Fingerprint sensor, method for manufacturing the same, and display device including the same

Abstract

The present invention relates to a fingerprint sensor capable of increasing the amount of light incident on a light-sensing part by increasing the transmittance of the opening of a collimator, a method for manufacturing the same, and a display device including the same. In one embodiment, the fingerprint sensor comprises a light-sensing layer including a light-sensing element through which a detection current flows according to incident light, and a collimator layer disposed on the light-sensing layer. The collimator layer comprises first light-transmitting films disposed spaced apart from each other, a light-blocking film disposed between the first light-transmitting films, and a second light-transmitting film disposed between each of the first light-transmitting films and the light-blocking film.

Description

Technology Field

[0001] The present invention relates to a fingerprint sensor, a method for manufacturing the same, and a display device including the same. Background Technology

[0002] Display devices are applied to various electronic devices, such as smartphones, tablets, notebook computers, monitors, and TVs. Recently, due to the development of mobile communication technology, the use of portable electronic devices such as smartphones, tablets, and notebook computers has increased significantly. Portable electronic devices store privacy information such as contacts, call history, messages, photos, memos, user web browsing data, location data, and financial information. Therefore, fingerprint authentication, which verifies the user's biometric fingerprints, is used to protect the privacy information of portable electronic devices. In this case, the display device may include a fingerprint sensor for fingerprint authentication. The fingerprint sensor can be implemented using optical, ultrasonic, or capacitive methods. An optical fingerprint sensor may include a light-sensing unit that detects light, an aperture that provides light to the light-sensing unit, and a collimator having a light-blocking unit that blocks light.

[0003] On the other hand, if the fingerprint sensor is placed in the bezel area or non-display area of ​​the display device, there are limitations to expanding the display area. Therefore, recently, fingerprint sensors are being placed within the display area of ​​the display device. In this case, since the fingerprint sensor is positioned at the bottom of the display panel, the amount of light incident on the light-sensing part of the fingerprint sensor may be small. However, if the area of ​​the light-blocking part of the collimator is reduced to increase the amount of light incident on the light-sensing part of the fingerprint sensor, the noise light incident on the light-sensing part may increase. In this case, the accuracy of fingerprint recognition may decrease. The problem to be solved

[0004] The problem that the present invention aims to solve is to provide a fingerprint sensor capable of minimizing noise light incident on a light-sensing part even when the area of ​​the light-blocking part of the collimator is reduced, a method for manufacturing the same, and a display device including the same.

[0005] The problems of the present invention are not limited to those mentioned above, and other unmentioned technical problems will be clearly understood by those skilled in the art from the description below. means of solving the problem

[0006] In one embodiment for solving the above problem, a fingerprint sensor comprises a light sensing layer including a light sensing element through which a sensing current flows according to incident light, and a collimator layer disposed on the light sensing layer. The collimator layer comprises first light-transmitting films disposed spaced apart from each other, a light-blocking film disposed between the first light-transmitting films, and a second light-transmitting film disposed between each of the first light-transmitting films and the light-blocking film.

[0007] A display device according to one embodiment for solving the above problem comprises a display panel for displaying an image and a fingerprint sensor disposed on one surface of the display panel and detecting light passing through the display panel. The fingerprint sensor comprises a light-sensing layer including a light-sensing element through which a detection current flows according to incident light, and a collimator layer disposed on the light-sensing layer. The collimator layer comprises first light-transmitting films disposed spaced apart from each other, a light-blocking film disposed between the first light-transmitting films, and a second light-transmitting film disposed between each of the first light-transmitting films and the light-blocking film.

[0008] A method for manufacturing a fingerprint sensor in one embodiment for solving the above problem comprises the steps of: forming a light-sensing layer including a light-sensing element through which a sensing current flows according to incident light; forming a light-transmitting layer by depositing an organic material on the light-sensing layer; forming mask patterns on the light-transmitting layer; etching the light-transmitting layer according to the mask patterns to form first light-transmitting films; removing the mask patterns; forming a second light-transmitting film by depositing an inorganic material on the first light-transmitting films; and forming a light-blocking film by depositing an organic material on the second light-transmitting film.

[0009] Specific details of other embodiments are included in the detailed description and drawings. Effects of the invention

[0010] According to the fingerprint sensor, the method of manufacturing the same, and the display device including the same according to the embodiments, a second light-transmitting film is disposed between each of the first light-transmitting films and the light-blocking film, and the refractive index of the first light-transmitting film is substantially the same as the refractive index of the second light-transmitting film. Accordingly, light that can be detected as noise among the light incident on the light-sensing element can be minimized, thereby increasing the accuracy of fingerprint recognition of a finger.

[0011] In addition, according to the fingerprint sensor, the method of manufacturing the same, and the display device including the same according to the embodiments, the refractive index of the first light-transmitting film is higher than the refractive index of the second light-transmitting film. Accordingly, the amount of light incident on the light-sensing element through the opening of the collimator layer can be increased.

[0012] In addition, according to the fingerprint sensor, the method of manufacturing the same, and the display device including the same, by placing a color filter, such as a green color filter or a cyan color filter, on the second light-transmitting film and the light-blocking film, infrared light, which is noise light incident on the light-sensing element, can be blocked.

[0013] In addition, according to the fingerprint sensor, the method of manufacturing the same, and the display device including the same, a second light-transmitting film is formed on the first light-transmitting films, so that even if the first light-transmitting films are over-etched in the etching process and the width of each of the first light-transmitting films is reduced, the reduced width of each of the first light-transmitting films can be compensated by the width of the second light-transmitting film. Therefore, it is possible to prevent the light transmittance of the aperture from being lowered.

[0014] The effects according to the embodiments are not limited to those exemplified above, and a wider variety of effects are included in this specification. Brief explanation of the drawing

[0015] FIG. 1 is a perspective view showing a display device according to one embodiment. Figure 2 is a perspective view showing the fingerprint sensor of Figure 1. FIG. 3 is a cross-sectional view showing an example of a display panel and a fingerprint sensor cut along I-I' of FIG. 1. Figure 4 is an enlarged cross-sectional view showing in detail an example of a display panel in area A of Figure 3. Figure 5 is an enlarged cross-sectional view showing in detail an example of a fingerprint sensor in area A of Figure 3. FIGS. 6 to 8 are example drawings showing the direction of light propagation according to the refractive index of the first light-transmitting film and the refractive index of the second light-transmitting film in FIG. 5. Figure 9 is a graph showing the light transmittance of the aperture according to the angle of incidence of light, according to the refractive index of the second light-transmitting film. FIG. 10 is an enlarged cross-sectional view showing in detail another example of a fingerprint sensor in area A of FIG. 3. FIG. 11 is an enlarged cross-sectional view showing in detail another example of a fingerprint sensor in area A of FIG. 3. FIG. 12 is an enlarged cross-sectional view showing in detail another example of a fingerprint sensor in area A of FIG. 3. FIG. 13 is an enlarged cross-sectional view showing in detail another example of a fingerprint sensor in area A of FIG. 3. FIG. 14 is an enlarged cross-sectional view showing in detail another example of a fingerprint sensor in area A of FIG. 3. FIG. 15 is a flowchart showing a method for manufacturing a fingerprint sensor according to one embodiment. FIGS. 16 to 21 are exemplary drawings for explaining the method of manufacturing the fingerprint sensor of FIG. 15. FIG. 22 is a flowchart showing a method for manufacturing a fingerprint sensor according to another embodiment. FIGS. 23 and FIGS. 24 are example drawings for explaining the method of manufacturing the fingerprint sensor of FIG. 22. Specific details for implementing the invention

[0016] The advantages and features of the present invention and the methods for achieving them will become clear by referring to the embodiments described below in detail together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below but may be implemented in various different forms. These embodiments are provided merely to ensure that the disclosure of the present invention is complete and to fully inform those skilled in the art of the scope of the invention, and the present invention is defined only by the scope of the claims.

[0017] When elements or layers are referred to as being "on" another element or layer, this includes cases where another layer or element is interposed directly on or in the middle of another element. Throughout the specification, the same reference numerals refer to the same components. Shapes, sizes, ratios, angles, numbers, etc., disclosed in the drawings for describing embodiments are exemplary and the invention is not limited to the depicted details.

[0018] Although terms such as "first," "second," etc., are used to describe various components, it goes without saying that these components are not limited by these terms. These terms are used merely to distinguish one component from another. Therefore, it goes without saying that the first component mentioned below may also be the second component within the technical scope of the present invention.

[0019] The features of each of the various embodiments of the present invention may be combined or combined with one another, either partially or wholly, and may technically enable various interlocking and operation. Each embodiment may be implemented independently of one another or may be implemented together in an associated relationship.

[0020] Specific embodiments will be described below with reference to the attached drawings.

[0021] FIG. 1 is a perspective view showing a display device according to one embodiment.

[0022] Referring to FIG. 1, the display device (10) is a device for displaying video or still images and can be used as a display screen for various products such as televisions, laptops, monitors, billboards, and the Internet of Things (IOT), as well as portable electronic devices such as mobile phones, smartphones, tablet PCs, smart watches, watch phones, mobile communication terminals, electronic notebooks, electronic books, PMPs (portable multimedia players), navigation systems, and UMPCs (Ultra Mobile PCs).

[0023] The display device (10) may be a light-emitting display device such as an organic light-emitting display device using an organic light-emitting diode, a quantum dot light-emitting display device including a quantum dot light-emitting layer, an inorganic light-emitting display device including an inorganic semiconductor, and a micro light-emitting display device using a micro light-emitting diode (LED). Although the following description focuses on the display device (10) being an organic light-emitting display device, the present invention is not limited thereto.

