Singh

Hinds

Rajaputra

University of Kentucky

Broadly speaking, two methods of fabricating nanomaterials are used. By lithographic means, structures with accurately controlled dimensions and material profiling can be built. This is the preferred method when performing electrical studies on nanostructures, but has the disadvantage of being expensive. On the other hand, methods capable of mass production have low cost but are not suited for building structures with precisely controlled features. The proposed method will be capable of mass producing nanoheterostructures, while still capable of controlling the physical dimensions of the structure to allow for meaningful theoretical studies on them and keeping the cost down.

The fabrication procedure would start with a glass substrate, on top of which a conductive material, the bottom electrode, is deposited. An Aluminum layer is then deposited and anodized leaving Aluminum stems, which through oxidation become Al2O3 insulating stacks. The voids are filled with layers of the desired materials, the main nano-heterostructure of interest. The top electrode is finally electrodeposited on top of them.

This deposition method offers the advantage that a large number of independent nano devices are built in a cost-effective manner in large scale. All these devices can easily be connected in parallel so that in solar cell applications, for example, the total generated power can be easily harnessed.

Each heterostructure can be independently characterized and studied. Even if no means of making individual contact to each cell is available, several cells can be connected using a relatively large contact (~100 nm). The whole system will still exhibit quantum confinement effects.