Optical interference filter

Abstract

In some implementations, the optical interference filter includes a substrate and one or more layers disposed on the substrate. Each layer comprises: a first layer comprising at least tantalum and oxygen (e.g., tantalum pentoxide (Ta₂O₅)); a second layer comprising at least aluminum and nitrogen (e.g., aluminum nitride (AlN)); and a third layer comprising at least hydrogen and silicon (e.g., silicon hydride (Si:H)). The second layer is disposed between the first and third layers. In some implementations, a first surface of the second layer is disposed on the surface of the first layer, and a second surface of the second layer is disposed on the surface of the third layer.

Description

Background Technology

[0001] Optical devices can be used to capture information related to light. For example, optical devices can capture information related to a set of wavelengths associated with light. Optical devices can include a set of sensor elements (e.g., optical sensors, spectral sensors, and / or image sensors) for capturing information. For example, an array of sensor elements can be used to capture information related to multiple wavelengths. The sensor element array can be associated with a filter. The filter can include a passband associated with a first wavelength range of light transmitted to the sensor element array. The filter can be associated with blocking light of a second wavelength range from reaching the sensor element array. Summary of the Invention

[0002] In some implementations, the optical interference filter includes a substrate; and a plurality of layers disposed on the substrate, wherein each layer comprises: a first layer comprising at least tantalum and oxygen; a second layer comprising at least aluminum and nitrogen; and a third layer comprising at least hydrogen and silicon, wherein the second layer is disposed between the first layer and the third layer.

[0003] In some implementations, the optical interference filter includes one or more layers, each layer comprising: a first layer comprising at least tantalum and oxygen; a second layer comprising at least aluminum and nitrogen; and a third layer comprising at least hydrogen and silicon, wherein the second layer is disposed between the first and third layers.

[0004] In some implementations, the wafer includes a plurality of optical interference filters, wherein each optical interference filter includes: a substrate; and a plurality of layers disposed on the substrate, wherein each layer includes: a first layer comprising at least tantalum and oxygen; a second layer comprising at least aluminum and nitrogen; and a third layer comprising at least hydrogen and silicon, wherein the second layer is disposed between the first layer and the third layer. Attached Figure Description

[0005] Figure 1 This is an overview diagram of the example implementation described in this article.

[0006] Figures 2A-2C This is a diagram of an example optical filter.

[0007] Figure 3 This is an example configuration diagram of the optical filter described in this article.

[0008] Figure 4 This is an example graph showing the extinction coefficient and refractive index of one or more layers of the aluminum nitride (AlN) material described in this article.

[0009] Figure 5 This is an example graph illustrating the transmittance and angular offset performance of the optical filter described herein.

[0010] Figure 6 This is an overview diagram of the example chip. Detailed Implementation

[0011] The following detailed description of the example implementation is with reference to the accompanying drawings. The same reference numerals in different drawings may identify the same or similar elements. The following description uses a spectrometer as an example. However, the techniques, principles, procedures, and methods described herein can be used with any sensor, including but not limited to other optical and spectral sensors.

[0012] Optical filters can be manufactured by forming one or more layers on a substrate. For example, an optical filter may include alternating layers of tantalum pentoxide (Ta2O5) and another material (such as silicon hydride (Si:H)) to allow the optical filter to pass a threshold percentage of light associated with a specific spectral range (e.g., at least 65% of the light) from 800 nanometers (nm) to 1600 nm. Typically, additional layers comprising silicon dioxide (SiO2) are disposed between the alternating layers to bond the alternating layers together.

[0013] However, in some cases, the interface between the first layer comprising Ta2O5 material and the second layer comprising SiO2 material exhibits low durability. For example, multiple optical filters can be diced on a wafer using a dicing process, and due to this process, interface failures occur between the first and second layers in a portion of the multiple optical filters. This results in each optical filter in that portion of the multiple optical filters having dicing defects (e.g., surface areas of that portion of the multiple optical filters are fragmented, delaminated, and / or otherwise damaged), which degrades the performance and / or reliability of each optical filter in that portion of the multiple optical filters. Therefore, additional optical filters are often required to replace those with dicing defects, which consumes manufacturing resources and increases costs. Sometimes, the portion of multiple optical filters with dicing defects constitutes a large portion of the multiple optical filters on the wafer.

[0014] Some implementations described herein provide optical filters comprising one or more layers disposed on a substrate. Each layer may include: a first layer comprising at least tantalum and oxygen (e.g., Ta2O5 material); a second layer comprising at least aluminum and nitrogen (e.g., aluminum nitride (AlN) material); and a third layer comprising at least hydrogen and silicon (e.g., Si:H material). The second layer may be disposed between the first and third layers (e.g., directly between the first and third layers) to bond the first and third layers together. Therefore, the interface between the first and second layers has improved durability compared to the low-durability interface between a layer comprising Ta2O5 material and a layer comprising SiO2 material. Consequently, the interface is less likely to fail during the dicing process used to divide multiple optical filters on a wafer. This reduces the number of optical filters with dicing defects among the multiple optical filters and thus reduces the number of optical filters with degraded performance and / or reliability among the multiple optical filters. This increases the yield of optical filters available for practical purposes among the multiple optical filters. Therefore, there is no need to form additional optical filters, thus saving manufacturing resources and reducing costs. Furthermore, optical filters that do not include single-chip defects have improved durability throughout the operational life of the optical filter compared to optical filters that do not include one or more layers disclosed herein.

