KR102451394B1 - Methods of fabricating actuator coil structure - Google Patents

Abstract

A method of manufacturing an actuator coil structure according to an embodiment of the present invention comprises: disposing a base layer on a substrate capable of transmitting light; forming a conductive micropatterned coil on the base layer; forming an insulating layer that fills the space between the micropatterned coils and covers the micropatterned coils; and lowering the adhesive force between the base layer and the substrate by irradiating light to the substrate, thereby separating the actuator coil structure including the base layer and the micropattern coil on the base layer and the insulating layer from the substrate; Including, wherein the insulating layer is a hybrid insulating layer in which different first insulating layers and second insulating layers are sequentially stacked, and the difference in the coefficient of thermal expansion between the first insulating layer and the micropatterned coil is the second insulating layer and the micropatterned coil. smaller than the difference in the coefficient of thermal expansion between them.

Description

Methods of fabricating actuator coil structure

The present invention relates to a method of manufacturing an actuator coil structure, and more particularly, to a method of manufacturing an actuator coil structure for camera auto-focus and anti-shake functions.

With the development of electronic technology, mobile devices such as smart phones and tablet computers are becoming popular. However, such a mobile device is basically equipped with a camera module that performs a camera function. As for the camera module used in a mobile device, an auto-focus camera module having an auto-focus function like a dedicated camera has been developed and widely used in order to increase the convenience of shooting. In addition, camera modules used in mobile devices are often provided with an anti-shake function like a dedicated camera in order to improve the quality of a photographed image.
Recently, there is a demand for a method for manufacturing an actuator coil structure for camera autofocus and hand-shake prevention functions that can reduce manufacturing cost while improving the quality of a photographed image.
As prior art documents disclosing the background technology of the invention, Patent Publication No. 10-2019-0013388 (20190211), Patent Publication No. 10-2017-0014792 (20170208), and Patent Publication No. 10-2017- 0097438 (20170828) and the like.

It is an object of the present invention to provide a method of manufacturing an actuator coil structure for camera autofocus and anti-shake function, which can reduce manufacturing cost while improving the quality of a photographed image. However, these problems are exemplary, and the scope of the present invention is not limited thereto.

To solve the above problems, there is provided a method of manufacturing an actuator coil structure for camera auto-focus and anti-shake function according to an aspect of the present invention.

The method of manufacturing the actuator coil structure includes disposing a base layer on a substrate capable of transmitting light; forming a conductive micropatterned coil on the base layer; forming an insulating layer that fills the space between the micropatterned coils and covers the micropatterned coils; and lowering the adhesive force between the base layer and the substrate by irradiating light to the substrate, thereby separating the actuator coil structure including the base layer and the micropattern coil on the base layer and the insulating layer from the substrate; Including, wherein the insulating layer is a hybrid insulating layer in which different first insulating layers and second insulating layers are sequentially stacked, and the difference in the coefficient of thermal expansion between the first insulating layer and the micropatterned coil is the second insulating layer and the micropatterned coil. smaller than the difference in the coefficient of thermal expansion between them.

In the method of manufacturing the actuator coil structure, the first insulating layer may be a photoresist, and the second insulating layer may be polyimide.

In the method of manufacturing the actuator coil structure, the polyimide constituting the second insulating layer may include a photosensitive polyimide.

In the method of manufacturing the actuator coil structure, the first insulating layer may be a first photoresist, and the second insulating layer may be a second photoresist.

The method of manufacturing the actuator coil structure may further include forming a via pattern on at least a portion of the micropatterned coil.

In the method of manufacturing the actuator coil structure, the via pattern may be a pattern penetrating the first insulating layer and the second insulating layer formed on at least a portion of the micropatterned coil.

In the method of manufacturing the actuator coil structure, the via pattern may be a pattern penetrating the second insulating layer formed on at least a portion of the micropatterned coil.

In the method of manufacturing the actuator coil structure, the second insulating layer includes polyimide, and the forming of the second insulating layer includes coating a mixture of PAA and a solvent and then applying heat to a first temperature to perform pre-curing. Including the first step and a second step of fully curing by heating at a second temperature higher than the first temperature, wherein the process of penetrating the second insulating layer to form a via pattern is performed after the first step and before the second step can do.

In the method of manufacturing the actuator coil structure, the height of the first insulating layer constituting the hybrid insulating layer may be higher than the height of the micropattern coil.

In the method of manufacturing the actuator coil structure, the height of the first insulating layer constituting the hybrid insulating layer may be the same as the height of the micropatterned coil.

In the method of manufacturing the actuator coil structure, the height of the first insulating layer constituting the hybrid insulating layer may be lower than the height of the micropattern coil.

According to an embodiment of the present invention made as described above, it is possible to implement a method of manufacturing an actuator coil structure for camera auto-focus and anti-shake function that can reduce manufacturing cost while improving the quality of a photographed image. Of course, the scope of the present invention is not limited by these effects.

1 is a diagram illustrating a camera module including an actuator coil for camera auto-focus and anti-shake function.
2 is a diagram illustrating an actuator coil structure for a camera auto-focus and anti-shake function according to an embodiment of the present invention.
3A to 3O are views sequentially illustrating a method of manufacturing an actuator coil structure according to an embodiment of the present invention.
4A is a diagram illustrating a connection structure of a micro-pattern coil of each layer and a via pattern connecting it vertically in the actuator coil structure according to an embodiment of the present invention.
4B is a plan view illustrating an overlapping form of a plurality of layers of micropatterned coils spaced up and down from each other shown in FIG. 4A .
5A is a diagram illustrating a connection structure of a micro-pattern coil of each layer and a via pattern connecting it up and down in the actuator coil structure according to another embodiment of the present invention.
FIG. 5B is a plan view illustrating an overlapping form of a plurality of layers of micropatterned coils spaced up and down from each other shown in FIG. 5A .
6A is a diagram illustrating a structure in which a plurality of individual coils are formed when a rectangular substrate is used, and FIG. 6B is an isolation region 45 on a rectangular substrate for separating and individualizing a plurality of coil structures arranged in an array on the rectangular substrate. 6c is a diagram illustrating a coil sheet obtained after delamination in the structure disclosed in FIG. 6a.
7A is a diagram illustrating a structure in which individual coils are formed when using a wafer substrate, and FIG. 7B is a diagram illustrating an isolation region 45 on a wafer substrate for separating and individualizing a plurality of arrayed coil structures on a wafer substrate and FIG. 7C is a diagram illustrating a coil sheet obtained after delamination in the structure disclosed in FIG. 7A.
8 is a flowchart illustrating the individualization process according to the comparative example of the present invention, and FIGS. 9A to 9E are cross-sectional views sequentially illustrating the individualization process according to the comparative example of the present invention.
10 is a flowchart illustrating the individualization process according to an embodiment of the present invention, and FIGS. 11A to 11E are cross-sectional views sequentially illustrating the individualization process according to an embodiment of the present invention.
12 is a view showing a comparison between the shape of one side of the housing and various shapes of the coil structure.
13 and 14 are photographs of structures in some stages in which the manufacturing method according to an embodiment of the present invention is actually applied.
15 is a photograph of cracks caused by a difference in thermal expansion coefficient between a plating layer pattern and a polyimide insulating layer.
16 is a flowchart illustrating a part of a method of manufacturing an actuator coil structure according to another technical idea of the present invention.
17A to 17D are views sequentially illustrating an example of a method of manufacturing an actuator coil structure according to another technical idea of the present invention.
18 is a photograph of a structure to which the manufacturing method disclosed in FIGS. 17A to 17D is applied.
19A to 19B are views sequentially illustrating another example of a method of manufacturing an actuator coil structure according to another technical idea of the present invention.
20A to 20C are views sequentially illustrating another example of a method of manufacturing an actuator coil structure according to another technical idea of the present invention.

