Fabrication Technology and Measurement of Coupled Quantum Dot Devices.
Abstract
This report describes the fabrication and measurement of planar tunneling devices. X-ray lithography was used to define gate patterns in order to achieve lateral electrostatic confinement in a two dimensional electron gas. Technologies were developed for the printing of features with linewidth of 50 nm and below, a lithographic resolution which is necessary for the fabrication of narrow tunneling barriers. Development of technologies such as this can also be used for large scale fabrication of silicon and GaAs devices and circuits with critical dimensions of 100 nm and below. Quantum dots in which the capacitances to the dot were minimized, were fabricated using high resolution lithography. Decreased capacitances to the dot increase the charging energy of a quantum dot, making it possible to observe single electron effects at elevated temperatures. The conductance of a device, featuring eight electrodes to control size and shape of a quantum dot, was measured in a Heliox insertion probe at a temperature of 300 mK. Measurements of several quantum dot sizes were performed and the results were discussed. The same device was biased to produce two unequal quantum dots in series. The results are discussed and compared with theoretical predictions.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 31, 1995
- Accession Number
- ADA294853
Entities
People
- Dimitri A Antoniadis
- Henry I. Smith
- Martin Burkhardt
Organizations
- Massachusetts Institute of Technology