[0015] In some implementations, the thickness of the second layer can be less than or equal to a thickness threshold (e.g., less than or equal to 4 nanometers (nm), 6 nanometers, 8 nanometers, 10 nanometers, 15 nanometers, 20 nanometers, 30 nanometers, 40 nanometers, and / or 50 nanometers). In this way, the second layer is a "thin" layer that has minimal impact on filtering performance, transmittance performance, angular offset performance, and / or other properties of optical filters that include one or more layers as described herein.

[0016] Figure 1 This is an overview diagram of example implementation 100 described in this article. (See diagram for example.) Figure 1 As shown, example implementation 100 includes a sensor system 110. Sensor system 110 may be part of an optical system and may provide an electrical output corresponding to sensor determination. Sensor system 110 includes an optical filter structure 120, which includes a filter 130 and an optical sensor 140. For example, optical filter structure 120 may include optical filter 130 performing a passband filtering function. In another example, optical filter 130 may be aligned to an array of sensor elements of optical sensor 140.

[0017] Although some of the implementations described herein can be described in terms of optical filters in a sensor system, the implementations described herein can be used in another type of system, can be used outside the sensor system, or can be used in other configurations.

[0018] like Figure 1 Further illustrated and indicated by reference numeral 150, an input optical signal is directed toward the optical filter structure 120 at one or more incident angles θ. For example, input optical signals 150-1 and 150-2 may be directed toward the optical filter 120 at incident angles θ0 (e.g., configured incident angles) and θ. The input optical signal may include, but is not limited to, light associated with a specific spectral range (e.g., a spectral range centered at approximately 900 nm, such as a spectral range of 800 nm to 1000 nm; a spectral range of 500 nm to 5500 nm; or another spectral range). For example, an optical emitter may direct light toward an optical sensor 140 to allow the optical sensor 140 to perform light measurements. In another example, an optical emitter may direct light of another spectral range for another function, such as a testing function, a sensing function, or a communication function.

[0019] like Figure 1 Further illustrated and indicated by reference numeral 160, a first portion of the optical signal having a first spectral range does not pass through optical filter 130 and optical filter structure 120. For example, a dielectric filter stack of dielectric thin film layers may include a high-refractive-index material layer and a low-refractive-index material layer of optical filter 130, which may cause the first portion of light to be reflected and / or absorbed in a first direction. In this case, the first portion of light may be a threshold portion of light incident on optical filter 130 that is not included in the bandpass of optical filter 130, such as light that is not greater than 95% in a specific spectral range centered at about 900 nm. As indicated by reference numeral 170, a second portion of the optical signal passes through optical filter 130 and optical filter structure 120. For example, optical filter 130 may allow a second portion of light having a second spectral range to pass through in a second direction toward optical sensor 140. In this case, the second portion of light can be the threshold portion of light incident on optical filter 130, within the bandpass of optical filter 130, such as more than 50% of the incident light in the spectral range centered at approximately 900 nanometers. As described in more detail herein, the second portion of light can pass through optical filter 130 with an offset less than the threshold angle.

[0020] like Figure 1The diagram further illustrates that, based on the second portion of the optical signal transmitted to the optical sensor 140, the optical sensor 140 can provide an output electrical signal 180 to the sensor system 110, such as for imaging, ambient light sensing, detecting the presence of an object, performing measurements, or facilitating communication. In some implementations, another arrangement of the optical filter 130 and the optical sensor 140 can be utilized. For example, the optical filter 130 can direct the second portion of the optical signal in a different direction toward the optical sensor 140, which is located at a different position, instead of transmitting the second portion of the optical signal collinearly with the input optical signal.

[0021] As mentioned above, providing Figure 1 As an example. Other examples can be found with... Figure 1 The descriptions differ from those in the text.

[0022] Figures 2A-2C This is a diagram of an example optical filter 200. In some implementations, the optical filter 200 may be an optical interference filter and / or may include at least one of the following: a spectral filter, a multispectral filter, a bandpass filter, a blocking filter, a long-pass filter, a short-pass filter, a dichroic filter, a linearly variable filter, a circularly variable filter, a Fabry-Perot filter, a Bayer filter, a plasma filter, a photonic crystal filter, a nanostructure or metamaterial filter, an absorption filter, a beam splitter, a polarization beam splitter, a notch filter, an anti-reflection filter, a reflector or mirror, etc. Figures 2A-2C A corresponding example stack of optical filter 200 is shown.

