Accession Number : ADA301508

Title :   Research on Self-Assembling Quantum Dots.

Descriptive Note : Final rept. 10 Aug 94-31 Jul 95,

Corporate Author : CALIFORNIA UNIV SANTA BARBARA DEPT OF MATERIALS

Personal Author(s) : Petroff, P. M.

PDF Url : ADA301508

Report Date : 30 OCT 1995

Pagination or Media Count : 13

Abstract : We summarize the studies done under this contract by listing the main accomplishments in the last 6 years. We started this research by fabricating arrays of antidots in a modulation doped FET structure using a focused ion beam technology. The unique transport properties in these antidot arrays were also studied. We extended the focused ion beam technology to the fabrication of zero dimensional resonant tunneling diodes arid quantum wires fabricated using an insitu regrowth technique. We then switched the research to the growth and studies of self assembled nanostructures in the area of lateral superlattice growth and self assembling of quantum wire arrays, we have demonstrated MBE grown AiAs-GaAs lateral superlattice using transmission electron microscopy (TEM). We improved these self assembled lateral superlattices by growing the "serpentine superlattice" (SSL) using MIBE. The SSL produces directly an array of quantum wires over a large wafer area. Using TEM1 we were able to demonstrate AiAS-GaAs self assembled quantum wire arrays with adjustable dimensions. Optical studies of these self assembled quantum wires using polarized photoluminescence and photoluminescence excitation spectroscopy showed polarization effects that are associated with the ID character of the structure. A quantum wire laser using the SSL growth method was then fabricated. As expected from the 1 D character of the structure, the quantum wire lasers shows large gain an isotropy at temperatures up to 150 0K. in a second phase of this contract we turned our efforts to the fabrication and studies of self assembled quantum dots. We first demonstrated a method for producing InAs-GasAs self assembled quantum dots (SAD) using MBE. (AN)

Descriptors :   *SUPERLATTICES, *FIELD EFFECT TRANSISTORS, *QUANTUM ELECTRONICS, DIODES, POLARIZATION, CRYSTAL STRUCTURE, DEMONSTRATIONS, QUANTUM WELLS, GALLIUM ARSENIDES, PHOTOLUMINESCENCE, TUNNELING(ELECTRONICS), ARRAYS, GATES(CIRCUITS), FABRICATION, VOLTAGE, ION BEAMS, ELECTRON MICROSCOPY, QUANTUM EFFICIENCY, ALUMINUM ARSENIDES, WAFERS, ASSEMBLY, ELECTRICAL LOADS, MOLECULAR BEAM EPITAXY.

Subject Categories : Electrical and Electronic Equipment
      Quantum Theory and Relativity
      Crystallography

Distribution Statement : APPROVED FOR PUBLIC RELEASE