CN113642396B - Sensing device - Google Patents

Abstract

A sensing device comprises a sensing structure layer, a first inorganic layer, a first shading pattern, a first organic pattern layer, a second inorganic layer, a second shading pattern, a second organic pattern layer, a third inorganic layer and a plurality of microlenses. The first inorganic layer is located on the sensing structure layer. The first light shielding pattern is located on the first inorganic layer. The first organic pattern layer is positioned on the first shading pattern and provided with a first opening. The second inorganic layer covers the top surface and the sidewalls of the first organic pattern layer. The second light shielding pattern is positioned on the second inorganic layer. The second organic pattern layer is positioned on the second shading pattern and provided with a second opening. The third inorganic layer covers the top surface and the sidewalls of the second organic pattern layer. A plurality of microlenses are located on the third inorganic layer.

Description

Sensing device

Technical Field

The present invention relates to a sensing device, and more particularly, to a fingerprint sensing device.

Background

Portable electronic devices equipped with biometric systems (e.g., fingerprints or irises) are currently moving toward full-screen or ultra-narrow bezel, and thus, under-screen optical sensors have been applied to portable electronic devices in recent years. The above-mentioned under-screen optical sensor is to set the micro-optical imaging device under the screen of the portable electronic device, and obtain the image of the object pressed above the screen through the partial light-transmitting area of the screen. Taking an under-screen fingerprint sensor as an example, the under-screen fingerprint sensor generally comprises a sensing structure layer and an optical mechanical structure layer arranged above the sensing structure layer, wherein the optical mechanical structure layer is required to be designed with a certain thickness as a focal length due to the micro lenses, so that the optical mechanical structure layer comprises a plurality of thick film structures stacked with each other; however, the thick film structure itself has a large stress, so that the fingerprint sensor is warped after being formed, which may have an adverse effect on the subsequent processes such as cutting the fingerprint sensor or bonding the fingerprint sensor to the display panel.

Disclosure of Invention

The invention provides a sensing device which can solve the problem of warping caused by the arrangement of a multi-layer structure.

The sensing device comprises a sensing structure layer, a first inorganic layer, a first shading pattern, a first organic pattern layer, a second inorganic layer, a second shading pattern, a second organic pattern layer, a third inorganic layer and a plurality of microlenses. The sensing structure layer is positioned on the substrate and comprises a plurality of sensing units. The first inorganic layer is located on the sensing structure layer. The first shading pattern is positioned on the first inorganic layer and defines a first light passing area, wherein the first light passing area corresponds to the sensing elements of the plurality of sensing units. The first organic pattern layer is positioned on the first shading patterns and comprises a plurality of first organic patterns, wherein first openings are arranged between adjacent first organic patterns. The second inorganic layer covers the top surface and the sidewalls of the first organic pattern layer. The second light shielding pattern is positioned on the second inorganic layer and defines a second light passing area, wherein the second light passing area corresponds to the first light passing area. The second organic pattern layer is positioned on the second shading patterns and comprises a plurality of second organic patterns, wherein second openings are arranged between adjacent second organic patterns, and the second openings correspond to the first openings. The plurality of microlenses corresponds to the second light passing region.

In an embodiment of the invention, the first light shielding pattern of the portion is exposed by the first opening, and the second light shielding pattern covers a sidewall of the first organic pattern layer.

In an embodiment of the invention, a thickness of the first inorganic layer, a thickness of the second inorganic layer, and a thickness of the third inorganic layer are between 500 angstroms and 3000 angstroms.

In an embodiment of the invention, a width of the first opening is at least greater than 2 micrometers, and a width of the second opening is at least greater than 3 micrometers.

In an embodiment of the invention, the sensing device further includes a fourth inorganic layer, a third organic pattern layer, and a filter pattern layer. The fourth inorganic layer is disposed between the second inorganic layer and the third inorganic layer, and covers the top surface and the sidewalls of the second organic pattern layer. The third organic pattern layer is positioned on the fourth inorganic layer and comprises a plurality of third organic patterns, wherein third openings are arranged between adjacent third organic patterns, and the third openings correspond to the first openings and the second openings. The filter pattern layer is located between the fourth inorganic layer and the third organic pattern layer.

In an embodiment of the invention, the sensing device further includes a third light shielding pattern disposed on the third inorganic layer and defining a third light passing area, and the third light passing area corresponds to the second light passing area.

In an embodiment of the invention, the third light shielding pattern covers a sidewall of the first organic pattern layer, a sidewall of the second organic pattern layer, a sidewall of the filter pattern layer, and a sidewall of the third organic pattern layer.

In an embodiment of the invention, a thickness of the first inorganic layer, a thickness of the second inorganic layer, a thickness of the third inorganic layer, and a thickness of the fourth inorganic layer are between 500 angstroms and 3000 angstroms.

In an embodiment of the invention, a width of the first opening is at least greater than 2 micrometers, a width of the second opening is at least greater than 3 micrometers, and a width of the third opening is at least greater than 8 micrometers.