[0023] like Figure 2A As shown, the optical filter 200 may include a substrate 205 and one or more layer sets 210 (e.g., one or more optical filter layer sets). The substrate 205 may include a glass substrate, a polymer substrate, a polycarbonate substrate, a metal substrate, a silicon (Si) substrate, a germanium (Ge) substrate, or an active device wafer (e.g., including photodiodes (PDs), PD arrays, avalanche photodiodes (APDs), APD arrays, charge-coupled device (CCD) sensors, and / or complementary metal-oxide-semiconductor (CMOS) sensors, etc.). In some implementations, the thickness of the substrate 205 may be greater than or equal to 20 micrometers (μm), 50 μm, and / or 500 μm. Additionally or alternatively, the thickness of the substrate may be less than or equal to a specific thickness threshold. A specific thickness threshold may, for example, be less than or equal to 5 millimeters (mm).

[0024] Each of one or more layer sets 210 may include a first layer 215, a second layer 220, and a third layer 225. The second layer 220 may be disposed between the first layer 215 and the third layer 225 (e.g., in a stacked manner). In some implementations, the second layer 220 may be disposed on (e.g., directly disposed on) the first layer 215 and the third layer 225. For example, as... Figure 2A As shown, a first surface (e.g., a bottom surface) of the second layer 220 is disposed (e.g., directly disposed) on a surface (e.g., a top surface) of the first layer 215, and a second surface (e.g., a top surface) of the second layer 220 may be disposed (e.g., directly disposed) on a surface (e.g., a bottom surface) of the third layer 225. In some implementations, one or more other layers may be disposed between the first layer 215 and the second layer 220, and / or may be disposed between the second layer 220 and the third layer 225.

[0025] In some implementations, one or more layer sets 210 may be disposed on a single surface (e.g., the top surface) of the substrate 205 (e.g., as shown in the image). Figure 2A (As shown). Alternatively, when the optical filter 200 includes a plurality of layer sets 210 (e.g., two or more layer sets 210), at least one layer set 210 may be disposed on a first surface (e.g., top surface) of the substrate 205, and at least one other layer set 210 may be disposed on a second surface (e.g., bottom surface) of the substrate 205.

[0026] The first layer 215 may include a first material comprising at least tantalum and oxygen. For example, the first material may include tantalum pentoxide (Ta2O5) and, in some implementations, may include one or more other elements or materials (e.g., tantalum, oxygen, hydrogen, silicon, aluminum, nitrogen, silicon dioxide (SiO2) and / or aluminum nitride (AlN)). The third layer 225 may include a third material, which may include at least one other material (e.g., at least one material other than the first material). The third material may include at least one of the following: silicon (Si) materials, silicon and hydrogen (SiH) materials, silicon hydride (Si:H) materials, silicon hydride helium (Si:H-He) materials, silicon hydride nitrogen (Si:HN) materials, amorphous silicon (Si) materials, silicon nitride (SiN) materials, germanium (Ge) materials, germanium hydride (Ge:H) materials, silicon germanium (SiGe) materials, silicon germanium hydride (SiGe:H) materials, silicon carbide (SiC) materials, silicon carbide hydride (SiC:H) materials, niobium pentoxide (Nb₂O₅) materials, niobium titanium oxide (NbTiO�x) materials, and niobium pentoxide tantalum (Nb₂O₅) materials. 2-x Ta xMaterials include O5, titanium dioxide (TiO2), alumina (Al2O3), zirconium oxide (ZrO2), yttrium oxide (Y2O3), or hafnium oxide (HfO2). In some implementations, the third material may include at least hydrogen and silicon. For example, the third material may include SiH, Si:H, Si:H-He, and / or Si:HN materials, and in some implementations, may additionally include one or more other elements and / or materials (e.g., Si, SiN, Ge, Ge:H, SiGe, etc.). Alternatively, in some implementations, the third layer 225 may include the first material (e.g., at least tantalum and oxygen), and the first layer 215 may include the third material (e.g., including at least one other material).

[0027] In some implementations, the second layer 220 may include a second material comprising at least aluminum and nitrogen. For example, the second material may include aluminum nitride (AlN) material and / or one or more other elements or materials (e.g., tantalum, oxygen, hydrogen, helium, silicon, aluminum, nitrogen, alumina (AlO) material, aluminum hydride (AlH) material and / or silicon dioxide (SiO2) material).

[0028] In some implementations, each layer in layer set 210 is associated with a specific thickness. For example, each of the first layer 215, the second layer 220, and the third layer 225 may have a thickness ranging from 5 nanometers to 2000 nanometers (e.g., a thickness greater than or equal to 5 nm and less than or equal to 2000 nm). In some implementations, the second layer 220 (e.g., comprising a second material comprising at least silicon and oxygen) may have a thickness ranging from 2 nanometers to a thickness threshold (e.g., a thickness greater than or equal to 2 nanometers and less than or equal to a thickness threshold). The thickness threshold may be, for example, less than or equal to 4 nm, 6 nm, 8 nm, 10 nm, 15 nm, 20 nm, 30 nm, 40 nm, and / or 50 nm.

