JP2002303505A - Surface shape recognizing sensor chip and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To mount a surface shape recognizing sensor chip for recognizing a surface shape such as a finger print with a higher yield. SOLUTION: Inside a sensor area 151 of a substrate 101 in the surface shape recognizing sensor chip 100, a plurality of metallic patterns 104a and a grid- shaped metallic pattern 106a are formed, while a frame-shaped metallic pattern 106b surrounding the sensor area 151 is formed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface shape recognizing sensor chip used for detecting a surface shape having minute irregularities such as a human fingerprint or an animal nose pattern, and a method of manufacturing the same.

[0002]

2. Description of the Related Art With the progress of the information society and the environment of the modern society, interest in security technology is increasing.
For example, in the information-oriented society, personal authentication technology for system construction such as electronic cashing is an important key. In addition, research and development on authentication technologies to prevent theft and unauthorized use of credit cards are being actively conducted (for example, Yoshimasa Shimizu et al.,
Study on IC card with personal authentication function, IEICE Technical Report of IEICE OFS92-32, P25 30 (199
2)).

[0003] There are various authentication methods such as fingerprint and voice.
Above all, many technologies have been developed for fingerprint authentication technology. Fingerprint authentication methods are broadly classified into an optical reading method and a method of using human electrical characteristics and detecting unevenness of a fingerprint and replacing it with an electric signal. The optical reading method is a method of reading fingerprint data mainly by using light reflection and an image sensor (CCD) to perform collation (for example, Seigo Igaki et al., Personal collation method and apparatus, Japanese Patent Application Laid-Open No. 61-1986). 221883 publication). Further, a method of reading a pressure difference due to unevenness of a fingerprint using a piezoelectric thin film has also been developed (for example, Masanori Sumihara et al., Fingerprint sensor, JP-A-5-61965).

[0004] Further, an authentication method for detecting a fingerprint by detecting a change in resistance or detecting a change in capacitance using a pressure-sensitive sheet, thereby replacing a change in electrical characteristics caused by contact with the skin with a distribution of electric signals. (For example, Kazuhiro Hemi et al., Surface Shape Sensor, Individual Authenticator and Activated System Using It, JP-A-7-168)
930). However, in the conventional technology described above, first, the optical reading method is downsized,
Generalization is difficult, and the application is limited. Further, in the method of detecting the unevenness of the fingerprint using a pressure-sensitive sheet or the like, it is considered that the practical use is difficult or the reliability is poor due to the special material and the difficulty in workability.

On the other hand, "Marco Tartagni" developed a capacitive fingerprint sensor using LSI manufacturing technology (Marco Tartagni).
Tartagni and Robert Guerrieri, A 390 dpi Live Finge
rprint Imager Based on Feedback Capacitive Sensin
g Scheme, 1997 IEEE International Solid-State Circuit
its Conference, p200 201 (1997)). This fingerprint sensor uses a feedback capacitance method to detect a skin uneven pattern using a sensor chip in which small capacitance detection sensors are two-dimensionally arranged on an LSI. The capacitance detection sensor is characterized in that a special interface is not required and the size can be reduced as compared with the conventional optical sensor.

[0006]

However, the reports so far mainly focus on the development of the fingerprint sensor itself, and did not discuss the fingerprint sensor structure at the time of mounting for actual use. is there. When mounting a fingerprint sensor chip, a technique of applying a protective material for protecting a bonding portion to a target portion from the viewpoint of reliability is particularly indispensable. However, there is a problem that the coating liquid used in this technique flows and covers an area (sensor area) for detecting the fingerprint sensor chip. When the sensor area is covered in this way, the fingerprint sensor chip becomes defective. Therefore, there is a need for development that avoids problems due to flow when applying a protective material.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has an object to provide a surface shape recognizing sensor chip for recognizing a surface shape such as a fingerprint with a higher yield. The purpose is to do.