Hereinafter, several preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Examples of the present invention are provided to more completely explain the present invention to those of ordinary skill in the art, and the following examples may be modified in various other forms, and the scope of the present invention is as follows It is not limited to an Example. Rather, these embodiments are provided so as to more fully and complete the present disclosure, and to fully convey the spirit of the present invention to those skilled in the art. In addition, in the drawings, the thickness or size of each layer is exaggerated for convenience and clarity of description.

Throughout the specification, when referring to one component, such as a film, region, or substrate, being located “on,” “connected,” “stacked,” or “coupled to,” another component, the one component It may be construed that an element may be directly “on”, “connected”, “stacked” or “coupled” to another component, or there may be other components interposed therebetween. On the other hand, when it is stated that one element is located "directly on", "directly connected to," or "directly coupled to" another element, it is construed that there are no other elements interposed therebetween. do. Like numbers refer to like elements. As used herein, the term “and/or” includes any one and any combination of one or more of those listed items.

Although the terms first, second, etc. are used herein to describe various members, parts, regions, layers and/or parts, these members, parts, regions, layers, and/or parts are limited by these terms so that they It is self-evident that These terms are used only to distinguish one member, component, region, layer or portion from another region, layer or portion. Thus, a first member, component, region, layer or portion discussed below may refer to a second member, component, region, layer or portion without departing from the teachings of the present invention.

Also, relative terms such as "above" or "above" and "below" or "below" may be used herein to describe the relationship of certain elements to other elements as illustrated in the drawings. It may be understood that relative terms are intended to include other orientations of the element in addition to the orientation depicted in the drawings. For example, if an element is turned over in the figures, elements depicted as being on the face above the other elements will have orientation on the face below the other elements. Thus, the term “top” by way of example may include both “bottom” and “top” directions depending on the particular orientation of the drawing. If the element is oriented in a different orientation (rotated 90 degrees relative to the other orientation), the relative descriptions used herein may be interpreted accordingly.

The terminology used herein is used to describe specific embodiments, not to limit the present invention. As used herein, the singular form may include the plural form unless the context clearly dictates otherwise. Also, as used herein, “comprise” and/or “comprising” refers to the presence of the recited shapes, numbers, steps, actions, members, elements, and/or groups of those specified. and does not exclude the presence or addition of one or more other shapes, numbers, movements, members, elements and/or groups.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the drawings schematically illustrating ideal embodiments of the present invention. In the drawings, variations of the illustrated shape can be envisaged, for example depending on manufacturing technology and/or tolerances. Accordingly, embodiments of the inventive concept should not be construed as limited to the specific shape of the region shown in the present specification, but should include, for example, changes in shape caused by manufacturing.

1 is a diagram illustrating a camera module including an actuator coil for camera auto-focus and anti-shake function.

Referring to FIG. 1 , the camera module 1000 includes a main board 300 on which an image device chip is mounted; a lens barrel 200 disposed on the main board 300; and a housing 400 surrounding the lens barrel 200 . An actuator coil structure 100 for camera auto-focus and anti-shake function is disposed around the lens barrel 200 . Hereinafter, an actuator coil structure and a manufacturing method thereof according to an embodiment of the present invention will be described.

2 is a diagram illustrating an actuator coil structure for a camera auto-focus and anti-shake function according to an embodiment of the present invention. (a) of Figure 2 is a plan view illustrating the overlapping form of a plurality of layers of micropatterned coils 22 spaced up and down from each other constituting the actuator coil structure 100, (b) is (a) A cross-sectional view illustrating a cross-section of the actuator coil structure 100 taken along the line A-B-B'-A' of it is do

Referring to FIG. 2 , sub-micropattern coils of, for example, four layers are disposed spaced apart from each other up and down. Of course, the four layers are exemplary cases, and may be arranged in any plurality of layers. Each sub-micropattern coil constituting the micropattern coil 22 is connected in a first direction, which is a direction selected from a clockwise direction and a counterclockwise direction, and extends, but implements the number of turns of one or more times. In Figure 2, for example, six turns are implemented. Meanwhile, the sub-micropattern coils of each layer are spaced apart from each other left and right without contact between adjacent patterns in the process of implementing a plurality of turns while extending in the first direction. Meanwhile, although not shown, a via pattern for vertically connecting sub-micropattern coils of adjacent layers is introduced. A space between the micropatterned coils 22 may be filled with an insulating layer 42 .

Specifically, the present inventors implemented the height (L1) and width (L2) of the sub micropattern coil of each layer to be about 50 μm and 25 μm, respectively, using an electroplating process, and the coil in the sub micro pattern coil of each layer The distance L3 spaced apart from side to side was realized to be about 5 μm, and the distance L4 spaced up and down between the coils in the multi-layered sub micropattern coil was realized to be about 10 μm. In measuring these numerical values, the sub micropattern coil is measured including a seed layer to be described later.

According to this configuration, a current flows into the sub micropattern coil disposed in the uppermost layer (or the lowest layer) among the micropattern coils 22 of the plurality of layers, and the current flows through the sub micropattern coil disposed in the lowest layer (or the uppermost layer) In the process, an induced magnetic field may be generated. The generated induced magnetic field may control the position of the camera lens structure disposed around the actuator coil structure 100, and by controlling the position of the camera lens structure, it is possible to perform a camera autofocus and anti-shake function.

3A to 3O are views sequentially illustrating a method of manufacturing an actuator coil structure according to an embodiment of the present invention.

3A and 3B , the substrate 10 may include a substrate transparent to light (eg, ultraviolet rays) such as glass and sapphire. A base layer 41 including polyimide is disposed on the substrate 10 . In a modified embodiment, the base layer 41 may include a photosensitive polyimide formed by mixing a polyimide precursor and a photosensitive material, or may include a photoresist. The thickness of the base layer 41 may be, for example, 5 μm to 200 μm.

Meanwhile, the UV-curable photoreactive polymer material layer 15 may be disposed on at least one surface of the base layer 41 . The UV-curable photoreactive polymer material layer 15 may be formed on at least one surface of the base layer 41 by a coating process. When the UV-curable photoreactive polymer material layer 15 is irradiated with UV light, the adhesion between the substrate 10 and the UV-curable photoreactive polymer material layer 15 is lowered, so that the substrate 10 and the base layer 41 may be separated. have.

For example, a polyimide UV tape having a UV-curable photoreactive polymer material layer applied to the surface to be adhered to the substrate may be laminated. Alternatively, after laminating the UV tape on which the UV-curable photoreactive polymer material layer is applied on both sides, the polyimide film may be continuously laminated.

Subsequently, a seed layer 21 for copper (Cu) electroplating may be formed on the polyimide base layer 41 . The seed layer 21 may be formed by a sputtering process, a vacuum deposition process, or an electroless plating process. When a sputtering process or a vacuum deposition process is applied, the seed layer 21 for copper (Cu) electroplating may include a continuous layer of Ti/Cu or a continuous layer of NiCr/Cu.

