Formation mechanism of nanocrystalline high-pressure phases in silicon during nanogrinding

Abstract

The phase transformations of Si under nanogrinding have been studied by transmission electron microscopy and Raman spectroscopy. Nanocrystalline high-pressure phases (Si-III/Si-XII) were found in the amorphous layer of the subsurface of heavily ground Si. The sequence of the phase transformation in nanogrinding has been found to be different to that in nanoindentation. The formation mechanism of the nanocrystalline high-pressure phases in nanogrinding is proposed based on experimental results.

Nanogrinding of soft–brittle monocrystalline mercury cadmium telluride using a ceramic bond ultrafine diamond grinding wheel

“…With a decrease of grinding heat, the plastic deformation ability decreased. It should be noted that soft-brittle material did not form amorphous layer during nanogrinding, as wellknown occurrence in hard-brittle materials, such as silicon, germanium, and gallium arsenide [14,15,22]. This was confirmed by Fig.…”

“…Nevertheless, SPDT usually generates uniform microgrooves, resulting in a decrease of surface roughness. To increase the surface roughness and efficiency of soft-brittle monocrystalline materials, nanogrinding was preliminarily employed to grind soft-brittle monocrystalline cadmium zinc telluride [13], in terms of its excellent characteristics in grinding hard-brittle first-generation silicon materials [14,15]. Whereas, little has been done on nanogrinding of monocrystalline MCT.…”

“…Resin bond was widely used for diamond grinding wheel, in terms of low cost and easy shaping [14][15][16]. Nevertheless, resin bond supported a relatively small force for holding diamond grits, resulting in a limit on a mesh size of diamond grit.…”

Novel silicon phases and nanostructures for solar energy conversion

“…The authors argued that pressure waves generated by the fspulses first amorphized regions of the sample and then induced the nucleation of R8 and BC8 NPs within these regions. Formation of nanocrystalline BC8 regions was also observed in nano-grinding experiments, 70 in SiGe epilayers, 71 and in nanoindentation experiments. [72][73][74][75] Recently, even direct colloidal synthesis of BC8 nanoparticles was reported, which would completely bypass the need for high pressure synthesis.…”

A study on the diamond grinding of ultra-thin silicon wafers

“…Studies on machine tools, diamond wheels, and grindability in Si wafer grinding have been extensively reported [4,5] and reviewed [6,7]. Previous studies demonstrated that surface and subsurface damages, including grinding marks, crystallographic defects, and highpressure induced other Si phases, were associated with the grinding process, which forms a damage layer on the top of the machined wafer [8][9][10][11][12][13][14][15][16]. It was the damage layer that induced residual stress into a wafer, and thus caused severe wafer warp or breakage when the wafer was thinned to a critical value of thickness [3,[17][18][19].…”