MICROSCANNER SYSTEM AND METHOD AND SUBSTRATE STACK FOR ITS PRODUCTION

Abstract

A microscanner system for projecting electromagnetic radiation, in particular for imaging, onto an observation field, in particular into a solid angle extending from the microscanner system, has a substrate stack with a plurality of substrate layers stacked one on top of the other along a stack direction. In or on a first substrate layer of the substrate stack, a radiation source, in particular a laser radiation source with one or more lasers, for generating the electromagnetic radiation, in particular one or more laser beams, is arranged. A second substrate layer of the substrate stack has a micro-electro-mechanical system, MEMS, with at least one deflection element arranged in a beam path of the electromagnetic radiation and rotatably suspended about at least one axis of oscillation for variably deflecting at least one electromagnetic beam that can be emitted by the radiation source.The microscanner system is produced by singulation from a substrate stack, so that the manufacturing steps prior to singulation for a plurality of microscanner systems can be carried out at the level of the substrate stack, in particular wafer stacks.

Description

[0001] The present invention relates to a microscanner system for projecting electromagnetic radiation onto an observation field, in particular for imaging. It further relates to a method for producing a plurality of such microscanner systems and a substrate stack used as an intermediate product in the method.

[0002] Microscanners, which in technical jargon are also referred to as "MEMS scanners", "MEMS mirrors" or "micromirrors" or in English in particular as "microscanner" or "micro-scanning mirror" or "MEMS mirror", are micro-electromechanical systems (MEMS), more precisely micro-optoelectromechanical systems (MOEMS), from the class of micromirror actuators for the dynamic modulation of electromagnetic radiation, in particular visible light. Depending on the design, the modulating movement of an individual mirror can be translational or rotational about at least one axis. In the first case, a phase-shifting effect is achieved, in the second case a deflection of the incident electromagnetic radiation in a direction dependent on the current orientation of the mirror. In the following, microscanners are considered in which the modulating movement of an individual mirror is, at least partly, rotational.In contrast to mirror arrays, where the modulation of incident light is achieved through the interaction of several mirrors on a single MEMS component, the modulation in microscanners is typically generated via a single mirror per MEMS component (microscanner).

[0003] Microscanners can therefore be used in particular to deflect electromagnetic radiation in order to modulate the deflection direction of an incident electromagnetic beam, in particular a laser beam, using a deflection element (“mirror”). This can be used in particular to create a Lissajous projection of the beam into an observation field. This allows, for example, imaging or sensory tasks to be solved or display functionalities to be implemented. Furthermore, such microscanners can also be used to advantageously irradiate materials, in particular for their processing. Other possible applications include the lighting or illuminating of certain open or closed spaces or spatial areas with electromagnetic radiation, for example in the context of spotlight applications.

[0004] Microscanners often consist of a mirror plate (deflection plate) suspended laterally on elastically stretchable springs. A distinction is made between single-axis mirrors, which are preferably mounted so they can rotate around a single axis, and dual-axis and multi-axis mirrors, which allow rotations, particularly rotational oscillations, around a corresponding number of different axes (oscillation axes), especially simultaneously.

[0005] A microscanner system for deflecting an electromagnetic beam can thus, in particular, comprise a biaxial microscanner, i.e., a microscanner with two different non-parallel, in particular mutually orthogonal, oscillation axes. However, it is also possible for the microscanner system to comprise a combination of two or more individual microscanners, in particular single-axis microscanners, arranged such that the incident beam can be deflected successively by the various individual microscanners of the microscanner system in order to generate a two-dimensional deflection pattern, such as a raster scan or a Lissajous pattern. In a microscanner system with a combination of two or three single-axis microscanners, their non-parallel oscillation axes can, in particular, be orthogonal to one another in pairs.

[0006] In both imaging sensor technology and display functions, a multi-axis microscanner system is used to deflect electromagnetic radiation such as a laser beam or a shaped beam from any other source of electromagnetic radiation at least two-dimensionally, e.g., horizontally and vertically, in order to scan or illuminate an object surface within an observation field. In particular, this can be done by the scanned laser beam sweeping a rectangular area on a projection surface in the observation field. Thus, microscanner systems with at least a two-axis microscanner or with several, in particular two, single- or multi-axis microscanners connected in series in the optical path are used in these applications.

