Hermetically sealed glass package

Abstract

The present invention provides a package for thermally sealing functional regions, comprising: a bottom substrate; a cover substrate, wherein the bottom substrate and the cover substrate together form at least a portion of the package or form the package; at least one functional region, such as a cavity, hermetically sealed by the package, wherein the package includes at least one laser bonding line, and the substrates of the package are hermetically bonded to each other through the at least one laser bonding line; wherein the laser bonding line has a height HL perpendicular to its bonding surface; wherein heat can be generated in the functional region of the package; and wherein at least the bottom substrate and / or the cover substrate are in the form of thermal insulators.

Description

Technical Field

[0001] The present invention relates to a hermetically sealed, particularly multi-sealed, glass encapsulation, and a method for providing a hermetically sealed glass encapsulation. Background Technology

[0002] Hermetically sealed packages, also known as housings, enclosures, or shells, can be used to protect sensitive electronic devices, circuits, or sensors. These packages enable the application of medical implants, such as in the heart region, the retina, or in bioprocessors. Bioprocessors made of titanium are known and are currently in use.

[0003] The encapsulation according to the invention can protect the sensor from particularly adverse environmental conditions. This field also includes microelectromechanical systems (MEMS), barometers, blood gas sensors, glucose sensors, etc.

[0004] Another application area of ​​the package according to the invention can be found in the fields of smartphone casings, virtual reality glasses, and similar devices. For example, in the context of electric vehicles, the package according to the invention can also be used in the production of flow batteries. Moreover, the package according to the invention can also be applied in the aerospace industry, high-temperature applications, and micro-optics.

[0005] The common thread among the aforementioned intended uses is the need for electronic devices to meet high requirements in terms of robustness. To enable the use of electronic devices that are not expected to withstand such external shocks, the package must be protected from these adverse environmental influences. Furthermore, it may be necessary to ensure communication with the interior of the package, for example, within the visible range and / or the microwave radiation range—that is, communication with the cavity defined by the package (e.g., containing electromagnetic radiation). This means that the package should be at least partially transparent, i.e., transparent in at least a portion of its portion, and / or transparent for at least certain wavelength ranges. This transparency enables communication processes, data or energy transmission, and the measurement or utilization of electronic devices or sensors disposed within the cavity. In particular, it enables optical communication technologies or optical data and energy transmission.

[0006] In principle, it is known to combine multiple parts and arrange them such that a receiving area is formed in the intermediate space, which can accommodate the parts. For example, a method for producing a transparent part for protecting optical components is disclosed by reference to European Patent EP 3 012 059B1, which is incorporated herein by reference. For this purpose, a novel laser process is used.

[0007] The problem is that, for example, when used as a biological implant, the release of large amounts of heat from the encapsulation over a short or long period of time can cause damage to the vicinity of the biological implant. Known research has addressed the effects of heat on various tissue types and generally assumes that localized damage has occurred when the local temperature exceeds 43 degrees Celsius, which may have already led to cell death, depending on the location of the damage. For example, in the event of a malfunction (such as a short circuit in a semiconductor component or battery), temperatures exceeding 100 degrees Celsius can be reached for a short period. Summary of the Invention

[0008] Therefore, the present invention relates to the scope of research on improving encapsulations and, in particular, making encapsulations more robust. In other words, the object of the present invention is to provide an improved encapsulation that reduces the temperature load on adjacent locations, for example, to prevent cell damage.

[0009] This can be achieved by reducing, delaying, or controlling the heat dissipated from the package into the environment. Optionally, the package according to the invention can use cheaper components because it provides protection. In particular, the invention can use components with lower manufacturing costs and greater fault tolerance because it can tolerate component failure when the component no longer generates temperature spikes (e.g., in tissue).

[0010] Another aspect of the invention is based on the understanding that, in the case of hermetically sealed package solutions, special provisions may have to be made to dissipate any heat that may be generated in the package over a long period of time, such as heat from power semiconductors.

[0011] Therefore, the package according to the invention is designed for thermal encapsulation of functional areas. In other words, the package is thermally insulated to prevent heat from escaping from the package to the environment, especially thermal spikes that may occur, for example, in the event of a malfunction of electronic components within the package. For this purpose, the package includes at least one bottom substrate and a cover substrate, the bottom substrate forming at least a portion of the package or forming the package together with the cover substrate. Furthermore, the package includes at least one functional area, such as a cavity, hermetically sealed by the package.

[0012] The package includes at least one laser bonding line, such that the substrates of the package are hermetically bonded to each other via the at least one laser bonding line. Each laser bonding line has a height HL perpendicular to its bonding surface. Preferably, the height HL of the laser bonding line extends into the material of the substrate disposed above the laser bonding line. On the opposite side, the laser bonding line extends into the material of the substrate disposed below the laser bonding line. For example, a cover substrate is fused to a bottom substrate. In other words, during the bonding step or within the laser bonding line, the material of one substrate melts and mixes with the material of another substrate to create a strong and non-removable hermetically sealed bond between the two substrates.

[0013] In another example, at least one intermediate substrate is disposed between the bottom substrate and the cover substrate, and in this case, the bottom substrate is bonded to the intermediate substrate in a first bonding surface by at least one first laser bonding line, and the cover substrate is bonded to the intermediate substrate in a second bonding surface by at least one second laser bonding line.

[0014] For example, power electronic components located in the functional area (which generate heat during operation) may generate heat in the functional area of ​​the package, or if an electronic component within the package fails (accompanied by a thermal spike), heat may be generated in the functional area of ​​the package.

[0015] If the encapsulation dissipates heat outwards in an unimpeded manner, this peak thermal load—a high thermal energy level over a short period—can cause temperature increases at certain points or in certain areas near the encapsulation. For example, if the encapsulation is located in the body (i.e., tissue), such temperature increases can lead to cell damage or even cell death. It is generally believed that, for example in the case of human tissue, cell damage and cell death can occur at threshold temperatures above 43 degrees Celsius; see, for example, “Thresholds for thermal damage to normal tissues: an update,” P. Yarmolenko et al., *Int. J. Hyperthermia*, 2011, pp. 320–343.

[0016] On the other hand, if a power semiconductor malfunctions, the local temperature within the semiconductor component can well exceed 100 degrees Celsius and may even exceed the semiconductor component's melting temperature. For example, in this example of a defect in a semiconductor component intended for use as a biological implant in human tissue, an encapsulation could be applied to protect the human tissue from cell damage, allowing the generated heat to dissipate to the surrounding tissue over a prolonged period, thereby reducing the peak temperature to a critical temperature sufficient not to exceed 43 degrees Celsius.

[0017] In the most general case, this can be achieved by providing at least a bottom substrate and / or a cover substrate in the form of thermal insulation, so that the heat generated within the package is not released into the environment or is released relatively slowly.

[0018] The package may preferably include at least one intermediate substrate. In this case, one or more functional regions may be arranged on the intermediate substrate.

[0019] The bottom substrate, one or more intermediate substrates, and the cover substrate can all be in the form of thermal insulators, such that the entire housing of the package preferably acts as a thermal insulator.

[0020] The bottom substrate is preferably made of a material with low thermal conductivity. The bottom substrate, one or more intermediate substrates, and / or the cover substrate may comprise vitreous materials, such as glass, glass-ceramic, silicon, sapphire, or combinations thereof. For example, glass or vitreous materials have proven particularly advantageous because they have excellent biocompatibility and chemical compatibility with the human body, are known to have no interaction with the human organism, and provide excellent insulating properties. Furthermore, the glass can be made radiation-transparent, enabling wireless data exchange, for example, through radiation or wave information, or optionally through contactless charging of electronics or batteries disposed within the package. If the substrate (e.g., the cover substrate) is a substrate transparent in the optical wavelength range, such as an optically transparent substrate, the package can be powered optically, for example, by using photovoltaic cells disposed within the package or different types of optical receivers. Therefore, the package can be described as a self-sufficient package.

[0021] To create, for example, a hermetically sealed area around a functional region, one of the laser bonding lines can, for example, circumferentially surround the functional region at a distance DF from it. In one example, the distance DF around the functional region is consistent, such that the laser bonding line extends around the functional region at approximately the same distance from all sides of the functional region. However, the distance DF may vary depending on the application. From a manufacturing technology perspective, this may be more advantageous, for example, when multiple packages are joined simultaneously in the same processing step and straight bonding lines or laser bonding lines are generated along the respective contact areas of each package. This may also be the case, for example, if the functional region or package is circular or has an arbitrary shape and the laser bonding line for the hermetically sealed functional region is drawn in a straight line. In a specific example, the functional region may be in the form of a cavity, and the cavity may have optical properties, such as being shaped like a lens (e.g., a condenser lens), and the laser bonding line may be drawn around the cavity in a pattern different from the cavity.

[0022] The functional areas of the package are adapted to accommodate at least one receptacle item, such as an electronic circuit, sensor, or MEMS, such that at least one receptacle item is disposed within the package. The at least one receptacle item may include a power semiconductor chip, such as a GaN LED, a SiC power transistor, a GaAs power transistor, or a GaN power transistor.

[0023] The article is preferably disposed in a cavity, all sides of which are (i.e., completely) surrounded by an encapsulation. The functional area or cavity can be introduced into the bottom substrate, for example, by creating grooves in the bottom substrate (e.g., by grinding), such that the bottom and sides of the functional area and / or at least one article are surrounded by the material of the bottom substrate. The functional area or cavity can also be disposed above the bottom substrate. The cavity has a bottom side, a laterally surrounding edge, and a top side. Alternatively, the top side can be described as a first side, the bottom side as a second side opposite to the first side, and the edge as an intermediate region between the first and second sides, wherein the edge generally extends substantially perpendicular to the first and / or second sides. Moreover, the height of the edge can be 0, such that in this case, the top side will be directly supported on the bottom or lower side, for example, when the functional area comprises only a thin functional layer.

[0024] The package may also include multiple cavities, for example, for accommodating at least one receptacle within a respective cavity. In other words, the receptacles within the package can be distributed across different cavities, thereby spatially separating components within the same package from each other. For example, a battery or accumulator can be accommodated in this way, optionally mounted within the package and separated from other components. This avoids, for example, damage or destruction of other components by the generated heat in the event of component failure. For example, if a power transistor overheats, the battery or accumulator can be protected against overheating and heat release. Therefore, overall, less heat accumulates or dissipates into the environment, and the overall temperature of the package remains low, thus reducing or preventing cell damage in the case of biological implants.

[0025] Therefore, heat dissipated from the package into the environment can be reduced by distributing components or housings into different cavities, thus preventing a "chain reaction" where, for example, other components fail and release additional heat when the first component fails. On the other hand, distributing housings into different cavities also provides additional protection for the respective components. For example, a memory component can be housed in its own cavity, so that even if a component in the package (such as a power transistor) fails, the memory component may still be safely read or removed.

[0026] Furthermore, alternatively or additionally, an insulating medium may be included in one or more cavities to improve insulation. In other words, the cavities are filled with an insulating medium different from glass. The insulating medium is, for example, a fluid (e.g., an insulating liquid) or an insulating gas. The term "insulating medium" also refers to the evacuation state of one or more cavities, i.e., one or more cavities are "vacuum," as vacuum is also very suitable as an insulating medium. Since one or more cavities are most advantageously hermetically sealed by laser welding, it is possible to ensure that the one or more cavities remain filled with an insulating medium or a vacuum for an extended period.

[0027] In other words, preferably, multiple containers are provided in the package and the containers are distributed into different cavities.

[0028] The hermetically sealed package preferably includes, for example, a glass channel in an intermediate substrate separating at least two cavities. The glass channel is provided for electrical connection of contained articles disposed in the different cavities. The glass channel is, for example, in the form of a through-glass via (TGV), and the via is filled with a conductive material.

[0029] The package may include at least one electrical connection layer on at least one intermediate substrate. In this case, it is particularly easy to arrange components or housing articles in the respective cavities and electrically connect them. For example, the electrical connection layer is disposed on the bottom of one or more cavities and makes contact with one or more glass vias.

[0030] In fact, packages that include cavities in which one or more components can be arranged are preferred embodiments. However, packages according to the invention are not limited to embodiments including cavities, because functional regions can have or perform functions without including cavities in the sense of hollow spaces. One example of such functional regions is the application of an electrical connection layer on a substrate, which already defines a functional region without cavities. Such an electrical connection layer can, for example, electrically connect two other functional regions, such as two cavities.

[0031] The substrate may also comprise multiple layers, and thus may be a multilayer laminate or composite. This multilayer composite (one layer of the multilayer defining the package) can then be bonded to one or more other substrates using a laser welding process. Therefore, this could mean that the multilayer composite is pre-prepared, for example, by applying a coating to a substrate and thus creating a two-layer composite, and that the two-layer or multilayer composite is bonded as a single unit to one or more layers in a package manufacturing process for producing the package.

[0032] The use of multilayer composites in a package allows the package to possess additional material properties. For example, the multilayer composite may already have internal stress or prestress or prestress direction, allowing the amount of internal stress to be increased during laser welding of the multilayer composite to at least one other layer of the package. This can improve the durability of the package, for example, if a pre-tempered multilayer composite is used. This may allow the package as a whole to have the characteristics of a tempered package. Alternatively, the multilayer composite may include one or more coatings, such as coatings that could complicate matters if they must be joined using a laser welding process. In other words, the substrate provided in the form of a multilayer composite is provided as a “stack” or “layer stack” comprising layers already bonded together. It may include an optical coating.

[0033] Laser welding is used to bond substrates together. The laser welding process can be locally controlled, resulting in only a small or negligible amount of heat penetrating into the functional areas or one or more cavities. Therefore, the laser welding process is effectively performed at room temperature, meaning the packages are bonded at room temperature.

[0034] The laser bonding line extends into the substrate material disposed above the laser bonding line, for example, beyond height HL. Within the laser bonding line, a localized melting process occurs in the material such that when the laser bonding line extends partially into the first substrate and partially into the second substrate, the two substrates are joined together by fusion. In other words, the bottom substrate,(one or more) intermediate substrates, and the cover substrate are joined together by fusion of (one or more) laser bonding lines.

[0035] In other words, laser bonding lines are provided or adapted to bridge gaps in the hermetic seal of the package, for example, by fusing two components together. When the package comprises only a bottom substrate and a top substrate for fully enclosing functional areas, the contact area between the bottom substrate and the top substrate—that is, the point, area, or interface where the top and bottom substrates are adjacent to each other—is bridged or joined by laser bonding lines. Thus, the package forms a single unit, where the interfaces between components are hermetically sealed by laser bonding lines.

[0036] In other words, to provide a package, a first substrate (bottom substrate) and at least one second substrate (cover substrate) are provided in a first step, and the at least one second substrate (cover substrate) comprises a transparent material, i.e., at least partially or a portion thereof is transparent to at least one wavelength range. The cover substrate is preferably placed directly on the bottom substrate, i.e., the cover substrate covers the cavity to be sealed, and the bottom substrate defines the respective bottom of the respective package. At least one contact area or interface is defined between at least two substrates, such that each package has at least one contact area. The cavity is then hermetically sealed by joining at least two substrates along one or more contact areas of each package (e.g., in the contact areas along lines at the edges of each package). Advantageously, multiple packages can be jointly produced, for example, from a shared starting substrate (e.g., in the form of a wafer in a wafer stack), or only a bottom substrate in the form of a wafer can be provided. Subsequently, the method for producing the packages may include cutting the individual packages by a dicing or separating step.

[0037] In this configuration, the substrate layer or bottom substrate and the cover substrate are directly stacked and in direct contact with each other, i.e., arranged adjacent to each other. Foreign matter is excluded as much as possible between the substrate layers to create the tightest possible surface contact between one substrate layer and its adjacent substrate layer. For example, in the case of two substrates, the bottom substrate is arranged to be in direct contact with the cover substrate, for example, without any other material or spacing between the bottom substrate and the cover substrate. In examples with more than two substrates, the bottom substrate is arranged to be directly adjacent to one or more intermediate substrate layers, and the cover substrate is further arranged to be directly adjacent to one or more intermediate substrate layers.

[0038] Subsequently, the substrates are bonded together using a novel laser welding process. In this case, planar substrate layers are directly bonded or joined to adjacent planar substrate layers, eliminating the need for any external materials, non-planar materials, or intermediate layers. That is, the substrates are directly bonded to each other. Laser bonding lines introduced into the two-dimensional contact area between the two substrate layers bond the directly adjacent (directly adjacent to each other) substrate layers to each other in a non-detachable manner. Therefore, the molten zone of the laser bonding line exists in both substrates and extends seamlessly from the first substrate to the adjacent second substrate, i.e., for example, seamlessly from the bottom substrate to the overlay substrate. The novel laser welding technology differs from prior art techniques that use lasers to bond substrates to each other in that the method of the present invention introduces a significantly smaller amount of heat energy into the substrate stack or package, resulting in very little heat dissipation to the rest of the package, and only a slight increase in temperature of the parts or components located within the functional areas. This is even more important because, in the case of the present invention, at least one substrate of the package has particularly good thermal insulation properties, so the heat energy applied to the package during laser welding may remain in the package for a longer period before dissipating into the environment. Therefore, only by utilizing the novel laser welding technology of the present invention in this combination is it possible to use insulating materials in packages in which parts / components are arranged or can be arranged near the laser welding line.

