TW201937208A - Metal-dielectric optical filter, sensor device, and fabrication method - Google Patents

Abstract

An optical filter, a sensor device including the optical filter, and a method of fabricating the optical filter are provided. The optical filter includes one or more dielectric layers and one or more metal layers stacked in alternation. The metal layers are intrinsically protected by the dielectric layers. In particular, the metal layers have tapered edges that are protectively covered by one or more of the dielectric layers.

Description

Metal dielectric optical filter, sensor device and manufacturing method

The present invention relates to a metal dielectric optical filter, a sensor device including the optical filter, and a method of fabricating the optical filter.

Optical sensors are used in optical sensor devices (such as image sensors, ambient light sensors, proximity sensors, hue sensors, and UV sensors) to convert optical signals into electrical signals, thereby Allows detection or image capture of optical signals. An optical sensor typically includes one or more sensor elements and one or more optical filters disposed on the one or more sensor elements.
For example, a color image sensor includes a plurality of color filters disposed in an array (ie, a color filter array (CFA)). CFAs contain different types of color filters with different color passbands, such as red, green, and blue (RGB) filters.
Conventionally, an absorption filter formed using a dye is used as a color filter. Unfortunately, such dye-based color filters have a relatively wide color passband resulting in less shiny colors. Alternatively, a dichroic filter formed by a stacked dielectric layer (ie, an interference filter) can be used as the color filter. These full dielectric color filters have a higher transmission level and a narrower color passband resulting in brighter and more brilliant colors. However, the color passband of a full dielectric color filter experiences a relatively large center wavelength shift accompanied by a change in angle of incidence, resulting in an undesirable color shift.
In addition, full dielectric color filters typically contain a large number of stacked dielectric layers and are relatively thick. Therefore, full dielectric color filters are expensive and difficult to manufacture. In particular, full dielectric color filters are difficult to chemically etch. Therefore, it is preferred to use a lift-off process for patterning. An example of a delamination process for patterning a full-dielectric color filter in a CFA. U.S. Patent No. 5,120,622 to Hanrahan, issued June 9, 1992, and Buchsbaum, issued on January 27, 1998. U.S. Patent No. 6,238, 583 to Edlinger et al., issued May 29, 2001, and U.S. Patent No. 6,638,668, issued to s. U.S. Patent No. 7,648,808 to Buchsbaum et al. However, the stripping process is typically limited to about two times the filter spacing being the height of the filter, making it difficult to achieve a full dielectric CFA for a smaller color image sensor.
In addition to the visible light in the transmitted color passband, both dye-based color filters and full-dielectric color filters also transmit infrared (IR) light, which causes noise. Therefore, a color image sensor typically also includes an IR blocking filter disposed on the CFA. IR blocking filters are also used for other optical sensor devices operating in the visible spectral range. Conventionally, an absorption filter formed of colored glass or a dichroic filter formed of a stacked dielectric layer is used as an IR blocking filter. Alternatively, an induced transmission filter formed of stacked metal and dielectric layers can be used as the IR blocking filter. An example of a metal dielectric IR-blocking filter is disclosed in U.S. Patent No. 5,648,653 issued to Sakamoto et al. reveal.
In order to avoid the use of an IR blocking filter, an induced transmission filter formed of stacked metal and dielectric layers can be used as a color filter. Metal dielectric optical filters, such as metal dielectric color filters, inherently perform IR blocking. Typically, metal dielectric color filters have a relatively narrow color passband that does not significantly shift the wavelength but is accompanied by a change in angle of incidence. In addition, metal dielectric color filters are typically much thinner than full dielectric color filters. An example of a metal dielectric color filter is disclosed in U.S. Patent No. 4,979,803 to McGuckin et al., issued on Dec. 25, 2000, and in U.S. Patent No. 6,031,653, issued on Feb. 29, 2000. U.S. Patent Application Serial No. 2009/0302407, issued to Gidon et al., issued Dec. 10, 2011, to U.S. Patent Application Serial No. 2011/0204463, issued on Aug. 25, 2011, and on April 12, 2012 U.S. Patent Application Serial No. 2012/0085944, the disclosure of which is incorporated herein by reference.
Typically, the metal layer in a metal dielectric optical filter, such as a metal dielectric color filter, is a silver or aluminum layer that is unstable in the environment and is exposed to even small amounts of water or sulfur. Will deteriorate. The chemically etched silver layer exposes the edges of the silver layer to the environment, thereby degrading it. Thus, in most of the examples, the metal dielectric color filter in the CFA is patterned by adjusting only the thickness of the dielectric layer to select different color passbands for the metal dielectric color filter. In other words, different types of metal dielectric color filters having different color pass bands are required to have the same number of silver layers and silver layers of the same thickness as each other. Unfortunately, these requirements severely limit the possible optical design for metal dielectric color filters.
The present invention provides a metal dielectric optical filter that does not have such requirements, and the like is particularly suitable for image sensors and other sensor devices, such as ambient light sensors, proximity sensors, hue sensors, and the like. UV sensor.

Accordingly, the present invention is directed to an optical filter disposed on a substrate, comprising: one or more dielectric layers; and one or more metal layers on the substrate and the one or more The dielectric layers are alternately stacked, wherein each of the one or more metal layers has a tapered edge that extends along a perimeter of one of the metal layers at a periphery of one of the optical filters and along the The entire perimeter of the metal layer is protectively covered by at least one of the one or more dielectric layers.
The invention also relates to a sensor device comprising: one or more sensor elements; and one or more optical filters disposed on the one or more sensor elements, wherein Each of the one or more optical filters includes: one or more dielectric layers; and one or more metal layers alternately stacked with the one or more dielectric layers, wherein the one or more Each of the metal layers has a tapered edge extending along the entire perimeter of one of the metal layers at one of the perimeters of the optical filter and along the entire perimeter of the metal layer by the one or more At least one of the dielectric layers is protectively covered.
The invention further relates to a method of fabricating an optical filter, the method comprising: providing a substrate; applying a photoresist layer to the substrate; patterning the photoresist layer to expose a filter region of the substrate, Forming an overhang in the patterned photoresist layer around the filter region; depositing a multilayer stack onto the patterned photoresist layer and the filter region of the substrate, the multilayer stack including one or more One or more metal layers are alternately stacked; the patterned photoresist layer and a portion of the multilayer stack on the patterned photoresist layer are removed such that a portion of the multilayer stack remaining on the filter region of the substrate is formed An optical filter, wherein each of one or more of the metal layers of the optical filter has a tapered edge extending along a periphery of one of the metal layers at a periphery of one of the optical filters And the entire perimeter is protectively covered by at least one of the one or more dielectric layers along the metal layer.

