Component arrangement, package and package arrangement as well as methods for manufacturing

Abstract

Component arrangement, - a carrier substrate; - a spacer which is arranged on the support substrate surrounding a construction space and has an outlet opening on a side facing away from the support substrate; - an optical component which is arranged in the installation space; - a contact connection that electrically connects the optical component to external contacts located outside the installation space; - a covering substrate which is arranged on the spacer and with which the exit opening is covered in a translucent manner; and - a light-reflecting surface formed on an anisotropically etched silicon component and arranged in the build space as an inclined surface at an angle of approximately 45° to the surface of the substrate facing the build space, such that light incident on the light-reflecting surface in a horizontal direction can be emitted in a vertical direction through the opening and the top substrate and vice versa; wherein the optical component is arranged in the build space within an upper opening of the anisotropically etched silicon component, which in plan view has an incomplete trapezoidal shape that is limited in one direction of its extent.

Description

[0001] The invention relates to a component arrangement, a package and a package arrangement as well as methods for manufacturing. background

[0002] In connection with component arrangements, it is known to arrange components or elements, for example, optical components that emit or absorb light, in a housing. The component arrangement can be used to produce a package.

[0003] A method for producing such a component arrangement is known, for example, from document WO 2011 / 035 783 A1. A spacer is arranged on a carrier substrate such that the spacer surrounds a construction space in which a component is arranged. The construction space is sealed by placing a cover substrate on the spacer. The cover substrate can provide a translucent exit opening through which light can be emitted or received. Wall surfaces of the spacer facing the construction space can be provided with a metallization to provide a light-reflecting mirror coating.

[0004] Document WO 2016 / 055520 A1 describes the production of a package for a laser component with a housing comprising a carrier having a cavity with a bottom surface and a side wall. The cavity widens from the bottom surface. A laser chip is arranged in the cavity at the bottom surface, the emission direction of which is oriented parallel to the bottom surface. Also arranged in the cavity is a reflective element that rests against an edge between the bottom surface and the side wall. A reflective surface of the reflective element forms an angle of 45 degrees with the bottom surface of the cavity. The emission direction also forms an angle of 45 degrees with the reflective surface of the reflective element.

[0005] Component arrangement is also known from document WO 2017 / 149 573 A1.

[0006] In document US 7 177 331 B2, a laser diode is installed in a so-called TO housing.

[0007] Document US 8,471,289 B2 discloses a semiconductor laser unit comprising a Si(100) substrate in which a recess with an opening and a bottom surface surrounded by inner wall surfaces is formed, a semiconductor laser element disposed on the bottom surface, and a transparent sealing glass mounted on top of the Si(100) substrate to seal the opening. The laser light emitted by the semiconductor laser element is reflected by a metallic reflective film formed on an inner wall surface and then transmits through the sealing glass to be emitted externally.

[0008] Document JP 2006 147 751 A describes an optical semiconductor device. A semiconductor laser element is provided on the bottom surface of a package with an opening by means of a submount. The laser element is arranged such that its laser light-emitting end face can be perpendicular to the bottom surface of the package. Since the opening of the package is covered with a transparent substrate, the opening is tightly sealed. Furthermore, a mirror is attached to the main surface of the transparent substrate. Since the reflecting surface of the mirror is arranged facing the laser light-emitting end face of the semiconductor laser element, the surface reflects the laser light emitted by the semiconductor laser element toward the transparent substrate side.

[0009] An optoelectronic component is disclosed in document US 2017 / 0 148 959 A1. The optoelectronic component comprises a housing, on the top of which a cavity is formed, which is delimited by a wall. The housing has a void and a surface. The wall is arranged between the cavity and the void. The void is arranged between the surface of the housing and the wall. The wall and the surface are arranged at least partially parallel to each other. The wall comprises an optically transparent material and has a wall thickness of 1 µm to 100 µm. Summary

[0010] The object of the invention is to provide a component arrangement, a package and a package arrangement and method for manufacturing, with which an improved light guidance or deflection of light rays in a construction space with an optical component is provided.

[0011] To achieve this, a component arrangement, a package, and a package arrangement according to independent claims 1, 11, and 13 are provided. Furthermore, methods for producing a component arrangement, a package, and a package arrangement according to independent claims 10, 14, and 15 are provided.

[0012] According to one aspect, a component arrangement is provided which comprises the following: a carrier substrate, a spacer which is arranged on the carrier substrate surrounding a construction space and has an exit opening on a side facing away from the carrier substrate; an optical component which is arranged in the construction space; a contact connection which electrically connects the optical component to external contacts which are arranged outside the construction space; a cover substrate which is arranged on the spacer and with which the exit opening is covered in a light-permeable manner;and a light-reflecting surface formed on an anisotropically etched silicon component and arranged in the build space as an inclined surface at an angle of approximately 45 degrees to the surface of the carrier substrate facing the build space, such that light irradiated in the horizontal direction onto the light-reflecting surface can be radiated in the vertical direction through the opening and the cover substrate and vice versa;

[0013] According to further aspects, a package with a component arrangement and a housing in which the component arrangement is accommodated, as well as a package arrangement are created which has a planar arrangement of several packages.

