摘要:

When ions pass through a crystal channel, they do not only feel a continuous potential of “atomic string”, but also an oscillatory electric field with a frequency equal to the ion velocity,v, divided by atomic spacing along the atomic string,d.Okorokov predicted that, if the electron of the ion has an excited state resonating with the frequency or one of its high harmonicsv= kv/d(k = 1, 2, …), it will be excited during the passage through the crystal channel and the ion emits a photon due to the deexcitation. The present author and coworkers observed first time the Kα X-rays from Ne9+and F8+ions channeled along the (111) and (110) axes of a gold crystal, respectively. In the present report, the possibility of the photon emission from the channeled heavy ions excited by the Okorokov effect is discussed and the experiments on the photon emission are surveyed.

ISSN:1042-0150    

DOI:10.1080/10420159308225497

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

A model for calculation of the range distribution of energetic ions with taking into account the channeling effect is proposed. The measurement of the depth distributions of boron ions in silicon crystals implanted at 13.6 and 91 MeV revealed significant difference between the measured and the calculated range profiles when the channeling effects have not been included in the calculation. In spite of deminishing the critical angles of channeling with growing ion energy the probability of the capture of ions into the channeling regime is significant in case of high energy implantation even when the incident angles are 7–10° off the main crystallographic directions.

ISSN:1042-0150    

DOI:10.1080/10420159308225498

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

The doping of silicon layers with low-energy (10–300) eV Ga+ions during growth by MBE has been studied. An increase in the coefficient of the gallium transport into the layer by 3–4 orders of magnitude has been observed as well as in the sharpness of the concentration profile in comparison with doping with neutral atoms.

ISSN:1042-0150    

DOI:10.1080/10420159308225499

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

The change in microstrains ϵ, block sizesLand in the temperature dependences of conductivity of polysilicon with the grain size 30-40nm at N+, Ne+, P+ion irradiation has been studied. It is shown that ϵ increases whileLpractically is not changing up to amorphization. The change in conductivity is governed by an increase in the density of states near the Fermi level and depends both on the damage rate for the given ions and their chemical activity.

ISSN:1042-0150    

DOI:10.1080/10420159308225500

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

Based on the previously suggested ideas on various possibilities of defect formation during particle bombardment and on monocrystal damage a general description of the laws of semiconductor amorphization process by particle irradiation was developed. It is based on the necessity of radiation structural defects accumulation in the quantities sufficient for a transformation of a single crystal into the amorphous state without using various amorphization mechanisms of the bombarding particles. In the case of low temperature bombardment (100 K) with various ions from helium to bismuth with displacement rates of 1.2-53 · 10−16part−1dpa · cm2it is sufficient to displace several percent of silicon atoms from their lattice sites. When the target temperature rises a damaging dose is necessary which provides more than a ten-fold displacement of each silicon atom. The determined shift of the amorphization dose temperature dependence curve towards higher temperatures with the increase of displacement rate data of the bombarding particles confirms the similarity of diffusion processes during the amorphization of semiconductors irradiated with any particles.

ISSN:1042-0150    

DOI:10.1080/10420159308225501

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

The dynamic mixing method, (or IVD one), which is one method of the coating film formation and has been developed by the present author and his collaborators, is introduced. The principle of this method is that the films are produced by vapor deposition and simultaneous bombardment of ions with energy 200eV-40keV and this method has various advantages, such as quick preparation of films, strong adhesion between film and substrate, preparation of thick films and that at low temperature.

ISSN:1042-0150    

DOI:10.1080/10420159308225502

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

We propose schemes of radiation defect formation in natural crystalline quartz, which explain different processes emerging in irradiated and electrolyzed samples and which cannot be interpreted within the frame of traditional models. The analysis of experimental results were carried out with reference to structural native and impurity defects and radiation centres.

ISSN:1042-0150    

DOI:10.1080/10420159308225503

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

The equilibrium solute atmosphere around a straight edge dislocation in interstitial solid solutions has been investigated. A long-range deformation interaction among impurities is accounted for. Quantitative estimations have been given for the example of carbonaceous martensite. The impurity concentrations in an atmosphere around the dislocation core are calculated for a given temperature in dependence on its mean value in the specimen. For a dislocation with an impurity atmosphere stationary fluxes of interstitial atoms and vacancies on the dislocation are calculated; a concentration dependence of impurity parameters indicating a dislocation capture efficiency of the self-interstitial atoms and vacancies and the parameter of dislocation preference B are received; a radiation-induced deformation rate (swelling and creep) is determined.

ISSN:1042-0150    

DOI:10.1080/10420159308225504

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

The thermal effect of the X-ray pulse on the X-ray optics basic elements is considered. A radiation intensity threshold is established over which the reflecting surfaces undergo destruction. For intensities below the threshold the surface temperature of various materials by the end of the X-ray pulse is calculated. The ways of reduction of the effect of heating a capillary and plane reflecting surfaces are analyzed.

ISSN:1042-0150    

DOI:10.1080/10420159308225505

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

The heating of various materials by X-ray pulses is studied. The relaxation of the excited electron subsystem of the material is investigated. A method for calculation of temperature distributions in the bulk of the material is developed and applied to different materials. The pulse length dependence has also been studied.

ISSN:1042-0150    

DOI:10.1080/10420159308225506

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor