;
a thin polymer film disposed on the bottom of said chamber;
an ultrasonic bath for receiving said chamber and directing ultrasonic energy up through said film;
a carrier tube for introducing carrier gas into said chamber; and
one or more pickup tubes for delivering the aerosol to said plurality of channels.
9. The apparatus of claim 8 further comprising a funnel attached to said tube for recycling large droplets of the material.
10. The apparatus of claim 8 wherein additional material is continuously provided to the atomizer to replace the material which is delivered to said plurality of channels.
11. The apparatus of claim 8 wherein said carrier tube comprises one or more openings.