[0014] A further aspect relates to a method for producing a component arrangement comprising the following steps: producing an anisotropically etched silicon component from a silicon single crystal by means of anisotropic etching, wherein the silicon single crystal is tilted by approximately 9.7 degrees to the 100 crystal orientation such that a 111 crystal plane with a slope of approximately 45 degrees is formed; and producing a component arrangement using the anisotropically etched silicon component, wherein a light-reflecting surface is formed in the component arrangement with the 111 crystal plane with the slope of approximately 45 degrees.

[0015] According to additional aspects, a method for producing a package and a method for producing a package arrangement are provided, wherein the package / package arrangement is produced in the panel, for example by means of wafer level packaging.

[0016] The proposed technology makes it possible to redirect horizontal light rays into the horizontal direction at the approximately 45-degree inclined light-reflecting surface within the assembly space provided in the component arrangement, and vice versa. Light emitted by the optical component can thus be redirected from the horizontal direction to the vertical direction in order to emit the light rays through the exit opening. Conversely, light incident in the vertical direction through the exit opening can be redirected into the horizontal direction at the light-reflecting surface. The light-reflecting surface is provided with the anisotropically etched silicon component as the surface of this silicon component.

[0017] The optical component can be designed as a light-emitting or light-absorbing component, for example as a light-emitting diode or light-absorbing photodiode, for example an avalanche photodiode or laser diode.

[0018] The light-emitting component can be designed to emit light beams in a directed and bundled form, for example in the form of essentially directed laser radiation with central emission of the intensity maximum with optional beam divergence (beam expansion).

[0019] The proposed technology allows the optical component to be arranged in the installation space such that the emitted light rays exit or the received light rays enter in a vertical direction. In contrast to the prior art, in order to emit light rays in a vertical direction (relative to the surface of the carrier substrate), it is not necessary to arrange the optical component upright in the installation space, as is provided for in the prior art (see, for example, US Pat. No. 7,177,331 B2). Using the proposed technology, the overall height of the component arrangement can be reduced and assembly simplified.

[0020] The contact connection may comprise a through-plating through the carrier substrate, wherein the external contacts may be arranged on the underside of the carrier substrate.

[0021] A contact connection extending laterally out of the installation space can be provided, for example, on the surface of the carrier substrate facing the installation space, in particular such that the laterally extending contact connection is formed between the carrier substrate and the spacer. The contact connection can comprise a plurality of individual contact connections.

[0022] A support surface of the anisotropically etched silicon component can run essentially parallel to the surface of the carrier substrate facing the build space. In this embodiment, the light-reflecting surface is inclined at an angle of approximately 45 degrees to the support surface.

[0023] The anisotropically etched silicon component can be arranged in the installation space surrounded by the spacer. The anisotropically etched silicon component, on which the light-reflecting surface is provided, can be arranged in the installation space separately and spaced from the spacer, in particular such that there is no physical contact between the anisotropically etched silicon component and the spacer surrounding the installation space.

[0024] The spacer can be at least partially formed with the anisotropically etched silicon component. In this alternative embodiment, the anisotropically etched component forms the spacer partially or completely. In one embodiment, it can be provided that the spacer surrounding the installation space is formed completely from the anisotropically etched silicon component all the way around the installation space, for example as a one-piece anisotropically etched silicon component. In the various embodiments, an inner wall surface of the spacer facing the installation space has an inclination of approximately 45 degrees, at least in the region of the light-reflecting surface. In this or other embodiments, the spacer can be formed as a one-piece frame that surrounds the installation space all the way around.

[0025] A first wall surface of the spacer, which faces the installation space and is arranged outside a region with the light-reflecting surface, can be inclined to the vertical direction at a first angle different from 45 degrees. While the wall surface of the spacer facing the installation space has an inclination of approximately 45 degrees in the region of the light-reflecting surface, the first wall surface outside the region with the light-reflecting surface is inclined at a different angle, for example, approximately 64.5 degrees. The first wall surface of the spacer can be arranged opposite the light-reflecting surface.

[0026] A second wall surface of the spacer, different from the first, facing the installation space and arranged outside the region with the light-reflecting surface, can be inclined to the vertical direction at a second angle different from 45 degrees, which is different from the first angle. The first / or the second wall surface, which have an angle of inclination different from 45 degrees, can be arranged in a section of the spacer formed by the anisotropically etched silicon component or outside such a section. The second angle can be approximately 55.3 degrees, for example. The second wall surface can be arranged in a section of the spacer that borders the light-reflecting surface and / or the first wall surface. Opposite wall surfaces can be formed with the second angle of inclination.Alternatively, wall surfaces other than 45 degrees can also be designed with other angles.

[0027] The spacer can be formed by means of the anisotropically etched silicon component as a single-piece or multi-piece frame that completely surrounds the installation space. When viewed from above, the frame has a trapezoidal shape. The opening angles (in corner regions) on the side with the 45-degree mirror plane can each be approximately 83.2 degrees. On the opposite side, the angles are each approximately 96.8 degrees. A design can be provided in which several openings of this type are provided in the anisotropically etched silicon component, each of which forms a separately formed installation space for accommodating one or more optical components.