In an embodiment of the invention, each of the plurality of sensing units includes an active device and a sensing device, wherein the active device is electrically connected to the sensing device.

In an embodiment of the invention, the sensing device further includes a scan line and a data line, wherein the scan line and the data line are disposed on the substrate and are electrically connected to the active device respectively.

Based on the above, the sensing device of the invention can achieve the effect of stress dispersion by enabling the openings to be arranged between the adjacent organic patterns, so that the problem of warping caused by the arrangement of a plurality of organic pattern layers in the sensing device of the invention is avoided. In addition, the sensing device of the invention is also provided with the inorganic layer in the opening, and the stress generated by the organic pattern layer can be reduced by utilizing the characteristic that the stress direction generated by the inorganic layer is opposite to the stress direction generated by the organic pattern layer, so that the problem of warping generated by the sensing device of the invention due to the arrangement of a plurality of organic pattern layers is further avoided.

Drawings

FIG. 1 is a schematic top view of a sensing device according to an embodiment of the invention.

FIG. 2A is a schematic cross-sectional view of a sensing device according to an embodiment of the section line A-A' of FIG. 1.

FIG. 2B is a schematic cross-sectional view of a sensing device according to another embodiment of the section line A-A' of FIG. 1.

Fig. 3 is a schematic cross-sectional view of an electronic device according to an embodiment of the invention.

Reference numerals illustrate:

10: electronic device

100. 200: sensing device

1000: display panel

A-A': line of cutting

BM1, BM2, BM3: shading pattern

BP1, BP2, BP3, BP4: inorganic layer

CH: semiconductor layer

D: drain electrode

DL: reading line

F: finger with finger tip

FG: frame glue

FL: optical filtering pattern layer

G: grid electrode

GL: inter-gate insulating layer

IL1, IL2: organic layer

L1: illumination beam

L2: sensing light beam

LE: light-emitting structure

LR1, LR2, LR3: light passing region

ML: micro lens

O, OP1, OP2, OP3: an opening

PL1, PL2, PL3: organic pattern layer

pL1_ S, PL2_ S, PL3 _3_S: side wall

pL1_ T, PL2_ T, PL3 _3_T: top surface

S: source electrode

SB: substrate board

SC: sensing element

SC1: first electrode

SC2: photosensitive layer

SC3: second electrode

SE: sensing structure layer

SL: scanning line

SU: sensing unit

T: active device

Detailed Description

FIG. 1 is a schematic top view of a sensing device according to an embodiment of the invention. FIG. 2A is a schematic cross-sectional view of a sensing device according to an embodiment of the section line A-A' of FIG. 1.

Referring to fig. 1 and 2A, the sensing device 100 of the present embodiment includes a substrate SB, a sensing structure layer SE, an inorganic layer BP1, a light shielding pattern BM1, an organic pattern layer PL1, an inorganic layer BP2, a light shielding pattern BM2, an organic pattern layer PL2, an inorganic layer BP3, a filter pattern layer FL, an organic pattern layer PL3, an inorganic layer BP4, and a plurality of microlenses ML.

In some embodiments, the substrate SB may be a flexible substrate or a rigid substrate. In some embodiments, the sensing structure layer SE may include the following components, but it should be noted that the present invention is not limited thereto. The sensing structure layer SE may include, for example, a plurality of sensing units SU, scan lines SL, and read lines DL. In addition, the sensing structure layer SE may further include a power supply line (not shown), and the invention is not limited thereto.

In some embodiments, each of the plurality of sensing units SU includes an active device T and a sensing device SC, but the invention is not limited thereto. The active device T is disposed on the substrate SB, and includes a gate G, a semiconductor layer CH, a source S, and a drain D. The gate electrode G is provided in correspondence with the semiconductor layer CH, for example, with the inter-gate insulating layer GL provided therebetween. The source electrode S and the drain electrode D are disposed on the inter-gate insulating layer GL and partially contact the semiconductor layer CH. The scan line SL and the read line DL are also disposed on the substrate SB, wherein the scan line SL is electrically connected to the source S of the active device T, and the read line DL is electrically connected to the drain D of the active device T to read the signal sensed by the sensing device SC. In some embodiments, the extending direction of the scan line SL and the extending direction of the read line DL are staggered, but the invention is not limited thereto. The scan lines SL and the read lines DL belong to different layers, for example. In detail, in some embodiments, the scan line SL and the gate electrode G belong to the same layer (first metal layer), and the read line DL and the source electrode S and the drain electrode D belong to the same layer (second metal layer). The following is a description of a method for forming the first metal layer, but it should be noted that the invention is not limited thereto. First, a first metal material layer (not shown) may be formed on the substrate SB comprehensively by physical vapor deposition or metal chemical vapor deposition. Next, a patterned photoresist material layer (not shown) is formed on the first metal material layer. Then, an etching process is performed on the first metal material layer by using the patterned photoresist layer as a mask, so as to form the scanning lines SL and the grid electrode G. In the present embodiment, the active device T is any bottom gate thin film transistor known to those skilled in the art. However, the present embodiment is exemplified by a bottom gate thin film transistor, but the present invention is not limited thereto. In other embodiments, the active device T may be a top gate type thin film transistor or other suitable type thin film transistor.

