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MOVPE Growth and Characterization of Low-Dimensional III-V Semiconductor Structures

Carlsson, Niclas LU (1998)
Abstract (Swedish)
Popular Abstract in Swedish

Med hjälp av tekniker för att deponera enkristallina material i ytterst tunna skikt kan lågdimensionella strukturer i exempelvis halvledarmaterial åstadkommas. Karakteristiskt för lågdimensionella strukturer är att tjockleken hos enskilda skikt ligger i samma storleksordning som elektronernas de-Broglie våglängd. Som en följd av detta kan tydliga kvantmekaniska fenomen påvisas i lågdimensionella strukturer. I avhandlingen beskrivs egenskaperna hos lågdimensionella strukturer i valda III-V halvledarmaterial, tillverkade med metallorganisk gasfasepitaxi. Många III-V halvledare har, på grund av materialets elektroniska egenskaper, förmåga att utsända ljus vid exempelvis optisk excitation. Genom... (More)
Popular Abstract in Swedish

Med hjälp av tekniker för att deponera enkristallina material i ytterst tunna skikt kan lågdimensionella strukturer i exempelvis halvledarmaterial åstadkommas. Karakteristiskt för lågdimensionella strukturer är att tjockleken hos enskilda skikt ligger i samma storleksordning som elektronernas de-Broglie våglängd. Som en följd av detta kan tydliga kvantmekaniska fenomen påvisas i lågdimensionella strukturer. I avhandlingen beskrivs egenskaperna hos lågdimensionella strukturer i valda III-V halvledarmaterial, tillverkade med metallorganisk gasfasepitaxi. Många III-V halvledare har, på grund av materialets elektroniska egenskaper, förmåga att utsända ljus vid exempelvis optisk excitation. Genom fotoluminescens-spektroskopi kan därför kvantiseringsenergier i lågdimensionella strukturer bestämmas. I arbetet har också ingått att karakterisera ytstrukturer med hjälp av atomkraftsmikroskopi samt undersökningar av hur elektroner i lågdimensionella strukturer hos vissa typiska material uppför sig under påverkan av elektriska eller magnetiska fält. (Less)
Abstract
Metalorganic vapour phase epitaxy is used for growth of low-dimensional III-V semiconductor structures. The roughness of heterointerfaces in GaAs/GaInP quantum well structures is studied by photoluminescence emission from extremely narrow quantum wells. Results obtained for GaAs/GaInP quantum wells are compared to the more thoroughly investigated GaInAs/InP material combination. The potential of using a strain induced transition from a 2-dimensional layer-by-layer growth mode, towards 3-dimensional island growth, for generation of self-assembled quantum dots is demonstrated for the highly strained InP/GaInP and InAs/InP heterocombinations. Self-assembled dots of InP can also be formed on a GaAs substrate for a wide range of growth rates... (More)
Metalorganic vapour phase epitaxy is used for growth of low-dimensional III-V semiconductor structures. The roughness of heterointerfaces in GaAs/GaInP quantum well structures is studied by photoluminescence emission from extremely narrow quantum wells. Results obtained for GaAs/GaInP quantum wells are compared to the more thoroughly investigated GaInAs/InP material combination. The potential of using a strain induced transition from a 2-dimensional layer-by-layer growth mode, towards 3-dimensional island growth, for generation of self-assembled quantum dots is demonstrated for the highly strained InP/GaInP and InAs/InP heterocombinations. Self-assembled dots of InP can also be formed on a GaAs substrate for a wide range of growth rates and growth temperatures. Characterization by atomic force microscopy shows that the initial nucleation of self-assembled dots strongly depends on the growth rate and the growth temperature, resulting in a variable surface density of dots, as well as a variable dot size. Growth of modulation doped GaInAs/InP quantum wells at growth conditions previously optimized with respect to narrow line-widths in photoluminescence, results in an extremely high electron mobility, allowing detailed studies of the most prominent low-temperature scattering mechanisms. By etch-and-regrowth of a modulation doped