Murata (France)

With the high integration of microelectronic devices, nanoscale surface characterization is critical to process development. The widely used atomic force microscopy provides 2D characterization of the surface at the nanoscale. In this paper, a statistical study of the topographic mode PeakForce Tapping mode is performed. A silicon calibration sample with structures of 20 nm, is characterized, and from 28 days of measurements at the same location, data processing and analysis is proposed to determine the reproducibility of the height measured by AFM. From the section analysis, an uncertainty of 0.26 nm in air is determined. Statistical analysis is also used, and the mode is applied to characterize a dielectric material on the top of a highly integrated capacitor.

In this work, nanometric (6–21 nm thick) amorphous TiO2 films have been elaborated and characterized in liquid- and solid-state electrolyte (LiPON) half-cell architectures. For all considered configurations, the volumetric capacity extracted from cyclic voltammetry and galvanostatic cycling within the 0.5–3 V potential range almost corresponds to the theoretical value expected for the LixTiO2 (x ∼ 1) phase at low current density. Interestingly, TiO2 films after LiPON deposition exhibited a thickness-independent constant initial amount of intercalated lithium ions and did not require a first activation process, in comparison to the liquid electrolyte configuration. Furthermore, the cooperative effects of high Li+ intercalation kinetics and low interfacial charge transfer resistance for a 6 nm TiO2 electrode led to an outstanding surface capacity of 0.7 μAh cm–2 at 1 μA cm–2 and high rate performance with 60% capacity holding ratio at 1 mA cm–2, thus highlighting the extrinsic pseudocapacitive behavior of our sub-10 nm TiO2 electrodes. A LixTiO2 6 nm/LiPON 100 nm/Pt hybrid micro-supercapacitor has been successfully fabricated, achieving an operating voltage window of 3 V and a surface capacitance of 94 μF cm–2 at 50 mV s–1. In addition, the device also exhibited 97% coulombic efficiency upon cycling for 10,000 continuous charge–discharge cycles. This work proposes an approach that allows us to adjust the Li-ion storage properties of TiO2 by nanoengineering and gives insights into the electrochemical performance enhancement by taking advantage of the pseudocapacitance-assisted lithium storage mechanism.

The work presented here is driven by the motivation to design and manufacture a LiDAR module generating a short pulse with high output LD (Laser Diode) power peak. As will be demonstrated in this paper, this was made possible by the use of high voltage Si-IPD (Silicon Integrated Passive Device) with embedded trench capacitors as a mechanical holder and offering amazing interconnection flexibility to optimize the placement of the different module components. Compared to classical PCB based solutions, the Si-IPD made it possible the realization of low parasitic inductance by optimizing the current distribution paths between the switching devices, the passive components and the 3D assembly of the module. Noise and surge reduction along with efficiency improvement of the power electronics system is observed.

In the race of miniaturization, manufacturers of automotive devices always require smaller electronic components. To save space and in the same time improve performances, some sensors are placed directly ‘Under the hood’ and are directly exposed to harsh environment, such as braking systems, oil, exhaust gaz, cooling liquids and so on. These requirements drive the increasing demand for reliable capacitors that can withstand temperatures up to 200°C. Murata has developed a unique capacitor technology in silicon as well as integrated passive devices based on 3D trenches with high aspect ratio. This paper reports the reliability of automotive grade silicon capacitors for high temperature applications up to 200°C. The development of a range of Silicon capacitors, with an operating temperature from -55°C up to +200°C will be presented here. The manufacturing process optimizations and the design rules (Design for Reliability) implemented to prevent failure mechanisms when exposed to such a high temperature will be described. The solutions to avoid top to bottom metal short (TBMS), electromigration (EM), intermetallic compound formation (IMC) and to enhance time-dependent dielectric breakdown (TDDB) will be depicted. The products have been qualified according to automotive electronic standard AEC-Q100, but exceeding by 65°C the grade 0, which is defined as the most severe conditions of the standard. The results of the reliability qualification both at wafer level and product level will be presented in details. The long-term stability of key electrical parameters of the Silicon capacitors is a main differentiator versus standard capacitor technologies for the ‘under the hood’ automotive market.

In this study, we demonstrate the capability to detect microscopic stable displacement nature created by proton irradiations with a method based on the discrimination of the three major low frequency noise sources generally observed in semiconductor devices. Low frequency noise measurements are carried out in silicon in-situ phosphorus doped polycrystalline silicon serpentine resistance used as test vehicle. We observe that for the pristine sample, the voltage noise power density can be explained only considering 1/f and thermal noise contribution on the total noise, while for irradiated sample generation recombination noise prevails. Preliminary results on low frequency noise spectroscopy, used as a diagnostic tool in order to identify stable traps created by protons irradiations are presented.

Deformed osseous structures have been reported as rare causes of extracranial internal carotid artery (ICA) dissection, including the styloid process and the hyoid bone. Here, the authors describe the first known case of symptomatic ICA dissection caused by a giant osteophyte due to atlantoaxial osteoarthritis. The left ICA was fixed at the skull base and at the ICA portion compressed by the osteophyte, and it was highly stretched and injured between the two portions during neck rotation. The patient was successfully treated with ligation of the affected ICA following balloon test occlusion. Atlantoaxial osteoarthritis should be considered in the differential diagnosis of ICA dissection in patients with a severely deformed cervical spine.

〔目的〕本研究では，言語教示によって対象者の能動的注意を自己の身体内部および外部に向けさせて，運動を認識している際の脳活動の違いを明らかにすることを目的とした。〔対象〕右利き健常成人8名とした。〔方法〕機能的近赤外分光装置（fNIRS）を用いて検証した。〔結果〕能動的注意を右手で自己の身体内部へ向けた場合では，右半球前頭前野と右頭頂領域で，左手で身体外部へ向けた場合では，左半球前頭前野と左頭頂領域で酸素化ヘモグロビンの有意な増加を認めた。〔結語〕今回の結果から，運動を認識する際の運動と同側大脳半球の左右大脳半球の機能分化として，能動的注意が右手で身体内部に向かう場合は右半球前頭－頭頂領域が，左手で身体外部に向かう場合は左半球前頭－頭頂領域が担うといった側性化が存在することが示唆された。