Biometric recognition device

Abstract

A biometric identification device includes a substrate, a plurality of light sensing elements, a first dielectric layer, a plurality of first light shielding portions, a second dielectric layer, and a second light shielding portion. The light sensing elements are disposed on the substrate. The first dielectric layer is disposed on the light sensing elements. The first light shielding portions are disposed on the first dielectric layer, wherein each of the first light shielding portions has a first light transmission region and a first light shielding region surrounding the first light transmission region, the first light transmission region corresponds to and overlaps each of the light sensing elements, and at least two of the first light shielding portions are separated by a spacing region. The second dielectric layer is disposed on the first light shielding portions. The second light shielding portion is disposed on the second dielectric layer. At least part of the spacing region is within a range of a normal projection of the substrate and within a range of a normal projection of the second light shielding region on the substrate.

Description

Technical Field

[0001] This disclosure relates to a biometric identification device. Background Technology

[0002] With the development of technology, information security has become a major consideration for consumers when using electronic devices. Therefore, most electronic devices are now equipped with identity authentication mechanisms, among which biometric identification has become a trend in recent years.

[0003] However, current biometric identification devices suffer from poor image quality due to insufficient response of biometric signals caused by excessively high stray capacitance.

[0004] Therefore, the problem to be solved is how to provide a biometric identification device that reduces stray capacitance. Summary of the Invention

[0005] Some embodiments of this disclosure provide a biometric identification device, including a substrate, a plurality of photosensitive elements, a first dielectric layer, a plurality of first light-shielding portions, a second dielectric layer, and a second light-shielding portion. The photosensitive elements are disposed on the substrate. The first dielectric layer is disposed on the photosensitive elements. The plurality of first light-shielding portions are disposed on the first dielectric layer, wherein each first light-shielding portion has a first light-transmitting area and a first light-shielding area surrounding the first light-transmitting area, the first light-transmitting area corresponding to and overlapping each photosensitive element, and at least two of the first light-shielding portions are separated by a spacer. The second dielectric layer is disposed on the first light-shielding portion. The second light-shielding portion is disposed on the second dielectric layer, wherein the second light-shielding portion has a plurality of second light-transmitting areas and a second light-shielding area located between two adjacent second light-transmitting areas, each second light-transmitting area corresponding to each first light-transmitting area, and at least a portion of the spacer portion's orthographic projection area on the substrate is within the orthographic projection area of ​​the second light-shielding portion on the substrate.

[0006] In some embodiments, the first light-shielding portions are separated by intervals.

[0007] In some embodiments, a portion of the first light-shielding part is connected via a first light-shielding area.

[0008] In some implementations, the first light-shielding area is made of metal.

[0009] In some embodiments, the length of the first light-transmitting region ranges from 2.5 micrometers to 5 micrometers.

[0010] In some implementations, the outline shape of the first shading area when viewed from above includes a circle, a square, a pentagon, a hexagon, or an octagon.

[0011] In some embodiments, the distance between the center points of adjacent second light-transmitting areas is defined as P, the length of each second light-transmitting area is L2, the length of the interval area is S0, the length of the first light-transmitting area is L1, the vertical length from the outline edge of the first light-blocking area to the outline edge of the first light-transmitting area is L', and the length of the range of light projected onto each photosensitive element through each microlens is L0. Then, P-L2>S0; P-L1-2L'=S0; and L1+2L'>L0.

[0012] In some embodiments, the distance between the center points of adjacent second light-transmitting areas is defined as P, the length of each second light-transmitting area is L2, the length of the interval area is S0, the length of the first light-transmitting area is L1, the vertical length from the outline edge of the first light-blocking area to the outline edge of the first light-transmitting area is L', the length of the range of light projected onto each photosensitive element through each microlens is L0, the distance from the upper surface of the photosensitive element to the upper surface of the first dielectric layer is H0, and the distance from the upper surface of the first dielectric layer to the upper surface of the second dielectric layer is H1.

[0013]

[0014] In some embodiments, the length S0 of the interval region is in the range of 10 micrometers ≥ S ≥ 2.5; and the vertical length L' from the outline edge of the first light-shielding region to the outline edge of the first light-transmitting region is in the range of 10 micrometers ≥ L' ≥ 2.5 micrometers.

[0015] In some embodiments, the length L2 of each second light-transmitting region ranges from 10 micrometers ≥ L2 ≥ 2.5 micrometers; the length L1 of the first light-transmitting region ranges from 8 micrometers ≥ L1 ≥ 2.5 micrometers; the length L0 of the light range ranges from 10 micrometers ≥ L0 ≥ 2.5 micrometers; the distance H0 from the upper surface of the photosensitive element to the upper surface of the first dielectric layer ranges from 6 micrometers ≥ H0 ≥ 2 micrometers; and the distance H1 from the upper surface of the first dielectric layer to the upper surface of the second dielectric layer ranges from 30 micrometers ≥ H1 ≥ 5 micrometers.