Referring to FIG. 3C , a photoresist pattern 32a is formed on the seed layer 21 . For example, the photoresist pattern 32a may have a thickness of 1 μm to 100 μm. Specifically, the photoresist pattern 32a may have a thickness of 50 μm. A space between the photoresist patterns 32a may be 1 μm to 50 μm. The width of the photoresist pattern 32a may be 1 μm to 20 μm.

Referring to FIG. 3D , a copper electroplating process is performed on the seed layer 21 to form a conductive first sub-micropattern coil 22a. Since the first sub micropattern coil 22a is formed in the empty space of the photoresist pattern 32a, the width, thickness, and separation distance of the first sub micropattern coil 22a are the separation distance and thickness of the photoresist pattern 32a. , is linked to the width. For example, the thickness of the first sub-micropattern coil 22a serving as the plating layer may be 1 μm to 100 μm. Specifically, the thickness of the first sub micropattern coil 22a may be 50 μm. On the other hand, in the cross-section, the first sub-micropattern coils 22a are shown to be spaced apart from each other on the left and right, but in reality they are integrally connected to each other while implementing a plurality of turns (eg, 15 times in FIG. 3D ). has been described previously. Meanwhile, the first electrode connection part 23a may be formed at one end of the first sub micropattern coil 22a by a copper electroplating process.

Referring to FIG. 3E , the photoresist pattern 32a is removed after the first sub micropattern coil 22a and the first electrode connection part 23a, which are plating layers, are formed.

Referring to FIG. 3F , a first seed layer pattern 21a is formed by removing a portion of the seed layer exposed between the first sub-micropattern coils 22a in the seed layer 21 . For example, a portion of the copper seed layer 21 may be removed with a copper etchant. If the width of the copper plating layer is smaller than the reference value after removing a portion of the seed layer 21, an additional plating layer may be formed on the conductive first sub-micropattern coil 22a by performing an additional electroplating process as much as the insufficient width.

Referring to FIG. 3G , a first insulating layer 42a filling the left and right spaced apart spaces of the first seed layer pattern 21a and the first sub micropattern coil 22a is formed. The insulating layer material may include photoresist or polyimide. After the insulating layer is applied, the first electrode connection part 23a may be opened using an exposure process. After forming the insulating layer, low-temperature (<180° C.) curing may be performed using ultraviolet (UV) or electron beam.

Referring to FIG. 3H , a second seed layer 21 for copper plating is formed on the first insulating layer 42a and the first electrode connection part 23a.

Referring to FIG. 3I , a second photoresist pattern 32b is formed on the second seed layer 21 . For example, the second photoresist pattern 32b may have a thickness of 1 μm to 100 μm. Specifically, the second photoresist pattern 32b may have a thickness of 50 μm. A space between the second photoresist patterns 32b may be 1 μm to 50 μm. The width of the second photoresist pattern 32b may be 1 μm to 20 μm.

Referring to FIG. 3J , a copper electroplating process is performed on the second seed layer 21 to form a conductive second sub micropattern coil 22b. Since the second sub micropattern coil 22b is formed in the empty space of the second photoresist pattern 32b, the width, thickness, and spacing of the second sub micropattern coil 22b are the same as those of the second photoresist pattern 32b. It is linked to the separation distance, thickness, and width. For example, the thickness of the second sub micropattern coil 22b serving as the plating layer may be 1 μm to 100 μm. Specifically, the thickness of the second sub micropattern coil 22b may be 50 μm. On the other hand, in the cross-section, the second sub-micropattern coils 22b are shown to be spaced apart from each other on the left and right, but in reality they are integrally connected to each other while implementing a plurality of turns (for example, 15 times in FIG. 3J). has been described previously. Meanwhile, the second electrode connection part 23b may be formed at one end of the second sub micropattern coil 22b by a copper electroplating process.

Referring to FIG. 3K , the second photoresist pattern 32b is removed after the second sub micropattern coil 22b and the second electrode connection part 23b, which are plating layers, are formed.

Referring to FIG. 3L , the second seed layer pattern 21b is formed by removing a portion of the seed layer exposed between the second sub-micropattern coils 22b in the second seed layer 21 . For example, a portion of the copper seed layer 21 may be removed with a copper etchant. If the width of the copper plating layer is smaller than the reference value after removing a part of the seed layer 21 , an additional plating layer may be formed on the conductive second sub micropattern coil 22b by performing an additional electroplating process as much as the insufficient width.

Referring to FIG. 3M , a second insulating layer 42b filling the left and right spaced apart spaces of the second seed layer pattern 21b and the second sub micropattern coil 22b is formed. The insulating layer material may include photoresist or polyimide. After the insulating layer is applied, the second electrode connection part 23b may be opened using an exposure process. After forming the insulating layer, low-temperature (<180° C.) curing may be performed using ultraviolet (UV) or electron beam.

Referring to FIG. 3N , the conductive coil 20 may be implemented by repeating the above-described process to form a seed layer and a micropatterned coil. Specifically, the seed layer is configured by sequentially arranging a first seed layer 21a, a second seed layer 21b, a third seed layer 21c, and a fourth seed layer 21d, and the micropattern coil The silver first sub micropattern coil 22a, the second sub micropattern coil 22b, the third sub micropattern coil 22c, and the fourth sub micropattern coil 22d are sequentially arranged. Meanwhile, the electrode connection part 23 is configured by sequentially arranging the first electrode connection part 23a, the second electrode connection part 23b, the third electrode connection part 23c, and the fourth electrode connection part 23d.

Each layer constituting the conductive coil 20 is electrically insulated by an insulating layer. For example, the first sub-micropatterned coil 22a of the first layer and the second seed layer 21b of the second layer are electrically insulated by an insulating layer, and the second sub-micropatterned coil 22b of the second layer is electrically insulated. ) and the third seed layer 21c of the third layer are electrically insulated with an insulating layer. Specifically, in the insulating layer 40, a base layer 41, a first insulating layer 42a, a second insulating layer 42b, a third insulating layer 42c, and a fourth insulating layer 42d are sequentially arranged. is made up of

On the other hand, each layer constituting the electrode connection portion 23 is electrically connected by contact. For example, the first electrode connection portion 23a of the first layer and the second seed layer 21b of the second layer are electrically connected to each other, and the second electrode connection portion 23b of the second layer and the third layer are electrically connected. of the third seed layer 21c is electrically connected to each other.

Referring to FIG. 3O , the substrate 10 is removed by separating it from the base layer 41 . If the substrate 10 is a substrate capable of transmitting light (eg, ultraviolet rays), and the ultraviolet curing type photoreactive polymer material layer 15 is disposed on at least one surface of the base layer 41 , the substrate 10 ) to separate the substrate 10 and the base layer 41 by irradiating light (for example, ultraviolet rays) to the UV-curable photoreactive polymer material layer 15 and the phenomenon in which the adhesion between the substrate 10 is lowered. can

However, the separation process between the substrate 10 and the base layer 41 according to the technical spirit of the present invention is not limited thereto, and other embodiments are possible. For example, the substrate 10 and the base layer 41 may be separated by irradiating a laser to the interface between the substrate 10 and the base layer 41 without introducing the UV-curable photoreactive polymer material layer 15 .