[0028] The cover substrate can at least partially fill the installation space. The cover substrate can partially or completely fill the installation space. For example, epoxy resin or silicone can be introduced into the installation space as the cover substrate. Alternatively, the installation space is free of the cover substrate, in which case the installation space can be designed as a cavity in which the optical component is arranged. In particular, a section of the cavity below the exit opening can be free of the cover substrate.

[0029] The light-reflecting surface may have a surface-side mirror coating. The surface-side mirror coating may be created, for example, using metallization or a dielectric mirror.

[0030] The optical component can have a side optical output / input through which light can exit / enter in a horizontal direction. The deflection of incoming or outgoing light rays occurs at the light-reflecting surface, such that a deflection between horizontal and vertical directions or vice versa occurs. If the optical component is designed as a light-emitting diode, the emitted light rays exit through a side optical output. If the optical component is designed as a photodiode, the incoming light rays enter in a horizontal direction through a side optical input, for example, an entrance window.

[0031] The optical component can be arranged on a submount arranged on the carrier substrate. The submount can be made of silicon carbide or aluminum nitride, for example.

[0032] The method for manufacturing the component arrangement may involve producing the anisotropically etched silicon component by wet-chemical etching, for example, by etching with potassium hydroxide solution (KOH). Another suitable etching solution for the anisotropic etching of silicon is, for example, tetramethylammonium hydroxide (TMAH).

[0033] To produce the package and / or to produce the package arrangement, it may be intended to use the packaging in the panel or at the wafer level.

[0034] When manufacturing using wafer-level processes, one or more circumferential silicon frames, entire cap substrates and / or a single or multiple elements with a reflective surface inclined at 45 degrees can be produced at the wafer level. The advantage is that many components / caps can be manufactured simultaneously at the wafer level. The individual caps for packaging are created after singulation, for example by sawing the cap substrate. The component can be packaged by applying an isolated cap to a board on which a chip or component is pre-mounted. The components can also be pre-mounted in a panel, i.e. several components are already mounted on a carrier substrate, which are then packaged by applying individual caps or cap arrays (separated panel with multiple cap structures from a cap substrate manufactured at the wafer level).

[0035] Wafer-level packaging, as used here, refers to the packaging of all components on a wafer in a single step using a cap substrate in wafer form. This can be the case, for example, when components are completely pre-assembled on a through-hole substrate, such as a silicon substrate in wafer form, and then all components are housed simultaneously by bonding a cap wafer. Individual packages are then created by subsequently separating the composite.

[0036] In conjunction with the package, it can be provided that, with respect to the housing in which the component arrangement is accommodated, light exits or enters centrally, essentially in the region of the exit opening / inlet opening, as viewed from a housing top. This achieves essentially central light emission / absorption for the package.

[0037] The cover substrate can be made of borosilicate glass such as Bofofloat33 or Mempax from Schott AG, quartz glass, sapphire glass, or other glasses such as AF32, D263T, BK7, or B270 from Schott AG; Eagle XG or Pyrex from Corning; SD2 from Hoya; or EN-A1 from Asahi. However, the cover substrate can also be made of silicon or germanium, for example, for applications in the IR range. The cover substrate can also have a substrate coating, such as an anti-reflection coating. The coatings can be designed for different wavelength ranges and applied to one or both sides. Filter coatings and / or opaque aperture structures for different wavelength ranges can also be provided.

[0038] Furthermore, one embodiment may provide for the integration of optical elements, for example, lenses on the cover substrate. Examples of suitable lenses include convex lenses made of polymer, glass-like materials, silicon, or germanium. The use of microstructured Fresnel lenses is also possible.

[0039] The carrier substrate contains one or more vias for the electrical contact of the optical component. The rear contacts enable subsequent assembly using SMD technology, for example, by tin / silver wave soldering or mounting with electrically conductive adhesives.

[0040] The carrier substrate can be made of silicon, ceramics such as aluminum nitride, silicon carbide, aluminum oxide, LTTC (low-temperature cofired ceramics) or HTCC (high-temperature cofired ceramics), glass, or DBC (direct bonded copper) substrates. Furthermore, the use of metal substrates, such as IMS (insulated metal substrates) made of copper, aluminum, or other metals, is also possible. The use of carrier substrates made of plastics such as FR4 is also conceivable.

[0041] A connection between spacer and carrier substrate can be achieved, for example, via a solder bond, preferably via a eutectic bond. For this purpose, a metal combination with a preferably eutectic composition is applied to the carrier substrate or the back of the spacer, for example, gold and tin, copper and tin, gold and germanium, tin and silver, gold and indium, copper and silver, or gold and silicon. This metal combination forms a eutectic bonding phase in a soldering process and connects the spacer to the carrier substrate. The spacer and carrier substrate are provided with an appropriate base metallization for the soldering process. The metal combination for the eutectic joining can, for example, be provided as a preform. Alternatively, the metal combination can be applied as a paste or electroplated to one of the joining partners.

