TWI798974B - Photosensitive device - Google Patents

Abstract

A photosensitive device includes a first substrate, a second substrate, a supporting structure, first microlenses, second microlenses, a first photosensitive element, a second photosensitive element, and a collimating structure. The second substrate is opposite to the first substrate, and there is a gap between the first substrate and the second substrate. The supporting structure is located in the gap between the first substrate and the second substrate. The first microlenses and the second microlenses are respectively disposed on the first side and the second side of the gap. The first photosensitive element is overlapping with one of the first microlenses and one of the second microlenses. The second photosensitive element is overlapping with another one of the second microlenses. The collimating structure is located between the first substrate and the first microlenses.

Description

photosensitive device

The present invention relates to a photosensitive device, and more particularly to a photosensitive device with microlenses.

In order to increase the screen-to-body ratio of the display to achieve a narrow bezel design, under-display fingerprint sensing technology has become a trend. To put it simply, the under-display fingerprint sensing technology is to dispose the photosensitive device under the display panel of the electronic device. After the electronic device detects that the user touches the display screen, the electronic device controls the display panel to emit light to illuminate the surface of the user's finger. The sensing light will be (diffusely) reflected by the user's finger into the photosensitive device under the display panel, and the reflected light will be concentrated on the photosensitive element through multiple microlenses and collimating structures to convert it into a digital image signal, which can be obtained User fingerprint image.

Generally speaking, if a color image is to be recognized, photosensitive elements for receiving light of different wavelengths are generally required to be disposed in the photosensitive device. However, in the same material, different wavelengths of light will have different refractive indices. Specifically, the longer the wavelength of light, the smaller the refractive index in the medium. Therefore, different colors of light will have different focal depths in the photosensitive device, and the image recognition and light collection ability of the photosensitive device will be reduced. worse.

The invention provides a photosensitive device with good image sensing quality.

At least one embodiment of the present invention provides a photosensitive device, which includes a first substrate, a second substrate, a support structure, a plurality of first microlenses, a plurality of second microlenses, a first photosensitive element, a second photosensitive element, and a quasi- straight structure. The second substrate is arranged opposite to the first substrate, and there is a gap between the first substrate and the second substrate. The supporting structure is located in the gap between the first substrate and the second substrate. The first microlens and the second microlens are respectively disposed on the first side and the second side of the gap. The first photosensitive element overlaps one of the first microlenses and one of the second microlenses. The second photosensitive element is overlapped with the other one of the second microlenses. The collimation structure is located between the first substrate and the first microlens.

At least one embodiment of the present invention provides a photosensitive device, which includes a first substrate, a second substrate, a plurality of first microlenses, a plurality of second microlenses, a first photosensitive element, and a second photosensitive element. The second substrate is arranged opposite to the first substrate, and there is a gap between the first substrate and the second substrate. The first microlens and the second microlens are respectively disposed on the first side and the second side of the gap. The material of the first microlens is different from that of the second microlens and/or the radius of curvature of the first microlens is different from that of the second microlens. The first photosensitive element overlaps one of the first microlenses. The second photosensitive element overlaps one of the second microlenses and does not overlap the first microlens.

As used herein, "about," "approximately," "essentially," or "essentially" includes the stated value and averages within acceptable deviations from the particular value as determined by one of ordinary skill in the art, taking into account the The measurement in question and the specific amount of error associated with the measurement (ie, the limitations of the measurement system). For example, "about" can mean within one or more standard deviations of the stated value, or for example within ±30%, ±20%, ±15%, ±10%, ±5%. Furthermore, "about", "approximately", "essentially" or "substantially" used herein can choose a more acceptable deviation range or standard deviation according to the nature of measurement, cutting or other properties, and can be Not one standard deviation applies to all properties.

In the drawings, the thickness of layers, films, panels, regions, etc., are exaggerated for clarity. It will be understood that when an element such as a layer, film, region, or substrate is referred to as being "on" or "connected to" another element, it can be directly on or connected to the other element, or Intermediate elements may also be present. In contrast, when an element is referred to as being "directly on" or "directly connected to" another element, there are no intervening elements present. As used herein, "connected" may refer to physical and/or electrical connection. Furthermore, "electrically connected" may mean that other elements exist between two elements.

Reference will now be made in detail to the exemplary embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and descriptions to refer to the same or like parts.

FIG. 1 is a schematic cross-sectional view of a display device according to an embodiment of the present invention. FIG. 2 is a partially enlarged schematic view of the photosensitive device of FIG. 1 .

Referring to FIG. 1 and FIG. 2 , the display device 10 includes a photosensitive device 100 , a display panel 200 and a cover plate 250 that are stacked on top of each other. For example, the photosensitive device 100 and the display panel 200 are bonded together by an optical adhesive layer 220 distributed across the entire surface. The material of the optical adhesive layer 220 includes, for example, optical clear resin (OCR), optical clear adhesive (OCA), pressure sensitive adhesive (PSA), or other suitable adhesive materials.

In this embodiment, the photosensitive device 100 may be disposed on the back side of the display panel 200 . For example, the photosensitive device 100 is a fingerprint recognition module, and the display device 10 may be a fingerprint recognition (Fingerprint on display) device, but the present invention is not limited thereto.

The display panel 200 is, for example, an organic light emitting diode (organic light emitting diode, OLED) panel, a micro light emitting diode (micro-LED) panel, a submillimeter light emitting diode (mini light emitting diode, mini -LED) panels, or other suitable self-illuminating display panels. It is particularly noted that, in this embodiment, the display panel 200 can also be used as an illumination light source for fingerprint recognition. However, the present invention is not limited thereto. In other embodiments, the display panel may also be a non-self-illuminating display panel (such as a liquid crystal display panel), and the display device uses a backlight source to provide illumination light required for fingerprint recognition.

