KR102092637B1 - Manufacturing Method Of 3D Shape Force Touch - Google Patents

Abstract

The present invention relates to a method for manufacturing a pressure touch sensor (Force Touch, FT), and more specifically, by forming an electrode directly on a base substrate having a three-dimensional shape including a curved portion rather than a flat surface, cost reduction and thickness reduction can be achieved. It relates to a three-dimensional shape pressure touch sensor manufacturing method.

Description

Manufacturing method of 3D shape pressure touch sensor {Manufacturing Method Of 3D Shape Force Touch}

* The present invention relates to a method for manufacturing a pressure touch sensor (Force Touch, FT), more specifically, by forming an electrode directly on a base substrate having a three-dimensional shape, not a flat surface, but a curved portion, as well as cost reduction and thickness reduction. It relates to a three-dimensional shape pressure touch sensor manufacturing method that can be.

With the development of touch screen technology, a keypad having an input means is replaced with a touch panel, and a display device integrally coupled to the panel is widely used in smart devices.

Accordingly, various touch interface technologies have emerged, and a display device in which a pressure touch sensor (Force Touch), which is a pressure sensor that senses a pressure at a touch position as well as a touch, has been developed.

The pressure touch sensor refers to a three-dimensional (3D) touch technology that implements various functions by providing different feedback according to the position or strength of the screen of the display to be touched.

The conventional pressure touch sensor is manufactured by combining a sensor electrode body having an elastic body coupled between two electrodes on a base substrate formed of a plastic material.

However, as described above, the manufacturing method of the pressure touch sensor has a problem in that the thickness is thick because the base substrate and the sensor electrode body are laminated, it is difficult to apply to a shape having a curved surface rather than a flat surface, and the manufacturing cost increases. There was a problem.

That is, in order to manufacture the curved pressure touch sensor in the conventional method, a separate sensor electrode body having a pattern is manufactured, and the sensor electrode body must be attached to a base substrate made of glass or plastic through an adhesive such as a double-sided tape. Therefore, there is a problem in that it is difficult to manufacture the sensor electrode body by combining it with a curved surface rather than a flat surface, and thus there is a problem of reduced productivity and yield.

In addition, since the sensor electrode body is deformed into a curved shape, the reliability and durability of the sensor electrode body are deteriorated due to the bonding of the sensor electrode body with the curved base substrate.

The object of the present invention as derived to solve the above problems is to form an electrode directly on a base substrate having a three-dimensional shape including a curved portion, rather than a plane, to reduce the cost and to reduce the thickness of the three-dimensional shape pressure. It is to provide a method for manufacturing a touch sensor.

To achieve the above object, a method of manufacturing a three-dimensional shape pressure touch sensor according to the present invention comprises the steps of manufacturing a base electrode substrate by directly forming a first electrode using laser and plating on the base substrate; And laminating the base electrode substrate and the second electrode substrate on which the elastic body is formed.

The manufacturing of the base electrode substrate includes applying a laser pigment on a base substrate having a three-dimensional shape to form a laser pigment layer, and one electrode according to a pattern path program designed on the base substrate on which the laser pigment layer is formed. And forming a first electrode pattern by irradiating a laser in response to the pattern, and forming a base electrode substrate by forming a first electrode by adhering a conductive material to the first electrode pattern through electroplating. It is characterized by.

The three-dimensional shape includes an irregular three-dimensional shape, such as a free-form curve or a mixture of a curved line and a straight line, as well as a regular three-dimensional shape such as a hemispherical shape and an ellipse based on the elevation; The base substrate having the three-dimensional shape is characterized by being manufactured in a three-dimensional shape suitable for design purposes by injection of synthetic resin material.

The pattern path program converts a first electrode pattern designed in a planar form into a corrected first electrode pattern that is modified to fit a curved surface of a three-dimensional shape, wherein the corrected first electrode pattern is a curved electrode pattern formed at regular intervals on the curved surface. It is characterized by being converted to conform to 3D shape characteristics by projecting in a plane.