The sensing element SC is also disposed on the substrate SB, and includes a first electrode SC1, a photosensitive layer SC2, and a second electrode SC3. The first electrode SC1, the photosensitive layer SC2, and the second electrode SC3 are stacked in this order on the substrate SB, for example. In some embodiments, the area of the second electrode SC3 is larger than the area of the photosensitive layer SC2, and the contours of the first electrode SC1 and the second electrode SC3 may partially overlap. In the embodiment, the first electrode SC1 and the read line DL, the source S and the drain D are the same layer (the second metal layer), but the invention is not limited thereto. In other embodiments, the first electrode SC1 may be formed of another metal layer (third metal layer). In some embodiments, the first electrode SC1 and the second electrode SC2 may comprise a light transmissive conductive material or a light opaque conductive material, depending on the use of the sensing device 100. In this embodiment, the sensing device 100 can be used as an under-screen fingerprint sensor, so that light from the outside (such as light reflected by a fingerprint) passes through the second electrode SC3 and is incident on the photosensitive layer SC2, and based on this, the second electrode SC3 is made of a transparent conductive material. The photosensitive layer SC2 has a characteristic of converting light energy into electric energy to realize an optical sensing function. In some embodiments, the material of the photosensitive layer SC2 may include a silicon-rich material, which may be a silicon-rich oxide, a silicon-rich nitride, a silicon-rich oxynitride, a silicon-rich carbide, a silicon-rich oxycarbide, a hydrogenated silicon-rich oxide, a hydrogenated silicon-rich nitride, a hydrogenated silicon-rich carbide, or other suitable material or combination thereof.

In some embodiments, the sensing structure layer SE may further include an organic layer IL1 and an organic layer IL2. The organic layer IL1 is located on the first electrode SC1 of the active device T and the sensing device SC and covers the active device T. In some embodiments, the organic layer IL1 has an opening O exposing the first electrode SC1 of the sensing element SC, wherein the photosensitive layer SC2 is disposed in the opening O and contacts the first electrode SC1, and the second electrode SC3 is disposed on the organic layer IL1 and contacts the photosensitive layer SC 2. The organic layer IL1 is formed by, for example, spin coating. The material of the organic layer IL1 is, for example, an organic insulating material, which may be polyimide, polyester, benzocyclobutene (BCB), polymethyl methacrylate (PMMA), polyvinyl phenol (4-vinylphenol), PVP, polyvinyl alcohol (polyvinyl alcohol, PVA), polytetrafluoroethylene (PTFE), hexamethyldisiloxane (HMDSO), or a stacked layer of at least two of the above materials, but the present invention is not limited thereto. In the embodiment, the organic layer IL1 has a single-layer structure, but the invention is not limited thereto. In other embodiments, the organic layer IL1 may be a multi-layer structure.

The organic layer IL2 is, for example, on the organic layer IL1 and covers the second electrode SC3 of the sensing element SC. The organic layer IL2 is formed by, for example, spin coating. The material of the organic layer IL2 is, for example, an organic insulating material, which may be polyimide, polyester, benzocyclobutene, polymethyl methacrylate, polyvinyl phenol, polyvinyl alcohol, polytetrafluoroethylene, hexamethyldisiloxane or a stacked layer of at least two of the above materials, but the invention is not limited thereto. In the embodiment, the organic layer IL2 has a single-layer structure, but the invention is not limited thereto. In other embodiments, the organic layer IL2 may be a multi-layer structure.

The inorganic layer BP1 is for example located on the sensing structure layer SE, i.e. on the organic layer IL2. The inorganic layer BP1 is formed by, for example, physical vapor deposition or chemical vapor deposition. In the present embodiment, the material of the inorganic layer BP1 may be silicon oxide, silicon nitride, silicon oxynitride, or a stacked layer of at least two of the above materials, but the present invention is not limited thereto. In the present embodiment, the inorganic layer BP1 has a single-layer structure, but the present invention is not limited thereto. In other embodiments, the inorganic layer BP1 may be a multilayer structure. In some embodiments, the thickness of the inorganic layer BP1 is between 500 angstroms and 3000 angstroms. In a preferred embodiment, the thickness of the inorganic layer BP1 is between 1500 angstroms and 2000 angstroms. In the present embodiment, the inorganic layer BP1 having the above thickness range can balance the warpage generated by the arrangement of the organic pattern layer PL1 later.

