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It is well known that substitutional carbon (C) atoms can capture excess self-interstitial silicon (Si) atoms and suppress the diffusion of ion-implanted interstitial-type dopants, such as boron (B), in Si. In the case of B concentrations as high as ${\sim}1\times 10^{21}$ cm-3, the B activation ratio in Si decreases with C incorporation. Thus, many studies on stable B-containing clusters and/or precipitates in heavily doped Si with a C additive have thus far been conducted. However, the impact of the C incorporation on the activation and clustering of B atoms in Si is yet to be researched. In this work, the chemical bonding features of B and C atoms in heavily B-doped Si with different C contents after high-temperature annealing were characterized systematically by high-resolution X-ray photoelectron spectroscopy (XPS). It was found that the C incorporation enhances B-clustering at B concentrations higher than ${\sim}1\times 10^{21}$ cm-3after 1050 \mbox{\circC} spike annealing. In addition, the formation of C--B bonds with accompanying B-clustering was confirmed by photoemission measurement using a hard X-ray. As a result, the intrinsic B-diffusion was observed to be markedly suppressed by the C incorporation under thermodynamic equilibrium annealing at 1000 \mbox{\circC}.

Direct Silicon Bonded Si (DSB) technology with amorphization templated recrystallization process enables a relatively simple integration of CMOSFET using hybrid orientation bulk substrates. The absence of oxide at the bonding interface enables the change of the orientation of the donor Si film to that of the handle substrate after amorphization and recrystallzation. Therefore, an epitaxial realignment is caused by the absence of oxide at the bonding interface during the high-temperature annealing for recrystallzation. This paper describes the issues concerning the epitaxial realignment of DSB hybrid orientation bulk substrates, focusing on the pattern structure and rotation angle of donor layer and handle wafer dependence.

The behavior of nitrogen (N) atoms in plasma-nitrided silicon oxide (SiO2) formed by chemical vapor deposition (CVD) was characterized by physical analysis and from electrical properties. The changes in the chemical bonding and distribution of N in plasma-nitrided SiO2 were investigated for different subsequent processes. N-Si3, N-Si2O, and N2 are formed in a SiO2 film by plasma nitridation. N2 molecules diffuse out during annealing at temperatures higher than 900 degC. NH species are generated from N2 molecules and H in the SiO2 film with subsequent oxide deposition using O3 as an oxidant. The capacitance-voltage (C-V) curves of metal-oxide-semiconductor (MOS) capacitors are obtained. The negative shift of the C-V curve is caused by the increase in the density of positive fix charge traps in CVD-SiO2 induced by plasma nitridation. The C-V curve of plasma-nitrided SiO2 subjected to annealing shifts to the positive direction and that subjected to the subsequent oxide deposition shifts markedly to the negative direction. It is clarified that the density of positive charge fixed traps in plasma-nitrided SiO2 films decrease because the amount of N2 molecules is decreased by annealing, and that the density of traps increases because NH species are generated and move to the interface between SiO2 and the Si substrate with the subsequent oxide deposition.

Carbon doped SiGe (SiGe:C)/Si(001) heterostructure were grown by reduced pressure chemical vapor deposition using silane, germane and methylsilane as a source of Si, Ge, and C, respectively. We performed a systematic experiment of growth of SiGe:C and carried out measurements to determine the surface roughness and occupation sites of carbon atoms as functions of C source flow, Ge concentration, growth temperature and growth rate. Ge concentration range was from 0 to 23.0%. Growth temperature was 575 to 625 \mbox{\circC}. The range of Growth rate was between 1.5 and 4.3 $Å$/s. These SiGe:C analyzed by atomic force microscopy (AFM), secondary ion mass spectrometry (SIMS), high-resolution X-ray diffraction (HR-XRD) and cross-sectional transmission electron microscopy (TEM). Total C compositions did not depend on growth temperature with the constant Ge concentration and with SiH3CH3flow ratio. Surface roughness of SiGe:C with high Ge concentration increased with the increase of C source gas flow. Interstitial C concentration in SiGe:C films with rough surface increased with the increase of C source gas flow. The roughness of SiGe:C layer grown constant C gas source flow ratio decreased for low growth temperature and/or faster growth rate. From these results, we revealed that the mechanism of defect formation with localized C as the cause of rough. The excess migration can suppress surface roughness.

It is well-known that the coimplantation of carbon (C) in a concentration range comparable to the range of boron (B) concentrations could suppress B diffusion, resulting in a boxlike B profile. Substitutional C atoms can capture excess self-interstitial Si atoms and suppress the diffusion of ion-implanted intersitial-type dopants such as B in silicon (Si). However, the effect of C on activation properties in wide C and B concentration ranges has not been sufficiently investigated. In this work, in the experiment in wide C and B concentration ranges, it was clarified for the first time that the B activation ratio of Si increases or decreases varies depending on the concentration of C incorporated. The activation ratio of the B activation layer was increased markedly by C incorporation in the case of light B implantation such as in the concentration range of $8\times 10^{19}$ to $3\times 10^{20}$ cm-3. This might be attributed to the interaction of C with Si interstitials and the suppression of the boron Si-interstitial clustering induced by C incorporation. In contrast, in the case of heavy B implantation such as at a $1\times 10^{21}$ cm-3concentration, the activation ratio was decreased slightly by C incorporation. When stable B-containing clusters and precipitates were formed at high B concentrations, the effect of C incorporation on activation ratio was considered to be small.

Since the lattice constant of silicon-carbon (Si:C) is smaller than that of Si, Si:C embedded in the source and drain (e-Si:C S/D) can induce tensile stress in the channel and improve the electron mobility of n-metal--oxide--semiconductor field-effect transistor (nMOSFETs). In this research, molecular carbon (C) ion implantation and recrystallization schemes employed to achieve strained Si:C films with a high substitutionally incorporated carbon concentration ([C]\text{sub) and a high ratio of substitution were studied. Several recrystallization techniques including rapid-thermal-annealing (RTA)-based solid phase epitaxy (SPE), spike annealing, and nonmelt laser annealing have been used to optimize C incorporation into Si and strain application. Results of these different implantation and annealing techniques are compared and discussed. Furthermore, we proposed the first recrystallization by nonmelt laser annealing and the co-incorporation of a dopant that increases the rate of Si regrowth and has a covalent radius slightly different from that of Si. These processes markedly promoted the recrystallization of C densely incorporated in an amorphous Si layer and improved the crystallinity of strained Si:C films while maintaining a high [C]\text{subat a high ratio of substitution.

Direct Silicon Bonded Si (DSB) technology with amorphization templated recrystallization process enables a relatively simple integration of CMOSFET using hybrid orientation bulk substrates. The absence of oxide at the bonding interface enables the change of the orientation of the donor Si film to that of the handle substrate after amorphization and recrystallzation. Therefore, an epitaxial realignment is caused by the absence of oxide at the bonding interface during the high-temperature annealing for recrystallzation. This paper describes the issues concerning the epitaxial realignment of DSB hybrid orientation bulk substrates, focusing on the pattern structure and rotation angle of donor layer and handle wafer dependence.