A theoretical model for threading dislocation reduction during selective area growth

Reduction of Threading Dislocation Density in Sputtered Ge/Si(100) Epitaxial Films by Continuous-Wave Diode Laser-Induced Recrystallization

“…After laser annealing at 73 J/cm 2 below the Ge melting point, the TDD of Ge is reduced to 10 8 –10 9 cm –2 , which is in a similar range to that obtained by conventional thermal annealing . In this case, the dislocations within the Ge film are thermally activated to glide and can annihilate when having opposite Burger vector and are within an annihilation radius . When the laser dose is increased to 78 J/cm 2 that is able to melt the Ge film, the TDD is dramatically reduced by more than 3 orders of magnitude to 10 6 –10 7 cm –2 .…”

Thin Ge buffer layer on silicon for integration of III-V on silicon

“…The next part of the annealing study focused on the impact of replacing the continuous 30 min annealing cycle with a periodic one consisting of five 5-minute anneals between high temperature (TH) of 850°C and low temperature (TL) of 450°C. The TEM results show a further small reduction in TDD which attributes to the TD glide and annihilation caused by thermal stress when cooling down and heating up [22,23]. The AFM images also show a slight improvement in the surface smoothness of the sample.…”

Low surface roughness and threading dislocation density Ge growth on Si (001)

“…Furthermore, HT annealing helps not only in smoothing the surface but also in causing the threading dislocations to propagate towards the edge of the substrate. This propagation is due to the presence of tensile strain caused by linear thermal expansion coefficient difference [2,16]. The thermal expansion coefficients of Ge and Si are 6.0 and 2.6 mm m À1 K À1 at room temperature, respectively.…”