Induction device and method of manufacturing an induction device

Abstract

The present disclosure relates to an inductive device and a method for manufacturing the same. An inductive device may include: a first winding layer; a second winding layer disposed above and connected to the first winding layer to form a plurality of turns around a first axis; and a magnetic core disposed vertically between the first and second winding layers. The magnetic core may include a portion located entirely above the first winding layer and entirely below the second winding layer, wherein the portion may include a magnetic segment and a non-magnetic segment disposed laterally adjacent to each other along the first axis.

Description

Technical Field

[0001] The present disclosure generally relates to inductive devices, and methods of making inductive devices. Background Art

[0002] Some electrical devices include integrated voltage regulators (IVRs), such as those with a direct current-to-direct current (DC-DC) step-down (buck) converter that supplies power to a central processing unit (CPU). These IVRs typically operate in a high-frequency range and at high operating currents to provide sufficiently high current for efficient power delivery to multi-core CPUs. Therefore, IVRs often use on-board non-magnetic induction devices capable of handling such operating currents. However, these induction devices are typically bulky and occupy a large area on the board, as a large number of turns are typically required to provide a sufficiently high induction density (similar to the induction density that can be provided by magnetic induction devices). They also tend to have low induction density and a low Q factor. Currently, on-board magnetic induction devices with ferrite cores exist. However, these induction devices often exhibit high losses in the high-frequency range and quickly saturate at high operating currents. Therefore, they are typically used in DC-DC converters operating in the low-frequency range, rather than in IVRs operating in the high-frequency range. As a result, IVRs are typically large in size and exhibit issues such as high losses.

[0003] As a result, on-board non-magnetic induction devices in IVRs are being replaced by on-chip magnetic induction devices. This helps reduce the size of the IVR and improves its performance in terms of loss, induction density, and Q factor. However, when using on-chip magnetic induction devices, the problem of core saturation at high operating currents can occur. The current solution to this problem is to use larger on-chip magnetic induction devices, as these devices typically have a higher saturation current (in other words, the current at which core saturation occurs). However, such magnetic induction devices are not only larger but also have a lower induction density. This defeats the purpose of replacing on-board non-magnetic induction devices with on-chip magnetic induction devices.

[0004] Therefore, it is desirable to provide a magnetic induction device having a higher saturation current and a relatively small size. Summary of the Invention

[0005] According to various non-limiting embodiments, an induction device is provided, comprising: a first winding layer; a second winding layer arranged above the first winding layer and connected to the first winding layer to form a plurality of turns around a first axis; and a magnetic core arranged vertically between the first winding layer and the second winding layer, wherein the magnetic core may include a portion located entirely above the first winding layer and entirely below the second winding layer, and wherein the portion of the magnetic core may include magnetic segments and non-magnetic segments arranged laterally adjacent to each other along the first axis.

[0006] According to various non-limiting embodiments, a method of manufacturing an inductive device is provided. The method may include forming a first winding layer; forming a second winding layer above the first winding layer, wherein the second winding layer may be connected to the first winding layer to form a plurality of turns around a first axis; and forming a magnetic core vertically located between the first winding layer and the second winding layer, wherein the magnetic core may include a portion located entirely above the first winding layer and entirely below the second winding layer, and wherein the portion of the magnetic core may include a magnetic segment and a non-magnetic segment arranged laterally adjacent to each other along the first axis. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] In the accompanying drawings, like reference numerals generally refer to the same parts throughout the different views. Also, the drawings are not necessarily drawn to scale, with emphasis generally being placed upon illustrating the principles of the invention. Non-limiting embodiments of the present invention will now be described, for purposes of illustration only, with reference to the following drawings, in which:

[0008] Figure 1A and Figure 1B shows a simplified top view and a simplified cross-sectional view, respectively, of a sensing device according to various non-limiting embodiments;

[0009] Figures 2A to 2F Shown are examples of manufacturing according to various non-limiting embodiments. Figure 1A and 1B A simplified cross-sectional view of a method of sensing apparatus;

[0010] Figure 3 shows a simplified cross-sectional view of an induction device according to an alternative non-limiting embodiment;

[0011] Figures 4A to 4E Shown are examples of manufacturing according to various non-limiting embodiments. Figure 3 A simplified cross-sectional view of a method of sensing apparatus;

[0012] Figure 5A and Figure 5B showing a simplified top view and a simplified cross-sectional view, respectively, of a sensing device according to an alternative non-limiting embodiment;

[0013] Figure 6A and Figure 6B showing a simplified top view and a simplified cross-sectional view, respectively, of a sensing device according to an alternative non-limiting embodiment;

[0014] Figure 7 a simulated graph showing how the saturation current and inductance of an inductive device vary with changes in the magnetic core structure in the inductive device;

[0015] Figure 8 is a simulation graph showing how the saturation current and coupling coefficient of a coupled inductor vary with changes in the structure of a magnetic core in an inductive device used to form the coupled inductor; and

[0016] Figure 9 Methods of fabricating an inductive device according to various non-limiting embodiments are shown. DETAILED DESCRIPTION

[0017] Embodiments generally relate to semiconductor devices. More specifically, some embodiments relate to inductive devices. The inductive devices may be magnetic inductive devices and may be used in various applications, such as power conversion. For example, the inductive devices may be used as on-chip magnetic inductive devices for DC-DC voltage conversion and may be integrated into the far-back-end-of-line (far-BEOL) of a power management integrated circuit (PMIC), such as, but not limited to, an IVR. The inductive devices may also be used in transformers for stepping up and down voltages or for isolation.