The structure shown in FIG. 3O may correspond to the left or right configuration of the actuator coil structure 100 for camera autofocus or camera shake prevention shown in FIG. 2B . The electrode connection parts 23 may be disposed at both ends. The number of stacked sub micropattern coils and the number of turns of the plurality of turns can be appropriately modified.

4A and 5A are diagrams illustrating a connection structure of a micropattern coil of each layer and a via pattern connecting it up and down in an actuator coil structure according to various embodiments of the present invention, FIGS. 4B and 5B are FIG. 4A And it is a plan view illustrating an overlapping form of a plurality of layers of micropatterned coils spaced up and down from each other as shown in FIG. 5A .

4A and 5A , the first sub-micropattern coil 22a, the second sub-micropattern coil 22b, the third sub-micropattern coil 22c, and the fourth sub-micropattern coil 22d move up and down. are spaced apart from each other, and are vertically connected by a first via pattern 22a_v, a second via pattern 22b_v, and a third via pattern 22c_v, respectively.

Specifically, the input terminal IN is disposed at the outer end of the first sub micropattern coil 22a, and the first sub micropattern connected by extending in a clockwise direction from the outer end of the first sub micropattern coil 22a. The other inner end of the coil 22a and the inner end of the second sub micropattern coil 22b are connected by the first via pattern 22a_v. Subsequently, the other end of the second sub-micropattern coil 22b and the outer end of the third sub-micropattern coil 22c are connected by extending clockwise from the inner end of the second sub-micropattern coil 22b. 2 are connected by the via pattern 22b_v. Subsequently, the other inner end of the third sub micropattern coil 22c connected by extending clockwise from the outer end of the third sub micropattern coil 22c and the inner end of the fourth sub micropattern coil 22d become the first 3 are connected by the via pattern 22c_v. Subsequently, the output terminal OUT is disposed at the other end of the fourth sub-micropattern coil 22d extending clockwise from the inner end of the fourth sub-micropattern coil 22d and connected thereto.

According to this configuration, the connection arrangement of the via pattern connecting the upper and lower adjacent sub micropattern coils has an arrangement connected from the inner side of the lower sub micro pattern coil to the inner side of the upper sub micro pattern coil, and then the lower It has an arrangement connected from the outside of the sub micropattern coil to the outside of the sub micropattern coil of the upper part, and then has an arrangement connected to the inside of the sub micropattern coil of the upper part from the inside of the sub micropattern coil of the lower part. By introducing the connection arrangement of such an alternating via pattern, it can have an advantageous advantage that the overlapping cross-sectional area of the micropatterned coils of a plurality of layers spaced apart from each other vertically can be minimized.

In addition, according to this configuration, a current flows into the input terminal IN of the first sub micropattern coil 22a disposed in the lowermost layer among the micropattern coils 22 of the plurality of layers, and the fourth sub micropattern disposed in the uppermost layer An induced magnetic field may be generated while a current flows through the output terminal OUT of the coil 22d. Since the direction in which current flows in each sub-micropattern coil is the same in the clockwise direction, the magnitude of the generated induced magnetic field is amplified. The induced magnetic field generated by amplifying the size can efficiently control the position of the camera lens structure disposed around the actuator coil structure, and by controlling the position of the camera lens structure, it is possible to perform camera autofocus and anti-shake function.

Referring to FIG. 4B , each sub micropattern coil has a repeated polygonal shape by bending the corner region R2 while being chamfered. In contrast, referring to FIG. 5B , each sub micropattern coil has a rectangular shape in which the corner region R3 is vertically bent and repeated.

First, according to the configuration shown in FIG. 4B, the cross-sectional area of the sub-micropattern coil is relatively small, so it has the advantage of easy arrangement of input terminals or output terminals, and the length of the sub-micropattern coil is relatively short, so that the electrical resistance is small. have an advantage On the other hand, according to the configuration shown in FIG. 5B, the length of the sub-micropattern coil in the longitudinal direction (parallel to the y-axis) is relatively longer, and thus the generated induced magnetic field is larger.

6A is a diagram illustrating a structure in which a plurality of individual coils are formed when a rectangular substrate is used, and FIG. 6B is an isolation region 45 on a rectangular substrate for separating and individualizing a plurality of coil structures arranged in an array on the rectangular substrate. 6c is a diagram illustrating a coil sheet obtained after delamination in the structure disclosed in FIG. 6a. This embodiment corresponds to the case where the substrate 10 is a square substrate in the method of manufacturing the actuator coil structure described with reference to FIGS. 3A to 3O . The coil sheet is made by arranging a plurality of actuator coil structures 100 as described above, and each actuator coil structure 100 obtained by individualizing them can be applied to a product. In the individualization process, the plurality of coil structures 100 and the base layer are horizontally separated from each other on the substrate 10 along the separation region 45 (shown in red in the drawing) disposed at each edge of the coil structure 100 . After this, the substrate 10 and the base layer may be separated by irradiating an ultraviolet or laser light through the rear surface of the substrate 10 .

7A is a diagram illustrating a structure in which individual coils are formed when using a wafer substrate, and FIG. 7B is a diagram illustrating an isolation region 45 on a wafer substrate for separating and individualizing a plurality of arrayed coil structures on a wafer substrate and FIG. 7C is a diagram illustrating a coil sheet obtained after delamination in the structure disclosed in FIG. 7A. This embodiment corresponds to a case in which the substrate 10 is a wafer substrate in the method of manufacturing the actuator coil structure described with reference to FIGS. 3A to 3O . The coil sheet is made by arranging a plurality of actuator coil structures 100 as described above, and each actuator coil structure 100 obtained by individualizing them can be applied to a product. In the individualization process, the plurality of coil structures 100 and the base layer are horizontally separated from each other on the substrate 10 along the separation region 45 (shown in red in the drawing) disposed at each edge of the coil structure 100 . After this, the substrate 10 and the base layer may be separated by irradiating an ultraviolet or laser light through the rear surface of the substrate 10 .

Hereinafter, a comparative example and an Example are compared and demonstrated about the above-mentioned individualization process.

8 is a flowchart illustrating the individualization process according to the comparative example of the present invention, and FIGS. 9A to 9E are cross-sectional views sequentially illustrating the individualization process according to the comparative example of the present invention.

Referring to FIGS. 8 and 9A , in the individualization process according to the comparative example of the present invention, the base layer 41 is first formed on the substrate 10 ( S10 ). Detailed descriptions of the substrate 10 and the base layer 41 are replaced with those already described with reference to other drawings. The base layer 41 may be made of polyimide (PI), photosensitive polyimide (PSPI), or photoresist. Although not shown in the drawings, the UV-curable photoreactive polymer material layer may be selectively interposed between the substrate 10 and the base layer 41 .

Referring to FIGS. 8 and 9B , a plurality of coil structures 100 arranged in an array are formed on the base layer 41 ( S20 ). Each coil structure 100 may be an actuator coil structure for the camera auto-focus and anti-shake function shown in (b) of FIG. 2 . The detailed description of the coil structure 100 is replaced with that already described with reference to other drawings ( FIGS. 2 to 7C ). At this time, the base layer 41 is provided as a single thin film integrally on the substrate 10 . On the other hand, due to the plating process applied to the process of forming the array-arranged coil structures 100 , unwanted excess plating layers 105 may be formed in empty spaces between adjacent coil structures 100 .

