Conventional nanosynthesis involves film growth followed by direct-write nanolithography. The last step has two major shortcomings in that (a) it causes material damage to the nanostructures and (b) it is always serial in nature whereby each wafer has to be patterned one at a time. The latter makes it impractical for large-scale commercial applications. To overcome these drawbacks, we have developed a novel and `gentle' electrochemical process for fabricating quantum dot arrays that allows parallel processing of millions of wafers. It causes minimal damage, is much cheaper than conventional nanolithography, and yet has the spatial resolution (approximately 1 nm) of state-of-the-art techniques. Semiconductor quantum dot arrays produced by this process show strong signatures of quantum confinement in their photoluminescence spectra. Superconducting quantum dots show a significant transition- temperature shift arising from an interplay of superconductivity with quantum confinement, while ferromagnetic quantum dots give rise to a novel giant magnetoresistance effect caused by remote spin-dependent scattering of electrons. These structures have also been characterized by a variety of analytical techniques--all of which attest to their high quality.

Date Published: 24 April 1995
PDF: 19 pages
Proc. SPIE 2397, Optoelectronic Integrated Circuit Materials, Physics, and Devices, (24 April 1995); doi: 10.1117/12.206875

Published in SPIE Proceedings Vol. 2397:
Optoelectronic Integrated Circuit Materials, Physics, and Devices
Manijeh Razeghi; Yoon-Soo Park; Gerald L. Witt, Editor(s)