Reactive ion beam etching of InP with N2 and N2/O2 mixtures

A reactive ion beam etching process (RIBE) of InP with N2 and N2/O2 mixtures is described. The application of N2 of N2/O2 ion beams to InP results in high quality surfaces with virtual elimination of cone formation. The influence of the process parameters ion incidence angle, ion energy, ion beam current density, and N2/O2 ratio on etching rates is given for InP, Ni, Ti, Al, Si, and two types of photoresist (AZ4210, MP15). N2 RIBE has been used for the fabrication of grating structures with lambda =2400 AA periodicity. The gratings have been overgrown by liquid phase epitaxy without any degradation of the initial shape of the structure

Verfahren zur Herstellung eines Halbleiterbauelements mit durch reaktives Aetzen erzeugten Strukturen

DE 3344491 A UPAB: 19930925 In the prodn. of a semiconductor device based on III-V material with structures produced by reactive etching with accelerated ions. a gas mixt. consisting only of Ar and O2 is used as etching gas. Structurisation is carried out by reactive ion beam etching (RIBE). The selected angle of incidence of the ion beam to the surface of the solid to be etched is fixed by suitable inclination of the axis of rotation. The accelerated ions are neutralised electrically on their path to the solid to be etched. USE/ADVANTAGE - Etched surfaces with mirror quality and extremely small roughness can be produced with high selectivity and a high etching rate. The use of a corrosive halogen is avoided and the process waste gas is completely harmless. 0/

Future Cities- Analyse van het hitte-eilandeffect op Arnhem

Om vast te stellen of steden in Nederland ook hitte-eilanden zijn, is in augustus 2009, zowel in Arnhem als in Rotterdam, een temperatuurmeting uitgevoerd. Met een bakfiets vol meet apparatuur heeft Wageningen Universiteit op hete dagen in en om Arnhem en Rotterdam gefietst en is de temperatuur gemeten. Uit de voorlopige resultaten blijkt dat er sprake is van een temperatuurverschil van maximaal 7 °C tussen de temperatuur binnen en buiten de stad. Dit verschil is zowel in Arnhem als in Rotterdam aangetroffen. De omvang van de stad lijkt er niet toe te doen. Maar wat dan wel? Wat veroorzaakt nu het hitte-eilandeffect voor een stad als Arnhem

Clima urbano e saúde: uma revisão sistematizada da literatura recente

Foi feita revisão sistematizada de 67 artigos sobre o tema Clima Urbano e Saúde a partir de busca nas plataformas Web of Science e Pub Med. Os artigos foram organizados por data de publicação, país de realização do estudo, por temas: metodologias; evidências de riscos à saúde por estresse térmico e por doenças infecciosas relacionadas ao clima; mitigação dos extremos do clima urbano por vegetação e outras formas; cobenefícios e articulações políticas