Referring to FIGS. 8 and 9C , the excess plating layer 105 formed in the empty space between the adjacent coil structures 100 is removed ( S30 ). The process of removing the excess plating layer 105 between the arrayed coil structures 100 may include a wet etching process. Although the excess plating layer 105 may be removed by the wet etching process, the base layer 41 is not removed.

Referring to FIGS. 8 and 9D , the base layer 41 between the arrayed coil structures 100 is removed. The process of removing the base layer 41 is implemented as a laser cutting process. The laser cutting process has a problem in that the manufacturing cost increases because expensive equipment must be used. In addition, the laser cutting process may not be suitable for realizing the light, thin, short and small coil structure 100 as a process with a precision of 5 μm or more. In addition, since the process of removing polyimide, etc. using the laser cutting process is a process of burning polyimide, etc., carbon residues remain, and there is a very high possibility of generating foreign substances and burrs. On the other hand, when the planar shape of the coil structure 100 is not a rectangle but an octagon with a tapered corner, the above problems according to the laser cutting process may appear more conspicuously.

Referring to FIGS. 8 and 9E , laser lift for separating the base layer 41 from the substrate 10 by reducing the adhesive force between the substrate 10 and the base layer 41 by irradiating a laser through the rear surface of the substrate 10 . A laser lift-off (LLO) process may be performed. Meanwhile, the base layer 41 may be separated from the substrate 10 by reducing the adhesive force between the substrate 10 and the base layer 41 by irradiating ultraviolet rays. Accordingly, the plurality of coil structures 100 may be separated from the substrate 10 while being individualized from each other.

10 is a flowchart illustrating the individualization process according to an embodiment of the present invention, and FIGS. 11A to 11E are cross-sectional views sequentially illustrating the individualization process according to an embodiment of the present invention.

Referring to FIGS. 10 and 11A , in the individualization process according to an embodiment of the present invention, the base layer 41 is first formed on the substrate 10 ( S100 ). Detailed descriptions of the substrate 10 and the base layer 41 are replaced with those already described with reference to other drawings. The base layer 41 may be made of polyimide (PI) or photosensitive polyimide (PSPI). Although not shown in the drawings, the UV-curable photoreactive polymer material layer may be selectively interposed between the substrate 10 and the base layer 41 .

Referring to FIGS. 10 and 11B , the base layer 41 may be patterned to implement a plurality of array layers spaced apart from each other instead of a single single layer ( S200 ). Accordingly, the base layer 41 may have a plurality of arrays spaced apart from each other by the isolation region 45 . Each of the separated base layers 41 may be understood as a base layer pattern. The separation region 45 may be located along the edge of each coil structure 100 implemented in a subsequent process as shown in FIG. 6B or FIG. 7B . In the embodiment of the present invention, the patterning of the base layer 41 including polyimide is implemented by a photo lithography (PHOTO LITHOGRAPHY) process rather than a laser cutting process. The photolithography process is a process with a precision of less than 1 μm, and has higher precision than the laser cutting process, and the possibility of generating a burr without generating carbon residue is relatively low. In addition, the manufacturing cost of the patterning process of the base layer 41 has the advantage that the photolithography process is significantly lower than the laser cutting process.

When the base layer 41 is made of polyimide, the base layer 41 comprising polyimide is coated with a mixture of PAA and a solvent and then subjected to a first step of pre-curing by applying heat to a first temperature, and higher than the first temperature. It can be implemented by performing a second step of heating to a high second temperature to fully cure. Polyimide can be implemented by coating a mixture of PAA (Poly (amic acid)) and a solvent and then applying heat. The process of applying heat may include a step of pre-curing to about 150° C. and a step of fully curing by heating to 250 to 350° C.

In this case, the step of forming the base layer 41 into a plurality of base layer patterns spaced apart from each other by applying a photolithography process may be performed after the first step and before the second step. When the photolithography process is performed on the fully-cured polyimide, a problem in that the patterning shape is not good may occur, but when the photolithography process is performed in a pre-cured state, the patterning shape is relatively good.

Referring to FIGS. 10 and 11C , the coil structures 100 are respectively formed on the base layers 41 spaced apart from each other and arranged in an array ( S300 ). Each coil structure 100 may be an actuator coil structure for the camera auto-focus and anti-shake function shown in (b) of FIG. 2 . A detailed description of the coil structure 100 and a method of forming the same is replaced with that already described with reference to other drawings ( FIGS. 2 to 7C ). The base layer 41 may have a height of, for example, about 15 μm, and the coil structure 100 may have a structure in which a plurality of layers each having a height of about 50 μm are stacked. Due to the plating process applied to the process of forming the array-arranged coil structures 100 , unwanted excess plating layers 105 may be formed in empty spaces between adjacent coil structures 100 . The excess plating layer 105 may be formed while filling the space between the spaced apart coil structures 100 and the space between the base layers 41 spaced apart from each other.

Referring to FIGS. 10 and 11D , the excess plating layer 105 formed in the empty space between the adjacent coil structures 100 and between the adjacent base layers 41 is removed ( S400 ). That is, the excess plating layer 105 formed on the isolation region 45 is removed. The process of removing the excess plating layer 105 may include a wet etching process. All of the excess plating layer 105 on the substrate 10 may be removed by a wet etching process.

Referring to FIGS. 10 and 11E , a laser lift that separates the base layer 41 from the substrate 10 by reducing the adhesive force between the substrate 10 and the base layer 41 by irradiating a laser through the rear surface of the substrate 10 . A laser lift-off (LLO) process may be performed. Meanwhile, the base layer 41 may be separated from the substrate 10 by reducing the adhesive force between the substrate 10 and the base layer 41 by irradiating light (eg, ultraviolet light). Accordingly, the plurality of coil structures 100 may be separated from the substrate 10 while being individualized from each other.

12 is a view showing a comparison between the shape of one side of the housing and various shapes of the coil structure.

Referring to FIG. 12 , one side of the housing 400 has an opening 405 . The housing 400 illustrated in FIG. 12 corresponds to the housing 400 illustrated in FIG. 1 . The material of the housing 400 may apply synthetic resin for weight reduction, but has a problem of low strength. In order to overcome this problem, the area of the corner region of the housing 400 is increased, so that the shape of the opening 405 may be provided in a chamfered shape rather than a perfect rectangle. On the other hand, the coil structure 100 is disposed in the opening 405 formed on the side of the housing 400, when the shape of the coil structure is provided in an approximately octagonal shape (100c) than when the shape of the coil structure is provided in a square shape (100a, 100b) The area may be larger. Since the performance of the actuator can be improved as the area of the coil structure increases, it is preferable that the cross-sectional shape of the coil structure has a structure in which corners are chamfered. In this case, since the shape of the separation region 45 described above is complicated in order to individualize the coil structure 100 , when the laser cutting process is applied as shown in FIG. 8 , the above-described problems may appear significantly. However, when a photolithography process is applied as shown in FIG. 10 , this problem can be solved.

13 and 14 are photographs of structures in some stages in which the manufacturing method according to an embodiment of the present invention is actually applied.

13 (a) is a photograph taken at 50 times magnification of a state in which the polyimide separation shape structure shown in FIG. 11b is actually implemented, and FIG. 13 (b) is a polyimide separation shape structure shown in FIG. 11b. It is a photograph taken at 100 times magnification of the actually implemented state, and FIG. 13(c) is a photograph of a state in which the plating layer formed on the separated polyimide shown in FIG. 11c is actually implemented.

