About reliability improvement of mixing AlAs/GaAs resonant tunneling diodes by design and engineering means
Engineering Education # 11, November 2013
In this article the authors propose an investigation method of changing current–voltage characteristic of a resonant tunneling diode influenced by degradation processes in its structure. An investigation of degradation of an AlAs/GaAs resonant tunneling diode structure at the temperature of 300°C was conducted. The findings show that in these conditions change in current–voltage characteristic of the resonant tunneling diode is mainly due to degradation of ohmic contacts. An analytic dependence of the resonant tunneling diode AuGeNi ohmic contact resistance on time and temperature was determined.
Study of diamond-like coatings by IR-spectral ellipsometry and Raman spectroscopy
Engineering Education # 07, July 2013
The authors conducted a study based on the use of such methods as IR-spectral ellipsometry and Raman spectroscopy of protective diamond-like coatings (DLC) which are applied on amide-imide resin samples. Within the framework of this investigation the ratio of sp2/sp3 bonds, optical constants, resistivity and thickness of protective diamond-like coatings were determined. The obtained data may appear useful when developing operating practices of coating DLC, as well as determining the relationship between physical and chemical characteristics of coatings (chemical composition, thickness, etc.) and their functional properties (barrier properties against negative space factors).
Study of nanostructured scintillator materials with synchrotron radiation source
Engineering Education # 12, December 2012
The authors consider aspects of studying time characteristics of scintillation detectors. They propose using synchrotron radiation to excite scintillation measurements to ensure the decay time of scintillation detectors with subnanosecond time resolution.
Study of thermal degradation of AuGeNi ohmic contacts of resonant tunneling diodes based on nanoscale AlAs / GaAs heterostructures
Engineering Education # 09, September 2012
The authors conducted a study of thermal degradation of AuGeNi RTD ohmic contacts. They propose an analytical dependence of contact resistance of AuGeNi RTD ohmic contacts on temperature and time (valid at temperatures ≤ 300 ° C). It can be used to predict reliability of RTD and electronic devices based on it in the given operating conditions.
77-30569/281952 Structural defect estimation of carbon fibers and polymer composites based on these fibers
Engineering Education # 11, November 2011
The results of structural survey of carbon fibers and epoxy micro carbon fiber composite were presented in this article. Attempt to determine damage mechanism of micro carbon fiber composite while in long operation was made, based upon the obtained results.
77-30569/282012 Raman spectroscopy of nanomodified polymer composite materials exposed to mechanical load
Engineering Education # 12, December 2011
In this article the authors present a research of physicochemical properties of constructional polymer composite materials (PCM) with addition of nanomodificatiors – astralene by method of Raman spectroscopy (RS). The authors conducted a research of polymer matrix chemical bonds with nanomodificators and parameters of packing characteristic of macromolecule. The authors made a conclusion of applicability of Raman spectroscopy method for estimation of on-stream PCM deformation degree when PCM are exposed to mechanical load.