The light shielding pattern BM1 is located on the inorganic layer BP1, for example, and is used to define a light-emitting region LR1. In detail, the material of the light shielding pattern BM1 includes a light shielding and/or reflecting material, which may be a metal, an alloy, a nitride of the material, an oxide of the material, an oxynitride of the material, or other suitable light shielding and/or reflecting material. In some embodiments, the material of the light shielding pattern BM1 may be molybdenum, molybdenum oxide, or a stacked layer thereof. Based on this, the light-emitting passing region LR1 can be defined by a region where the light shielding pattern BM1 is not provided. The light shielding pattern BM1 can effectively prevent stray light from entering the plurality of sensing units SU, so as to prevent the stray light from affecting the sensing result. In the present embodiment, the light passing region LR1 is provided corresponding to the sensing element SC of the sensing unit SU so that the sensing element SC can convert light passing through the outside of the light passing region LR1 into a corresponding electrical signal. In addition, in some embodiments, the region where the light shielding pattern BM1 is disposed may be used to shield the active element T (not shown in the drawings) of the sensing unit SU. In detail, the light shielding pattern BM1 is located above the active device T and at least shields the semiconductor layer CH of the active device T, so as to prevent the light from the outside from irradiating the semiconductor layer CH and thus prevent the active device T from generating electric leakage. The light shielding pattern BM1 is formed by, for example, first forming a light shielding pattern material layer (not shown) by sputtering or other methods. Next, a patterned photoresist material layer (not shown) is formed on the light shielding pattern material layer. Then, an etching process is performed on the light shielding pattern material layer by using the patterned photoresist layer as a mask, so as to form a light shielding pattern BM1.

The organic pattern layer PL1 is located on the inorganic layer BP1, for example, and covers the light shielding pattern BM1. The organic pattern layer PL1 is formed by, for example, first forming an organic pattern material layer (not shown) by a spin coating method. Next, a patterned photoresist material layer (not shown) is formed on the organic pattern material layer. And then, using the patterned photoresist layer as a mask, and carrying out an etching process on the organic pattern material layer. The material of the organic pattern layer PL1 is, for example, an organic insulating material, which may be polyimide, polyester, benzocyclobutene, polymethyl methacrylate, polyvinyl phenol, polyvinyl alcohol, polytetrafluoroethylene, hexamethyldisiloxane, or a stacked layer of at least two of the above materials, but the invention is not limited thereto. In the present embodiment, the organic pattern layer PL1 has a single-layer structure, but the present invention is not limited thereto. In other embodiments, the organic pattern layer PL1 may be a multi-layered structure. In the present embodiment, the organic pattern layer PL1 includes a plurality of organic patterns with an opening OP1 between adjacent organic patterns. The opening OP1 corresponds to, for example, a portion of the scan line SL, a portion of the read line DL, or a combination thereof, which is not limited to the present invention. For example, the opening OP1 may correspond to a region where the scan lines SL and the read lines DL are disposed, wherein each scan line SL and each read line DL may correspond to a region where one scan line SL and one read line DL in a group of more than two scan lines SL are disposed. In some embodiments, the opening OP1 has a width at least greater than 2 microns. The present embodiment can reduce the stress of the original unpatterned organic pattern material layer by providing the organic pattern layer PL1 with the opening OP1, thereby achieving the effect of stress dispersion.

The inorganic layer BP2 is located on the organic pattern layer PL1, for example, and covers the top surface pl1_t and the sidewall pl1_s of the organic pattern layer PL 1. In detail, a portion of the inorganic layer BP2 is disposed on the top surface pl1_t of the organic pattern layer PL1, and another portion of the inorganic layer BP2 is conformally disposed in the opening OP1 to cover the sidewall pl1_s of the organic pattern layer PL1 and a portion of the inorganic layer BP1. The inorganic layer BP2 is formed by, for example, physical vapor deposition or chemical vapor deposition. In some embodiments, the material of the inorganic layer BP2 may be silicon oxide, silicon nitride, silicon oxynitride, or a stacked layer of at least two of the foregoing materials. In this embodiment, the material of the inorganic layer BP2 is silicon nitride. In the present embodiment, the inorganic layer BP2 has a single-layer structure, but the present invention is not limited thereto. In other embodiments, the inorganic layer BP2 may be a multilayer structure. In some embodiments, the thickness of the inorganic layer BP2 is between 500 angstroms and 3000 angstroms. In a preferred embodiment, the thickness of the inorganic layer BP2 is between 1500 angstroms and 2000 angstroms. Because of the relationship between the included materials and the thickness, the stress direction generated by the inorganic layer BP2 is opposite to the stress direction generated by the organic pattern layer PL1, and thus the inorganic layer BP2 corresponding to the organic pattern layer PL1 may reduce the stress generated by the organic pattern layer PL1, and the inorganic layer BP2 disposed in the opening OP1 between adjacent organic patterns may balance the warpage generated by the disposition of the organic pattern layer PL 1.