The invention provides a metal dielectric optical filter with a protected metal layer, which is especially suitable for a sensor device, such as an image sensor, an ambient light sensor, a proximity sensor, a hue A sensor or an ultraviolet (UV) sensor. The optical filter comprises one or more dielectric layers and one or more metal layers alternately stacked. The metal layer is inherently protected by a dielectric layer. In particular, the metal layer has tapered edges that are protectively covered by one or more of the dielectric layers. Accordingly, the metal layer has increased resistance to environmental degradation resulting in an optical filter that is more durable in the environment.
In some embodiments, one or more dielectric layers and one or more metal layers are stacked without any intermediate layers. Referring to FIG. 1A, a first embodiment of an optical filter 100 disposed on a substrate 110 includes three dielectric layers 120 and two metal layers 130 alternately stacked. The metal layers 130 are each disposed between and adjacent to the two dielectric layers 120 and thereby protected from the environment. Dielectric layer 120 and metal layer 130 are continuous layers of any microstructure formed therein.
The metal layer 130 has a tapered edge 131 at one of the perimeters 101 of the optical filter 100. In other words, the thickness of the metal layer 130 is substantially uniform throughout the central portion 102 of the optical filter 100, but is gradually reduced in thickness at the periphery 101 of the optical filter 100. The tapered edge 131 extends along the entire perimeter of the metal layer 130 at the periphery 101 of the optical filter 100. Similarly, the thickness of the dielectric layer 120 is substantially uniform throughout the central portion 102 of the optical filter 100, but is gradually reduced in thickness at the periphery 101 of the optical filter 100. Accordingly, the height of the central portion 102 of the optical filter 100 is substantially uniform, while the periphery 101 of the optical filter 100 is tilted. In other words, the optical filter 100 has a substantially flat top and sloped sides. Typically, the sides of optical filter 100 are inclined from a horizontal plane at an angle of less than about 45 degrees. Preferably, the sides of the optical filter 100 are inclined from a horizontal plane at an angle of less than about 20 degrees, more preferably from a horizontal plane at an angle of less than about 10 degrees.
Advantageously, the tapered edge 131 of the metal layer 130 is not exposed to the environment. In contrast, the tapered edge 131 of the metal layer 130 is protectively covered by one or more of the dielectric layers 120 along the entire perimeter of the metal layer 130. One or more dielectric layers 120 inhibit environmental degradation of the metal layer 130, such as corrosion, by preventing diffusion of sulfur and water into the metal layer 130. Preferably, metal layer 130 is substantially encapsulated by dielectric layer 120. More preferably, the tapered edge 131 of the metal layer 130 is protectively covered by the adjacent dielectric layer 120, and the metal layer 130 is substantially encapsulated by the adjacent dielectric layer 120. In some examples, a top dielectric layer 120 (ie, one of the dielectric layers 120 at the top of the optical filter 100) protectively covers the tapered edges 131 of all of the underlying metal layers 130.
Referring to FIGS. 1B through 1G, a first embodiment of the optical filter 100 can be fabricated by a lift-off process. With particular reference to FIG. 1B, in a first step, substrate 110 is provided. Referring specifically to FIG. 1C, in a second step, a photoresist layer 140 is applied to the substrate 110. Typically, the photoresist layer 140 is applied by spin coating or spray coating.
Referring particularly to FIG. 1D, in a third step, the photoresist layer 140 is patterned to expose a region (ie, a filter region) of the substrate 110 in which the optical filter 100 is to be placed. Other regions of the substrate 110 remain covered by the patterned photoresist layer 140. Generally, the photoresist layer 140 exposes a region of the photoresist layer 140 covering the filter region of the substrate 110 to UV light through a mask first, and then the photoresist layer is formed by using a suitable developer or solvent. The exposed areas of 140 are developed (i.e., etched) to be patterned.
The photoresist layer 140 is patterned in such a manner that an overhang portion 141 (ie, an undercut) is formed in one of the patterned photoresist layers 140 around the filter region. Typically, the overhang 141 is formed by chemically modifying the top portion of one of the photoresist layers 140, such as by using a suitable solvent, such that the top portion is developed to be slower than the bottom portion of one of the photoresist layers 140. Alternatively, the overhang portion 141 may be formed by applying a two-layer photoresist layer 140 (which is composed of one of the lower developed top layers and one of the faster developed ones) to the substrate 100.
The overhang 141 should be large enough to ensure that the subsequent deposition of the coating on the patterned photoresist layer 140 and the substrate 110 (ie, the multilayer stack 103) is discontinuous from the substrate 110 to the patterned photoresist layer 140, as shown in FIG. 1E. Shown in . The overhang 141 is typically greater than 2 μm, preferably greater than 4 μm. In general, the coating should not cover the sides of the patterned photoresist layer 140.
Referring to FIGS. 9A and 9B, when the coating 903 is continuous on the substrate 910 and the patterned photoresist layer 940, the coating 903 is patterned during subsequent stripping of the portion of the photoresist layer 940 and its upper coating 903. The bottom edge of the resist layer 940 is broken to expose the edge of the optical filter formed by the coating 903 (specifically, the edge of the metal layer of the optical filter) to the environment. Unfortunately, for a silver-containing optical filter 900, the exposed edges are susceptible to environmental attack (eg, when exposed to high humidity and high temperatures), causing corrosion, as shown in Figure 9C.
Referring to FIG. 10, in one embodiment of providing a discontinuous coating 1003, the photoresist layer has a two-layer structure and includes a top layer 1042 and a bottom layer 1043. The top layer 1042 is photosensitive and can be patterned by selective exposure to UV light. The bottom layer 1043 is typically non-photosensitive and acts as a release layer. Suitable examples of photoresist include AZ electronic material nLOF 2020 for top photoactive layer 1042 and Microchem Corp. LOR 10 B for bottom release layer 1043.
When the photoresist layer is developed, the extent of the overhang portion 1041 is controlled by the development time. In Figure 10, the development time is selected to provide an overhang 1041 of about 3 μm. Preferably, the bottom release layer 1043 has a thickness greater than about 500 nm and the overhang portion 1041 is greater than about 2 μm. To ensure a clean peel (ie, peeling of the deposited coating 1003 without cracking), the thickness of the coating 1003 should generally be less than about 70% of the thickness of the bottom release layer 1043. In FIG. 10, the thickness of the bottom release layer 1043 is about 800 nm, the thickness of the top photosensitive layer 1042 is about 2 μm, and the thickness of the coating is about 500 nm. The side of the optical filter 1000 below the overhang portion 1041 is inclined at an angle of about 10°.
Referring to Figure 11, in some embodiments, a thicker bottom release layer 1143 is used, and a larger overhang 1141 is used by using a longer development time (e.g., for some processes, about 80 s to about Produced by 100 s). These features improve edge durability by reducing the slope of the sides of the optical filter 1100 and increasing the thickness of the top dielectric layer 1121 at the periphery of the optical filter 1100. In Figure 11, the development time is selected to provide an overhang 1141 of about 6 μm. Preferably, the bottom release layer 1143 has a thickness greater than about 2 μm and the overhang portion 1141 is greater than about 4 μm. The thickness of the coating 1103 should generally be less than about 30% of the thickness of the bottom release layer 1143. In FIG. 11, the thickness of the bottom release layer 1143 is about 2.6 μm, the thickness of the top photosensitive layer 1142 is about 2 μm, and the thickness of the coating 1103 is about 500 nm. The side of the optical filter 1100 below the overhang 1141 is inclined at an angle of about 5°.