14 (a) is a photograph of a state in which a plurality of coil structures are arranged in an array on a wafer substrate and a state in which some are individualized and separated, and (b) of FIG. 14 is an individualized and separated coil structure, respectively. It is a photograph taken while mounted on a circuit board, and (c) of FIG. 14 is a photograph taken of a housing in a camera module including an actuator coil for camera auto-focus and anti-shake function, FIG. 14 (d) And (e) is a photograph of a state in which the coil structure mounted on the flexible circuit board is bonded along the side of the housing. Accordingly, it can be confirmed that the coil structure is disposed in the opening formed on the side surface of the housing.

In the above-described actuator coil for camera auto-focus and anti-shake function of the present invention and a method for manufacturing the same, optimization of the plating seed layer, filling and curing of a photosensitive agent, flattening of the filling layer, exposure and plating of a high aspect ratio structure, UV film and polyimide layer Through continuous laminating coil peeling technology, etc., it is possible to improve the quality of the photographed image and reduce the manufacturing cost at the same time.

Table 1 is a table comparing the technology and quality competitiveness according to the embodiment (micro-pattern coil) and the comparative example (FP-Coil) of the present invention. The FP-Coil (Fine Pattern-Coil) method is a kind of PCB method. In the actuator coil structure for camera auto-focus and anti-shake function according to an embodiment of the present invention and a method for manufacturing the same, it is possible to improve the yield through the semiconductor and PCB fusion process compared to the comparative example, and through the use of the SMT process compared to the winding type coil The assembly yield can be improved. Furthermore, the technical idea of the present invention can be utilized for a high-efficiency charging coil for a wireless charger, a wound-type inductor, an antenna, and the like.

Compare Example
(micropattern coil) comparative example
(FP-Coil) evaluation Line Width 25㎛ 27~70㎛ - Line Space <10 μm 15~60㎛ The narrower the better Line Height 50㎛ 41㎛ - Number of Layers 2-8 2, 6 - Layer spacing <7 μm >60㎛ The narrower the better Outline Margin <50 μm >120㎛ The narrower the better Magnet-coil gap <200㎛ <150 μm the bigger the better alien substance Great Great -

Hereinafter, an actuator coil structure and a manufacturing method thereof according to another technical idea of the present invention will be described.

As described above, referring to FIG. 2 , the space between the micropattern coils 22 is filled with the insulating layer 42 , and referring to FIG. 3G , the first seed layer pattern 21a and the first sub-micro The left and right spaced apart spaces of the pattern coil 22a are filled with the first insulating layer 42a, and referring to FIG. 3M , the left and right spaced apart spaces of the second seed layer pattern 21b and the second sub micropattern coil 22b are filled with the first insulating layer 42a. The spaced space is filled with the second insulating layer 42b, and referring to FIG. 3N , each layer constituting the conductive coil 20 is electrically insulated by the insulating layer, for example, the first layer of the first layer. The sub micropatterned coil 22a and the second seed layer 21b of the second layer are electrically insulated with an insulating layer, and the second sub micropatterned coil 22b of the second layer and the third seed layer of the third layer are electrically insulated. 21c is electrically insulated with an insulating layer. Specifically, the insulating layer 40 is configured by sequentially arranging a first insulating layer 42a, a second insulating layer 42b, a third insulating layer 42c, and a fourth insulating layer 42d.

The above-described insulating layer may be made of polyimide. Polyimide can be implemented by coating a mixture of PAA (Poly (amic acid)) and a solvent and then applying heat. The process of applying heat may include a step of pre-curing to about 150° C. and a step of fully curing by heating to 250 to 350° C. In the temporary curing step, a part of the mixture is imidized, and in the complete curing step, complete imidization proceeds to form a stable polyimide.

In order to fill the above-described insulating layer including polyimide between the plating layer patterns, a process of applying heat after coating a mixture of poly (amic acid) (PAA) and a solvent between the plating layer patterns may be performed. In this case, cracks may occur due to a difference in the coefficient of thermal expansion between the plating layer pattern and the polyimide (or PAA). Furthermore, as the solvent constituting the mixture is evaporated or volatilized, the mixture may shrink (eg, decrease in volume by 30%) while forming the polyimide, resulting in cracks.

15 is a photograph of cracks caused by a difference in thermal expansion coefficient between a plating layer pattern and a polyimide insulating layer. Fig. 15 (a) is a photograph of cracks occurring after curing of polyimide when an insulating layer containing polyimide is filled between the plating layer patterns, and Fig. 15 (b) is an insulating layer containing polyimide. This is a photograph taken when bubbles are generated in the photoresist of the subsequent process due to cracks when filling between the plating layer patterns.

In order to solve this problem, the present inventor intends to provide an insulating layer filled between the plating layer patterns as a hybrid composite insulating layer composed of a first insulating layer and a second insulating layer.

According to the present invention, a method of manufacturing an actuator coil structure includes disposing a base layer on a substrate capable of transmitting light (eg, ultraviolet light); forming a conductive micropatterned coil on the base layer; forming an insulating layer covering the micropatterned coil and filling the space between the micropatterned coils; And by irradiating light (for example, ultraviolet rays) to the substrate to lower the adhesive force between the base layer and the substrate, the base layer and the actuator coil structure for camera autofocus or camera shake prevention having a micro-pattern coil on the base layer and an insulating layer on the substrate separating; Including, wherein the insulating layer is a hybrid insulating layer in which different first insulating layers and second insulating layers are sequentially stacked, and the difference in the coefficient of thermal expansion between the first insulating layer and the micropatterned coil is the second insulating layer and the micropatterned coil. It is characterized in that it is smaller than the difference in the coefficient of thermal expansion between them.

16 is a flowchart illustrating a part of a method of manufacturing an actuator coil structure according to another technical idea of the present invention.

Referring to FIG. 16 , a method of manufacturing an actuator coil structure according to another technical idea of the present invention includes forming a plating layer pattern (S1000), forming a first insulating layer filling between the plating layer patterns (S2000) and forming a second insulating layer on the first insulating layer (S3000).

Preferably, the second insulating layer is an insulating layer including polyimide, and the difference in the coefficient of thermal expansion between the first insulating layer and the plating layer is smaller than the difference in the coefficient of thermal expansion between the second insulating layer, which is polyimide, and the plating layer. By introducing such a configuration, an effect of preventing cracks generated due to a significant difference in the coefficient of thermal expansion between the insulating layer and the plating layer pattern including the polyimide during curing of the polyimide can be expected. The present inventors have confirmed that the first insulating layer can be implemented with, for example, a photoresist.

17A to 17D are views sequentially illustrating an example of a method of manufacturing an actuator coil structure according to another technical idea of the present invention.