[0024] The display device (10) includes a display panel (100), a display driving circuit (200), a circuit board (300), and a fingerprint sensor (400).

[0025] The display panel (100) may be formed as a rectangular plane having a short side in a first direction (X-axis direction) and a long side in a second direction (Y-axis direction) that intersects the first direction (X-axis direction). The corner where the short side in the first direction (X-axis direction) and the long side in the second direction (Y-axis direction) meet may be formed rounded to have a predetermined curvature or formed at a right angle. The planar shape of the display panel (100) is not limited to a rectangle and may be formed as other polygons, circles, or ellipses. The display panel (100) may be formed flat, but is not limited thereto. For example, the display panel (100) may include curved surfaces formed at the left and right ends that have a constant curvature or a changing curvature. In addition, the display panel (100) may be formed flexibly so that it can be bent, curved, folded, or rolled.

[0026] The display panel (100) may include a main area (MA) and a sub area (SBA).

[0027] The main area (MA) may include a display area (DA) that displays an image and a non-display area (NDA) that is a surrounding area of ​​the display area (DA). The display area (DA) may include display pixels that display an image. The non-display area (NDA) may be defined as an area extending from the outside of the display area (DA) to the edge of the display panel (100).

[0028] The display area (DA) may include a fingerprint detection area (FSA). The fingerprint detection area (FSA) refers to an area where a fingerprint sensor (400) is placed. The fingerprint detection area (FSA) may be a part of the display area (DA) as shown in FIG. 1, but is not limited thereto. The fingerprint detection area (FSA) may be the entire area of ​​the display area (DA) and may be substantially identical to the display area (DA).

[0029] A sub-region (SBA) may protrude in a second direction (Y-axis direction) from one side of a main region (MA). The length of the sub-region (SBA) in a first direction (X-axis direction) is smaller than the length of the main region (MA) in a first direction (X-axis direction), and the length of the sub-region (SBA) in a second direction (Y-axis direction) may be smaller than the length of the main region (MA) in a second direction (Y-axis direction), but is not limited thereto.

[0030] In FIG. 1, the sub-region (SBA) is illustrated as being unfolded, but the sub-region (SBA) can be bent, in which case it can be placed on the lower surface of the display panel (100). When the sub-region (SBA) is bent, it can overlap with the main region (MA) in the thickness direction (Z-axis direction) of the substrate (SUB). A display driving circuit (200) can be placed in the sub-region (SBA).

[0031] The display driving circuit (200) can generate signals and voltages to drive the display panel (100). The display driving circuit (200) may be formed as an integrated circuit (IC) and attached to the display panel (100) using a COG (chip on glass) method, a COP (chip on plastic) method, or an ultrasonic bonding method, but is not limited thereto. For example, the display driving circuit (200) may be attached to the circuit board (300) using a COF (chip on film) method.

[0032] The circuit board (300) can be attached to one end of a sub-region (SBA) of the display panel (100) using an anisotropic conductive film. As a result, the circuit board (300) can be electrically connected to the display panel (100) and the display driving circuit (200). The display panel (100) and the display driving circuit (200) can receive digital video data, timing signals, and driving voltages through the circuit board (300). The circuit board (300) may be a flexible printed circuit board, a printed circuit board, or a flexible film such as a chip-on-film.

[0033] A fingerprint sensor (400) may be placed on the lower surface of a display panel (100). The fingerprint sensor (400) may be attached to the lower surface of the display panel (100) using a transparent adhesive member. For example, the transparent adhesive member may be a transparent adhesive film such as an OCA (optically clear adhesive) film or a transparent adhesive resin such as an OCR (optically clear resin).

[0034] Figure 2 is a perspective view showing the fingerprint sensor of Figure 1.

[0035] Referring to FIG. 2, the fingerprint sensor (400) may include a fingerprint detection layer (410) and a collimator layer (420).

[0036] The fingerprint detection layer (410) may include sensor pixels arranged in a first direction (X-axis direction) and a second direction (Y-axis direction). Each of the sensor pixels may include a light-sensing element through which a detection current flows according to incident light, at least one transistor connected to the light-sensing element, and at least one capacitor connected to the light-sensing element or the transistor. The light-sensing element may be a photodiode or a phototransistor.

[0037] A collimator layer (420) is disposed on a fingerprint detection layer (410). The collimator layer (420) includes openings (OA) arranged in a first direction (X-axis direction) and a second direction (Y-axis direction) and light-blocking portions (LSA) disposed between the openings (OA). Each of the openings (OA) is a region that transmits light, and the light-blocking portions (LSA) may be a region that blocks light. Each of the openings (OA) may have a circular planar shape as shown in FIG. 2, but is not limited thereto. Each of the openings (OA) may have an elliptical or polygonal planar shape.

[0038] A fingerprint circuit board (500) may be disposed on the fingerprint detection layer (410) that is not covered by the collimator layer (420). The fingerprint circuit board (500) may be attached to the upper surface of the fingerprint detection layer (410) that is not covered by the collimator layer (420) using an anisotropic conductive film. As a result, the fingerprint circuit board (500) may be electrically connected to the sensor pixels of the fingerprint detection layer (410). Therefore, each of the sensor pixels of the fingerprint detection layer (410) may output a detection voltage according to the detection current of the light-sensing element through the fingerprint circuit board (500). The fingerprint driving circuit (510) electrically connected to the fingerprint circuit board (500) may recognize the fingerprint pattern of the finger according to the detection voltages of the sensor pixels.

[0039] The fingerprint driving circuit (510) may be placed on the fingerprint circuit board (500) as shown in FIG. 2, but is not limited thereto. The fingerprint driving circuit (510) may be placed on a separate circuit board electrically connected to the fingerprint circuit board (500). The fingerprint circuit board (500) may be a flexible printed circuit board, a printed circuit board, or a flexible film such as a chip-on-film.

[0040] FIG. 3 is a cross-sectional view showing an example of a display panel and a fingerprint sensor cut along I-I' of FIG. 1. FIG. 3 illustrates a case where a user touches a finger (F) to a display device (10) for fingerprint recognition.

[0041] Referring to FIG. 3, the display device (10) further includes a cover window (CW) disposed on the upper surface of the display panel (100). The cover window (CW) may be disposed on the upper surface of the display panel (100) to cover the upper surface of the display panel (100). The cover window (CW) may serve to protect the upper surface of the display panel (100). The cover window (CW) may be attached to the upper surface of the display panel (100) using a transparent adhesive member.

[0042] The cover window (CW) is made of a transparent material and may be glass or plastic. For example, if the cover window (CW) is glass, it may be ultra-thin glass (UTG) with a thickness of 0.1 mm or less. If the cover window (CW) is plastic, it may include a transparent polyimide film.

[0043] A fingerprint sensor (400) may be placed on the lower surface of the display panel (100). The fingerprint sensor (400) may be attached to the lower surface of the display panel (100) using a transparent adhesive member.

[0044] A fingerprint sensor (400) may include a fingerprint detection layer (410) comprising sensor pixels (SP) and a collimator layer (420) comprising openings (OA) and a light-blocking portion (LSA) disposed between the openings (OA). Each of the sensor pixels (SP) may overlap with a plurality of openings (OA) of the collimator layer (420) in a third direction (Z-axis direction).

[0045] Each of the openings (OA) of the collimator layer (420) may be a passage through which light reflected from the ridges (RID) and valleys (VAL) of the fingerprint of the finger (F) is incident. Specifically, when the user's finger (F) comes into contact with the cover window (CW), light output from the display panel (100) may be reflected from the ridges and valleys of the fingerprint of the finger (F). The light reflected from the finger (F) may be incident on the sensor pixels (SP) of the fingerprint detection layer (410) through the display panel (100) and the openings (OA) of the collimator layer (420).

[0046] The range (LR) of light incident on the sensor pixel (SP) through the openings (OA) of the collimator layer (420) may be shorter than the distance (FP) between the crest (RID) and valley (VAL) of the fingerprint of the finger (F). The distance (FP) between the crest (RID) and valley (VAL) of the fingerprint of the finger (F) may be approximately 500 μm. As a result, the detection current flowing through the light-sensing elements of each sensor pixel (SP) may differ depending on whether the light is reflected from the crest of the fingerprint of the finger (F) or from the valley of the fingerprint of the finger (F). Therefore, the detection voltages output from the sensor pixels (SP) may differ depending on whether the light is reflected from the crest of the fingerprint of the finger (F) or from the valley of the fingerprint of the finger (F). Accordingly, the fingerprint driving circuit (510) can recognize the fingerprint pattern of the finger (F) according to the detection voltages of the sensor pixels (SP).

[0047] Figure 4 is an enlarged cross-sectional view showing in detail an example of a display panel in area A of Figure 3.

[0048] Referring to FIG. 4, the display panel (100) may include display pixels (DP) for displaying an image. Each of the display pixels (DP) may include a first thin-film transistor (ST1) and a light-emitting element (170).

[0049] A first buffer film (BF1) may be disposed on a first substrate (SUB1), a second substrate (SUB2) may be disposed on the first buffer film (BF1), and a second buffer film (BF2) may be disposed on the second substrate (SUB2).

[0050] Each of the first substrate (SUB1) and the second substrate (SUB2) may be made of an insulating material such as a polymer resin. For example, the first substrate (SUB1) and the second substrate (SUB2) may include polyimide. Each of the first substrate (SUB1) and the second substrate (SUB2) may be a flexible substrate capable of bending, folding, rolling, etc.