In addition, the pattern path program designs a first electrode pattern as a 3D curved electrode pattern, specifies a location of a specific area to be patterned in the designed 3D curved electrode pattern, and considers the specific area coordinates and the irradiation direction of the laser device. It is characterized in that it is possible to form an accurate electrode pattern for a 3D curved surface by controlling the laser device so that the laser is irradiated only in the specific area in synchronization with laser coordinates.

In the step of irradiating the laser to form a first electrode pattern, surface modification of the alignment mark region is performed simultaneously so that the laser is irradiated with the laser to accurately align the first electrode pattern region while laminating with the second electrode substrate. And, the step of forming the base electrode substrate is characterized in that a conductive material is fixed to the first electrode pattern through electroplating to simultaneously form the first electrode and the alignment mark.

The method of manufacturing a 3D shape pressure touch sensor according to the present invention can minimize defects in a conventional laminating process by forming electrodes directly on a base substrate having a 3D shape including a curved portion rather than a flat surface, and the manufacturing process is simple. It has an excellent effect that can reduce costs.

In addition, since the thickness is as thin as the thickness of the first electrode substrate, an excellent effect that can reduce the thickness of the device occurs.

1 schematically shows a three-dimensional shape pressure touch sensor according to a preferred embodiment of the present invention,
2 and 3 is a process diagram schematically showing a three-dimensional shape pressure touch sensor manufacturing method according to an embodiment of the present invention,
4 is a flowchart schematically showing a manufacturing method according to the process diagrams of FIGS. 2 and 3.
5 schematically shows a pattern path program correction according to the present invention.
6 schematically shows a process of generating an alignment mark according to the present invention.

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

Basically, the pressure touch sensor is a device that senses pressure information of how hard it is pressed, not just the touch. It can press any part of the track pad through a structure that arranges an elastic body that acts as a spring. Even if is pressed, all of the elastic bodies are pressed and the amount of pressing varies depending on the position. Each electrode sensor recognizes the changed capacity in the elastic body, which acts as a force sensor, and comprehensively senses the signal to determine which position is pressed. It works, and it works on the principle that it can sense even the pressing force.

The pressure touch sensor basically consists of two electrode layers, measures the change in the capacitance value between the formed electrodes, and measures the applied force using the principle that the capacitance value increases when a force is applied to the two electrodes to cause a distance change. do.

1 schematically shows a 3D shape pressure touch sensor according to a preferred embodiment of the present invention, and FIGS. 2 and 3 schematically show a method of manufacturing a 3D shape pressure touch sensor according to a preferred embodiment of the present invention 4 is a flowchart schematically showing a manufacturing method according to the process diagrams of FIGS. 2 and 3.

1 to 4, the pressure touch sensor according to the present invention is not a structure in which a sensor electrode body in which an elastic body is coupled between a base substrate and two electrode substrates is coupled, but an elastic body after the first electrode is directly formed on the base substrate. It is formed in a structure in which the second electrode substrate is formed.

That is, the method for manufacturing a pressure touch sensor according to the present invention comprises the steps of manufacturing the base electrode substrate 10 on which the first electrode 130 is formed on the base substrate 110 and the second electrode substrate 20 on which the elastic body 210 is formed. ).

Here, the first electrode and the second electrode are terms used to relatively distinguish the two electrodes, and it is obvious that they do not mean absolute positions of the electrodes, such as upper and lower.

First, to prepare the base electrode substrate 10, a base substrate 110 having a three-dimensional shape is prepared.

The base substrate 110 may be formed of a synthetic resin material such as PC, PET, PMMA, and the like, and is manufactured in a geometric shape with free bending to have a three-dimensional shape.

Here, the three-dimensional shape is defined as a concept including all shapes including irregular three-dimensional shapes, such as a free-form curve or a mixture of a curved line and a straight line, as well as a regular three-dimensional shape such as a hemispherical shape and an ellipse based on the elevation. .

