Mitigation of Electro Magnetic Interference by Using C-Shaped Composite Cylindrical Device

The extremely low-frequency (ELF) and its corresponding electromagnetic field influences the yield of CMOS processes in the foundry, especially for high-end equipment such as scanning electron microscopy (SEM) systems, transmission electron microscopy (TEM) systems, focused ion beam (FIB) systems, and electron beam lithography (E-Beam) systems. There are several techniques to mitigate electromagnetic interference (EMI), among which active shielding systems and passive shielding methods are widely used. An active shielding system is used to generate an internal electromagnetic field to reduce the detected external electromagnetic field in electric coils with the help of the current. Although the active shielding system reduces the EMI impact, it induces an internal electromagnetic field that could affect the function of nearby tools and/or high-performance probes. Therefore, in this study, we have used a C-shaped cylindrical device combined with an active shielding system and passive shielding techniques to reduce EMI for online monitoring and to overcome the aforementioned issues. In this study, the active shielding system was wrapped with a permalloy composite material (i.e., a composite of nickel and iron alloy) as a tubular device. A C-shaped opening was made on the tubular structure vertically or horizontally to guide the propagation of the electromagnetic field. This C-shaped cylindrical device further reduced electromagnetic noise up to −5.06 dB and redirected the electromagnetic field toward the opening direction on the cylindrical device. The results demonstrated a practical reduction of the electromagnetic field.

Intrinsic noise reduction of a Gamma-ray Backscattering imaging device

In order to increase the contrast and to improve the imaging capabilities of a Gamma-ray Backscattering device some changes are proposed with the aim of achieving a reduction of the intrinsic noise of the device. Simulated results suggest that the shielding system proposed, in addition to the use of a 68 Ge -γ ray source, produce a considerable reduction of the intrinsic noise of the device.

Development of the Vacuum Arc Chute for a 110 kV Single-Break Vacuum Circuit Breaker

Requirements for high-voltage vacuum circuit breakers for networks with a grounded neutral, which are stemming from the prospects of using vacuum circuit breakers in networks with the solidly grounded neutral are formulated. The arch chute design for a 110 kV single-break vacuum circuit breaker that takes into account the occurrence of repeated breakdowns is developed. The shielding system equalizes the voltage over the chute casing, decreases the electric field intensity at the “triple point”, protects the casing dielectric from becoming dusted with metallic contact parts erosion products, prevents the occurrence of cascade breakdown between the contact parts and central shield, and eliminates a possible decrease of the chute electric strength as it gradually works out its switching life. It is shown that the chute design includes measures to prevent the possibility of repeated breakdowns during disconnection up to class С1 according to GOST 52565-2006. It has been proven that for vacuum arc chutes for class С2 (for switching a capacitive load) it is necessary to develop a chute with two breaks between the contact parts or to connect two vacuum chutes in series. The shielding system adopted in the chute rules out the possibility of ceramic casing to become metallized, which decreases the chute electric strength as it gradually works out its switching life, and the vacuum arc transfer to beyond the inter-contact gap boundaries onto the central shield, the burnout of which results in that the vacuum arc chute loses its tightness and fully loses its functional properties.