[0039] Therefore, for example, a direct two-dimensional or even full-surface transition is formed from one substrate layer to the next, i.e., substrate-to-substrate transition or glass-to-glass transition. A localized finite volume is formed in the form of a solder area or laser bonding line, comprising material transferred or mixed between adjacent substrate layers, for example, having a sheet-like shape. In other words, material from the first substrate (e.g., the cover substrate) permeates into the adjacent substrate (e.g., the intermediate or bottom substrate), and vice versa, i.e., material from the adjacent substrate permeates into the first substrate, such that the solder area comprises a complete mixture of materials from the adjacent substrates. Therefore, the solder area can also be referred to as a convection zone.

[0040] Of particular advantage is that the novel laser welding technology for producing irremovable glass-to-glass or substrate-to-substrate transitions eliminates the need for intermediate layers, glass flakes, foils, or adhesives that must be introduced between substrates in earlier, existing processes. More precisely, irremovable bonds can be produced without such interfering intermediate layers or additional materials. This avoids the use of additional materials, increases the achievable strength of the final product, and enables reliable hermetic sealing of functional areas or one or more cavities. The laser-welded area can be identified in the finished final product, for example, by specific localized changes in the refractive index of the material within a small fusion region.

[0041] In an advantageous embodiment, at least one of the substrates may contain markings.

[0042] The package is preferably at least partially and / or a portion thereof transparent to certain wavelength ranges. In a simple example, the cover substrate of the package is light-transmitting, i.e., transparent in the visible wavelength range. Moreover, transparency in the X-ray range may also be advantageous, for example. In other words, the cover substrate preferably comprises, for example, a vitreous material. Thus, the cover substrate is preferably transparent or transmissive to at least one wavelength range, e.g., optically transparent. Depending on the application, it may also be advantageous if the cover substrate is made opaque, i.e., optically opaque, such as frosted glass. Reduced transparency or partial translucency may also be sufficient to achieve functionality. For example, the cover substrate may comprise glass, glass ceramic, silicon, sapphire, or a combination of the above materials. In a preferred embodiment, the cover substrate is a glass plate, e.g., made of tempered glass, specialty glass, or high-temperature resistant glass from the applicant's product portfolio.

[0043] The package can be designed such that at least one functional area of ​​the package is adapted to accommodate at least one item with a size of 10mm × 10mm or smaller, preferably 5mm × 5mm or smaller, more preferably 2mm × 2mm or smaller, or even 1mm × 1mm or smaller. The size of the package will depend on the size and number of items accommodated within the functional areas or cavities of the package. For example, if a single item with a size of approximately 5mm × 5mm is provided in each of the four cavities of the package, wherein the package includes two cavities arranged adjacent to each other and two cavities stacked on top of each other, then the size of the package is typically 13mm × 13mm or larger to ensure that the item can be accommodated within the cavities.

[0044] The size specifications are determined based on practical considerations and preferred manufacturing methods, but should not in themselves be construed as size limitations given by the size of the wafer to be cut. However, using a wafer for manufacturing is only considered as an example. For instance, transparent packages can be produced using glass plates that can also have a size larger than typical wafer sizes.

[0045] The present invention also focuses on a method for providing a hermetically sealed package, the hermetically sealed package comprising a functional region, such as a cavity, enclosed by the package. The method includes the steps of: providing at least a bottom substrate and a cover substrate, wherein the cover substrate is at least partially or a portion thereof transparent to at least one wavelength range, and is therefore a transparent cover substrate; arranging at least one receiving article within the functional region, i.e., within the cavity; arranging the cover substrate on the bottom substrate above the at least one receiving article, thereby forming at least one contact area between the bottom substrate and the cover substrate, such that each package has at least one contact area; hermetically sealing the cavity by forming at least one laser bonding line along the at least one contact area of ​​each package, wherein at least one of the bottom substrate and the cover substrate is designed to be thermally insulated.

[0046] Preferably, the cover substrate is bonded to the bottom substrate via laser bonding lines. In other words, the cover substrate is placed on or within the bottom substrate without any intermediate layers and is tightly and directly bonded to the bottom substrate via one or more shared laser bonding lines. In this case, the cover substrate and the bottom substrate together form a complete package. In other words, no additional or separate parts are required to form or seal the package; instead, the bottom substrate, at least one laser bonding line, and the cover substrate hermetically and completely seal the functional area or cavity. Alternatively, it may be advantageous to use one or more intermediate substrates, for example, to separate multiple cavities from each other.

[0047] At least two substrates, or a bottom substrate and a cover substrate, are arranged or attached to each other such that they are flush against each other, and there are no other sheets, layers, or inclusions between the at least two substrates or between the bottom substrate, the cover substrate, and an optional intermediate substrate. Due to technical reasons, unavoidable minute gas inclusions may exist between the layers in the contact area, which may be caused by some possible inhomogeneities. The amount of gas trapped in the two-dimensional contact area can be further reduced by increasing pressure, such as by pressing, or by surface treatment of the substrate layers (e.g., the contact surfaces), such as by a grinding process. Pre-purging is beneficial. Depending on the process parameters and the materials to be used, filling with a gas or liquid may also be advantageous.

[0048] Particularly preferably, the width of any gap that may occur between the substrates is less than or equal to 5 μm, more preferably less than or equal to 1 μm. Such gaps can be caused, for example, by thermal shock or inclusions of particles (e.g., dust), due to tolerances in substrate manufacturing. Even with this permissible gap, which is considered to be directly adjacent in the context of this invention, laser welding can be performed such that the thickness of the weld zone is between 10 μm and 50 μm, thereby ensuring an hermetically tight seal. Similarly, in this case, the weld zone extends from the first substrate into the second substrate adjacent to the first substrate. Thus, the weld zone is introduced into the contact area between the first and second substrates, directly fusing the substrates together to form an inseparable bond. In other words, when adjacent substrates are joined in the weld zone, the materials of the two substrates melt directly in the weld zone, and the materials of the first and second substrates mix to form an inseparable integral bond. Therefore, packages produced in this manner include an integral bond between the substrates in the weld zone, i.e., a unified bond.