[0016] In some embodiments, the first light-shielding area includes a first light-shielding metal layer and a first metal oxide layer disposed on the first light-shielding metal layer.

[0017] In some embodiments, the second light-shielding area includes a second light-shielding metal layer and a second metal oxide layer disposed on the second light-shielding metal layer.

[0018] In some implementations, the biometric identification device also includes an active element connected to a photosensitive element.

[0019] In some embodiments, the biometric identification device further includes a microlens disposed on the second light-shielding portion, wherein the orthographic projection range of the second light-transmitting area onto the substrate is located within the orthographic projection range of the microlens onto the substrate.

[0020] In some embodiments, the biometric identification device further includes multiple microlenses disposed on the second light-shielding part, wherein each microlens corresponds to a second light-transmitting area. Attached Figure Description

[0021] This disclosure can be more fully understood by reading the following detailed description of the embodiments with reference to the accompanying drawings.

[0022] Figure 1 A cross-sectional schematic diagram of a biometric identification device illustrating some embodiments of the present disclosure is shown.

[0023] Figure 2A A top view of a first block in a biometric identification device illustrating some embodiments of the present disclosure.

[0024] Figure 2B A top view of a second block in a biometric identification device illustrating some embodiments of the present disclosure.

[0025] Figure 2C A top view showing another example of a second block in a biometric identification device illustrating some embodiments of this disclosure.

[0026] Figure 2D The outline shape of the first light-shielding part in a biometric identification device according to some embodiments of the present disclosure is shown in top view.

[0027] Figure 3A A top view showing a first electrode layer, a photosensitive element, and an insulating layer portion filling a first light-transmitting area of ​​a biometric identification device according to some embodiments of the present disclosure.

[0028] Figures 3B to 3E The image shows a layered top view of a biometric identification device according to some embodiments of the present disclosure, including a first electrode layer, a photosensitive element, a second electrode layer, and an insulating layer portion filling a first light-transmitting area.

[0029] Figure 4A A top view illustrating a first electrode layer, a photosensitive element, and other examples of an insulating layer portion filling a first light-transmitting area of ​​a biometric identification device according to some embodiments of the present disclosure.

[0030] Figures 4B to 4E Layered top views showing, respectively, a first electrode layer, a photosensitive element, a second electrode layer, and other examples of an insulating layer portion filling a first light-transmitting area of ​​a biometric identification device according to some embodiments of the present disclosure.

[0031] Figure 5A A cross-sectional schematic diagram illustrating the movement of light through a biometric identification device in some embodiments of this disclosure.

[0032] Figure 5B Show Figure 5A Top view of the first light-shielding section in the middle part.

[0033] Figure 6A A cross-sectional schematic diagram of a biometric identification device is shown in some other embodiments of this disclosure.

[0034] Figure 6B A cross-sectional schematic diagram of a biometric identification device is shown in some other embodiments of this disclosure.

[0035] Explanation of reference numerals in the attached figures:

[0036] 100, 200, 300: Biometric identification devices

[0037] 110, 210, 310: substrate

[0038] 120, 220, 320: Buffer layer

[0039] 130, 132, 134, 136, 230, 232, 234, 236, 330, 332, 334, 336: Insulation layer

[0040] 136A: Insulation layer portion

[0041] 140, 142, 144, 240, 242, 244, 340, 342, 344: Dielectric layer

[0042] 150, 250, 350: First shaded section

[0043] 160°, 260°, 360°: Second shading section

[0044] 170, 270, 370: Cover plate

[0045] 280: Adhesive layer

[0046] A: Groove

[0047] T: Active component

[0048] SC: Semiconductor layer

[0049] GE: Gate electrode

[0050] S / D: Source / Drain Region

[0051] CA: Channel Area

[0052] GI: Gate Dielectric Layer

[0053] ILD: Interlayer Dielectric Layer

[0054] SR: Photosensitive element

[0055] E1: First electrode layer

[0056] E2: Second electrode layer

[0057] LT1: First light-transmitting zone

[0058] BR1: First shaded zone

[0059] BM1: First light-shielding metal layer

[0060] OX1: First metal oxide layer

[0061] LT2: Second light-transmitting zone

[0062] BR2: Second shaded area

[0063] BM2: Second light-shielding metal layer

[0064] OX2: Second metal oxide layer

[0065] SP: Interval

[0066] RL: Reflected light

[0067] SL: Stray Light

[0068] LN: Microlens

[0069] LNa: convex part

[0070] B1: First Box

[0071] B2: Second Box

[0072] B3, B4: Triangular box

[0073] L0, L1, L2: Length

[0074] L': Vertical length

[0075] H0, H1, H2: Distance

[0076] S0: Length

[0077] P: Distance

[0078] AA: Line AA

[0079] BB: Line BB

[0080] CC: Line CC

[0081] X: X-axis

[0082] Y: Y-axis

[0083] Z: Z-axis

[0084] d: diameter Detailed Implementation

[0085] The concept of this disclosure will be clearly explained below with reference to the accompanying drawings and detailed description. Any person skilled in the art who understands the preferred embodiments and examples of this disclosure may make changes and modifications based on the technology inspired by this disclosure without departing from the concept and scope of this disclosure.