[0042] For example, in the case of thin metal layers, it may be necessary to place a so-called alloy stop layer beneath the actual bonding phase. For example, layers of platinum or nickel, or even alloys of chromium and nickel, are suitable for the eutectic joining of gold and tin.

[0043] A direct bonding process can also be used, taking advantage of very high surface qualities of Ra < 1nm. This can be a direct fusion bond, which can be hydrophobic or hydrophilic depending on the surface characteristics of the bonding partners. The two bonding partners are first connected to each other via a pre-bond using van der Waals bonds. A subsequent annealing step then forms covalent bonds in the bond interface. The fusion bond can also be plasma-activated. This makes it possible to significantly reduce the thermal stress during annealing. Anodic bonding can be used as another direct bonding process.

[0044] As an alternative to the methods described, a reactive bonding process can also be used. In a reactive bond, a metal stack consisting of alternating layers is applied. This metal stack can be provided by deposition processes such as sputtering or in the form of foils. An electrical or laser-induced pulse briefly generates a high-temperature reaction that "welds" the two bonding partners together. The metal layers are bilayers, for example, made of palladium and aluminum or copper oxide and aluminum.

[0045] Solid-liquid interdiffusion bonding is also possible, for example, using metal combinations of gold and indium, gold and tin, or even copper and tin. In this process, the bonding process is determined by the diffusion of one bonding partner into the other during an annealing step. The actual bonding phase then withstands higher temperatures later on. Furthermore, permanent bonds can be created by joining gold to gold, copper to copper, or even aluminum to aluminum using (for example) thermocompression bonding. Glass frit bonding can also be used.

[0046] In the case of transparent substrates, a laser welding process can be used to join the carrier substrate and spacer, provided the surface quality of the joining surfaces is appropriate. The use of epoxy resins, silicones, or other adhesives is also conceivable.

[0047] For example, a direct bonding process can be used to join the spacer and the cover substrate. Such processes include anodic bonding or fusion bonding. Reactive bonding or adhesive bonding can also be used. Solid-liquid interdiffusion bonding is also an option. Laser welding is also suitable for joining the spacer and cover substrate. In this process, two substrates are brought into "optical contact" and then welded with a laser. It is conceivable that all of the previously mentioned joining processes for spacers and carrier substrates could also be used to join the spacer and cover substrate.

[0048] The embodiments described in connection with the component arrangement can be provided accordingly in connection with the method for producing the component arrangement. Description of implementation examples

[0049] Further embodiments are explained in more detail below with reference to the figures of a drawing. Herein: Fig. 1 a component arrangement in which an optical component is arranged in a construction space and is connected to external contacts via a contact connection through a carrier substrate; Fig. 2 a component arrangement in which an optical component is arranged in a construction space and is connected to external contacts via a laterally leading contact connection; Fig. 3 a schematic representation of a component arrangement in which the installation space with the optical component is filled with a cover substrate; Fig. 4 a schematic representation of a component arrangement in which a cladding is formed with the cover substrate filling the installation space with the optical component; Fig. 5 a schematic representation of a component arrangement in which a light-reflecting surface is provided in the installation space by means of an anisotropically etched silicon component which is arranged at a distance from a spacer in the installation space; Fig. 6 is a schematic representation of a spacer designed as a frame, which is formed by an anisotropically etched silicon component; Fig. 7 a light microscopic top view of an etched frame structure in which a masking opening is selected for an anisotropic wet chemical etching process with a compensation structure; Fig. 8 is a schematic representation of a section of a wafer having a plurality of openings, each of which can be used to form a component arrangement to produce a cap array; Fig. 9 a schematic representation of spacers, each formed with an anisotropically etched silicon component, wherein a central positioning of the mirror surface in a frame geometry allows a central exit / entry of the light; Fig. 10 is a schematic representation of an arrangement with a spacer formed by an anisotropically etched silicon component, on which a cover substrate is arranged, wherein the spacer has a rear-side structured bonding surface, for example a metallization, on a lower side; Fig. 11 a schematic representation of an arrangement in which a section of a glass fiber for coupling in / out light is arranged opposite the light-reflecting surface. Fig. 12 is a schematic representation of an arrangement in which two individual mirror elements are arranged in a housing; Fig. 13 a schematic representation of two components that have been manufactured in the panel or by means of wafer-level packaging; Fig. 14 is a schematic representation of an arrangement in which the installation space is formed by a spacer element having a flank angle of the mirror surfaces of approximately 54.7 degrees; Fig. 15 is a schematic representation of a component in which the spacer element and the carrier substrate are made from one piece and the through contacts are provided by means of a dry etching process; Fig. 16 is a schematic representation of a component in which the spacer element and the carrier substrate are manufactured from one piece and the through contacts are provided by means of a wet-chemical etching process; Fig. 17 a schematic representation of a component in which the walls of the installation space are approximately vertical with the exception of a 45-degree mirror plane; Fig. 18 is a schematic representation of a component arrangement in which a lens is arranged on the cover substrate; Fig. 19 a schematic representation of a component arrangement with a circumferential spacer element with a mirror plane in combination with a single mirror element; Fig. 20 is a schematic representation of a component arrangement in which a lower opening in the spacer, which is designed as an anisotropically etched silicon component, is designed with a nearly vertical chamfer; and Fig. 21 a schematic representation of a component arrangement in which a lower opening in the spacer, which is designed as an anisotropically etched silicon component, is designed with an undercut relative to the surface of the spacer.

