MBE, molecular beam epitaxy, is a way to control crystal growth to the nano level. It allows for the growth of designer crystals, within fairly strict limits, in two dimensions. Combined with e-beam defined lithography, high resolution etching methods and regrowth techniques, a limited amount of 3D control is possible.
Nanotechnology is a field of endeavor encompassing any methods for making or applications for using nanometer sized devices.
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