[0007] The wavelength range of the radiation to be deflected can, in principle, be selected from the entire spectrum, from short-wave UV radiation, through the VIS range, NIR range, IR range, FIR range, to long-wave terahertz and radar radiation. The radiation source for the electromagnetic radiation can, in particular, itself be an integral component of a microscanner system, as is the case with the present solution.

[0008] For a range of different microscanner applications, particularly for applications in the field of so-called "wearables", i.e. electronics worn on the body, very compact and cost-effective laser projectors are required. An important design for this purpose features one or more microscanners for beam deflection as well as one or more laser sources. Wearables can particularly include virtual reality (VR) glasses, augmented reality (AR) glasses, mixed reality (MR) glasses and other imaging devices worn on the body. The colors of the light generated by the light sources can, in the optical range of the spectrum, be primary colors of a color model for a color space and, for example, in the case of an RGB color model, be provided by three laser sources, one each for red, yellow and blue light.

[0009] In some known designs of microscanner systems, the differently colored laser components of a multicolor laser source (with several correspondingly differently colored individual lasers) are separated by color and hermetically encapsulated in their own TO packages. Since these packages are usually large and expensive, only a limited degree of miniaturization can be achieved.

[0010] In the conventional manufacturing of microscanner systems, all components of the microscanner system are individually assembled to form the microscanner system. This applies even to components such as integrated semiconductor circuits, which have previously been mass-processed and manufactured in parallel on semiconductor substrates. They are first separated into chips and then precision-assembled at the chip level on a common carrier component of the microscanner system. The components of the microscanner system, which can include a MEMS mirror, heat sinks, submounts, optics, and laser chips, must therefore all be individually mounted, aligned, mounted, contacted, and secured during the manufacturing of the microscanner system.

[0011] It is an object of the invention to provide a microscanner system which is improved, in particular with regard to its efficient manufacturability and / or miniaturization possibilities, and a method for its production.

[0012] This problem is solved according to the teaching of the independent claims. Various embodiments and further developments of the solution are the subject of the subclaims.

[0013] A first aspect of the solution presented here relates to a microscanner system for projecting, in particular for imaging, electromagnetic radiation into an observation field, in particular into a solid angle emanating from the microscanner system. The microscanner system comprises a substrate stack with a plurality of substrate layers stacked one on top of the other along a stacking direction. A radiation source, in particular a laser radiation source with one or more lasers for generating the electromagnetic radiation, for example one or more laser beams, in particular of different colors, is arranged in or on a first substrate layer of the substrate stack.A second substrate layer of the substrate stack has a micro-electro-mechanical system (MEMS) with at least one deflection element arranged in a beam path of the electromagnetic radiation and suspended so as to be capable of rotational vibration about at least one oscillation axis for deflecting at least one electromagnetic beam emitted by the radiation source in a directionally variable manner.

[0014] The term "substrate layer," as used herein, refers to a homogeneous or heterogeneous material layer. In a temperature range intended for use with the microscanner system, the material layer is typically a solid. It can, in particular, have a plate-like shape, at least in sections, and, depending on its function, can be made, in particular, from a semiconductor wafer or a material that is at least partially optically transparent in the wavelength range used by the microscanner system for projection, such as a glass wafer or an at least partially transparent plastic wafer.

[0015] The terms "comprises," "includes," "has," "includes," "has," "has," "having," or any other variation thereof, as used herein, are intended to cover non-exclusive inclusion. For example, a method or apparatus that includes or has a list of elements is not necessarily limited to those elements, but may include other elements not expressly listed or that are inherent in such a method or apparatus.

[0016] Furthermore, unless explicitly stated to the contrary, "or" refers to an inclusive "or" and not an exclusive "or." For example, a condition A or B is satisfied by one of the following conditions: A is true (or present) and B is false (or absent), A is false (or absent) and B is true (or present), and both A and B are true (or present).

[0017] As used herein, the terms "a" or "an" are defined to mean "one or more." The terms "another" and "another," and any other variations thereof, are defined to mean "at least one other."

[0018] The term “plurality”, as used herein, shall mean “two or more”.