[0029] In some implementations, when the optical filter 200 includes multiple layer sets 210 (e.g., two or more layer sets 210), the layers in the first layer set 210 may have the same or different thicknesses as the corresponding layers in the second layer set 210. For example, the first layer 215, the second layer 220, and the third layer 225 in the first layer set may have the same (e.g., equal to, within a threshold that may be less than or equal to 1 nanometer) thickness as the corresponding layers 215, 220, and 225 in the second layer set 210. Alternatively, the first layer 215, the second layer 220, and the third layer 225 in the first layer set may have a different thickness than the first layer 215, the second layer 220, and the third layer 225 in the second layer set 210. Therefore, each of the multiple layer sets 210 may have the same or different thickness profiles as the other layer set 210 of the multiple layer sets 210.

[0030] Therefore, the layer thickness of each layer in layer set 210 and / or the number of one or more layer sets 210 can be selected based on the expected set of optical characteristics of optical filter 200, such as expected passband, expected transmittance, and / or another optical characteristic. For example, the layer thickness of each layer in layer set 210 and / or the number of one or more layer sets 210 can be selected to allow optical filter 200 to be used in a spectral range from 800 nm to 1000 nm (e.g., a center wavelength of approximately 900 nm), a spectral range from 500 nm to 5500 nm, or another spectral range.

[0031] like Figure 2B As shown, optical filter 200 may include a substrate 205 and one or more layers 230 (e.g., one or more optical filter layer sets). Each of the one or more layer sets 230 may include a first layer 215, a second layer 220, and a third layer 225 (e.g., as described elsewhere herein) and may also include a fourth layer 235. The second layer 220 may be disposed between the first layer 215 and the third layer 225, and a particular layer of the first layer 215 and the third layer 225 may be disposed between the second layer 220 and the fourth layer 235 (e.g., in a stacked configuration). In some implementations, the second layer 220 may be disposed (e.g., directly disposed on) the first layer 215 and the third layer 225, and the fourth layer 235 may be disposed (e.g., directly disposed on) a particular layer (e.g., the first layer 215 or the third layer 225). For example, as... Figure 2BAs shown, a first surface (e.g., a bottom surface) of the second layer 220 is disposed (e.g., directly disposed) on a surface (e.g., a top surface) of the first layer 215, a second surface (e.g., a top surface) of the second layer 220 is disposed (e.g., directly disposed) on a first surface (e.g., a bottom surface) of the third layer 225, and a second surface (e.g., a top surface) of the third layer 225 is disposed on a surface (e.g., a bottom surface) of the fourth layer 235. In some implementations, one or more other layers may be disposed between the first layer 215 and the second layer 220, between the second layer 220 and the third layer 225, and / or between a specific layer (e.g., the first layer 215 or the third layer 225) and the fourth layer 235.

[0032] In some implementations, one or more layer sets 230 may be disposed on a single surface (e.g., the top surface) of the substrate 205 (e.g., as shown in the image). Figure 2B (As shown). Alternatively, when the optical filter 200 includes a plurality of layer sets 230 (e.g., two or more layer sets 230), at least one layer set 230 may be disposed on a first surface (e.g., top surface) of the substrate 205, and at least one other layer set 230 may be disposed on a second surface (e.g., bottom surface) of the substrate 205.

[0033] The fourth layer 235 may include a fourth material comprising at least silicon and oxygen, such as SiO2 material and / or one or more other elements or materials (e.g., tantalum, oxygen, aluminum, nitrogen, hydrogen, silicon; silicon oxide (SiO2)). x Materials, where x is less than 2; silicon nitride (SiN) materials; and / or aluminum silicon (AlSi) materials. In some implementations, each layer in layer set 230 is associated with a specific thickness (e.g., in a manner similar to that disclosed herein with respect to each layer of layer set 210). For example, each of the first layer 215, the second layer 220, the third layer 225, and the fourth layer 235 may have a thickness ranging from 5 nanometers to 2000 nanometers (e.g., a thickness greater than or equal to 5 nanometers and less than or equal to 2000 nanometers). In some implementations, the second layer 220 and the fourth layer 235 (e.g., each comprising at least silicon and oxygen) may each have a thickness ranging from 2 nanometers to a thickness threshold (e.g., a thickness greater than or equal to 2 nanometers and less than or equal to a thickness threshold). The thickness threshold may be, for example, less than or equal to 4 nm, 6 nm, 8 nm, 10 nm, 15 nm, 20 nm, 30 nm, 40 nm, and / or 50 nm. The thickness of the second layer 220 can be the same as the thickness of the fourth layer 235 (e.g., equal to, within a threshold that can be less than or equal to 1 nanometer). Alternatively, the thickness of the second layer 220 can be different from the thickness of the fourth layer 235.

