CN-115411020-B - On-chip spiral magnetic core inductor and manufacturing method and mass production method thereof

CN115411020BCN 115411020 BCN115411020 BCN 115411020BCN-115411020-B

Abstract

The application discloses an on-chip spiral magnetic core inductor, a manufacturing method and a mass production method thereof, wherein the manufacturing method comprises the steps of forming a groove structure on a first substrate; and electrically interconnecting the groove structure and the magnetic core composite structure. The scheme of the application is that the groove structure is independently prepared on the first substrate, then the magnetic core composite structure incompatible with the CMOS technology is independently prepared, and finally the groove structure and the magnetic core composite structure on the first substrate are aligned to be electrically interconnected through the packaging technology capable of realizing mass production. Not only solves the problem of process compatibility, but also realizes the mass production of the on-chip spiral magnetic core inductor and improves the device performance.

Inventors

ZHANG TAO
WANG HAORAN
PENG CHONGMEI
CHEN CHAOHUI

Assignees

中国科学院微电子研究所

Dates

Publication Date: 20260505
Application Date: 20210526

Claims (8)

1. A method of fabricating an on-chip spiral core inductor, the method comprising: Forming a trench structure on a first substrate; Forming a magnetic core composite structure; electrically interconnecting the trench structure and the magnetic core composite structure; the method for forming the groove structure comprises the following steps: providing the first substrate, wherein the first substrate is provided with a first surface and a second surface which are opposite; Forming a patterned barrier layer on the first surface; forming a trench in the first surface based on the patterned barrier layer; forming a first metal layer on the bottom, the side edges and part of the surface of the barrier layer of the groove; Forming contact points on the surfaces of the first metal layers at two sides of the groove; The magnetic core composite structure comprises a second metal layer and a magnetic core structure arranged on the surface of the second metal layer, wherein the magnetic core structure is a single-layer film of a magnetic material layer or a multi-layer alternating composite film of the magnetic material layer and an isolation layer, and the first metal layer is electrically interconnected with the second metal layer to form the on-chip spiral magnetic core inductor.
2. The method of manufacturing of claim 1, wherein the method of forming the magnetic core composite structure comprises: providing a second substrate, the second substrate having a third surface; forming a sacrificial layer on the third surface; Forming a second metal layer on the sacrificial layer facing away from the third surface; forming a magnetic core structure on the surface of the second metal layer, which is away from the sacrificial layer; And corroding the sacrificial layer, and stripping the magnetic core structure and the second metal layer from the second substrate to form a magnetic core composite structure comprising the magnetic core structure and the second metal layer.
3. The method of claim 1, wherein the magnetic material layer is any one of a soft magnetic layer, a hard magnetic alloy layer, and an amorphous metal single layer film; The isolation layer is any one of a SiO 2 layer, an Al 2 O 3 layer, a HfO 2 layer and a TiO 2 layer.
4. The method of manufacturing according to claim 1, wherein the trench structure and the magnetic core composite structure are interconnected by thermocompression bonding; or the groove structure and the magnetic core composite structure are interconnected through laser welding; or the groove structure and the magnetic core composite structure are connected through conductive adhesive.
5. The method of manufacturing of claim 1, wherein the magnetic core composite structure is shape-matched to the trench structure such that the magnetic core composite structure is received within the trench structure.
6. An on-chip spiral core inductor prepared by the method of any one of claims 1-5, wherein the on-chip spiral core inductor comprises: a trench structure and a magnetic core composite structure electrically interconnected; the groove structure comprises a first substrate, a patterned barrier layer, a groove, a first metal layer, contact points, a first metal layer, a second metal layer, a first metal layer and a second metal layer, wherein the first substrate is provided with a first surface and a second surface which are opposite; The magnetic core composite structure comprises a second metal layer and a magnetic core structure arranged on the surface of the second metal layer, wherein the first metal layer is electrically interconnected with the second metal layer to form the on-chip spiral magnetic core inductor.
7. A mass production method of on-chip helical core inductors, the mass production method comprising: preparing a plurality of trench structures and a plurality of magnetic core composite structures by the fabrication method of claim 1; and electrically interconnecting the plurality of magnetic core composite structures and the plurality of trench structures to form a plurality of on-chip spiral magnetic core inductors.
8. The mass production method of claim 7, wherein the magnetic core composite structure and the trench structure are interconnected by thermocompression bonding or by laser welding.