With particular reference to FIG. 1E, in a fourth step, a multilayer stack 103 is deposited as a discontinuous coating onto the patterned photoresist layer 140 and the filter regions of the substrate 110. A portion of the multilayer stack 103 disposed on the filter region of the substrate 110 forms the optical filter 100. The layers of the multilayer stack 103 corresponding to the layers of the optical filter 100 can be formed by using various deposition techniques such as: evaporation, such as thermal evaporation, electron beam evaporation, plasma assisted evaporation, or reactive ion evaporation; Plating, such as magnetron sputtering, reactive sputtering, alternating current (AC) sputtering, direct current (DC) sputtering, pulsed DC sputtering or ion beam sputtering; chemical vapor deposition, such as plasma enhanced chemical vapor Deposition; and atomic layer deposition) deposition. In addition, different layers can be deposited by using different deposition techniques. For example, the metal layer 130 can be deposited by sputtering a metal target, and the dielectric layer 120 can be deposited by sputtering a metal target in the presence of oxygen.
Since the overhang portion 141 blocks the periphery of one of the filter regions of the substrate 110, the thickness of the deposited layer gradually decreases toward the periphery 101 of the optical filter 100. The overhang 141 creates a soft roll away from one of the coatings 101 toward the periphery 101 of the optical filter 100. When a dielectric layer 120 is deposited onto a metal layer 130, the dielectric layer 120 covers not only the top surface of the metal layer 130 but also the tapered edge 131 of the metal layer 130, thereby protecting the metal layer 130 from the environment. harm. In addition, the top dielectric layer 120 is typically used as a protective layer for the underlying metal layer 130. For example, in the embodiment of FIG. 11, one of the top dielectric layers 1121 having a thickness of about 100 nm extends over the less durable metal layer (specifically, the tapered edge of the metal layer) and is protectively covered. It is as shown in FIG. 11A.
With particular reference to FIG. 1F, in a fifth step, a portion of the multilayer stack 103 on the patterned photoresist layer 140 is removed (ie, stripped) from the photoresist layer 140. Typically, the photoresist layer 140 is stripped by the use of a suitable release agent or solvent. A portion of the multilayer stack 103 remaining on the filter region of the substrate 110 forms the optical filter 100. Substrate 110 can be, for example, a conventional sensor element.
It should be noted that the stripping process of FIGS. 1B-1F can also be used to simultaneously form a plurality of optical filters 100 of the same type (ie, having the same optical design) on the substrate 110. Additionally, the lift-off process can be repeated to subsequently form one or more optical filters of a different type (ie, having a different optical design) on the same substrate 110. In some embodiments, one or more optical filters that are more durable in the environment can then be formed on the substrate 110 by using a lift-off process or, in some instances, by using a dry or wet etch process. Such that it partially overlaps with one or more optical filters 100 that are less durable in the environment, as will be described in more detail below. Thereby, an optical filter array can be formed on the substrate 110. Substrate 110 can be, for example, a conventional sensor array.
With particular reference to Figure 1G, in an optional sixth step, an additional protective coating 150 is deposited onto the optical filter 100. The protective coating 150 can be deposited by using one of the aforementioned deposition techniques. The protective coating 150 covers both the central portion 102 and the periphery 101 of the optical filter 100 (i.e., all exposed portions of the optical filter 100), thereby protecting the optical filter 100 from the environment.
In other embodiments, the optical filter includes a plurality of corrosion inhibiting layers disposed between the dielectric layer and the metal layer that further protect the metal layer. Referring to FIG. 2, a second embodiment of an optical filter 200 disposed on a substrate 210 is similar to the first embodiment of the optical filter 100, but further includes the insertion of three dielectric layers 220 and two metal layers. Four corrosion inhibiting layers 260 between 230.
The metal layers 230 are each disposed between and adjacent to the two corrosion-inhibiting layers 260, and thereby further protected from the environment. The corrosion-inhibiting layer 260 mainly suppresses corrosion of the metal layer 230 during the deposition process. In particular, the corrosion-inhibiting layer 260 protects portions of the metal layer 230 in the optical path, thereby preventing degradation of the optical properties of the metal layer 230. Preferably, the tapered edge 231 of the metal layer 230 is protectively covered by the adjacent corrosion inhibiting layer 260 and the nearest dielectric layer 220. Therefore, the metal layer 230 is preferably substantially encapsulated by the adjacent corrosion-inhibiting layer 260 and the nearest dielectric layer 220.
A second embodiment of the optical filter 200 can be fabricated by a stripping process similar to the stripping process of one of the first embodiments used to fabricate the optical filter 100. However, the layer of the multilayer stack deposited in the fourth step corresponds to the layer of optical filter 200. In particular, the corrosion-inhibiting layer 260 is deposited before and after each metal layer 230. Advantageously, the corrosion-inhibiting layer 260 inhibits corrosion (ie, oxidation) of the metal layer 230 during deposition of the dielectric layer 220. The corrosion-inhibiting layer 260 is particularly useful when the metal layer 230 contains silver or aluminum. In such embodiments, the corrosion-inhibiting layer 260 inhibits the formation of silver oxide or aluminum oxide between the silver or aluminum from the metal layer 230 and the oxygen from the dielectric layer 220.
The corrosion-inhibiting layer 260 can be deposited as a layer of a metal compound (eg, a metal nitride or metal oxide) by using one of the foregoing deposition techniques (eg, reactive sputtering). Alternatively, the corrosion-inhibiting layer 260 can be formed by first depositing a suitable metal layer by using one of the foregoing deposition techniques and then oxidizing the metal layer. Preferably, the corrosion-inhibiting layers 260 on top of the metal layer 230 are each formed by first depositing a suitable metal layer, oxidizing the metal layer, and then depositing a metal oxide layer. For example, such corrosion inhibiting layer 260 can be formed by sputtering a suitable metal target, followed by oxidation, followed by reactive sputtering of a suitable metal target in the presence of oxygen. Further details of the method of forming a corrosion-inhibiting layer are provided below, and are disclosed in U.S. Patent No. 7,133,197.
The optical filter of the present invention can have a variety of optical designs. The optical design of the exemplary optical filter will be described in more detail later. In general, the optical design of an optical filter is optimized for a particular passband by selecting the appropriate layer number, material, and/or thickness.
The optical filter includes at least one metal layer and at least one dielectric layer. Typically, an optical filter comprises a plurality of metal layers and a plurality of dielectric layers. Typically, the optical filter comprises from 2 to 6 metal layers, 3 to 7 dielectric layers and optionally 4 to 12 corrosion inhibiting layers. In general, increasing the number of metal layers provides a passband with a steeper edge but with a lower in-band transmittance.
The first layer or the bottom layer (i.e., the first layer deposited on the substrate) in the optical design may be a metal layer or a dielectric layer. The last or top layer of the optical design (i.e., the last layer deposited on the substrate) is typically a dielectric layer. When the bottom layer is a metal layer, the optical filter can be in a sequence (M/D) _n The stacked n metal layers (M) and n dielectric layers (D) are composed, wherein n ≥ 1. Alternatively, the optical filter can be in a sequence (C/M/C/D) _n The stacked n metal layers (M) and n dielectric layers (D) and 2n corrosion inhibiting layers (C) are composed, wherein n ≥ 1. When the underlying layer is a dielectric layer, the optical filter can be in a sequence of D (M/D) _n The stack of n metal layers (M) and n + 1 dielectric layers (D), wherein n ≥ 1. Alternatively, the optical filter can be in a sequence of D (C/M/C/D) _n The stacked n metal layers (M), n + 1 dielectric layers (D) and 2n corrosion inhibiting layers (C) are composed, wherein n ≥ 1.