The photosensitive device 100 includes a first substrate 101 , a second substrate 102 , a support structure 180 , a plurality of first microlenses ML1 , a plurality of second microlenses ML2 , a photosensitive element layer PSL, and a first collimation structure CM1 . In this embodiment, the photosensitive device 100 further includes a second collimation structure CM2, a third collimation structure CM3, a light-shielding pattern layer LS, a first filter element 191, a second filter element 192, and a third filter element 193 .

The first substrate 101 includes a transparent or opaque substrate. For example, the first substrate 101 includes glass, quartz, organic polymer, or opaque/reflective material (for example: conductive material, metal, wafer, ceramic or other applicable materials) or other applicable Material. If conductive materials or metals are used, an insulating layer (not shown) is covered on the first substrate 101 to avoid short circuit problems.

The photosensitive element layer PSL is located above the first substrate 101 and includes a plurality of active elements and a plurality of photosensitive elements. In FIG. 1 , the first photosensitive element 112 , the second photosensitive element 114 and the third photosensitive element 116 in the photosensitive element layer PSL are shown, and the illustration of the electrical connection to the first photosensitive element 112 and the second photosensitive element is omitted. 114 and a plurality of active elements of the third photosensitive element 116 . In some embodiments, the first photosensitive element 112 , the second photosensitive element 114 and the third photosensitive element 116 are formed together, and the first photosensitive element 112 , the second photosensitive element 114 and the third photosensitive element 116 are all connected with the first photosensitive element 112 . There is the same vertical distance between the substrates 101 . In other words, in some embodiments, based on the surface of the first substrate 101 , the first photosensitive element 112 , the second photosensitive element 114 and the third photosensitive element 116 are located at the same level.

The first photosensitive element 112 , the second photosensitive element 114 and the third photosensitive element 116 are respectively electrically connected to corresponding active elements. In order to illustrate the electrical connection between the photosensitive element and the active element, FIG. 2 takes the first photosensitive element 112 as an example for illustration, and the second photosensitive element 114 and the third photosensitive element 116 are also electrically connected to the corresponding active components.

Please refer to FIG. 2 , the first photosensitive element 112 (or the second photosensitive element 114 or the third photosensitive element 116 ) is electrically connected to the active element T. Referring to FIG. The active element T has a source SE, a drain DE, a gate GE and a semiconductor pattern SC. In this embodiment, the semiconductor pattern SC is a single-layer or multi-layer structure, which includes amorphous silicon, polycrystalline silicon, microcrystalline silicon, single crystal silicon, organic semiconductor materials, oxide semiconductor materials (for example: indium zinc oxide, indium gallium Zinc oxide or other suitable materials, or a combination of the above materials) or other suitable materials or a combination of the above materials, but the present invention is not limited thereto. The semiconductor pattern SC is located on the first substrate 101 . In this embodiment, a buffer layer 110 is selectively disposed between the semiconductor pattern SC and the first substrate 101 . The gate GE overlaps the semiconductor pattern SC, and a gate insulating layer 120 is sandwiched between the semiconductor pattern SC. In this embodiment, the gate GE can be selectively disposed above the semiconductor pattern SC to form a top-gate thin film transistor, but the invention is not limited thereto. In other embodiments, the gate GE may also be disposed under the semiconductor pattern SC to form a bottom-gate TFT. The interlayer insulating layer 130 is located on the gate GE and the gate insulating layer 120 . The source SE and the drain DE are located on the interlayer insulating layer 130 and are electrically connected to the semiconductor pattern SC.

The planarization layer 140 is on the insulating interlayer 130 . The first photosensitive element 112 (or the second photosensitive element 114 or the third photosensitive element 116 ) is located on the interlayer insulating layer 130 and is electrically connected to the drain DE of the active device T. As shown in FIG. In this embodiment, the first photosensitive element 112 (which may also be the second photosensitive element 114 or the third photosensitive element 116 ) includes a first electrode E1 , a photoelectric conversion layer PCL and a second electrode E2 . The photoelectric conversion layer PCL has a single-layer structure or a multi-layer structure. For example, the photoelectric conversion layer PCL is, for example, silicon-rich oxide (SRO). In other embodiments, the photoelectric conversion layer PCL is a stacked layer of a P-type semiconductor, an intrinsic semiconductor, and an N-type semiconductor. The planarization layer 150 is located on the second electrode E2.

Please continue to refer to FIG. 1 , the first collimation structure CM1 , the second collimation structure CM2 and the third collimation structure CM3 are located above the first substrate 101 . The first collimation structure CM1 has a plurality of first holes CM1a corresponding to the photosensitive elements (including the first photosensitive element 112 , the second photosensitive element 114 and the third photosensitive element 116 ), and the second collimation structure CM2 has a plurality of first holes CM1a corresponding to the photosensitive elements. A plurality of second holes CM2a, and the third collimation structure CM3 has a plurality of third holes CM3a corresponding to the photosensitive element. The first hole CM1a, the second hole CM2a and the third hole CM3a overlap in the direction Z. In this embodiment, the holes can be arranged in an array, for example, arranged in multiple columns and rows along the direction X and the direction Y respectively, but not limited thereto.

In this embodiment, the flat layer 162 is located on the photosensitive element layer PSL, and the first collimation structure CM1 is located on the flat layer 162 . The planarization layer 164 is located on the first collimation structure CM1 , and the second collimation structure CM2 is located on the planarization layer 164 . The planarization layer 166 is located on the second collimation structure CM2 , and the third collimation structure CM3 is located on the planarization layer 166 .

The first microlens ML1 is disposed on the first substrate 101 . The first collimation structure CM1 and the second collimation structure CM2 are located between the first substrate 101 and the first microlens ML1 .