Description

On-chip spiral magnetic core inductor and manufacturing method and mass production method thereof Technical Field The invention relates to the technical field of integrated circuit manufacturing and packaging, in particular to an on-chip spiral magnetic core inductor, a manufacturing method and a mass production method thereof. Background With the rapid development of communication technology, modern communication systems are increasingly in demand for integration, modularization and miniaturization. An important issue in the development of miniaturization of radio frequency circuits is how to increase the inductance density of integrated inductors. The introduction of magnetic materials is one of the important ways to increase the inductance value, but the preparation process of magnetic materials is complex, and generally requires high process temperature, and has the problem of incompatibility with CMOS process, which greatly restricts the development of on-chip inductors containing magnetic materials. The solenoid-shaped inductor has a higher quality factor, lower loss, and smaller area than the planar spiral inductors commonly used in current circuits. Solenoid-type integrated inductors containing magnetic cores, while having better performance, have limited mass production and commercialization due to complexity and incompatibility of their manufacturing processes. Disclosure of Invention In view of the above, the invention provides an on-chip spiral magnetic core inductor, a manufacturing method thereof and a batch production method thereof, which not only solve the problem of process compatibility, but also realize the batch production of the on-chip spiral magnetic core inductor and improve the device performance. In order to achieve the above purpose, the present invention provides the following technical solutions: A method of fabricating an on-chip helical core inductor, the method comprising: Forming a trench structure on a first substrate; Forming a magnetic core composite structure; And electrically interconnecting the trench structure and the magnetic core composite structure. Preferably, in the above manufacturing method, the method for forming the trench structure includes: providing the first substrate, wherein the first substrate is provided with a first surface and a second surface which are opposite; Forming a patterned barrier layer on the first surface; forming a trench in the first surface based on the patterned barrier layer; forming a first metal layer on the bottom, the side edges and part of the surface of the barrier layer of the groove; and forming contact points on the surfaces of the first metal layers at two sides of the groove. Preferably, in the above manufacturing method, the method for forming the magnetic core composite structure includes: providing a second substrate, the second substrate having a third surface; forming a sacrificial layer on the third surface; Forming a second metal layer on the sacrificial layer facing away from the third surface; forming a magnetic core structure on the surface of the second metal layer, which is away from the sacrificial layer; And corroding the sacrificial layer, and stripping the magnetic core structure and the second metal layer from the second substrate to form a magnetic core composite structure comprising the magnetic core structure and the second metal layer. Preferably, in the above manufacturing method, the magnetic core structure is a single-layer film of a magnetic material layer or a multi-layer alternating composite film of the magnetic material layer and the isolation layer. Preferably, in the above manufacturing method, the magnetic material layer is any one of a soft magnetic layer, a hard magnetic alloy layer, and an amorphous metal single-layer thin film; The isolation layer is any one of a SiO 2 layer, an Al 2O3 layer, a HfO 2 layer and a TiO 2 layer. Preferably, in the above manufacturing method, the trench structure and the magnetic core composite structure are interconnected by thermocompression bonding; or the groove structure and the magnetic core composite structure are interconnected through laser welding; or the groove structure and the magnetic core composite structure are connected through conductive adhesive. Preferably, in the above manufacturing method, the magnetic core composite structure is matched with the shape of the groove structure, so that the magnetic core composite structure is accommodated in the groove structure. The invention also provides an on-chip spiral magnetic core inductor prepared by the manufacturing method, which comprises the following steps: a trench structure and a magnetic core composite structure electrically interconnected; the groove structure comprises a first substrate, a patterned barrier layer, a groove, a first metal layer, contact points, a first metal layer, a second metal layer, a first metal layer and a second metal layer, wherein the first substrate is provid