The light shielding pattern BM2 is located on the inorganic layer BP2, for example, and is used to define the light-emitting region LR2. In detail, the material of the light shielding pattern BM2 includes a light shielding and/or reflecting material, which may be a metal, an alloy, a nitride of the material, an oxide of the material, an oxynitride of the material, or other suitable light shielding and/or reflecting material. In some embodiments, the material of the light shielding pattern BM2 may be molybdenum, molybdenum oxide, or a stacked layer thereof. Based on this, the light-emitting passing region LR2 can be defined by a region where the light shielding pattern BM2 is not provided. The arrangement of the light shielding pattern BM2 can effectively prevent stray light from entering the plurality of sensing units SU, so as to prevent the stray light from affecting the sensing result. In the present embodiment, the light passing region LR2 is provided corresponding to the light passing region LR1, that is, corresponding to the sensing element SC of the sensing unit SU, so that the sensing element SC can convert light passing through the light passing region LR2 and the outside of the light passing region LR1 into a corresponding electrical signal. The light shielding pattern BM2 is formed by, for example, first forming a light shielding pattern material layer (not shown) by sputtering or other methods. Next, a patterned photoresist material layer (not shown) is formed on the light shielding pattern material layer. Then, an etching process is performed on the light shielding pattern material layer by using the patterned photoresist layer as a mask, so as to form a light shielding pattern BM2.

The organic pattern layer PL2 is located on the inorganic layer BP2, for example, and covers the light shielding pattern BM2. The organic pattern layer PL2 is formed by, for example, first forming an organic pattern material layer (not shown) by a spin coating method. Next, a patterned photoresist material layer (not shown) is formed on the organic pattern material layer. And then, using the patterned photoresist layer as a mask, and carrying out an etching process on the organic pattern material layer. The material of the organic pattern layer PL2 is, for example, an organic insulating material, which may be polyimide, polyester, benzocyclobutene, polymethyl methacrylate, polyvinyl phenol, polyvinyl alcohol, polytetrafluoroethylene, hexamethyldisiloxane, or a stacked layer of at least two of the above materials, but the invention is not limited thereto. In the present embodiment, the organic pattern layer PL2 has a single-layer structure, but the present invention is not limited thereto. In other embodiments, the organic pattern layer PL2 may be a multi-layered structure. In the present embodiment, the organic pattern layer PL2 includes a plurality of organic patterns with an opening OP2 between adjacent organic patterns. The opening OP2 also corresponds to a portion of the scan line SL, a portion of the read line DL, or a combination thereof, which is not described herein. In the present embodiment, the opening OP2 corresponds to the opening OP1, that is, the opening OP2 and the opening OP1 communicate with each other. In some embodiments, the opening OP2 has a width at least greater than 3 microns. The present embodiment can also reduce the stress of the original unpatterned organic pattern material layer by providing the organic pattern layer PL2 with the opening OP2, thereby achieving the effect of stress dispersion.

The inorganic layer BP3 is located on the organic pattern layer PL2, for example, and covers the top surface pl2_t and the sidewall pl2_s of the organic pattern layer PL 2. In detail, a portion of the inorganic layer BP3 is disposed on the top surface pl2_t of the organic pattern layer PL2, and another portion of the inorganic layer BP3 is conformally disposed in the opening OP2 to cover the sidewall pl2_s of the organic pattern layer PL 2. In addition, in the present embodiment, since the opening OP2 and the opening OP1 are in communication with each other, the inorganic layer BP3 is conformally disposed in the opening OP1 to cover the portion of the inorganic layer BP2 located in the opening OP1. The inorganic layer BP3 is formed by, for example, physical vapor deposition or chemical vapor deposition. In some embodiments, the material of the inorganic layer BP3 may be silicon oxide, silicon nitride, silicon oxynitride, or a stacked layer of at least two of the foregoing materials. In this embodiment, the material of the inorganic layer BP3 is silicon nitride. In the present embodiment, the inorganic layer BP3 has a single-layer structure, but the present invention is not limited thereto. In other embodiments, the inorganic layer BP3 may be a multilayer structure. In some embodiments, the inorganic layer BP3 has a thickness between 500 angstroms and 3000 angstroms. In a preferred embodiment, the thickness of the inorganic layer BP3 is between 1500 angstroms and 2000 angstroms. Because of the relationship between the included materials and the thickness, the stress direction generated by the inorganic layer BP3 is opposite to the stress direction generated by the organic pattern layer PL2, and thus, the inorganic layer BP3 corresponding to the organic pattern layer PL2 may reduce the stress generated by the organic pattern layer PL2, and the inorganic layer BP3 disposed in the opening OP2 between adjacent organic patterns may balance the warpage generated by the disposition of the organic pattern layer PL 2.