In this embodiment, the first microlenses ML1 may be arranged in multiple columns and rows along the direction X and the direction Y. In this embodiment, part of the third hole CM3a is provided with the first microlens ML1, while another part of the third hole CM3a is not provided with the first microlens ML1. Therefore, in this embodiment, some photosensitive elements (such as the first photosensitive element 112 and the third photosensitive element 116 ) overlap the first microlens ML1 in the direction Z, and some photosensitive elements (such as the second photosensitive element 114 ) The direction Z does not overlap with the first microlens ML1.

In some embodiments, the first microlens ML1 may be made of organic photoresist material, but the invention is not limited thereto.

The second substrate 102 is opposite to the first substrate 101 . The second substrate 102 includes a transparent substrate. For example, the second substrate 102 includes glass, quartz, organic polymer or other applicable materials.

The light-shielding pattern layer LS is disposed on the second substrate 102 . For example, the light-shielding pattern layer LS is disposed between the second substrate 102 and the first substrate 101 . The light-shielding pattern layer LS has a plurality of holes LSa. In this embodiment, the hole LSa of the light-shielding pattern layer LS overlaps the first hole CM1a, the second hole CM2a and the third hole CM3a in the direction Z.

The first filter element 191 , the second filter element 192 and the third filter element 193 are disposed on the second substrate 102 . For example, the first filter element 191 , the second filter element 192 and the third filter element 193 are disposed between the second substrate 102 and the first substrate 101 , and are respectively filled into the corresponding holes LSa.

The first filter element 191 overlaps the first photosensitive element 112 and is configured to pass the light L1 having the first wavelength λ1. The second filter element 192 overlaps the second photosensitive element 114 and is configured to pass the light L2 having the second wavelength λ2. The third filter element 193 overlaps the third photosensitive element 116 and is configured to pass the light L3 having the third wavelength λ3.

In this embodiment, the first wavelength λ1 is greater than the third wavelength λ3, and the third wavelength λ3 is greater than the second wavelength λ2, but the present invention is not limited thereto. In other embodiments, the first wavelength λ1 is greater than the second wavelength λ2, and the second wavelength λ2 is greater than the third wavelength λ3. In some embodiments, the light L1 , the light L2 and the light L3 are visible light, such as green light, blue light and red light, but the invention is not limited thereto. In other embodiments, the light L1 , the light L2 and the light L3 may also include non-visible light, such as infrared light.

In some embodiments, the first filter element 191 , the second filter element 192 and the third filter element 193 are provided to convert the light into light with a predetermined wavelength, but the present invention is not limited thereto. In other embodiments, the first filter element 191 , the second filter element 192 and the third filter element 193 are not required, and light with a predetermined wavelength is obtained by selecting a light source capable of emitting light with a predetermined wavelength.

The cladding layer 171 is disposed on the first filter element 191 , the second filter element 192 and the third filter element 193 .

The second microlens ML2 is disposed on the second substrate 102 . At least one of the first filter element 191 , the second filter element 192 and the third filter element 193 is located between the second substrate 102 and the second microlens ML2 .

In this embodiment, the second microlenses ML2 may be arranged in multiple columns and rows along the direction X and the direction Y. In this embodiment, part of the photosensitive elements (such as the second photosensitive element 114 and the first photosensitive element 112 ) overlap the second microlens ML2 in the direction Z, and part of the photosensitive elements (such as the third photosensitive element 116 ) overlap the second microlens ML2 in the direction Z. does not overlap the second microlens ML2.

In some embodiments, the second microlens ML2 may be made of organic photoresist material, but the invention is not limited thereto.

In this embodiment, there is a gap GP between the first substrate 101 and the second substrate 102 , wherein the gap GP is, for example, an air gap. The support structure 180 is located in the gap GP between the first substrate 101 and the second substrate 102 , that is to say, the thickness of the gap GP between the first substrate 101 and the second substrate 102 is defined by the thickness of the support structure 180 . In this embodiment, the supporting structure 180 is used to support the gap GP between the first substrate 101 and the second substrate 102 to prevent the gap GP between the first substrate 101 and the second substrate 102 from collapsing.

In some embodiments, the height 180h of the supporting structure 180 is greater than or equal to the sum of the height h1 of the first microlens ML1 and the height h2 of the second microlens ML2 , but the invention is not limited thereto. In other embodiments, a dummy first microlens ML1 is provided under the support structure 180, and the support structure 180 is located on the dummy first microlens ML1. At this time, the height 180h of the support structure 180 is greater than or equal to the second The height h2 of the microlens ML2. In some embodiments, the thickness of the third collimation structure CM3 is relatively thin and thus can be omitted.

The first microlens ML1 and the second microlens ML2 are respectively disposed on the first side S1 and the second side S2 of the gap GP. In this embodiment, the first side S1 of the gap GP is a side of the gap GP close to the first substrate 101 , and the second side S2 is a side of the gap GP close to the second substrate 102 . In other words, the first microlens ML1 is disposed on a side of the gap GP close to the first substrate 101 , and the second microlens ML2 is disposed on a side of the gap GP close to the second substrate 102 . In other embodiments, the positions of the first microlens ML1 and the second microlens ML2 may be reversed.

In this embodiment, the first photosensitive element 112 overlaps one of the first microlens ML1 and one of the second microlens ML2 in the direction Z. The second photosensitive element 114 overlaps one of the second microlenses ML2 in the direction Z and does not overlap the first microlens ML1 . The third photosensitive element 116 overlaps one of the first microlenses ML1 in the direction Z and does not overlap the second microlens ML2 .

In this embodiment, the first microlens ML1 and the second microlens ML2 are convex lenses, and the focus of the convex lenses can be calculated by formula 1. Formula 1

In Formula 1, f is the focal length of the microlens, n is the refractive index, and R is the radius of curvature of the microlens.