[0018] Various aspects of the present invention and certain features, advantages and details thereof are explained more fully below with reference to the non-limiting examples shown in the accompanying drawings. Descriptions of well-known materials, manufacturing tools, processing techniques, etc. are omitted so as not to unnecessarily obscure the present invention with details. However, it should be understood that the detailed description and specific examples, while indicating aspects of the present invention, are given by way of illustration only and not by way of limitation. Various substitutions, modifications, additions and / or arrangements within the spirit and / or scope of the basic inventive concept will be apparent to those skilled in the art from this disclosure.

[0019] As used throughout the specification and claims, approximating language may be used to modify any quantitative expression that is permissible to vary without resulting in a change in the basic function to which it is related. Thus, a value modified by one or more terms such as "approximately," "about," or the like is not limited to the precise value specified. In some cases, approximate language may correspond to the precision of the instrument used to measure the value. In addition, when a direction is modified by one or more terms such as "substantially," it means that the direction applies within the normal tolerances of the semiconductor industry. For example, "substantially parallel" means extending in approximately the same direction within the normal tolerances of the semiconductor industry, while "substantially perpendicular" means an angle of ninety degrees plus or minus the normal tolerances of the semiconductor industry.

[0020] The terms used herein are for the purpose of describing specific examples only and are not intended to limit the present invention. As used herein, the singular forms "a", "an" and "the" are also intended to include the plural forms, unless the context clearly indicates otherwise. It will also be understood that the terms "comprise" (and any form of including, such as "comprises" and "comprising"), "have" (and any form of having, such as "has" and "having"), "inclue" (and any form of including, such as "includes" and "including"), and "contain" (and any form of containing, such as "contains" and "containing") are open-ended linking verbs. Thus, a method or apparatus that "comprises," "has," "includes," or "contains" one or more steps or elements has these one or more steps or elements, but is not limited to having only these one or more steps or elements. Similarly, a method step or apparatus element that "comprises," "has," "includes," or "contains" one or more features has these one or more features, but is not limited to having only these one or more features. In addition, a device or structure configured in a certain manner is configured at least in this manner, but may also be configured in ways not listed.

[0021] As used herein, when used to refer to two physical elements, the term "connected" indicates a direct connection between the two physical elements. However, the term "coupled" can indicate a direct connection or a connection through one or more intermediate elements.

[0022] As used herein, the terms "may" and "may be" indicate: the possibility of occurring under a set of circumstances; possessing a specified quality, characteristic, or function; and / or qualifying a verb by expressing one or more of the ability, function, or possibility associated with another verb. Thus, the use of "may" and "may be" indicates that the modifier is clearly suitable, permitted, or appropriate for the specified ability, function, or use, while taking into account that in certain circumstances the modifier is sometimes not suitable, permitted, or appropriate. For example, in certain circumstances, an event or ability can be expected, while in other circumstances, it cannot occur—a distinction captured by the terms "may" and "may be."

[0023] Figure 1A shows a simplified top view of a sensing device 100 according to various non-limiting embodiments, Figure 1B Shown along Figure 1A The induction device 100 is a simplified cross-sectional view of the induction device 100 taken along line AA'. The induction device 100 may be a magnetic induction device.

[0024] refer to Figure 1B The sensing device 100 may include a substrate 102. The substrate 102 may be a semiconductor substrate. For example, the substrate 102 may include a semiconductor material such as, but not limited to, silicon (Si), germanium (Ge), silicon carbide (SiC), or a combination thereof.

[0025] The sensing device 100 may further include a first insulating layer 104 disposed over the substrate 102. The first insulating layer 104 may include an insulating material, for example, a dielectric material such as, but not limited to, silicon nitride, silicon oxide, or a combination thereof.

[0026] refer to Figure 1A and 1B , the inductive device 100 may further include a first winding layer 106 disposed above the first insulating layer 104 and a second winding layer 108 disposed above the first winding layer 106. The first winding layer 106 may include a plurality of first winding segments 106a disposed laterally adjacent to each other, wherein a gap may be disposed between each pair of adjacent first winding segments 106a. Similarly, the second winding layer 108 may include a plurality of second winding segments 108a disposed laterally adjacent to each other, wherein a gap may be disposed between each pair of adjacent second winding segments 108a. To avoid cluttering the drawings, Figure 1A and 1B Only one of the first winding segments 106a and one of the second winding segments 108a are marked. Figure 1B As shown, the first winding layer 106 and the second winding layer 108 may be laterally offset from each other, and the first winding layer 106 may include an overlapping segment 106 that vertically overlaps the second winding layer 108. overlap .like Figure 1AAs shown, the inductive device 100 may further include a plurality of connectors 107 located between the first winding layer 106 and the second winding layer 108 in the vertical direction (and connecting the two) to form a plurality of turns around the first axis 150. Figure 1A Only one of the connectors 107 is labeled to avoid cluttering the drawing. Each of the first winding segment 106a, the second winding segment 108a, and the connector 107 may comprise a conductive material, such as, but not limited to, copper.

[0027] like Figure 1A and 1B As shown, the inductive device 100 may further include a magnetic core 110 vertically arranged between the first winding layer 106 and the second winding layer 108. The magnetic core 110 may include a segment 106 extending along the first axis 150 and overlapping the first winding layer 106. overlap The entire length L overlap Completely overlapping portion 110 overlap In other words, Section 110 overlap It may be located completely above the first winding layer 106 and completely below the second winding layer 108 .