[0086] The terminology used herein is for the purpose of describing particular embodiments only and is not restrictive. As used herein, unless the content clearly indicates otherwise, the singular forms “a,” “an,” and “the” are intended to include the plural forms, including “at least one.” “Or” means “and / or.” As used herein, the term “and / or” includes any and all combinations of one or more of the associated listed items. It should also be understood that, when used in this specification, the terms “comprising” and / or “comprising” specify the presence of the stated features, areas, integrals, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, areas, integrals, steps, operations, elements, components, and / or combinations thereof.

[0087] Exemplary embodiments are described herein with reference to top-view schematic diagrams as idealized embodiments. Therefore, variations in shape as a result of, for example, manufacturing techniques and / or tolerances can be expected. Consequently, the embodiments described herein should not be construed as limited to the specific shapes of the regions shown herein, but rather include, for example, shape deviations caused by manufacturing processes. For example, regions shown or described as flat may generally have rough and / or non-linear characteristics. Furthermore, acute angles shown may be rounded. Therefore, the regions shown in the figures are schematic in nature, and their shapes are not intended to show the precise shapes of the regions, nor are they intended to limit the scope of the claims.

[0088] The following are several embodiments to illustrate the touch device of the present invention in more detail. However, they are only illustrative examples and are not intended to limit the present invention. The scope of protection of the present invention shall be defined by the claims.

[0089] Figure 1 A cross-sectional schematic diagram of a biometric identification device 100 illustrating some embodiments of the present disclosure is shown.

[0090] The biometric identification device 100 includes a substrate 110, a buffer layer 120, an active element T, a gate dielectric layer GI, an interlayer dielectric layer ILD, multiple photosensitive elements SR, a first electrode layer E1, a second electrode layer E2, an insulating layer 130, a dielectric layer 140, multiple first light-shielding portions 150, second light-shielding portions 160, a microlens LN, and a cover plate 170.

[0091] In some embodiments, the biometric identification device 100 can be applied to fingerprint recognition, where the identified biometric features are, for example, features in the ridges and valleys of a fingerprint, but it is not limited thereto. In other embodiments, the biometric identification device 100 can also be applied to palmprint recognition, where the identified biometric features can be features in the ridges and valleys of a palmprint. For ease of explanation, fingerprint recognition will be used as an example below.

[0092] In some embodiments, the substrate 110 may be a light-transmitting material. For example, the substrate 110 may be a glass substrate, a quartz substrate, a sapphire substrate, an organic polymer substrate, or other suitable rigid substrates or flexible substrates.

[0093] A buffer layer 120 is disposed on the substrate 110. An active element T is disposed on the buffer layer 120. An interlayer dielectric layer (ILD) is disposed on the active element T. A photosensitive element SR is disposed on the first electrode layer E1; therefore, the photosensitive element SR is electrically connected to the active element T through the first electrode layer E1. In some embodiments, the material of the photosensitive element SR is silicon-rich oxide (SRO) or other suitable materials. In some embodiments, the material of the first electrode layer E1 is a metallic material, such as an opaque metallic material.

[0094] The active element T includes a semiconductor layer SC and a gate electrode GE located on the semiconductor layer SC. The semiconductor layer SC includes a source / drain region S / D and a channel region CA connecting the source / drain region S / D. In some embodiments, the channel region CA is polysilicon, and the source / drain region S / D is doped polysilicon. In other embodiments, the source / drain region S / D can be an alloy, a nitride of a metal, an oxide of a metal, an oxide oxynitride of a metal, or other suitable materials.

[0095] In one embodiment, a semiconductor layer SC is patterned and formed on a buffer layer 120, and then a gate dielectric layer GI covers the semiconductor layer SC. A gate electrode GE is patterned and formed on the gate dielectric layer GI. The semiconductor layer SC is doped to form source / drain regions S / D, and the undoped region in the semiconductor layer SC (located below the gate electrode GE) is the channel region CA. An interlayer dielectric layer ILD is formed on the gate dielectric layer GI and covers the gate electrode GE. An opening (penetrating both the gate dielectric layer GI and the interlayer dielectric layer ILD) is then formed between the gate dielectric layer GI and the interlayer dielectric layer ILD, and a metal material and a patterned metal material are deposited in the opening to form a first electrode layer E1 in the opening and on the interlayer dielectric layer ILD. A photosensitive element SR is then disposed on the first electrode layer E1, thereby electrically connecting the source / drain regions S / D and the photosensitive element SR through the first electrode layer E1.