[0008]

According to the present invention, there is provided a sensor chip for recognizing a surface shape, comprising: a plurality of sensor electrodes arranged in a sensor region on an interlayer insulating film on a substrate and each of which is insulated and separated; An insulating protective film formed on a region including the sensor region so as to cover the sensor electrode, and a sensor electrode on the interlayer insulating film separated from the sensor electrode and partially disposed together with the insulating protective film; And a ground electrode connected to an external connection terminal to which a predetermined fixed potential is applied outside the sensor region, and a predetermined distance from the insulating protection film inside the external connection terminal so as to surround the insulating protection film. An integration that detects the capacitance formed between the sensor electrode and the opposing recognition target surface when a part of the recognition target comes into contact with the surface of the insulating protective film when a frame-shaped bank formed on the substrate is touched. Consisting of circuits, It is obtained by a capacitance detecting means disposed under the interlayer insulating film on the plate. According to the invention,
When the surface shape recognition sensor chip is mounted, the flow of the protective material formed on the external connection terminal stops at the bank.

In the above invention, the bank is made of the same material as the earth electrode. The bank is
It is made of the same material as the insulating protective film.

According to another aspect of the present invention, there is provided a sensor chip for recognizing a surface shape, comprising: a plurality of sensor electrodes arranged in a sensor region on an interlayer insulating film on a substrate, each of which is insulated and separated; An insulating protective film formed in a region including the sensor region so as to cover the sensor electrode; and a sensor electrode disposed in the sensor region on the interlayer insulating film which is insulated and separated from the sensor electrode, and a part thereof is formed on one surface together with the insulating protective film. A ground electrode connected to an external connection terminal to which a predetermined fixed potential is applied outside the sensor area, and a frame-shaped groove formed outside the sensor area by a predetermined distance inside the periphery of the insulating protective film. And an integrated circuit that detects a capacitance formed between the sensor electrode and the surface of the object to be recognized facing the sensor electrode when a part of the object to be recognized comes into contact with the surface of the insulating protective film. Placed below A capacitance detection unit that, the external connection terminal, and is formed outside the insulating protective film. According to the present invention, when the sensor chip for surface shape recognition is mounted, the flow of the protective material formed on the external connection terminal stops at the frame-shaped groove.

In the above-mentioned invention, the ground electrode is formed in a lattice shape, and the sensor electrode is arranged at the center of the grid of the ground electrode formed in the lattice shape.

According to a method of manufacturing a sensor chip for recognizing a surface shape of the present invention, a step of forming an interlayer insulating film on a semiconductor substrate, a step of forming a first metal film on the interlayer insulating film, Forming a first mask pattern having a first opening in the sensor region on the first metal film, and plating the first metal film surface exposed at the bottom of the first opening by plating. Forming a first metal pattern, and removing the first mask pattern, and surrounding the sensor region outside the second opening and the sensor region disposed around the first metal pattern. Forming a second mask pattern having the arranged groove-shaped third opening on the first metal film and the first metal pattern; and forming the second mask pattern on the first opening and the third opening. By plating on the surface of the first metal film exposed at the bottom Forming the second metal pattern and the third metal pattern thicker than the first metal pattern, and removing the second mask pattern, and then forming the first metal pattern, the second metal pattern, and the third metal pattern. Etching the first metal film using the pattern as a mask,
A sensor electrode composed of the first metal film and the first metal pattern, a ground electrode composed of the first metal film and the second metal pattern, and a frame-shaped bank composed of the first metal film and the third metal pattern; And forming an insulating protective film on the interlayer insulating film in the region including the sensor region at a predetermined distance from the bank inside the bank so as to cover the sensor electrode and expose the upper portion of the ground electrode. Forming at least a step of forming an external connection terminal arranged outside the bank and connected to a ground electrode to be given a predetermined fixed potential, and forming a plurality of capacitance detecting elements constituted by sensor electrodes It is.

