Radiation hardening of metal-oxide semi-conductor (MOS) devices by boron

Technique using boron effectively protects metal-oxide semiconductor devices from ionizing radiation without using shielding materials. Boron is introduced into insulating gate oxide layer at semiconductor-insulator interface

Radiation hardening of MOS devices by boron

A technique is described for radiation hardening of MOS devices and specifically for stabilizing the gate threshold potential at room temperature of a radiation subjected MOS field-effect device with a semiconductor substrate, an insulating layer of oxide on the substrate, and a gate electrode disposed on the insulating layer. The boron is introduced within a layer of the oxide of about 100 A-300 A thickness immediately adjacent the semiconductor-insulator interface. The concentration of boron in the oxide layer is preferably maintained on the order of 10 to the 18th power atoms/cu cm. The technique serves to reduce and substantially annihilate radiation induced positive gate charge accumulations

Irradiation of MOS-FET devices to provide desired logic functions

Gamma, X-ray, electron, or other radiation is used to shift threshold potentials of MOS devices on logic circuits. Before irradiation MOS gates to be shifted are biased positive and other gates are grounded to substrate. Threshold lasts 10 years. Thermal annealing brings circuit back to original configuration

O razvoju metoda kompjuterske simulacije procesa oblikovanja metala

The comparative analysis of the main modern methods of the solution of metal forming boundary value problems is executed. The brief retrospective review of development of methods of the solution of metal forming boundary value problems (including methods of computer simulation) is made. The new method of computer simulation of metal forming processes. It is a method of linearization of nonlinear problems and is based on the variation of a finite element method. The outcomes of computer simulation of the upsetting process of stuffs with different flow characteristics is presented. The offered method and its modifications allow considerably to reduce time of the solution of boundary value problems, providing sufficient veracity of outcomes.Dana je usporedna analiza glavnih modernih metoda rješavanja problema graničnih vrijednosti oblikovanja metala. Napravljen je kratak retrospektivni očevid razvoja metoda rješavanja problema graničnih vrijednosti oblikovanja metala (uključujući metode kompjuterske simulacije). Nova metoda kompjuterske simulacije procesa oblikovanja metala je metoda linearizacije nelinearnih problema a zasniva se na varijaciji metode konačnih elemenata. Prikazani su rezultati kompjuterske simulacije postupaka savijanja materijala različitim karakteristikama protoka. Ponuđena metoda i njene modifikacije omogućuju značajno smanjenje vremena rješavanja problema graničnih vrijednosti, osiguravajući dovoljnu istinitost rezultata

Prodor slanih maziva u područje kontakta cijevi i trna u stanovima kontinuirane valjaonice cijevi

The mechnism of the salt phosphate lubricant ingress in zone of the tube deformation on a long cylindric mandrel was considered. Suggested mathematical model is based on the points of the hydrodynamic theory of lubrication. Data presented are concerned with a value of a salt lubricant layer thickness and friction factor between metal and mandrel at continuous hot rolling of tubes.Razmatran je mehanizam prodiranja soli fosfatnog maziva u zonu deformiranja cijevi valjanih na dugom cilindričnom trnu. Prijedlog matematičkog modela se osniva na hidrodinamičkoj teoriji podmazivanja. Podaci su prikazani vezano za vrijednosti debljine sloja podmazivanja i koeficijenta trenja između metala i trna pri toplom kontinuiranom valjanju cijevi

Application of the Prony method for biometric data analysis

The paper deals with the processing of numerical series using the spectral estimation methodology. The methodology is based on the Prony transformation. The conversion lets you represent the original number series as a new series. The new series is a linear combination of exponential functions. The article presents the basic concepts and relations of the Prony transformation, and also analyzes the behavior of individual components of the transformation for typical cases. The features of the Prony method are analyzed. Shown are the individual stages of the algorithm, the problems of a specific implementation. The Prony method was used to process the recordings of the electroencephalograms of the operators in their mental representation of movements. This allows us to assume the possibility of using the described methodology in identifying EEG correlates of motor imagination in the space of the roots of polynomials

Prediction and measurement of radiation damage to CMOS devices on board spacecraft

The CMOS Radiation Effects Measurement (CREM) experiment is presently being flown on the Explorer-55. The purpose of the experiment is to evaluate device performance in the actual space radiation environment and to correlate the respective measurements to on-the-ground laboratory irradiation results. The experiment contains an assembly of C-MOS and P-MOS devices shielded in front by flat slabs of aluminum and by a practically infinite shield in the back. Predictions of radiation damage to C-MOS devices are based on standard environment models and computational techniques. A comparison of the shifts in CMOS threshold potentials, that is, those measured in space to those obtained from the on-the-ground simulation experiment with Co-60, indicates that the measured space damage is smaller than predicted by about a factor of 2-3 for thin shields, but agrees well with predictions for thicker shields

Slope stability monitoring from microseismic field using polarization methodology

International audienceNumerical simulation of seismoacoustic emission (SAE) associated with fracturing in zones of shear stress concentration shows that SAE signals are polarized along the stress direction. The proposed polarization methodology for monitoring of slope stability makes use of three-component recording of the microseismic field on a slope in order to pick the signals of slope processes by filtering and polarization analysis. Slope activity is indicated by rather strong roughly horizontal polarization of the respective portion of the field in the direction of slope dip. The methodology was tested in microseismic observations on a landslide slope in the Northern Tien-Shan (Kyrgyzstan)