[0051] Each of the first buffer film (BF1) and the second buffer film (BF2) is a film for protecting the thin film transistor of the thin film transistor layer (TFTL) and the light-emitting layer (172) of the light-emitting element layer (EML) from moisture penetrating through the first substrate (SUB1) and the second substrate (SUB2), which are vulnerable to moisture permeability. Each of the first buffer film (BF1) and the second buffer film (BF2) may be composed of a plurality of inorganic films that are alternately stacked. For example, each of the first buffer film (BF1) and the second buffer film (BF2) may be formed as a multilayer film in which one or more inorganic films among a silicon nitride layer, a silicon oxynitride layer, a silicon oxide layer, a titanium oxide layer, and an aluminum oxide layer are alternately stacked.

[0052] A light-blocking layer (BML) may be disposed on the second substrate (SUB2). The light-blocking layer (BML) may be disposed overlapping the first active layer (ACT1) of the first thin-film transistor (ST1) in a third direction (Z-axis direction) to prevent leakage current from occurring when light is incident on the first active layer (ACT1) of the first thin-film transistor (ST1). The light-blocking layer (BML) may be formed as a single layer or a multilayer composed of any one of molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), and copper (Cu), or an alloy thereof. The light-blocking layer (BML) may be omitted.

[0053] A first active layer (ACT1) of a first thin-film transistor (ST1) may be disposed on the second buffer film (BF2). The first active layer (ACT1) of the first thin-film transistor (ST1) comprises polycrystalline silicon, single-crystal silicon, low-temperature polycrystalline silicon, amorphous silicon, or an oxide semiconductor. The first active layer (ACT1) of the first thin-film transistor (ST1), which is exposed and not covered by the first gate insulating film (GI1), may have conductivity because it is doped with impurities or ions. Therefore, a first source electrode (S1) and a first drain electrode (D1) of the first active layer (ACT1) of the first thin-film transistor (ST1) may be formed.

[0054] A first gate insulating film (GI1) may be disposed on the first active layer (ACT1) of the first thin-film transistor (ST1). In FIG. 4, the first gate insulating film (GI1) is illustrated as being disposed between the first gate electrode (G1) and the first active layer (ACT1) of the first thin-film transistor (ST1), but is not limited thereto. The first gate insulating film (GI1) may also be disposed between the first interlayer insulating film (141) and the first active layer (ACT1), and between the first interlayer insulating film (141) and the second buffer film (BF2). The first gate insulating film (GI1) may be formed of an inorganic film, for example, a silicon nitride layer, a silicon oxynitride layer, a silicon oxide layer, a titanium oxide layer, or an aluminum oxide layer.

[0055] A first gate electrode (G1) of a first thin-film transistor (ST1) may be disposed on a first gate insulating film (GI1). The first gate electrode (G1) of the first thin-film transistor (ST1) may overlap with a first active layer (ACT1) in a third direction (Z-axis direction). The first gate electrode (G1) of the first thin-film transistor (ST1) may be formed as a single layer or a multilayer made of any one of molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), and copper (Cu), or an alloy thereof.

[0056] A first interlayer insulating film (141) may be disposed on the first gate electrode (G1) of the first thin-film transistor (ST1). The first interlayer insulating film (141) may be formed of an inorganic film, for example, a silicon nitride layer, a silicon oxynitride layer, a silicon oxide layer, a titanium oxide layer, or an aluminum oxide layer. The first interlayer insulating film (141) may include a plurality of inorganic films.

[0057] A first capacitor electrode (CAE1) may be disposed on the first interlayer insulating film (141). The first capacitor electrode (CAE1) may overlap with the first gate electrode (G1) of the first thin-film transistor (ST1) in the third direction (Z-axis direction). Since the first interlayer insulating film (141) has a predetermined dielectric constant, a capacitor may be formed by the first capacitor electrode (CAE1), the first gate electrode (G1), and the first interlayer insulating film (141) disposed between them. The first capacitor electrode (CAE1) may be formed as a single layer or a multilayer made of any one of molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), and copper (Cu), or an alloy thereof.

[0058] A second interlayer insulating film (142) may be disposed on the first capacitor electrode (CAE1). The second interlayer insulating film (142) may be formed of an inorganic film, for example, a silicon nitride layer, a silicon oxynitride layer, a silicon oxide layer, a titanium oxide layer, or an aluminum oxide layer. The second interlayer insulating film (142) may include a plurality of inorganic films.

[0059] A first anode connection electrode (ANDE1) may be disposed on the second interlayer insulating film (142). The first anode connection electrode (ANDE1) may be connected to the first drain electrode (D) of the first thin-film transistor (ST1) through a first anode contact hole (ANCT1) that penetrates the first interlayer insulating film (141) and the second interlayer insulating film (142) to expose the first drain electrode (D1) of the first thin-film transistor (ST1). The first anode connection electrode (ANDE1) may be formed as a single layer or a multilayer made of any one of molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), and copper (Cu), or an alloy thereof.

[0060] A first organic film (160) for planarization may be disposed on the first anode connecting electrode (ANDE1). The first organic film (160) may be formed from an organic film such as an acrylic resin, an epoxy resin, a phenolic resin, a polyamide resin, or a polyimide resin.

[0061] A second anode connecting electrode (ANDE2) may be disposed on the first organic film (160). The second anode connecting electrode (ANDE2) may be connected to the second anode connecting electrode (ANDE2) through a second anode contact hole (ANCT2) that penetrates the first organic film (160) and exposes the first anode connecting electrode (ANDE1). The second anode connecting electrode (ANDE2) may be formed as a single layer or a multilayer made of any one of molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), and copper (Cu), or an alloy thereof.

[0062] A second organic film (180) may be disposed on the second anode connecting electrode (ANDE2). The second organic film (180) may be formed from an organic film such as an acrylic resin, an epoxy resin, a phenolic resin, a polyamide resin, or a polyimide resin.

[0063] In FIG. 4, the first thin-film transistor (ST1) is exemplified as being formed in a top gate configuration where the first gate electrode (G1) is located on the upper side of the first active layer (ACT1), but it should be noted that this is not limited thereto. The first thin-film transistor (ST1) may be formed in a bottom gate configuration where the first gate electrode (G1) is located on the lower side of the first active layer (ACT1), or in a double gate configuration where the first gate electrode (G1) is located on both the upper and lower sides of the first active layer (ACT1).

[0064] Light-emitting elements (170) and a bank (190) may be disposed on the second organic film (180). Each of the light-emitting elements (170) includes a first light-emitting electrode (171), a light-emitting layer (172), and a second light-emitting electrode (173).

[0065] A first light-emitting electrode (171) may be formed on a second organic film (180). The first light-emitting electrode (171) may be connected to a second anode connecting electrode (ANDE2) through a third anode contact hole (ANCT3) that penetrates the second organic film (180) and exposes the second anode connecting electrode (ANDE2).

[0066] In a top emission structure that emits light in the direction of the second emission electrode (173) based on the emission layer (172), the first emission electrode (171) can be formed of a highly reflective metallic material such as a stacked structure of aluminum and titanium (Ti / Al / Ti), a stacked structure of aluminum and ITO (ITO / Al / ITO), an APC alloy, and a stacked structure of APC alloy and ITO (ITO / APC / ITO). The APC alloy is an alloy of silver (Ag), palladium (Pd), and copper (Cu).

[0067] A bank (190) may be formed to partition the first light-emitting electrode (171) on the second organic film (180) to serve to define a light-emitting region (EA). A bank (190) may be formed to cover the edge of the first light-emitting electrode (171). A bank (190) may be formed from an organic film such as an acrylic resin, an epoxy resin, a phenolic resin, a polyamide resin, or a polyimide resin.

[0068] The light-emitting region (EA) represents a region in which a first light-emitting electrode (171), a light-emitting layer (172), and a second light-emitting electrode (173) are sequentially stacked, and holes from the first light-emitting electrode (171) and electrons from the second light-emitting electrode (173) combine with each other in the light-emitting layer (172) to emit light.

[0069] A light-emitting layer (172) is formed on the first light-emitting electrode (171) and the bank (190). The light-emitting layer (172) may include an organic material and emit a predetermined color. For example, the light-emitting layer (172) includes a hole transporting layer, an organic material layer, and an electron transporting layer.

[0070] A second light-emitting electrode (173) is formed on the light-emitting layer (172). The second light-emitting electrode (173) may be formed to cover the light-emitting layer (172). The second light-emitting electrode (173) may be a common layer formed in common across all light-emitting regions (EA). A capping layer may be formed on the second light-emitting electrode (173).

[0071] In the upper light-emitting structure, the second light-emitting electrode (173) can be formed from a transparent conductive oxide (TCO, Transparent Conductive Oxide) such as Indium Tin Oxide (ITO) and Indium Zinc Oxide (IZO) that can transmit light, or a semi-transmissive conductive material such as magnesium (Mg), silver (Ag), or an alloy of magnesium (Mg) and silver (Ag). When the second light-emitting electrode (173) is formed from a semi-transmissive conductive material, the light emission efficiency can be increased by the micro cavity.

[0072] An encapsulation layer (TFE) may be disposed on the second light-emitting electrode (173). The encapsulation layer (TFE) includes at least one inorganic film to prevent oxygen or moisture from penetrating the light-emitting element layer (EML). Additionally, the encapsulation layer (TFE) includes at least one organic film to protect the light-emitting element layer (EML) from foreign substances such as dust. For example, the encapsulation layer (TFE) includes a first inorganic film (TFE1), an organic film (TFE2), and a second inorganic film (TFE3).