The metal layers are each composed of a metal or an alloy. In some embodiments, the metal layers each consist of silver. Alternatively, the metal layers may each be composed of a silver alloy. For example, a silver alloy consisting essentially of about 0.5 wt% gold and about 0.5 wt% tin provides improved corrosion resistance. In other embodiments, the metal layers are each composed of aluminum. The choice of metal or alloy depends on the application. Silver is generally preferred for optical filters having one passband in the visible region of the spectrum, and aluminum is generally preferred for optical filters having one passband in the UV spectral region, but sometimes in the passband Silver is used when the wavelength is greater than about 350 nm.
The metal layers are usually, but not necessarily, composed of the same metal or alloy, but have different thicknesses. Typically, the metal layers each have a solid thickness between about 5 nm and about 50 nm, preferably between about 10 nm and about 35 nm.
The dielectric layers each consist of a dielectric material that is transparent in the passband of the optical filter.
For optical filters having a passband in the visible region of the spectrum, the dielectric layers typically each consist of a high refractive index dielectric material having a refractive index greater than about 1.65 at 550 nm and transparent in the visible region. Suitable examples of high refractive index dielectric materials for such filters include titanium dioxide (TiO ₂ ), zirconium dioxide (ZrO) ₂ ), cerium oxide (HfO) ₂ ), bismuth pentoxide (Nb) ₂ O ₅ ), bismuth pentoxide (Ta ₂ O ₅ ) and its mixtures. Preferably, the high refractive index dielectric material of such filters also absorbs UV, i.e., absorbs UV in the near UV spectral region. For example, containing TiO ₂ And/or Nb ₂ O ₅ Or a high refractive index dielectric material composed of it can provide enhanced UV blocking, i.e., having a lower out-of-band transmittance in the near UV spectral region. Preferably, the refractive index of the high refractive index dielectric material is greater than about 2.0 at 550 nm, more preferably greater than about 2.35 at 550 nm. A higher refractive index is generally desired. However, currently available transparent high refractive index dielectric materials typically have a refractive index of less than about 2.7 at 550 nm.
For a filter having a pass band in the UV spectral region, the dielectric layers typically each have an intermediate refractive index dielectric material between 300 and 2 nm and a refractive index between 300 and 1.56 or preferably at 300 nm. The refractive index is greater than about 1.65, more preferably greater than about 2.2 at 300 nm and is one of the high refractive index dielectric materials that are transparent in the UV spectral region. Suitable examples of intermediate refractive index and high refractive index dielectric materials for filters having one pass band in the UV spectral region include Ta ₂ O ₅ , cerium oxide (HfO ₂ ), Al2O3 (Al ₂ O ₃ ), cerium oxide (SiO ₂ ), antimony trioxide (ScO) ₃ ), antimony trioxide (Y ₂ O ₃ ), ZrO ₂ , magnesium oxide (MgO ₂ ), magnesium fluoride (MgF ₂ ), other fluorides and mixtures thereof. For example, for a passband centered at a wavelength greater than about 340 nm, Ta ₂ O ₅ Can be used as a high refractive index dielectric material and for passband HfO centered at a wavelength of less than about 400 nm ₂ Can be used as a high refractive index dielectric material.
The dielectric layer typically, but need not be composed of the same dielectric material, but with different thicknesses. Typically, the dielectric layers each have a substantial thickness between about 20 nm and about 300 nm. Preferably, the top dielectric layer has a physical thickness greater than about 40 nm, more preferably greater than about 100 nm, such that the top dielectric layer acts as a protective layer for the underlying metal layer. The physical thickness of each dielectric layer is selected to correspond to one quarter wavelength optical thickness (QWOT) required for an optical design. QWOT is defined as 4 nt, where n is the refractive index of the dielectric material and t is the physical thickness. Typically, the dielectric layers each have a QWOT between about 200 nm and about 2400 nm.
The corrosion inhibiting layers are each composed of a corrosion inhibiting material. Typically, the corrosion inhibiting layer is comprised of a corrosion inhibiting dielectric material. Examples of suitable corrosion inhibiting dielectric materials include tantalum nitride (Si) ₃ N ₄ ), TiO ₂ Nb ₂ O ₅ , zinc oxide (ZnO) and other mixtures thereof. Preferably, the corrosion-inhibiting dielectric material has a compound, such as a nitride or an oxide, having a higher electrical etch potential than one of the metal or alloy of the metal layer.
In some embodiments, the corrosion-inhibiting layer under the metal layer is composed of ZnO, and the corrosion-inhibiting layer above the metal layer comprises a very thin layer composed of zinc (for example, having a thickness of less than 1 nm) and by ZnO One of the thin layers. The zinc layer is deposited on the metal layer and then oxidized to prevent optical absorption. The ZnO layer below and above the metal layer is typically deposited by reactive sputtering. Advantageously, depositing a layer of zinc on the metal layer prior to depositing the ZnO layer prevents the metal layer from being exposed to the activated ionized oxygen species produced during reactive sputtering. The zinc layer preferably absorbs oxygen, thereby inhibiting oxidation of the metal layer.
The corrosion-inhibiting layer is typically suitably thin to substantially avoid affecting the optical design of the optical filter, particularly when it is absorbed in the visible region of the spectrum. Typically, the corrosion-inhibiting layers each have a substantial thickness between about 0.1 nm and about 10 nm, preferably between about 1 nm and about 5 nm. Further details of suitable corrosion inhibiting layers are disclosed in U.S. Patent No. 7,133,197.
The protective coating is usually composed of a dielectric material. The protective coating may be composed of the same dielectric material as the dielectric layer and may have the same thickness range as the dielectric layer. Typically, the protective coating is composed of the same dielectric material as the top dielectric layer and has a thickness that is one of the thicknesses of the design thickness of the top dielectric layer (ie, the thickness required for the optical design). In other words, the top dielectric layer of the optical design is separated between a dielectric layer and a dielectric protective coating. Alternatively, the protective coating may be composed of an organic material such as an epoxy resin.
Referring to FIG. 3, optical filter 300 typically has a filter height h of less than 1 μm, preferably less than 0.6 μm, i.e., a central portion of optical filter 300 is one of the heights from substrate 310. It should be noted that the filter height generally corresponds to the thickness of the previously deposited coating. When used in an image sensor, optical filter 300 typically has a filter width w of less than 2 μm, preferably less than 1 μm, i.e., one of the central portions of optical filter 300. Advantageously, the relatively small filter height allows for a smaller filter spacing when forming a plurality of optical filters 300 by a strip process. Typically, the optical filter 300 in an image sensor has a filter spacing d of less than 2 μm, preferably less than 1 μm, i.e., a spacing between the central portions of the nearest optical filter 300. When used with other sensor devices having larger pixel sizes, the filter width can be from about 50 μm to about 100 μm.