[0019] The terms "first," "second," "third," and similar terms in the description and claims are used to distinguish between similar or otherwise similarly named elements and not necessarily to describe a sequential, spatial, or chronological order. It is understood that the terms so used are interchangeable under appropriate circumstances, and that the embodiments of the solution described herein may also operate in orders other than those described or illustrated herein.

[0020] The term “configured” or “set up” to perform a specific function (and respective variations thereof), as used here where appropriate, is to be understood as meaning that a relevant device or component thereof is already in a design or setting in which it can perform the function or is at least adjustable – i.e. configurable – so that it can perform the function after being set accordingly. The configuration can be carried out, for example, by appropriately setting parameters of a process sequence or of switches or the like for activating or deactivating functionalities or settings. In particular, the device can have a plurality of predetermined configurations or operating modes, so that configuration can be carried out by selecting one of these configurations or operating modes.

[0021] A microscanner system according to the first aspect can be advantageously manufactured within the framework of parallel processing, in particular due to its stack-like structure, in which a substrate stack is constructed from substrates corresponding to the substrate layers of the microscanner systems, so that a plurality of microscanner systems are formed simultaneously and arranged side by side by constructing a substrate stack and can be obtained from this by subsequent singulation. The microscanner systems can thus be manufactured, in particular, within the framework of parallel processing "at wafer level" (wafer-level processing), wherein the respective individual components of the microscanner systems, or at least a substantial part of them, are formed in the layer structure of the substrate stack, in particular as individual substrates or substrate layers thereof.This eliminates the need for individual housing of components prior to integration into the microscanner system, resulting in space savings and thus a particularly compact design and manufacturing efficiency (especially integration density). This also eliminates the need for individual housing of individual components of the microscanner system, such as laser sources.

[0022] Various exemplary embodiments of the microscanner system are described below, each of which, unless expressly excluded or technically impossible, can be combined with each other as well as with the other aspects of the present solution described below.

[0023] In some embodiments, the radiation source is configured to emit the electromagnetic radiation it generates at least predominantly as a focused beam with a beam direction deviating by an angle of no more than 10° from the stacking direction of the substrate stack. The beam direction can coincide, at least substantially, with the stacking direction, in particular deviate from it by no more than 1°. This allows for particularly compact designs, since the entire beam path within the respective microscanner systems runs through the stack structure. Thus, the stack structure can also be used for targeted beam guidance and beam shaping due to its design, in particular through the possible integration of optical elements.

[0024] In some embodiments, the substrate stack has at least one further substrate layer, in or on which a beam-shaping optic, in particular a diffractive or refractive one, is formed for beam shaping, which is configured to shape, in particular to collimate, the at least one electromagnetic beam before and / or after its deflection by the deflection element. The provision of one or more beam-shaping layers in the substrate stack makes it possible to implement any requirements regarding the beam profile of the electromagnetic radiation to be projected into the observation field by the microscanner system by the substrate stack itself, in particular by components belonging to it and thus to the microscanner system itself, so that external optics for this purpose can be dispensed with. This can also be used to reduce the overall space requirement and thus to miniaturize the projection solution as a whole.In addition, beam shaping can be carried out in close spatial proximity, i.e. at a short distance, from the radiation source, which can be used in particular to improve the optical properties of the microscanner system itself or the radiation it can project into the observation field.

[0025] In some embodiments, the substrate stack comprises, as each such further substrate layer, at least one third substrate layer with a first beam-shaping optics formed therein for beam shaping, wherein the first beam-shaping optics is configured to shape the at least one electromagnetic beam before it is deflected by the deflection element.

[0026] In some embodiments, the substrate stack comprises, as each such further substrate layer, in addition to or instead of the at least one third substrate layer, at least one fourth substrate layer with a second beam-shaping optics formed therein for beam shaping, wherein the second beam-shaping optics is configured to shape the at least one electromagnetic beam after its deflection by the deflection element.

[0027] In both cases, and in particular in the case of the combination of at least one third substrate layer with at least one fourth substrate layer, the beam shaping may in particular comprise a collimation of the (respective) beam.