[0050] Fig. Figure 1 shows a component arrangement in which an optical component 2 is arranged on a carrier substrate 1 in a construction space 1a. The optical component 2 is, for example, a light-emitting or light-receiving diode, such as a laser diode or a photodiode. A spacer 3 made of silicon is provided. A cover substrate 4 is arranged on the spacer 3.

[0051] In the exemplary embodiment, the optical component 2 is mounted on a submount 5, for example, a submount made of silicon carbide or aluminum nitride. Alternatively, the optical component 2 can be arranged directly on the carrier substrate 1. The optical component 2 can be mounted on the submount 5 or directly on the carrier substrate 1 using eutectic soldering, for example, gold and tin. However, other methods such as gold or indium bonding or sinter bonding can also be used. The chip can be mounted either using a flip-chip process, by contacting with wire bonds, or a ground contact in combination with wire bonds.

[0052] The silicon spacer 3 is manufactured by anisotropic KOH etching from a silicon single crystal tilted approximately 9.7 degrees to the 100 crystal orientation (off-oriented). This results in a 111 crystal plane with a slope 6 at an angle of approximately 45 degrees to the surface. The opposite plane then forms at an angle of approximately 64.5 degrees. The lateral crystal planes can, for example, have an angle of approximately 55.3 degrees.

[0053] The spacer 3, which is designed as an anisotropically etched silicon component, has a metallic mirror coating 6a in the embodiment shown. Alternatively, another optical (light-reflecting) layer can be provided, for example a dielectric mirror for specific wavelengths. For the optional metallic mirror coating 6a, aluminum can be used in the UV range, silver in the visible range, and gold in the IR / NIR range. A metallic mirror coating made of copper is advantageous from the "red" wavelength range (wavelengths greater than approximately 600 nm). Alternatively, the inclined side walls in a cavity can also be provided with different coatings. For example, the side walls that are different from 45 degrees can be provided with a particularly opaque / light-absorbing layer for the desired wavelength range in order to avoid reflections in the installation space.

[0054] The 45-degree inclined, naturally grown monocrystalline 111 planes (light-reflecting surfaces / mirror surfaces) produced by the previously described wet-chemical etching process are very smooth compared to other manufacturing processes such as machining or dry etching. This results in beam deflection with very low scatter and loss.

[0055] The optical component 2 mounted on the carrier substrate 1 can be a side-emitting component, for example, a laser diode. The 45-degree slope 6 allows light emerging horizontally from the side of the optical component 2 to be emitted vertically by means of appropriate deflection.

[0056] The cover substrate 4 can be made of, for example, borosilicate glass such as Borofloat33 or Mempax from Schott AG, quartz glass, sapphire glass, or other glasses such as AF32, D263T, BK7, or B270 from Schott AG; Eagle XG or Pyrex from Corning; SD2 from Hoya; or EN-A1 from Asahi. The cover substrate 4 can also be made of silicon or germanium, for example, for applications in the IR range. The cover substrate 4 can additionally have a substrate coating, for example, an anti-reflection or filter coating. The coatings can be designed for different wavelength ranges, single-sided or double-sided, and optionally structured. Opaque structured coatings can also be used for the wavelength ranges, for example, to form apertures.

[0057] Furthermore, in one embodiment, the integration of optical elements can be provided, for example, lenses on the cover substrate 4. Here, for example, convex lenses made of polymer, glasses or other glass-like materials, silicon or germanium come into consideration (see Fig. 18). The use of microstructured Fresnel lenses is also possible.

[0058] In the carrier substrate 1, vias 7, connected to one or more bond connections 2a, are provided for the electrical contact of the optical component 2. In addition to the bond connection 2a, this embodiment also includes a ground contact 2b, which is also connected to a via 7. The rear contacts 8 enable subsequent assembly using the SMD design, for example, using tin-silver wave soldering.

[0059] The carrier substrate 1 can be made, for example, of silicon, ceramics such as aluminum nitride, silicon carbide, aluminum oxide, LTTC (low-temperature cofired ceramics) or HTCC (high-temperature cofired ceramics), glass, or DBC (direct bonded copper) substrates. Furthermore, the use of metal substrates, for example, IMS (insulated metal substrates) made of copper, aluminum, or other metals, can be considered. The use of carrier substrates made of plastics such as FR4 is also conceivable.

[0060] A connection 9 between spacer 3 and carrier substrate 1 can be established, for example, via a solder bond, preferably via a eutectic bond. For this purpose, a metal combination with a corresponding eutectic composition, such as gold and tin, copper and tin, gold and germanium, tin and silver, gold and indium, copper and silver, tin with silver and copper, or even gold and silicon, is applied to the carrier substrate 1 or the back of the spacer 3. This forms a eutectic bonding phase between the spacer 3 and the carrier substrate 1 during the subsequent soldering process. In order to achieve the best possible layer adhesion of the metal combinations to the carrier substrate 1 or the spacer 3, a layer of pure titanium, tungsten titanium, or tungsten titanium nitride can be arranged beneath the applied metal stack. The latter has the advantage of representing a diffusion barrier compared to gold.The bonding partner must be provided with a counter-metallization for the joining process in order to ensure good wetting of the connection phase that forms during the soldering process.