The optical filter is a metal dielectric band pass filter having a high frequency band transmittance and a low band out transmittance, that is, an induced transmission filter. In some embodiments, the optical filter has a relatively narrow color passband color filter in the visible region of the spectrum. For example, the optical filter can be a red, green, blue, cyan, yellow or magenta filter. In other embodiments, the optical filter has a suitable light pass band in the visible region of the spectrum (ie, one of the pass-light luminosity efficiency functions that match the spectral response of the human eye to relatively bright light). A photo-optic filter. In still other embodiments, the optical filter has an IR blocking filter that is one of a relatively wide passband in the visible region of the spectrum.
In such embodiments, the optical filter typically has a maximum in-band transmittance of greater than about 50%, less than about 2% between about 300 nm and about 400 nm (ie, in the near UV spectral region). An average out-of-band transmittance, and an average out-of-band transmittance of less than about 0.3% between about 750 nm and about 1100 nm (i.e., in the infrared (IR) spectral region). In contrast, conventional full dielectric color filters and photopic filters are typically not inherently IR blocked. Typically, in such embodiments, the optical filter also has a low angular offset, i.e., the center angle of the incident angle that varies from 0o. Typically, the optical filter has an angle of incidence of 60o and an amplitude less than about 5% or less than about 30 nm of one of the optical filters centered at 600 nm. In contrast, conventional full dielectric color filters and photopic filters are typically highly angularly sensitive.
The optical design (ie, layer number, material, and thickness) for the exemplary red, green, and blue filters (ie, an exemplary set of RGB filters) is made in Figures 4A, 4B, and 4C, respectively. Into a form. An optical design of one exemplary photopic filter is tabulated in Figure 4D. The layers of each optical design are numbered starting from the first or bottom layer deposited on the substrate.
The metal layers each consist of silver and have a solid thickness between about 13 nm and about 34 nm. The dielectric layers each consist of a high refractive index dielectric material (H) and have a QWOT between about 240 nm and about 2090 nm. For example, a high refractive index dielectric material can be Nb ₂ O ₅ And TiO ₂ The mixture has a refractive index of about 2.43 at 550 nm. The corrosion-inhibiting layers are each composed of ZnO and each have a physical thickness of about 2 nm.
When the high refractive index dielectric material has a refractive index of about 2.43 at 550 nm, the filter height of the red filter is 606 nm, the filter height of the green filter is 531 nm, and the blue filter The filter height is 252 nm and the height of the opacity filter is 522 nm. These filters are much smaller than the filter heights of conventional full dielectric color filters and photopic filters.
Transmission spectra 570, 571, and 572 of exemplary red, green, and blue filters are plotted in Figures 5A and 5B, respectively. The transmission spectrum 570 of the exemplary red filter comprises a red passband centered at about 620 nm, and the transmission spectrum 571 of the exemplary green filter comprises a green passband centered at about 530 nm, and an exemplary blue The transmission spectrum 572 of the color filter includes a blue passband centered at about 445 nm.
Transmission spectra of 573 (0o) and 574 (60o) of an exemplary photopic filter, plotted at an angle of incidence of 0o to 60o, are plotted in Figure 5C. The transmission spectrum 573 of an exemplary photopic filter having an incident angle of 0o comprises a photopic passband centered at about 555 nm. In the transmission spectrum 574 of an exemplary photopic filter at an incident angle of 60o, the opto-light passband is centered at about 520 nm. In other words, the angular shift of an exemplary photopic filter at an incident angle of 60o is about -25 nm. Advantageously, the angular shift of the exemplary photopic filter is much smaller than the angular shift of a conventional full dielectric photopic filter.
Exemplary color filters and photopic filters each have a maximum in-band transmittance of greater than about 60%. Advantageously, exemplary color filters and photopic filters provide improved IR blocking relative to conventional dye-based color filters and full dielectric color filters and photopic filters, thereby providing improved IR blocking, thereby Reduce noise caused by IR leakage. In particular, exemplary color filters and photopic filters have an average out-of-band transmittance of less than about 0.3% each between about 750 nm and about 1100 nm (ie, in the IR spectral region). Exemplary color filters and photopic filters (especially exemplary red filters) also provide improved UV blocking to reduce UV leakage relative to some conventional metal dielectric color filters. The noise caused. In particular, exemplary color filters and photopic filters have an average out-of-band transmittance of less than about 2% each between about 300 nm and about 400 nm (ie, in the near-UV spectral region).
One of the exemplary RGB filter sets, one color gamut 680, and one of the conventional dye-based RGB filter sets, one color gamut 681, are drawn on one of the CIE xy chromaticity diagrams in FIG. 6A for comparison. Advantageously, the color gamut 680 of the exemplary RGB filter set is much larger than the color gamut 681 of the conventional dye-based RGB filter set.
One of the exemplary red filters 682 and one of the incident angles from 0o to 60o, which is plotted on the CIE xy chromaticity diagram in FIG. 6B, is a full-dielectric red filter of 0o to 60o. One color track 683. A color track 684 of one exemplary photopic filter of the incident angle of 0o to 60o is plotted on a CIE xy chromaticity diagram in FIG. 6C. Advantageously, the angular offset of the exemplary red and photopic filters is much smaller than the angular offset of conventional full dielectric red and photopic filters.
In some embodiments, the optical filter has a relatively narrow passband UV filter in the UV spectral region (eg, between about 180 nm and about 420 nm). For example, the optical filter can be an ultraviolet A (UVA) or ultraviolet B (UVB) filter. In such embodiments, the optical filter typically has a maximum in-band transmittance of greater than about 5%, preferably greater than about 15%, and between about 420 nm and about 1100 nm (ie, in visible and IR). In the spectral region, an average out-of-band transmittance of less than about 0.3%. In contrast, conventional full dielectric UV filters are typically not inherently IR blocked. Typically, in such embodiments, the optical filter also has a low angular offset, i.e., the center angle of the incident angle that varies from 0o. Typically, the optical filter has an angle of incidence of 60o and an amplitude less than about 5% or less than about 15 nm of an optical filter centered at 300 nm. In contrast, conventional full dielectric UV filters are generally extremely sensitive.
The optical design of the exemplary UVA, UVB, and 220 nm center filters, ie, layer number, material, and thickness, are summarized in FIG. The metal layers are each composed of aluminum and have a solid thickness between about 10 nm and about 20 nm. The dielectric layers each consist of a high refractive index dielectric material (ie, Ta for UVA filters) ₂ O ₅ And HfO for UVB filters and 220 nm center filters ₂ Composition, and having a physical thickness between about 40 nm and about 60 nm. The exemplary UV filter does not include a corrosion inhibiting layer because the additional protection provided by the corrosion inhibiting layer when the metal layer is composed of aluminum is generally not necessary.
The UVA filter has a filter height of 350 nm, the UVB filter has a filter height of 398 nm, and the 220 nm center filter has a filter height of 277 nm. These filters are much smaller than the filter height of conventional full dielectric UV filters.
The transmission spectra of the exemplary UVA filters plotted at angles of incidence of 0o to 60o are plotted in Figures 13A at 1370 (0o) and 1371 (60o), and in Figure 13B an exemplary UVB filter is plotted at an incident angle of 0o to 60o. Transmission spectra 1372 (0o) and 1373 (60o), and the transmission spectra of exemplary 220 nm center filters at angles of incidence from 0o to 60o are plotted in 1374 (0o) and 1375 (60o). The transmission spectrum 1370 of an exemplary UVA filter having an incident angle of 0o comprises a UVA passband centered at about 355 nm, and the transmission spectrum 1372 of an exemplary UVB filter at an incident angle of 0o comprises The transmission spectrum 1374 of the 220 nm center filter with a 295 nm centering UVB passband and a incident angle of 0o contains a passband centered at approximately 220 nm. The angular offset of an exemplary UV filter at an incident angle of 60o is less than about 15 nm. Advantageously, the angular shift of the exemplary UV filter is much smaller than the angular offset of a conventional full dielectric UV filter.