[0028] In some embodiments, the beam-shaping optics or at least one of the beam-shaping optics comprises an axicon for at least partially beam-shaping the electromagnetic beam. The axicon can, in particular, be designed as a reflective axicon and arranged such that it directs the radiation generated by the radiation source onto the deflection element by means of reflection on the axicon, in particular onto a mirror surface of the deflection element, which is arranged on a side of the deflection element facing away from the radiation source (when the deflection element is in a non-deflected rest position). The deflection element can, in particular, have a central opening through which the beam emitted by the radiation source can at least partially reach the axicon to be reshaped there and directed onto the mirror surface of the deflection element. The beam reshaping can, in particular, comprise generating an annular beam cross-section.The use of an axicon can therefore be used on the one hand to generate a desired beam shape and / or on the other hand to achieve a particularly compact design, since the beam does not have to be guided laterally around the deflection element.

[0029] One or more of the beam-shaping optics can also be designed as collimators. The collimators can, in particular, be configured such that they collimate only along a single spatial dimension running perpendicular to the beam direction, i.e., for example, they transform a circular beam cross-section into a linear, in particular rectilinear, beam cross-section. This can be used, in particular, to achieve a corresponding collimation for each oscillation axis of the deflection element. In another variant, the collimators can be configured such that they transform a divergent elliptical beam into a collinear beam with a circular beam cross-section.

[0030] In some embodiments, the substrate stack has at least a fifth substrate layer, in or on which a driver circuit for electrically controlling the radiation source and / or a driver circuit for controlling a drive for a rotational oscillation movement of the deflection element about the at least one oscillation axis is formed. The or each fifth substrate layer can in particular be a semiconductor substrate, in or on which the driver circuit(s) is / are formed as an integrated circuit. The fifth substrate layer can in particular be interconnected to the first substrate layer and connected to it, directly or indirectly via a wiring level as a further substrate layer, so that the spatial distance between the radiation source and the driver circuit for its control and thus electrical resistances and / or electromagnetic interference (from outside or through induction or similar) is / are reduced.) can be kept very low.

[0031] In some embodiments, the first substrate layer is arranged between the fifth substrate layer and the second substrate layer, viewed along the stacking direction. Thus, in particular, the emission direction for the electromagnetic radiation can be defined as pointing away from both the first and the fifth substrate layer, so that the fifth substrate layer, which is usually opaque (particularly in the case of a semiconductor material), does not interfere with the beam path.

[0032] Specifically, in some variants of these embodiments, (i) the fifth substrate layer has the driver circuit for controlling a drive for the oscillating movement of the deflecting element; (ii) the second substrate layer has at least one actuator for driving the oscillating movement of the deflecting element; and (iii) the first substrate layer has an electrical line running through it for the direct or indirect electrical connection of the actuator to the driver circuit for controlling the drive. The line can in particular be designed as a so-called "via", for example as a through-silicon via (TSV) in the case of one or more silicon layers in the substrate stack or as a through-glass via (TGV) in the case of one or more glass layers in the layer stack. These variants also promote a compact design, particularly in the lateral direction (i.e., in the layer plane), since the line runs through the first substrate layer.

[0033] In some embodiments, the substrate stack has at least a sixth substrate layer, by means of which a first cavity formed in the substrate stack is hermetically sealed. Specifically, the deflection element or at least one of the deflection elements can be arranged in the hermetically sealed first cavity and suspended so as to be capable of rotational vibration about the at least one vibration axis. Thus, on the one hand, the deflection element is well protected against unwanted external influences, such as chemical or mechanical influences or interfering radiation, and on the other hand, this design also promotes a particularly compact design of the microscanner system. The cavity can, in particular, be evacuated and thus serve as a vacuum encapsulation in order to reduce or minimize, depending on the quality of the vacuum, air friction resistance that would otherwise occur during the vibrational movement, in particular even to at least substantially avoid it entirely.

[0034] In some embodiments, the radiation source is arranged at least partially within a second cavity formed in the first substrate layer. This allows the same or similar advantages to be achieved with respect to the radiation source as with respect to the deflection element in the first cavity.

[0035] Specifically, in some of these embodiments, a surface section of a side wall of the second cavity has at least one electrically conductive, in particular metallic, layer for establishing a respective electrical connection of the radiation source. This also allows for a particularly space-efficient electrical connection of the radiation source.