[0028] The magnetic core 110 may be a segmented magnetic core. Figure 1B As shown more clearly, the portion 110 of the magnetic core 110 overlap It may include a portion 110 disposed along the first axis 150 overlap The magnetic segments at the corresponding ends (first magnetic segment 110 M1 ) and another magnetic segment (third magnetic segment 110 M3 ). The portion 110 of the magnetic core 110 overlap A second magnetic segment 110 may also be included M2 , and the first and second non-magnetic segments 110 N1 , 110 N2 The first non-magnetic segment 110 N1 The first magnetic segment 110 may be arranged laterally M1 and the second magnetic segment 110 M2 and the second non-magnetic segment 110 N2 The second magnetic segment 110 may be arranged laterally M2 and the third magnetic segment 110 M3 Located in Section 110 overlap The magnetic segments 110 at each end of M1 , 110 M3 Each of can be at least a portion of magnetic elements 1101, 1102. For example, Figure 1B As shown, the first magnetic segment 110 M1 It can be a part of the magnetic element 1101; and the third magnetic segment 110M3 The magnetic elements 1101 and 1102 may each extend laterally beyond the overlapping section 106 of the first winding layer 106. overlap (In other words, the portion 110 extending laterally beyond the core 110 overlap ).

[0029] Furthermore, if Figure 1B As shown, each magnetic segment 110 M1 , 110 M2 , 110 M3 The first axis 150 may include at least one side surface 1101a, 110a inclined at an angle relative to the first axis 150. M2 , 110b M2 , 1102a. For example, the second magnetic segment 110 M2 The first side surface 110a may include a first side surface 110a inclined in an opposite direction relative to the first axis 150 M2 and the second side surface 110b M2 (with the first side surface 110a M2 On the contrary). Therefore, the second magnetic segment 110 M2 Each of the magnetic elements 1101, 1102 may further include a first side surface 1101a, 1102a and a second side surface 1101b, 1102b (opposite to the first side surface 1101a, 1102b). Figure 1B As shown, the first side surfaces 1101a and 1102a of each magnetic element 1101 and 1102 may be tilted at an angle relative to the first axis 150 (where the side surface 1101a is tilted at an angle relative to the side surface 110a). M2 On the other hand, the second side surface 1101b, 1102b of each magnetic element 1101, 1102 may be substantially perpendicular to the first axis 150.

[0030] like Figure 1B As shown, the second magnetic segment 110 M2 Length L M2 (In other words, the maximum dimension along the axis 150 ) may be larger than the first magnetic segment 110 M1 and the third magnetic segment 110 M3 The length L of each M1 / L M3 In addition, the first magnetic segment 110 M1 , the second magnetic segment 110 M2 and the third magnetic segment 110 M3 The length L of each M1 、L M2 、L M3can be larger than the first non-magnetic segment 110 N1 and the second non-magnetic segment 110 N2 The length L of each N1 、L N2 The first and third magnetic segments 110 M1 , 110 M3 Length L M1 、L M3 The second magnetic segment 110 may be approximately equal and may each be in the range of about 100 um to about 2 mm. M2 Length L M2 The length L can be adjusted to be between about 100 μm and about 2 mm. M1 、L M2 、L M3 To change the inductive density and saturation current of the inductive device 100. In various non-limiting embodiments, the inductive device 100 can be used to form a coupled inductor. In these embodiments, the first and third magnetic segments 110 M1 , 110 M3 Length L M1 、L M3 The combination can be less than the length L overlap 20% and these magnetic segments 110 M1 , 110 M3 The first and second non-magnetic segments 110 can be arranged below the non-coupled turns to obtain an acceptable compromise between the coupling coefficient K, induction density and saturation current of the coupled inductor. N1 , 110 N2 Length L N1 、L N2 may be approximately equal and may each be in the range of about 20 um to about 40 um. N1 , 110 N2 The minimum dimension L of each of the first axis 150 is N1s 、L N2s In a non-limiting embodiment, the length L is in the range of about 10 μm to about 30 μm. N1 、L N2 Each can be about 30um and have a length L N1s 、L N2s Each may be approximately 20 μm.

[0031] Magnetic element 1101 (including first magnetic segment 110 M1 ), magnetic element 1102 (including the third magnetic segment 110 M3 ) and the second magnetic segment 110 M2Each may include materials that allow the inductive device 100 to operate in a low-loss manner in a high frequency range (e.g., the frequency range up to 100 MHz in which IVRs typically operate). M2 Each may include an amorphous soft magnetic material, such as an alloy, such as, but not limited to, cobalt zirconium tantalum (CZT) or other cobalt-based alloys. In some non-limiting embodiments, the magnetic elements 1101, 1102 and the second magnetic segment 110 may each include an amorphous soft magnetic material, such as an alloy, such as, but not limited to, cobalt zirconium tantalum (CZT) or other cobalt-based alloys. M2 Each of the first and second non-magnetic segments 110 may have a laminated structure comprising alternating layers of magnetic material and layers of non-magnetic material along a vertical axis substantially perpendicular to the first axis 150, wherein the non-magnetic material may also be an electrically insulating material. For example, the laminated structure may comprise alternating layers of amorphous soft magnetic alloy (e.g., a cobalt-based alloy) and layers of dielectric material (e.g., an oxide, such as, but not limited to, a metal oxide (e.g., cobalt oxide, aluminum oxide, silicon oxide), nitride, or a combination thereof) along the vertical axis. The first and second non-magnetic segments 110 may each have a laminated structure comprising alternating layers of magnetic material and non-magnetic material along a vertical axis substantially perpendicular to the first axis 150, wherein the non-magnetic material may also be an electrically insulating material. N1 , 110 N2 Each of the first and second non-magnetic segments 110 may include a non-magnetic material, such as a dielectric material, such as, but not limited to, photosensitive polyimide (PSPI), polyphenylene oxide (PPO), or a combination thereof. N1 , 110 N2 It may be adjacent magnetic segments 110 M1 , 110 M2 , 110 M3 The air gap between.

