Tag: thin films

Mihaela Popovici from IMEC is visiting the ICMAB this week

Written by Anna May on February 20, 2017. Posted in Conferences, News.

Mihaela Popovici, Senior Researcher at the Semiconductor Technology and Systems Unit at IMEC (Interuniversity MicroElectronics Center, Leuven, Belgium) is visiting the ICMAB this week, invited by Anna Roig.

On Monday she gave an ICMAB Seminar at 12 pm at Sala d’actes “Carles Miravitlles”, entitled “Crystalline phase dependency of the electrical performance of oxide dielectrics for semiconductor applications”.

Short abstract:
Continuous dimensional downscaling of dielectrics and metals in semiconductor industry requires improved, non-defective metal-dielectric interfaces in order to preserve the intrinsic properties of the nanomaterials at thicknesses ranging between 5 and 10 nm. For such thin films, atomic layer deposition (ALD) is nowadays envisaged as the most suited deposition technique to deliver conformal layers in high aspect ratio structures. The crystalline phase often determines the dielectric constant and the bandgap energy and consequently electrical characteristics such as capacitance and leakage current density in metal-insulator-metal capacitors. Other specific properties like ferroelectricity seems to be driven by the presence of a particular phase (e.g. orthorhombic) with potential applications in ferroelectric field effect transistor fabrication.

Graphical Abstract from: Understanding the EOT–Jg degradation in Ru/SrTiOx/Ru metal–insulator–metal capacitors formed with Ru atomic layer deposition (Microelectronic Engineering, 147, 108-112, 2015).

Short Bio:
Mihaela Popovici is a Senior Researcher in the Semiconductor Technology and Systems Unit at IMEC, Belgium. She received her PhD in Materials Science and Engineering in 2004, at the Politehnica University of Timisoara, Romania. She had a Marie Curie fellowship at ICMAB in 2002-2003 in the field of magnetic aerogels and was post-doctoral fellow at Philips Research Eindhoven in Photonic Materials and Devices during 2005-2007. She has been working for almost a decade at the nano-electronics R&D center of IMEC in Leuven, Belgium on memory chip scaling. At present she is the technical leader of the metal-insulator-metal capacitor project for DRAM applications. Her main expertise resides in dielectric oxides and metal thin films development, physical and electrical characterization and design of complex materials stacks with applications in nano-electronic devices.

Martí Gich and Adrián Carretero on a JoVE scientific video explaining how to prepare mesoporous epitaxial quartz films on silicon substrates

Written by Anna May on October 26, 2016. Posted in New publications, News, Projects News.

Martí Gich and Adrián Carretero-Genevrier publised a scientific video on the Journal of Visualized Experiments (JoVE), a peer-reviewed scientific video journal, on December 21, 2015.

The video, entitled “Preparation of macroporous epitaxial quartz films on silicon by chemical solution deposition” (A Carretero-Genevrier, M Gich, JoVE (Journal of Visualized Experiments), e53543-e53543, 12/21/2015, Issue 106; DOI: 10.3791/53543) presents the protocol for the preparation of piezoelectric macroporous epitaxial films of quartz on silicon by soft chemistry using dip-coating and thermal treatments in air.

Abstract:

This work describes the detailed protocol for preparing piezoelectric macroporous epitaxial quartz films on silicon(100) substrates. This is a three-step process based on the preparation of a sol in a one-pot synthesis which is followed by the deposition of a gel film on Si(100) substrates by evaporation induced self-assembly using the dip-coating technique and ends with a thermal treatment of the material to induce the gel crystallization and the growth of the quartz film. The formation of a silica gel is based on the reaction of a tetraethyl orthosilicate and water, catalyzed by HCl, in ethanol.

However, the solution contains two additional components that are essential for preparing mesoporous epitaxial quartz films from these silica gels dip-coated on Si. Alkaline earth ions, like Sr²⁺ act as glass melting agents that facilitate the crystallization of silica and in combination with cetyl trimethylammonium bromide (CTAB) amphiphilic template form a phase separation responsible of the macroporosity of the films. The good matching between the quartz and silicon cell parameters is also essential in the stabilization of quartz over other SiO₂ polymorphs and is at the origin of the epitaxial growth.