A method of increasing the surface area of ​​an inductor

Abstract

The invention discloses a method for increasing a surface area of an inductor. The method comprises the steps that a silicon wafer with a first area and a second area is provided, wherein the first area comprises a lamination layer of a first oxide layer and a second oxide layer, and the second area comprises lamination layers of the first oxide layer, a middle metal layer and the second oxide layer; strip-shaped wire lead grooves are etched in the second oxide layer of the first area when circuit wire lead holes are etched in the second area; tungsten layers are formed at the bottoms and on side walls of the strip-shaped lead wire grooves when tungsten is settled in the circuit wire lead holes; aluminum is settled after the tungsten layers are subjected to chemical-mechanical grinding, so that an aluminum layer is formed on the second oxide layer; the strip-shaped lead wire grooves are filled, so that the second oxide layer isolated by the strip-shaped lead wire grooves is connected due to the fact that the strip-shaped lead wire grooves are filled; and gaps formed by the strip-shaped lead wire grooves in the second oxide layer are not filled completely.

Description

technical field [0001] The present invention relates to the field of semiconductor manufacturing, and more particularly, the present invention relates to a method of increasing the surface area of ​​an inductor. Background technique [0002] The skin effect is also known as the "skin effect". Specifically, when an alternating electric current (AC) passes through a conductor, the current distribution on the cross-section of the conductor is uneven due to induction, and the closer to the surface of the conductor, the greater the current density; this phenomenon is called "skin effect". The skin effect increases the effective resistance of a conductor. When a current with a high frequency passes through the wire, it can be considered that the current flows only in a very thin layer on the surface of the wire, which is equivalent to the reduction of the cross-section of the wire and the increase of resistance. [0003] Skin depth means that the current density at this depth is...

AI Technical Summary

Problems solved by technology

[0005] The existing technology proposes a method called Litz winding, which can effectively improve the Q value of the inductor (especially in the case of high frequency). The existing method of realizing Litz winding is to use photolithography and etching However, limited by the lithography size and the ability of the etching process, the distance between the windings realized by this method will be larger and the density will be lower.

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