According to another aspect of the present invention, there is provided a method of manufacturing a sensor chip for recognizing a surface shape, comprising the steps of: forming an interlayer insulating film on a semiconductor substrate; forming a first metal film on the interlayer insulating film; Forming a first mask pattern having a plurality of first openings in a region of the first metal film in a sensor region on the first metal film; and a first metal film surface exposed at a bottom of the first opening. Forming a first metal pattern by a plating method, removing the first mask pattern, and then forming a second mask pattern having a second opening disposed around the first metal pattern. Forming the first metal film and the first metal pattern on the first metal pattern; and plating the second metal pattern on the first metal film surface exposed at the bottom of the second opening by plating. A process of forming thickly;
After removing the second mask pattern, the first metal film is etched away using the first metal pattern and the second metal pattern as a mask, and a sensor electrode including the first metal film and the first metal pattern is removed. Forming a ground electrode comprising a first metal film and a second metal pattern; and covering the sensor electrode and exposing an upper portion of the ground electrode on the interlayer insulating film in a region including the sensor region. Forming an insulating protective film provided with a frame-shaped groove outside the semiconductor device, and forming an external connection terminal disposed outside the insulating protective film and connected to a ground electrode to be given a predetermined fixed potential. At least a plurality of capacitance detecting elements constituted by sensor electrodes are formed.

In the above invention, the insulating protective film is made of a photosensitive resin, and the photosensitive resin is processed by photolithography to form a frame-shaped groove. The frame-shaped groove has an interlayer insulating film exposed at the bottom.

[0015]

Embodiments of the present invention will be described below with reference to the drawings. <First Embodiment> FIGS. 1 and 2 are process diagrams illustrating a method for manufacturing a sensor chip for surface shape recognition according to an embodiment of the present invention. Hereinafter, the manufacturing method will be described with reference to FIGS. First, as shown in FIG. 1A, an interlayer insulating film 101a is formed on a substrate 101 made of a semiconductor material such as silicon. Interlayer insulating film 101
Although not shown, another integrated circuit such as a detection circuit is formed on the substrate 101 below a, and has a wiring structure including a plurality of wirings.

After forming the interlayer insulating film 101a, first,
By a vapor deposition method, a titanium film having a thickness of 0.1 μm and a thickness of 0.1 μm are formed.
Then, a seed layer 102 composed of a two-layer film including a gold film of m is formed. Next, as shown in FIG.
A resist pattern 103 having an opening 103a and a thickness of about 5 μm is formed thereon. Resist pattern 103
Is formed by a known photolithography technique. After the resist pattern 103 is formed, a metal pattern 104a made of a gold plating film is formed on the seed layer 102 exposed at the opening 103a by electrolytic plating to a thickness of 1 μm.
m.

Next, after the resist pattern 103 is removed, as shown in FIG.
A resist pattern 105 having a thickness of about 5 μm and having a and 105b is formed. At this time, the resist pattern 10
5 covers the metal pattern 104a. After the resist pattern 105 is formed, the openings 105a, 1
A metal pattern 106a, 1 made of a gold plating film is formed on the seed layer 102 exposed at 05b by electrolytic plating.
06b is formed to a thickness of about 3 μm.

As a result, as shown in the plan view of FIG. 1D, a plurality of metal patterns 104a and a grid-like metal pattern 106a are formed in the sensor area 151 of the substrate 101 of the sensor chip 100 for surface shape recognition. Then, the frame-shaped metal pattern 106 is surrounded so as to surround the sensor area 151.
A state in which b is formed is obtained. Metal pattern 104a
Becomes a sensor electrode as described below, and the lattice-shaped metal pattern 106a becomes a ground electrode. Further, external connection terminals (pads) (not shown) are formed in a region outside the frame-shaped metal pattern 106b. The cross-sectional views shown in FIGS. 1A to 1C and FIGS. 2 to 5 show partial cross sections taken along line XX ′ of FIG. 1D.

Next, after the resist pattern 105 is removed, as shown in FIG.
06b, a plurality of metal patterns 1 serving as pads
08a is formed, and thereafter, the seed layer 102 is selectively etched using each metal pattern as a mask. In this etching, first, iodine, ammonium iodide,
The gold in the upper layer of the seed layer 102 is selectively removed using an etching solution composed of water and ethanol. Next, titanium under the seed layer 102 is selectively removed using an HF-based etchant. In the wet etching of gold,
The etching rate is 0.05 μm per minute.