[0096] An insulating layer 132 is disposed on the first electrode layer E1 and the interlayer dielectric layer ILD. In some embodiments, the insulating layer 132 partially covers the photosensitive element SR (e.g., covers the outer edge region of the photosensitive element SR, such as...). Figure 1 As shown, the insulating layer 132 forms a groove A on the photosensitive element SR.

[0097] In some embodiments, the insulating layer 132 may be made of a transparent insulating material, such as silicone rubber, acrylic resin, unsaturated polyester, polyurethane, epoxy resin, other suitable materials, derivatives thereof, or combinations thereof.

[0098] The second electrode layer E2 is disposed on the insulating layer 132 and the photosensitive element SR. In some embodiments, the second electrode layer E2 extends into the groove A, covering a portion of the photosensitive element SR (e.g., covering the central region of the photosensitive element SR) and is electrically connected to the photosensitive element SR (e.g., see [reference]). Figure 1 ).

[0099] In some embodiments, the material of the second electrode layer E2 includes a transparent conductive material, such as indium tin oxide (ITO), indium zinc oxide, aluminum tin oxide, aluminum zinc oxide, indium gallium zinc oxide, other suitable oxides, or a stacked layer of at least two of the above.

[0100] An insulating layer 134 is disposed on the insulating layer 132 and the second electrode layer E2. The material of the insulating layer 134 may be the same as or similar to that of the insulating layer 132, which will not be described in detail here.

[0101] A dielectric layer 142 is disposed on an insulating layer 134. A plurality of first light-shielding portions 150 are disposed on the dielectric layer 142, wherein each first light-shielding portion 150 has a first light-transmitting area LT1 and a first light-shielding area BR1 surrounding the first light-transmitting area LT1, the individual first light-transmitting area LT1 corresponds to and overlaps with an individual photosensitive element SR (for example, the center point of the individual first light-transmitting area LT1 overlaps with the center point of the photosensitive element SR), and at least two of the first light-shielding portions 150 are separated by a spacer area SP.

[0102] In some embodiments, the dielectric layer 142 may be made of organic materials, inorganic materials, or combinations thereof, including, but not limited to, epoxy resin, silicon oxide (SiOx), silicon nitride (SiNx), a composite layer composed of silicon oxide and silicon nitride, or other suitable dielectric materials. In some embodiments, the dielectric layer 142 is a transparent insulating material.

[0103] In some embodiments, the material of the first light-shielding area BR1 may be an inorganic material, an organic material, a metal, other suitable materials, or a combination thereof.

[0104] It is worth emphasizing that if the first light-shielding region BR1 is prepared using inorganic or organic materials, there is a process limitation that the length L1 of the first light-transmitting region LT1 must be greater than 5 micrometers. However, when the material of the first light-shielding region BR1 is metal, better process precision can be achieved, for example, the length L1 of the first light-transmitting region LT1 can be less than 5 micrometers (for example, between 2.5 micrometers and 5 micrometers). In some embodiments, the first light-shielding region BR1 includes a first light-shielding metal layer BM1 and a first metal oxide layer OX1 disposed on the first light-shielding metal layer BM1.

[0105] In some embodiments, the first light-shielding portions 150 are separated by a spacer area SP. For example, please refer to... Figure 1 The first box B1 and Figure 2A , Figure 2A A top view of the first block B1 of a biometric identification device 100 illustrating some embodiments of the present disclosure, wherein, along Figure 2A The cross section cut by line AA is... Figure 1 The first light-shielding portion 150 and the interval SP are in the first block B1. Each of the first light-shielding portions 150 has an interval SP between it.

[0106] In addition, it is worth emphasizing that when the first light-shielding area BR1 is metal, the design of the spacer area SP can reduce the contact area between the first light-shielding area BR1 (especially the first light-shielding metal layer BM1) and the dielectric layer 142, thereby reducing the parasitic capacitance between the first light-shielding area BR1 and the dielectric layer 142, thus reducing the interference of stray capacitance and increasing the accuracy of fingerprint signal detection.

[0107] In some other embodiments, although a portion of the first light-shielding portion 150 is separated by the spacer region SP, another portion of the first light-shielding portion 150 is connected by the first light-shielding region BR1. For example, please refer to... Figure 1 The second box B2 and Figure 2B , Figure 2B A top view of the biometric identification device 100 showing some embodiments of the present disclosure, in the second block B2, wherein, along Figure 2B The cross section cut by line BB is... Figure 1 The first light-shielding portion 150 in the second box B2. Figure 2B In the process, the first light-shielding part 150 is connected to another first light-shielding part 150 adjacent in the X-axis direction and another first light-shielding part 150 adjacent in the Y-axis direction.

