Coupled inductor and the method to make the same

Abstract

A coupled inductor has two coils made by film or a lithography processes, wherein a first coil is disposed on a top surface of a magnetic sheet and a second coil is disposed on the bottom surface of the magnetic sheet, for controlling the variations of the alignments of the two coils in a smaller range.

Description

CROSS-REFERENCES TO RELATED APPLICATION[0001]The present application claims the benefit of U.S. Provisional Application Ser. No. 63 / 180,659 filed on Apr. 28, 2021, which is hereby incorporated by reference herein and made a part of the specification.BACKGROUND OF THE INVENTIONI. Field of the Invention[0002]The present invention relates to a coupled inductor, and in particular, to a coupled inductor made by a film or a lithography process.II. Description of Related Art[0003]A conventional coupled inductor uses two coils made of discrete conductive wires, wherein each coil is wound on a corresponding pillar in a vertical direction. However, the variations of the position alignment of the two coils can vary in a larger range for the coupled inductors, which will affect the reliability and performance of the coupled inductors.[0004]Furthermore, the conventional coupled inductor uses the first mold, as shown in FIG. 1A, and the second mold, as shown in FIG. 1B, wherein a first coil C1 is...

AI Technical Summary

Benefits of technology

The present invention provides a way to make two coils that are connected to each other. These coils can be made through a process called lithography, and they can be aligned very precisely to have a better and more reliable connection. The invention also allows for the creation of multiple coupled inductors all in one process, which can help to control variations in the alignment between the two coils. This results in a more consistent and reliable connection between the two coils, even in large production runs.

Problems solved by technology

However, the variations of the position alignment of the two coils can vary in a larger range for the coupled inductors, which will affect the reliability and performance of the coupled inductors.

In addition, each conventional coupled inductor is made separately, so the deviation of the center of the column is a Gaussian Distribution, which is a big variation range and not good for maintaining the reliability and performance of the products.

Furthermore, as shown in FIG. 1C and FIG. 1D, the gap between the upper coil C2 and the lower coil C1 can vary in a big range such as 0-76 um, which is also not good for maintaining the reliability and performance of the products.

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