[0036] The term "electrical conductivity" (and variations thereof), as used herein, is a physical quantity that indicates the ability of a substance to conduct electrical current. "Electrically conductive" or "electrically conducting" is understood to mean an electrical conductivity that (at 25 °C) is at least 10 6 S / m.

[0037] In some embodiments, the first cavity and / or the second cavity contains a gas at a gas pressure below normal pressure, which gas consists at least predominantly of a protective gas. The first and / or second cavity can, in particular, be evacuated, ie, a gas with a gas pressure of 10 Pa (10 - 4bar) or less (every real vacuum is not completely free of matter). In the first cavity, this is particularly advantageous with regard to oscillation of the deflection element that is as free of gas friction and thus with low losses. In the second cavity, however, other advantages are more important, such as corrosion protection and protection against contamination of the radiation source. In particular, it is also possible for one of the two cavities to be evacuated (e.g. the first cavity), while the other cavity (e.g. the second cavity) is filled with a protective gas (particularly below normal pressure).

[0038] In some embodiments, the microscanner system further comprises: (i) a seventh layer arranged in the beam path of the radiation source and configured as a diffusing screen or ground glass such that, upon irradiation with the beam from the radiation source, an intermediate image is formed on the seventh layer; and (ii) projection optics for projecting the intermediate image into the observation field. The seventh layer can, in particular, be arranged downstream of the deflection element along the beam path, so that the intermediate image is generated on the seventh layer by the impingement of the beam previously deflected by the deflection element.The projection optics, which may in particular comprise a projection lens, are then arranged in such a way that they project the intermediate image created at the seventh layer in transmission or reflection, (i) directly or (ii) indirectly through one or more further layers of the substrate stack, into the observation field.

[0039] In some embodiments, the radiation source for at least partially generating the electromagnetic radiation comprises one or more of the following radiation emitters: edge-emitting laser, vertical cavity surface emitting laser (VCSEL), superluminescent diode (SLED), mini-LED, microLED. These radiation emitters can be applied or incorporated onto the first substrate layer, e.g., a silicon substrate or another mechanically suitable carrier substrate, in particular by a suitable transfer process.

[0040] In some embodiments, the deflection element has rotational symmetry with respect to an axis of symmetry running parallel to the stacking direction, and the radiation source is configured such that the electromagnetic beam generated during operation travels along the axis of symmetry of the deflection element and through an opening therein. Such a configuration can also be used to realize particularly compact designs, since beam deflection around the deflection element can be omitted. Furthermore, highly symmetrical designs can also be realized.

[0041] In some embodiments, one or more of the substrate layers, such as the first substrate layer and / or the second substrate layer, each have at least one alignment mark, by means of which at least two of the substrate layers of the microscanner system are aligned with one another in a dimension running transversely to the stacking direction. This allows the precision of the relative alignment of the various substrate layers to be increased, particularly with regard to achieving high-precision alignments in which optical disturbances (e.g., aberrations) caused by misalignments are reduced to at least negligible levels.

[0042] In some embodiments, one or more of the substrate layers, for example the first substrate layer and / or the second substrate layer, each have at least one alignment accuracy feature, based on which the accuracy of the relative alignment of at least two of the substrate layers of the microscanner system with respect to at least one spatial dimension (in particular orthogonally and / or along the stacking direction) can be determined. With the aid of the at least one alignment accuracy feature, the quality of the microscanner system or precursors thereof can be assessed, in particular before the substrate stack is separated into individual microscanner systems. This can in particular also be used to select out stacks or (after separation) microscanner systems that do not meet a predetermined quality criterion as evidenced by this assessment. In this way, production efficiency can be increased, since the selected substrate stacks orMicro scanner systems do not have to be further processed. This also ensures that products with misalignments are not delivered to market undetected. As a quality criterion (e.g. permissible tolerance range), a tolerance of a maximum of 5 µm, preferably a maximum of 1 µm, or even better a maximum of only 0.3 µm, has proven to be effective, particularly for lateral precision (i.e. across, in particular orthogonal, to the stacking direction). In tests, a spacing accuracy for the distance between successive substrate layers in the substrate stack of a maximum of 100 µm, preferably a maximum of 10 µm, particularly preferably a maximum of 1 µm, has proven to be a effective quality criterion.

