Nanostructural characterization of amorphous diamondlike carbon films

Nanostructural characterization of amorphous diamondlike carbon (a-C) films grown on silicon using pulsed-laser deposition (PLD) is correlated to both growth energetic and film thickness. Raman spectroscopy and x-ray reflectivity probe both the topological nature of 3- and 4-fold coordinated carbon atom bonding and the topographical clustering of their distributions within a given film. In general, increasing the energetic of PLD growth results in films becoming more ``diamondlike'', i.e. increasing mass density and decreasing optical absorbance. However, these same properties decrease appreciably with thickness. The topology of carbon atom bonding is different for material near the substrate interface compared to material within the bulk portion of an a-C film. A simple model balancing the energy of residual stress and the free energies of resulting carbon topologies is proposed to provide an explanation of the evolution of topographical bonding clusters in a growing a-C film

GaN-Epitaxie, Prozesstechnologie und Aufbautechnik : Abschlussbericht ; Wachstumskern Berlin WideBaSe, Verbundprojekt 7: Hocheffiziente Leistungs-Mikrowellenverstärker und Oszillatoren, Teilprojekt 7.3: GaN-Epitaxie, Prozesstechnologie und Aufbautechnik ; Berichtslaufzeit: 01.07.2010 bis 31.12.2013

[no abstract available

Anwendungsgerechte Systemintegration und Zuverlaessigkeit fuer die intelligente mikromechanische Sensorik Abschlussbericht

A smart microsystem for reliable measurement of pressure with on-chip signal processing for linearity correction, temperature compensation and data storage of the individual adjustment parameters was developed. Programming is performed using a standardized interface. For the packaging of pressure microsensors thermo-mechanical mismatch of silicon to Pyrex is of serious concern, as it contributes to a temperature dependent output signal. For the minimisation of this effect, a new glass was developed, that fits better to silicon than Pyrex. For the manufacture of microsystem components by anisotropic etching of silicon on-line methods were developed that characterize the state of the etching solution. The quality of the etching process and the consumption of the etchant can be controlled by this method. For the precise manufacture of pressure sensor membranes a method for the optical in-situ control of the etch depth was implemented and tested. (orig.)SIGLEAvailable from TIB Hannover: F98B1066+a / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie, Bonn (Germany)DEGerman

Mechanism of Power Density Degradation due to Trapping Effects in AlGaN/GaN HEMTs

International audienc

AlGaN/GaN MIS-HEMT gate structure improvement using Al2O3 deposited by Plasma-Enhanced ALD

International audienceIn this work we evaluate the influence of the Al2O3 ALD deposition technique on AlGaN/GaN MIS-HEMT structures. It has been found that using O2 plasma as oxidizer instead of water could increase the threshold voltage considerably while greatly reducing gate leakage current. C(V) measurements have shown a very fast on/off transition even at 1kHz, with low frequency dispersion, while a record slope of 80mA/ decades was achieved between the on and off states through Id(Vg) measurements. Gate leakage currents were also drastically reduced with a measured average of 1e-11A/mm for a drain-source bias of 5V

Technologie- und Epitaxieentwicklung von AlGaN/GaN HFETs: Materialgüte, innovative Prozesstechnologie und Zuverlässigkeit : Schlussbericht

[no abstract available

Förderschwerpunkt: Wide Band Gap-Halbleiter, Teilvorhaben: GaN-Hochfrequenzelektronik : Abschlussbericht

[no abstract available