[0034] In some implementations, when the optical filter 200 includes multiple layer sets 230 (e.g., two or more layer sets 230), the layers in the first layer set 230 may have the same or different thicknesses as the corresponding layers in the second layer set 230. For example, the first layer 215, the second layer 220, the third layer 225, and the fourth layer 235 in the first layer set may have the same (e.g., equal to, within a threshold that may be less than or equal to 1 nanometer) or different thicknesses as the corresponding thicknesses of the first layer 215, the second layer 220, the third layer 225, and the fourth layer 235 in the second layer set 230. Therefore, the thickness profile of each of the multiple layer sets 230 may be the same or different from the thickness profile of another layer set 230 in the multiple layer sets 230.

[0035] Therefore, the layer thickness of each layer in layer set 230 and / or the number of one or more layer sets 230 can be selected based on the expected set of optical characteristics of optical filter 200, such as expected passband, expected transmittance, and / or another optical characteristic. For example, the layer thickness of each layer in layer set 230 and / or the number of one or more layer sets 230 can be selected to allow optical filter 200 to be used in a spectral range from 800 nm to 1000 nm (e.g., with a center wavelength of about 900 nm), a spectral range from 500 nm to 5500 nm, or other spectral ranges.

[0036] In some implementations, one or more layer sets 210 and / or one or more layer sets 230 can be configured to associate light with a specific spectral range by a threshold percentage. For example, one or more layer sets 210 and / or one or more layer sets 230 can be configured to associate light with a spectral range of 800 nm to 1000 nm (e.g., having a center wavelength of approximately 900 nm) by a threshold percentage. The threshold range can be, for example, greater than or equal to 85%, 90%, 95%, and / or 99%.

[0037] In some implementations, each first layer 215 in one or more layer sets 210 and / or one or more layer sets 230 (e.g., comprising a first material including at least tantalum and oxygen) may have a refractive index in the range of 1.9 to 2.2 for light with wavelengths in the range of 500 nm to 5500 nm. Each second layer 220 in one or more layer sets 210 and / or one or more layer sets 230 (e.g., comprising a second material including at least aluminum and nitrogen) may have a refractive index in the range of 1.9 to 2.2 for light with wavelengths in the range of 500 nm to 5500 nm (and an extinction coefficient less than 0.001). Each third layer 225 in one or more layer sets 210 and / or one or more layer sets 230 (e.g., comprising a third material including at least hydrogen and silicon) may have a refractive index in the range of 3.5 to 3.9 for light with wavelengths in the range of 500 nm to 5500 nm. Each fourth layer 235 (e.g., including a fourth material comprising at least silicon and oxygen) in one or more layer sets 210 and / or one or more layer sets 230 may have a refractive index in the range of 1.3 to 1.5 for light with wavelengths in the range of 500 nm to 5500 nm.

[0038] like Figure 2C As shown, the optical filter 200 may include a substrate 205, one or more layer sets 230 (and / or one or more layer sets 210), Figure 2C (not shown in the image) and another layer set 240 (e.g., another optical filter layer set). The other layer set 240 can be disposed on a specific layer set of one or more layer sets 230 or one or more layer sets 210. For example, as... Figure 2C As shown, other layers 240 can be disposed on the surface of a particular layer 230 (e.g., the bottom surface). Figure 2C As further shown, another layer 240 can be disposed on the surface of the substrate 205.

[0039] Another layer set 240 may include a first other layer 245 and a second other layer 250. The first other layer 245 may include at least hydrogen and silicon, such as SiH materials, Si:H materials, Si:H-He materials, and / or Si:HN materials, and may additionally include one or more other elements and / or materials in some implementations (e.g., in the same or similar manner as the third layer 225). The second layer 250 may include at least silicon and oxygen, such as SiO2 materials, and / or one or more other elements or materials (e.g., in the same or similar manner as the fourth layer 235). Figure 2CAs shown, a second additional layer 250 can be disposed on a first additional layer 245. Therefore, in some implementations, such as when a particular layer set from one or more layer sets 230 or one or more layer sets 210 is disposed on another layer set 240, the surface of the second additional layer 250 of the other layer set 240 can be disposed on the surface of the first layer 215 of the particular layer set. The surface of the first additional layer 245 can be disposed on the surface of the substrate 205.

[0040] In some implementations, each layer of another layer set 240 is associated with a specific thickness (e.g., in a manner similar to that disclosed herein with respect to each layer of layer sets 210 and 230). For example, each of the first other layer 245 and the second other layer 250 may have a thickness in the range of 5 nanometers to 2000 nanometers (e.g., a thickness greater than or equal to 5 nanometers and less than or equal to 2000 nanometers). In some implementations, the second other layer 250 (e.g., comprising at least silicon and oxygen) may have a thickness in the range from 2 nanometers to a thickness threshold (e.g., a thickness greater than or equal to 2 nanometers and less than or equal to a thickness threshold). The thickness threshold may be, for example, less than or equal to 4 nm, 6 nm, 8 nm, 10 nm, 15 nm, 20 nm, 30 nm, 40 nm, and / or 50 nm.

