摘要:

The effect of impurities on the growth of the Pd2Si layer upon thermal annealing of a Pd film on ⟨100⟩ and amorphous Si substrates is investigated. Nitrogen and oxygen impurities are introduced into either Pd or Si which are subsequently annealed to form Pd2Si. The complementary techniques of Rutherford backscattering spectrometry, and15N(p,&agr;)12C or18O(p,&agr;)15N nuclear reaction, are used to investigate the behavior of nitrogen or oxygen and the alterations each creates during silicide formation. Both nitrogen and oxygen retard the silicide growth rate if initially present in Si. When they are initially in Pd, there is no significant retardation; instead, an interesting ‘‘snow‐plowing’’ effect of N or O by the reaction interface of Pd2Si is observed. By using N implanted into Si as a marker, Pd and Si appear to trade roles as the moving species, when the silicide front reaches the nitrogen‐rich region.

ISSN:0021-8979    

DOI:10.1063/1.334794

出版商:AIP    

年代:1985

数据来源: AIP

摘要:

Auger electron spectroscopy (AES) and electron loss spectroscopy (ELS) have been performed in order to investigate vacuum annealing effects on InP surface. Both techniques appeared suitable for detecting indium clustering induced by thermal surface decomposition through InM4.5N4.5N4.5spectrum modifications (AES) and In plasmon excitation (ELS). The formation of In microinclusions at the surface is detected by the two techniques for annealing temperature of 460±30 °C. In addition, AES shows that phosphorus has a complex behavior near the surface involving diffusion from the bulk, surface segregation, and desorption. These competitive mechanisms are shown to result in phosphorus enrichment or depletion of the surface layer depending mainly on the annealing temperature.

ISSN:0021-8979    

DOI:10.1063/1.334795

出版商:AIP    

年代:1985

数据来源: AIP

摘要:

The effect of Pt concentration in Pd thin films on the nucleation and growth of PdSi and PdxPt1−xSi (ternary monosilicide) has been investigated by transmission electron microscopy (TEM). Low concentration of Pt (10 at. %) in Pd film enhances PdSi formation at lower temperature than previously reported. It has been proposed that PdSi formation is governed by its slow nucleation. However, in our studies, the nucleation of PtSi, which is substituted for that of PdSi, triggers the subsequent PdSi growth at low temperatures. High concentration of Pt (55 at. %) in Pd‐Pt alloy film lowers the temperature of the phase transformation from metal‐rich silicide to monosilicide (PdxPt1−xSi). The temperature is the same as that of PtSi formation. In both cases, the monosilicide layers (about 20 nm) have an epitaxial relationship with (111) Si substrates.

ISSN:0021-8979    

DOI:10.1063/1.334796

出版商:AIP    

年代:1985

数据来源: AIP

摘要:

Misfit stress in InGaAs/InP heteroepitaxial structures grown by hydride‐transport vapor phase epitaxy has been studied using an x‐ray technique to measure the wafer curvature and using an x‐ray double crystal diffractometer to measure mismatches. The stress calculated from the measured radius of curvature was, in all cases, found to be smaller than the value predicted from the lattice mismatch using the simple beam theory and assuming a coherent interface. A simple argument is used to show that the parallel mismatch is directly related to the density of misfit dislocations. By taking into account both the presence of misfit dislocations and tetragonal distortion, relationships between the curvature, density of interfacial misfit dislocations, relaxed lattice mismatch, and measured tetragonally distorted vertical and parallel mismatches are derived. Predicted values for the radius of curvature agree very well with measured values. The results also indicate that in the presence of interfacial misfit dislocations the nature of the stress in the epitaxial layer is not uniquely determined by the mismatch. The stress can change sign depending upon the density of the misfit dislocations. This effect has actually been observed. The defect structure of the epitaxial layer is analyzed by Nomarski interference contrast microscopy, transmission x‐ray topography, and transmission electron microscopy. We have found that the misfit stress can be greatly relaxed in the presence of lattice defects such as stacking faults. The theoretical calculation is further generalized from the single epilayer/substrate case to ann‐layer heterostructure. The determination of the stresses in each layer and the misfit dislocation densities are discussed.

ISSN:0021-8979    

DOI:10.1063/1.334797

出版商:AIP    

年代:1985

数据来源: AIP

摘要:

Transmission electron microscopy (TEM) has been utilized to study the nickel‐silicide growth in self‐supported lateral‐diffusion, thin‐film couples by overlapping deposited layers of Ni and Si between two silicon oxide deposited films. Energy‐dispersive x‐ray spectroscopy, microdiffraction, and selected area diffraction were used to identify the Ni‐silicide phases and their crystal structures. Long‐grain growth of Ni2Si, as a result of phase‐boundary migration induced by diffusion, was observed duringinsituannealing between 500 and 750 °C in TEM. No preferred orientation or particular crystallographic relationship was found among the long grains.

