摘要:

A systematic study on the nature and evolution of the postannealing defects in BF+2‐implanted silicon with implantation doses ranging from 5×1014to 1×1016cm−2is reported. The type, nature, size, distribution, and density of the defects were determined by transmission electron microscopy. Formation mechanisms of the microstructural defects are discussed.

ISSN:0021-8979    

DOI:10.1063/1.335852

出版商:AIP    

年代:1985

数据来源: AIP

摘要:

A method has been developed to calculate the depth distribution of recoil atoms that result from ion implantation onto a substrate covered with a thin surface layer. The calculation includes first order recoils considering projected range straggles, and lateral straggles of recoils but neglecting lateral straggles of projectiles. Projectile range distributions at intermediate energies in the surface layer are deduced from look‐up tables of known range statistics. A great saving of computing time and human effort is thus attained in comparison with existing procedures. The method is used to calculate recoil profiles of oxygen from implantation of arsenic through SiO2and of nitrogen from implantation of phosphorus through Si3N4films on silicon. The calculated recoil profiles are in good agreement with results obtained by other investigators using the Boltzmann transport equation and they also compare very well with available experimental results in the literature. The deviation between calculated and experimental results is discussed in relation to lateral straggles. From this discussion, a range of surface layer thickness for which the method applies is recommended.

ISSN:0021-8979    

DOI:10.1063/1.335853

出版商:AIP    

年代:1985

数据来源: AIP

摘要:

Computer codes for synthesizing random and channeling backscattering spectra have been elaborated to characterize the surface and interface structures formed or modified by ion implantation. Both effects of isotopes and energy fluctuation are taken into account in the spectrum simulation. This backscattering measurement combined with the simulation method is applied to characterization of the N+‐implanted Al films and to quantitative analysis of chemical reaction and interdiffusion induced by ion‐beam mixing. An ion‐beam‐induced damage profile and its epitaxial recovery of crystallinity are analyzed by the simulation of channeling spectra from ion‐implanted Al2O3substrates.

ISSN:0021-8979    

DOI:10.1063/1.335854

出版商:AIP    

年代:1985

数据来源: AIP

摘要:

Although both the Cu/W and Cu/Ta alloy systems are known to be immiscible, the response of coevaporated amorphous films ofa‐CuxW1−x(x=0.45–0.72) anda‐CuxTa1−x(x=0.10–0.55) alloys to thermal annealing and ion irradiation is very different. Alloys ofa‐CuxTa1−xcrystallize between 600 and 800 °C, with the crystallization temperature increasing with Ta concentration, whilea‐CuxW1−xalloys crystallize below 200 °C. Likewise in Xe‐ and Ne‐ion irradiation studies,a‐Cu/Ta can still be observed after ∼13 displacements per atom (DPA), whereasa‐Cu/W alloys completely transform to solid solutions after ∼0.08 DPA. The results of this study, in combination with previous investigations of amorphous alloys of immiscible systems, show that the crystallization temperatureTcis not predicted equally well for systems with a positive or negative heat of formation. It appears that the kinetic model of crystallization only applies if the transformation proceeds through long‐range diffusion. Amorphous alloys which have a positive heat of mixing are predicted to undergo a polymorphic transformation at lower temperatures.

ISSN:0021-8979    

DOI:10.1063/1.335855

出版商:AIP    

年代:1985

数据来源: AIP

摘要:

Hall data on vapor‐phase‐epitaxial InP doped with Si, S, Sn, and Se and liquid‐encapsulated‐Czochralski InP doped with Ge are presented for doping levels between 1015and 1019cm−3. The results show nearly identical electrical behavior for alln‐type dopants but a consistent discrepancy with theoretical mobility calculations, particularly in the doping range 1017–1019cm−3. A chemical analysis of the sulphur content in layers doped with sulphur shows that all the dopant is electrically active. The reason for the discrepancy with the calculation is discussed in terms of the description of ionized impurity scattering in the presence of a high density of ionized centers. We also emphasize the similarity with GaAs and suggest that our conclusions apply equally to both materials.