[0032] like Figure 1B As shown, the inductive device 100 may further include a second insulating layer 112 disposed above the first insulating layer 104. The second insulating layer 112 may include an insulating material, such as, but not limited to, PSPI. The first winding layer 106, the magnetic core 110, and the second winding layer 108 may be disposed within the second insulating layer 112. In other words, a portion of the insulating material of the second insulating layer 112 may be disposed between adjacent first winding segments 106a and adjacent second winding segments 108a. In various non-limiting embodiments, the non-magnetic segments 110 may be disposed between adjacent first winding segments 106a and adjacent second winding segments 108a. N1 , 110 N2 The non-magnetic segment 110 may have the same material composition as the second insulating layer 112. N1 , 110 N2 and the second insulating layer 112 may alternatively have different material compositions.

[0033] Figures 2A to 2F A simplified cross-sectional view illustrating a method for manufacturing an inductive device 100 according to various non-limiting embodiments is shown. Figures 2A to 2F Some reference numerals are omitted.

[0034] refer to Figure 2A , the method may include providing a substrate 102 and forming a first insulating layer 104 over the substrate 102. The method may also include forming a first winding layer 106 over the first insulating layer 104. The first winding layer 106 may be formed by any method known to those skilled in the art. For example, the first winding layer 106 may be formed by electroplating a conductive material over the first insulating layer 104, or by depositing a conductive material over the first insulating layer 104 and etching the material. A first insulating portion 202a may then be formed over the first insulating layer 104 such that the first winding layer 106 may be disposed within the first insulating portion 202a. The first insulating portion 202a may be formed by spin coating a blanket layer of insulating material over the first insulating layer 104 and curing the insulating material. Figure 2A As shown, the method may further include forming a second insulating portion 202b above the first winding layer 106, wherein the second insulating portion 202b may include a first protruding element 202b1 and a second protruding element 202b2 extending away from the first winding layer 106. These protruding elements 202b1 and 202b2 may be referred to as spacers or pillars. The second insulating portion 202b may be formed by spin-coating another insulating material layer above the first insulating portion 202a and performing photolithography and etching processes on the insulating material.

[0035] refer to Figures 2B to 2E The method may further include forming the magnetic core 110, which begins by forming a magnetic material layer 204 above the second insulating portion 202b, as shown in FIG. Figure 2B As shown. The magnetic material layer 204 can be formed by depositing a magnetic material over the second insulating portion 202b using a physical vapor deposition (PVD) process. For example, the magnetic material layer 204 can be a laminated structure that can be formed by alternately depositing a magnetic material and a non-magnetic material on the second insulating portion 202b using PVD. Figure 2B As shown, the magnetic material layer 204 may include a first protruding member 2041 and a second protruding member 2042 respectively located above the first protruding element 202b1 and the second protruding element 202b2 of the second insulating portion 202b.

[0036] like Figure 2C As shown, the method may further include forming a photoresist layer 206 over the magnetic material layer 204, wherein the photoresist layer 206 may be narrower than the magnetic material layer 204 and may include a first opening over the first protruding member 2041 and a second opening over the second protruding member 2042. Thus, the first protruding member 2041, the second protruding member 2042, and a portion at each end of the magnetic material layer 204 may be exposed.

[0037] like Figure 2D As shown, the method may include forming the magnetic core 110. This may be accomplished by patterning the magnetic material layer 204. For example, the exposed first protruding member 2041, the exposed second protruding member 2042, and the exposed portions at each end of the magnetic material layer 204 may be removed (e.g., by etching through the photoresist mask 206). Thus, the magnetic segment 110 M1 , 110 M2 , 110 M3 The non-magnetic segment 110 may be formed of a magnetic material layer 204. N1 , 110 N2 It may be formed of the first and second protruding elements 202b1 and 202b2 of the second insulating portion 202b.

[0038] like Figure 2E As shown, the method may further include forming a third insulating portion 202c over the second insulating portion 202b by, for example, spin coating an insulating material layer over the second insulating portion 202b.

[0039] like Figure 2F As shown, the method may further include forming a second winding layer 108 on the third insulating portion 202c. The second winding layer 108 may be formed by electroplating a conductive material on the third insulating portion 202c, or by depositing and etching a conductive material on the third insulating portion 202c. Figure 2F As shown, the method may include forming a fourth insulating portion 202d over the third insulating portion 202c such that the second winding layer 108 may be disposed within the fourth insulating portion 202d. The fourth insulating portion 202d may be formed by spin coating an insulating material layer over the third insulating portion 202c. Figure 2F As shown, the first, second, third and fourth insulating portions 202 a , 202 b , 202 c , 202 d may form a second insulating layer 112 .

[0040] The order of the method described above is for example only, and unless otherwise specified, the method is not limited to the order specifically described above.

[0041] Figure 3 A simplified cross-sectional view of a sensing device 300 according to an alternative non-limiting embodiment is shown. The sensing device 300 may be similar to the sensing device 100 and, therefore, common features are labeled with the same reference numerals and need not be discussed.