The filter pattern layer FL is located on the inorganic layer BP3, for example. In the present embodiment, the filter pattern layer FL is disposed corresponding to the organic pattern layer PL2, and is not disposed in the openings OP2 and OP1. In some embodiments, the filter pattern layer FL may provide a technical effect of filtering. In detail, in the present embodiment, the filter pattern layer FL may be an infrared cut (IR-cut) filter pattern layer. That is, when the sensing unit SU of the present embodiment converts the external visible light into the electrical signal, the infrared light that is not visible to the naked eye is generally converted into the electrical signal, so that when the electrical signal is converted into the image for display, the displayed image is easily distorted or dispersed due to the infrared light. Based on this, this embodiment can avoid this problem by the arrangement of the filter pattern layer FL. However, the present invention is not limited thereto, and when the sensing unit SU of the present embodiment converts the external infrared light into the electrical signal, the filter pattern layer FL of the present embodiment may be an infrared light passing (IR pass) filter pattern layer. In other embodiments, the filter pattern layer FL may be another kind of filter layer.

The organic pattern layer PL3 is, for example, located on the inorganic layer BP3 and provided in correspondence with the filter pattern layer FL, that is, the filter pattern layer FL is located between the inorganic layer BP3 and the organic pattern layer PL 3. The organic pattern layer PL3 is formed by, for example, first forming an organic pattern material layer (not shown) by a spin coating method. Next, a patterned photoresist material layer (not shown) is formed on the organic pattern material layer. And then, using the patterned photoresist layer as a mask, and carrying out an etching process on the organic pattern material layer. The material of the organic pattern layer PL3 is, for example, an organic insulating material, which may be polyimide, polyester, benzocyclobutene, polymethyl methacrylate, polyvinyl phenol, polyvinyl alcohol, polytetrafluoroethylene, hexamethyldisiloxane, or a stacked layer of at least two of the above materials, but the present invention is not limited thereto. In the present embodiment, the organic pattern layer PL3 has a single-layer structure, but the present invention is not limited thereto. In other embodiments, the organic pattern layer PL3 may be a multi-layered structure. In the present embodiment, the organic pattern layer PL3 includes a plurality of organic patterns with an opening OP3 between adjacent organic patterns. The opening OP3 also corresponds to a portion of the scan line SL, a portion of the read line DL, or a combination thereof, which is not described herein. In the present embodiment, the opening OP3 corresponds to the opening OP2, i.e., the opening OP3, the opening OP2, and the opening OP1 communicate with each other to form the opening OP. In some embodiments, the opening OP3 has a width at least greater than 8 microns. The present embodiment can also reduce the stress of the original unpatterned organic pattern material layer by providing the organic pattern layer PL3 with the opening OP3, thereby achieving the effect of stress dispersion.

The inorganic layer BP4 is located on the organic pattern layer PL3, for example, and covers the top surface pl3_t and the sidewall pl3_s of the organic pattern layer PL 3. In detail, a portion of the inorganic layer BP4 is disposed on the top surface pl3_t of the organic pattern layer PL3, and another portion of the inorganic layer BP4 is conformally disposed in the opening OP3 to cover the sidewall pl3_s of the organic pattern layer PL 3. In addition, in the present embodiment, since the opening OP3, the opening OP2 and the opening OP1 are communicated with each other, the inorganic layer BP4 is conformally disposed in the opening OP2 and the opening OP1 to cover the portion of the inorganic layer BP3 located in the opening OP2 and the portion of the inorganic layer BP2 located in the opening OP1. The inorganic layer BP4 is formed by, for example, physical vapor deposition or chemical vapor deposition. In some embodiments, the material of the inorganic layer BP4 may be silicon oxide, silicon nitride, silicon oxynitride, or a stacked layer of at least two of the foregoing materials. In this embodiment, the material of the inorganic layer BP4 is silicon nitride. In the present embodiment, the inorganic layer BP4 has a single-layer structure, but the present invention is not limited thereto. In other embodiments, the inorganic layer BP4 may be a multilayer structure. In some embodiments, the inorganic layer BP4 has a thickness between 500 angstroms and 3000 angstroms. In a preferred embodiment, the thickness of the inorganic layer BP4 is between 1500 angstroms and 2000 angstroms. Because of the relationship of the included materials and thicknesses, the stress direction generated by the inorganic layer BP4 is opposite to the stress direction generated by the organic pattern layer PL3, and thus the inorganic layer BP4 corresponding to the organic pattern layer PL3 may reduce the stress generated by the organic pattern layer PL3, and the inorganic layer BP4 disposed in the opening OP3 between adjacent organic patterns may balance warpage generated by the disposition of the organic pattern layer PL 3.