Exemplary UV filters each have a maximum in-band transmittance of greater than about 10%. In particular, the UVA and UVB filters each have a maximum in-band transmittance of greater than about 20%. Advantageously, the exemplary UV filter provides improved IR blocking relative to conventional full dielectric UV filters, thereby reducing noise caused by IR leakage. In particular, exemplary UV filters each have an average out-of-band transmittance of less than about 0.3% between about 420 nm and about 1100 nm (ie, in the visible and IR spectral regions).
The optical filter of the present invention is particularly useful when included as a component of a sensor device or other active component. The sensor device can be any type of sensor device that includes one or more sensor elements in addition to one or more optical filters in accordance with the present invention. In some instances, the sensor device can also include one or more conventional optical filters. For example, the sensor device can be a combination of an image sensor, an ambient light sensor, a proximity sensor, a hue sensor, a UV sensor, or the like. One or more of the sensor elements can be any type of conventional sensor element. Typically, one or more of the sensor elements are photodetectors, such as photodiodes, charge coupled device (CCD) sensor elements, complementary metal oxide semiconductor (CMOS) sensor elements, germanium detectors, or Dedicated UV sensitive detector. One or more of the sensor elements can be either front-illuminated or back-illuminated. The sensor elements can be any typical sensor material (eg germanium, indium gallium arsenide (IN) _1-x Ga _x As), gallium arsenide (GaAs), germanium, lead sulfide (PbS), or gallium nitride (GaN).
One or more optical filters are disposed on one or more of the sensor elements such that one or more optical filters filter light provided to one or more of the sensor elements. Typically, each optical filter is disposed on a sensor element. In other words, each pixel of the sensor device typically includes an optical filter and a sensor element. Preferably, one or more optical filters are disposed directly on one or more of the sensor elements, such as on one of the one or more sensor elements. For example, one or more optical filters can be formed on one or more of the sensor elements by a stripping process. However, in some embodiments, there may be one or more coatings disposed between one or more optical filters and one or more sensor elements. In some examples, one or more optical filters can be integrated with one or more sensor elements.
In some embodiments, the sensor device includes a single sensor element and a single optical filter disposed on the sensor element in accordance with the present invention. Referring to FIG. 7, a first embodiment of a sensor device 790 includes a sensor element 711 and an optical filter 700 disposed on the sensor element 711. For example, the sensor device 790 can be an ambient light sensor, the sensor element 711 can be a photodiode, and the optical filter 700 can be a photo-optic filter, such as the exemplary embodiment of FIG. 4D. A light-sensitive filter or an IR blocking filter. For another example, the sensor device 790 can be a UV sensor, the sensor element 711 can be a photodiode, and the optical filter 700 can be a UV filter, such as illustrated in FIG. UVA, UVB or 220 nm center filter.
In an exemplary embodiment of an ambient light sensor, a photo-optic filter according to the present invention is integrated with a photodiode. The photopic filter is disposed on the photodiode, usually by, for example, a photodiode ₃ N ₄ One of the components is planarized on the passivation layer. For example, a protective coating or an encapsulating layer may be disposed on the photopic filter and the photodiode. The optical design of the photopic filter is optimized by considering the passivation layer and, when present, the encapsulation layer.
Figure 14 is an optimization of the incident angle of 0o to 60o to integrate with a photodiode. The transmission spectrum of an exemplary photopic filter is 1470 (0o) and 1471 (60o). Light responds to curve 1472. Transmission spectra 1470 and 1471 are associated with a Si ₃ N ₄ The passivation layer and an epoxy encapsulation layer are matched. The transmission spectrum 1470 of an exemplary photopic filter having an incident angle of 0o includes a photopic passband centered at about 555 nm. The transmission spectrum 1470 of the exemplary photopic filter follows the normalized photopic response curve 1472 fairly well at an angle of incidence of 0o to 40o. In addition, the exemplary photopic filter blocks both UR light and IR light at an incident angle of 0o to 60o with a low angular offset. Advantageously, the exemplary photopic filter is also durable in the environment, for example at a temperature of 125 ° C and at a relative humidity of 100% for 96 hours.
In other embodiments, the sensor device includes a plurality of sensor elements and a plurality of optical filters disposed on the plurality of sensor elements in accordance with the present invention. Typically, the sensor elements are arranged in an array. In other words, the sensor elements form an array of sensors, such as a photodiode array, a CCD array, a CMOS array, or any other type of conventional sensor array. Optical filters are also typically placed in an array. In other words, the optical filter forms an optical filter array, such as a color filter array (CFA). Preferably, the sensor array and the optical filter array are corresponding to a two-dimensional array, ie a mosaic. For example, an array can be a rectangular array with columns and rows.
Typically, in such embodiments, the optical filters are substantially separated from one another. In other words, the perimeters of the optical filters are typically not in contact with each other. However, in some instances, the dielectric layers of the optical filter may be inadvertently contacted while the metal layers, particularly the tapered edges, remain separated from one another.
Typically, a plurality of optical filters comprise different types of optical filters having different pass bands from one another. For example, a plurality of optical filters may include color filters (such as red, green, blue, cyan, yellow, and/or magenta filters), photopic filters, IR blocking filters, UV A combination of filters or one of them. In some embodiments, the plurality of optical filters comprise different types of color filters that form a CFA. For example, the plurality of optical filters can include red, green, and blue filters that form an array of RGB filters, such as a Bayer filter array, such as the exemplary red of Figures 4A-4C. , green and blue filters. For another example, the plurality of optical filters can include cyan, magenta, and yellow filters that form a CMY filter array.
Advantageously, different types of optical filters may have a different number of metal layers and/or different thicknesses of metal layers from each other. In some embodiments, at least two of the different types of optical filters comprise a number of different metal layers from each other. In the same or other embodiments, at least two of the different types of optical filters have different metal layer thicknesses from each other. For example, the exemplary blue filter of Figure 4C has a different number of metal layers than the illustrative red and green filters of Figures 4A and 4B. Furthermore, all of the exemplary red, green, and blue filters of FIGS. 4A-4C have different metal layer thicknesses from each other.
Referring to FIG. 8, a second embodiment of a sensor device 890 includes a plurality of sensor elements 811 and a plurality of optical filters 800 and 804 disposed on a plurality of sensor elements 811. The plurality of optical filters 800 and 804 comprise a first type of optical filter 800 having a first pass band and a second type of optical filter having a second pass band different from the first pass band 804. For example, the sensor device 890 can be an image sensor, the plurality of sensor elements 811 can form a CCD array, and the plurality of optical filters 800 and 804 can form a Bayer filter array, wherein only the graphic One part of a column. The first type of optical filter 800 can be a green filter, such as the exemplary green filter of FIG. 4B, and the second type of optical filter 804 can be a red filter (such as FIG. 4A). An exemplary red filter), or a blue filter (such as the exemplary blue filter of Figure 4C).
