Relaxed Ge0.9Si0.1 alloy layers with low threading dislocation densities grown on low-temperature Si buffers

Abstract

Relaxed GexSi1−x epilayers with high Ge fractions but low threading dislocation densities have been successfully grown on Si (001) substrate by employing a stepped-up strategy and a set of low-temperature GeySi1−y buffers. We show that even if the Ge fraction rises up to 90%, the threading dislocation density can be kept lower than 5×106 cm−2 in the top layers, while the total thickness of the structure is no more than 1.7 μm.

Sb as surfactant at plastic relaxation of GeSi/Si(001) films grown by molecular-beam epitaxy: Reduction of surface roughness value

“…This was achieved by using a lowtemperature (400-450 1C) buffer layer of Si whose thickness was 50-100 nm. These results were further supported by other publications [3][4][5][6][7][8]. In addition to the threading dislocations density, another important characteristic of relaxed films is the surface roughness [9].…”

Different architectures of relaxed Si1−xGex/Si pseudo-substrates grown by low-pressure chemical vapor deposition: Structural and morphological characteristics

“…Though silicon is an indirect bandgap semiconductor, many indexed defects [26,31], especially dislocations, are radiative at low temperature [32]. The dislocations are electrically active, giving rise to D 1 -D 4 lines [26,32] and remain an issue for deep sub-90 nm complementary-metal-oxide-semiconductor technologies based on strained Si 1 À x Ge x channels [25,27].…”

Fabrication of strained-Si channel p-MOSFET’s on ultra-thin SiGe virtual substrates

“…The self-heating of the strained-Si devices arises from the lower thermal 1 [5] and results in a significantly elevated channel temperature [6] . Some attempts have been reported, such as, growth of defect-rich layers at low temperature [7] . As reporded recently, to n-MODFETs on the ultra-thin relaxed-SiGe substrates realized by helium implantation, its electron mobility is 1470cm 2 /Vs and f max 100GHz [8] .…”