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

Yu-Lin Song,Luh-Maan Chang,Manoj Kumar Reddy,Hung-Yung Wen

doi:10.3390/app12020882

Yu-Lin Song, Luh-Maan Chang + Show 2 more

Open Access

https://doi.org/10.3390/app12020882

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Journal: Applied Sciences	Publication Date: Jan 16, 2022
Citations: 3	License type: CC BY 4.0

Affiliation: National Taiwan University, Asian University

Abstract

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.

Highlights

With the evolution of the semiconductor foundry, the gate/line width of the process has been getting smaller for a higher-density integrated circuit
Electronic fine tools including scanning electron microscopy (SEM) systems, transmission electron microscopy (TEM) systems, focused ion beam (FIB) systems, and electron beam lithography (E-Beam) systems are very susceptible to extremely low-frequency (ELF) magnetic fields [3,4,5]
The results showed the evidence that a C-shaped device with a high-permeability material can collect magnetic field lines and emit them from the opening

Summary

Introduction

With the evolution of the semiconductor foundry, the gate/line width of the process has been getting smaller for a higher-density integrated circuit. Since various electrical high-power cables are used in the foundry and every electronic tool generates associated extremely low-frequency (ELF) electromagnetic fields according to its input electricity, it indispensably causes ELF electromagnetic fields generally below 300 Hz [1,2,3]. This ELF keeps the production capacity away from its original designed pattern or layouts. After installing semiconductor manufacturing equipment, the user should perform an ELF and EMF audit again to determine if the areas are still compatible with the semiconductormanufacturing equipment EMI immunity limits and that the equipment itself does not generate ELF EMFs to prevent interference with other nearby ELF-sensitive equipment. A similar shape effect can be observed in U-type barium hexaferrite-epoxy composites [30] and hollow conducting tubes [31]

Experimental and Simulation Setup

Materials

Simulation

Monitoring of Electromagnetic Fields

C Opening on Y

Conclusions