Kirkendall void formation in reverse step graded Si_1−xGe_x/Ge/Si(001) virtual substrates

Abstract

Formation of Kirkendall voids is demonstrated in the Ge underlayer of reverse step graded Si 1−x Ge x /Ge buffer layers grown on Si(001) using reduced pressure chemical vapour deposition (RP-CVD). This phenomenon is seen when the constant composition Si 1−x Ge x layer is grown at high temperatures and for x0.7. The density and size of the spherical voids can be tuned by changing Ge content in the Si 1−x Ge x and other growth parameters.

The Role of Intragranular Nanopores in Capacity Fade of Nickel-Rich Layered Li(Ni1–x–yCoxMny)O2 Cathode Materials

“…Other possible explanations for the presence of nanopores include oxide–oxide solid-state reactions between different precursors during compound formation at elevated temperature. In other multicomponent systems, interdiffusion leads to nanovoid formation through the so-called Kirkendall effect. , Of note, nanopores have already been shown to exist in the NiO–CoO-O 2 system, although the actual mechanism of formation is unclear …”

“…In other multicomponent systems, interdiffusion leads to nanovoid formation through the so-called Kirkendall effect. 53,54 Of note, nanopores have already been shown to exist in the NiO− CoO-O 2 system, although the actual mechanism of formation is unclear. 55…”

Thin and locally dislocation-free SiGe virtual substrate fabrication by lateral selective growth

“…conventional graded buffers [6][7][8][9][10] and reverse graded buffers. [11][12][13][14] However, there are still several remaining problems with these methods as they require several μm thick buffer layers to reduce threading dislocation (TD) density. The distribution of TD networks in the SiGe layer causes uncontrolled random positions of the TDs.…”

Exploring Ru Compatibility With Al-Ge Eutectic Wafer Bonding

“…References [13] and [14] performed Al-Ge eutectic bonding of MEMS devices, finding a SiO2 barrier to be necessary to avoid Si ternary formation. Kirkendall voids are observed in literature [22], [23], [24] at Ge/Si or Ge/Al to indicate diffusion at material interfaces, and these can also compromise bond strength. Diffusion barriers can prevent these processes of alloying and voiding, but the wetting of Al-Ge melt to these barriers then becomes a potential problem [24].…”