[0041] In some implementations, the optical filter 200 may include a substrate 205, one or more layer sets 210, one or more layer sets 230, and / or another layer set 240. For example, one or more layer sets 210 and / or one or more layer sets 230 may be disposed on the substrate 205 (e.g., on the top and / or bottom surfaces of the substrate 205). One or more layer sets 210 and / or one or more layer sets 230 may be disposed on another layer set 240, which may be disposed on the substrate 205. In some implementations, one or more layer sets 210 and one or more layer sets 230 may be disposed on another layer set 240 and / or the substrate 205 in a specific order (such as an alternating order). One or more layer sets 210 and one or more layer sets 230 may be disposed on the substrate 205 in a specific order to allow one or more layer sets 210 and one or more layer sets 230 to pass light with a threshold percentage associated with a specific spectral range and / or exhibit other properties discussed herein.

[0042] In some implementations, one or more additional layers may be included in the optical filter 200, such as one or more protective layers, one or more capping layers (e.g., providing environmental protection to one or more layer sets 210 and one or more layer sets 230), and / or one or more layers for providing one or more other filtering functions (e.g., blocking agents or anti-reflective coatings, etc.). For example, in a single-surface configuration, additional layers (e.g., capping layers), such as dielectric layers (e.g., including oxide materials such as silicon dioxide (SiO2), zirconium dioxide (ZrO2), and / or yttrium oxide (Y2O3); nitride materials such as silicon nitride (Si3N4), titanium nitride (TiN), and / or zirconium nitride (ZrN); and / or another material providing environmental protection), may be disposed on the surfaces (e.g., the top surface) of one or more layer sets 210 and one or more layer sets 230.

[0043] As mentioned above, Figures 2A-2C Provided as an example. Other examples may be provided. Figures 2A-2C The descriptions differ from those in the text.

[0044] Figure 3 Figure 300 shows an example configuration of the optical filter 200 described herein. The optical filter 200 may include a substrate (e.g., as described herein with respect to...) Figures 2A-2C One or more layers 310 on a substrate 205 that is the same as or similar to the substrate described herein (e.g., as described herein regarding...). Figures 2A-2C One or more layer sets 210 described are the same or similar), one or more layer sets 320 (e.g., those described in this paper regarding...) Figures 2A-2C One or more layer sets 230 described are the same as or similar to those described herein) and / or one or more layer sets 330 (e.g., those described herein regarding Figures 2A-2C The description includes one or more other layer sets 240 that are the same or similar. Figure 3 As shown, layer set 310 includes a first layer of Ta2O5 material, a second layer of AlN material, and a third layer of Si:H material, wherein the second layer is disposed between the first and second layers. Layer set 320 includes a first layer of Ta2O5 material, a second layer of AlN material, a third layer of Si:H material, and a fourth layer of SiO2 material, wherein the second layer is disposed between the first and second layers, and the third layer is disposed between the second and fourth layers. Layer set 330 includes a first layer of Si:H material and a second layer of SiO2 material. Figure 3As further shown, one or more layer sets 310, one or more layer sets 320 and / or one or more layer sets 330 may be arranged on the substrate in a specific order (e.g., to allow the optical filter 200 to pass through light with a threshold percentage associated with a specific spectral range and / or exhibit other properties discussed elsewhere herein).

[0045] As mentioned above, providing Figure 3 As an example. Other examples can be found with... Figure 3 The descriptions differ from those in the text.

[0046] Figure 4 This is an example graph 400 showing the extinction coefficient (k) and refractive index (n) of one or more layers comprising at least aluminum and nitrogen (e.g., AlN materials) as described in this paper. Figure 4 As shown, for light with wavelengths in the range of 500 nm to 2000 nm, the extinction coefficient can be less than 0.001. Figure 4 As further shown, for light with wavelengths in the range of 500 nm to 2000 nm, the refractive index can be less than 2.2.

[0047] As mentioned above, providing Figure 4 As an example. Other examples can be found with... Figure 4 The descriptions differ from those in the text.

[0048] Figure 5 Example graph 500 shows the transmittance and angular offset performance of the optical filter 200 described herein. Figure 5 As shown and indicated by reference numeral 510, when the light has an incident angle of 0 degrees, the optical filter 200 can transmit light with wavelengths greater than approximately 85% (peak approximately 97%) in the range of 935 nm to 960 nm. Figure 5 As further shown and indicated by reference numeral 520, when light has an incident angle of 30 degrees, optical filter 200 can transmit greater than about 85% (peak about 96%) of light in the wavelength range from 928 nm to 954 nm. In some implementations, for incident angles ranging from 0 degrees to 30 degrees, the angular offset at the center wavelength of optical filter 200 can be less than 1.0% of the center wavelength. For example, when the optical filter is configured for a center wavelength of 940 nanometers (nm), the optical filter can have an angular offset of, for example, less than 9.4 nm at incident angles up to 30 degrees.

