Showing papers on "Annealing (metallurgy) published in 1980"
TL;DR: In this paper, the dopant segregation at grain boundaries in polycrystalline silicon has been investigated, and a theory of segregation in systems of small particles has been developed, using this theory, the heat of segregation of arsenic and phosphorus, and the number of active dopant atoms within the grain boundaries as a function of annealing temperature.
Abstract: Dopant segregation at grain boundaries in polycrystalline silicon has been investigated. Arsenic, phosphorus, and boron were ion implanted into low‐pressure, chemically‐vapor‐deposited polycrystalline‐silicon films. All films were then annealed at 1000 °C for 1 h, and some were subsequently further annealed at 800, 850, or 900 °C for 64, 24, or 12 h, respectively. For phosphorus and arsenic the room‐temperature resistivity of the films was found to be higher after annealing at lower temperatures. By successively annealing the same sample at lower and higher temperatures, the resistivity would repeatedly increase and decrease, indicating reversible dopant segregation at the grain boundaries. Hall measurements were used to estimate the number of active dopant atoms within the grains and the number of atoms segregated at the grain boundaries as a function of annealing temperature. A theory of segregation in systems of small particles has been developed. Using this theory, the heat of segregation of arsenic and phosphorus in polycrystalline silicon was calculated. For boron no appreciable segregation was observed.
347 citations
TL;DR: In this article, a model based solely on a threefold coordinated random network structure was presented to explain the diamond-like physical properties of a-C films and their changes with annealing.
Abstract: Evaporated and sputtered a-C films deposited at L.N. temperature were prepared and studied as a function of annealing using Raman, electron energy loss, and ESR techniques. The reduced Raman spectra of virgin films reflect the one phonon density of states of graphite. Moreover, no evidence for diamond bonding is found from the electron energy loss experiment. Upon annealing, graphitic structural correlations develop within bounded islands of carbon atoms. This picture is consistent with ESR measurements which yield 3 × 1019 spins/cm3 independent of annealing but a resonnance line (g = 2.002 ± .0005) that narrows with annealing. A model based solely on a three-fold coordinated random network structure will be presented to explain the “diamond-like” physical properties of a-C films and their changes with annealing.
345 citations
TL;DR: In this article, the formation of supersaturated substitutional alloys by ion implantation and rapid liquid phase-epitaxial regrowth induced by pulsed laser annealing has been studied using Rutherford backscattering, ion channeling analysis.
Abstract: The formation of supersaturated substitutional alloys by ion implantation and rapid liquid‐phase‐epitaxial regrowth induced by pulsed laser annealing has been studied using Rutherford backscattering, ion channeling analysis. Group‐III (Ga, In) and group‐V (As, Sb, Bi) dopants have been implanted into single‐crystal silicon at doses ranging from 1×1015 to 1×1017/cm2. The samples were annealed with a Q‐switched ruby laser (energy density ∼1.5 J/cm2, pulse duration ∼15×10−9 sec). Ion channeling analysis shows that laser annealing incorporates these dopants into substitutional lattice sites at concentrations far in excess of the equilibrium solid solubility. Channeling measurements indicate the silicon crystal is essentially defect free after laser annealing. Also values for the maximum dopant concentration (Cmaxs) that can be incorporated into substitutional lattice sites are determined for our annealing conditions. Dopant profiles determined by Rutherford backscattering are compared to model calculations wh...
311 citations
TL;DR: In this article, a detailed study of interdiffusion in (GaAs)n(AlAs)m multilayer structures grown by molecular beam epitaxy was made, where the time dependence of the Fourier components of the composition modulation at a constant annealing temperature was obtained by measuring the intensities of the superlattice satellites by x-ray diffraction.
Abstract: A detailed study has been made of interdiffusion in (GaAs)n(AlAs)m multilayer structures grown by molecular beam epitaxy. The subscripts n and m indicate that the structure is a repeating sequence of n monolayers of GaAs followed by m monolayers of AlAs. The time dependence of the Fourier components of the composition modulation at a constant annealing temperature was obtained by measuring the intensities of the superlattice satellites by x‐ray diffraction. For a sample with (n,m) = (12,9) at a temperature of 860 °C, the data can be fit by a composition‐dependent diffusion coefficient of the form D (C) =8.8×10−20 exp(αC) cm2/sec, where α=2.06 and C is the gallium concentration. The parameter α is proportional to the difference in the diffusion activation energy in GaAs and AlAs. An α of 2.06 at 860 °C corresponds to an energy difference of 0.201 eV. Calculations which assume vacancy diffusion via the arsenic sublattice give an energy difference of 0.25 eV in reasonable agreement with the experimental valu...
