Self-assembled, 3D nanoporous templates present an opportunity to develop devices which are lithography-free, massively scalable and hence, highly manufacturable. Self-limited deposition processes on the other hand, allow functional thin films to be deposited inside such templates with precision and unprecedented conformality. Taken together, the combination of both processes provides a powerful ‘toolbox’ to enable many modern nano devices.

In this work, I will present data in three parts. First, I will demonstrate the capabilities of Atomic Layer Deposition (ALD), a self-limited thin film deposition technique in preparing nanoalloyed Al-doped ZnO (AZO) thin films. These films are visibly transparent and electrically conducting. Structure-property relationships are established that highlight the power of ALD to tailor film compositions at the nanoscale.

Next, I will use ALD ZnO films in conjunction with aged, ALD V2O5 films to form pn junctions which show rectification with an I_on/I _off as high as 598. While, the ZnO is a well known n-type semiconductor, the discovery of p-type conductivity in aged V₂O₅ is surprising and is found to be due to the protonic (H⁺) conductivity of intercalated H₂O in V₂O₅. Thus, we demonstrate a mixed electronic-ionic pn junction for the first time.

Finally, I combine the material set of the pn junction with self-assembled, anodic aluminum oxide (AAO) 3D nanoporous templates to create 3D nanotubular pn junctions. The pn junctions are built inside pores which are only 90nm wide and up to 2&mgr;m deep and show rectification with I_on/I _off of 16.7.

Process development and integrations strategies will be discussed that allow for large scale manufacturing of such devices a real possibility.