[0049] In some implementations, the optical filter 200 can achieve a transmittance at the center wavelength that is greater than a transmittance threshold, such as greater than 80%, greater than 85%, greater than 90%, and / or greater than 95% (e.g., the peak transmittance of the optical filter at an incident angle ranging from 0 degrees to 30 degrees). Furthermore, the optical filter 200 can achieve ripple of less than + / -10%, less than + / -5%, or less than + / -1%, where ripple represents the deviation of transmittance across the passband at an incident angle ranging from 0 degrees to 30 degrees.

[0050] As mentioned above, providing Figure 5 As an example. Other examples can be found with... Figure 5 The descriptions differ from those in the text.

[0051] Figure 6 This is an overview diagram of the example chip 600. (As shown...) Figure 6 As shown, the wafer may include multiple optical filters 200. The multiple optical filters 200 can be formed on the wafer 600 using sputtering processes such as magnetron sputtering, dicing processes (such as dicing), and / or other processes. In some implementations, a threshold percentage of the multiple optical filters 200 excludes dicing defects. For example, the threshold percentage may be greater than or equal to 50%, 65%, 75%, 85%, 95%, and / or 99%.

[0052] Optical filter 200 may include a dicing defect when a region on the surface (e.g., the top surface) of the optical filter 200 is fragmented, delaminated, and / or otherwise damaged (e.g., due to sputtering and / or dicing processes), and this region is greater than or equal to a threshold size. The threshold size may, for example, be greater than or equal to 0.001%, 0.00125%, 0.0025%, 0.0050%, 0.01%, 0.05%, 0.1%, and / or 0.5% of the surface area of ​​the optical filter 200. In some implementations, the threshold size may be greater than or equal to 10 square micrometers (μm). 2 ), 20μm 2 30μm 2 40μm 2 and / or 50μm 2 Therefore, multiple optical filters 200 of the threshold percentage may exclude damaged areas that are greater than or equal to the threshold size.

[0053] The wafer 600 may include a plurality of optical filters 200 whose durability is improved without including a threshold percentage of single-piece defects, because each of the plurality of optical filters 200 includes one or more layer sets 210 and / or one or more layer sets 230 as described herein.

[0054] As mentioned above, providing Figure 6 As an example. Other examples may differ from those regarding... Figure 6 The description.

[0055] The foregoing disclosure provides explanations and descriptions, but is not intended to be exhaustive or to limit the implementation to the precise form disclosed. Modifications and variations can be made based on the foregoing disclosure or derived from practice of the implementation.

[0056] As used in this article, the threshold can refer to greater than the threshold, greater than or equal to the threshold, less than the threshold, less than or equal to the threshold, equal to the threshold, not equal to the threshold, etc., depending on the context.

[0057] Although specific combinations of features are recited in the claims and / or disclosed in the specification, these combinations are not intended to limit the disclosure of the various implementations. In fact, many of these features can be combined in ways not expressly mentioned in the claims and / or not disclosed in the specification. While each dependent claim listed below may be directly dependent on only one claim, the disclosure of the various implementations includes every dependent claim combined with all other claims in the claim set. As used herein, the phrase “at least one” in the list of references refers to any combination of these items, including a single member. For example, “at least one of a, b, or c” is intended to cover a, b, c, ab, ac, bc, and abc, as well as any combination having multiple identical items.

[0058] Unless explicitly stated otherwise, no element, action, or instruction used herein should be construed as critical or necessary. Similarly, as used herein, the articles “a” and “one” are intended to include one or more items and may be used interchangeably with “one or more.” Furthermore, as used herein, the article “described” is intended to include one or more items referenced in conjunction with the article “the” and may be used interchangeably with “one or more.” Additionally, as used herein, the term “set” is intended to include one or more items (e.g., related items, unrelated items, or a combination of related and unrelated items) and may be used interchangeably with “one or more.” Where only one item is intended to be included, the phrase “only one” or similar wording is used. Furthermore, as used herein, the terms “has / have / having” are intended to be open-ended terms. Furthermore, unless explicitly stated otherwise, the phrase “based on” is intended to mean “at least partially based on.” Likewise, unless explicitly stated otherwise (e.g., if used in conjunction with “or” or “only one of them”), as used herein, the term “or” is intended to be inclusive when used in a series and may be used interchangeably with “and / or.” Furthermore, for ease of description, spatial relative terms, such as “below,” “lower,” “bottom,” “above,” “upper,” “top,” etc., may be used herein to describe the relationship of one element or feature to another element(s)(s) shown in the accompanying drawings. Spatial relative terms are intended to include different orientations of the apparatus, equipment, and / or elements in use or operation, other than those described in the figures. Apparatus may be oriented in other ways (rotated 90 degrees or in other orientations), and the spatial relative descriptors used herein may be interpreted accordingly.

[0059] As used herein, the term "material X," where X is a chemical composition such as AlN, SiO2, or Si:H, indicates that the material X comprises at least a threshold percentage of X. For example, the threshold percentage may be greater than or equal to 1%, 5%, 10%, 25%, 50%, 75%, 85%, 90%, 95%, and / or 99%. Similarly, when a material is referred to by a specific chemical name or formula, the material may include non-stoichiometric variations of the stoichiometric exact chemical formula identified by the chemical name. For example, the aluminum nitride (AlN) material described herein may include AlN... x , where x is in the range from 0.8 to 1.2.