[0042] like Figure 3 As shown, the second magnetic segment 110 in the induction device 300 M2It may also include first and second side surfaces 110a that are inclined at an angle relative to the first axis 150. M2 , 110b M2 , but each side surface 110a M2 , 110b M2 The tilt direction of can be opposite to that in the sensing device 100. Figure 3 As shown, in the induction device 300, the magnetic core 110 may further include a portion 110 arranged along the first axis 150. overlap The magnetic segments at the corresponding ends (first magnetic segment 110 M1 ) and another magnetic segment (third magnetic segment 110 M3 ). These magnetic segments 110 M1 , 110 M3 Each of the magnetic elements 1101 and 1102 may also be part of the magnetic elements 1101 and 1102. Similar to the magnetic elements 1101 and 1102 in the sensing device 100, the first side surface 1101a and 1102a of each magnetic element 1101 and 1102 in the sensing device 300 may also be tilted at an angle relative to the first axis 150. However, the tilt direction of these side surfaces 1101a and 1102a may be opposite to the tilt direction in the sensing device 100. In addition, instead of being substantially perpendicular to the first axis 150, the second side surface 1101b and 1102b of each magnetic element 1101 and 1102 in the sensing device 300 may be tilted at an angle relative to the first axis 150. The magnetic and non-magnetic segments 1101 and 1102 may be tilted at an angle relative to the first axis 150. M1 , 110 M2 , 110 M3 , 110 N1 , 110 N2 Length L M1 、L M2 、L M3 、L N1 、L N2 、L N1s 、L N2s It may be similar to the corresponding length in the sensing device 100 .

[0043] Figures 4A to 4E A simplified cross-sectional view illustrating a method for manufacturing an inductive device 300 according to various non-limiting embodiments is shown. Figures 4A to 4E Some reference numerals are omitted.

[0044] refer to Figure 4A , the method may include a method similar to that of reference Figure 2AThe method described above provides a substrate 102, forms a first insulating layer 104 over the substrate 102, and forms a first winding layer 106. The method may also include forming a first insulating portion 402a over the first insulating layer 104, and forming a magnetic material layer 404 over the first insulating portion 402a (in other words, over the first winding layer 106). The first insulating portion 402a may be formed by spin-coating a blanket layer of insulating material over the first insulating layer 104 and curing the insulating material. Figure 2B In a similar manner to the magnetic material layer 204 described above, the magnetic material layer 404 may be formed by depositing a magnetic material over the first insulating portion 402a using a PVD process.

[0045] refer to Figure 4B The method may further include forming a photoresist layer 406 over the magnetic material layer 404. The photoresist layer 406 may be formed using a photolithography process. The photoresist layer 406 may be narrower than the magnetic material layer 404 and may include an opening. Thus, a segment of the magnetic material layer 404 may be exposed.

[0046] refer to Figure 4C The method may further include patterning the magnetic material layer 404 by removing exposed segments of the layer 404. Thus, the magnetic segments 110 of the magnetic core 110 may be formed from the magnetic material layer 404. M1 , 110 M2 , 110 M3 The patterning process can be completed by etching the magnetic material layer 404 through the photoresist mask 406. For example, a wet etching process can be used. Alternatively, if the magnetic material layer 404 is thin enough, a dry etching process can be used. Using a dry etching process can reduce the angle at which the side surfaces 1101b and 1102b are tilted relative to the first axis 150.

[0047] refer to Figure 4D The method may further include forming a second insulating portion 402b above the magnetic material layer 404 so that a portion of the second insulating portion 402b is located above the magnetic segment 110. M1 , 110 M2 , 110 M3 The non-magnetic segments 110 extend between the core 110 to form the core 110. N1 , 110 N2 The second insulating portion 402 b may be formed by spin coating an insulating material layer over the magnetic material layer 404 .

[0048] refer to Figure 4E, the method may further include forming a second winding layer 108 over the second insulating portion 402b. The second winding layer 108 may be formed by electroplating a conductive material over the second insulating portion 402b, or by depositing and etching a conductive material over the second insulating portion 402b. The method may further include forming a third insulating portion 402c over the second insulating portion 402b, such that the second winding layer 108 may be disposed within the third insulating portion 402c. The third insulating portion 402c may be formed by spin coating an insulating material layer over the second insulating portion 402b. Figure 4E As shown, the first, second, and third insulating portions 402 a , 402 b , 402 c may form a second insulating layer 112 .

[0049] The order of the method described above is for example only, and unless otherwise specified, the method is not limited to the order specifically described above.

[0050] With reference Figures 4A to 4E The described method was compared to the reference Figures 2A to 2F The described method can help reduce the amount of magnetic material layer 204 / 404 (in the Figure 2D Thus, the loss of magnetic material during the manufacturing process is reduced and the resulting magnetic core 110 may include Figure 1B The side surfaces 1101b, 1102b (with the side surfaces 1101b, 1102b substantially perpendicular to the first axis 150) Figure 3 The side surfaces 1101b and 1102b are opposite to each other and are inclined at an angle relative to the first axis 150).

[0051] Figure 5A shows a simplified top view of a sensing device 500 according to an alternative non-limiting embodiment, Figure 5B Shown along Figure 5A 1. A simplified cross-sectional view of the sensing device 500 taken along line BB' in FIG. The sensing device 500 may be similar to the sensing device 100, and thus, common features are labeled with the same reference numerals and need not be discussed further.