[0108] Tongshen Figure 2BFrom a top view, the diameter d of the first light-shielding area BR1 connected to the first light-shielding part 150 along the X-axis is smaller than the length of the first light-shielding part 150 (twice the vertical length L'(2L') from the outline edge of the first light-transmitting area BR1 to the outline edge of the first light-transmitting area LT1 + the length L1 of the first light-transmitting area LT1), so as to reduce the contact area between the first light-shielding area BR1 and the dielectric layer 142, reduce parasitic capacitance, thereby reducing the interference of stray capacitance and increasing the accuracy of fingerprint signal detection.

[0109] It is understood that the first light-shielding parts 150 can be connected to each other in any way, without any restrictions. For example, please refer to... Figure 1 The second box B2 and Figure 2C , Figure 2C A top view showing another example of the second block B2 in a biometric identification device 100 illustrating some embodiments of this disclosure, wherein, along Figure 2C The cross section intercepted by line CC is... Figure 1 The first light-shielding portion 150 in the second box B2. Figure 2C middle, Figure 2C The first light-shielding portion 150 in the lower left corner is connected to another first light-shielding portion 150 adjacent in the X-axis direction, but not to yet another first light-shielding portion 150 adjacent in the Y-axis direction. However, in Figure 2C The two first light-shielding parts 150 on the right side are not connected to any adjacent first light-shielding parts 150.

[0110] In some implementations, see, for example Figure 2D , Figure 2D The outline shape of the first light-shielding portion 150 in a biometric identification device 100 according to some embodiments of the present disclosure is shown in top view. Figure 2D The outline shape of the first light-shielding part 150 in top view includes a circle, square, pentagon, hexagon, or octagon. It can be understood that when the first light-shielding area BR1 (see...) Figure 1 When the material is metal, the outline of the first light-shielding part 150 is circular. Compared with other shapes, it can minimize the contact area between the first light-shielding area BR1 and the dielectric layer 142 while taking into account the light-shielding effect, reduce parasitic capacitance, thereby reducing the interference of stray capacitance and increasing the accuracy of fingerprint signal detection.

[0111] Please return Figure 1 An insulating layer 136 is disposed on the dielectric layer 142 and the first light-shielding metal layer BM1, and fills the first light-transmitting region LT1 and the spacer region SP. The material of the insulating layer 136 may be the same as or similar to that of the insulating layer 132, which will not be described in detail here.

[0112] Next, please see Figures 3A to 3E . Figure 3AThe image shows a top view of a biometric identification device 100 according to some embodiments of the present disclosure, including a first electrode layer E1, a photosensitive element SR, and an insulating layer portion 136A that fills a first light-transmitting area LT1. Figures 3B to 3E The following are layered top views of a biometric identification device 100 according to some embodiments of the present disclosure, showing a first electrode layer E1, a photosensitive element SR, a second electrode layer E2, and an insulating layer portion 136A filling a first light-transmitting area LT1. The outline shapes of the first electrode layer E1, the photosensitive element SR, and the second electrode layer E2 in top view are substantially hexagonal (e.g., regular hexagonal), and the outline shape of the insulating layer portion 136A in top view can be circular. The connection method of each layer element can be adjusted according to the actual application of the circuit.

[0113] For example, in Figure 3B In the first electrode layer E1, four hexagons are arranged in an array, forming a group, with the outer contours of the four hexagons extending and connecting. Figure 3D In the middle, the second electrode layer E2 consists of groups of four hexagons arranged in an array, with the four hexagons intersecting and connecting. Figure 3C In this model, the photosensitive element SR is a separate hexagon and is not connected to each other.

[0114] It is understood that the outline shapes of the first electrode layer E1, the photosensitive element SR, and the second electrode layer E2 when viewed from above are not limited to hexagons. For example, please see... Figures 4A to 4E . Figure 4A A top view of a biometric identification device 100 according to some embodiments of the present disclosure, showing a first electrode layer E1, a photosensitive element SR, and an insulating layer portion 136A filling a first light-transmitting area LT1, and other examples thereof. Figures 4B to 4E The following is a layered top view of a biometric identification device 100 according to some embodiments of the present disclosure, showing a first electrode layer E1, a photosensitive element SR, a second electrode layer E2, and an insulating layer portion 136A filling a first light-transmitting area LT1, respectively.

[0115] Figures 4A to 4E and Figures 3A to 3E They are basically the same, except that the outlines of the first electrode layer E1, the photosensitive element SR, and the second electrode layer E2 are basically octagonal when viewed from above.