[0073] A first inorganic film (TFE1) may be disposed on a second light-emitting electrode (173), an organic film (TFE2) may be disposed on the first inorganic film (TFE1), and a second inorganic film (TFE3) may be disposed on the organic film (TFE2). The first inorganic film (TFE1) and the second inorganic film (TFE3) may be formed as a multilayer film in which one or more inorganic films selected from a silicon nitride layer, a silicon oxynitride layer, a silicon oxide layer, a titanium oxide layer, and an aluminum oxide layer are alternately stacked. The organic film (TFE2) may be a monomer.

[0074] Figure 5 is an enlarged cross-sectional view showing in detail an example of a fingerprint sensor in area A of Figure 3.

[0075] Referring to FIG. 5, the fingerprint sensor (400) may include a fingerprint detection layer (410) and a collimator layer (420) disposed on the fingerprint detection layer (410).

[0076] The fingerprint detection layer (410) may include sensor pixels (SP) that detect light. Each of the sensor pixels (SP) may include a second thin-film transistor (ST2) and a light-sensing element (PD).

[0077] A buffer film (BF) may be disposed on the fingerprint sensor substrate (FSUB). The fingerprint sensor substrate (FSUB) may be made of an insulating material such as a polymer resin. For example, the fingerprint sensor substrate (FSUB) may include polyimide. Each fingerprint sensor substrate (FSUB) may be a flexible substrate capable of bending, folding, rolling, etc.

[0078] The buffer film (BF) is a film for protecting the thin-film transistor and the photodetector (PD) of the fingerprint sensing layer (410) from moisture penetrating through the fingerprint sensor substrate (FSUB), which is susceptible to moisture permeability. The buffer film (BF) may be composed of a plurality of inorganic films that are alternately stacked. For example, the buffer film (BF) may be formed as a multilayer film in which one or more inorganic films among a silicon nitride layer, a silicon oxynitride layer, a silicon oxide layer, a titanium oxide layer, and an aluminum oxide layer are alternately stacked.

[0079] A second active layer (ACT2) of a second thin-film transistor (ST2) may be disposed on the buffer film (BF). The second active layer (ACT2) of the second thin-film transistor (ST2) comprises polycrystalline silicon, single-crystal silicon, low-temperature polycrystalline silicon, amorphous silicon, or an oxide semiconductor. The second active layer (ACT2) of the second thin-film transistor (ST2), which is exposed and not covered by the second gate insulating film (GI2), may be conductive as it is doped with impurities or ions. Therefore, a second source electrode (S2) and a second drain electrode (D2) of the second active layer (ACT2) of the second thin-film transistor (ST2) may be formed.

[0080] A second gate insulating film (GI2) may be disposed on the second active layer (ACT2) of the second thin-film transistor (ST2). In FIG. 5, the second gate insulating film (GI2) is exemplified as being disposed between the second gate electrode (G2) of the second thin-film transistor (ST2) and the second active layer (ACT2), and between the first fingerprint capacitor electrode (FCE1) and the buffer film (BF), but is not limited thereto. The second gate insulating film (GI2) may also be disposed between the first insulating film (INS1) and the second active layer (ACT2), and between the first insulating film (INS1) and the buffer film (BF). The second gate insulating film (GI2) may be formed of an inorganic film, for example, a silicon nitride layer, a silicon oxynitride layer, a silicon oxide layer, a titanium oxide layer, or an aluminum oxide layer.

[0081] The second gate electrode (G2) of the second thin-film transistor (ST2) and the first fingerprint capacitor electrode (FCE1) may be disposed on the second gate insulating film (GI2). The second gate electrode (G2) of the second thin-film transistor (ST2) may overlap with the second active layer (ACT2) in the third direction (Z-axis direction). The second gate electrode (G2) of the second thin-film transistor (ST2) and the first fingerprint capacitor electrode (FCE1) may be formed as a single layer or a multilayer made of any one of molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), and copper (Cu), or an alloy thereof.

[0082] A first insulating film (INS1) may be disposed on the second gate electrode (G2) and the first fingerprint capacitor electrode (FCE1) of the second thin-film transistor (ST2). The first insulating film (INS1) may be formed of an inorganic film, for example, a silicon nitride layer, a silicon oxynitride layer, a silicon oxide layer, a titanium oxide layer, or an aluminum oxide layer. The first insulating film (INS1) may include a plurality of inorganic films.

[0083] A light-sensing element (PD) and a second fingerprint capacitor electrode (FCE2) may be disposed on the first insulating film (INS1). The second fingerprint capacitor electrode (PCE2) may overlap with the first fingerprint capacitor electrode (PCE1) in a third direction (Z-axis direction). Since the first insulating film (INS1) has a predetermined dielectric constant, a capacitor may be formed by the first fingerprint capacitor electrode (FCE1), the second fingerprint capacitor electrode (PCE2), and the first insulating film (INS1) disposed between them.

[0084] The light-sensing element (PD) may be formed as a photodiode as shown in FIG. 5, but is not limited thereto. The light-sensing element (PD) may be formed as a phototransistor. The light-sensing element (PD) may include a first sensing electrode (PCE), a sensing semiconductor layer (PSEM), and a second sensing electrode (PAE). The first sensing electrode (PCE) may be a cathode electrode, and the second sensing electrode (PAE) may be an anode electrode.

[0085] The first sensing electrode (PCE) may be disposed on the first insulating film (INS1). The first sensing electrode (PCE) may be formed of the same material as the second fingerprint capacitor electrode (PCE2). The first sensing electrode (PCE) and the second fingerprint capacitor electrode (PCE2) may be formed as a single layer of molybdenum (Mo), titanium (Ti), copper (Cu), or aluminum (Al), or as a stacked structure of aluminum and titanium (Ti / Al / Ti), a stacked structure of aluminum and ITO (ITO / Al / ITO), an APC alloy, and a stacked structure of APC alloy and ITO (ITO / APC / ITO).

[0086] A photodetector layer (PSEM) may be disposed on the first sensing electrode (PCE). The photodetector layer (PSEM) may be formed in a PIN structure in which a P-type semiconductor layer (PL), an I-type semiconductor layer (IL), and an N-type semiconductor layer (NL) are stacked in sequence. When the photodetector layer (PSEM) is formed in a PIN structure, the I-type semiconductor layer (IL) becomes depleted by the P-type semiconductor layer (PL) and the N-type semiconductor layer (NL), causing an electric field to be generated internally, and holes and electrons generated by sunlight drift due to the electric field. As a result, holes can be collected to the second sensing electrode (PAE) through the P-type semiconductor layer (PL), and electrons can be collected to the first sensing electrode (PCE) through the N-type semiconductor layer (NL).

[0087] The P-type semiconductor layer (PL) can be positioned close to the surface where external light is incident, and the N-type semiconductor layer (NL) can be positioned far from the surface where external light is incident. Since the drift mobility of holes is lower than that of electrons, it is desirable to form the P-type semiconductor layer (PL) close to the surface where external light is incident in order to maximize the collection efficiency of the incident light.

[0088] An N-type semiconductor layer (NL) may be disposed on a first sensing electrode (PCE), an I-type semiconductor layer (IL) may be disposed on the N-type semiconductor layer (NL), and a P-type semiconductor layer (PL) may be disposed on the I-type semiconductor layer (IL). In this case, the P-type semiconductor layer (PL) may be formed by doping a P-type dopant into amorphous silicon (a-Si:H). The I-type semiconductor layer (IL) may be formed of amorphous silicon germanium (a-SiGe:H) or amorphous silicon carbide (a-SiC:H). The N-type semiconductor layer (NL) may be formed by doping an N-type dopant into amorphous silicon germanium (a-SiGe:H) or amorphous silicon carbide (a-SiC:H). The P-type semiconductor layer (PL) and the N-type semiconductor layer (NL) are formed with a thickness of approximately 500 Å, and the I-type semiconductor layer (IL) can be formed with a thickness of 5,000 Å to 10,000 Å.

[0089] Alternatively, the N-type semiconductor layer (NL) may be disposed on the first sensing electrode (PCE), the I-type semiconductor layer (IL) may be omitted, and the P-type semiconductor layer (PL) may be disposed on the N-type semiconductor layer (NL). In this case, the P-type semiconductor layer (PL) may be formed by doping a P-type dopant into amorphous silicon (a-Si:H). The N-type semiconductor layer (NL) may be formed by doping an N-type dopant into amorphous silicon germanium (a-SiGe:H) or amorphous silicon carbide (a-SiC:H). The P-type semiconductor layer (PL) and the N-type semiconductor layer (NL) may be formed with a thickness of 500 Å.

[0090] In addition, the upper or lower surface of at least one of the first sensing electrode (PCE), the P-type semiconductor layer (PL), the I-type semiconductor layer (IL), the N-type semiconductor layer (NL), and the second sensing electrode (PAE) can be formed into an uneven structure through a texturing process to increase the absorption rate of external light. The texturing process is a process of forming a material surface into a rough, uneven structure, and processing it into a shape similar to the surface of a fabric. The texturing process can be performed through an etching process using photolithography, an anisotropic etching process using a chemical solution, or a groove formation process using mechanical scribing.

[0091] The second sensing electrode (PAE) can be placed on a P-type semiconductor layer (PL). The second sensing electrode (PAE) can be formed of a transparent conductive material (TCO), such as Indium Tin Oxide (ITO) and Indium Zinc Oxide (IZO), which can transmit light.

[0092] A second insulating film (INS2) may be disposed on the light sensing element (PD) and the second fingerprint capacitor electrode (FCE2). The second insulating film (INS2) may be formed of an inorganic film, for example, a silicon nitride layer, a silicon oxynitride layer, a silicon oxide layer, a titanium oxide layer, or an aluminum oxide layer. The second insulating film (INS2) may include a plurality of inorganic films.