[0049] The contact area does not need to be optically transparent. It is also advantageous if the transparent substrate is opaque in the visible wavelength range. Only the substrate through which the laser passes to reach the contact area has at least one spectral "window" such that at least the wavelength of the laser used can be at least partially transmitted through the substrate or at least partially transmitted in the substrate. The contact area is adapted to allow the laser to deposit energy there. For example, the surfaces of two adjacent substrates can be joined by optical contact bonding and can further preferably exhibit roughness in the nanometer range. The laser radiation will be at least partially absorbed at the interface, thereby introducing energy there. In the sense of this application, the contact area is generally understood to refer to the interface on which the incident laser beam can deposit energy so that a bonding process can be performed along the contact area.

[0050] Packages produced or formed by the above methods are also within the scope of this invention.

[0051] To form laser bonding lines, a laser beam is guided around a functional area, such that the functional area is hermetically sealed circumferentially along at least one contact area. Optionally, the laser beam can be guided circumferentially multiple times, and / or alternatively, multiple laser bonding lines can be formed.

[0052] Furthermore, the use of a packaged component produced according to the above method, wherein an airtight sealed functional area or cavity is enclosed, as a medical implant or biological implant or as a sensor, is within the scope of this invention.

[0053] The invention will now be explained in more detail by way of exemplary embodiments and with reference to the accompanying drawings, wherein the same and similar elements are partially denoted by the same reference numerals, and features of different exemplary embodiments may be combined with each other. Attached Figure Description

[0054] In the attached diagram:

[0055] Figure 1 A plan view of the package is shown;

[0056] Figure 2 A cross-sectional side view of the package is shown;

[0057] Figure 3 This is a detailed view of the joint area;

[0058] Figure 4 This is a cross-sectional side view of the functional area of ​​the package;

[0059] Figure 5 This is a cross-sectional side view of the functional area of ​​a package with two cavities;

[0060] Figures 6a to 6e Exemplary steps for producing packages are shown;

[0061] Figure 7 and Figure 8 Further cross-sectional side views of the functional areas of the two packages are shown; and

[0062] Figure 9 Exemplary additional steps for producing the package are shown. Detailed Implementation

[0063] Figure 1 A plan view of the package 1 according to the invention is shown, wherein the circumferential laser-welded area 8 surrounds the functional region 13. The functional region 13 can be implemented in different ways. It can also be... Figures 3 to 8 Examples of different configurations for functional area 13 can be seen in the image. Figures 3 to 8 A cross-sectional view is shown, thus revealing the longitudinal structure of functional region 13. Various implementations of functional region 13 can be described as follows: Figure 1 This is shown schematically, as all the various implementations will be similarly represented in the schematic plan view.

[0064] The functional area can perform various tasks; for example, the functional area can be implemented as an optical receiver, or the functional area can include technical components, electromechanical components, and / or electronic components 2 disposed in the functional area 13. Multiple such tasks can also be performed in the functional area 13. The upper side of the package 1 is covered by an upper substrate 5 (e.g., a cover 5). A laser welding area 8 or at least one laser welding area 8 extends into the upper substrate 5.

[0065] refer to Figure 2The image shows a first cross-sectional view of a first embodiment of the package 1, which includes a bottom substrate 3 and a cover substrate 5. In other words, the package 1 is composed of two layers, namely the bottom layer 3 and the cover layer 5. Figure 2 The structure of a laser welding line 8 in the form of a series of multiple laser pulse impact regions 16 is also shown. The multiple laser pulse impact regions 16 are arranged close to each other, such that the material of the bottom substrate 3 and the material of the cover substrate 5 are seamlessly fused together, thereby hermetically sealing the functional region 13 or cavity 12 (located behind the laser welding line 8 in this view).

[0066] Figure 3 Details of the bonding area are shown, including the interface area, namely the contact area 25 and the laser welding area 8. The laser welding area 8 is disposed in the contact area 25 to bond the two substrates 3, 5 together.

[0067] Figure 4 It shows along Figure 1 The image shows a cross-sectional view of an embodiment of package 1 taken from line CD. Therefore, Figure 4 Cross-sections of functional regions 13, 13a are shown, which extend within the package 1, for example, in the form of a continuous hollow space or cavity. In other words, the cavity extends from the bottom substrate 3 into the cover substrate 5, and, for example, in the form of a groove formed in the bottom substrate 3 and / or the cover substrate 5. Here, functional region 13 is formed as a groove in the cover substrate 5, and functional region 13a is formed as a groove in the bottom substrate 3, for example, by a grinding process (e.g., sandblasting). In other words, the bottom substrate 3 has a groove 13a, and the cover substrate 5 has a groove 13 in which an article 2 is received.

[0068] For example, functional region 13a may also include an active layer, such as a conductive layer 34. The active layer of functional region 13a may also include a light receiver, for example, in the form of a photovoltaic cell, to be adapted to generate electrical energy. In this case, the package 1 may be a self-contained package 1. The functional region 13 disposed above the cover substrate 5 may include a cavity 12.

[0069] A laser welding zone 8, circumferentially arranged around functional regions 13, 13a, fully seals the functional regions 13, 13a along their sides. It is conceivable to leave gaps in the laser welding zone 8 so that functional regions 13, 13a are not fully sealed, for example, to maintain open communication channels or spaces for electrical connections, but these channels or spaces could also be used, for example, to establish fluid communication with the environment. In other words, it is conceivable not to use a focused laser beam 9 to seal predetermined locations or points, but to achieve hermetic sealing at those locations or points by other means (e.g., by adhesives). Preferably, functional regions 13, 13a are sealed along all their sides without any gaps, thereby ensuring hermetic sealing of functional regions 13, 13a. An article 2 (e.g., an electronic component) is arranged in a cavity 12 above the functional region 13a, i.e., for example, on the conductive layer 34.