Any of the embodiments of the sensor device described above may be combined with one or more additional optical filters and one or more additional sensor elements that are more durable in the environment.
Accordingly, in some embodiments, the sensor device includes, in addition to one or more first optical filters disposed on one or more first sensor elements in accordance with the present invention, One or more second optical filters on the plurality of second sensor elements. One or more second optical filters are more durable in the environment than one or more first optical filters. For example, one or more first optical filters may be silver dielectric optical filters in accordance with the present invention, wherein the metal layer is comprised of silver or a silver alloy. One or more second optical filters may be an aluminum dielectric optical filter according to the present invention, wherein the metal layer is composed of aluminum. Alternatively, the one or more second optical filters may be conventional optical filters such as full dielectric, germanium dielectric or hydrogenated germanium dielectric optical filters.
In such embodiments, one or more second optical filters partially overlap one or more first optical filters to provide one or more second optical filter protections that are more durable in the environment The ground covers the perimeter of one or more first optical filters that are less durable in the environment. Advantageously, this cover arrangement provides additional protection against environmental degradation (such as corrosion) of one or more first optical filters, particularly the tapered edges of the metal layer. One or more second optical filters are disposed in one or more first optical filters due to the small slope of the sides of the filter and the small filter height of the one or more first optical filters The slanted sides at the periphery of the illuminator and the substrate are conformed to provide a continuous layer in one or more second optical filters.
The one or more second optical filters preferably extend along the entire periphery of the one or more first optical filters to the inclined sides at the periphery of the one or more first optical filters, including a metal layer cone Shaped edges. Preferably, the one or more second optical filters completely cover the sloped sides at the periphery of the one or more first optical filters. However, one or more second optical filters do not cover or block the one or more first sensor elements.
Typically, the one or more first optical filters and the one or more second optical filters have different pass bands from each other. For example, one or more first optical filters may be color filters (such as red, green, blue, cyan, yellow, or magenta filters), photopic filters, IR blocking filters , or a combination thereof. In particular, the one or more first optical filters may be silver dielectric color filters (such as the exemplary red, green, and/or blue filters of Figures 4A-4C), silver dielectric A light filter (such as the exemplary photopic filter of Figure 4D) or a silver dielectric IR blocking filter.
The one or more second optical filters can be, for example, a combination of a UV filter or a near IR filter or the like. In particular, the one or more second optical filters may be aluminum dielectric UV filters (such as the exemplary UVA, UVB and/or 220 nm center filters of Figure 12) or full dielectric UV filters. Device. Alternatively, one or more of the second optical filters may be a dielectric or hydrogenated ruthenium dielectric near IR filter (such as US Patent Application Publication No. 2014/Hendrix et al., published Jan. 16, 2014). Optical filter as described in 0014838.
Typically, in such embodiments, the sensor device is versatile and combines different functions that are determined primarily by passbands of one or more first optical filters and one or more second optical filters. Different types of optical sensors. One or more first optical filters and one or more first sensor elements form a first type of optical sensor, and one or more second optical filters and one or more second The sensor elements form a second type of optical sensor. For example, the first type of optical sensor may comprise a photometric filter or an IR blocking filter, one of the ambient light sensors, comprising one or more different types of color filters. A sensor, or an image sensor comprising a plurality of different types of color filters. The second type of optical sensor can be, for example, a UV sensor comprising one of the UV filters or a proximity sensor comprising a near IR filter.
Referring to FIG. 15, a third embodiment of a sensor device 1590 includes a first sensor element 1511 and a first optical filter 1500 disposed on the first sensor element 1511 in accordance with the present invention, thereby A first type of optical sensor is formed. The sensor device 1590 further includes a second sensor element 1512 and a second optical filter 1505 disposed on the second sensor element 1512 that is more durable in the environment to form a second type of optical sensation. Detector.
For example, the first type of optical sensor can be an ambient light sensor, and the first optical filter 1500 can be a silver dielectric photopic filter (such as the exemplary photopic filter of FIG. 4D). Or a silver dielectric IR blocking filter. The second type of optical sensor can be, for example, a UV sensor, and the second optical filter 1505 can be an aluminum dielectric UV filter (such as the exemplary UVA, UVB or 220 nm center filter of Figure 12). Light) or a full dielectric UV filter. Alternatively, the second type of optical sensor can be a proximity sensor, and the second optical filter 1505 can be a near IR filter, such as a full dielectric, germanium dielectric or hydrogenated tantalum dielectric. Near IR filter. The first sensor element 1511 and the second sensor element 1512 can be photodiodes.
With particular reference to FIG. 15A, the second optical filter 1505 extends along the entire perimeter of the first optical filter 1500 to the sloped sides of the first optical filter 1500. Thereby, the second optical filter 1505 protectively covers the periphery of the first optical filter 1500, including the tapered edge of the metal layer.
With particular reference to Figures 15B and 15C, the first optical filter 1500 covers and filters the light provided to the first sensor element 1511. The second optical filter 1505 covers and filters the light provided to the second sensor element 1512 and surrounds but does not cover the first sensor element 1511. In the layout illustrated in FIG. 15B, the first sensor element 1511 and the second sensor element 1512 are disposed in a column between the rows of bond pads 1513. In an alternative layout illustrated in FIG. 15C, the second sensor element 1512 is annular and surrounds the first sensor element 1511.
Referring to FIG. 16, a fourth embodiment of a sensor device 1690 includes a plurality of first sensor elements 1611 and a plurality of first optical filters disposed on the plurality of first sensor elements 1611 in accordance with the present invention. The devices 1600, 1604 and 1606 form a first type of optical sensor. The sensor device 1690 further includes a second sensor element 1612 and a second optical filter 1605 disposed on the second sensor element 1612 to form a second type of optical sensor.
For example, the first type of optical sensor can be an image sensor or a hue sensor, and the plurality of first optical filters 1600, 1604, and 1606 can be different types of color filters, such as Exemplary silver dielectric red, green, and blue filters of 4A through 4C. The second type of optical sensor can be, for example, a UV sensor, and the second optical filter 1605 can be a UV filter, such as the exemplary aluminum dielectric UVA, UVB or 220 nm center filter of FIG. Light. Alternatively, the second type of optical sensor can be a proximity sensor, and the second optical filter 1605 can be a near IR filter, such as a full dielectric, germanium dielectric or hydrogenated tantalum dielectric. Near IR filter. The plurality of first sensor elements 1611 and second sensor elements 1612 can form a photodiode array.