In this embodiment, the light L1 , the light L2 and the light L3 each have different wavelengths. The longer the wavelength of light, the smaller the refractive index n in the medium, and the easier it is to focus on a deeper position. In this embodiment, the radius of curvature R1 of the first microlens ML1 is different from the radius of curvature R2 of the second microlens ML2 to prevent the light L1 and the light L2 from focusing at different depth positions. Specifically, in this embodiment, the third wavelength λ3 of the light L3 is greater than the second wavelength λ2 of the light L2, therefore, when the material of the first microlens ML1 is the same as that of the second microlens ML2, the light L3 is The refractive index n3 in the first microlens ML1 is smaller than the refractive index n2 of the light ray L2 in the second microlens ML2. By making the radius of curvature R2 of the second microlens ML2 larger than the radius of curvature R1 of the first microlens ML1, the problem that the focal position of the light L3 is deeper than the focal position of the light L2 caused by the refractive index n3 being smaller than the refractive index n2 can be improved . In this embodiment, the light L3 passing through the first microlens ML1 is focused on the position of the third photosensitive element 116 , and the light L2 passing through the second microlens ML2 is focused on the position of the second photosensitive element 114 .

In addition, when the first microlens ML1 and the second microlens ML2 are combined, the focus can be calculated by formula 2. Formula 2

In formula 2, f is the focal length of the combination of the first microlens ML1 and the second microlens ML2, f1 is the focal length of the first microlens ML1, f2 is the focal length of the second microlens ML2, and d is the first The vertical distance between the microlens ML1 and the second microlens ML2. In this embodiment, d is much smaller than f1 and f2 or even d is equal to 0, therefore, d/f ₁ f ₂ approaches 0. For example, d is less than 1 micron, and f1 and f2 are respectively 10 microns to 25 microns. Therefore, Equation 2 can be further omitted to become Equation 3. Formula 3

In this embodiment, the first wavelength λ1 of the light L1 is greater than the third wavelength λ3 of the light L3 and the second wavelength λ2 of the light L2. Therefore, when the material of the first microlens ML1 is the same as that of the second microlens ML2 , the refractive index n1 of the ray L1 in the first microlens ML1 or the second microlens ML2 is smaller than the refractive index n3 of the ray L3 in the first microlens ML1 and the refractive index n2 of the ray L2 in the second microlens ML2. By making the first microlens ML1 and the second microlens ML2 overlap together, the problem of too deep focus of the light L1 caused by the first wavelength λ1 being greater than the third wavelength λ3 and the second wavelength λ2 is improved. In this embodiment, the light L1 passing through the first microlens ML1 and the second microlens ML2 is focused on the position of the first photosensitive element 112 .

Based on the above, by setting the first microlens ML1 and the second microlens ML2, the light L1, the light L2 and the light L3 can be focused on the first photosensitive element 112, the second photosensitive element 114 and the third photosensitive element 116 respectively. position, thereby improving the quality of image sensing. In addition, all the first microlenses ML1 are formed on the same layer by the same process, and all the second microlenses ML2 are formed on another same layer by the same process. In other words, in this embodiment, the first microlens ML1 and the second microlens ML2 with different curvature radii are respectively formed in different layers, compared to the first microlens ML1 and the second microlens ML1 with different curvature radii formed in the same layer. The microlens ML2 may have lower manufacturing costs.

In addition, although in FIG. 1 , the photosensitive device 100 is configured to receive light L1 , light L2 and light L3 with three different wavelengths, the present invention is not limited thereto. In other embodiments, the photosensitive device is configured to receive at least two of the light L1 , the light L2 and the light L3 . In other words, in other embodiments, the arrangement method of the microlens includes that the photosensitive element overlaps the first microlens ML1 and the second microlens ML2 at the same time, the photosensitive element only overlaps the first microlens ML1, and the photosensitive element only overlaps the second microlens ML1. At least two of the two microlenses ML2. In other words, the present invention does not limit the photosensitive device 100 to have a photosensitive element that overlaps the first microlens ML1 and the second microlens ML2 at the same time, a photosensitive element that only overlaps the first microlens ML1, and a photosensitive element that only overlaps the second microlens ML1. These three characteristics of microlens ML2.

FIG. 3 is a schematic cross-sectional view of a display device according to an embodiment of the present invention. It must be noted here that the embodiment in FIG. 3 uses the component numbers and parts of the content in the embodiment in FIG. 1 , wherein the same or similar numbers are used to denote the same or similar components, and the description of the same technical content is omitted. For the description of the omitted part, reference may be made to the foregoing embodiments, and details are not repeated here.

The difference between the display device 20 of FIG. 3 and the display device 10 of FIG. 1 is that: in the display device 20, the curvature radius R1 of the first microlens ML1 is equal to the curvature radius R2 of the second microlens ML2, and the curvature radius R2 of the first microlens ML1 The material is different from that of the second microlens ML2.

In some embodiments, adjusting the material of the first microlens ML1 increases the refractive index n3' of the light L3 in the first microlens ML1 (for example, it is greater than the refractive index of the light L3 in the first microlens ML1 in the display device 10 n3). In other embodiments, adjusting the material of the second microlens ML2 reduces the refractive index n2' of the light L2 in the second microlens ML2 (for example, it is smaller than the refractive index of the light L2 in the second microlens ML2 in the display device 10 n2). In some embodiments, the material of the first microlens ML1 and the material of the second microlens ML2 are adjusted simultaneously.