[0070] refer to Figure 5 This shows another cross-sectional view of the package 1 taken along functional regions 13, 13a. The package 1 includes five substrate layers: a bottom substrate 3, three intermediate substrates 4a, 4b, and 4c, and a cover substrate 5. Intermediate substrates 4a and 4c each have a cavity 12 for accommodating components 2. Intermediate substrate 4b has an electrical via or glass channel 32 (referred to as a through-glass via (TGV)) that allows components in functional region 13 to be electrically connected to those components disposed in functional region 13a.

[0071] Functional region 13 is in the form of a cavity 12, in which multiple components 2 are arranged. Components 2 are sequentially disposed on a conductive layer 34, which is electrically connected to the glass through-hole 32. Therefore, the components 2 in functional region 13 are separated from the components 2 disposed in functional region 13a by an intermediate layer 4b. Now, for example, if a defect occurs in the component 2 disposed in functional region 13, or a liquid leak occurs, or overheating occurs, then the component 2 disposed in functional region 13a will be separated from it. In this way, possible defects in other components 2 due to the failure of the first component can be reduced or even prevented. To further improve the insulation effect, an insulating medium is included in both cavities 12.

[0072] refer to Figures 6a to 6e This illustrates an example for preparing the package 1 according to the invention. From Figure 6aInitially, a central intermediate substrate 4b is provided, which already has glass vias 32 or has glass vias 32 introduced into it. In this example, for economic reasons, the manufacturing process is performed by using a single wafer 4b to construct two packages 1. Subsequently, the two packages 1 can be separated along the separator line 10 using, for example, a laser cutting process. Alternatively, it is also conceivable to design a shared package having cavities 12 arranged adjacent to each other, corresponding to... Figure 6e The example in the figure shows the two parts without separating them along the dividing line 10. In this case, a horizontal glass through-hole 32 (not shown) can also be provided to connect adjacent cavities 12, the horizontal glass through-hole 32 being similar to the vertical glass through-hole 32 shown in the figure.

[0073] Figure 6b The diagram illustrates how an electrical contact layer 34 can be applied in some areas on either side of the central intermediate layer 4b. As shown, the electrical contact layer 34 is divided into multiple contact areas, and these contact areas can be electrically connected to one of the glass vias 32. If it is advantageous to do so, some contact areas 34 can also be applied without connecting to the glass vias 32, for example, to connect two components 2 within one cavity to each other, rather than to components 2 disposed in another cavity 12 within the package 1.

[0074] Figure 6c The illustration shows the housing 2 being mounted in a region corresponding to the subsequent cavity 12, for example, on the contact area 34. Using, for example, a glass through-hole 32, allows the component 2 to be electrically connected to other components 2 arranged in the same cavity 12 and / or other components 2 arranged in another cavity 12. The components 2 can be electrically connected, for example, by brazing, soldering, using epoxy conductive paste, or by wires.

[0075] Figure 6d The illustration shows the addition of spacer wafers 4a and 4c, one spacer wafer above the intermediate layer 4b and the other spacer wafer below the intermediate layer 4b. Spacer wafers 4a and 4c are laser-bonded to the intermediate layer 4b, i.e., laser bonding lines 8 are introduced respectively. Finally, Figure 6e The illustration shows a bottom substrate 3 added to the underside of the package 1 and a cover substrate 5 added to the topside of the package 1, and the substrates are then bonded together again by laser bonding lines 8.

[0076] Therefore, a laser welding area 8 is formed along the contact area 25 by laser pulse impact 16, wherein the cover substrate 5 is welded or bonded to the bottom substrate 3.

[0077] Figure 7An embodiment of a package 1 is shown, comprising a first intermediate glass layer 4a placed on a bottom substrate 3, a component carrier layer 4b on which a component 2 is placed, a further intermediate glass layer 4c, and a cover substrate 5. In this embodiment, functional regions 12, 13, 13a are arranged such that they are located below and above the component carrier layer 4b. Bonding lines 8 are provided around the cavity 12, such that the cavity 12 is hermetically sealed on all its sides. The package 1 can be circular or square, and in principle can have any free shape.

[0078] An article 2, such as a sensor or actuator, is disposed on the lower and upper sides of the component carrier layer 4b, for example, by bonding or welding to the component carrier layer 4b. A metal pad 34 for electrical contact with the article 2 is disposed on either side of the article 2. The article 2 is electrically connected to other components 2, for example, via a contact line 32 (e.g., a bonding line). The metal pad 34 can be a metal contact area. The substrates are directly bonded to each other via laser bonding lines 8. In this invention, two closed circumferential laser welding areas 8 are formed by guiding a laser 9 twice around the cavity along the contact area 25 (i.e., along the outer edge of the cavity 12), but these two closed circumferential laser welding areas 8 are not on exactly the same path. Instead, the laser 9 is guided along a laterally offset path for each revolution around the cavity 12, such that the two laser welding areas 8 are formed adjacent to each other. For example, the micro-welding area 8 in this example has a size of 5 μm × 10 μm or 10 μm × 50 μm.

[0079] Figure 8 An embodiment of package 1 is shown, wherein a cavity 12 is introduced into the intermediate substrate or component carrier layer 4b. The cavity 12 can be introduced into the intermediate substrate 4b by a sandblasting process, for example, the cavity 12 can more generally be recessed into the intermediate substrate 4b by a grinding process. Chemical etching is another option for introducing the cavity 12 into the intermediate substrate 4b. One advantage of this embodiment is that the cover substrate 5 can be made in the form of a simple glass plate, for example, which is bonded to the component carrier layer 4b by micro-welding and laser bonding lines 8. An advantage of this embodiment is that the component disposed in the upper cavity 12 (i.e., the cavity recessed in the intermediate substrate 4b) is configured to be protected by the intermediate substrate 4b during the manufacturing process. Furthermore, a substrate layer is omitted. In all embodiments of the figures, the same reference numerals denote the same components.