Since the base substrate 110 is manufactured in an injection form, it can be manufactured in various three-dimensional shapes according to design purposes.

The method of directly forming the first electrode on the base substrate is a first method of forming a surface by reforming the surface by irradiating a laser to the surface of the base substrate injection-molded with a thermoplastic resin and a laser pigment on the base substrate of injection molding. A second method of forming a surface by coating a laser pigment on a laser pigment after coating, and then forming it, and a third method of forming a part other than electrode formation by dry etching by depositing or depositing a conductive material on the injection-produced base substrate. It can be divided into.

Hereinafter, the first method will be described in order.

First, the first method is to prepare and prepare a three-dimensionally shaped base substrate 110 formed of a thermoplastic resin by injection (a in FIG. 2), and irradiate a laser in response to a one electrode pattern designed on the base substrate. Forming a first electrode pattern (b in FIG. 2), and forming a conductive electrode pattern through electroplating on the first electrode pattern (c in FIG. 2), where the first electrode is formed. The electrode substrate is completed.

More specifically, since the base substrate is formed of a thermoplastic resin and the thermoplastic resin is activated in response to a laser, surface modification through laser irradiation is possible.

The laser is irradiated only on the electrode pattern region 111 on the surface of the base substrate 110 formed of the thermoplastic resin to form a large amount of fine pores at a constant density on the surface to modify the surface.

The step of forming the first electrode pattern irradiates a laser to an area corresponding to the first electrode pattern according to a pre-designed pattern path program on the base substrate 110 and performs surface modification only on the area corresponding to the first electrode pattern. do.

The laser moves along a pattern path, and repeatedly moves a certain section depending on the shape and thickness of the pattern, or may be irradiated along a certain path.

Here, the base substrate according to the present invention has a flat surface in a curved shape of a geometric shape rather than a flat shape, and an electrode is formed on the curved surface, and since the laser moves in a straight shape, the laser according to the first electrode pattern designed in a flat shape If irradiated, an error may occur in the process of forming the first electrode pattern.

For example, in the case of a base plate having a hemispherical shape, if the electrode pattern is designed in a flat shape, the spacing on the plane is designed to be constant, but in the case of a curved surface, the gap between arcs must be constant depending on the angle from the center of the curved surface rather than on the plane. Due to this, when the laser is irradiated while moving only in the linear direction, the area of the electrode pattern is widened from the center to the end.

Therefore, the pattern path program requires a step of converting the first electrode pattern designed in a planar form as shown in FIG. 5 into a corrected first electrode pattern that is corrected to fit the curved surface, and a laser according to the converted first electrode pattern. By irradiating, a first electrode pattern that perfectly matches the design can be formed.

 Here, the corrected first electrode pattern may be formed by projecting a curved electrode pattern formed at regular intervals on a curved surface into a flat surface, thereby forming an electrode pattern having the same spacing on a curved surface, although the spacing is not the same.

While the surface of the first electrode pattern region is irradiated by irradiating the laser, surface alignment of the alignment mark region may be simultaneously performed so as to be accurately aligned with the second electrode substrate as shown in FIG. 6.

More specifically, when the base electrode substrate and the second electrode substrate are laminated, it is a three-dimensional shape, and if not, the product may have defects, so it needs to be aligned and laminated at the correct location.

To this end, when the surface of the first electrode pattern region is modified through the laser, surface modification is performed on the alignment mark region specifying the location to be joined with the second electrode substrate and plating is performed, and alignment with the first electrode is performed. Marks are patterned simultaneously.

Therefore, the alignment mark and the second electrode substrate can be aligned and placed at the correct position. The alignment mark may be formed of a mark indicating a boundary to be coupled with the second electrode substrate or a mark indicating a position where an elastic body is coupled.