[0043] In some embodiments, the microscanner system further comprises one or more cooling elements, each extending into or through at least two of the substrate layers and made of a material that has increased thermal conductivity compared to its respective immediate surroundings in the substrate stack. The cooling elements can, in particular, comprise metallic material fillings, depending on the type of substrate layers used, in so-called through-silicon vias (TSV) or through-glass vias (TGV) as heat sinks. This allows heat, in particular heat generated by the radiation source during its operation, to be effectively dissipated in the microscanner system along the heat transport paths defined by the cooling elements, without the need for cooling elements external to the stack.

[0044] A second aspect of the present solution relates to a substrate stack comprising a plurality of substrates stacked one upon another along a stacking direction, which are secured to one another at the respective interfaces of adjacent substrates by means of a respective bond, such as a wafer bond, an anode bond, or a eutectic bond, depending on the material of the substrates. A plurality of microscanner systems according to the first aspect, in particular of similar type, are configured adjacent to one another in the substrate stack in such a way that the microscanner systems can each be obtained from the substrate stack by separation, in particular sawing or laser cutting.In each of the microscanner systems, its respective substrate stack of substrate layers contains or is formed from an associated portion of the substrate stack, wherein the substrates of the substrate stack each form one of the substrate layers.

[0045] The term "substrate" as used herein, like the previously introduced term "substrate layer," refers to a homogeneous or heterogeneous material layer. In a temperature range intended for use with the microscanner system, the material layer is typically present as a solid. In particular, it can have a plate-like shape, at least in sections. The term "substrate" is used herein to designate a material layer that is simultaneously a proportional component of a plurality of the microscanner systems (in particular, all microscanner systems) in the substrate stack. In contrast, the term "substrate layer" is used to designate a material layer that, after being separated from the substrate stack, is only part of one of the microscanner systems. The separation can be carried out, in particular, using known separation methods for separating chips from semiconductor substrates, such as sawing.In particular, the separation can be carried out by separating the substrate stack along cutting lines that run transversely, in particular orthogonally, to the stacking direction.

[0046] The term "substrate" can refer in particular to a wafer, such as a wafer made of semiconductor material or a material that is at least partially transparent in a wavelength range used by the microscanner system for projection, such as a glass material or plastic. The shape of a main surface of the substrate, in particular the wafer, can in particular be circular (cf. Fig. 2) or rectangular, although other shapes are not excluded. In particular, the substrate stack can contain one or more semiconductor substrates as well as one or more glass substrates (the same applies to the substrate stack of the multi-beam microscanner systems with regard to its substrate layers). Furthermore, it is possible that, in addition to or instead of one or more glass substrates, a plastic substrate that is at least partially transparent in the relevant wavelength range is contained in the substrate stack. Such plastic substrates can in particular be designed as plastic optics wafers, i.e. contain one or more imaging optics. Such plastic substrates are generally cheaper to manufacture than glass substrates. They can advantageously be arranged in the substrate stack, in particular there.where no hermeticity requirements are met during the manufacturing process for the substrate stack and no subsequent high-temperature steps are required. Then, one or more plastic substrates with additional optical functions, such as relay optics or beam expansion optics, can be cost-effectively installed downstream of the MEMS in the beam path. Such downstream optics can be particularly useful if a specific augmented reality waveguide (e.g., a pair of spectacle lenses in a glasses application) requires a specific magnification of the beam cross-section to suppress parasitic artifacts that would otherwise occur.

[0047] A third aspect of the present solution relates to a method for producing a plurality of microscanner systems according to the first aspect, the method comprising: (i) stacking a plurality of substrates along a stacking direction to produce a substrate stack according to the second aspect, wherein adjacent substrates in the substrate stack are fastened to one another at their intermediate interface, in particular by means of a respective bond; and (iii) separating at least two of the microscanner systems from the substrate stack to obtain individual microscanner systems. In particular, to achieve particularly high manufacturing efficiency, 100 or more, in particular even 1,000, 10,000 or more microscanner systems can be separated from the substrate stack, for which purpose the substrate stack then contains at least this number of microscanner systems.

[0048] The substrate stack according to the second aspect can thus be regarded in particular as an intermediate product in the parallelized production of a plurality of microscanner systems according to the first aspect.