[0080] refer to Figure 9 This illustrates another embodiment of a method for producing a large quantity of package 1. Here, it will be explained, for example, as... Figure 8 The production of the package shown. It will be apparent to those skilled in the art that, depending on process requirements, only a single package 1 can be produced.

[0081] In step A, a shared component carrier substrate 4b is provided, having a plurality of grooves 12 corresponding to the subsequent cavity 12, and the plurality of grooves 12 are introduced into the component carrier substrate 4b by, for example, a grinding method. A corresponding receiving item 2 is placed in each groove 12, and the corresponding receiving item 2 is, for example, soldered to a contact 34 disposed there or already mounted there (see...). Figures 6a to 6e In step B, the shared cover substrate 5 is mounted on the component carrier substrate 4b, thus creating a separate cavity 12 for each recess. Multiple housing items 2 can be accommodated in a shared cavity 12.

[0082] Subsequently, it is anticipated that other components 2 will be mounted on the underside of the component carrier substrate 4b, forming other cavities 12, see [reference]. Figures 6c to 6e and Figure 8 Therefore, an additional intermediate glass layer 4a is arranged on the underside of the component carrier substrate 4b, and a bottom substrate 3 is arranged below the intermediate glass layer 4a. This is optional in terms of the manufacturing process of the present invention.

[0083] In step C, the processed substrate stacks are bonded together using a laser, thereby hermetically sealing each receiving cavity 12. This means that the cavity 12 is sealed along the entire circumference of the contact area 25, and each package 1 introduces at least one laser bonding line 8. For this purpose, a laser device 15 is guided from above the cover substrate 5 onto the surface of the cover substrate 5, and a focused laser beam 9 is selectively guided to the area to be bonded, i.e., to the contact area 25. Once step C of the manufacturing process is completed, all cavities 12 will be hermetically sealed. After step C, the individual packages 1 can be separated from each other by a cutting process to obtain individual packages 1.

[0084] In step D, the components are separated from each other along the dividing line or cutting line 10. Optionally, the same laser used for laser welding in step C can be used for this. Furthermore, conventional cutting techniques can also be employed if advantageous.

[0085] It will be apparent to those skilled in the art that the above embodiments are exemplary, and the invention is not limited thereto, but can be varied in many ways without departing from the scope of the claims. Furthermore, it is obvious that, whether or not disclosed in the specification, claims, drawings, or otherwise, the features individually define the essential components of the invention, even if they are described together with other features. In all the drawings, the same reference numerals denote the same components, thus a description of a feature that may be mentioned only in one drawing or at least not in conjunction with all the drawings can also be transferred to those drawings in which such feature is involved if it is not explicitly described in the specification.

[0086] List of reference numerals in the attached diagram:

[0087] 1. Hermetically sealed package

[0088] 2. To accommodate items and functional components

[0089] 3. Underlying substrate, layer, or wafer; bottom substrate or cover

[0090] 4, 4a, 4b, 4c, 4d, 4e, 4f Intermediate layers

[0091] 5. Top substrate, layer, or wafer; cover substrate or top cover.

[0092] 8 Laser welding area

[0093] 9. Focused laser beam

[0094] 10. Divider lines or cutting lines

[0095] 12. Accommodating cavity

[0096] 13 Functional Areas

[0097] 13a Second Functional Area

[0098] 14 Edge

[0099] 15 Laser devices for welding and / or cutting

[0100] 16 Laser pulse impact area

[0101] 18 Substrate stack

[0102] 21. Cavity edge

[0103] 22. Cavity bottom side

[0104] 23 Upper side of the cavity

[0105] 25 Contact Area

[0106] 32. Glass channel, glass through-hole

[0107] 34 Electrical contact layer

Claims

1. A hermetic sealing package (1) for a thermally sealed functional area, comprising: Bottom substrate (3); Cover substrate (5), the bottom substrate together with the cover substrate forms at least a portion of the package or forms the package; At least one intermediate substrate (4, 4a, 4b, 4c, 4d, 4e, 4f) is disposed between the bottom substrate (3) and the cover substrate (5). Multiple functional areas are hermetically sealed by the encapsulation (1), and the functional areas are in the form of cavities; At least one laser bonding line (8) that hermetically bonds the bottom substrate (3) and at least one intermediate substrate (4, 4a, 4b, 4c, 4d, 4e, 4f) and at least one laser bonding line (8) that hermetically bonds at least one intermediate substrate (4, 4a, 4b, 4c, 4d, 4e, 4f) and the cover substrate (5). Each of the laser bonding lines has a height (HL) perpendicular to its corresponding bonding surface. Among them, heat can be generated within the cavity of the package; Wherein, at least the bottom substrate and / or the cover substrate are in the form of thermal insulators; Wherein, the bottom substrate (3), the at least one intermediate substrate (4, 4a, 4b, 4c, 4d, 4e, 4f) and / or the cover substrate (5) comprise a glassy material; The encapsulation (1) contains a plurality of containers (2), and the containers (2) are distributed into different cavities; and The package (1) includes a glass through-hole located on an intermediate substrate (4, 4a, 4b, 4c, 4d, 4e, 4f) separating at least two cavities, which is used for electrically connecting the containment article (2) disposed in the different cavities.

2. The hermetic sealing package (1) according to claim 1. in, The bottom substrate (3), the at least one intermediate substrate (4, 4a, 4b, 4c, 4d, 4e, 4f), and / or the cover substrate (5) are made of a material with low thermal conductivity; and / or The bottom substrate (3), the at least one intermediate substrate (4, 4a, 4b, 4c, 4d, 4e, 4f) and the cover substrate (5) are in the form of thermal insulators.