Claims

1. An optical interference filter, comprising: a substrate; a first set of layers disposed on the substrate, wherein the first set of layers includes: a first layer disposed on the substrate, the first layer including at least hydrogen and silicon, and a second layer disposed on the first layer, the second layer including at least silicon and oxygen, and a plurality of second sets of layers disposed on the first set of layers, wherein the first set of layers is between the substrate and the plurality of second sets of layers, and wherein each second set of layers of the plurality of second sets of layers includes: a third layer including at least tantalum and oxygen; a fourth layer including at least aluminum and nitrogen; and a fifth layer including at least hydrogen and silicon, wherein: the fourth layer is disposed between the third layer and the fifth layer.

2. The optical interference filter of claim 1, wherein: the third layer includes a tantalum pentoxide (Ta2O5) material; the fourth layer includes an aluminum nitride (AIN) material; and the fifth layer includes a hydrogenated silicon (Si:H) material.

3. The optical interference filter of claim 1, wherein a thickness of the fourth layer is in a range from 2 nanometers to 10 nanometers.

4. The optical interference filter of claim 1, wherein a first surface of the fourth layer is disposed on a surface of the third layer, and wherein a second surface of the fourth layer is disposed on a surface of the fifth layer.

5. The optical interference filter of claim 1, wherein each second set of layers further includes a sixth layer including at least silicon and oxygen, and wherein one of the third layer or the fifth layer is disposed between the fourth layer and the sixth layer.

6. The optical interference filter of claim 5, wherein the sixth layer includes a silicon dioxide (SiO2) material.

7. The optical interference filter of claim 1, wherein a thickness of the substrate is greater than or equal to 50 micrometers.

8. The optical interference filter of claim 1, wherein the plurality of second sets of layers are configured to pass a threshold percentage of light associated with a spectral range from 800 nanometers to 1000 nanometers, wherein the threshold percentage of light is greater than or equal to 85%.

9. The optical interference filter of claim 1, wherein the first set of layers is disposed on a first surface of the substrate, and at least one other set of layers is disposed on a second surface of the substrate.

10. An optical interference filter, comprising: one or more first sets of layers, wherein each first set of layers includes: a first layer including at least tantalum and oxygen; a second layer including at least aluminum and nitrogen; and a third layer including at least hydrogen and silicon, wherein: the second layer is disposed between the first layer and the third layer; a second set of layers including: a fourth layer including at least hydrogen and silicon, and a fifth layer disposed on the fourth layer, the fifth layer including at least silicon and oxygen; and a substrate, wherein the second set of layers is between the substrate and the one or more first sets of layers, wherein the fourth layer is disposed on the substrate.

11. The optical interference filter of claim 10, wherein a thickness of the second layer is in a range from 2 nanometers to 40 nanometers.

12. The optical interference filter of claim 10, wherein a first surface of the second layer is disposed on a surface of the first layer, and wherein a second surface of the second layer is disposed on a surface of the third layer.

13. The optical interference filter of claim 10, wherein a surface of the fifth layer is disposed on a surface of the first layer.

14. A wafer comprising: a plurality of optical interference filters, wherein each optical interference filter comprises: a substrate; a first set of layers disposed on the substrate, wherein the first set of layers comprises: a first layer disposed on the substrate, the first layer comprising at least hydrogen and silicon, and a second layer disposed on the first layer, the second layer comprising at least silicon and oxygen, and a plurality of second sets of layers disposed on the first set of layers, wherein the first set of layers is between the substrate and the plurality of second sets of layers, and wherein each second set of layers of the plurality of second sets of layers comprises: a third layer comprising at least tantalum and oxygen; a fourth layer comprising at least aluminum and nitrogen; and a fifth layer comprising at least hydrogen and silicon, wherein: the fourth layer is disposed between the third layer and the fifth layer.

15. The wafer of claim 14, wherein a thickness of the fourth layer is in a range from 2 nanometers to 40 nanometers.

16. The wafer of claim 14, wherein a first surface of the fourth layer is disposed on a surface of the third layer, and wherein a second surface of the fourth layer is disposed on a surface of the fifth layer.

17. The wafer of claim 14, wherein each second set of layers further comprises a sixth layer comprising at least silicon and oxygen, and wherein one of the third layer or the fifth layer is disposed between the fourth layer and the sixth layer.

18. The wafer of claim 17, wherein the sixth layer comprises silicon dioxide (SiO2) material.

19. The wafer of claim 14, wherein the plurality of optical interference filters are formed using a singulation process, wherein greater than or equal to 95% of the plurality of optical interference filters do not include a singulation defect.

20. The wafer of claim 14, wherein: the third layer comprises tantalum pentoxide (Ta2O5) material; the fourth layer comprises aluminum nitride (AIN) material; and the fifth layer comprises hydrogenated silicon (Si:H) material.

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