[0093] A first connecting electrode (CE1), a second connecting electrode (CE2), and a third connecting electrode (CE3) may be disposed on the second insulating film (INS2).

[0094] The first connection electrode (CE1) can be connected to the second source electrode (S2) of the second thin-film transistor (ST2) through a source contact hole (SCT) that penetrates the first insulating film (INS1) and the second insulating film (INS2) to expose the second source electrode (S2) of the second thin-film transistor (ST2).

[0095] The second connecting electrode (CE2) can be connected to the second drain electrode (D2) of the second thin-film transistor (ST2) through a drain contact hole (DCT) that penetrates the first insulating film (INS1) and the second insulating film (INS2) to expose the second drain electrode (D2) of the second thin-film transistor (ST2). The second connecting electrode (CE2) can be connected to the first sensing electrode (PCE) through a first sensing contact hole (RCT1) that penetrates the second insulating film (INS2) to expose the first sensing electrode (PCE). As a result, the drain electrode (D2) of the second thin-film transistor (ST2) and the first sensing electrode (PCE) of the photo-sensing element (PD) can be connected by the second connecting electrode (CE2).

[0096] The third connecting electrode (CE3) can be connected to the second sensing electrode (PAE) through a second sensing contact hole (RCT2) that penetrates the second insulating film (INS2) and exposes the second sensing electrode (PAE).

[0097] The first connecting electrode (CE1), the second connecting electrode (CE2), and the third connecting electrode (CE3) may be formed as a single layer or multiple layers made of any one of molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), and copper (Cu), or an alloy thereof.

[0098] A third insulating film (INS3) may be disposed on the first connecting electrode (CE1), the second connecting electrode (CE2), and the third connecting electrode (CE3). The third insulating film (INS3) may be formed of an inorganic film, for example, a silicon nitride layer, a silicon oxynitride layer, a silicon oxide layer, a titanium oxide layer, or an aluminum oxide layer. The third insulating film (INS3) may include a plurality of inorganic films. The third insulating film (INS3) may be omitted.

[0099] A planarization film (PLA) may be disposed on the third insulating film (INS3). The planarization film (PLA) may be formed from an organic film such as an acrylic resin, an epoxy resin, a phenolic resin, a polyamide resin, or a polyimide resin.

[0100] The collimator layer (420) may include first light-transmitting films (LT1), second light-transmitting films (LT2), and a light-blocking film (LS).

[0101] First light-transmitting films (LT1) may be placed on a flattening film (PLA) of a light-sensing layer (410). The first light-transmitting films (LT1) may be spaced apart from each other. The first light-transmitting films (LT1) may be placed in a first direction (X-axis direction) at a first interval and in a second direction (Y-axis direction) at a second interval. The first interval and the second interval may be substantially the same, but are not limited thereto. For example, the first light-transmitting films (LT1) may be placed approximately every 4 μm in the first direction (X-axis direction) and the second direction (Y-axis direction), but are not limited thereto.

[0102] The width of the first light-transmitting film (LT1) may be approximately 1 μm to 2 μm, but is not limited thereto. The width of the first light-transmitting film (LT1) may be the length in the first direction (X-axis direction) or the second direction (Y-axis direction) of the first light-transmitting film (LT1). The length in the third direction (Z-axis direction) of the first light-transmitting film (LT1) may be several μm. For example, the length in the third direction (Z-axis direction) of the first light-transmitting film (LT1) may be 5 μm or more. The first light-transmitting film (LT1) may have a polygonal column shape such as a cylinder, an elliptical column, or a square column.

[0103] The first light-transmitting film (LT1) can be formed from an organic film such as an acrylic resin, an epoxy resin, a phenolic resin, a polyamide resin, or a polyimide resin.

[0104] A second light-transmitting film (LT2) may be disposed on the first light-transmitting films (LT1). The second light-transmitting film (LT2) may be disposed on the upper surface and sides of each of the first light-transmitting films (LT1). The second light-transmitting film (LT2) may be disposed on a flattening film (PLA) between the first light-transmitting films (LT1).

[0105] The second light-transmitting film (LT2) may be formed of a material different from the first light-transmitting film (LT1). The second light-transmitting film (LT2) may have substantially the same refractive index as the first light-transmitting film (LT1). Alternatively, the second light-transmitting film (LT2) may have a lower refractive index than the first light-transmitting film (LT1). The second light-transmitting film (LT2) may be formed of an inorganic film. To make the refractive index of the second light-transmitting film (LT2) substantially the same as or lower than the refractive index of the first light-transmitting film (LT1), the second light-transmitting film (LT2) may be formed of a silicon oxynitride layer or a silicon oxide layer.

[0106] A light-blocking film (LS) may be placed between first light-transmitting films (LT1). The light-blocking film (LS) may be placed between one first light-transmitting film (LT1) and another first light-transmitting film (LT1) among the first light-transmitting films (LT1) that are adjacent to each other in a first direction (X-axis direction). Additionally, the light-blocking film (LS) may be placed between one first light-transmitting film (LT1) and another first light-transmitting film (LT1) among the first light-transmitting films (LT1) that are adjacent to each other in a second direction (Y-axis direction).

[0107] Since the second light-transmitting film (LT2) is disposed on each side of the first light-transmitting films (LT1), the sides of the light-blocking film (LS) can be surrounded by the second light-transmitting film (LT2). Additionally, the second light-transmitting film (LT2) can be disposed on the lower surface of the light-blocking film (LS). The upper surface of the second light-transmitting film (LT2) and the upper surface of the light-blocking film (LS) can be flat.

[0108] The width of the shading film (LS) may be approximately 1 μm to 1.5 μm, but is not limited thereto. The width of the shading film (LS) may be the length in the first direction (X-axis direction) or the length in the second direction (Y-axis direction) of the shading film (LS).

[0109] The width of the second light-transmitting film (LT2) may be approximately 0.5 μm to 1 μm or less, but is not limited thereto. The width of the second light-transmitting film (LT2) may be the length in the first direction (X-axis direction) or the length in the second direction (Y-axis direction) of the second light-transmitting film (LT2) disposed between the first light-transmitting film (LT1) and the light-blocking film (LS).

[0110] The light-blocking film (LS) can be formed from a photosensitive resin capable of blocking light. For example, the light-blocking film (LS) may include an inorganic black pigment such as carbon black or an organic black pigment.

[0111] Each of the openings (OA) of the collimator layer (420) is defined as an area where a light-blocking film (LS) is not placed, and the light-blocking area (LSA) can be defined as an area where a light-blocking film (LS) is placed. A first light-transmitting film (LT1) and a second light-transmitting film (LT2) are placed in each of the openings (OA). Since the light-sensing element (PD) overlaps with a plurality of openings (OA) in a third direction (Z-axis direction), light can be incident on the light-sensing element (PD) of the sensor pixel (SP) through the openings (OA).

[0112] A transparent adhesive member (430) may be disposed on the collimator layer (420). The transparent adhesive member (430) may be attached to the upper surface of the collimator layer (420) and the lower surface of the display panel (100). The refractive index of the transparent adhesive member (430) may be higher than the refractive index of the first light-transmitting film (LT1).

[0113] FIGS. 6 to 8 are example drawings showing the light propagation path according to the refractive index of the first light-transmitting film and the refractive index of the second light-transmitting film in FIG. 5.

[0114] FIG. 6 shows the path of light incident on the opening (OA) of the collimator layer (420) when the refractive index of the first light-transmitting film (LT1) is substantially the same as the refractive index of the second light-transmitting film (LT2). FIG. 7 shows the path of light incident on the opening (OA) of the collimator layer (420) when the refractive index of the first light-transmitting film (LT1) is higher than the refractive index of the second light-transmitting film (LT2). FIG. 8 shows the path of light incident on the opening (OA) of the collimator layer (420) when the refractive index of the first light-transmitting film (LT1) is lower than the refractive index of the second light-transmitting film (LT2).

[0115] Referring to FIG. 6, when the refractive index of the first light-transmitting film (LT1) is substantially the same as the refractive index of the second light-transmitting film (LT2), light incident on the aperture (OA) can be incident on the light-sensing element (PD) of the light-sensing layer (410) without being refracted. Light incident on the aperture (OA) can pass through the aperture (OA) if the angle of the light is less than or equal to the first angle (θ1). The angle of the light incident on the aperture (OA) refers to the angle at which the light incident on the aperture (OA) is inclined from the normal (VL) drawn perpendicularly to the upper surface of the aperture (OA). Therefore, noise light passing through the aperture (OA) and incident on the light-sensing element (PD) can be minimized.

[0116] Referring to FIG. 7, when the refractive index of the first light-transmitting film (LT1) is higher than the refractive index of the second light-transmitting film (LT2), light incident on the opening (OA) can be refracted at the boundary between the transparent adhesive member (430) and the second light-transmitting film (LT2), and at the boundary between the first light-transmitting film (LT1) and the second light-transmitting film (LT2). For example, when the angle of light incident on the opening (OA) is a second angle (θ2) which is greater than the first angle (θ1), the light can be refracted at the boundary between the transparent adhesive member (430) and the second light-transmitting film (LT2), at the boundary between the second light-transmitting film (LT2) and the first light-transmitting film (LT1), and at the boundary between the first light-transmitting film (LT1) and the second light-transmitting film (LT2). As a result, light incident on the aperture (OA) at a second angle (θ2) can pass through the aperture (OA). Therefore, in the embodiment of FIG. 7, the amount of light passing through the aperture (OA) and incident on the light-sensing element (PD) can be increased compared to the embodiment of FIG. 6.