243 citations
TL;DR: In this article, the authors showed that the hillock formation observed in the present case has been explained on the basis of thermal stress relaxation occuring by diffusion creep, with the additional effect of the high surface diffusion of silver atoms on an oxygen-covered silver surface.
187 citations
TL;DR: The equilibrium shape of gold crystallites on a graphite cleavage surface has been studied in this paper, where the crystallites (a few μm in diameter) were obtained by annealing a continuous gold film under U.H.V. for about 70 h at 1273 K.
177 citations
TL;DR: In this article, it was found that polycrystalline films are formed above 600°C and are more stable than the amorphous films deposited at lower temperatures, depending primarily on the deposition temperature.
Abstract: Silicon films deposited by low pressure chemical‐vapor deposition over the temperature range from 525° to 725°C were investigated. It was found that polycrystalline films are formed above 600°C and are more stable than the amorphous films deposited at lower temperatures. Their crystal structure is a strong function of the deposition temperature and a weaker function of the deposition rate. Either the {110} or the {100} texture may dominate the structure, depending primarily on the deposition temperature. The electrical resistance obtained on doping the LPCVD films that are polycrystalline as deposited is maximum for films deposited at the lower temperatures (near 600°C), although this dependence on deposition temperature decreases after annealing at higher temperatures. Dopant atoms reversibly segregate to the grain boundaries during lower temperature heat‐treatments subsequent to doping and are dispersed at higher temperatures, with corresponding changes in resistivity. The oxidation rate is only a weak function of the deposition temperature, although the initially amorphous films may oxidize somewhat more rapidly. The index of refraction of amorphous films is significantly higher than that of polycrystalline films.
155 citations
TL;DR: In this paper, the growth of CoSi2 films on Si substrates and Si films on the Si(111)/CoSi2 structure are investigated and two dominant factors required to obtain good epitaxial films are substrate cleaning by lamp heating before the film deposition and annealing of the deposited films without exposure to air.
Abstract: Epitaxial growth of CoSi2 films on Si substrates and the growth of Si films on the Si(111)/CoSi2 structure are investigated. Solid phase epitaxy is used to grow both CoSi2 and Si films. Molecular beam epitaxy is also used to grow the top Si films in the double heteroepitaxy. It has been found that two dominant factors required to obtain good epitaxial films are substrate cleaning by lamp heating before the film deposition and annealing of the deposited films without exposure to air. Excellent crystalline quality of the CoSi2 films on (111) Si substrates and good quality of the Si films on the Si(111)/CoSi2 structure have been demonstrated by ion channeling and backscattering techniques and reflection electron diffraction analysis. Uniformity of the grown films has also been examined by scanning electron microscopy.
151 citations
TL;DR: In this article, a microprobe Auger spectrometer and an x-ray diffractometer were used to investigate the alloying behavior of thin Ni/Au-Ge films on a GaAs substrate.
Abstract: Alloying behavior of thin Ni/Au‐Ge films deposited on a GaAs substrate is investigated by using a microprobe Auger spectrometer and an x‐ray diffractometer. The deposited films react with the substrate above 300 °C to form alloys with complex multilayer structure in the 300–400 °C temperature range and alloys with microscopic grain structure above 450 °C. Uniform alloying, accompanied with a smooth interface, is observed and is ascribed to the high reactivity of Ni with GaAs under a solid‐solid phase. However, when the sample is annealed in the solid‐solid phase, Ni penetrates irregularly into the GaAs substrate, if the annealing duration is too long, causing poor Ohmicity. Rapid Ge moving to the substrate interface is observed at 400 °C and is closely related to the formation of a Ge‐doped degenerate layer beneath the contact. The high reliability of the contract, which is obtained when annealed at 500 °C, is explained by the metallurgical stability of the grain structure. Based on the results of this study, some rules for III‐V compound semiconductor contact fabrication are proposed.