[0116] Next, please return to Figure 1A dielectric layer 144 is disposed on an insulating layer 136. A second light-shielding portion 160 is disposed on the dielectric layer 144, wherein the second light-shielding portion 160 has a plurality of second light-transmitting areas LT2 and a second light-shielding area BR2 located between two adjacent second light-transmitting areas LT2. Each second light-transmitting area LT2 corresponds to a particular first light-transmitting area LT1 (for example, the center point of a particular second light-transmitting area LT2 overlaps with the center point of a particular first light-transmitting area LT1), and at least a portion of the orthographic projection range of the spacer area SP on the substrate 110 is within the orthographic projection range of the second light-shielding area BR2 on the substrate 110. In some embodiments, the orthographic projection range of all spacer areas SP on the substrate 110 falls within the orthographic projection range of the second light-shielding area BR2, and the second light-shielding area BR2 blocks all spacer areas SP, preventing the spacer areas SP from being exposed and allowing stray light to shine on the photosensitive element SR through the spacer areas SP, interfering with the detection of the fingerprint signal.

[0117] In some embodiments, the material of dielectric layer 144 may be the same as or similar to that of dielectric layer 142, which will not be described further here.

[0118] In some embodiments, the material of the second light-shielding region BR2 may be an inorganic material, an organic material, a metal, other suitable materials, or a combination thereof. In some embodiments, the second light-shielding region BR2 includes a second light-shielding metal layer BM2 and a second metal oxide layer OX2 disposed on the second light-shielding metal layer BM2. In some embodiments, the length L2 of the second light-transmitting region LT2 is greater than or equal to the length L1 of the first light-transmitting region LT1.

[0119] Please see Figure 1 Multiple microlenses LN are disposed on the second light-shielding part 160, wherein individual microlenses LN correspond to individual second light-transmitting areas LT2 (for example, the center point of individual second light-transmitting areas LT2 is located on the vertical bisector of individual microlenses LN).

[0120] In some implementations, the imaging of reflected light can be adjusted by changing the radius of curvature of the microlens LN and the position of the protrusion LNa of the microlens LN (e.g., amplifying external light signals via the microlens LN), thereby obtaining a fingerprint image of the finger.

[0121] Cover plate 170 is disposed on microlens LN, for example Figure 1 In the middle, the microlens LN is directly connected to the cover plate 170.

[0122] In some embodiments, the cover plate 170 includes at least one of a protective plate, a touch panel, and a display panel to provide the function of protecting the microlens LN, or the function of touch control, or even the function of displaying an image.

[0123] Next, please see Figure 5A as well as Figure 5B . Figure 5A A cross-sectional schematic diagram illustrating the travel of light (e.g., reflected light RL and stray light SL) in a biometric identification device 100 in some embodiments of this disclosure. Figure 5B Show Figure 5A Top view of the first light-shielding part 150 in the middle section.

[0124] exist Figure 5A In this equation, the distance between the center points of adjacent individual second light-transmitting areas LT2 is defined as distance P, the length of individual second light-transmitting areas LT2 is length L2, the length of the interval area SP is length S0, the length of the first light-transmitting area LT1 is length L1, the vertical length from the outline edge of the first light-blocking area BR1 to the outline edge of the first light-transmitting area LT1 is vertical length L', and the length of the light range (or the light range of the reflected light RL) projected onto the individual photosensitive element SR through the individual microlens LN is length L0. In equation 1: P Under the premise that -L2>S0 (the length of an individual second light-shielding area BR2 is greater than the length S0 of the spacer area SP, where the relationship for length S0 is P-L1-2L'=S0) and the relationship 3: L1+2L'>L0 (the length of an individual first light-shielding part 150 is greater than the length L0 of the light range projected by an individual microlens LN onto an individual photosensitive element SR), stray light SL (e.g., light with an incident angle greater than the maximum incident angle θ of the reflected light RL) can be prevented from entering the photosensitive element SR through the spacer area SP. That is, by designing the element length and distance that conform to the relationships 1 to 3, interference from stray light SL entering through the spacer area SP can be avoided, improving the accuracy of fingerprint signal detection, while retaining the spacer area SP and reducing the parasitic capacitance between the first light-shielding area BR1 and the dielectric layer 142.

[0125] In some embodiments, the length S0 of the spacer SP ranges from 10 micrometers ≥ S ≥ 2.5 micrometers. In some embodiments, the vertical length L' from the outline edge of the first light-shielding area BR1 to the outline edge of the first light-transmitting area LT1 ranges from 10 micrometers ≥ vertical length L' ≥ 2.5 micrometers.