[0117] Referring to FIG. 8, when the refractive index of the first light-transmitting film (LT1) and the refractive index of the transparent adhesive member (430) are lower than the refractive index of the second light-transmitting film (LT2), light incident on the opening (OA) can be refracted at the boundary between the transparent adhesive member (430) and the second light-transmitting film (LT2), and at the boundary between the first light-transmitting film (LT1) and the second light-transmitting film (LT2). For example, when the angle of light incident on the opening (OA) is the first angle (θ1), the light can be refracted at the boundary between the transparent adhesive member (430) and the second light-transmitting film (LT2), at the boundary between the second light-transmitting film (LT2) and the first light-transmitting film (LT1), and at the boundary between the first light-transmitting film (LT1) and the second light-transmitting film (LT2). As a result, light incident on the opening (OA) at the first angle (θ1) may not be able to pass through the opening (OA).

[0118] In summary, when the refractive index of the first light-transmitting film (LT1) is substantially the same as the refractive index of the second light-transmitting film (LT2), the amount of light that can be detected as noise among the light incident on the light-sensing element (PD) can be minimized. Therefore, the accuracy of fingerprint recognition of the finger (F) can be increased. In addition, when the refractive index of the first light-transmitting film (LT1) is lower than the refractive index of the second light-transmitting film (LT2), the amount of light passing through the aperture (OA) and incident on the light-sensing element (PD) can be increased.

[0119] Figure 9 is a graph showing the light transmittance of the aperture according to the angle of incidence of light, according to the refractive index of the second light-transmitting film.

[0120] In FIG. 9, the x-axis indicates the angle of incidence, and the y-axis indicates the light transmittance of the aperture (OA). The angle of incidence indicates the angle of light incident on the aperture (OA). The light transmittance of the aperture (OA) indicates the ratio of light passing through the aperture (OA) to the light incident on the aperture (OA).

[0121] In FIG. 9, the first curve (C1) illustrates a case where the width of the first light-transmitting film (LT1) is 2 μm, the second light-transmitting film (LT2) is omitted, and the width of the light-blocking film (LS) is 2 μm. The second to fifth curves (C2 to C5) illustrate cases where the width of the first light-transmitting film (LT1) is 2 μm, the width of the second light-transmitting film (LT2) is 1 μm, and the width of the light-blocking film (LS) is 1 μm. Each of the first to fifth curves (C1 to C5) illustrates a case where the refractive index of the first light-transmitting film (LT1) is 1.5. In the second curve (C2), the refractive index of the second light-transmitting film (LT2) is 1.5, and in the third curve (C3), the refractive index of the second light-transmitting film (LT2) may be 1.4. In the fourth curve (C4), the refractive index of the second light-transmitting film (LT2) is 1.6, and in the fifth curve (C5), the refractive index of the second light-transmitting film (LT2) may be 1.7.

[0122] Referring to FIG. 9, in the case of the first curve (C1), light with an incident angle of approximately 13 degrees or less can pass through the aperture (OA). Additionally, in the case of the first curve (C1), the transmittance of light at an incident angle of 0 degrees can be 20% or less.

[0123] In the case of the second curve (C2), the light transmittance is 43% at an incident angle of 0 degrees, and the light transmittance can be 10% or more at an incident angle of 0 to 13 degrees. Therefore, in the case of the second curve (C2), the light transmittance of the aperture (OA) can be increased compared to the first curve (C1). In addition, in the second curve (C2), only light with an incident angle of approximately 17 degrees or less passes through the aperture (OA), so the increase in noise light incident on the light detection element (PD) can be minimized.

[0124] In the case of the third curve (C3), the light transmittance is 43% at an incident angle of 0 degrees, and the light transmittance can be 20% or more at an incident angle of 0 to 17 degrees. Therefore, in the case of the third curve (C3), the light transmittance of the aperture (OA) can be increased compared to the second curve (C2). However, in the case of the third curve (C3), the light transmittance is 5% at an incident angle of 20 degrees, so the incident angle of light passing through the aperture (OA) can be increased compared to the second curve (C2).

[0125] In the case of the fourth curve (C4), since the light transmittance is 10% or more at an incident angle of 25 degrees, the noise light incident on the light detection element (PD) may increase.

[0126] In the case of the fifth curve (C5), since the light transmittance is 25% or more at an incident angle of 25 degrees, the noise light incident on the light sensing element (PD) may increase.

[0127] In summary, as shown in the second curve (C2), even if the width of the aperture (OA) is made longer than the width of the light-blocking portion (LSA), if the refractive index of the first light-transmitting film (LT1) and the refractive index of the second light-transmitting film (LT2) are made substantially the same, not only is the light transmittance of the aperture (OA) increased, but the increase in noise light incident on the light-sensing element (PD) can also be minimized.

[0128] In addition, as in the third curve (C3), if the width of the opening (OA) is made longer than the width of the light-blocking part (LSA) and the refractive index of the first light-transmitting film (LT1) is greater than the refractive index of the second light-transmitting film (LT2), the light transmittance of the opening (OA) can be increased.

[0129] FIG. 10 is an enlarged cross-sectional view showing in detail another example of a fingerprint sensor in area A of FIG. 3.

[0130] The embodiment of FIG. 10 differs from the embodiment of FIG. 5 in that a third light-transmitting film (LT3) is additionally disposed between the upper surface of the first light-transmitting film (LT1) and the second light-transmitting film (LT2). FIG. 10 will be explained mainly in terms of the differences from the embodiment of FIG. 5.

[0131] Referring to FIG. 10, a third light-transmitting film (LT3) may be disposed on a first light-transmitting film (LT1). The third light-transmitting film (LT3) may be formed of a material different from that of the first light-transmitting film (LT1) and the second light-transmitting film (LT2). The third light-transmitting film (LT3) may be an organic film or an inorganic film. For example, if the third light-transmitting film (LT3) is an organic film, it may be a photoresist. If the third light-transmitting film (LT3) is an inorganic film, it may be a transparent conductive oxide (TCO). For example, if the third light-transmitting film (LT3) is an inorganic film, it may be ITO (Indium Tin Oxide) or IZO (Indium Zinc Oxide).

[0132] The refractive index of the third light-transmitting film (LT3) may have substantially the same refractive index as the first light-transmitting film (LT1). In this case, as described in conjunction with FIGS. 6 and 9, noise light passing through the aperture (OA) and incident on the light-sensing element (PD) can be minimized.

[0133] Alternatively, the refractive index of the third light-transmitting film (LT3) may be lower than that of the first light-transmitting film (LT1). In this case, as described in conjunction with FIGS. 7 and 9, the amount of light incident on the light-sensing element (PD) through the aperture (OA) may increase.

[0134] FIG. 11 is an enlarged cross-sectional view showing in detail another example of a fingerprint sensor in area A of FIG. 3.

[0135] The embodiment of FIG. 11 differs from the embodiment of FIG. 5 in that a color filter (CF) is placed on the second light-transmitting film (LT2) and the light-blocking film (LS). FIG. 11 will be explained mainly in terms of the differences from the embodiment of FIG. 5.

[0136] Referring to FIG. 11, the color filter (CF) can pass light of a specific wavelength band. For example, the color filter (CF) may be a green color filter that passes light of a wavelength band of 490 nm to 570 nm corresponding to green light. Alternatively, the color filter (CF) may be a cyan color filter that passes light of a wavelength band of 490 nm to 570 nm and a wavelength band of 450 nm to 480 nm corresponding to blue light.

[0137] Since the light output from the display panel (100) does not contain infrared light, the infrared light corresponds to external noise light. Therefore, it is necessary to block the infrared light. When a color filter (CF), such as a green color filter or a cyan color filter, is placed on the second light-transmitting film (LT2) and the light-blocking film (LS), the infrared light cannot pass through the color filter (CF), so the infrared light incident on the light-sensing element (PD) can be blocked.

[0138] FIG. 12 is an enlarged cross-sectional view showing in detail another example of a fingerprint sensor in area A of FIG. 3.

[0139] The embodiment of FIG. 12 differs from the embodiment of FIG. 5 in that the length (L2) of the third direction (Z-axis direction) of the light-blocking film (LS) is smaller than the length (L1) of the third direction (Z-axis direction) of the first light-transmitting film (LT1). FIG. 12 will be explained mainly in terms of the differences from the embodiment of FIG. 5.

[0140] Referring to FIG. 12, when the length (L2) of the third direction (Z-axis direction) of the light-blocking film (LS) is smaller than the length (L1) of the third direction (Z-axis direction) of the first light-transmitting film (LT1), a transparent adhesive member (430) may be placed on the upper surface of the light-blocking film (LS) and on the sides of the second light-transmitting film (LT2). When the refractive index of the first light-transmitting film (LT1) is substantially the same as the refractive index of the second light-transmitting film (LT2) or the refractive index of the first light-transmitting film (LT1) is greater than the refractive index of the second light-transmitting film (LT2), the refractive index of the transparent adhesive member (430) may be greater than the refractive index of the second light-transmitting film (LT2). As a result, the angle of refraction of light incident on the sides of the second light-transmitting film (LT2) may be greater than the angle of incidence. For example, as shown in FIG. 12, light incident on the aperture (OA) at a second angle (θ2) greater than the first angle (θ1) may not pass through the aperture (OA). Therefore, among the light incident on the light-sensing element (PD), light that can be detected as noise can be minimized.

[0141] FIG. 13 is an enlarged cross-sectional view showing in detail another example of a fingerprint sensor in area A of FIG. 3.