In this embodiment, under the light of the same wavelength, the refractive index of the first microlens ML1 is greater than the refractive index of the second microlens ML2, and the refractive index of the longer wavelength light L3 in the first microlens ML1 is about It is equal to the refractive index of light L2 with shorter wavelength in the second microlens ML2. Based on this, the problem that the depth of focus of the light L1 is deeper than the depth of focus of the light L2 caused by the third wavelength λ3 being greater than the second wavelength λ2 can be improved.

In addition, although in FIG. 3 , the photosensitive device 100 is configured to receive light L1 , light L2 and light L3 with three different wavelengths, the present invention is not limited thereto. In other embodiments, the photosensitive device is configured to receive at least two of the light L1 , the light L2 and the light L3 . In other words, in other embodiments, the arrangement method of the microlens includes that the photosensitive element overlaps the first microlens ML1 and the second microlens ML2 at the same time, the photosensitive element only overlaps the first microlens ML1, and the photosensitive element only overlaps the second microlens ML1. At least two of the two microlenses ML2. In other words, the present invention does not limit the photosensitive device 100 to have a photosensitive element that overlaps the first microlens ML1 and the second microlens ML2 at the same time, a photosensitive element that only overlaps the first microlens ML1, and a photosensitive element that only overlaps the second microlens ML1. These three characteristics of microlens ML2.

FIG. 4 is a schematic cross-sectional view of a display device according to an embodiment of the present invention. It must be noted here that the embodiment in FIG. 4 follows the component numbers and partial content of the embodiment in FIG. 1 , wherein the same or similar numbers are used to denote the same or similar components, and the description of the same technical content is omitted. For the description of the omitted part, reference may be made to the foregoing embodiments, and details are not repeated here.

The difference between the display device 30 of FIG. 4 and the display device 10 of FIG. 1 is that: in the display device 30, the first side S1 of the gap GP provided with the first microlens ML1 is the side of the gap GP close to the second substrate 102, and The second side S2 of the gap GP provided with the second microlens ML2 is a side of the gap GP close to the first substrate 101 .

In this embodiment, the first microlens ML1 is disposed on the second substrate 102 , and the second microlens ML2 is disposed on the first substrate 101 .

In this embodiment, the curvature radius R1 of the first microlens ML1 is smaller than the curvature radius R2 of the second microlens ML2. In this embodiment, the material of the first microlens ML1 is the same as that of the second microlens ML2, but the invention is not limited thereto. In other embodiments, the material of the first microlens ML1 is different from that of the second microlens ML2.

In addition, although in FIG. 4 , the photosensitive device 100 is configured to receive light L1 , light L2 and light L3 with three different wavelengths, the present invention is not limited thereto. In other embodiments, the photosensitive device is configured to receive at least two of the light L1 , the light L2 and the light L3 . In other words, in other embodiments, the arrangement method of the microlens includes that the photosensitive element overlaps the first microlens ML1 and the second microlens ML2 at the same time, the photosensitive element only overlaps the first microlens ML1, and the photosensitive element only overlaps the second microlens ML1. At least two of the two microlenses ML2. In other words, the present invention does not limit the photosensitive device 100 to have a photosensitive element that overlaps the first microlens ML1 and the second microlens ML2 at the same time, a photosensitive element that only overlaps the first microlens ML1, and a photosensitive element that only overlaps the second microlens ML1. These three characteristics of microlens ML2.

FIG. 5 is a schematic cross-sectional view of a display device according to an embodiment of the present invention. It must be noted here that the embodiment in FIG. 5 follows the component numbers and part of the content of the embodiment in FIG. 1 , wherein the same or similar numbers are used to denote the same or similar components, and the description of the same technical content is omitted. For the description of the omitted part, reference may be made to the foregoing embodiments, and details are not repeated here.

The difference between the display device 40 in FIG. 5 and the display device 10 in FIG. 1 is that in the display device 40, the first photosensitive element 112 overlaps one of the first microlens ML1 and one of the second microlens ML2, In the combination of the first microlens ML1 and the second microlens ML2 overlapping the first photosensitive element 112, the vertical distance d between the first microlens ML1 and the second microlens ML2 is equal to the focal length f1 of the first microlens ML1 Add the focal length f2 of the second microlens ML2.

In this embodiment, the first wavelength λ1 of the light L1 is greater than the second wavelength λ2 of the light L2. It can be known from Formula 2 that when the vertical distance d is equal to the focal length f1 plus the focal length f2, the combined focal length f of the first microlens ML1 and the second microlens ML2 is almost infinite. In other words, the combination of the first microlens ML1 and the second microlens ML2 can transform the light L1 into parallel light. In this embodiment, although the wavelength of the light L1 is too long, the microlens exceeds the process capability, and it is difficult to focus the light, but the combination of the first microlens ML1 and the second microlens ML2 can improve the convergence of the light L1, and Obtain collimation effect to improve image quality.

In this embodiment, the first microlens ML1 is closer to the first photosensitive element 112 than the second microlens ML2 . The focal length f2 of the second microlens ML2 is greater than the focal length f1 of the first microlens ML1, and the magnification (M) of the combination of the first microlens ML1 and the second microlens ML2 is equal to -f1/f2, and -f1/f2 is less than - 1. In this embodiment, the radius of curvature of the first microlens ML1 is the same as that of the second microlens ML2 , but the invention is not limited thereto. In other embodiments, the radius of curvature of the first microlens ML1 is different from the radius of curvature of the second microlens ML2. In this embodiment, the material of the first microlens ML1 is the same as that of the second microlens ML2, but the invention is not limited thereto. In other embodiments, the material of the first microlens ML1 is different from that of the second microlens ML2.