[0052] like Figure 5B As shown, similar to the inductive device 100, the magnetic core 110 may also include a portion 110 disposed overlap The magnetic segments at the corresponding ends (the first magnetic segment 110 M1 ) and another magnetic segment (second magnetic segment 110 M2 2). These segments 110 M1 , 110 M2 Each of the winding layers 106 may also be an overlapping segment 106 extending laterally beyond the first winding layer 106. overlap (In other words, the portion 110 extending laterally beyond the core 110overlap ) of the magnetic element 1101, 1102. In addition, each magnetic element 1101, 1102 may also have a first side surface 1101a, 1102a tilted at an angle relative to the first axis 150 and a second side surface 1101b, 1102b substantially perpendicular to the first axis 150. However, unlike the inductive device 100, in the inductive device 500, the overlapping portion 100 of the magnetic core 110 is overlap It may include only two magnetic segments (first and second magnetic segments 110 M1 , 110 M2 ) and a single non-magnetic segment 110 disposed transversely therebetween N . Non-magnetic segment 110 N The first winding layer 106 may be arranged to overlap the first winding layer 106 in the vertical direction. overlap The roughly middle part of the overlap.

[0053] like Figure 5B As shown, the first magnetic segment 110 M1 Length L M1 and the second magnetic segment 110 M2 Length L M2 can be approximately equal to and larger than the non-magnetic segment 110 N Length L N For example, the first and second magnetic segments 110 M1 , 110 M2 Length L M1 、L M2 Each may be in the range of about 100 μm to about 2 mm. Similarly, the length L M1 、L M2 It can be adjusted to change the inductive density and saturation current of the inductive device 500. When the inductive device 500 is used to form a coupled inductor, the length L M1 、L M2 The combination can be less than the length L overlap 20% and these magnetic segments 110 M1 , 110 M3 It can be arranged below the non-coupled turns to obtain an acceptable compromise between the coupling coefficient K, induction density and saturation current of the coupled inductor. N Length L N The non-magnetic segment 110 may be in the range of about 20 μm to about 40 μm. N Minimum dimension L along the first axis 150 Ns It can be in the range of about 10um to about 30um. In a non-limiting embodiment, the length L N It can be about 30um and the length L Ns It can be about 20um.

[0054] Figure 6A shows a simplified top view of a sensing device 600 according to an alternative non-limiting embodiment, Figure 6B Shown along Figure 6A 1. A simplified cross-sectional view of the sensing device 600 taken along line CC' in FIG. The sensing device 600 may be similar to the sensing device 100, and thus, common features are labeled with the same reference numerals and need not be discussed further.

[0055] like Figure 6B As shown, similar to the sensing device 100, the sensing device 600 may also include a portion 110 overlap The magnetic core 110, wherein the portion 110 overlap The first winding layer 106 extends transversely along the first axis 150 and overlaps the first winding layer 106. overlap The entire length L overlap Fully overlapped (in other words, completely above the first winding layer 106 and completely below the second winding layer 108). However, the portion 110 of the inductive device 600 overlap may include a portion 110 overlap The two non-magnetic segments (first and second non-magnetic segments 110) at the corresponding ends N1 , 110 N2 ) and a magnetic segment 110 arranged laterally between the two non-magnetic segments M .like Figure 6B As shown, the magnetic segment 110 M Length L M can be larger than the first non-magnetic segment 110 N1 Length L N1 and may also be larger than the second non-magnetic segment 110 N2 Length L N2 For example, the magnetic segment 110 M Length L M It can be in the range of about 100um to about 2mm. Similarly, the length L M It can be adjusted to change the inductive density and saturation current of the inductive device 600. When the inductive device 600 is used to form a coupled inductor, the length L M Can be less than length L overlap 20% and the magnetic segment 110 M It can be arranged below the non-coupled turns to obtain an acceptable compromise between the coupling coefficient K, induction density and saturation current of the coupled inductor. N1 Length L N1 and the second non-magnetic segment 110 N2 Length L N2The lengths L and L may be substantially equal and each be in the range of about 20 μm to about 40 μm. In a non-limiting embodiment, the length L N1 、L N2 Each of the magnetic segments 110 may be approximately 30 μm. M may include a first side surface 110a M and the second side surface 110b M , wherein these side surfaces 110a M , 110b M Both may be substantially perpendicular to the first axis 150 .

[0056] The sensing devices 500 and 600 can be used with reference to Figures 2A to 2F Similar methods as shown in the reference Figures 4A to 4E Such a manufacturing method allows the non-magnetic segment 110 in the magnetic core 110 to be formed when forming a portion of the second insulating layer 112. N1 , 110 N2 , 110 N , thereby simplifying the manufacturing process. In the resulting inductive devices 100, 300, 500, 600, the non-magnetic segment 110 N1 , 110 N2 , 110 N The second insulating layer 112 can thus have the same material composition. However, the inductive devices 100, 300, 500, 600 can be manufactured using other methods known to those skilled in the art, wherein the non-magnetic segment 110 N1 , 110 N2 , 110 N and the second insulating layer 112 may alternatively have different material compositions.

[0057] The number of magnetic segments and non-magnetic segments may be different from the number of inductive devices 100, 300, 500, 600 described above. For example, the portion 110 of the magnetic core 110 may be different from the portion 110 of the magnetic core 110. overlap Alternatively, only a single magnetic segment and a single non-magnetic segment may be included that are arranged laterally adjacent to each other along the first axis 150. In addition, the magnetic segment and the non-magnetic segment 110 M1 , 110 M2 , 110 M3 , 110 N1 , 110 N2 , 110 N The length of the magnetic segment 110 may be different from the above. For example, in the induction device 500, the magnetic segment 110 M1 , 110 M2 Length LM1 、L M2 can be different, therefore, the non-magnetic segment 110 NIt is possible not to overlap the segment 106 in the vertical direction. overlap Furthermore, the magnetic elements 1101, 1102 in the inductive devices 100, 300, 500 do not need to extend laterally beyond the overlapping section 106 of the first winding layer 106. overlap In other words, each magnetic segment (110 in the induction device 100, 300) M1 , 110 M3 and 110 of the sensing device 500 M1 , 110 M2 ) may include the entire corresponding magnetic element 1101, 1102.