Referring to FIG. 17A , first, a base layer 41 is formed on the substrate 10 ( S10 ). The detailed description of the substrate 10 and the base layer 41 is replaced with that previously described with reference to other drawings. The base layer 41 may be made of polyimide (PI) or photosensitive polyimide (PSPI). The photosensitive polyimide may be formed by mixing a PI precursor and a photosensitive material. Meanwhile, as a modified embodiment, the base layer 41 may be a photoresist. Although not shown in the drawings, the UV-curable photoreactive polymer material layer may be selectively interposed between the substrate 10 and the base layer 41 . A plurality of plating layer patterns 1022 spaced apart from each other are formed on the base layer 41 . The plating layer pattern 1022 may include, for example, a first seed layer pattern 21a and a first sub-micropattern coil 22a constituting the conductive coil 20 shown in FIG. 3N ; a second seed layer pattern 21b and a second sub micropattern coil 22b; a third seed layer pattern 21c and a third sub-micropattern coil 22c; and a fourth seed layer pattern 21d and a fourth sub-micropattern coil 22d; It may include at least one selected from among.

Referring to FIG. 17B , a first insulating layer 1042a may be formed between a plurality of plating layer patterns 1022 spaced apart from each other. The first insulating layer 1042a may be a negative photoresist. The negative photoresist may be formed by performing a coating step and a soft bake step.

Referring to FIG. 17C , light L is irradiated onto the first insulating layer 1042a made of negative photoresist. After irradiating light, a PEB (Post Exposure Bake) step may be performed on the negative photoresist. In the negative photoresist, cross-linking occurs in the area to which light is irradiated, so that curing occurs, and in the area to which light is not irradiated, curing does not occur and may be removed in a subsequent develop process. On the other hand, the negative photoresist is cured by additional cross-linking by heat in the PEB process. The negative photoresist may be exposed to light and may receive heat of about 100 to 120° C. during the PEB process.

Meanwhile, a region removed by a subsequent development process because light is not irradiated from the negative photoresist may be a part of the via hole 1045 in which a via pattern may be formed. The via pattern may be any one of the first via pattern 22a_v, the second via pattern 22b_v, and the third via pattern 22c_v illustrated in FIG. 5A .

Referring to FIG. 17D , a second insulating layer 1042c made of polyimide may be formed on the first insulating layer 1042a made of negative photoresist. The second insulating layer 1042c made of polyimide may be implemented by coating a mixture of poly(amic acid) (PAA) and a solvent and then applying heat. The process of applying heat may include a step of pre-curing to about 150° C. and a step of fully curing by heating to 250 to 350° C. In the provisional curing step, a part of the mixture is imidized, and in this state, a patterning process for forming the via hole 1045 may be performed. The complete curing is performed after a patterning process for forming the via hole 1045 is performed. In the complete curing step, complete imidization proceeds to form a stable polyimide.

As described above, the insulating layer 1042 filling all of the space between the plating layer patterns 1022 includes a first insulating layer 1042a that is a negative photoresist and a second insulating layer 1042c that is a polyimide. It is implemented as a hybrid composite insulating layer made of

In this case, the difference in the thermal expansion coefficient between the first insulating layer 1042a and the plating layer pattern 1022 is smaller than the difference in the thermal expansion coefficient between the second insulating layer 1042c and the plating layer pattern 1022 . By introducing such a configuration, when filling between the plating layer patterns 1022 only with the second insulating layer 1042c that is polyimide, a significant difference in the coefficient of thermal expansion between the insulating layer containing polyimide and the plating layer pattern in the process of curing the polyimide The effect of preventing the generation of cracks caused by this can be expected. In addition, in the process where a mixture of PAA (Poly (amic acid)) and a solvent is filled between the plating layer patterns 1022 and cured, the volume is contracted due to evaporation or volatilization of the solvent, which can fundamentally prevent the occurrence of empty spaces. have.

18 is a photograph of a structure to which the manufacturing method disclosed in FIGS. 17A to 17D is applied. 18A is a photograph of a structure in which a developing process is performed after irradiating light on a negative photoresist as shown in FIG. 17C, and FIG. 18B is a negative photoresist as shown in FIG. 17D. This is a photograph of a structure in which the second insulating layer 1042c made of polyimide is formed on the first insulating layer 1042a.

Referring to FIG. 18 , it can be confirmed that cracking is prevented when a hybrid composite insulating layer made of a second insulating layer 1042c made of polyimide is applied on the first insulating layer 1042a which is a negative photoresist. .

19A to 19B are views sequentially illustrating another example of a method of manufacturing an actuator coil structure according to another technical idea of the present invention.

Referring to FIG. 19A , the insulating layer 1042 filling all of the space between the plating layer patterns 1022 includes a first insulating layer 1042a made of negative photoresist and a second insulating layer 1042c made of polyimide. ) is implemented as a hybrid composite insulating layer made of In this case, the difference in the coefficient of thermal expansion between the first insulating layer 1042a and the plating layer pattern 1022 is smaller than the difference in the thermal expansion coefficient between the second insulating layer 1042c and the plating layer pattern 1022 . However, unlike FIGS. 17C to 17D , the first insulating layer 1042a , which is a negative photoresist, remains only between the plating layer patterns 1022 . In this case, the region irradiating the light L to the negative photoresist may be limited only to the region between the plating layer patterns 1022 . Preferably, the level of the first insulating layer 1042a, which is a negative photoresist, may be configured to be the same as the level of the plating layer pattern 1022 . Such a configuration may be implemented by, for example, forming the first insulating layer 1042a on the wafer substrate and then etching the entire surface.

Referring to FIG. 19B , a second insulating layer 1042c made of polyimide may be formed on the first insulating layer 1042a made of negative photoresist. The second insulating layer 1042c made of polyimide may be implemented by coating a mixture of poly(amic acid) (PAA) and a solvent and then applying heat. The process of applying heat may include a step of pre-curing to about 150° C. and a step of fully curing by heating to 250 to 350° C. In the provisional curing step, a part of the mixture is imidized, and in this state, a patterning process for forming the via hole 1045 may be performed. In the complete curing step, complete imidization proceeds to form a stable polyimide. The via hole 1045 may be filled with a conductive material in a subsequent process to be implemented as a via pattern. The via pattern may be any one of the first via pattern 22a_v, the second via pattern 22b_v, and the third via pattern 22c_v illustrated in FIG. 5A .

According to the configuration of FIGS. 19A to 19B, the height of the mixed insulating layer comprising the first insulating layer 1042a which is a negative photoresist and the second insulating layer 1042c which is a polyimide is lowered, so that the coil structure can be miniaturized. It is possible to expect an advantageous effect of increasing the size of the induced magnetic field by reducing the separation distance between the sub-micropattern coils adjacent up and down.

20A to 20C are views sequentially illustrating another example of a method of manufacturing an actuator coil structure according to another technical idea of the present invention.

Referring to FIG. 20A , first, a base layer 41 is formed on the substrate 10 ( S10 ). The detailed description of the substrate 10 and the base layer 41 is replaced with that previously described with reference to other drawings. The base layer 41 may be made of polyimide (PI) or photosensitive polyimide (PSPI). Meanwhile, as a modified example, the base layer 41 may be a photoresist. Although not shown in the drawings, the UV-curable photoreactive polymer material layer may be selectively interposed between the substrate 10 and the base layer 41 . A plurality of plating layer patterns 1022 spaced apart from each other are formed on the base layer 41 . The plating layer pattern 1022 may include, for example, a first seed layer pattern 21a and a first sub-micropattern coil 22a constituting the conductive coil 20 shown in FIG. 3N ; a second seed layer pattern 21b and a second sub micropattern coil 22b; a third seed layer pattern 21c and a third sub micropattern coil 22c; and a fourth seed layer pattern 21d and a fourth sub-micropattern coil 22d; It may include at least one selected from among.

