DIRECTED SELF-ASSEMBLY OF NANOSTRUCTURES FROM AMORPHOUS SEMICONDUCTORS

Professor Seebauer’s research focuses on surface and solid-state diffusion phenomena that govern semiconductor device fabrication at the nanoscale. Such fabrication requires techniques for the miniaturization and organization of materials at nanometer dimensions. Current techniques have developed from two diametrically opposite strategies. The “top-down” strategy carves device structures into semiconductor wafers using deposition, patterning, and etching. This strategy at the nanometer scale is exorbitantly costly. The “bottom-up” strategy synthesizes structures from smaller subunits through self-assembly. To date, this strategy has suffered grievously from high error rates.

During his Center appointment, Professor Seebauer will seek to demonstrate a new surface self-assembly method at the 10-100nm length scale using amorphous semiconducting materials. This new strategy combines attractive features of the top-down and bottom-up approaches by exploiting self-organization capabilities, latent in amorphous materials, in a way that can be controlled through exposure to optical or electron beam. The method should apply to a wide variety of semiconducting materials to form nanoscale particle arrays, pores, wires, and possibly three-dimensional structures. Potential applications include data-storage media; nanoparticle arrays for sensors and solar cells; and arrays for seed layers in the subsequent ordered deposition of sintered particle films. Such films find use in rechargeable batteries, solar cells, gas sensors, and photonic band gap materials for optical devices and solar windowpanes.