Methods have been developed for the electro-deposition of single metals and multilayered combinations of metals into the pores of nano-porous polymer track etched membranes (nPTM). NPTMs with pore sizes in the range 30 - 100nm and above can be used and nanowires of different sizes and lengths made depending on the thickness of the membrane and the pore size. These nanowires can either be used in situ or extracted from the membrane by dissolving the polymer.
Single metals such as Co, Cu, Ni, Fe, Au, Ag etc and also alternating multilayered metallic nanowires of controlled layer thickness in the nanometer range for combinations of metals such as Ni/Cu, permalloy(NiFe)/Cu, Co/Ag, Co/Au, .Fe/Cu etc can be electro-deposited into the nanopores.
The single metal nanowires are useful for studying the magnetic properties such as switching whilst multilayered structures exhibit strong perpendicular GMR effects. Both of these effects will be useful in next generation sensitive magnetic sensor systems and possibly, also in the longer term, in data storage.
In addition, multilayered coatings covering larger areas can be deposited. Electro-deposition is potentially a much lower cost method than for example MBE whilst the nanowire geometry also offers advantages in terms of signal size and localization.
The end users of this result are likely to be companies making filled membranes, sensors producers and also people interested in multilayer deposition techniques in for example the electronics industry.