[0061] In principle, lead-containing solders can also be used for joining the carrier substrate 1 and spacer 3. A further joining method can be a sintering process, for example, silver or gold sintering.

[0062] Additionally, for example, in the case of thin metal layers, it may be necessary to place a so-called alloy stop under the actual bonding phase. In the case of eutectic bonding with gold and tin, for example, layers of platinum, nickel, or even alloys of chromium and nickel are suitable for this purpose.

[0063] A direct bonding process can also be used to achieve very high surface qualities of Ra < 1 nm. This can be a direct fusion bond, which can be hydrophobic or hydrophilic depending on the surface characteristics of the bonding partners. The two bonding partners are first connected to each other via a pre-bond using van der Waals bonds. A subsequent annealing step then forms covalent bonds in the bonding interface. The fusion bond can also be plasma-activated. This makes it possible to significantly reduce the temperature stress during annealing. Anodic bonding can also be used as another direct bonding process. The latter process offers the advantage that the requirements for the surface quality of the bonding partners are less demanding than with fusion bonding.

[0064] As an alternative to the methods described, a reactive bonding process can also be used. In a reactive bond, a metal stack consisting of alternating metallic layers is applied. An electrical or laser-induced pulse briefly generates a high-thermal reaction that "welds" the two bonding partners together. The metal layers are bilayers, for example, made of palladium and aluminum or copper oxide and aluminum. Solid-liquid interdiffusion bonding, for example, with metal combinations of gold and indium, gold and tin, or even copper and tin, is also possible. In this process, the bonding process is determined by the diffusion of one bonding partner into the other during an annealing step. The actual bonding phase then withstands higher temperatures later on. Alternatively, glass frit bonding can also be used.

[0065] For the connection 10 between spacer 3 and cover substrate 4, a direct bonding process can be used, for example. Such processes include anodic bonding or fusion bonding. In the case of anodic bonding, the direct joining of silicon to the cover substrate made of an alkali-containing glass can be provided. Alternatively, the anodic joining of aluminum to the cover substrate made of an alkali-containing glass is also possible. In this case, the mirror coating on the 45-degree mirror surface is not provided in a structured manner, meaning that the upper side of the silicon spacer is completely coated with aluminum.

[0066] Reactive bonding or adhesive bonding can also be used. Solid-liquid interdiffusion bonding is also an option. Laser welding is also suitable for joining spacers and cover substrates. In this process, two substrates are brought into "optical contact" and then welded with a laser. The joining of spacers and cover substrates can also be achieved using a thermocompression bond, for example, with metal combinations of gold to gold, copper to copper, or even aluminum to aluminum.

[0067] Depending on the bonding method, the housing is hermetic or quasi-hermetic.

[0068] Fig. Figure 2 shows the arrangement of the optical component 2 with a lateral contact. Conductor tracks 11 are applied to the carrier substrate 1 and extend outward beneath the spacer 3. The spacer 3 and the contact are separated from each other by an electrical insulation layer 12. This layer can be made of SiOx or silicon nitride, for example. The connection between the cap and the board, or the insulation layer, is established, for example, by a eutectic metal bond.

[0069] Fig. Figure 3 shows the component arrangement without the cover substrate 4. Here, the build space 1a is filled with, for example, an epoxy resin or silicone, and is quasi-hermetic. This arrangement can be used, for example, for short-pulsed lasers. The connection to the carrier substrate can also be achieved by adhesive bonding.

[0070] Fig. Figure 4 also shows a component arrangement without a cover substrate. In this version, not only the build space 1a is filled, but the entire component is "overmolded."

[0071] Fig. Figure 5 shows an arrangement of a side-emitting component in a ceramic package, for example. In this package, a single anisotropically etched silicon component 50 is provided in the build volume 1a to deflect the beam, serving as a mirror element. This type of arrangement can also be provided for conventional TO packages.

[0072] Fig. Figure 6 shows a top view of the anisotropically etched structure of a mirror frame 60. An opening 61 in the silicon, created by the tilt of the crystal, is trapezoidal and axially symmetric in one direction. The corner angles on the longer side with the 45-degree mirror plane are approximately 83.2 degrees each. On the opposite, shorter side, the angles are approximately 96.8 degrees each.

[0073] Fig. Figure 7 shows a plan view of an anisotropically etched structure of a mirror frame 70. In this case, a masking opening for the anisotropic etching process is not selected along the trapezoidal 111 crystal planes (compare Fig. 6), but with a compensation structure. This results in the upper opening of the etching pit being smaller than Fig. 6 is not completely trapezoidal, but is limited in one direction of its extension. This makes it possible to reduce the lateral dimension of the openings and thus arrange a larger number of etched structures on the silicon substrate. Depending on the application, various compensation structures can be realized.

