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A detailed investigation of the Ge concentration in implanted samples has been carried out by SIMS and the effects affecting the depth distribution and measurement results have been determined. It is found that the MCs+ SIMS technique is best suited to investigate Gex(4H-SiC)1-x solid solutions up to x=0.2, while the O2+ SIMS configuration is limited to x=0.1. The Ge concentrations obtained by SIMS are very close to the nominal values. On the opposite, performing a comparison with previous RBS data, we find that the RBS values are systematically underestimated by ~30%. Finally, at very high dose, we find that some of the implanted species are lost by recoil and sputtering effects.

One of the main challenging tasks in the prospective technology is the buckling suppression of the 3C-SiC film due to the melting and solidification process and the stress relief as a consequence of the short time Si melting during the Flash Lamp Annealing. To overcome this effect and to stabilize a flat surface morphology an alternative i-FlASiC process was developed. This work refers to the influence of the layer stack modifications by doping and meltstop formation by ion implantation on the wafer buckling. The samples were studied by transmission electron microscopy, high resolution x-ray diffraction and infrared ellipsometry. The aim was to optimize the doping and flash lamp annealing conditions in relation to the i-FLASiC layer stack modification.

Pseudomorphic 4H-(Si1-xC1-y)Gex+y solid solutions were formed by ion implantation at 600°C and rapid thermal annealing at implanted Ge concentrations below 10%. At higher implantation doses followed by annealing 3C-SiC inclusion and SiGe precipitates are formed. Transmission electron microscopy investigations accompanied with “atomic location by channeling enhanced microanalysis” of the annealed samples revealed an increasing incorporation of Ge on Si lattice sites.

The properties of germanium implanted into the SiO2 layers in the vicinity of the bonding interface of silicon-on-insulator (SOI) structures are studied. It is shown that no germanium nanocrystals are formed in the buried SiO2 layer of the SOI structure as a result of annealing at the temperature of 1100° C. The implanted Ge atoms segregate at the Si/SiO2 bonding interface. In this case, Ge atoms are found at sites that are coherent with the lattice of the top silicon layer. It is found that the slope of the drain–gate characteristics of the back metal-oxide-semiconductor (MOS) transistors, prepared in the Ge+ ion implanted structures, increases. This effect is attributed to the grown hole mobility due to the contribution of an intermediate germanium layer formed at the Si/SiO2 interface.

The behavior of Sb and In atoms embedded into silicon-on-insulator structure (SOI) near the bonding interface was investigated as a function of annealing temperature. Two kinds of the ionimplanted SOI structures were prepared. First kind of the structures contained the buried SiO2 layer implanted with In+ and Sb+ ions near the top Si/SiO2 interface. In second kind, the ion-implanted regions were placed on each side of the bonding interface: Sb+ ions were implanted into Si film; In+ ions were implanted into SiO2 layer. Rutherford backscattering spectrometry (RBS) and crosssectional high-resolution electron microscopy (XTEM) were employed to study the properties of the prepared structures. The formation of InSb nanocrystals was observed within the SiO2 bulk from first kind of the SOI structures as annealing temperature increased to 1100o C. In the case of the double side implanted SOI structures, an increase in annealing temperature to 1100o C was accompanied by the up-hill diffusion of In atoms from the SiO2 bulk toward the bonding interface and by the endotaxial growth of InSb nanocrystals on the top Si/SiO2 interface. It was concluded from the experimental results that Sb atoms were the nucleation centers of InSb phase.

New types of substrates are needed for further scaling in CMOS microelectronics. We speculate that this new type of materials can be semiconductor heterostructure on insulator (HOI) compatible with current silicon planar CMOS technology. In this work an effect of interface mediated endotaxial (IME) growth of thin InSb film at Si/SiO2 bonded interface was experimentally observed and investigated for the first time. Joint semiconductor material stack obtained by hydrogen transfer of one layer material (silicon) and endotaxially grown second one (indium antimonide) placed initially into amorphous silicon dioxide film is presented. Thermodynamic, kinetic and lattice mismatch parameter influences on IME process are considered.

4H silicon carbide (Si1–xC1–y)Gex +y solid solutions with an average Ge incorporation on lattice sites ranging from 0.7 to 2.5 percent were formed by ion beam synthesis. RBS and RBS/C investigations revealed a decreasing Ge lattice incorporation with increasing implantation dose above 10%. The carried out rapid thermal annealing at 1300 °C reduces the residual damage, increases the lattice site occupation and led to negligible change in the concentration profiles. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

A box like Ge distribution was formed by ion implantation at 600°C. The Ge concentration was varied from 1 to 20 %. The TEM investigations revealed an increasing damage formation with increasing implantation dose. No polytype inclusions were observed in the implanted regions. A detailed analysis showed different types of lattice distortion identified as insertion stacking faults. The lattice site location analysis by “atomic location by channelling enhanced microanalysis” revealed that the implanted Ge is mainly located at interstitial positions.