[0126] In some embodiments, the length L2 of an individual second light-transmitting region LT2 ranges from 10 micrometers to 2.5 micrometers. In some embodiments, the length L1 of the first light-transmitting region LT1 ranges from 8 micrometers to 2.5 micrometers. In some embodiments, the length L0 of the light range projected onto an individual photosensitive element SR via an individual microlens LN ranges from 10 micrometers to 2.5 micrometers.

[0127] Figure 5A In the middle, the upper surface of the photosensitive element SR reaches the dielectric layer 142 ( Figure 5A Dielectric layer 142 is omitted in the text; dielectric layer 142 can be referenced. Figure 1The distance from the upper surface of dielectric layer 142 to dielectric layer 144 is distance H0. Figure 5A Dielectric layer 144 is omitted in the text; dielectric layer 144 can be referenced. Figure 1 The distance from the upper surface of dielectric layer 144 to cover plate 170 is distance H1, and the distance from the upper surface of dielectric layer 144 to cover plate 170 is distance H2. Based on the principle that the side lengths of a triangle are proportional when the triangles are equal in angle (see triangles B3 and B4 for example), the relationships between distances H0 and H1 and lengths L', S0, P, and L1 are (for example) The thickness of the first shading region BR1 and the second shading region BR2 is extremely thin and can be ignored here. Substituting these into equations 1 to 3 (Equation 1: L1 + 2L' > ​​L0, Equation 2: P - L1 - 2L' = S0, and Equation 3: P - L2 > S0), we obtain equation 4 after simplification.

[0128]

[0129] Since the first light-shielding region BR1 is directly disposed on the dielectric layer 142, therefore, in Figure 5A In this context, the upper surface of dielectric layer 142 can also be understood as the lower surface of the first light-shielding region BR1. Furthermore, since the second light-shielding region BR2 is directly disposed on dielectric layer 144, therefore, in Figure 5A In this context, the upper surface of dielectric layer 144 can also be understood as the lower surface of the second light-shielding region BR2.

[0130] In some embodiments, the upper surface of the photosensitive element SR extends to the dielectric layer 142. Figure 5A The distance H0 (or the distance from the upper surface of the photosensitive element SR to the lower surface of the first light-shielding area BR1, not shown) is in the range of 6 micrometers ≥ distance H0 ≥ 2 micrometers. In some embodiments, the dielectric layer 142 ( Figure 5A The upper surface of (not shown) to dielectric layer 144 ( Figure 5A The distance H1 (or the distance from the lower surface of the first shading area BR1 to the lower surface of the second shading area BR2) is 30 micrometers ≥ distance H1 ≥ 5 micrometers.

[0131] In one embodiment, when the length L1 is 4 micrometers, the length L2 is 6.5 micrometers, the vertical length L' is 5 micrometers, the distance H0 is 5 micrometers, and the distance H1 is 10 micrometers (and the length S0 is 2.9 micrometers derived from relation 2), it can satisfy relations 1 to 4 and achieve the technical effect of blocking stray light SL from incident on the photosensitive element SR.

[0132] In some other embodiments, the microlens LN of the biometric identification device 100 may also be configured in different ways.

[0133] For example, please see Figure 6A , Figure 6A This diagram shows a cross-sectional view of the biometric identification device 200 in some other embodiments of the present disclosure. Figure 6A and Figure 1 The component configurations are basically similar, the difference lies in, Figure 6A The microlens LN is connected to the cover plate 270 via an adhesive layer 280. In some embodiments, the adhesive layer 280 is a transparent optical adhesive.

[0134] In some other embodiments, the microlens LN can be disposed on the second light-shielding portion 260 with the convex portion facing upwards. In some embodiments, an insulating layer can be selectively added between the microlens LN and the second light-shielding portion 260.

[0135] For example, please see Figure 6B , Figure 6B This diagram shows a cross-sectional view of the biometric identification device 300 in some other embodiments of the present disclosure. Figure 6B and Figure 1 The component configurations are basically similar, the difference lies in, Figure 6B A single microlens LN is disposed on multiple second light-shielding portions 360, wherein the orthogonal projection range of the second light-transmitting area LT2 onto the substrate 310 is located within the orthogonal projection range of the microlens LN onto the substrate 310, that is, a single microlens LN corresponds to multiple second light-transmitting areas LT2.

[0136] Some embodiments of this disclosure provide a biometric identification device that, by separating at least one group of adjacent first light-shielding portions, prevents the first light-shielding portions from extending and covering the entire dielectric layer, reduces parasitic capacitance generated by the contact between the first light-shielding area in the first light-shielding portion and the dielectric layer, thereby reducing interference from stray capacitance, improving the response of biometric signals, and thus improving the detection accuracy of biometrics.