135 citations
TL;DR: In this article, the influence of oxygen on the resistivity of dislocation-free silicon wafers was studied after annealing at various temperatures under a nitrogen ambient, and significant resistivity shifts were observed in the temperature range 600 −900°C and related to oxygen precipitation.
Abstract: The influence of oxygen on the resistivity of dislocation‐free silicon wafers was studied after annealing at various temperatures under a nitrogen ambient. Significant resistivity shifts were observed in the temperature range 600–900 °C and related to oxygen precipitation. This phenomenon is independent of the well‐known donor generation observed around 450 °C and is more difficult to cure.
132 citations
TL;DR: In this article, the melting temperature and the heat of melting increased on annealing time and temperature from 174 °C and 10 cal/g to 187 °C, and at the same time the long period was enhanced from 80 to 160 A.
Abstract: Thermal and crystalline behaviour of nylon 12 annealed at low supercooling for 10–2500 hours were studied by DSC, SAXS, WAXS and electron microscopy. The melting temperature and the heat of melting increased on annealing time and temperature from 174 °C and 10 cal/g to 187 °C and 23 cal/g, and at the same time the long period was enhanced from 80 to 160 A. Long time annealing caused a partial transformation of theγ-crystal structure to theα-crystalline modification.
TL;DR: In this paper, a method to anneal implanted silicon wafers in a few seconds using a halogen lamp as a radiation source was proposed, and the activation of implanted boron was determined by the maximum temperature during annealing.
Abstract: A new method to anneal implanted silicon wafers in a few seconds using a halogen lamp as a radiation source is proposed. Boron-implanted (200 keV, 1×1013 cm-2) silicon wafers were completely activated with little diffusion by radiation for 6 seconds. Conventional annealing for 15 minutes caused diffusion of boron. It was found that the activation of implanted boron was determined by the maximum temperature during annealing.
TL;DR: In this article, the authors measured the interdiffusivity in compositionally modulated (λ≈25 A) amorphous (Pd85Si15)61/(Fe85B15)89 and Pd80Au7Si13)70/Fe30 films by monitoring the satellite of the (000) x-ray scattering peak during isothermal anneals in the range 210-250 °C.
Abstract: The interdiffusivity in compositionally modulated (λ≈25 A) amorphous (Pd85Si15)61/(Fe85B15)89 and (Pd80Au7Si13)70/Fe30 films has been measured by monitoring the satellite of the (000) x‐ray scattering peak during isothermal anneals in the range 210–250 °C. Diffusivities as low as 10−22 cm2 s−1 have been measured. It was observed that the diffusivity decreased continuously during the annealing as a result of structural relaxation and settled down to a constant value only after many hours of annealing. The activation energy of the isoconfigurational diffusivity in the Pd‐Au‐Si/Fe films is 167 kJ mol−1. This value and the time scale of the relaxation are similar to those observed in earlier viscosity measurements, indicating a similarity between the structural defects controlling both transport processes.
TL;DR: In this article, annealing experiments on defects produced by 1 −MeV electron irradiation at room temperature have been performed on n-type GaAs (vapor phase epitaxy layers).
Abstract: Isochronal and isothermal annealing experiments on defects produced by 1‐MeV electron irradiation at room temperature have been performed on n‐type GaAs (vapor phase epitaxy layers). In addition to the previously reported irradiation‐induced defects E2 to E5, three new traps have been observed (P1 to P3) and their thermal behavior has been studied together with the thermal behavior of the traps E2–E5. The trap E2 is shown to exhibit an annealing kinetics which can be decomposed into the sum of two first‐order kinetics, the first one having the same annealing rate as the annealing kinetics of the traps E3 and E5. These observations lead to an interpretation of the annealing mechanism: annihilation of vacancy‐interstitial pairs or vacancy‐antisite defect pairs, and E2 is tentatively identified as a vacancy.
TL;DR: The phenomenological features of liquid metal embrittlement (LME) are reviewed and the influence of metallurgical factors and testing conditions is described in this article, where various theories have been considered and it is concluded that a reduction in surface energy leading to lower crack-tip cohesion and hence lower plastic deformation is consistent with most of the experimental evidence.