An approach for the defect density reduction in 3C-SiC epitaxially grown on Si is to improve the quality of the carbonized layer during the early stage of growth. For this reason the conventional carbonization process was replaced by a slower and nearer equilibrium carbonization method. Carbon is introduced by implantation into oxide of an oxidized Si substrate, near the SiO2/Si interface, and then it is transferred to the Si surface by annealing. Good quality 3C-SiC grains are formed embedded into the Si substrate, which are absolutely flat at the SiO2/Si interface. Another advantage of the new carbonization process is the elimination of the cavities due to the suppression of Si out-diffusion.

This paper gives an insight into the thermal modeling of the i-FLASiC process, which is the flash lamp annealing of a 3C-SiC and silicon multilayer system. The model uses a standard heat flow model combined with an advanced multilayer optical model. Results from the model are consistent with experimentally observed phenomenon and have been used to explain diffusion mechanisms for the LPE of SiC.

In the present study cubic 3C–(Si1–xC1–y)Gex+y solid solutions were created by using ion beam synthesis. 3C–SiC thin layers grown on on-axis Si (111) substrates by Molecular Beam Epitaxy were implanted with Ge in order to incorporate Ge atoms in the Silicon Carbide lattice. Two series of experiments were carried out. The implantation energy was chosen to be 140 keV and 200 keV and the implantation dose 1 × 1017 cm–2 and 4.7 × 1016 cm–2 respectively. The samples were annealed under rapid thermal annealing conditions in the temperature range between 800 °C and 1300 °C. X-ray diffraction measurements indicate an enlargement of the lattice constant. The observed higher absorption in the implanted layers could be a sign of a band gap reduction as a consequence of Ge incorporation. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

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The influence of the implantation sequence on the defect and implant distribution during (SiC)1−x(AlN)xformation was studied by Rutherford backscattering spectrometry/ion channelling (RBS/C) and elastic recoil detection. It is shown that the implantation sequence aluminum followed by nitrogen lead to an improved crystallinity compared to the reverse implantation sequence for implantation temperatures above 400°C. The results obtained are discussed in relation to the defects distributions calculated by using a developed model which includes the effect of stress self-consistently.

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Amorphous silicon layers deposited by chemical vapour deposition on monocrystalline silicon substrates partly covered with silicon dioxide to produce SOI structures were epitaxially recrystallised by ion beam induced epitaxial crystallisation at 400°C after preamorphisation of the transition region layer/substrate. The implantation with a dose of 5×1017cm-2into the wafers with SOI structure resulted in a 1.5 μm wide overgrown crystalline layer.

To prove the feasibility of flash-lamp annealing of ion-implanted silicon, theoretical and experimental investigations have been performed. Detailed temperature calculations indicate that depending on the pulse length two different time-temperature regimes exist. In the heat conduction regime only the near surface region of the wafer is heated up to the necessary temperature and the annealing takes place in a time comparable to the pulse length. In the heat radiation regime the whole volume is heated nearly uniformly up to a maximum temperature and the heat is stored for a longer time. The thermally induced stiesses in the wafer are also calculated and compared to the temperature dependent yield stress. The basic experimental results have been obtained using As-implanted 〈100〉-silicon. The pulse length of the flash was 10 ms corresponding to an annealing in the heat radiation regime. The samples have been analyzed by Rutherford backscattering, sheet resistivity measurements and transmission electron microscopy. It has been found that the annealing characteristics are similar to that of conventional thermal annealing.

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Amorphous silicon layers deposited by chemical vapour deposition on monocrystalline silicon substrates were epitaxially recrystallised by ion beam induced epitaxial crystallisation at 400°C after preamorphisation of the transition region layer/substrate. In this manner, a layer with a thickness of 400 nm was recrystallised by implanting silicon ions at 330 keV with a dose of about 1×1017cm−2.

Using bulk silicon may be limited for 22 nm technological node due to silicon mobility limitation. New type of substrates needs for further scaling in CMOS microelectronics. We speculate that this new type of materials can be semiconductor heterostructure on insulator (HOI) compatible with current silicon planar CMOS technology. In this work an effect of interface mediated endotaxial (IME) growth of thin InSb film at Si/SiO2 bonded interface was experimentally observed and investigated for the first time. Joint semiconductor material stack obtained by hydrogen transfer of one layer material (silicon) and endotaxially grown second one (indium antimonide) placed initially into amorphous silicon dioxide film is presented. Thermodynamic, kinetic and lattice mismatch parameter influences on IME process are considered.