In some embodiments, the height 180h of the supporting structure 180 is approximately equal to the sum of the vertical distance d, the height h1 of the first microlens ML1 , and the height h2 of the second microlens ML2 , but the invention is not limited thereto. In other embodiments, a dummy first microlens ML1 is disposed under the support structure 180, and the support structure 180 is located on the dummy first microlens ML1. At this time, the height 180h of the support structure 180 is approximately equal to the vertical distance d and the height h2 of the second microlens ML2.

In addition, although in FIG. 5 , the second photosensitive element 114 overlaps the first microlens ML1 but not overlaps the second microlens ML2 , the present invention is not limited thereto. In other embodiments, the second photosensitive element 114 overlaps the second microlens ML2 but does not overlap the first microlens ML1 .

To sum up, in the photosensitive device of the present invention, the arrangement of the first microlens and the second microlens can improve the problem of different focal depths caused by inconsistent wavelengths of light, thereby improving the quality of image sensing.

FIG. 6 is a schematic cross-sectional view of a display device according to an embodiment of the present invention. It must be noted here that the embodiment in FIG. 6 follows the component numbers and part of the content of the embodiment in FIG. 1 , wherein the same or similar numbers are used to denote the same or similar components, and the description of the same technical content is omitted. For the description of the omitted part, reference may be made to the foregoing embodiments, and details are not repeated here.

Please refer to FIG. 6. In this embodiment, the first photosensitive element 112, the second photosensitive element 114, and the third photosensitive element 116 are respectively overlapped with one of the first microlens ML1 and one of the second microlens ML2. By.

In this embodiment, the first microlens ML1 and the second microlens ML2 have a first curvature radius R1 and a second curvature radius R2 respectively, and the first curvature radius R1 and the second curvature radius R2 may optionally be the same, but This is not the limit.

For example, the display device 50 can also be provided with a cover plate 250 on the side of the display panel 200 facing away from the photosensitive device 100 (or, the side of the second substrate 102 facing away from the first substrate 101), and the cover plate 250 has a surface away from the first substrate 101. The cover surface 250s of the second substrate 102 (or the display panel 200 ). The light-shielding pattern layer LS also has a surface LS1s facing the second substrate 102 . There is a distance D ₀ between the cover surface 250s of the cover 250 and the surface LS1s of the light-shielding pattern layer LS, and a distance _D1 between the surface 171s of the coating layer 171 and the surface LS1s of the light-shielding pattern layer LS. The hole LSa of the light-shielding pattern layer LS and the second microlens ML2 have a length L ₁ and a length L ₂ respectively along the arrangement direction (for example, the direction X). The second microlens ML2 also has a height h2 along a direction perpendicular to the arrangement.

，且孔洞LSa的長度L ₁可滿足以下關係式：

。 In a preferred embodiment, the second radius of curvature R2 of the second microlens ML2 can satisfy the following relationship:

, and the length L ₁ of the hole LSa can satisfy the following relationship:

.

On the other hand, the first collimation structure CM1 also has a surface CM1s facing the gap GP. In this embodiment, the planarization layer 166 is located on the surface CM1s of the first collimation structure CM1. Each of the first photosensitive element 112 to the third photosensitive element 116 has a light receiving surface 115rs facing the gap GP. There is a distance _D5 between the surface 166s of the flat layer 166 and the surface CM1s of the first collimation structure CM1, between the surface CM1s of the first collimation structure CM1 and the light receiving surfaces 115rs of the first photosensitive element 112 to the third photosensitive element 116 There is a distance D ₆ between them. The first microlens ML1 and the first hole CM1a respectively have a length L ₃ and a length L ₄ (ie, the aperture) along the arrangement direction (eg, the direction X). The first microlens ML1 also has a height h1 along a direction perpendicular to the arrangement. The first photosensitive element 112 to the third photosensitive element 116 have a length L ₅ along the direction X. The length L ₅ here is, for example, defined by the length along the direction X of the interface between the second electrode E2 of the first photosensitive element 112 to the third photosensitive element 116 and the photoelectric conversion layer PCL.

，且第一孔洞CM1a的長度L ₄可滿足以下關係式：

。 In a preferred embodiment, the first radius of curvature R1 of the first microlens ML1 can satisfy the following relationship:

, and the length L ₄ of the first hole CM1a can satisfy the following relationship:

.

It should be noted that a plurality of spacers 180 are also provided between the coating layer 171 and the flat layer 166, and these spacers 180, the surface 171s of the coating layer 171 and the surface 166s of the flat layer 166 are defined to accommodate these Microlens gap GP. More specifically, the first microlenses ML1 and the second microlenses ML2 are spaced apart from each other in the normal direction (eg, direction Z) of the surface 171 s of the cladding layer 171 due to the gap GP. The gap GP here may be a space filled with air, a specific gas, or in an approximate vacuum state.

。當第一微透鏡ML1的第一曲率半徑R1、第二微透鏡ML2的第二曲率半徑R2以及第一微透鏡ML1和第二微透鏡ML2之間的垂直間距d設計在上述的範圍內時，多道指紋影像光線FPi在間隙GP內是以平行光的方式進行傳遞。因此，間隙GP的間隙厚度（例如垂直間距d）變異並不會影響指紋影像的訊號品質。 In this embodiment, the correspondingly arranged first microlens ML1 and second microlens ML2 are separated by a vertical distance d along the direction Z, and the vertical distance d satisfies the following relationship:

. When the first radius of curvature R1 of the first microlens ML1, the second radius of curvature R2 of the second microlens ML2, and the vertical distance d between the first microlens ML1 and the second microlens ML2 are designed within the above range, The multiple fingerprint image light rays FPi transmit in the form of parallel light in the gap GP. Therefore, the variation of the gap thickness (such as the vertical distance d) of the gap GP will not affect the signal quality of the fingerprint image.