[0137] Although this disclosure has been disclosed above with multiple implementation methods and embodiments, it is not intended to limit the content of this disclosure. Any person skilled in the art can make various changes and modifications without departing from the concept and scope of this disclosure. Therefore, the scope of protection of this disclosure shall be determined by the claims.

Claims

1. A biometric identification device, comprising: a substrate; a plurality of light sensing elements disposed on the substrate; a first dielectric layer disposed on the light sensing elements; a plurality of first light shielding portions disposed on the first dielectric layer, wherein each of the first light shielding portions has a first light transmission region and a first light shielding region surrounding the first light transmission region, the first light transmission region corresponds to and overlaps with each of the light sensing elements, and at least two of the first light shielding portions are separated by a spacing region; a second dielectric layer disposed on the first light shielding portions; and a second light shielding portion disposed on the second dielectric layer, wherein the second light shielding portion has a plurality of second light transmission regions and a second light shielding region between two adjacent second light transmission regions, each of the second light transmission regions corresponds to each of the first light transmission regions, and at least part of the projection range of the spacing region on the substrate is within the projection range of the second light shielding region on the substrate, the biometric identification device further comprises an active element, the active element is connected to the light sensing elements, the light sensing elements are disposed on a first electrode layer, the light sensing elements are electrically connected to the active element through the first electrode layer, and the first light transmission region and the spacing region overlap with the first electrode layer. 2.The biometric identification device of claim 1, wherein each of the first light shielding portions is separated by the spacing region. 3.The biometric identification device of claim 1, wherein part of the first light shielding portions are connected via the first light shielding region. 4.The biometric identification device of claim 1, wherein the first light shielding region is made of metal. 5.The biometric identification device of claim 4, wherein the length of the first light transmission region ranges from 2.5 microns to 5 microns. 6.The biometric identification device of claim 1, wherein the profile shape of the first light shielding portion in a top view comprises a circle, a square, a pentagon, a hexagon, or an octagon.

7. The biometric device of claim 1, further comprising at least one microlens disposed above the second light blocking portion. wherein P is the distance between the center points of adjacent second light transmission regions, L2 is the length of each second light transmission region, S0 is the length of the spacing region, L1 is the length of the first light transmission region, L’ is the vertical length from the profile edge of the first light shielding region to the profile edge of the first light transmission region, L0 is the length of a light ray range projected on each light sensing element by the at least one microlens, then P-L2>S0; P-L1-2L’=S0; and L1+2L’>L0.

8. The biometric device of claim 1, further comprising at least one microlens disposed above the second light blocking portion. wherein P is the distance between the center points of adjacent second light transmission regions, L2 is the length of each second light transmission region, S0 is the length of the spacing region, L1 is the length of the first light transmission region, L’ is the vertical length from the profile edge of the first light shielding region to the profile edge of the first light transmission region, L0 is the length of a light ray range projected on each light sensing element by the at least one microlens, H0 is the distance from the upper surface of each light sensing element to the upper surface of the first dielectric layer, and H1 is the distance from the upper surface of the first dielectric layer to the upper surface of the second dielectric layer, then 9.The biometric identification device of claim 7 or 8, wherein the length S0 of the spacing region ranges from 10 microns≥S0≥2.5 microns; and A vertical length L' of a profile edge of the first light-shielding region to a profile edge of the first light-transmitting region ranges from 10 micrometers ≥ L' ≥ 2.5 micrometers.

10. The biometric device of claim 7 or 8, wherein, A length L2 of each of the second light-transmitting regions ranges from 10 micrometers ≥ L2 ≥ 2.5 micrometers; A length L1 of the first light-transmitting region ranges from 8 micrometers ≥ L1 ≥ 2.5 micrometers; A length L0 of the light ray range ranges from 10 micrometers ≥ L0 ≥ 2.5 micrometers; A distance H0 from an upper surface of the photosensitive element to an upper surface of the first dielectric layer ranges from 6 micrometers ≥ H0 ≥ 2 micrometers; and A distance H1 from an upper surface of the first dielectric layer to an upper surface of the second dielectric layer ranges from 30 micrometers ≥ H1 ≥ 5 micrometers.

11. The biometric device of claim 1, wherein, The first light-shielding region includes a first light-shielding metal layer and a first metal oxide layer disposed on the first light-shielding metal layer.

12. The biometric device of claim 1, wherein, The second light-shielding region includes a second light-shielding metal layer and a second metal oxide layer disposed on the second light-shielding metal layer.

13. The biometric device of claim 1, further comprising a microlens disposed on the second light-shielding portion, wherein the second light-transmitting regions are located within a range of a normal projection of the microlens on the substrate.

14. The biometric device of claim 1, further comprising a plurality of microlenses disposed on the second light-shielding portion, wherein each of the microlenses corresponds to each of the second light-transmitting regions.

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