GaInAs/InP quantum well structure, the formation of a quantum point contact is demonstrated. The quantum point contact exhibits a characteristic quantized conductance up to 10 K. After the initial optimization of the growth conditions with respect to photoluminescence properties of narrow GaAs/GaInP quantum wells, electron tunneling in GaAs/GaInP double-barrier resonant tunneling diodes is demonstrated. The active areas of the diodes can be scaled by the insertion of an array of embedded W discs in the upper GaAs cap layer. Vacant positions in the W disc array define the vertical current channel, while the areas without vacancies are semi-insulating due to an overlapping Schottky depletion from the W disc array. (Less)
Please use this url to cite or link to this publication:
author
opponent
  • Dr Scholz, Ferdinand, Universität Stuttgart
organization
publishing date
type
Thesis
publication status
published
subject
keywords
Semiconductory physics, low-dimensional structures, metalorganic vapour phase epitaxy, quantum wells, self-assembled dots, quantum dots, Fysicumarkivet A:1998:Carlsson, Halvledarfysik
pages
156 pages
publisher
Solid State Physics, Lund University
defense location
Lecture Hall B, Department of Physics
defense date
1998-05-08 10:15
external identifiers
  • Other:ISRN: LUFTD2/(TFFF-0050)/1-156
ISBN
91-628-2937-8
language
English
LU publication?
yes
id
28226f60-8cfa-4dd6-a21a-d0df3d18012b (old id 38663)
date added to LUP
2007-06-20 12:17:48
date last changed
2016-09-19 08:45:07
@misc{28226f60-8cfa-4dd6-a21a-d0df3d18012b,
  abstract     = {Metalorganic vapour phase epitaxy is used for growth of low-dimensional III-V semiconductor structures. The roughness of heterointerfaces in GaAs/GaInP quantum well structures is studied by photoluminescence emission from extremely narrow quantum wells. Results obtained for GaAs/GaInP quantum wells are compared to the more thoroughly investigated GaInAs/InP material combination. The potential of using a strain induced transition from a 2-dimensional layer-by-layer growth mode, towards 3-dimensional island growth, for generation of self-assembled quantum dots is demonstrated for the highly strained InP/GaInP and InAs/InP heterocombinations. Self-assembled dots of InP can also be formed on a GaAs substrate for a wide range of growth rates and growth temperatures. Characterization by atomic force microscopy shows that the initial nucleation of self-assembled dots strongly depends on the growth rate and the growth temperature, resulting in a variable surface density of dots, as well as a variable dot size. Growth of modulation doped GaInAs/InP quantum wells at growth conditions previously optimized with respect to narrow line-widths in photoluminescence, results in an extremely high electron mobility, allowing detailed studies of the most prominent low-temperature scattering mechanisms. By etch-and-regrowth of a modulation doped GaInAs/InP quantum well structure, the formation of a quantum point contact is demonstrated. The quantum point contact exhibits a characteristic quantized conductance up to 10 K. After the initial optimization of the growth conditions with respect to photoluminescence properties of narrow GaAs/GaInP quantum wells, electron tunneling in GaAs/GaInP double-barrier resonant tunneling diodes is demonstrated. The active areas of the diodes can be scaled by the insertion of an array of embedded W discs in the upper GaAs cap layer. Vacant positions in the W disc array define the vertical current channel, while the areas without vacancies are semi-insulating due to an overlapping Schottky depletion from the W disc array.},
  author       = {Carlsson, Niclas},
  isbn         = {91-628-2937-8},
  keyword      = {Semiconductory physics,low-dimensional structures,metalorganic vapour phase epitaxy,quantum wells,self-assembled dots,quantum dots,Fysicumarkivet A:1998:Carlsson,Halvledarfysik},
  language     = {eng},
  pages        = {156},
  publisher    = {ARRAY(0x7b5c770)},
  title        = {MOVPE Growth and Characterization of Low-Dimensional III-V Semiconductor Structures},
  year         = {1998},
}