TL;DR: In this paper, the effect of argon ion bombardment during the evaporation procedure was studied experimentally, and it was shown that the small amount incorporated into the film by the bombardment is shown to have no significant influence on the process.
TL;DR: In this article, the oxide precipitate growth mechanism in Czochralski silicon was investigated using highvoltage electron microscopy (HVEM) and it was found that the precipitate proceeds two-dimensional growth of a square-shaped plate without observable thickening.
TL;DR: In this article, the annealing properties of pure and antimony-doped tin oxide films were reported up to temperatures of approximately 400°C in various atmospheres and it was found that the chemisorption or desorption of oxygen, primarily from the grain boundaries, governs the changes in the electrical parameters of the films.
TL;DR: In this article, an ambient effect on the precipitation of oxygen in the bulk of silicon wafers was found to strongly retard the precipitation, in comparison with various inert ambients.
Abstract: We have discovered an ambient effect on the precipitation of oxygen in the bulk of silicon wafers. Oxidizing ambients were found to strongly retard the precipitation, in comparison with various inert ambients. The precipitation process was studied by the methods of infrared spectrophotometry, thermal conversion, and transmission electron microscopy. In oxidizing ambients, oxygen precipitates tended to cluster in colonies. A typical colony consisted of a few to tens of precipitates, webbed in a complex of dislocation loops. In contrast, precipitates formed in inert ambients were usually isolated. Two mechanisms are suggested to explain this effect, both involving oxidation‐generated silicon self‐interstitials.
TL;DR: The recycling methods of the author and Ortho-Bonding caused a loss of ferromagnetism in the recycled brackets, suggesting annealing of the metal, and changes in the metallurgic microstructure suggest susceptibility to metallic intergranular corrosion.
TL;DR: In this paper, sputtered titanium-nitride layers have been incorporated as diffusion barriers in a titanium-silver metallization scheme on silicon, Backscattering analysis (2-MeV He+, RBS) indicates that the integrity of the system is basically preserved during annealing at 600° for 10 min.
Abstract: Reactively sputtered titanium-nitride layers have been incorporated as diffusion barriers in a titanium-silver metallization scheme on silicon, Backscattering analysis (2-MeV He+, RBS) indicates that the integrity of the system is basically preserved during annealing at 600° for 10 min. Electrical properties were determined for titanium-nitride layers prepared under different deposition conditions. Resistivity and Hall mobility appear to depend on the oxygen contamination of the deposited material. For the lowest oxygen concentration (<5 at %) a resistivity of 170 µΩ . cm has been found.
TL;DR: In this article, the diffusion behavior of implanted boron in silicon was investigated using the 10B(n,α)7 Li nuclear reaction, and an anomalous behavior with a strong reduction of the diffusivity above an effective solubility limit at 1.5×1019, 6 ×1019 and 1.1×1020 cm−3 was found for annealing temperatures of 800, 900, and 1,000°C, respectively.
Abstract: The diffusion behaviour of implanted boron in silicon was investigated using the10B(n,α)7 Li nuclear reaction. An anomalous behavior with a strong reduction of the diffusivity above an effective solubility limit at 1.5×1019, 6×1019, and 1.1×1020 cm−3 was found for annealing temperatures of 800, 900, and 1,000°C, respectively.
TL;DR: In this article, the role of average deposited energy density θ υ in determining the characteristics of the damaged regions was investigated using transmission electron microscopy, and both monatomic and diatomic ions were used in order to investigate the role and properties of damaged regions in low fluence (1011-1012 ions cm−2) ion bombardments.
TL;DR: In this paper, the surface conductivity and work function were measured after annealing at elevated temperatures in UHV and after adsorption of atomic hydrogen, and it was concluded that the two clean cleaved polar faces exhibit a depletion layer.
TL;DR: In this article, both n and p-type ion-implanted GaAs and InP have been annealed at temperatures up to 880 and 760°C, respectively, using a "close contact" capless annealing technique.