[0142] The embodiment of FIG. 13 differs from the embodiment of FIG. 12 in that a third light-transmitting film (LT3) is additionally disposed between the upper surface of the first light-transmitting film (LT1) and the second light-transmitting film (LT2). FIG. 13 will be explained mainly in terms of the differences from the embodiment of FIG. 12.

[0143] Referring to FIG. 13, a third light-transmitting film (LT3) may be disposed on a first light-transmitting film (LT1). The third light-transmitting film (LT3) may be formed of a material different from that of the first light-transmitting film (LT1) and the second light-transmitting film (LT2). The third light-transmitting film (LT3) may be an organic film or an inorganic film. For example, if the third light-transmitting film (LT3) is an organic film, it may be a photoresist. If the third light-transmitting film (LT3) is an inorganic film, it may be a transparent conductive oxide (TCO). For example, if the third light-transmitting film (LT3) is an inorganic film, it may be ITO (Indium Tin Oxide) or IZO (Indium Zinc Oxide).

[0144] The refractive index of the third light-transmitting film (LT3) may have substantially the same refractive index as the first light-transmitting film (LT1). In this case, as described in conjunction with FIGS. 6 and 9, noise light passing through the aperture (OA) and incident on the light-sensing element (PD) can be minimized.

[0145] Alternatively, the refractive index of the third light-transmitting film (LT3) may be lower than that of the first light-transmitting film (LT1). In this case, as described in conjunction with FIGS. 7 and 9, the amount of light incident on the light-sensing element (PD) through the aperture (OA) may increase.

[0146] FIG. 14 is an enlarged cross-sectional view showing in detail another example of a fingerprint sensor in area A of FIG. 3.

[0147] The embodiment of FIG. 14 differs from the embodiment of FIG. 12 in that a color filter (CF) is placed on the second light-transmitting film (LT2) and the light-blocking film (LS). FIG. 14 will be explained mainly in terms of the differences from the embodiment of FIG. 12.

[0148] Referring to FIG. 14, the color filter (CF) can pass light of a specific wavelength band. For example, the color filter (CF) may be a green color filter that passes light of a wavelength band of 490 nm to 570 nm corresponding to green light. Alternatively, the color filter (CF) may be a cyan color filter that passes light of a wavelength band of 490 nm to 570 nm and a wavelength band of 450 nm to 480 nm corresponding to blue light.

[0149] Since the light output from the display panel (100) does not contain infrared light, the infrared light corresponds to external noise light. Therefore, it is necessary to block the infrared light. When a color filter (CF), such as a green color filter or a cyan color filter, is placed on the second light-transmitting film (LT2) and the light-blocking film (LS), the infrared light cannot pass through the color filter (CF), so the infrared light incident on the light-sensing element (PD) can be blocked.

[0150] FIG. 15 is a flowchart showing a method for manufacturing a fingerprint sensor according to one embodiment. FIGS. 16 to 21 are exemplary drawings for explaining the method for manufacturing a fingerprint sensor of FIG. 15.

[0151] Hereinafter, a method for manufacturing a fingerprint sensor according to one embodiment will be described in detail in conjunction with FIGS. 16 to 21.

[0152] First, a light sensing layer (410) including a second thin-film transistor (ST2) and a light sensing element (PD) is formed. (S110 of FIG. 13)

[0153] Referring to FIG. 16, an inorganic material is deposited on a fingerprint sensor substrate (FSUB) to form a buffer film (BF).

[0154] A second active layer (ACT2) of a second thin-film transistor (ST2) is formed on a buffer film (BF) using a photolithography process.

[0155] An inorganic material is deposited on the second active layer (ACT2) of the second thin-film transistor (ST2) to form a second gate insulating film (GI2).

[0156] The second gate electrode (G2) of the second thin-film transistor (ST2) and the first fingerprint capacitor electrode (FCE1) are formed on the second gate insulating film (GI2) using a photolithography process. At this time, since the second gate insulating film (GI2) is etched using the second gate electrode (G2) of the second thin-film transistor (ST2) as a mask, the second gate insulating film (GI2) can be positioned between the second gate electrode (G2) of the second thin-film transistor (ST2) and the second active layer (ACT2), and between the first fingerprint capacitor electrode (FCE1) and the buffer film (BF). Additionally, the second active layer (ACT2) of the second thin-film transistor (ST2), which is exposed and not covered by the second gate insulating film (GI2), can have conductivity because it is doped with impurities or ions. Therefore, the second source electrode (S2) and the second drain electrode (D2) of the second thin-film transistor (ST2), which have conductivity, can be formed.

[0157] An inorganic material is deposited on the second gate electrode (G2), second source electrode (S2), and second drain electrode (D2) of the second thin-film transistor (ST2), and on the first fingerprint capacitor electrode (FCE1) to form a first insulating film (INS1).

[0158] A first sensing electrode (PCE) and a second fingerprint capacitor electrode (FCE2) of a photo-sensing element (PD) are formed on the first insulating film (INS1) using a photolithography process. A sensing semiconductor layer (PSEM) and a second sensing electrode (PAE) are formed on the first sensing electrode (PCE) using a photolithography process.

[0159] An inorganic material is deposited on the light-sensing element (PD) and the second fingerprint capacitor electrode (FCE2) to form a second insulating film (INS2).

[0160] In the second insulating film (INS2), a source contact hole (SCT), a drain contact hole (DCT), a first sensing contact hole (RCT1), and a second sensing contact hole (RCT2) are formed by a photolithography process. The source contact hole (SCT) and the drain contact hole (DCT) can be formed by removing the first insulating film (INS1) and the second insulating film (INS2). The first sensing contact hole (RCT1) and the second sensing contact hole (RCT2) can be formed by removing the second insulating film (INS2).

[0161] A first connecting electrode (CE1), a second connecting electrode (CE2), and a third connecting electrode (CE3) are formed on the second insulating film (INS2) by a photolithography process. The first connecting electrode (CE1) can be connected to the second source electrode (S2) of the second thin-film transistor (ST2) through a source contact hole (SCT). The second connecting electrode (CE2) can be connected to the second drain electrode (D2) of the second thin-film transistor (ST2) through a drain contact hole (DCT) and to the first sensing electrode (PCE) through a first sensing contact hole (RCT1). The third connecting electrode (CE3) can be connected to the second sensing electrode (PAE) through a second sensing contact hole (RCT2).

[0162] An inorganic material is deposited on the first connecting electrode (CE1), the second connecting electrode (CE2), and the third connecting electrode (CE3) to form a third insulating film (INS3). The third insulating film (INS3) may be omitted.

[0163] An organic material is deposited on the third insulating layer (INS3) to form a planarization film (PLA).

[0164] Secondly, a light-transmitting layer (LT) is formed on the light-sensing layer (410), and mask patterns (MS) are formed on the light-transmitting layer (LT). (S120 of FIG. 15)

[0165] Referring to FIG. 17, an organic material is deposited on a light-sensing layer (410) to form a light-transmitting layer (LT). The length of the light-transmitting layer (LT) in the third direction (Z-axis direction) may be several μm. For example, the length of the light-transmitting layer (LT) in the third direction (Z-axis direction) may be 5 μm or more. The light-transmitting layer (LT) may be an organic film such as an acrylic resin, an epoxy resin, a phenolic resin, a polyamide resin, or a polyimide resin.

[0166] Mask patterns (MS) are formed by depositing an organic or inorganic material on a light-transmitting layer (LT). The mask patterns (MS) may be spaced apart from each other. The mask patterns (MS) may be arranged in a first direction (X-axis direction) at a first interval and in a second direction (Y-axis direction) at a second interval. The first interval and the second interval may be substantially the same.

[0167] Mask patterns (MS) can be organic films such as photoresist. Alternatively, mask patterns (MS) can be inorganic films such as transparent conductive oxides (TCOs) like Indium Tin Oxide (ITO) or Indium Zinc Oxide (IZO), and aluminum (Al).

[0168] Third, the light-transmitting layer (LT) is etched to form first light-transmitting films (LT1). (S130 of FIG. 15)

[0169] Referring to FIG. 18, a light-transmitting layer (LT) not covered by mask patterns (MS) is dry-etched to form first light-transmitting films (LT1). The first light-transmitting films (LT1) may be spaced apart from each other. The first light-transmitting films (LT1) may be spaced apart in a first direction (X-axis direction) and spaced apart in a second direction (Y-axis direction). The first and second spacings may be substantially the same.

[0170] Fourth, the mask patterns (MS) are removed by a stripping process or an etching process as shown in FIG. 19. (S140 in FIG. 15)

[0171] Fifth, a second light-transmitting film (LT2) is formed on the first light-transmitting films (LT1). (S150 of FIG. 15)

[0172] Referring to FIG. 20, an inorganic material is deposited on the first light-transmitting films (LT1) to form a second light-transmitting film (LT2). The second light-transmitting film (LT2) can be formed on the upper surface and side surfaces of each of the first light-transmitting films (LT1). Additionally, it can be formed on the planarization film (PLA) of the light-sensing layer (410) between the first light-transmitting films (LT1). Because the second light-transmitting film (LT2) has good step coverage, it can be continuously connected without interruption.

[0173] Meanwhile, since the length of the third direction (Z-axis direction) of the first light-transmitting film (LT1) is long, the width of the first light-transmitting film (LT1) may be shorter than the width of the mask pattern (MS) due to over-etching. As the width of the first light-transmitting film (LT1) narrows, the width of the light-blocking film (LS) widens, so the light transmittance of the aperture (OA) may be lowered. Therefore, it is necessary to compensate for the reduction in the width of the first light-transmitting film (LT1), and accordingly, a second light-transmitting film (LT2) is formed.