For example, the fingerprint image light FPi entering the photosensitive device 100 at an appropriate angle passes through the hole LSa of the light-shielding pattern layer LS and is refracted by the second microlens ML2 and the first microlens ML1, and then passes through the first collimating structure CM1. The first holes CM1a are transmitted to the corresponding light receiving surfaces 115rs of the first photosensitive element 112 to the third photosensitive element 116 . The light receiving surface 115rs here is defined by, for example, the surface of the second electrode E2 of the first photosensitive element 112 to the third photosensitive element 116 facing the second substrate 102 . In other embodiments, it may also be defined by the surface of the photoelectric conversion layer PCL of the first photosensitive element 112 to the third photosensitive element 116 facing the second substrate 102 .

On the contrary, the fingerprint image light uFPi (or unexpected external ambient light) entering the photosensitive device 100 at a relatively large incident angle will be refracted by the first collimator after passing through the hole LSa of the light-shielding pattern layer LS and being refracted by the second microlens ML2. The straight structure CM1 is blocked and cannot be transmitted to the corresponding first photosensitive element 112 to third photosensitive element 116 . That is to say, the first microlens ML1 and the second microlens ML2 respectively disposed on the two substrates and corresponding to each other can reduce the incident angle of light transmitted to the first photosensitive element 112 to the third photosensitive element 116 . That is to say, the matching design of the first microlens ML1 and the second microlens ML2 can limit the light-receiving range of the photosensitive device 100, and effectively suppress background noise (that is, the sensing signal generated by unexpected light), so as to increase the fingerprint signal Signal-to-noise ratio (SNR). In addition, it can also replace part of the light-shielding pattern layer and the spacer layer (such as a flat layer) therebetween used in general fingerprint sensing modules, which helps to simplify the manufacturing process of the photosensitive device 100 .

On the other hand, since the first microlens ML1 and the second microlens ML2 of the present disclosure are disposed between the first substrate 101 and the second substrate 102, these microlenses can be prevented from being impacted by unexpected external forces in subsequent processes. Damaged by scratches or scratches, it helps to increase the production yield and process margin of the fingerprint sensor module.

In order to make the photosensitive device 100 have an anti-counterfeiting function, a plurality of color filter patterns can also be selectively provided at the part of the holes LSa of the light-shielding pattern layer LS, for example: the first filter element 191, the second filter element 192 and the third filter element. filter element 193, but not limited thereto. In other embodiments, the fingerprint sensing module may not be provided with these color filter patterns.

In particular, since the photosensitive device 100 of the present disclosure has no microlens on the surface facing the display panel 200 , it is suitable to use a direct bond process to connect the display panel 200 and the photosensitive device 100 . In this way, the phenomenon of multiple reflections of light between the display panel 200 and the photosensitive device 100 can be reduced, thereby greatly improving the fingerprint sensing signal of the display device 50 . For example, the photosensitive device 100 and the display panel 200 are bonded together by an optical adhesive layer 220 distributed across the entire surface.

10, 20, 30, 40, 50: display device 100: photosensitive device 101: first substrate 102: second substrate 110: buffer layer 112: first photosensitive element 114: second photosensitive element 115rs: light receiving surface 116: second Three photosensitive elements 120: gate insulating layer 130: interlayer insulating layer 140, 150: planar layer 162, 164, 166: planar layer 171s, 166s, LS1s, CM1s, 250s: surface 171: cladding layer 180: support structure 180h, h1, h2: height 191: first filter element 192: second filter element 193: third filter element 200: display panel 220: optical glue layer 250: cover plate CM1: first collimation structure CM2: second collimation Structure CM3: third collimation structure CM1a: first hole CM2a: second hole CM3a: third hole d: vertical spacing D ₀ , D ₁ , D ₅ , D ₆ : distance DE: drain electrode E1: first electrode E2 : Second electrode FPi, uFPi: Fingerprint image light GE: Gate GP: Gap H ₁ , H ₂ : Height L1, L2, L3: Light ray L ₁ , L ₂ , L ₃ , L ₄ , L ₅ : Length LS: Shading pattern layer LSa: hole ML1: first microlens ML2: second microlens PCL: photoelectric conversion layer PSL: photosensitive element layer R1, R2: radius of curvature S1: first side S2: second side SC: semiconductor pattern SE: Source T: active element X, Y, Z: direction

FIG. 1 is a schematic cross-sectional view of a display device according to an embodiment of the present invention. FIG. 2 is a partially enlarged schematic view of the photosensitive device of FIG. 1 . FIG. 3 is a schematic cross-sectional view of a display device according to an embodiment of the present invention. FIG. 4 is a schematic cross-sectional view of a display device according to an embodiment of the present invention. FIG. 5 is a schematic cross-sectional view of a display device according to an embodiment of the present invention. FIG. 6 is a schematic cross-sectional view of a display device according to an embodiment of the present invention.

10: Display device

100: photosensitive device

101: The first substrate

102: Second substrate

112: The first photosensitive element

114: The second photosensitive element

116: The third photosensitive element

162, 164, 166: flat layers

171: Coating layer

180:Support structure

180h, h1, h2: height

191: the first filter element

192: the second filter element

193: The third filter element

200: display panel

220: optical glue layer

250: cover plate

CM1: first collimation structure

CM2: second collimation structure

CM3: The third collimation structure

CM1a: first hole

CM2a: second hole

CM3a: the third hole

d: vertical spacing

GP: gap

L1, L2, L3: Rays

LS: Light-shielding pattern layer

LSa: hole

ML1: the first microlens

ML2: second microlens

PSL: photosensitive element layer

R1, R2: radius of curvature

S1: first side

S2: second side

X, Y, Z: direction

Claims (18)