Alternatively, the first electrode pattern is designed as a 3D curved electrode pattern, and the position of a specific region to be patterned in the designed 3D curved electrode pattern is specified as coordinates, and the laser coordinates considering the specific region coordinates and the irradiation direction of the laser device and It is possible to form an accurate electrode pattern for a 3D curved surface by controlling the laser device so that the laser is irradiated only in the specific area by synchronization.

When the first electrode pattern region is surface-modified on the base substrate 110 of the three-dimensional shape as described above, the first electrode 130 is formed by forming an electrode only in the region where the first electrode pattern is formed through plating.

More specifically, when the first electrode pattern region processed by the laser is surface-modified and electroplating is performed through electroless plating using nickel and copper, the first electrode pattern whose surface is modified by laser irradiation of the base substrate. The first electrode 130 is formed by fixing the conductive material only in the region.

The surface of the first electrode pattern formed through the laser irradiation has a high roughness (surface roughness) due to surface modification, thereby increasing the bonding strength with a conductive material during plating.

Next, looking at the second method, the step of forming a laser pigment layer 120 by applying a laser pigment on the base substrate of the three-dimensional shape (Fig. 3 a), and the base substrate on which the laser pigment layer is formed Forming a first electrode pattern by irradiating a laser corresponding to the one electrode pattern designed on the image (b in FIG. 3), and forming a conductive electrode pattern through electroplating on the first electrode pattern (FIG. 3) The base electrode substrate on which the first electrode is formed is completed, including c).

The laser pigment may be composed of an insulator and a resin molded body, and may be formed by applying a laser pigment layer on a base substrate having a geometric shape, activated by a laser, or spray spraying or coating.

The laser pigment serves to modify the area to be plated on the surface of the laser pigment layer to have properties suitable for plating by irradiating a laser to the area to be plated on the surface. That is, a laser is directly irradiated to a predetermined area of the laser pigment to selectively expose a metal component in the non-conductive metal compound, and electroless plating is performed on the area to form a conductive pattern.

More specifically, the laser pigment is formed of a plating seed by adding a metal organic compound in a polymer resin, and the laser decomposes the metal organic compound by a chemical reaction by photochemical reaction. Among them, the metal element is formed only on the laser patterned portion, and serves as a plating seed during electroless plating.

The laser pigment layer 120 plays a role similar to that of the photoresist PR for selective patterning because the surface of the portion corresponding to the electrode pattern is modified through the characteristics activated by the laser to specify the plating area.

When the first electrode pattern is formed on the base substrate 110 having the laser pigment layer 120 formed as described above, the electrode is formed only in the region where the first electrode pattern is formed through electroless plating using nickel and copper. Thus, the first electrode 130 is formed.

More specifically, since the laser pigment layer 120 is composed of an insulator, when electroplating through electroless plating is performed, a conductive material is fixed only to the first electrode pattern region whose surface is modified by laser irradiation of the laser pigment layer. The first electrode 130 is formed.

* The surface of the first electrode pattern formed through the laser irradiation has a high roughness (surface roughness) due to surface modification, so that a bonding strength with a conductive material can be enhanced when plating.

Here, the conductive material may be any material having conductivity, and may be formed of any one selected from Cr, Ni, Al, Ti, Ag, and Au, or alloys thereof.

Lastly, with reference to the third method, after depositing or plating a conductive material on a three-dimensionally shaped base substrate, laser marking other than the first electrode may form a base electrode substrate.

More specifically, after forming a conductive material layer by depositing or plating a conductive material on the surface of the base substrate, the area other than the first electrode is irradiated with a laser to remove all areas except the first electrode to remove the base. The first electrode can be directly formed on the substrate.

It is apparent that the embodiments of FIGS. 5 and 6 can be applied to the second and third methods.

When the base electrode substrate is formed as described above, a touch pressure sensor is manufactured by laminating with the second electrode substrate. (D in FIGS. 2 and 3)

More specifically, after forming the second electrode on the substrate base material, an elastic body is formed on the substrate base material on which the second electrode is formed to manufacture a second electrode substrate and to be laminated with the prepared base electrode substrate.

