New method for the Langmuir probe diagnostics of polymerizing plasmas

A pulsed Langmuir probe method of plasma diagnostics is proposed and validated for low-pressure, high-density, low-temperature plasmas capable of producing a nonconducting film on the probe surface. The method essentially involves cyclic probe-surface cleaning by ion bombardment. A switching pattern of probe potential is designed, taking into account the mechanism by which a space-charge region is formed near the probe. The method is successfully employed in an experiment on inductively coupled CHF₃ and Ar plasmas. The results of the experiment are presented.     

An investigation of spatial distribution of laser ablation products and their deposition on a substrate in the case of laser action with sharp focusing

Results are given of numerical simulation of the effect of laser radiation at a wavelength of 1.313 μm with sharp focusing on a silicon target. The behavior of the gasdynamic parameters is investigated, as well as the characteristic features of the modes of plasma formation, under such irradiation. The pattern is determined of the dependence of configuration and velocity of motion of the cloud boundary on the size of irradiation spot, angle of convergence of incident radiation, and its intensity. The time dependences are obtained for the temperature and density within the plasma cloud. The possibility of spraying the laser ablation products onto a substrate is assessed, and the configurations of deposited film are calculated for different modes of irradiation.     

Autonomous Path Estimation for a Descent Vehicle Using Recursive Gaussian Filters

This paper considers a refinement problem for the flight altitude, speed, and flight-path angle of an aircraft during aerodynamic deceleration in the atmosphere of Mars using inaccurate discrete g-load measurements. For solving this problem, several suboptimal discrete nonlinear filters of higher accuracy than the extended Kalman filter based on the Taylor linearization procedure with static (Gaussian) linearization of the nonlinearities are applied and compared with each other. The equations of these filters are derived, the Gaussian moments of their structural functions are calculated, and the resulting accuracy of these filters is analyzed in statistical terms.     

Crystallite-conjugation regions and adjacent lattice regions in polycrystalline iridium: III. Enthalpies of formation of vacancies and the energies of interaction of partners in vacancy complexes with oxygen formed in the cores of crystallite-conjugation regions in polycrystalline iridium

The interatomic spacings in the cores of crystallite-conjugation regions (CCRs) and adjacent lattice regions (ALRs) of polycrystals either decrease or increase upon alloying of nominally pure metals with oxygen and vacancy complexes with oxygen (mVacO, where m is the number of vacancies in the complex) that are formed during annealing. These changes in the interatomic spacings lead to an increase or decrease in the isomer shifts δ of the components of the Mössbauer spectra of atomic probes ⁵⁷Fe that are localized in the CCR cores and ALRs of polycrystals [1–6]. The enthalpies Q _mcmpl1, of formation of vacancy-oxygen complexes mVacO in the CCR cores have been measured for Ir and Cr polycrystals, and the enthalpies Q _Vac,1 of formation of vacancies in CCR cores have been determined for Ta, W, Ir, and Cr polycrystals. The enthalpies E _mcmpl of the interaction between the partners of the complexes increase with increasing number m of vacancies in the complexes.     

Analysis of the Effects Influencing the Retention Time of Filament-Based Memristors

Russian Microelectronics - A theoretical model that describes the degradation of the resistive states of the memristor over time has been proposing. It has been showing that the current through the...