A photosensitive device, comprising: a first substrate; a second substrate disposed opposite to the first substrate with a gap between the first substrate and the second substrate; a supporting structure located between the first substrate and the second substrate The gap between the second substrates; a plurality of first microlenses and a plurality of second microlenses are respectively arranged on a first side and a second side of the gap; a first photosensitive element is overlapped on these One of the first microlenses and one of the second microlenses; a second photosensitive element overlapping the other of the second microlenses; and a collimation structure located at the first between the substrate and the first microlenses, wherein the first microlenses are closer to the first photosensitive element than the second microlenses, and between the first microlenses and the second microlenses The vertical distance d is equal to the focal length f1 of the first microlenses plus the focal length f2 of the second microlenses, and the focal length f2 is greater than the focal length f1. The photosensitive device as claimed in claim 1, wherein the second photosensitive element does not overlap the first microlenses. The photosensitive device according to claim 2, further comprising: a third photosensitive element overlapping the other one of the first microlenses and not overlapping the second microlenses. The photosensitive device according to claim 3, further comprising: a first filter element overlapping the first photosensitive element and configured to pass light having a first wavelength; and a second filter element overlapping on the second photosensitive element and configured to pass light having a second wavelength; and a third filter element overlapping the third photosensitive element and configured to pass light having a third wavelength, wherein The first wavelength is greater than the third wavelength, and the third wavelength is greater than the second wavelength. The photosensitive device as claimed in claim 1, wherein the radius of curvature of the second microlenses is greater than the radius of curvature of the first microlenses. The photosensitive device as claimed in claim 5, wherein the material of the first microlenses is the same as that of the second microlenses. The photosensitive device as claimed in claim 1, wherein the refractive index of the first microlenses is greater than the refractive index of the second microlenses under light of the same wavelength. The photosensitive device as claimed in claim 7, wherein the radius of curvature of the first microlenses is equal to the radius of curvature of the second microlenses. The photosensitive device as claimed in claim 1, wherein the vertical distance d between the first microlenses and the second microlenses is less than 1 micron. The photosensitive device according to claim 1, wherein the second photosensitive element overlaps the other one of the first microlenses. A photosensitive device, comprising: a first substrate; A second substrate is arranged opposite to the first substrate, and there is a gap between the first substrate and the second substrate; a plurality of first microlenses and a plurality of second microlenses are respectively arranged in one of the gaps A first side and a second side, wherein the material of the first microlenses is different from the material of the second microlenses and/or the radius of curvature of the first microlenses is different from the curvature of the second microlenses radius; a first photosensitive element overlapping one of the first microlenses; and a second photosensitive element overlapping one of the second microlenses and not overlapping the first microlenses lens. The photosensitive device according to claim 11, wherein the first photosensitive element and the second photosensitive element are located on the first substrate, the first side of the gap is a side of the gap close to the first substrate, and the The second side of the gap is a side of the gap close to the second substrate. The photosensitive device according to claim 11, wherein the first photosensitive element and the second photosensitive element are located on the first substrate, the first side of the gap is a side of the gap close to the second substrate, and the The second side of the gap is a side of the gap close to the first substrate. The photosensitive device as claimed in claim 11, wherein the first photosensitive element overlaps the one of the first microlenses and the other of the second microlenses, and the first microlenses are compared with When the second microlenses are closer to the first photosensitive element, the vertical distance d between the first microlenses and the second microlenses, etc. The focal length f2 of the second microlenses is added to the focal length f1 of the first microlenses, and the focal length f2 is greater than the focal length f1. A photosensitive device, comprising: a first substrate; a second substrate disposed opposite to the first substrate with a gap between the first substrate and the second substrate; a supporting structure located between the first substrate and the second substrate The gap between the second substrates; a plurality of first microlenses and a plurality of second microlenses are respectively arranged on a first side and a second side of the gap; a first photosensitive element is overlapped on these One of the first microlenses and one of the second microlenses; a second photosensitive element overlapping the other of the second microlenses, wherein the second photosensitive element does not overlap the second microlenses some first microlenses; and a collimating structure located between the first substrate and the first microlenses. A photosensitive device, comprising: a first substrate; a second substrate, disposed opposite to the first substrate, and there is a gap between the first substrate and the second substrate; a supporting structure, located between the first substrate and the second substrate The gap between the second substrates; a plurality of first microlenses and a plurality of second microlenses are respectively arranged on a first side and a second side of the gap, wherein the radius of curvature of the second microlenses greater than the radius of curvature of the first microlenses; A first photosensitive element overlapping one of the first microlenses and one of the second microlenses; a second photosensitive element overlapping the other of the second microlenses; and a collimation structure located between the first substrate and the first microlenses. A photosensitive device, comprising: a first substrate; a second substrate disposed opposite to the first substrate with a gap between the first substrate and the second substrate; a supporting structure located between the first substrate and the second substrate The gap between the second substrates; a plurality of first microlenses and a plurality of second microlenses are respectively arranged on a first side and a second side of the gap, wherein under light of the same wavelength, the plurality of The refractive index of the first microlens is greater than the refractive index of the second microlenses; a first photosensitive element overlapping one of the first microlenses and one of the second microlenses; a first microlens Two photosensitive elements overlap the other one of the second microlenses; and a collimation structure is located between the first substrate and the first microlenses. A photosensitive device, comprising: a first substrate; a second substrate disposed opposite to the first substrate with a gap between the first substrate and the second substrate; a supporting structure located between the first substrate and the second substrate The gap between the second substrates; a plurality of first microlenses and a plurality of second microlenses are respectively arranged in one of the gaps The first side and a second side, wherein the vertical distance d between the first microlenses and the second microlenses is less than 1 micron; a first photosensitive element overlaps one of the first microlenses one of the second microlenses; a second photosensitive element overlapping the other of the second microlenses; and a collimation structure located between the first substrate and the first microlenses between lenses.

Images