Strain mapping of silicon carbon suspended membranes

DOI: 10.1016/j.matdes.2021.110135

Authors: Gerard Colston (University of Warwick) , Oliver Newell (University of Warwick) , Stephen D. Rhead (University of Warwick) , Vishal A. Shah (University of Warwick) , Maksym Myronov (University of Warwick)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Materials & Design , VOL 55

State: Published (Approved)
Published: September 2021
Diamond Proposal Number(s): 11773 , 10303

Abstract: The alloy silicon carbon (Si1-yCy) has various strain engineering applications. It is often implemented as a dopant diffusion barrier and has been identified as a potential buffer layer for cubic silicon carbide (3C-SiC) heteroepitaxy. While suspended membranes formed from thin films of semiconductor (Ge and 3C-SiC) and dielectric (Si3N4) materials have been well studied, pseudomorphic, defect-free epilayers under high levels of tensile strain have received little attention. Often, tensile strain is a desired quality of semiconductors and enhancing this property can lead to various benefits of subsequent device applications. The strain state and crystalline tilt of suspended Si1-yCy epilayers have been investigated through micro-X-ray diffraction techniques. The in-plane tensile strain of the alloy was found to increase from 0.67% to 0.82%. This strain increase could reduce the C content required to achieve suitable levels of strain in such alloys and further strain enhancement could be externally induced. The source of this strain increase was found to stem from slight tilts at the edges of the membranes, however, the bulk of the suspended films remained flat. The novel process utilised to fabricate suspended Si1-yCy thin-films is applicable to many other materials that are typically not resistant to anisotropic Si wet etchants.

Journal Keywords: Silicon carbon; silicon boron; strain; membranes; MEMS

Diamond Keywords: Alloys

Subject Areas: Materials, Engineering


Instruments: B16-Test Beamline

Added On: 29/09/2021 08:14

Documents:
1-s2.0-S0264127521006900-main.pdf

Discipline Tags:

Materials Engineering & Processes Materials Science Engineering & Technology

Technical Tags:

Diffraction