The sensing device 100 of the present embodiment may further include a light shielding pattern BM3. The light shielding pattern BM3 is located on the inorganic layer BP4, for example, and is used to define the light-emitting region LR3. In detail, the material of the light shielding pattern BM3 includes a light shielding and/or reflecting material, which may be a metal, an alloy, a nitride of the material, an oxide of the material, an oxynitride of the material, or other suitable light shielding and/or reflecting material. In some embodiments, the material of the light shielding pattern BM3 may be molybdenum, molybdenum oxide, or a stacked layer thereof. Based on this, the light-emitting passing region LR3 can be defined by a region where the light shielding pattern BM3 is not provided. The arrangement of the light shielding pattern BM3 can effectively prevent stray light from entering the plurality of sensing units SU, so as to prevent the stray light from affecting the sensing result. In the present embodiment, the light passing region LR3 is provided in correspondence with the light passing region LR2, that is, in correspondence with the sensing element SC of the sensing unit SU, so that the sensing element SC can convert light passing through the light passing region LR3, the light passing region LR2, and the outside of the light passing region LR1 into corresponding electrical signals. The light shielding pattern BM3 is formed by, for example, first forming a light shielding pattern material layer (not shown) by sputtering or other methods. Next, a patterned photoresist material layer (not shown) is formed on the light shielding pattern material layer. Then, an etching process is performed on the light shielding pattern material layer by using the patterned photoresist layer as a mask, so as to form a light shielding pattern BM3.

The plurality of microlenses ML are located, for example, on the inorganic layer BP4 and correspond to the second light passing region LR2, i.e., are disposed in the third light passing region LR3. In detail, the plurality of microlenses ML are located in the third light passing region LR3 defined by the light shielding pattern BM3 and are provided corresponding to the plurality of sensing units SU. For example, a plurality of microlenses ML are arranged in an array, and have a central axis (not shown) passing through the center thereof. In some embodiments, the openings OP1, OP2 and OP3 also have central axes (not shown) passing through the centers thereof, wherein the central axes of the microlenses ML are aligned with the central axes of the openings OP1, OP2 and OP3, but the invention is not limited thereto. Based on this, the microlenses ML can be used to further enhance the light collimation effect, so as to reduce the light leakage and light mixing caused by scattered light or refracted light. In some embodiments, the microlenses ML may be symmetrical biconvex lenses, asymmetrical biconvex lenses, plano-convex lenses, or meniscus lenses, which is not limited to the present invention. In addition, each or more of the microlenses ML are disposed corresponding to one sensing unit SU, but the invention is not limited thereto.

Based on the above, in this embodiment, by disposing multiple organic pattern layers on the sensing structure layer, an opening is formed between adjacent organic patterns in each layer, so that the stress of the original unpatterned multiple organic pattern material layers can be reduced, so as to achieve the effect of stress dispersion, and thus the problem of warpage of the sensing device due to the disposition of the multiple layers of structures is avoided. In addition, the inorganic layer is disposed in the opening, and the direction of stress generated by the inorganic layer is opposite to the direction of stress generated by the organic pattern layer by selecting a proper material and thickness, so that the stress generated by the organic pattern layer can be reduced by disposing the inorganic layer in the opening, which further avoids the problem of warpage generated by disposing multiple layers of organic pattern layers in the sensing device of the present embodiment.

FIG. 2B is a schematic cross-sectional view of a sensing device according to another embodiment of the section line A-A' of FIG. 1. It should be noted that the embodiment shown in fig. 2B uses the element numbers and part of the content of the embodiment in fig. 2A, where the same or similar elements are denoted by the same or similar numbers, and the description of the same technical content is omitted. The description and effects of the foregoing embodiments may be referred to for the description of the omitted parts, and the following embodiments will not be repeated, while the description of at least a part of the embodiment shown in fig. 2B, which is not omitted, may be referred to as the following description.

Referring to fig. 1 and fig. 2B, the main differences between the sensing device 200 of the present embodiment and the sensing device 100 of the foregoing embodiment are as follows: the light shielding patterns BM1, BM2 and BM3 of the sensing device 200 of this embodiment are further disposed in the opening OP. Specifically, the light shielding pattern BM1 of the portion provided on the inorganic layer BP1 is exposed without being covered with the organic pattern layer PL1, and the light shielding pattern BM1 of the portion is provided at the bottom of the opening OP1 from another point of view. Similarly, a portion of the light shielding pattern BM2 disposed on the inorganic layer BP2 is exposed without being covered by the organic pattern layer PL2, and from another point of view, the portion of the light shielding pattern BM2 is disposed on the sidewall pl1_s of the organic pattern layer PL1 and in the opening OP1, and covers the inorganic layer BP2 disposed in the opening OP1. In addition, a part of the light shielding patterns BM3 are further disposed in the openings OP1, OP2 and OP3, and from another perspective, the light shielding patterns BM3 disposed on one organic pattern layer PL3 and adjacent to the openings OP extend into the openings OP and are connected to the light shielding patterns BM3 disposed on the adjacent organic pattern layer PL3 and adjacent to the openings OP.

The sensing device 200 of the present embodiment can shield light (e.g. oblique light) from the outside and avoid light leakage by disposing the light shielding patterns BM1, BM2 and BM3 in the opening OP. Based on this, the sensing device 200 of the present embodiment can avoid stray light interference caused by oblique light to the sensing unit SU when used as an under-screen fingerprint sensor, thereby improving the signal-to-noise ratio of the light to obtain a clearer fingerprint image. In addition, the sensing device 200 of the present embodiment also avoids the distortion of the sensed image. Based on the above, the sensing device 200 of the present embodiment facilitates fingerprint recognition by disposing the light shielding patterns BM1, BM2 and BM3 in the opening OP.

