Sökning: "2DEG"
Visar resultat 11 - 15 av 31 avhandlingar innehållade ordet 2DEG.
11. Semiconductor Nanoelectronic Devices Based on Ballistic and Quantum Effects
Sammanfattning : As current silicon-based microelectronic devices and circuits are approaching their fundamental limits, the research field of nanoelectronics is emerging worldwide. With this background, the present thesis focuses on semiconductor nanoelectronic devices based on ballistic and quantum effects. The main material studied was a modulation doped In0. LÄS MER
12. Electronic structure of clean and adsorbate-covered InAs surfaces
Sammanfattning : This thesis is the result of investigations regarding the processes in InAs III-V semiconductor surfaces induced by additional charge incorporated by adsorbates. The aim of the project is to study the development of the accumulation layer on the metal/InAs(111)A/B surfaces and its electronic structure. LÄS MER
13. Theoretical and optical investigations of some III-V based quantum wells and modulation doped heterostructures
Sammanfattning : This thesis is based on a combination of theoretical calculations and optical studies of the electronic structure and the radiative recombination processes in some III-V based quantum wells and ?-type modulation doped heterostructures. The optical studies includes photoluminescence (PL) spectroscopy, PL excitation (PLE) spectroscopy, and time-resolved PL. LÄS MER
14. Optimization of Ohmic Contacts and Surface Passivation for ‘Buffer-Free’ GaN HEMT Technologies
Sammanfattning : Gallium nitride high electron mobility transistors (GaN HEMTs) draw attention from high frequency and high power industries due to unique properties including high electron mobility and saturation velocity combined with high breakdown voltage. This makes GaN HEMTs suitable for power devices with high switching speed and high frequency applications with high power density requirements. LÄS MER
15. Quantum electronic transport in low-dimensional semiconductors
Sammanfattning : Electronic transport is studied at low temperatures in two-dimensional electron gases (2DEGs) and in mesoscopic semiconductor microstructures. The method of microwave-detection of the Shubnikov-de Haas effect for the contact-free characterisation of transport properties of 2DEGs is explored using both magnetic-field modulation and light-induced carrier modulation. LÄS MER