Single-ended inductor

Abstract

The invention discloses a single-ended inductor. A metal coil of the single-ended inductor is of a planar spiral winding structure, the metal width of the metal coil gradually increases from the inner circle to the outer circle. Under high frequency, the skin depth of all positions near the inner circle is smaller than the skin depth of the outer circle, so that after the metal width near the inner circle is reduced, the resistance in all positions near the inner circle will not increase, and current of the metal coil will not be lowered. Meanwhile, after the metal width near the inner circle is reduced, effective average distance between every two adjacent metal wire sections of the metal coil is reduced, the mutual inductance between every two adjacent metal wire sections of the metal coil increases, and therefore the inductance of the single-ended inductor can be improved.

Description

technical field [0001] The present invention relates to a semiconductor integrated circuit, in particular to a single-ended inductor. Background technique [0002] In semiconductor integrated circuits, such as radio frequency devices, inductors are often used, which are integrated with other semiconductor devices in the same semiconductor substrate. In the prior art, the inductance in the radio frequency device generally adopts a plane spiral inductance, the metal coil of the inductance has a plane spiral surrounding structure, and the metal coil of the whole inductance is fabricated in the same metal layer. Single-ended inductance is a half-integer or integer-turn planar spiral inductance, such as figure 1 As shown, it is a schematic diagram of the metal coil of the existing single-ended inductor; the metal coil of the existing single-ended inductor is in a plane spiral surrounding structure. From the inner ring 11 to the outer ring 12 of the metal coil, the metal width of...

AI Technical Summary

Problems solved by technology

But in this way, the overlapping capacitive reactance between the metals will be increased, and the resonant frequency will be lowered, which will deteriorate the quality factor (Q value) of the inductor.

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