As a result, as shown in FIG. 2B, the sensor electrode 10 whose upper layer is made of gold is formed on the interlayer insulating film 101a.
4 and an earth electrode 106 insulated from the sensor electrode 104. This earth electrode 106
For example, as shown in the plan view of FIG. 1 (d), it is formed in a lattice on the interlayer insulating film 101a. Further, a plurality of sensor electrodes 104 are arranged at the center of a region surrounded by the grid-like ground electrode 106. Also,
A frame-like bank 116 is formed outside the sensor region where the plurality of sensor electrodes 104 are arranged so as to surround the sensor region, and a plurality of external connection terminals (pads) 108 are arranged outside the bank 116. ing.

Next, as shown in FIG. 2C, a photosensitive resin film 107 is formed on the interlayer insulating film 101a by spin coating so as to cover the sensor electrode 104 and the ground electrode 106. The resin film 107 is formed in such a thickness that a film that can be removed by a development process described below is formed on the ground electrode 106. The resin film 107 has positive photosensitivity, and is obtained by adding a positive photosensitizer to a base resin such as polyamide, polyamic acid, or polybenzoxazole (or a precursor thereof).

The formed resin film 107 is subjected to a heat treatment by placing the substrate 101 on a hot plate at about 120 ° C. for about 4 minutes. Next, the area inside the bank 116 including the above-mentioned sensor area is shielded from light by a known photolithography technique, the area outside the bank 116 is exposed, and subsequently the development processing is performed. After this, about 31
A heat treatment at a temperature of 0 ° C. is performed to thermally cure the resin film 107, so that a region inside the bank 116 is covered with the insulating protective film 117 as shown in FIG. In addition, by this developing process, a part of the upper part of the resin film 107 is dissolved,
The upper portion of the ground electrode 106 is exposed on the insulating protective film 117.

Thereafter, as shown in FIG. 2E, the sensor chip 100 for surface shape recognition is mounted on the mounting substrate 210. In this mounting, the surface shape recognition sensor chip 10
The pad 108 disposed at the end of the substrate 101 of the first substrate 101 and the pin 211 of the mounting substrate 210 are connected by a wire 212, and a protective material 213 made of resin is used to protect the wire 212
To form Here, as described above, the sensor chip 100 for surface shape recognition in the present embodiment includes a plurality of pads 108 on the outermost periphery, and between the pads 108 and the sensor region 151 inside, that is, outside the sensor region, Embankment 11
6 was provided.

Therefore, when the resin coating liquid is dropped from above the wire 212 to form the protective material 213, the flow of the dropped coating liquid from the bank 116 to the inside of the surface shape recognition sensor chip 100 is suppressed. Become so. As a result, according to the present embodiment, when mounting the sensor chip 100 for surface shape recognition, the sensor region 151 is not covered with the formed protective material 213.

Although not shown, the interlayer insulating film 10
Below 1a, a wiring connected to the sensor electrode 104 is formed, and a capacitance detection circuit connected to this wiring and detecting a capacitance formed on the sensor electrode 104 is formed. The capacitance detection circuit is provided for each sensor electrode 104 and detects a capacitance formed between the sensor electrode 104 and the recognition target. The output of each capacitance detection circuit is also processed by processing means (not shown), and is converted into image data obtained by converting the capacitance formed on each sensor electrode 104 into light and shade. The input / output of the image data is performed via a predetermined pad 108.

The ground electrode 106 is formed on the interlayer insulating film 1.
A predetermined pad 108 is electrically connected by a wiring (not shown) formed below the pad 01a. The pad 108 connected to the ground electrode 106 may be connected to a ground line, for example, or may be in a state where a predetermined fixed potential is applied.

In the sensor chip 100 for surface shape recognition configured as described above, when the tip of the finger comes into contact with the insulating protective film 117 in the sensor area 151, each sensor electrode is formed according to the fingerprint shape of the contacted finger. The capacitance formed on 104 changes. Each sensor electrode 1 corresponding to this fingerprint shape
If the shading data is added in accordance with the change in the capacity formed on the memory cell 04, the shape of the fingerprint can be reproduced. In addition, static electricity generated when a finger contacts the surface of the insulating protective film 117 is
The current flows to the ground electrode 106, and the interlayer insulating film 10
The influence of static electricity on each circuit (not shown) arranged below 1a can be suppressed.