[0174] Sixth, a light-blocking film (LS) is formed between the first light-transmitting films (LT1). (S160 in FIG. 15)

[0175] Referring to FIG. 21, an organic material is deposited on a second light-transmitting film (LT2) to form a light-blocking layer, and then the light-blocking layer is etched to form a light-blocking film (LS). The sides of the light-blocking film (LS) may be surrounded by the second light-transmitting film (LT2). Additionally, the second light-transmitting film (LT2) may be disposed on the lower surface of the light-blocking film (LS). The upper surface of the second light-transmitting film (LT2) and the upper surface of the light-blocking film (LS) may be flat.

[0176] As shown in FIGS. 15 to 21, a second light-transmitting film (LT2) is formed on the first light-transmitting films (LT1). As a result, even if the first light-transmitting films (LT1) are over-etched during the etching process and the width of each of the first light-transmitting films (LT1) is reduced, the reduced width of each of the first light-transmitting films (LT1) can be compensated by the width of the second light-transmitting film (LT2), thereby preventing the light transmittance of the aperture (OA) from being lowered.

[0177] FIG. 22 is a flowchart showing a method for manufacturing a fingerprint sensor according to another embodiment. FIG. 23 and FIG. 24 are example drawings for explaining the method for manufacturing a fingerprint sensor of FIG. 22.

[0178] Hereinafter, a method for manufacturing a fingerprint sensor (400) according to another embodiment will be described in conjunction with FIGS. 22 to 24.

[0179] Steps S210 to S230 of FIG. 22 differ from steps S110 to S130 of FIG. 15 only in that they form third light-transmitting films (LT3) instead of mask patterns (MS).

[0180] The third light-transmitting films (LT3) are used as masks and are substantially identical to the mask patterns (MS). However, the third light-transmitting films (LT3) may be materials capable of transmitting light. For example, the third light-transmitting films (LT3) may be organic films such as photoresist. Alternatively, the mask patterns (MS) may be inorganic films such as transparent conductive oxides (TCOs) like Induin Tin Oxide (ITO) or Induin Zinc Oxide (IZO).

[0181] Referring to FIG. 22, a second light-transmitting film (LT2) is formed on the first light-transmitting films (LT1) and the third light-transmitting films (LT3). (S240 of FIG. 22)

[0182] The second light-transmitting film (LT2) can be formed on the sides of each of the first light-transmitting films (LT1) and on the top and sides of each of the third light-transmitting films (LT3). Additionally, it can be formed on the flattening film (PLA) of the light-sensing layer (410) between the first light-transmitting films (LT1). Since the second light-transmitting film (LT2) has good step coverage, it can be continuously connected without interruption.

[0183] Referring to FIG. 24, a light-blocking film (LS) is formed between the first light-transmitting films (LT1). (S250 of FIG. 22)

[0184] An organic material is deposited on the second light-transmitting film (LT2) to form a light-blocking layer, and then the light-blocking layer is etched to form a light-blocking film (LS). The sides of the light-blocking film (LS) may be surrounded by the second light-transmitting film (LT2). Additionally, the second light-transmitting film (LT2) may be disposed on the lower surface of the light-blocking film (LS). The upper surface of the second light-transmitting film (LT2) and the upper surface of the light-blocking film (LS) may be flat.

[0185] As shown in FIGS. 22 to 24, since the second light-transmitting film (LT2) is formed on the third light-transmitting films (LT3) without removing the third light-transmitting films (LT3), the process of removing the third light-transmitting films (LT3) can be eliminated. Therefore, the efficiency of the manufacturing process for manufacturing the fingerprint sensor (400) can be increased.

[0186] Although embodiments of the present invention have been described above with reference to the attached drawings, those skilled in the art will understand that the present invention may be implemented in other specific forms without changing the technical concept or essential features thereof. Therefore, the embodiments described above should be understood as illustrative in all respects and not restrictive. Explanation of the symbols

[0187] 10: Display device 100: Display panel 200: Display driver 300: Display circuit board 400: Fingerprint sensor 410: Light sensing layer 420: Collimator layer LT1: First light-transmitting film LT2: Second light-transmitting film LS: Light-blocking film LT3: Third light-transmitting film CF: Color filter MS: Mask pattern LT: Light-transmitting layer

Claims

Claim 1 A fingerprint sensor comprising: a light sensing layer including a light sensing element through which a sensing current flows according to incident light; and a collimator layer disposed on the light sensing layer, wherein the collimator layer comprises: first light-transmitting films disposed spaced apart from each other; a light-blocking film disposed between the first light-transmitting films; and a second light-transmitting film disposed between each of the first light-transmitting films and the light-blocking film, wherein the second light-transmitting film is a single continuous film, and the second light-transmitting film is disposed on the upper surface of the first light-transmitting films and the lower surface of the light-blocking film, and disposed between the side surface of the first light-transmitting films and the side surface of the light-blocking film, and not disposed on the lower surface of the first light-transmitting films and the upper surface of the light-blocking film. Claim 2 A fingerprint sensor according to claim 1, wherein the refractive index of each of the first light-transmitting films is the same as the refractive index of the second light-transmitting film. Claim 3 A fingerprint sensor according to claim 1, wherein the refractive index of each of the first light-transmitting films is greater than the refractive index of the second light-transmitting film. Claim 4 A fingerprint sensor according to claim 2 or 3, wherein the first light-transmitting films are organic films and the second light-transmitting film is an inorganic film. Claim 5 In claim 1, the second light-transmitting film is a fingerprint sensor disposed on the upper surface and sides of each of the first light-transmitting films. Claim 6 In claim 1, the second light-transmitting film is a fingerprint sensor disposed on the lower surface of the light-blocking film. Claim 7 A fingerprint sensor according to claim 1, wherein the length in one direction of any one of the first light-transmitting films is longer than the length in one direction of a light-blocking film disposed between adjacent first light-transmitting films in said direction. Claim 8 A fingerprint sensor according to claim 5, further comprising a third light-transmitting film disposed on the upper surface of each of the first light-transmitting films and covered by the second light-transmitting film. Claim 9 In claim 8, the fingerprint sensor in which the refractive index of each of the first light-transmitting films is the same as the refractive index of the third light-transmitting film. Claim 10 In claim 8, a fingerprint sensor in which the refractive index of each of the first light-transmitting films is greater than the refractive index of the third light-transmitting film. Claim 11 In claim 8, the third light-transmitting film is a fingerprint sensor composed of a photoresist or a transparent conductive oxide. Claim 12 In claim 1, the height of the light-blocking film is lower than the height of the first light-transmitting film. Claim 13 A fingerprint sensor according to claim 12, further comprising a transparent adhesive member disposed on the light-blocking film and having a refractive index greater than that of the first light-transmitting film. Claim 14 A fingerprint sensor according to claim 1, comprising a color filter disposed on the second light-transmitting film and the light-blocking film. Claim 15 In claim 14, the color filter is a fingerprint sensor that transmits light in a wavelength band corresponding to green light, or transmits light in a wavelength band corresponding to green light and light in a wavelength band corresponding to blue light. Claim 16 A display device comprising: a display panel for displaying an image; and a fingerprint sensor disposed on one side of the display panel and detecting light passing through the display panel, wherein the fingerprint sensor comprises: a light-sensing layer including a light-sensing element through which a detection current flows according to incident light; and a collimator layer disposed on the light-sensing layer, wherein the collimator layer comprises: first light-transmitting films disposed spaced apart from each other; a light-blocking film disposed between the first light-transmitting films; and a second light-transmitting film disposed between each of the first light-transmitting films and the light-blocking film, wherein the second light-transmitting film is a single continuous film, and the second light-transmitting film is disposed on the upper surface of the first light-transmitting films and the lower surface of the light-blocking film, and disposed between the side of the first light-transmitting films and the side of the light-blocking film, and not disposed on the lower surface of the first light-transmitting films and the upper surface of the light-blocking film. Claim 17 A method for manufacturing a fingerprint sensor comprising: forming a light-sensing layer including a light-sensing element through which a sensing current flows according to incident light; forming a light-transmitting layer by depositing an organic material on the light-sensing layer; forming mask patterns on the light-transmitting layer; etching the light-transmitting layer according to the mask patterns to form first light-transmitting films; removing the mask patterns; forming a second light-transmitting film by depositing an inorganic material on the first light-transmitting films; and forming a light-blocking film by depositing an organic material on the second light-transmitting film, wherein the second light-transmitting film is a single continuous film, and the second light-transmitting film is disposed on the upper surface of the first light-transmitting films and the lower surface of the light-blocking film, and disposed between the side surface of the first light-transmitting films and the side surface of the light-blocking film, and not disposed on the lower surface of the first light-transmitting films and the upper surface of the light-blocking film. Claim 18 In claim 17, the step of forming mask patterns on the light-transmitting layer is a method for manufacturing a fingerprint sensor in which the mask patterns are arranged in a first direction and a second direction intersecting the first direction. Claim 19 In claim 17, the step of etching the light-transmitting layer according to the mask patterns to form first light-transmitting films is a method for manufacturing a fingerprint sensor in which the first light-transmitting films are arranged in a first direction and a second direction intersecting the first direction. Claim 20 In claim 17, the step of forming a second light-transmitting film by depositing an inorganic material on the first light-transmitting films is a method for manufacturing a fingerprint sensor disposed on the upper surface and side surfaces of each of the first light-transmitting films and on the light-sensing layer between the first light-transmitting films.

Images