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This article explores the challenges and solutions in the physical characterization of materials at the microscale using robotized systems, with a specific focus on manipulating and characterizing micrometer-sized particles with different and complex 3D shapes and internal sub-micrometer structures. In this paper, the studied particles are Molybdenum diSulfide (MoS2) based materials generated within the contact interface during friction.These particles are being studied because they offer a particularly promising solution for reducing mechanical friction and the associated high energy losses. However, they are distributed randomly within the contact area and possess intricate sub-micrometer structures. Characterization demands precise manipulation techniques in an in-situ Scanning Electron Microscope(SEM) environment. To address these challenges, existing commercial micro and nanomanipulation tools are integrated within a vacuum SEM chamber, and robotics strategies are investigated to enable the whole process from particle preparation, and manipulation setup definition, to effective MoS 2 particle characterization all in-situ SEM. A set of several complementary experimental investigations are done and involve force measurement and deformation estimation studies, leading to the first qualitative results on MoS 2 based particles directly from the friction track. The work contributes to advancements in both microscale manipulation and characterization. It also has implications for lubrication research. [ABSTRACT FROM AUTHOR]

Aluminum nitride is an excellent electrical insulator and important piezoelectric material making it suitable for a wide range of applications in electronics and optoelectronics. However, to exhibit and preserve those piezoelectric properties, care has to be taken during manufacturing process. Indeed, the c-axis crystalline orientation of AlN is a necessary condition for piezoelectricity. Therefore, the goal of this paper is to compare AlN films grown on (100) silicon substrate by pulsed reactive DC sputtering at 400 °C on top of three different metallic underlayer electrodes (Ti/Pt, Cr/Pt, and AlN/Cr/Pt) by preserving the crystalline properties not only at room temperature but also at high temperatures. Among all deposited AlN films on top of the metallic underlayer electrode, only AlN/Cr/Pt has kept its crystallinity up to 950 °C. [ABSTRACT FROM AUTHOR]

This paper reports on an original architecture of microfabricated alkali vapor cell designed for miniature atomic clocks. The cell combines diffraction gratings with anisotropically etched single-crystalline silicon sidewalls to route a normally-incident beam in a cavity oriented along the substrate plane. Gratings have been specifically designed to diffract circularly polarized light in the first order, the latter having an angle of diffraction matching the (111) sidewalls orientation. Then, the length of the cavity where light interacts with alkali atoms can be extended. We demonstrate that a longer cell allows to reduce the beam diameter, while preserving the clock performances. As the cavity depth and the beam diameter are reduced, collimation can be performed in a tighter space. This solution relaxes the constraints on the device packaging and is suitable for wafer-level assembly. Several cells have been fabricated and characterized in a clock setup using coherent population trapping spectroscopy. The measured signals exhibit null power linewidths down to 2.23 kHz and high transmission contrasts up to 17%. A high contrast-to-linewidth ratio is found at a linewidth of 4.17 kHz and a contrast of 5.2% in a 7-mm-long cell despite a beam diameter reduced to 600 μm. [ABSTRACT FROM AUTHOR]