The elastic body may be arranged to be arranged at regular intervals in a plurality of columnar shapes, and may be composed of an elastic layer covering the entire upper portion of the lower electrode layer.

In the detailed description of the present invention described above, the preferred embodiments of the present invention have been described, but the protection scope of the present invention is not limited to the above embodiments, and those of ordinary skill in the art will appreciate the present invention. It will be understood that various modifications and changes can be made to the present invention without departing from the spirit and scope of the technology.

10: base electrode substrate 20: second electrode substrate

Claims (7)

A method of manufacturing a touch pressure sensor that senses a magnitude of pressure by recognizing a changed capacity in an elastic body between two electrodes when pressed,
Manufacturing a base electrode substrate by directly forming a first electrode using a laser and plating directly on a base substrate as an injection material without a separate first substrate;
And laminating the base electrode substrate and the second electrode substrate on which the elastic body is formed;
The manufacturing of the base electrode substrate may include preparing and preparing a base substrate having a three-dimensional shape formed of a thermoplastic resin by injection molding;
And forming a first electrode pattern by irradiating a laser corresponding to the one electrode pattern according to a pattern path program designed on the base substrate;
The manufacturing of the base electrode substrate is
Forming a laser pigment layer by applying a laser pigment on a base substrate having a three-dimensional shape, and irradiating a laser in response to a 1-electrode pattern according to a pattern path program designed on the base substrate on which the laser pigment layer is formed One electrode pattern is formed, and the pattern path program converts the first electrode pattern designed in a flat form into a corrected first electrode pattern that corrects to fit a curved surface of a three-dimensional shape, wherein the corrected first electrode pattern is constant on the curved surface. Forming a first electrode pattern by projecting a curved electrode pattern formed at intervals into a plane to conform to three-dimensional shape characteristics, and forming a first electrode by electroconductive bonding to the first electrode pattern through electroplating Forming a first electrode directly on the injection material, including the step of forming a base electrode substrate by Manufacturing method of 3D shape pressure touch sensor as a gong.
delete According to claim 1,
The manufacturing of the base electrode substrate is
After forming a conductive material layer by depositing or plating a conductive material on the surface of the three-dimensional shape of the base substrate, a region other than the first electrode is irradiated with a laser to remove all of the regions except the first electrode on the base substrate. Method of manufacturing a three-dimensional shape pressure touch sensor, characterized in that the first electrode is formed directly.
The method of claim 1 or 3,
The three-dimensional shape
As a basis for elevation, as well as regular three-dimensional shapes such as hemispherical and elliptical, the elevation includes irregular three-dimensional shapes such as a free curve or a mixture of curves and straight lines;
The base substrate having the three-dimensional shape
Method for manufacturing a three-dimensional pressure touch sensor, characterized in that it is manufactured in a three-dimensional shape suitable for a design purpose by injection of synthetic resin material.
delete According to claim 1,
The pattern path program
Designing a first electrode pattern as a 3D curved electrode pattern, specifying a location of a specific area to be patterned in the designed 3D curved electrode pattern, and synchronizing the specific area coordinates with laser coordinates considering laser irradiation directions of the laser device Method for manufacturing a 3D shape pressure touch sensor, characterized in that it is possible to form an accurate electrode pattern for a 3D curved surface by controlling the laser device so that the laser is irradiated only in the area.
According to claim 1,
Forming a first electrode pattern by irradiating the laser is
Simultaneously performing surface modification of the alignment mark region so as to accurately align when laminating with the second electrode substrate while surface-modifying the first electrode pattern region by irradiating the laser,
The step of forming the base electrode substrate is
A method of manufacturing a three-dimensional shape pressure touch sensor, characterized in that a conductive material is fixed to the first electrode pattern through electroplating to simultaneously form the first electrode and the alignment mark.

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