Fabrication of SiGe/Si/Cr bent cantilevers based on self-rolling of epitaxial films

Fabrication and characterization of freestanding Si/Cr micro- and nanospirals

“…These results indicate that the scrolling direction of a Si/Cr bilayer depends on the width of the mesa stripe. It has been reported [3,4] that in a stack of SiGe/Si/Cr films, the e-beam evaporated Cr layer has tensile stress and applies a compressive stress on the Si layer. The tensile stress in the Cr layer leads to the scrolling of the Si/Cr bilayer after it has been detached from the Si substrate.…”

“…Two types of structure have been fabricated, i.e. tubes and helixes [2][3][4][5]. The diameter of these freestanding structures is related to the Young's modulus of the layers, the layers' thickness and the mismatch between the layers [2][3][4][5].…”

Fabrication and Characterization of Self-scrolling Si/Cr Micro- and Nanostructures

“…3b the same patterned bilayers start to coil from the long sides of the "finger" and form an open claw. In the latter case, a gutter-like structure can be obtained in each finger, thus preventing coiling from the front tip of the "finger" [4]. By nanorobotic manipulation, it is possible to change the micro-claw from open to closed states and vice versa.…”

“…Several different semiconductor bilayer films such as SiGe/Si and InGaAs/GaAs have been successfully used to achieve micro-/nanotubes in a controllable way. Metals and dielectrics can also be integrated into microtubes or utilized as a stressor to roll up freestanding thin films to form micro-/nanotubes [4][5][6]. It has been reported that SiGe/Si/Cr nanotubes can be fabricated from stacked films similar to how SiGe/Si bilayer nanotubes are formed, i.e.…”

Nanocrystals cylindrical microcavities exploiting thin-walled InGaAs/GaAs microtubes

“…These novel micro and nanoobjects [1][2][3][4] rely on the combination of a precise technology to control thickness and composition of grown layers such as the molecular beam epitaxy (MBE) with a wellassessed semiconductor processing technology. A wide variety of different objects in the micro and nanometer range has been fabricated and demonstrated by this technique, including tubes of different shapes, helical coils [5], rings [6], tips and bent cantilevers [7], vertical membranes [8] and mirrors [9]. Especially micro and nanotubes are suitable candidates for use in fundamental investigations as well as in a range of applications including biomedical, microfluidics, micromechanical and micro and nanophotonics fields.…”