A first insulating layer 1042b may be formed between the plurality of plating layer patterns 1022 spaced apart from each other. The first insulating layer 1042b may be a positive photoresist. A positive photoresist may be formed by performing a coating step and a soft bake step.

Referring to FIG. 20B , light L is irradiated onto the first insulating layer 1042b made of positive photoresist. After irradiating light, the positive photoresist may perform a Post Exposure Bake (PEB) step. In the positive photoresist, the constituent material is changed to acid in the region irradiated with light and removed in a subsequent develop process, and the region to which light is not irradiated remains. On the other hand, the positive photoresist is cured by cross-linking by heat in the PEB process. The positive photoresist may be exposed to light and receive heat of about 100 to 120° C. during the PEB process.

Meanwhile, a region that is irradiated with light from the positive photoresist and removed by a subsequent development process may be a part of the via hole 1045 in which a via pattern may be formed. The via pattern may be any one of the first via pattern 22a_v, the second via pattern 22b_v, and the third via pattern 22c_v illustrated in FIG. 5A .

Referring to FIG. 20C , a second insulating layer 1042c made of polyimide may be formed on the first insulating layer 1042b made of positive photoresist. The second insulating layer 1042c made of polyimide may be implemented by coating a mixture of poly(amic acid) (PAA) and a solvent and then applying heat. The process of applying heat may include a step of pre-curing to about 150° C. and a step of fully curing by heating to 250 to 350° C. In the provisional curing step, a part of the mixture is imidized, and in this state, a patterning process for forming the via hole 1045 may be performed. In the complete curing step, complete imidization proceeds to form a stable polyimide.

As described above, the insulating layer 1042 filling all of the space between the plating layer patterns 1022 includes a first insulating layer 1042b that is a positive photoresist and a second insulating layer 1042c that is a polyimide. It is implemented as a mixed insulating layer made of In this case, the difference in the coefficient of thermal expansion between the first insulating layer 1042b and the plating layer pattern 1022 is smaller than the difference in the thermal expansion coefficient between the second insulating layer 1042c and the plating layer pattern 1022 .

By introducing such a configuration, when filling between the plating layer patterns 1022 only with the second insulating layer 1042c that is polyimide, a significant difference in the coefficient of thermal expansion between the insulating layer containing polyimide and the plating layer pattern in the process of curing the polyimide The effect of preventing the generation of cracks caused by this can be expected. In addition, in the process where a mixture of PAA (Poly (amic acid)) and a solvent is filled between the plating layer patterns 1022 and cured, the volume is contracted due to evaporation or volatilization of the solvent, which can fundamentally prevent the occurrence of empty spaces. have.

In addition, various types of embodiments capable of preventing cracks from being generated due to a significant difference in the coefficient of thermal expansion between the insulating layer and the plating layer pattern are possible.

For example, the first insulating layers 1042a and 1042b constituting the hybrid composite insulating layer may be a first photoresist, and the second insulating layer 1042c may be a second photoresist. According to this, when filling between the plating layer patterns only with the insulating layer that is polyimide, cracks generated due to the significant difference in the coefficient of thermal expansion between the insulating layer containing polyimide and the plating layer pattern during curing of the polyimide can be prevented. have.

As another example, the height of the first insulating layers 1042a and 1042b constituting the hybrid composite insulating layer may be higher or the same as the height of the micropattern coil, which is the plating layer, as described above, but alternatively, it may be lower. When the height of the first insulating layers 1042a and 1042b is lower than the height of the micropatterned coil, the second insulating layer 1042c may cover the micropatterned coil while being partially filled between the micropatterned coil, which is a plating layer, and a via hole ( 1045 may be a hole passing through the second insulating layer 1042c. The first insulating layers 1042a and 1042b may be photoresist, and the second insulating layer 1042c may be polyimide or photoresist.

Although the present invention has been described with reference to the embodiment shown in the drawings, which is only exemplary, those skilled in the art will understand that various modifications and equivalent other embodiments are possible therefrom. Therefore, the true technical protection scope of the present invention should be determined by the technical spirit of the appended claims.

Claims (11)

disposing a base layer on a substrate capable of transmitting light;
forming a conductive micropatterned coil on the base layer;
forming an insulating layer that fills the space between the micropatterned coils and covers the micropatterned coils; and
separating the actuator coil structure including the base layer and the micropattern coil and the insulating layer on the base layer and the base layer from the substrate by irradiating light to the substrate to lower the adhesive force between the base layer and the substrate; including,
The insulating layer is a hybrid insulating layer in which different first insulating layers and second insulating layers are sequentially stacked,
It is characterized in that the difference in the coefficient of thermal expansion between the first insulating layer and the micropatterned coil is smaller than the difference in the coefficient of thermal expansion between the second insulating layer and the micropatterned coil,
characterized in that the first insulating layer is a photoresist and the second insulating layer is polyimide,
A method of manufacturing an actuator coil structure. delete The method of claim 1,
The polyimide constituting the second insulating layer includes a photosensitive polyimide,
A method of manufacturing an actuator coil structure. disposing a base layer on a substrate capable of transmitting light;
forming a conductive micropatterned coil on the base layer;
forming an insulating layer that fills the space between the micropatterned coils and covers the micropatterned coils; and
separating the actuator coil structure including the base layer and the micropattern coil and the insulating layer on the base layer and the base layer from the substrate by irradiating light to the substrate to lower the adhesive force between the base layer and the substrate; including,
The insulating layer is a hybrid insulating layer in which different first insulating layers and second insulating layers are sequentially stacked,
It is characterized in that the difference in the coefficient of thermal expansion between the first insulating layer and the micropatterned coil is smaller than the difference in the coefficient of thermal expansion between the second insulating layer and the micropatterned coil,
wherein the first insulating layer is a first photoresist and the second insulating layer is a second photoresist,
A method of manufacturing an actuator coil structure. The method of claim 1,
Further comprising the step of forming a via pattern on at least a portion of the micropatterned coil,
A method of manufacturing an actuator coil structure. 6. The method of claim 5,
The via pattern is a pattern passing through the first insulating layer and the second insulating layer formed on at least a part of the micropatterned coil,
A method of manufacturing an actuator coil structure. 6. The method of claim 5,
The via pattern is characterized in that it is a pattern penetrating the second insulating layer formed on at least a part of the micropatterned coil,
A method of manufacturing an actuator coil structure. 8. The method of claim 6 or 7,
The step of forming the second insulating layer is a first step of pre-curing by applying heat to a first temperature after coating a mixture of PAA and a solvent, and a second step of completely curing by heating at a second temperature higher than the first temperature. including,
The process of penetrating the second insulating layer to form a via pattern is characterized in that after the first step and before the second step,
A method of manufacturing an actuator coil structure. 5. The method of claim 1 or 4,
The height of the first insulating layer constituting the hybrid insulating layer is higher than the height of the micropatterned coil,
A method of manufacturing an actuator coil structure. 5. The method of claim 1 or 4,
The height of the first insulating layer constituting the hybrid insulating layer is the same as the height of the micropatterned coil,
A method of manufacturing an actuator coil structure. 5. The method of claim 1 or 4,
Characterized in that the height of the first insulating layer constituting the hybrid insulating layer is lower than the height of the micropatterned coil,
A method of manufacturing an actuator coil structure.

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