Inductor

Abstract

The invention discloses an inductor. The inductor comprises an inductance coil and a substrate structure. The substrate structure comprises a P-type semiconductor substrate, an N-type epitaxial layer and a plurality of P-type doped regions of bar-type structures, wherein the P-type doped regions are formed by adopting the photoetching and ion implantation technology. The depth of the P-type doped regions is larger than or equal to the thickness of the N-type epitaxial layer. The P-type doped regions divide the N-type epitaxial layer into a plurality of N-type doped regions to form a structure that the N-type doped regions and the P-type doped regions are alternately arranged. An exhaustion region is formed in the substrate by the N-type doped regions and the P-type doped regions which are alternately arranged to enable the substrate to be in a high resistance state so that the eddy of the substrate can be blocked. The stray capacitance of the substrate can be reduced through the exhaustion region, and quality factors of the indicator can be improved. According to the indicator, the deep groove isolation technology is not needed, and technology cost is low.

Description

technical field [0001] The invention relates to a semiconductor integrated circuit, in particular to an inductor. Background technique [0002] In semiconductor integrated circuits, such as radio frequency devices, inductors are often used, and the inductors are integrated with other semiconductor devices in the same semiconductor substrate. In the prior art, the inductor is generally formed on a semiconductor substrate, such as a silicon substrate, and is separated from the semiconductor substrate by an insulating dielectric layer. When the inductor is connected to a current, a magnetic field will be generated, and the magnetic field of the inductor will pass through the semiconductor substrate vertically, and form an eddy current on the semiconductor substrate, especially the surface of the semiconductor substrate, which is opposite to the metal current direction of the upper inductor. The eddy current will not only bring eddy current loss, but also generate an induced ma...

AI Technical Summary

Problems solved by technology

But the shortcoming of existing second kind of inductance is, because the concentration of N well 12 is much higher than P-type semiconductor substrate 11, will form extra between the N well 12 that forms on P-type semiconductor substrate 11 and inductance coil 13 The parasitic capacitance increases the parasitic capacitance between the inductance coil 13 and the P-type semiconductor substrate 11, which offsets some of the improved quality factors to a certain extent, and also reduces the resonant frequency

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