ISSN:0021-8979    

DOI:10.1063/1.335482

出版商:AIP    

年代:1985

数据来源: AIP

摘要:

A pulsed proton beam was used to anneal Ir and IrxV100−xthin films deposited on Si single crystals. Compound phases were produced by local melting of the metal‐Si interface. Phase identification was carried out by x‐ray diffraction; while component distribution was determined by Auger electron spectroscopy and Rutherford backscattering spectrometry. The morphology of the silicide layers was examined using transmission electron microscopy; and Schottky barrier heights were determined by current‐voltage measurements. At intermediate deposited energy densities (∼0.5 J/cm2) a controlled interfacial reaction was observed. In the case of Ir/Si, amorphous IrSi as well as polycrystalline IrSi and Ir2Si3was detected in the reacted region. For the codeposited IrxV100−xfilm, withx=80 and 50, the interfacial layer reacting with the Si substrate maintained the Ir : V ratio of the as‐deposited film. This is in contrast to the case of furnace annealing where preferred accumulation of Ir is observed.

ISSN:0021-8979    

DOI:10.1063/1.334798

出版商:AIP    

年代:1985

数据来源: AIP

摘要:

The silicide formation with a titanium film deposited on ⟨100⟩ single‐crystal silicon, has been studied by using nuclear microanalysis, x‐ray diffraction, and transmission electron microscopy. The presence of interfacial defects and their possible role in the early stages of the reaction has been evidenced. The phase composition was dependent on the annealing temperature and time: at 550 °C only TiSi2is observed; at higher temperatures (>600 °C), a thin TiSi2layer at the interface is again observed, but Ti‐rich silicides grow on top of this layer by increasing the annealing time. For longer annealing times, all the reacted layer progressively transforms into TiSi2. The amount of reacted silicon grows with a (time)1/2law; the activation energy of 1.8 eV reported for the growth of TiSi2onto amorphous Si may be appropriate even in this case. The reaction proceeds at a rate of one order of magnitude higher than previously reported for reaction between silicon and an oxygen saturated titanium film. The kinetics seems to be controlled by silicon diffusion through the TiSi2interfacial layer.

ISSN:0021-8979    

DOI:10.1063/1.334799

出版商:AIP    

年代:1985

数据来源: AIP

摘要:

Stress and strain in single‐crystal Ge and GaAs/Ge films grown on SiO2‐coated Si substrates have been investigated through the Raman microprobe analysis. The Ge film is found to be subject to a tensile stress of (3.4–6.1)×109dyne/cm2and a strain of (2.4–4.3)×10−3without distinguished spatial variation within a SiO2island. The stress agrees well with that evaluated from the GaAs electroluminescence spectral shift with the deformation‐potential model. The strain can be attributed dominantly to the thermal expansion difference between the Ge and the substrate Si. A large Raman spectral shift to the lower frequency side and a large linewidth for Ge have been observed in the seeding opening region, which represents Ge lattice disorder in this region.

ISSN:0021-8979    

DOI:10.1063/1.334800

出版商:AIP    

年代:1985

数据来源: AIP

摘要:

A theory for small‐angle scattering from quasi‐random layered structures—for example, x‐ray scattering from oriented polymer samples—is proposed. Being truly three dimensional, it utilizes refractive index correlation functions separable along local principal coherence axes within the sample. Realistic variations in directions parallel to the local mean lamellar plane, as well as in the inequivalent direction perpendicular to it, can be taken into account. When the incident waves propagate at nonzero angles with respect to local mean lamellar planes, diffraction into larger angles parallel to the overall mean lamellar plane is increased, while diffraction into the larger scattering angles in the direction perpendicular to this plane is attenuated. A continuous‐domain model is proposed for describing these effects.

ISSN:0021-8979    

DOI:10.1063/1.334801

出版商:AIP    

年代:1985

数据来源: AIP

摘要:

Deep defect states inp‐type silicon crystals induced by plastic deformation at 750 °C are investigated by means of deep level transient spectroscopy. Several kinds of hole traps having different energy levels within the band gap are introduced simultaneously by deformation. The main three are denoted DH(0.24), DH(0.33), and DH(0.56). The hole concentration versus temperature relations in plastically deformedp‐type silicon crystals measured in a previous paper are interpreted in terms of the defect levels found in this work. Annealing behaviors of the defect states are followed and are compared with those induced by electron irradiation. DH(0.33) is proposed to be due to jogs and kinks while DH(0.24) and DH(0.56) to agglomerations of point defects that result from dislocation debris.

ISSN:0021-8979    

DOI:10.1063/1.334802

出版商:AIP    

年代:1985

数据来源: AIP