Second Embodiment Next, another embodiment of the present invention will be described. 3 and 4 are process diagrams illustrating a method for manufacturing a sensor chip for surface shape recognition according to another embodiment of the present invention. Hereinafter, the manufacturing method will be described with reference to FIGS. First, as shown in FIG. 3A, a substrate 1 made of a semiconductor material such as silicon is used.
First, an interlayer insulating film 101a is formed on the substrate 01. Although not shown, another integrated circuit such as a detection circuit is formed on the substrate 101 below the interlayer insulating film 101a, and has a wiring structure including a plurality of wirings.

After forming the interlayer insulating film 101a, first,
A titanium film having a thickness of 0.1 μm and a thickness of 0.1 μm are formed by an evaporation method.
Then, a seed layer 102 composed of a two-layer film including a gold film of m is formed. Next, as shown in FIG.
A resist pattern 103 having an opening 103a and a thickness of about 5 μm is formed thereon. Resist pattern 103
Is formed by a known photolithography technique. After the formation of the resist pattern 103, a metal pattern 104a made of a gold plating film is formed on the seed layer 102 exposed at the opening 103a by electrolytic plating to a thickness of 1 μm.
m. Up to this point, it is the same as the above-described embodiment.

Next, after removing the resist pattern 103, as shown in FIG. 3C, a resist pattern 305 having an opening 305a and a thickness of about 5 μm is formed. At this time, the metal pattern 104a is covered with the resist pattern 305. Resist pattern 30
After forming 5, a metal pattern 106a made of a gold plating film is formed on the seed layer 102 exposed in the opening 305a to a thickness of about 3 μm by electrolytic plating.
As a result, the plurality of metal patterns 10
4a and a grid-like metal pattern 106a are formed.

Next, after removing the resist pattern 305, the sensor electrode 104 whose upper layer is made of gold is formed on the interlayer insulating film 101a in the same manner as in FIGS. 2A and 2B of the above-described embodiment. And an earth electrode 106 which is insulated and separated from the sensor electrode 104.
8 is formed. However, at this stage of the present embodiment,
The bank 116 shown in FIG. 2B is not formed.

Next, as shown in FIG. 4A, a photosensitive resin film 107 is formed on the interlayer insulating film 101a by spin coating so as to cover the sensor electrode 104 and the ground electrode 106. The resin film 107 is formed in such a thickness that a film that can be removed by a development process described below is formed on the ground electrode 106. Resin film 10 formed
7, the substrate 10 is placed on a hot plate at about 120 ° C.
1 is placed for about 4 minutes to perform a heat treatment.

Next, by a known photolithography technique, a predetermined area including the above-described sensor area and an outer frame-shaped area at a certain interval from this area are shielded from light,
Exposure is performed to the region between these and the region outside the frame-shaped region, and subsequently the developing process is performed. Thereafter, a heat treatment at a temperature of about 310 ° C. is performed to thermally cure the resin film 107, and as shown in FIG.
And the frame-shaped bank 126 is covered with the insulating protective film 12.
7 is arranged outside the area.

The embankment 126 is formed by leaving a light-shielded region in the shape of a frame in the photolithography by development. By this developing process, a part of the upper part of the resin film 107 is dissolved, and the upper part of the ground electrode 106 is exposed on the insulating protective film 127. In FIG. 4B, the bank 126 is formed so as to be separated from the insulating protective film 127. However, the present invention is not limited to this. It is sufficient that a frame-shaped groove is formed between the bank 126 and the insulating protective film 127, and the bank 126 and the insulating protective film 127 may be connected at the bottom of the groove. In other words, the insulating protective film is formed up to the bank 126 in FIG. 4B, and a frame-shaped groove is formed inside the insulating protective film at a predetermined distance from the periphery. Is also good.

Thereafter, as shown in FIG. 4C, the sensor chip 100 for surface shape recognition is mounted on the mounting board 210. In this mounting, similarly to the state shown in FIG. 2E, the pads 108 arranged at the end of the substrate 101 of the surface shape recognition sensor chip 100 and the pins 211 of the mounting substrate 210 are connected by wires 212. Then, a protective material 213 made of resin is formed to protect the wires 212. Here, as described above, the sensor chip 100 for surface shape recognition according to the present embodiment has a plurality of pads 10 on the outermost periphery.
8, and a bank 126 is provided between the inside and the sensor area 151, that is, outside the sensor area.

