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Presents information on a study which examined the evolution of both {311} defects and dislocation loops in the end-of-range (EOR) damage region in silicon amorphized by ion implantation. Two evolutionary pathways for {311} defects; Preferential site for dislocation loop nucleation.

Studies the perturbance in silicon vacancy concentration induced by the presence of TiSi2 films. Use of antimony in silicon doping as vacancy detector; Stress compensation mechanism; Volume contraction mechanism.

Abstract: The kinetics of stressed solid-phase epitaxial growth (SPEG), also referred to as solid-phase epitaxy, solid-phase epitaxial regrowth, solid-phase epitaxial recrystallization, and solid-phase epitaxial crystallization, of amorphous (α) silicon (Si) created via ion-implantation are reviewed. The effects of hydrostatic, in-plane uniaxial, and normal uniaxial compressive stress on SPEG kinetics are examined in intrinsic (001)Si. Particular emphasis is placed on unifying the results of different experiments in a single-stress-dependent SPEG model. SPEG kinetics are observed to suffer similar exponentially enhanced growth rates in hydrostatic and normal uniaxial compressive stress. However, there are discrepancies between researchers in terms of the influence of in-plane stress on growth rates. Two different stress-dependent SPEG models are thus advanced, each with different physical bases. The model advanced by Aziz et al. proposes SPEG can be modeled as a single-atomistic process while the model advanced by Rudawski et al. suggests that stress influences the nucleation and migration processes of growth differently and that SPEG cannot be modeled as a single step. The basis for the Rudawski et al. model is based on the crystal island and ledge migration model of SPEG advanced by others. Morphological instabilities of the growing α/crystalline interface with in-plane compression are also addressed within the context of both the Aziz et al. and Rudawski et al. models. Finally, using the Rudawski et al. model, it is possible to examine, characterize, and isolate the different atomistic processes during growth. Calculation of the activation energies for nucleation and migrations processes suggests that the activation energy of 2.7eV observed for the growth rate in stress-free SPEG by Olsen and Roth is representative of the activation energy for the single-atomistic process of crystal island nucleation. Thus, the study of stressed SPEG provides a new atomistic picture of the nature of growth. [Copyright &y& Elsevier]

The reaction kinetics of {3 1 1} defect dissolution in SIMOX, SOITEC and bulk silicon materials have been investigated. The effects of implant energy and surface silicon thickness on the activation energy for {3 1 1} dissolution have been measured using quantitative TEM (QTEM). SOI wafers having surface silicon thickness of 750 and 1450 A˚ were implanted with Si+ ions at 15–48.5 keV, 1×1014 cm−2. Furnace and RTA anneals were performed at temperatures ranging from 700 to 825 °C. Quantitative TEM was used to monitor the trapped interstitial dose in {3 1 1} defects. The activation energy for {3 1 1} dissolution was found to decrease as the surface silicon thickness decreased, suggesting a lower activation barrier as the implant damage approaches the surface silicon/buried oxide (BOX) interface. However, the 1450 A˚ SOI had similar dissolution kinetics to the bulk silicon for all of the implants studied suggesting the reduced activation barrier is likely due to recombination at the surface Si/BOX interface. [Copyright &y& Elsevier]

Investigates the lattice strain and defect formation in oxygen-implanted silicon by high-resolution x-ray diffraction. Formation of vacancy-typed defects with high density; Reduction of the negative strain; Production of low-threading dislocation density; Relaxation of the stringent condition.

Examines the low energy and low dose B[sup +]-implanted silicon. Use of transmission electron microscopy and secondary ion mass spectroscopy; Integration of B with silicon self-interstitialis from {311} defect dissolution; Effect of extrinsic defects on energy configuration for accommodating excess interstitialis.

Reports on the growth by organometallic vapor phase epitaxy high-purity InP on Si substrates using a GaAs intermediate layer. Residual electron concentration exhibited by the InP layers; Electrical properties.

Abstract: The relaxation process of ion-implanted strained silicon films grown on silicon-rich relaxed Si1−x Ge x alloys was studied to determine the critical strain regime necessary for the breakdown of solid phase epitaxial recrystallization. Experimental structures were grown via molecular beam epitaxy (MBE) and contained a 50nm strained silicon capping layer on relaxed Si1−x Ge x . The relaxed Si1−x Ge x alloy compositions range from 0 to 30at.% germanium. A 12keV Si+ implant at a fluence of 1×1015 atoms/cm2 was used to generate an amorphous layer ∼30nm thick, confining it to the strained silicon cap. The degree of relaxation of the silicon cap layer was quantified by high-resolution X-ray diffraction (HRXRD) omega–2theta rocking curves and reciprocal space maps. Maps were acquired for the (004) and (113) reflections to obtain the in and out-of-plane lattice parameter of the layers. Upon annealing, the solid phase regrowth (SPER) process broke down for the highest level of strain. Additionally, regrowth related defects were observed in these samples using cross-sectional transmission electron microscopy (XTEM). These results indicate a reduction of strain in the Si0.7Ge0.3 samples occur as a result of SPER breakdown that generated dislocations and stacking faults throughout the silicon capping layer. [Copyright &y& Elsevier]

GaAs is a material of interest as a potential buffer layer in future III–V semiconductor-based transistor technologies integrated on Si wafers. The goal of this study was to investigate the effect of growth temperature on the propagation and annihilation of antiphase domain boundaries (APBs) in GaAs films grown on Si(001) by metal-organic chemical vapor deposition (MOCVD). No intentional wafer off-cuts or high temperature pre-growth anneals (>1000 °C) were employed as both of these practices complicate integration with other devices. To evaluate the role of growth temperature on the APB evolution, a 200 nm thick layer of GaAs was grown on the Si at a fixed temperature of 530 °C so that all samples started with the same approximate APB density. Subsequently, 600 nm of GaAs was grown at temperatures varying between 530 °C and 650 °C. Chemical etching combined with scanning electron microscopy (SEM) was used to profile the density of the APBs in each sample as a function of depth. The APB annihilation rate, i.e. the exponential decay rate of APB density with respect to film thickness, increases from 2.6 μm −1 to 10.7 μm −1 as the growth temperature increases from 530 °C to 610 °C and then saturates. The increase in annihilation rate with increasing temperatures suggests that the higher temperatures remove kinetic barriers to the reduction of the overall APB interfacial area. An activation energy of 1.1 eV was extracted using an Arrhenius relationship and likely corresponds to the energy needed for APBs to kink from {110} to higher-index planes, e.g. {112}. Dark field transmission electron microscopy showed that at higher growth temperatures the APBs can shift from vertical {110} habit planes to {112} planes leading to self-annihilation with sufficient thickness. [ABSTRACT FROM AUTHOR]