[0074] Fig. Figure 8 shows an arrangement of multiple openings in the form of an array 80. This arrangement allows multiple components to be encapsulated simultaneously in the panel, thus increasing, for example, the luminous efficacy of the component arrangement in a space-saving manner. This is particularly advantageous for systems with high light output. The array 80 can be designed either as a panel of pure spacers 3 with a 45-degree mirror surface or, in combination with a cover substrate, as a panel of encapsulations with a 45-degree mirror surface.

[0075] Fig. Figure 9 shows a circumferential spacer 3, which is designed as an anisotropically etched silicon component with a 45-degree mirror surface. In this embodiment, the spacer 3 is designed so that a light beam can exit or enter the package centrally ("center emission"). Such spacers 3 can also be designed with a cover substrate as encapsulation (compare Fig. 10).

[0076] Fig. Figure 10 shows a semi-finished product comprising a spacer 3, which is designed as an anisotropically etched silicon component with a 45-degree mirror surface and cover substrate. A structured bonding surface, such as a metallization, may be provided for joining to a carrier substrate 1. Various embodiments of this arrangement and corresponding methods for connecting spacer 3 and a carrier substrate 1 are described in the embodiments for Fig. 1. This applies analogously to the joining of spacer 3 and cover substrate.

[0077] Fig. Figure 11 shows an arrangement in which a silicon element with a 45-degree mirror surface is used to couple a waveguide, such as a fiber optic cable. This allows light to be coupled out of the package or coupled into another waveguide (signal redirection).

[0078] Fig. Figure 12 shows an arrangement of a side-emitting component, for example a laser diode or an LED, for example in a ceramic package. In comparison to Fig. 5, this embodiment provides for the placement of multiple silicon elements with 45-degree mirror surfaces. This is advantageous when the side-emitting component emits light laterally in multiple directions. Laterally emitting light beams in one direction can also be provided, for example, to calibrate the laser diode via another monitor photodiode built into the package.

[0079] Fig. 13 shows an arrangement in which components 130, 131 are arranged in adjacent and separately formed installation spaces 132, 133. In this embodiment, the components 130, 131 are packaged at the wafer level. For this purpose, a carrier substrate made of silicon, for example, can be provided. The carrier substrate 1 made of silicon is prepared with vias 7. The vias 7 can be realized, for example, by dry or wet etching processes with subsequent metal filling of the holes using an electroplating process. In addition, contacts for a component are provided on a front side of the carrier substrate, and contacts for later assembly in SMD construction are provided on the back. For the electrical insulation of the vias, the carrier substrate 1 made of silicon can be passivated by an inorganic layer before the electroplating deposition and the creation of the contacts.For this purpose, thermal oxidation of the silicon, the deposition of a nitride layer using an LPCVD process, or other CVD processes (e.g., PECVD – plasma-enhanced CVD) for the deposition of insulation layers are conceivable. Before the metal filling of the vias is electroplated, an electrically conductive "seed" layer must be applied to the previously deposited passivation layer. This can be achieved, for example, using sputtering processes.

[0080] In this embodiment, a plurality of components are first mounted serially on a prepared carrier substrate 1, which can be in the form of a wafer or a rectangular panel, and then joined in a further step by applying a cap wafer or cap array at the wafer level or as a panel. This simultaneously forms a plurality of encapsulated components. The individual packages are then created by separating the assembly.

[0081] Fig. Figure 14 shows an arrangement in which the spacer 3 was manufactured from a single-crystal silicon uninclined to the 100 orientation by anisotropic wet-chemical etching. As a result, the 111 crystal planes are all formed at an angle of approximately 54.7 degrees. In this configuration, the upward light exit from the package in several directions is favored. The fabrication is as previously described in Fig. 13 can also be represented as a housing using wafer-level packaging.

[0082] Fig. Figure 15 shows an arrangement in which the spacer 3 and the carrier substrate 1 are manufactured entirely in one piece from silicon. In this process, a cavity is etched into the silicon substrate on the front side using anisotropic wet-chemical structuring. This cavity is connected to the back side with dry-etched vias. The silicon substrate 1 is made of silicon as for Fig. 13 described electrically insulated.

[0083] Fig. Figure 16 shows an arrangement in which the spacer 3 and the carrier substrate 1 are manufactured entirely in one piece from silicon. In this process, a cavity is etched into the silicon substrate on the front side by means of anisotropic wet-chemical structuring. This cavity is connected to vias 7 on the back side, which, compared to Fig. 15 are manufactured by anisotropic wet chemical etching. The silicon substrate 1 is as in Fig. 13 described electrically insulated.

[0084] Fig. Figure 17 shows a configuration in which the build space was first etched approximately vertically using dry etching. In a subsequent wet-chemical anisotropic etching step, a 45-degree surface is formed, which can be used as a mirror plane. This design has the advantage that the combination of different etching processes allows the area coverage on a substrate to be further increased.

[0085] Fig. Figure 18 shows a component on which a lens arrangement 180 is additionally arranged on the cover substrate 4. This embodiment is in connection with Fig. 1 described in more detail.