Therefore, when the coating liquid of the resin is dropped from above the wire 212 to form the protective material 213, it is suppressed that the dropped coating liquid flows from the bank 126 into the inside of the sensor chip 100 for surface shape recognition. Become so. As a result, also in the present embodiment, when mounting the sensor chip 100 for surface shape recognition, the sensor region 151 is not covered with the formed protective material 213.

[0037]

As described above, according to the present invention,
Since a bank and a groove are formed outside the sensor area, the flow of applying the protective material at the time of mounting can suppress the defect that the sensor area is covered with the protective material due to the flow when applying the protective material, such as a fingerprint. An excellent effect is obtained that the surface shape recognition sensor chip for recognizing the surface shape can be mounted at a higher yield.

[Brief description of the drawings]

FIG. 1 is a process chart for describing a method of manufacturing a sensor chip for surface shape recognition according to an embodiment of the present invention.

FIG. 2 is a process drawing following FIG. 1 for explaining a method of manufacturing a sensor chip for surface shape recognition.

FIG. 3 is a process chart for explaining a method of manufacturing a sensor chip for surface shape recognition according to another embodiment of the present invention.

FIG. 4 is a process drawing following FIG. 3 for explaining a method of manufacturing the sensor chip for surface shape recognition.

[Explanation of symbols]

100: sensor chip for surface shape recognition, 101: substrate,
101a: interlayer insulating film, 102: seed layer, 103: resist pattern, 103a: opening, 104: metal pattern, 104a: lower electrode, 105: resist pattern, 105a, 105b: opening, 106a, 106b
... metal pattern, 106 ... ground electrode, 107 ... resin film, 108 ... pad, 108a ... metal pattern, 116
... bank, 117 ... insulating protective film, 151 ... sensor area, 2
10 mounting board, 211 pin, 212 wire, 21
3. Protective material.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Satoshi Shigematsu 2-3-1 Otemachi, Chiyoda-ku, Tokyo Nippon Telegraph and Telephone Corporation (72) Inventor Hiroki Morimura 2-3-3, Otemachi, Chiyoda-ku, Tokyo No. 1 Inside Nippon Telegraph and Telephone Corporation (72) Inventor Yasuyuki Tanabe 2-3-1 Otemachi, Chiyoda-ku, Tokyo F-term within Nippon Telegraph and Telephone Corporation (reference) 2F063 AA41 BB10 CA40 DA02 HA04 5B047 AA25 BB04 BC01 5F038 AZ07 DF06 EZ17 EZ20

Claims (9)