[0058] As described above, in each of the inductive devices 100, 300, 500, and 600, the winding layers 106, 108 and the connectors 107 connecting the layers 106, 108 may form a plurality of turns around the first axis 150. By applying a current through the turns, a magnetic flux flow may be induced within the magnetic core 110 in a direction along the first axis 150. As described above, the magnetic core 110 may include at least one non-magnetic segment 110 disposed laterally adjacent to each other along the first axis 150. N1 , 110 N2 , 110 N and at least one magnetic segment 110 M1 , 110 M2 , 110 M3 Such a magnetic core 110 can be considered to be segmented orthogonally to the direction of magnetic flux flow. Providing such a segmented magnetic core 110 can form a high reluctance path in the magnetic core 110 and interrupt the flow of magnetic flux along the first axis 150. This can help reduce core saturation, and thus the saturation current of the inductive device 100, 300, 500, 600 can be increased (while maintaining the size of the inductive device 100, 300, 500, 600). Therefore, the inductive device 100, 300, 500, 600 can have improved current handling capability and can be used to replace existing on-board magnetic inductive devices in DC-DC converters operating in the low frequency range, as well as existing non-magnetic inductive devices in IVRs operating in the high frequency range. For example, the inductive device 100, 300, 500, 600 can be used as an on-chip magnetic inductive device in an IVR with a high operating current.

[0059] Length L of the sensing device 100, 300, 500, 600 N1 、L N2 、L N The performance of these devices 100, 300, 500, 600 can be affected. For example, increasing these lengths L N1 、L N2 、L NThe saturation current of the device 100, 300, 500, 600 may be increased, but the loss of the device 100, 300, 500, 600 may also be increased. N1 、L N2 、L N On the other hand, since the non-magnetic segment 110 N1 , 110 N2 It can be arranged at the overlapping portion 110 of the magnetic core 110 overlap At the end of the sensing device 600, the length L N1 、L N2 The etching resolution capability is not limited and can therefore be varied over a wider range.

[0060] Figure 7 1 shows a simulation graph illustrating how the saturation current Isat and the inductance Ldc of the inductive device vary with changes in the structure of the magnetic core 110 in the device. Figure 7 , point 702 corresponds to a prior art inductive device similar to devices 100, 300, 500, 600, except that the magnetic core 110 has an overlapping section 106 with the first winding layer 106. overlap The entire length L overlap Points 704, 706, and 708 correspond to sensing devices 100, 500, and 600, respectively.

[0061] like Figure 7 As shown, each of the inductive devices 100, 500, and 600 can have a lower inductance, Ldc, than a prior art device. However, each of these devices 100, 500, and 600 can have a higher saturation current, Isat, than a prior art device. Furthermore, among the inductive devices 100, 500, and 600, the inductive device 500 can have the highest saturation current (at point 706) and the inductive device 600 can have the lowest saturation current (at point 708). However, the inductive device 500 can have the lowest inductance (at point 706) and the inductive device 100 can have the highest inductance (at point 704). Therefore, the saturation current Isat and inductance, Ldc, of the inductive device can be adjusted by changing the structure of its magnetic core 110 (e.g., changing the length, number, and arrangement of the magnetic and non-magnetic segments).

[0062] The inductive devices 100 , 300 , 500 , 600 may be used to form coupled inductors. Figure 8The first simulation graph 8001 and the second simulation graph 8002 respectively show how the saturation current Isat and the coupling coefficient K of the coupled inductor change with changes in the structure of the magnetic core 110 in the inductive device used to form the coupled inductor. Figure 8 , point 802 corresponds to a point similar to that in the above reference Figure 7 The coupled inductors formed by the prior art inductive devices are depicted. Point 804 corresponds to the coupled inductor formed by inductive device 100, point 806 corresponds to the coupled inductor formed by inductive device 500, and point 808 corresponds to the coupled inductor formed by inductive device 600.

[0063] Referring to simulation curve 8001, a coupled inductor formed by a prior art device can have a lower saturation current Isat than other coupled inductors. Furthermore, among the coupled inductors formed by devices 100, 500, and 600, the coupled inductor formed by device 500 can have the highest saturation current Isat (at point 806), while the coupled inductor formed by device 100 can have the lowest saturation current Isat (at point 804). Referring to simulation curve 8002, the coupled inductors formed by inductive device 600 and the prior art device can have substantially the same coupling coefficient K (at points 802 and 808). Furthermore, the coupled inductor formed by inductive device 100 can have the highest coupling coefficient K (at point 804), while the coupled inductor formed by inductive device 500 can have the lowest coupling coefficient K (at point 806). Therefore, the trade-off between the saturation current Isat and the coupling coefficient K may be best in the coupled inductor formed by the inductive device 100 (because such a coupled inductor may have the highest coupling coefficient K of all coupled inductors, and its saturation current Isat is higher than the saturation current of the coupled inductor formed by the prior art device). Figure 8 As shown, the coupled inductor can provide an inductance in the range 8003 of about 46 nH to about 50 nH.

[0064] Figure 9 A flow chart illustrating a method of manufacturing an induction device according to various non-limiting embodiments is shown.

[0065] At 902, the method may include forming a first winding layer. The first winding layer may be, for example, the first winding layer 106 described above, and 902 may include reference Figure 2A or Figure 4A Describe the process.