Abstract: Both n‐ and p‐type ion‐implanted GaAs and InP have been annealed at temperatures up to 880 and 760 °C, respectively, using a ’’close‐contact’’ capless annealing technique. In this annealing process the flat, implanted surface of the semiconductor is placed in close contact with another flat surface, usually a Si3N4 encapsulated identical semiconductor. Samples annealed in such a proximity manner show no detectable sign of decomposition and exhibit state of the art electrical performance. This is the first report of successful capless annealing of InP.
TL;DR: In this paper, the high strength of the mechanically alloyed aluminum is due to a dispersion of both γ-Al2O3 and Al4C3 particles with sizes of the order of 10 nm.
Abstract: Dispersion strengthened aluminum has been produced by mechanical alloying (high energy ball milling) and subsequent extrusion. The production process was modified in several ways in order to determine the changes of the dispersoid structure during annealing. As such, extrusion was performed cold and milling was conducted in part without lubrication. The high strength of the mechanically alloyed aluminum is due to a dispersion of both γ-Al2O3 and Al4C3-particles with sizes of the order of 10 nm. The dispersoids are amorphous after milling and crystallize during heating in the temperature range of 400 to 500 °C (673 to 773 K). The crystallization coincides with an increase of the room temperature hardness of the material. Possible techniques for improving dispersion strengthened materials have been considered and are discussed.
TL;DR: In this article, the intrinsic gettering phenomenon was found to be correlated with the annealing temperature and the defect types (dislocations, precipitates, and stacking faults) and defect structures as well as nature.
Abstract: Surface‐ and inner‐microdefects examined after a two‐step annealing process are compared and related to the intrinsic gettering phenomenon. After the defects are characterized by means of transmission electron microscopy, the defect types (dislocations, precipitates, and stacking faults) and defect structures as well as nature are correlated with the annealing temperature. It is found from the observations that a surface‐microdefect is a stacking fault extrinsic in nature possibly caused by a process‐induced ’’heavy metal contamination’’ such as copper and that the type of Si‐O complex precipitates generated strongly depends on annealing temperatures: <1050°C⋅⋅⋅ platelike cristobalite, 1100°C<⋅⋅⋅ regular octahedral amorphous SiO2. In addition, the mechanism for the formation of these defects is discussed based on electron microscope observations.
TL;DR: In this paper, a correlation between three types of measurement technique was established and four distinct annealing stages have been identified for perfect recrystallization and maximum electrical activation in GaAs with 150 keV, 1.10 15 zinc ions and furnace annealed in the temperature range from room temperature to 900°C.
Abstract: Electrical, Rutherford backscattering and transmission electron microscopy measurements have been carried out on GaAs samples implanted with 150 keV, 1.10 15 zinc ions/cm 2 and furnace annealed in the temperature range from room temperature to 900°C. A correlation between three types of measurement technique was established and four distinct annealing stages have been identified. For perfect recrystallization and maximum electrical activation an annealing temperature of 900°C is required. The maximum peak hole concentration was in the range 1–2.10 19 holes/cm 3 .
TL;DR: In this paper, the authors studied the room temperature dependence of the stress-induced magnetic anisotropy in Co 73 Mo 2 Si 15 B 10 (λ s 0.89 Fe 0.11 ) 72 Mo 3 Si 15B 10(λ > 0) metallic glass ribbons and concluded that transient creep and steady-state creep at the elevated temperature give rise to compressive and tensile stresses, respectively, in the expression for the magnetoelastic coupling energy at room temperature.
TL;DR: In this article, the nucleation rate of oxide precipitates in silicon at 750°C was determined by two-step annealing and through transmission electron microscopy, where the precipitates were of two kinds: (a) grown from microprecipitates which existed in as-grown crystals, and (b) grown nuclei which nucleated during the annoaling.
Abstract: The nucleation rate of oxide precipitates in silicon at 750 °C was determined by two‐step annealing and through transmission electron microscopy. The density of oxide precipitates was found to increase by annealing in proportion to annealing time. The precipitates were of two kinds: (a) grown from microprecipitates which existed in as‐grown crystals, and (b) grown nuclei which nucleated during the annealing. The nucleation rate was obtained by discriminating (b) from (a) to be about 107 cm−3 sec−1 for an oxygen content of 11×1017 atoms cm−3. Using this result and classical nucleation theory, homogeneous nucleation mechanism of oxygen precipitation is discussed.