[Claims] A plurality of sensor electrodes disposed in a sensor region on an interlayer insulating film on a substrate and each of which is insulated and separated; and a region including the sensor region on the interlayer insulating film, covering the sensor electrode. An insulating protective film formed on the sensor electrode, wherein the sensor electrode is disposed in the sensor region on the interlayer insulating film that is insulated and separated from the sensor electrode, and a part thereof forms one surface together with the insulating protective film; A ground electrode connected to an external connection terminal to which a predetermined fixed potential is applied outside the region; and an inner side of the external connection terminal, on the substrate so as to surround the insulating protective film at a predetermined distance from the insulating protective film. An integrated frame for detecting a capacitance formed between the sensor electrode and the surface of the recognition object facing the sensor electrode when a part of the object to be recognized comes into contact with the surface of the insulating protective film; circuit Rannahli, the surface shape recognition sensor chip is characterized in that a capacitance detecting means disposed under the interlayer insulating film on the substrate. 2. The surface shape recognition sensor chip according to claim 1, wherein the bank is made of the same material as the ground electrode. 3. The sensor chip for surface shape recognition according to claim 1, wherein the bank is made of the same material as the insulating protective film. 4. A plurality of sensor electrodes disposed in a sensor region on an interlayer insulating film on a substrate and each of which is insulated and separated, and a region including the sensor region on the interlayer insulating film, covering the sensor electrode. An insulating protective film formed on the sensor electrode, wherein the sensor electrode is disposed in the sensor region on the interlayer insulating film that is insulated and separated from the sensor electrode, and a part thereof forms one surface together with the insulating protective film; A ground electrode connected to an external connection terminal to which a predetermined fixed potential is applied outside the region, a frame-shaped groove formed inside the periphery of the insulating protective film by a predetermined distance and outside the sensor region; When a part of the object comes into contact with the surface of the insulating protective film, the integrated circuit detects a capacitance formed between the sensor electrode and the surface of the recognition object facing the sensor electrode. Insulation A capacitance detection unit disposed below the external connection terminals, the surface shape recognition sensor chip characterized in that from the insulating protective film formed outside. 5. The sensor chip for recognizing a surface shape according to claim 1, wherein the ground electrode is formed in a lattice shape, and is provided at a center of a grid of the ground electrode formed in the lattice shape. A sensor chip for surface shape recognition, wherein the sensor electrode is disposed. 6. A step of forming an interlayer insulating film on a semiconductor substrate, a step of forming a first metal film in the interlayer insulating film, and a first step having a plurality of first openings in a predetermined region. Forming a mask pattern in the sensor region on the first metal film; and forming a first metal pattern on the surface of the first metal film exposed at the bottom of the first opening by plating. And after removing the first mask pattern, a second opening disposed around the first metal pattern, and a groove formed outside the sensor region so as to surround the sensor region. Forming a second mask pattern having a third opening on the first metal film and the first metal pattern; and a bottom of the second opening and the third opening. Plating on the surface of the first metal film exposed to Forming a second metal pattern and a third metal pattern thicker than the first metal pattern; and removing the second mask pattern, and then removing the first metal pattern, the second metal pattern, And removing the first metal film by etching using the third metal pattern as a mask, a sensor electrode including the first metal film and the first metal pattern, the first metal film, and the second metal film.
Forming a ground electrode made of a metal pattern and a frame-shaped bank made of the first metal film and the third metal pattern; and a predetermined distance from the bank inside the bank, Forming an insulating protective film on the interlayer insulating film in a region including the sensor region so as to cover the sensor electrode and expose the upper portion of the ground electrode; and disposing the insulating protective film outside the bank and connecting to the ground electrode. Forming an external connection terminal to which a predetermined fixed potential is applied, and forming a plurality of capacitance detecting elements constituted by the sensor electrodes. . 7. A step of forming an interlayer insulating film on a semiconductor substrate, a step of forming a first metal film in the interlayer insulating film, and a first step having a plurality of first openings in a predetermined region. Forming a mask pattern in the sensor region on the first metal film; and forming a first metal pattern on the surface of the first metal film exposed at the bottom of the first opening by plating. After removing the first mask pattern, a second mask pattern having a second opening disposed around the first metal pattern is provided with the first metal film and the first mask pattern.
Forming a second metal pattern thicker than the first metal pattern on the surface of the first metal film exposed at the bottom of the second opening by plating. Removing the second mask pattern, etching and removing the first metal film using the first metal pattern and the second metal pattern as a mask, and removing the first metal film and the first metal film; Forming a sensor electrode composed of a pattern and a ground electrode composed of the first metal film and the second metal pattern; and covering the sensor electrode with the interlayer insulating film in a region including the sensor region; Forming an insulating protective film having a frame-shaped groove outside the sensor region, exposing an upper portion of the ground electrode, and disposing the insulating protective film outside the sensor region and contacting the ground electrode. Manufacturing a sensor chip for recognizing a surface shape, wherein at least a step of forming an external connection terminal to which a predetermined fixed potential is applied is provided, and a plurality of capacitance detecting elements constituted by the sensor electrodes are formed. Method. 8. The method for manufacturing a sensor chip for recognizing a surface shape according to claim 7, wherein the insulating protective film is made of a photosensitive resin, and the photosensitive resin is processed by a photolithography technique. Forming a groove by using the method described above. 9. The method for manufacturing a sensor chip for surface shape recognition according to claim 7, wherein the frame-shaped groove has the interlayer insulating film exposed at the bottom. Manufacturing method of sensor chip.