ISSN:0021-8979    

DOI:10.1063/1.335831

出版商:AIP    

年代:1985

数据来源: AIP

摘要:

The electronic properties of the defectE4generated in GaP by 1‐MeV electron irradiation have been studied. The defect exhibits very strong athermal annealing effects undere‐hrecombination conditions. By comparing thermal and optical data evidence is obtained for lattice relaxation when the charge state of theE4defect is changed. A simple configuration coordinate diagram is presented which is in agreement with experimental data and which explains several important features of recombination‐enhanced defects reactions and athermal annealing phenomena.

ISSN:0021-8979    

DOI:10.1063/1.335832

出版商:AIP    

年代:1985

数据来源: AIP

摘要:

We present an analytical model for the calibration of lateral piezoresistance stress gauges in shock‐wave experiments. This calibration is based on our experimental data with transverse Manganin gauges in shock‐loaded polymethylmethacrylate targets. The experiments included lateral stress measurements under shock loading in the 1–30‐kbar range and under complete unloading from stresses in the 5–9‐kbar range. These unloading measurements resulted in a negative resistance change for the transverse Manganin gauge which implies that a hydrodynamic tension exists in it. The validity of our analytical calibration is demonstrated by comparing measured and predicted lateral stresses in glass targets.

ISSN:0021-8979    

DOI:10.1063/1.335833

出版商:AIP    

年代:1985

数据来源: AIP

摘要:

Plate impact experiments were performed on commercial alumina disks (AD‐85, manufactured by Coors), with in‐material Manganin gauges, in order to determine the dynamic response of this material in the 0–100 kb range. The measured stress signals showed that the transmitted waves, at the high stress range, are composed of an initial elastic jump, to about 60 kb, followed by a dispersive rise to the final stress level. This behavior was found recently for pure alumina but not for AD‐85. We used the gauges to determine the Hugoniot curve of AD‐85 in the 0–100 kb range and its spall strength in this region.

ISSN:0021-8979    

DOI:10.1063/1.335807

出版商:AIP    

年代:1985

数据来源: AIP

摘要:

Lateral diffusion of In in 20–100‐nm‐thick Au‐In films has been studied in the 60–150 °C temperature range. Indium diffusion due to the chemical potential gradient occurs from In to Au‐In with an AuIn2phase being formed in the diffusion zone. The growth of the diffusion zone obeys a parabolic rate law with the growth rate strongly dependent on In concentration of the films. In order to understand these phenomena, the kinetics of the AuIn2phase formation is analyzed considering In diffusion due to the chemical potential gradient with subsequent formation of AuIn2at the diffusion front. As a result of this analysis, the diffusion coefficient of In in AuIn2films is obtained asDIn=1.2×10−3 exp(−0.52 eV/kT) cm2/s. Grain boundary diffusion is thought to be the dominant mechanism. Additionally, a combined diffusion parameter &dgr;Dg(&dgr; is the grain boundary width) of 1.3×10−16cm3/s (60 °C) is obtained.

ISSN:0021-8979    

DOI:10.1063/1.335808

出版商:AIP    

年代:1985

数据来源: AIP

摘要:

The moving species during the formation of Pt2Si, Ni2Si, and CrSi2by both ion mixing with 300–600 keV Xe ions and thermal annealing is identified with inert markers using backscattering spectrometry. Samples of metal‐on‐silicon and silicon‐on‐metal have been used, evaporated on SiO2substrates with two very thin markers (Mo for Pt2Si, W for Ni2Si and CrSi2) placed at the metal–silicon interface, and at the bottom interface with the SiO2substrate. Monitoring the separation of the two markers as a function of the amount of silicide formed determines the ratio of atomic transport through the growing silicide layer. The results establish that the dominant moving species in both silicide formation processes is the same for the refractory metal‐silicide CrSi2, e.g., Si, whereas different atomic transport ratios are found in the case of the near‐noble metal silicides Pt2Si and Ni2Si. This outcome is discussed in terms of high‐temperature effects during thermal formation of transition‐metal silicides.

ISSN:0021-8979    

DOI:10.1063/1.335809

出版商:AIP    

年代:1985

数据来源: AIP