[0086] Fig. Figure 19 shows a schematic representation of a component arrangement in which a 45-degree mirror plane is provided on the surrounding spacer 3 (silicon frame). A further element 190, which is designed as an anisotropically etched silicon component, with an inclined surface 191 also at 45 degrees, is arranged on the carrier substrate 1 before the cap is mounted on the carrier substrate. The inclined surface 191 provides a light-reflecting surface, which in the embodiment shown has a mirror coating 191a.

[0087] Fig. 20 shows a schematic representation of a component arrangement in which a lower opening 200 in the spacer 3, which is embodied as an anisotropically etched silicon component, is embodied with a chamfer 201, which in the example shown is oriented substantially vertically. This has the advantage, on the one hand, of reducing the installation space 1a and thus the overall size of the package; on the other hand, it makes it possible to arrange a side-emitting component closer to the light-reflecting mirror surface. This promotes the impingement of a light beam, widened by any beam divergence, onto the provided mirror surface. In this way, light emerging laterally from the component can be guided even more effectively out of the installation space 1a, and the component height can be further reduced. In this embodiment, the chamfer 201 on the lower opening 200 of the spacer 3 is realized, for example, by a dry etching process.However, it can also be provided to achieve the chamfer 201 by wet-chemical overetching of the spacer 3, since in the anisotropic etching process, essentially perpendicular crystal planes with respect to the 100 orientation are established at convex edges of the spacer 3 made of silicon.

[0088] Fig. Figure 21 shows a schematic representation of a component arrangement in which a lower opening 210 in the spacer 3, which is designed as an anisotropically etched silicon component, is designed with an undercut 211 relative to the surface of the spacer 3. This offers the same advantages as for Fig. 20 already described. The undercut 211 can be designed as shown in Fig.20 can be achieved by suitable dry etching processes, on the other hand, a wet-chemical anisotropic etching of the back of the spacer 3 is provided, in which the opening and thus the undercut 211 are predetermined by a corresponding masking.

[0089] The features disclosed in the above description, the claims and the drawings may be important for the realization of the various embodiments both individually and in any combination.

Claims

[1] Component arrangement, with - a carrier substrate; - a spacer which is arranged on the carrier substrate surrounding a construction space and has an outlet opening on a side facing away from the carrier substrate; - an optical component which is arranged in the installation space; - a contact connection that electrically connects the optical component to external contacts that are arranged outside the installation space; - a cover substrate which is arranged on the spacer and with which the exit opening is covered in a translucent manner; and - a light-reflecting surface formed on an anisotropically etched silicon component and arranged in the construction space as an inclined surface at an angle of approximately 45° to the surface of the carrier substrate facing the construction space, such that light irradiated horizontally onto the light-reflecting surface can be radiated vertically through the opening and the cover substrate, and vice versa; wherein the optical component is arranged in the construction space within an upper opening of the anisotropically etched silicon component, which opening, when viewed from above, has an incomplete trapezoidal shape that is limited in one direction of its extension. [2] Component arrangement according to claim 1, characterized by that the anisotropically etched silicon component is arranged in the installation space surrounded by the spacer. [3] Component arrangement according to claim 1, characterized bythat the spacer is at least partially formed with the anisotropically etched silicon component. [4] Component arrangement according to claim 3, characterized by that a first wall surface of the spacer, which faces the installation space and is arranged outside an area with the light-reflecting surface, is inclined to the vertical direction at a first angle different from 45°. [5] Component arrangement according to claim 4, characterized by that a second wall surface of the spacer, different from the first, which faces the installation space and is arranged outside the area with the light-reflecting surface, is inclined to the vertical direction at a second angle different from 45°, which is different from the first angle. [6] Component arrangement according to at least one of the preceding claims, characterized by that the cover substrate at least partially fills the construction space. [7] Component arrangement according to at least one of the preceding claims, characterized by that the light-reflecting surface has a surface-side mirror coating. [8] Component arrangement according to at least one of the preceding claims, characterized by that the optical component has a lateral optical exit / entrance through which light can exit / enter in a horizontal direction. [9] Component arrangement according to at least one of the preceding claims, characterized by that the optical component is arranged on a submount which is arranged on the carrier substrate. [10] Method for producing a component arrangement, comprising: - producing an anisotropically etched silicon component from a silicon single crystal by means of anisotropic etching, wherein the silicon single crystal is tilted by approximately 9.7° to the 100 crystal orientation, such that a 111 crystal plane with a slope of approximately 45° is formed; and - Producing a component arrangement according to at least one of the preceding claims using the anisotropically etched silicon component, wherein a light-reflecting surface is formed with the 111 crystal plane having the inclination of approximately 45° in the component arrangement. [11] Package, with a component arrangement according to at least one of claims 1 to 9 and a housing in which the component arrangement is accommodated. [12] Package according to claim 11, characterized by that a substantially central light exit / light entry is formed in the region of the exit opening with respect to the housing with a view to a housing top. [13] Package arrangement, with a planar arrangement of several packages according to claim 11 or 12. [14] A method for manufacturing a package according to claim 10 or 11, wherein the package is manufactured by wafer level packaging. [15] A method for manufacturing a package assembly according to claim 13, wherein the package assembly is manufactured by wafer level packaging.

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