Formation of compressively strained Si/Si1−xCx/Si(100) heterostructures using gas-source molecular beam epitaxy

Growth of strained Si/relaxed SiGe heterostructures on Si(110) substrates using solid-source molecular beam epitaxy

“…In [15], it was also demonstrated that the strained Si layer formed on strain-relaxed SiGe/Si(110) heterostructures behaved very well as a surface channel of pMOSFET. These experimental results are consistent with a result of calculation which indicates that the hole effective mass in the Si film having the (110) surface significantly reduces when a tensile in-plane strain is applied [16]. However, application of strain by use of heterostructure necessarily requires the introduction of crystalline defects which adjust differences in the lattice constants of the constituent layers.…”

Compressively strained Si/Si1− xCx heterostructures formed on Ar ion implanted Si(100) substrates

“…It is known that the introduction of an in-plane compressive strain at more than 0.5% can reduce the hole effective mass sufficiently. 2,9) Such compressively strained Si is obtained by crystal growth on the 40-nm-thick Si 0.984 C 0.016 layer by utilizing Ar ion implantation although a Si 0.984 C 0.016 thickness of 160 nm is required for introduction of the same strain in case of the sample without ion implantation. This result manifests that the incorporation of interstitial C atoms into the substitutional sites is very crucial for obtaining a large compressive stress in the top Si layers.…”

“…According to theoretical calculations, the compressively strained Si channels with biaxial strain are expected to reduce hole effective mass, resulting in enhancement of hole mobility. 2,8,9) Compressive strain in a Si layer can be introduced by epitaxial growth on a relaxed Si 1−x C x layer, which has a smaller lattice constant than Si, and therefore, the amount of the strain is determined by the relaxation ratio and the substitutional C concentration in the Si 1−x C x layer. There are only a few reports on the fabrication of the relaxed Si 1−x C x layers on the Si substrates [10][11][12] although the precipitation of the C atoms in the strained Si 1−x C x layer has been widely studied.…”

“…There are only a few reports on the fabrication of the relaxed Si 1−x C x layers on the Si substrates [10][11][12] although the precipitation of the C atoms in the strained Si 1−x C x layer has been widely studied. [13][14][15][16] In the previous work, we have fabricated compressively strained Si=Si 1−x C x heterostructures using a gassource molecular beam epitaxy (MBE) 9,17) and investigated the effect of the gas flow rate and the growth temperature on the crystalline structure and non-substitutional C concentration in Si 1−x C x layers. We have shown that crystal growth at lower temperature is desirable for the formation of Si channels with large compressive strain since the substitutional C concentration in the Si 1−x C x layers is decreased at higher temperature due to generation of carbon-related complexes or β-SiC nanocrystals.…”

Chemical vapor deposition of Si:C and Si:C:P films—Evaluation of material quality as a function of C content, carrier gas and doping

“…Unlike SiGe films where relaxation usually happens through misfit formation and propagation, in the Si:C:P films, the propagation of misfit dislocations is hindered by the presence of C [38]. Hence the alternate way of relaxation would be to form stacking faults (C precipitation is an unlikely relaxation which cannot happen at the current growth temperatures).…”