3. The hermetic sealing package (1) according to claim 1. in, The bottom substrate (3), the at least one intermediate substrate (4, 4a, 4b, 4c, 4d, 4e, 4f) and / or the cover substrate (5) comprise glass, glass ceramic, silicon, sapphire or a combination of the above materials.

4. The hermetically sealed package (1) according to any one of claims 1 to 3, wherein, At least one of the laser bonding lines (8) circumferentially surrounds the cavity at a distance (DF) from the cavity.

5. The hermetic-sealed package (1) according to any one of claims 1 to 3. in, The contained article (2) includes electronic circuits, sensors or MEMS.

6. The hermetic-sealed package (1) according to any one of claims 1 to 3. in, The containing article (2) includes a power semiconductor chip; and / or The containing article (2) forms part of the package.

7. The hermetically sealed encapsulation component (1) according to claim 6, wherein, The power semiconductor chip is selected from the group consisting of: GaN LED, SiC power transistor, GaAs power transistor and GaN power transistor.

8. The hermetic-sealed package (1) according to any one of claims 1 to 3. in, The cavity includes an insulating medium to improve the insulation effect.

9. The hermetic sealing package (1) according to claim 8. in, The insulating medium is a fluid or a vacuum.

10. The hermetically sealed encapsulation component (1) according to claim 9. in, The fluid is an insulating liquid or an insulating gas.

11. The hermetically sealed package (1) according to any one of claims 1 to 3. It further includes at least one electrical connection layer on at least one of the at least one intermediate substrate (4, 4a, 4b, 4c, 4d, 4e, 4f).

12. The hermetically sealed package (1) according to any one of claims 1 to 3. in, At least one of the bottom substrate (3), the at least one intermediate substrate (4, 4a, 4b, 4c, 4d, 4e, 4f), and the cover substrate (5) is provided in the form of a multilayer composite, the multilayer composite including one or more coatings or prestressed areas, and / or including one or more substrates.

13. The hermetically sealed package (1) according to any one of claims 1 to 3. in, The laser bonding line (8) having the height (HL) extends into the material of the bottom substrate (3), the at least one intermediate substrate (4, 4a, 4b, 4c, 4d, 4e, 4f) and the cover substrate (5) disposed above the laser bonding line, and wherein the bottom substrate (3), the at least one intermediate substrate (4, 4a, 4b, 4c, 4d, 4e, 4f) and the cover substrate (5) are joined together by fusing with each other.

14. The hermetically sealed package (1) according to any one of claims 1 to 3, wherein, At least one of the bottom substrate (3), the at least one intermediate substrate (4, 4a, 4b, 4c, 4d, 4e, 4f), and the cover substrate (5) contains a mark.

15. The hermetic-sealed package (1) according to any one of claims 1 to 3. in, The package (1) is at least partially and / or a portion thereof transparent for a certain wavelength range.

16. The hermetic-sealed package (1) according to any one of claims 1 to 3. in, The cavity of the package is adapted to accommodate items with dimensions of 10mm × 10mm or smaller.

17. The hermetically sealed encapsulation component (1) according to claim 16. in, The cavity of the package is adapted to accommodate contents with a size of 5mm × 5mm or smaller.

18. The hermetically sealed package (1) according to claim 17. in, The cavity of the package is adapted to accommodate contents with dimensions of 2mm × 2mm or smaller.

19. The hermetically sealed package (1) according to claim 18. in, The cavity of the package is adapted to accommodate contents with a size of 1 mm × 1 mm or smaller.

20. A method for providing an hermetically sealed package (1), wherein, The encapsulation (1) encloses multiple functional areas, which are in the form of cavities. The method includes the following steps: - Provides a bottom substrate (3), at least one intermediate substrate (4, 4a, 4b, 4c, 4d, 4e, 4f) and a cover substrate (5), said cover substrate (5) being at least partially or a portion thereof transparent to at least one wavelength range; - Multiple containers (2) are arranged in the cavity, wherein the containers (2) are distributed to different cavities; - Above the containing article (2), the cover substrate (5) is arranged on the bottom substrate, thereby forming at least one contact area (25) between the at least one intermediate substrate (4, 4a, 4b, 4c, 4d, 4e, 4f) and the bottom substrate (3), and forming at least one contact area (25) between the at least one intermediate substrate (4, 4a, 4b, 4c, 4d, 4e, 4f) and the cover substrate (5), such that each package (1) has at least one contact area; - The cavity is hermetically sealed by forming at least one laser bonding line (8) along at least one contact area of ​​each package (1), wherein at least one laser bonding line (8) hermetically bonds the bottom substrate (3) and at least one intermediate substrate (4, 4a, 4b, 4c, 4d, 4e, 4f), and at least one laser bonding line (8) hermetically bonds at least one intermediate substrate (4, 4a, 4b, 4c, 4d, 4e, 4f) and the cover substrate (5). Wherein, at least one of the bottom substrate and the cover substrate is designed to be heat-insulating; Wherein, the bottom substrate (3), the at least one intermediate substrate (4, 4a, 4b, 4c, 4d, 4e, 4f) and / or the cover substrate (5) comprise a vitreous material; and The package (1) includes a glass through-hole located on at least one intermediate substrate (4, 4a, 4b, 4c, 4d, 4e, 4f) separating at least two cavities, which is used for electrically connecting the containment article (2) disposed in the different cavities.

21. The method according to claim 20, wherein, The method is used to form a package (1) according to any one of claims 1 to 19.

22. The method according to claim 20 or 21, wherein, A laser beam (9) is guided around the cavity to form the laser bonding line (8), thereby circumferentially sealing the cavity along the contact area (25).

23. The method according to claim 22, wherein, The laser beam is guided around the circumference multiple times, and / or multiple laser bonding lines are formed (8).

24. A package (1) produced by the method according to any one of claims 20 to 23, wherein an airtight accommodating cavity is enclosed.

25. The package (1) produced by the method according to any one of claims 20 to 23, wherein the containment cavity is hermetically sealed, is used as a medical implant or as a sensor.

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