Micro and nanofabrication of SiGe/Ge bridges and membranes by wet-anisotropic etching

Mondiali, Valeria; Lodari, Mario; Chrastina, Daniel; Barget, Michael; Bonera, Emiliano; Bollani, Monica

doi:10.1016/j.mee.2015.03.067

Cited by 9 publications

(6 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Various Si and SiGe etching methods have been investigated during the last decade, including alkaline potassium hydroxide (KOH) and Tetramethylammonium hydroxide (TMAH: (CH 3 ) 4 N(OH)) based aqueous etchants. [2][3][4][5] KOH based chemistries showed good results in terms of Si:SiGe selectivities. 6 However, their use is problematic because of a possible degradation of CMOS devices due to alkali ions contamination.…”

mentioning

confidence: 98%

Wet Alkaline Etching of Si Selectively to SiGe for sub 10 nm Gate All Around Architectures

Rachidi

Loup

Campo

et al. 2021

ECS J. Solid State Sci. Technol.

View full text Add to dashboard Cite

Using alkaline chemistries for SiGe based Gate-All-Around architectures fabrication is still a challenge. This work reports a detailed study of Si to Si0.7Ge0.3 selective etching using NH4OH, TMAH and TEAH alkaline etchants. These alkaline solutions have all shown a great selectivity with respect to SiGe (up to 300). X-ray Photoelectron Spectroscopy and Atomic Force Microscopy have evidenced the presence of a smooth mix of SiOx + GeOx oxides during SiGe alkaline etching, which explains the obtained selectivity. When such alkaline etching processes were used on wafers with mesas etched in [Si 8 nm/Si0.7Ge0.3 8 nm] × 2 superlattices, an anisotropic behavior toward Si (111) was noticed with Scanning Electron Microscopy. Only 6 nm (or <6 nm) wide devices could be fabricated with the studied alkaline chemistries. Releasing wider SiGe nanowires required greater Si sacrificial layers’ thicknesses than √2 Critical Dimension. Finally, addition of peroxide to NH4OH alkaline chemistry reduced NH4OH anisotropy with respect to Si (111) planes, enabling the release of 10 nm wide SiGe nanowires without increasing the thickness of Si sacrificial layers.

show abstract

mentioning

confidence: 98%

Wet Alkaline Etching of Si Selectively to SiGe for sub 10 nm Gate All Around Architectures

Rachidi

Loup

Campo

et al. 2021

ECS J. Solid State Sci. Technol.

View full text Add to dashboard Cite

show abstract

“…Chemical wet etching methods can be categorized into two types: anistropic and isotropic [36,37]. Both processes have different etching rates which depend on the material properties of the sample.…”

Section: Chemical Wet Etchingmentioning

confidence: 99%

Selection of micro-fabrication techniques on stainless steel sheet for skin friction

et al. 2016

View full text Add to dashboard Cite

This review gives a concise introduction to the state-of-art techniques used for surface texturing, e.g., wet etching, plasma etching, laser surface texturing (LST), 3D printing, etc. In order to fabricate deterministic textures with the desired geometric structures and scales, the innovative texturing technologies are developed and extended. Such texturing technology is an emerging frontier with revolutionary impact in industrial and scientific fields. With the help of the latest fabrication technologies, surface textures are scaling down and more complex deterministic patterns may be fabricated with desired functions, e.g., lotus effect (hydrophobic), gecko feet (adhesive), haptic tactile, etc. The objective of this review is to explore the surface texturing technology and its contributions to the applications.

show abstract

“…Microfabrication is usually achieved by reactive ion etching [10], which requires high investment in tools and maintenance. KOH-based wet etching [11,12] has been used for microfabrication in Si at micro-and nano-scale. However, the aspect ratio of etched trenches is limited by the etching rate ratio between different crystallographic orientations and only possible in simple geometries like linear gratings or crossed linear gratings defined by the direction of <111> crystallographic planes of Si.…”

Section: Introductionmentioning

confidence: 99%

Microfabrication of X-ray Optics by Metal Assisted Chemical Etching: A Review

Romano

Stampanoni

2020

Micromachines

View full text Add to dashboard Cite

High-aspect-ratio silicon micro- and nanostructures are technologically relevant in several applications, such as microelectronics, microelectromechanical systems, sensors, thermoelectric materials, battery anodes, solar cells, photonic devices, and X-ray optics. Microfabrication is usually achieved by dry-etch with reactive ions and KOH based wet-etch, metal assisted chemical etching (MacEtch) is emerging as a new etching technique that allows huge aspect ratio for feature size in the nanoscale. To date, a specialized review of MacEtch that considers both the fundamentals and X-ray optics applications is missing in the literature. This review aims to provide a comprehensive summary including: (i) fundamental mechanism; (ii) basics and roles to perform uniform etching in direction perpendicular to the <100> Si substrate; (iii) several examples of X-ray optics fabricated by MacEtch such as line gratings, circular gratings array, Fresnel zone plates, and other X-ray lenses; (iv) materials and methods for a full fabrication of absorbing gratings and the application in X-ray grating based interferometry; and (v) future perspectives of X-ray optics fabrication. The review provides researchers and engineers with an extensive and updated understanding of the principles and applications of MacEtch as a new technology for X-ray optics fabrication.

show abstract

Micro and nanofabrication of SiGe/Ge bridges and membranes by wet-anisotropic etching

Cited by 9 publications

References 27 publications

Wet Alkaline Etching of Si Selectively to SiGe for sub 10 nm Gate All Around Architectures

Wet Alkaline Etching of Si Selectively to SiGe for sub 10 nm Gate All Around Architectures

Selection of micro-fabrication techniques on stainless steel sheet for skin friction

Microfabrication of X-ray Optics by Metal Assisted Chemical Etching: A Review

Contact Info

Product

Resources

About