Spintronic and plasmonic applications of electrodeposition on semiconductors

In this thesis, metal electrodeposition on semiconductor substrates is investigated. We show that electrodeposition of metals on n-type Si and Ge is an excellent method to create Schottky barriers and that this method has a number of unique advantages over other (physical) deposition methods. These advantages can be used to improve the prospects of applications in the area of Spintronics and Plasmonics.<br/>Firstly, the excellent current-voltage and capacitance-voltage characteristics of electrodeposited Schottky barriers indicate that they have an ideality factor close to unity and that the reverse bias leakage is orders of magnitude smaller than in evaporated Schottky barriers. These characteristics can be used to make highly doped Schottky barriers in which all reverse bias current is due to tunnelling. For magnetic metals, these Schottky barriers hence allow spin-conserved conduction which is a necessary step towards semiconductor spin valves and spin transistors.<br/>Secondly, electrodeposition is not a line-of-sight-technique and can hence be used to grow three dimensional structures when an appropriate pattern is created. Self assembly of latex spheres is shown to change both qualitative and quantitatively upon using a lithographically defined pattern. By using electrodeposition of gold around this latex sphere pattern nano-void array photonic crystals are created. We show that plasmonic modes are detectable in these arrays opening up the path to on-chip optical communication.

Name dc:type.qualificationname

Ph.D.

Level dc:type.qualificationlevel

doctoral

Grantor dc:publisher.institution

University of Southampton

Year dc:date.issued

2009

Author dc:creator

• Li, X.

Advisor dc:contributor.advisor

• de Groot, Cornelis H.