摘要:

Secondary ion mass spectrometric methods were used to study the effect of incident ion energy on atomic mixing in subsurface layers. A Ta2O5film containing a 50 A3lP-rich layer 230 A below the surface was depth profiled for phosphorus using normal incidence 160 primary particles of various energies (1.75 to 18.5 keV). A pronounced energy effect was observed in the widths of 31Pprofiles generated by >4 keV16O. For 18.5 keV16O, the observed profile contained two distinct components-the 31P-rich layer and the 31Precoil distribution. This later condition, prevails when the peak of the incident ion damage distribution occurs at a depth which equal or exceeds the distance from the surface to the 31P-rich layer. The desirable primary ion beam energy for characterizing the true elemental distribution is dictated by the shape and location of the layer to be profited. In most instances, a low energy beam is preferred.

ISSN:0033-7579    

DOI:10.1080/00337577408232406

出版商:Taylor & Francis Group    

年代:1974

数据来源: Taylor

摘要:

Making use of the general formula introduced by Ohtsuki, detailed calculations for diffusion coefficients in channeling are performed. The nuclear and single electron excitations are considered separately compared with the plasmon excitation. Some analytic expressions proposed in previous paper are confirmed.

ISSN:0033-7579    

DOI:10.1080/00337577408232407

出版商:Taylor & Francis Group    

年代:1974

数据来源: Taylor

摘要:

The effects of radiation on the formation of the agar-agar hydrogel were studied by measuring the penetration changes at different radiation doses and concentrations of added substances (sugar and potato starch). The behaviors of penetration against the radiation and the added substances were observed as follows. The experimental equations for the penetration changes were given by

ISSN:0033-7579    

DOI:10.1080/00337577408232408

出版商:Taylor & Francis Group    

年代:1974

数据来源: Taylor

摘要:

Low-temperature photoluminescence has been used to investigate the lattice damage created by boron ion implantation in Si. Silicon wafers were implanted with 120 keV B+ions to fluences of 1013and 1014ions/cm2at room temperature. Annealing effects and the flux dependence of the luminescence spectra are reported. In agreement with previous results for electron irradiation, luminescence peaks attributed to the divacancy and the Si-G15 (K) center are observed. In addition, zcro-phonon peaks which are not found in electron-irradiated Si are reported. These new peaks may be due to cluster defects containing boron.

ISSN:0033-7579    

DOI:10.1080/00337577408232409

出版商:Taylor & Francis Group    

年代:1974

数据来源: Taylor

摘要:

High-purity zone-refined molybdenum single crystals of the orientations (100),(110),(111) and (112) have been irradiated with electrons of 0.8-1.7 MeV energy at liquid helium temperatures. The lowest energy for atomic displacement was observed for the (100) specimen atEd= 850 ± 20 keV, which corresponds to a maximum transmitted energy ofTd(100)= 36 ± 1 cV. For the other crystals, the apparent thresholds varied betwecn 860 and 890 keV. Near Td, maximum damage rates were obtained for the (100) sample, followed by (110), (111) and (112); at T ≳ 2.5Td, the damage rates were iargest for (110), followed by (111),(100) and (112). Strong anisotropy effects were noted during annealing stage 1 as concerns thc four substages after low aiid high encrgy irradiation for the various orientations.

ISSN:0033-7579    

DOI:10.1080/00337577408232410

出版商:Taylor & Francis Group    

年代:1974

数据来源: Taylor

摘要:

Transmission electron microscnpe studies of Nb and Nb-1Zralloy irradiated to a fast neutron fluence of 2.5 × 1022n/cm2at 425°, 585°, and 790°C revealed the presence of voids in Nb at all three irradiation temperatures and unusually large voids in the Nb-1Zr irradiated at 790°C. No voids were observed in the Nb-1Zr irradiated at 425°C and 585°C. The voids in Nb irradiated a t 425°C and 585°C were completely annealed after one hour at 1230°C (∼0.55 Tm,) whereas complete annealing of the voids in Nb irradiated at 790°C occurred after one hour at 1380°C (∼ 0.60 Tm). The anneals at 1230°C and 1380°C for the Nb-1Zr alloy irradiated at 790°C served to increase tlie void size and decrease the void concentration. All evidence of the high concentration of small dislocation loops present in the Nb-lZr alloy irradiated at 425°C and 585°C was absent after annealing at 1230°C. Microhiardness measurements of both materials indicated that the significant radiation induced strengthening of Nb and Nb-1Zr at 425°C and 585°C was almost complctely recovered by annealing at 1230°C. Very little radiation-induced strengthening of both materials occurred at 790°C and was partially recovered during annealing at 1230°C. Annealing at 1380°C produced additional recovery for both materials at all irradiation temperatures. From an analysis of the results, it was concluded that vacancy trapping at oversize solute atoms was responsible for the suppression of void formation in the Nb-1Zr alloy during irradiation at 425°C and 585°C. However, the formation of voids in the Nb-121 alloy during irradiation at 790°C was concluded to be the result of simultaneous oxygen and/or nitrogen or carbon and vacancy migration. A reduction of the free vacancy concentration in the Nb-lZr alloy by vacancy trapping was found to enhance the void formation process at 790°C.

ISSN:0033-7579    

DOI:10.1080/00337577408232411

出版商:Taylor & Francis Group    

年代:1974

数据来源: Taylor

摘要:

Ion implantation of phosphorus into misaligned silicon crystals leads to a deep penetrating tail in the range distribution, due possibly to scattering into channels or to an anomalous diffusion process. Experiments have been carried out to test the various diffusion mechanisms so far proposed. It is shown that none of them accounts satisfactorily for the tail, which develops during the implantation process and is not thermally activated. A channelling mechanism is therefore favoured as the cause of the tail.

ISSN:0033-7579    

DOI:10.1080/00337577408232412

出版商:Taylor & Francis Group    

年代:1974

数据来源: Taylor

摘要:

An exact expression is presented for the total cross-section associated with the Winterbon, Sigmund and Sanders version of the Lindhard, Nielsen and Scharff differential cross-section for heavy ion-atom scattering. A series expansion form of the same quantity is also given.

ISSN:0033-7579    

DOI:10.1080/00337577408232413

出版商:Taylor & Francis Group    

年代:1974

数据来源: Taylor

摘要:

Several doses of 200 KeV phosphorus ions have been implanted under channeling conditions along the [110] direction in silicon.

ISSN:0033-7579    

DOI:10.1080/00337577408232414

出版商:Taylor & Francis Group    

年代:1974

数据来源: Taylor

摘要:

It is shown that diffusion of transversal energy due to discontinuity of atomic chains decreases exponentially, when the transversal energy decreases.

ISSN:0033-7579    

DOI:10.1080/00337577408232415

出版商:Taylor & Francis Group    

年代:1974

数据来源: Taylor