Fig. 3 is a schematic cross-sectional view of an electronic device according to an embodiment of the invention.

Referring to fig. 3, fig. 3 illustrates an electronic device 10. In some embodiments, the electronic device 10 may be an off-screen fingerprint recognition device, such as a smart phone, a tablet computer, a notebook computer, or a touch-sensitive display device. The electronic device 10 of the present embodiment includes, for example, a display panel 1000 and a sensing device 100, wherein the display panel 1000 and the sensing device 100 can be bonded by a frame glue FG, which is not limited to the present invention. The display panel 1000 is adapted to provide the illumination light beam L1 to the finger F through a light emitting structure LE provided therein, and then reflect the sensing light beam L2 therethrough, for example. In the embodiment, the display panel 1000 is an organic light-emitting diode (OLED) display panel, but the invention is not limited thereto. In other embodiments, the display panel 1000 may be a liquid crystal display panel or other suitable display panel. The sensing device 100 is disposed below the display panel 1000, for example, to receive the sensing light beam L2 reflected by the finger F, thereby performing fingerprint recognition.

In summary, the sensing device of the present invention has the openings between the adjacent organic pattern layers in each layer by disposing the plurality of organic pattern layers on the sensing structure layer, so as to reduce the stress of the original unpatterned organic pattern material layer, thereby achieving the effect of stress dispersion, and avoiding the problem of warpage of the sensing device due to the disposition of the plurality of layers. In addition, the inorganic layer is also arranged in the opening, and the direction of stress generated by the inorganic layer is opposite to the direction of stress generated by the organic pattern layer by selecting proper materials and thickness, so that the stress generated by the organic pattern layer can be reduced by arranging the inorganic layer in the opening, and the problem of warping caused by arranging a plurality of layers of organic pattern layers in the sensing device is further avoided.

Claims (11)

1. A sensing device, comprising:

the sensing structure layer is positioned on the substrate and comprises a plurality of sensing units;

a first inorganic layer on the sensing structure layer;

a first light shielding pattern on the first inorganic layer and defining a first light passing region corresponding to the sensing elements of the plurality of sensing units;

the first organic pattern layer is positioned on the first shading patterns and comprises a plurality of first organic patterns, wherein first openings are formed between adjacent first organic patterns;

a second inorganic layer covering a top surface and sidewalls of the first organic pattern layer;

a second light shielding pattern on the second inorganic layer and defining a second light passing region corresponding to the first light passing region;

a second organic pattern layer on the second light shielding pattern and including a plurality of second organic patterns, wherein second openings are formed between adjacent second organic patterns, and the second openings correspond to the first openings;

a third inorganic layer covering a top surface and sidewalls of the second organic pattern layer; and

and a plurality of microlenses corresponding to the second light passing regions.

2. The sensing device of claim 1, wherein a portion of the first light shielding pattern is exposed by the first opening, and the second light shielding pattern covers a sidewall of the first organic pattern layer.

3. The sensing device of claim 1, wherein the thickness of the first inorganic layer, the thickness of the second inorganic layer, and the thickness of the third inorganic layer are between 500 angstroms and 3000 angstroms.

4. The sensing device of claim 1, wherein the width of the first opening is at least greater than 2 microns and the width of the second opening is at least greater than 3 microns.

5. The sensing device of claim 1, further comprising:

a fourth inorganic layer disposed between the second inorganic layer and the third inorganic layer and covering a top surface and sidewalls of the second organic pattern layer;

a third organic pattern layer on the fourth inorganic layer and including a plurality of third organic patterns, wherein third openings are provided between adjacent third organic patterns, and the third openings correspond to the first openings and the second openings; and

and a filter pattern layer between the fourth inorganic layer and the third organic pattern layer.

6. The sensing device of claim 5, further comprising a third light shielding pattern, wherein the third light shielding pattern is located on the third inorganic layer and defines a third light passing region, the third light passing region corresponding to the second light passing region.

7. The sensing device of claim 6, wherein the third light shielding pattern covers sidewalls of the first organic pattern layer, sidewalls of the second organic pattern layer, sidewalls of the filter pattern layer, and sidewalls of the third organic pattern layer.

8. The sensing device of claim 5, wherein a thickness of the first inorganic layer, a thickness of the second inorganic layer, a thickness of the third inorganic layer, and a thickness of the fourth inorganic layer is between 500 angstroms and 3000 angstroms.

9. The sensing device of claim 5, wherein the width of the first opening is at least greater than 2 microns, the width of the second opening is at least greater than 3 microns, and the width of the third opening is at least greater than 8 microns.

10. The sensing device of claim 1, wherein each of the plurality of sensing units comprises an active element and the sensing element, the active element being electrically connected to the sensing element.

11. The sensing device of claim 10, further comprising scan lines and data lines disposed on the substrate and each electrically connected to the active element.

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