100‧‧‧Optical filter

101‧‧‧The perimeter of the optical filter

102‧‧‧The central part of the optical filter

103‧‧‧Multilayer stacking

110‧‧‧Substrate

120‧‧‧ dielectric layer

130‧‧‧metal layer

131‧‧‧Cone edge

140‧‧‧ photoresist layer

141‧‧‧Overhanging

150‧‧‧Protective coating

200‧‧‧Optical filter

210‧‧‧Substrate

220‧‧‧ dielectric layer

230‧‧‧metal layer

231‧‧‧Conical edge

260‧‧‧Corrosion inhibition layer

300‧‧‧Optical filter

310‧‧‧Substrate

Transmission spectrum of 570‧‧‧ red filter

Transmission spectrum of 571‧‧ green filter

Transmission spectrum of 572‧‧‧ blue filter

Transmission spectrum of 573‧‧‧photo-optic filter

Transmission spectrum of 574‧‧ ‧ optical filter

680‧‧‧Color gamut of RGB filter set

681‧‧‧Color gamut of dye-based RGB filter sets

682‧‧‧Red filter color track

683‧‧‧ full dielectric red filter color track

684‧‧‧Color track for optometric filters

700‧‧‧Optical filter

711‧‧‧Sensor components

790‧‧‧Sensor device

800‧‧‧Optical filter

804‧‧‧Optical filter

811‧‧‧Sensor components

890‧‧‧Sensor device

900‧‧‧Optical filter

903‧‧‧Coating

910‧‧‧Substrate

940‧‧‧ photoresist layer

1000‧‧‧Optical filter

1003‧‧‧ discontinuous coating

1041‧‧‧Overhanging

1042‧‧‧Top/Top Photosensitive Layer

1043‧‧‧ bottom/bottom release layer

1100‧‧‧Optical filter

1103‧‧‧ Coating

1121‧‧‧Top dielectric layer

1141‧‧‧Overhanging

1142‧‧‧Top photoactive layer

1143‧‧‧ bottom/bottom release layer

Transmission spectra of 1370‧‧‧UVA filters

Transmission spectra of 1371‧‧‧UVA filters

Transmission spectrum of 1372‧‧‧UVB filter

Transmission spectra of 1373‧‧‧UVB filters

Transmission spectra of 1374‧‧220 nm central filter

Transmission spectra of 1375‧‧220 nm central filter

Transmission spectra of 1470‧‧ ̄ optical filters

Transmission spectra of 1471‧‧ ̄ optical filters

1472‧‧‧光光 response curve

1500‧‧‧First optical filter

1505‧‧‧Second optical filter

1511‧‧‧First sensor component

1512‧‧‧Second sensor component

1513‧‧‧Join pad

1590‧‧‧Sensor device

1600‧‧‧Optical filter

1604‧‧‧Optical filter

1605‧‧‧Second optical filter

1606‧‧‧First optical filter

1611‧‧‧First sensor component

1612‧‧‧Second sensor component

1690‧‧‧Sensor device

d‧‧‧Filter interval

h‧‧‧Filter height

w‧‧‧Filter width

The invention will be described in more detail with reference to the accompanying drawings in which:

1A is a schematic view showing a cross section of a first embodiment of an optical filter;

1B to 1G are schematic views showing steps in a method of manufacturing the optical filter of FIG. 1A;

Figure 2 is a schematic view showing a cross section of a second embodiment of an optical filter;

Figure 3 is a schematic diagram showing one of a cross section of a plurality of optical filters;

4A is a table showing one of the layer numbers, materials, and thicknesses of an exemplary red filter;

Figure 4B is a table showing one of the layer numbers, materials and thicknesses of an exemplary green filter;

Figure 4C is a table showing one of the layer numbers, materials and thicknesses of an exemplary blue filter;

4D is a table showing one of layer number, material and thickness of an exemplary photopic filter;

5A and 5B are diagrams showing transmission spectra of exemplary red, green, and blue filters of FIGS. 4A-4C;

5C is a view showing a transmission spectrum of an incident light angle of 0 to 60° of the exemplary photopic filter of FIG. 4D;

6A is a diagram of an exemplary red, green, and blue (RGB) filter set of FIGS. 4A-4C and a color gamut of a conventional dye-based RGB filter set;

6B is a view of a color track of an exemplary red filter of FIG. 4A and a conventional full dielectric red filter at an incident angle of 0o to 60o;

6C is a view of one of the color spectacles of the exemplary photopic filter of FIG. 4D at an incident angle of 0o to 60o;

Figure 7 is a schematic illustration of a cross section of one of the first embodiments of a sensor device;

Figure 8 is a schematic illustration of a cross section of a second embodiment of a sensor device;

9A and 9B are scanning electron micrographs of a cross section of a continuous coating layer deposited on a patterned photoresist layer and a substrate;

Figure 9C is an optical micrograph of a top view of one of the optical filters formed by the continuous coating of Figures 9A and 9B, showing corrosion after exposure to high humidity and high temperature;

Figure 10 is a scanning electron micrograph of a cross section of one of a discontinuous coating deposited on a patterned photoresist layer and a substrate;

11A and FIG. 11B are scanning electron micrographs of a cross section of a non-continuous coating deposited on a patterned photoresist layer and a substrate, the patterned photoresist layer having a thicker bottom release layer and a larger overhang;

Figure 12 is a table showing one of the layer numbers, materials and thicknesses of exemplary ultraviolet A (UVA), ultraviolet B (UVB) and 220 nm center filters;

Figure 13A is a graph showing the transmission spectrum of an incident angle of 0 to 60o of the exemplary UVA filter of Figure 12;

Figure 13B is a graph showing the transmission spectrum of an incident angle of 0 to 60o of the exemplary UVB filter of Figure 12;

Figure 13C is a graph showing the transmission spectrum of an incident angle of 0o to 60o of the exemplary 220 nm center filter of Figure 12;

Figure 14 is a diagram showing an example of a transmission spectrum of an incident light angle of 0 to 60 o of an exemplary photopicctive filter;

Figure 15A is a schematic illustration of a cross section of a third embodiment of a sensor device;

Figure 15B is a schematic view showing one of the top views of the sensor device of Figure 15A;

Figure 15C is a schematic top view of one of the alternative arrangements of the sensor device of Figure 15A; and

Figure 16 is a schematic illustration of a top view of a fourth embodiment of a sensor device.

Claims (20)

A sensor device comprising: a first sensor element; a first optical filter disposed on the first sensor element; a second sensor element; and a second optical filter disposed on the second sensor element, the second optical filter extending from the first optical in a manner of protectively covering a periphery of one of the first optical filters One of the filters is inclined above the side. The sensor device of claim 1, wherein the second optical filter has a higher environmental tolerance than the first optical filter. The sensor device of claim 1, wherein the second optical filter further extends over a different oblique side of one of the first optical filters. The sensor device of claim 1, Wherein the first sensor element and the first optical filter form a first type of optical sensor, and The second sensor element and the second optical filter form a second type of optical sensor. The sensor device of claim 1, wherein the first sensor element and the first optical filter form an ambient light sensor. The sensor device of claim 1, wherein the first optical filter is a silver-dielectric photopic filter or a silver dielectric infrared (IR) blocking filter. The sensor device of claim 1, wherein the second sensor element and the second optical filter form an ultraviolet (UV) sensor. The sensor device of claim 1, wherein the second optical filter is an aluminum dielectric ultraviolet filter, a 220 nm central filter, or a full dielectric filter. The sensor device of claim 1, wherein the second sensor and the second optical filter form a proximity sensor. The sensor device of claim 1, wherein the second optical filter is a near IR filter. The sensor device of claim 1, wherein the first sensor element and the second sensor element are photodiodes. The sensor device of claim 1, wherein the periphery of the first optical filter comprises a tapered edge of a metal layer. A sensor device including a first sensor element; a first optical filter covering the first sensor element; a second sensor element; and A second optical filter covers the second sensor element and surrounds the first sensor element. The sensor device of claim 13, wherein the second optical filter does not cover the first sensor element. As the sensor device of claim 13, Wherein the first optical filter filters light provided to the first sensor element, and Wherein the second optical filter filters light provided to the second sensor element. The sensor device of claim 13, further comprising: a first column of bonding pads; and A second column of bond pads. The sensor device of claim 16, wherein the first sensor element and the second sensor element are disposed between the first column of bonding pads and the second column of bonding pads. The sensor device of claim 13, wherein the second sensor element is annular. The sensor device of claim 13, wherein the second sensor element surrounds the first sensor element. A sensor device comprising: a plurality of first sensor elements; a plurality of first optical filters, the plurality of first sensor elements and the plurality of first optical filters forming a first type of optical sensor; a second sensor element; and A second optical filter is disposed on the second sensor element, and the second sensor element and the second optical filter form a second type of optical sensor.