Sökning: "sapphire"

Visar resultat 21 - 25 av 65 avhandlingar innehållade ordet sapphire.

1. 21. Novel tantalate-niobate films for microwaves

   Författare :Jang-Yong Kim; Alex Grishin; Andrey B. Kozyrev; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; ferroelectrics; sodium potassium niobates; silver tantalate niobate; barium stronitium titanate; Electronics; Elektronik;

   Sammanfattning : Microwave materials have been widely used in a variety of applications ranging from communication devices to military satellite services, and the study of materials properties at microwave frequencies and the development of functional microwave materials have always been among the most active areas in solid-state physics, materials science, and electrical and electronic engineering. In recent years, the increasing requirements for the development of high speed, high frequency circuits and systems require complete understanding of the properties of materials function at microwave frequencies. LÄS MER

3. 22. Processing and On-Wafer Test of Ferroelectric Film Microwave Varactors

   Författare :Jang-Yong Kim; Alexander Grishin; Dag Winkler; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; : ferroelectrics; sodium potassium niobates; silver tantalite niobate; barium strontium titanate; thin films; pulsed laser deposition; rf magnetron sputtering; coplanar waveguide; photolithography; Electrical engineering; electronics and photonics; Elektroteknik; elektronik och fotonik;

   Sammanfattning : Microwave materials have been widely used in a variety of applications ranging from communication devices to military satellite services, and the study of materials properties at microwave frequencies and the development of functional microwave materials have always been among the most active areas in solid-state physics, materials science, electrical and electronic engineering. In recent years, the increasing requirements for the development of high speed, high frequency circuits and systems require complete understanding of the properties of materials function at microwave frequencies. LÄS MER

4. 23. Growth, characterization and processing of III-nitride semiconductors

   Författare :Fredrik Fälth; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

   Sammanfattning : The III-nitride semiconductor materials have wide direct bandgap ranging from 6.2 eV (AlN); through 3.4 eV (GaN) to 0.65 eV (InN). LÄS MER

5. 24. All-oxide ceramic matrix composites

   Författare :Marta-Lena Antti; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Materialteknik; Engineering Materials;

   Sammanfattning : This work has concerned the preparation and properties of all-oxide composites. The most common examples of such materials are composites of oxide particles in an oxide matrix, continuous oxide fibres in an oxide matrix and layered composites consisting of alternate layers of different oxides. LÄS MER

7. 25. Electronic materials : growth and characterisation

   Författare :Michael A. Grishin; Ulf O. Karlsson; Massimo Sancrotti; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electrophysics; Photoemission; Ultra-short laser pulse; Thin film; Laser deposition; InSb; InAs; GaSb; Ferroelectrics; Elektrofysik; Electrophysics; Elektrofysik;

   Sammanfattning : In this thesis the InSb(111), InAs(111) and GaSb(001) surfaces have been studied by means of time- and angle-resolved photoemission spectroscopy based upon the femtosecond laser system. The pump-and-probe technique allows to analyse both electron states in the valence band and normally unpopulated electron states above the valence band, which can be occupied by transiently excited carriers at the optically pumped surface. LÄS MER