[0066] At 904, the method may include forming a second winding layer above the first winding layer, wherein the second winding layer may be connected to the first winding layer to form a plurality of turns around the first axis. The second winding layer may be, for example, the second winding layer 108 described above, and 904 may include reference Figure 2F or Figure 4E Describe the process.

[0067] At 906, the method may include forming a magnetic core located vertically between the first winding layer and the second winding layer. The magnetic core may be, for example, the magnetic core 110 described above, and 906 may include reference Figures 2B to 2D or Figures 4A to 4D Describe the process.

[0068] The present invention may be embodied in other specific forms without departing from the spirit or essential characteristics of the present invention. The foregoing embodiments are therefore to be considered in all respects as illustrative rather than restrictive of the invention described herein. The scope of the present invention is therefore indicated by the appended claims rather than by the foregoing description, and all changes that come within the meaning and range of equivalents of the claims are intended to be embraced therein.

Claims

1. A sensing device comprising: first winding layer; a second winding layer disposed above and connected to the first winding layer to form a plurality of turns around a first axis; as well as a magnetic core arranged between the first winding layer and the second winding layer in a vertical direction, wherein the magnetic core includes a portion located completely above the first winding layer and completely below the second winding layer; The portion of the magnetic core includes a magnetic segment and a non-magnetic segment arranged laterally adjacent to each other along the first axis, wherein the magnetic segment includes at least one side surface inclined at an angle relative to the first axis.

2. The inductive device of claim 1 , wherein the magnetic segment is a first magnetic segment and the portion of the magnetic core further comprises a second magnetic segment; and The non-magnetic segment is laterally arranged between the first magnetic segment and the second magnetic segment. 3 . The induction device according to claim 2 , wherein the length of the first magnetic segment is equal to the length of the second magnetic segment.

4. The induction device according to claim 2, wherein the first winding layer includes an overlapping section that overlaps with the second winding layer in a vertical direction; and the non-magnetic section is arranged to overlap with a middle portion of the overlapping section of the first winding layer in the vertical direction.

5. The induction device of claim 2, wherein a length of each of the first magnetic segment and the second magnetic segment is greater than a length of the non-magnetic segment.

6. The inductive device of claim 2, wherein the non-magnetic segment is a first non-magnetic segment, and wherein the portion of the magnetic core further comprises a third magnetic segment and a second non-magnetic segment disposed laterally between the second magnetic segment and the third magnetic segment. 7 . The induction device of claim 6 , wherein a length of the second magnetic segment is greater than a length of each of the first magnetic segment and the third magnetic segment.

8. The induction device of claim 6, wherein a length of each of the first magnetic segment, the second magnetic segment, and the third magnetic segment is greater than a length of each of the first non-magnetic segment and the second non-magnetic segment.

9. The inductive device of claim 1 , wherein the non-magnetic segment is a first non-magnetic segment and the portion of the magnetic core further comprises a second non-magnetic segment; and The magnetic segment is laterally arranged between the first non-magnetic segment and the second non-magnetic segment.

10. The inductive device of claim 9, wherein the length of the magnetic segment is greater than the length of each of the first and second non-magnetic segments.

11. The inductive device of claim 1 , wherein the portion of the magnetic core comprises a further magnetic segment, and wherein the magnetic segment and the further magnetic segment are arranged at respective ends of the portion of the magnetic core along the first axis.

12. The inductive device of claim 11, wherein each of the magnetic segment and the further magnetic segment comprises a portion of a magnetic element that extends laterally beyond the portion of the magnetic core.

13. The induction device of claim 11 , wherein each of the magnetic segment and the further magnetic segment comprises at least a portion of a magnetic element comprising a first side surface and a second side surface opposite the first side surface; The first side surface is inclined at an angle relative to the first axis and the second side surface is perpendicular to the first axis.

14. The induction device of claim 11 , wherein each of the magnetic segment and the further magnetic segment comprises at least a portion of a magnetic element comprising a first side surface and a second side surface opposite the first side surface; Each of the first side surface and the second side surface is inclined at an angle relative to the first axis.

15. The inductive device according to claim 1, wherein the inductive device further comprises an insulating layer, wherein the first winding layer, the second winding layer, and the magnetic core are arranged within the insulating layer; and The non-magnetic segment and the insulating layer of the portion of the magnetic core comprise the same material composition.

16. A method of manufacturing an induction device, the method comprising: forming a first winding layer; forming a second winding layer over the first winding layer, wherein the second winding layer is connected to the first winding layer to form a plurality of turns around a first axis; as well as forming a magnetic core vertically located between the first winding layer and the second winding layer, wherein the magnetic core includes a portion located entirely above the first winding layer and entirely below the second winding layer; The portion of the magnetic core includes a magnetic segment and a non-magnetic segment arranged laterally adjacent to each other along the first axis, wherein the magnetic segment includes at least one side surface inclined at an angle relative to the first axis.

17. The method of claim 16, further comprising forming an insulating portion over the first winding layer, wherein the insulating portion comprises a protruding element extending away from the first winding layer; as well as The forming of the magnetic core comprises: forming a magnetic material layer over the insulating portion; forming the magnetic segments of the magnetic core from the layers of magnetic material; and The non-magnetic section of the magnetic core is formed from the protruding element of the insulating portion.

18. The method of claim 17, wherein the layer of magnetic material includes a protruding member located above the protruding element of the insulating portion.

19. The method of claim 16, wherein forming the magnetic core comprises: forming a magnetic material layer above the first winding layer; forming the magnetic segments of the magnetic core from the layers of magnetic material; as well as An insulating portion is formed over the layer of magnetic material such that a portion of the insulating portion forms the nonmagnetic segment of the magnetic core.

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