Решение задач управления при алмазно-искровом шлифовании сверхтвёрдых материалов

Представлено решение задачи управления, когда по требуемой чертежом шероховатости определяются различные сочетания режимов обработки, которые гарантируют получения необходимого качества поверхности. Результаты исследования проверены при обработке сверхтвёрдых материалов методом алмазно-искрового шлифования.Presented the solution to management tasks, when required by the drawing of roughness are determined by various combinations of processing modes, which guarantee obtaining the necessary surface quality. The study tested the processing of superhard materials by diamond–spark grinding

n-Type Doping of Vapor–Liquid–Solid Grown GaAs Nanowires

In this letter, n-type doping of GaAs nanowires grown by metal–organic vapor phase epitaxy in the vapor–liquid–solid growth mode on (111)B GaAs substrates is reported. A low growth temperature of 400°C is adjusted in order to exclude shell growth. The impact of doping precursors on the morphology of GaAs nanowires was investigated. Tetraethyl tin as doping precursor enables heavily n-type doped GaAs nanowires in a relatively small process window while no doping effect could be found for ditertiarybutylsilane. Electrical measurements carried out on single nanowires reveal an axially non-uniform doping profile. Within a number of wires from the same run, the donor concentrations ND of GaAs nanowires are found to vary from 7 × 1017 cm-3 to 2 × 1018 cm-3. The n-type conductivity is proven by the transfer characteristics of fabricated nanowire metal–insulator-semiconductor field-effect transistor devices

Library Links, vol. 10, no. 02 (December 1996)

The Health Sciences Library newsletter, published twice yearly from 1989-2006

<it>n</it>-Type Doping of Vapor&#8211;Liquid&#8211;Solid Grown GaAs Nanowires

<p>Abstract</p> <p>In this letter, <it>n</it>-type doping of GaAs nanowires grown by metal&#8211;organic vapor phase epitaxy in the vapor&#8211;liquid&#8211;solid growth mode on (111)B GaAs substrates is reported. A low growth temperature of 400&#176;C is adjusted in order to exclude shell growth. The impact of doping precursors on the morphology of GaAs nanowires was investigated. Tetraethyl tin as doping precursor enables heavily <it>n</it>-type doped GaAs nanowires in a relatively small process window while no doping effect could be found for ditertiarybutylsilane. Electrical measurements carried out on single nanowires reveal an axially non-uniform doping profile. Within a number of wires from the same run, the donor concentrations <it>N</it>_D of GaAs nanowires are found to vary from 7 &#215; 10¹⁷ cm^-3 to 2 &#215; 10¹⁸ cm^-3. The <it>n</it>-type conductivity is proven by the transfer characteristics of fabricated nanowire metal&#8211;insulator-semiconductor field-effect transistor devices.</p