Papers by Author: Thierry Chevolleau

Abstract: A comprehensive study on different polytypes (α-SiC and β-SiC) and crystal orientations ((0001) and (11-20) of 6H-SiC) has been investigated in order to elaborate Silicon carbide (SiC) nanopillar using inductively coupled plasma etching method. The SiC nanopillars with the cross section of rhombus, pentagon, and hexagonal have been obtained on β-SiC (001), misoriented α-SiC (11-20), and α-SiC (0001) on-axis substrates, respectively. It was found that crystal orientations and polytypes play key roles for the morphology of SiC nanopillars, which reflects the so-called Wulff's rule.

Abstract: We demonstrate a top-down fabrication technique for nanometer scale silicon carbide (SiC) pillars by using inductively coupled SF6/O2 plasma etching. The obtained SiC nanopillars exhibit high anisotropy features (aspect ratio ~ 6.5) with high etch depth (>7 μm). The etch characteristics of SiC nanopillars obtained under these conditions show a high etch rate (550 nm/min) and a high selectivity (over 60 for Ni mask). We obtained hexagonal symmetry of SiC nanopillar, which might be attributed to the crystallographic structure of the SiC phase.

Abstract: For the 45 nm interconnect technology node, porous dielectric materials (p-SiOCH) have been introduced, leading to complex integration issues due to their high sensitivity upon FC etching and ashing plasma exposure [1, 2]. Thanks to Metallic hard mask (MHM) integration high selectivities towards dielectric materials (>100:1) can be reached and minimizes exposure of p-SiOCH films to ashing plasmas. However MHM such as TiN generates other issues such as i) metal contamination in the patterned structures and ii) growth of metal based residues on the top of the hard mask [3, 4, 5]. The residues growth, which is air exposure time dependent, directly impacts the yield performance with the generation of via and line opens [.

Abstract: A top-down fabrication technique for nanometer scale silicon carbide (SiC) pillars has been demonstrated by using inductively coupled SF₆/O₂ plasma etching. At optimal etching conditions, the obtained SiC nanopillars exhibit high anisotropy features (aspect ratio ~ 6.5) with high etch depth (>7 μm). The etch characteristics of SiC nanopillars under these conditions show a high etch rate (550 nm/min) and a high selectivity (over 60 for Ni).