[0049] The term "stacking" of substrates refers to any form of creating a substrate stack of successive material layers along the stacking direction, with the material layers being referred to here as the substrate. This can therefore particularly involve stacking solid-state substrates, such as wafers. Depending on the material, layer deposition, for example, by liquid deposition followed by drying or curing, sputtering, or gas deposition processes (such as chemical vapor deposition, CVD), or mixed forms, are also conceivable.

[0050] In some embodiments of the method, stacking the substrates on top of one another comprises forming at least two partial substrate stacks by stacking two or more of the substrates on top of one another in each partial substrate stack. Adjacent substrates in each partial substrate stack are thereby fastened to one another at their intermediate interface, in particular by means of a respective bond connection (in particular by means of wafer bonding). The partial substrate stacks and optionally further substrates are then stacked on top of one another and fastened to one another at the interfaces, in particular again by means of a respective bond connection, in order to form the substrate stack as a whole. In this case, it is particularly possible to align the substrates and / or partial stacks to be joined together very precisely with one another in order to achieve an optimal fit. In this case, fitting accuracies in the sub-micrometer range are particularly advantageous and achievable.In addition, it is also possible to manufacture housings for microscanner systems on a stack basis, i.e., before singulation. This can be achieved, in particular, in a similar way to pure semiconductor wafers, using so-called wafer-level packaging (WLP).

[0051] One or more of the optionally present further substrates can be arranged in particular between the partial substrate stacks, so that the stacking of the partial substrate stacks can take place not only directly, but instead also indirectly, namely including one or more further substrates lying between the partial substrate stacks.

[0052] The formation of partial substrate stacks can be used particularly advantageously to implement process parallelization, in which two or more partial substrate stacks are produced simultaneously, thus enabling an increase in throughput. For example, different stacking stations can be used simultaneously in a production line to produce the various partial substrate stacks before these and, if necessary, the other substrates are assembled to form the entire substrate stack. This also makes it easy to implement manufacturing differences, such as different individual processes or process controls for the individual partial substrate stacks, without having to consider other partial substrate stacks or their production, for example with regard to usable processes or temperature or pressure ranges.

[0053] In some embodiments, an alignment mark is generated in or on at least one selected substrate layer, and at least one other substrate layer is aligned with respect to its position relative to the selected substrate layer(s) during formation of the substrate stack using the respective alignment mark. In particular, all substrate layers can be aligned using such alignment marks on one or more of the other substrate layers. This allows for highly precise alignment of the substrate layers with one another and thus, in particular, high optical quality of the microscanner systems.

[0054] In some embodiments, before singulation: (i) in or on the first substrate layer of the substrate stack, for each of the microscanner systems formed in the substrate stack, the radiation source associated with it, which has one or more radiation emitters, is formed in situ or mounted as a prefabricated component, in particular simultaneously (and thus highly efficiently) for all microscanner systems of the substrate stack. During the production of the substrate stack, the first substrate layer thus equipped with the radiation sources of the microscanner systems is then aligned as a whole relative to the second substrate layer, in particular using the alignment markings of the individual substrate layers involved in the alignment.

[0055] For this purpose, the adjustment may, in particular, comprise (i) activating the respective radiation sources of at least two microscanner systems that are not directly adjacent in the substrate stack and are preferably far apart from each other, and (ii) aligning the first substrate layer with at least one other of the substrate layers (or vice versa) based on a radiation pattern generated overall by the activated radiation sources. The further the activated radiation sources are from each other, the higher the achievable adjustment accuracy is generally.

[0056] In some embodiments, the method further comprises: (i) measuring a thickness of the produced substrate stack prior to singulation; (ii) comparing the measured thickness with a tolerance criterion defined for this purpose; (iii) if the measured thickness exceeds a value classified as tolerable by the tolerance criterion, selecting the substrate stack and omitting singulation; and (iv) otherwise performing singulation. This also allows the quality of the microscanner system or precursors thereof to be evaluated and used to increase the efficiency of the manufacturing process and for quality assurance.

[0057] The features and benefits explained with regard to the first aspect of the solution also apply to the other aspects of the solution.

[0058] Further advantages, features and possible applications of the present solution will become apparent from the following detailed description in conjunction with the figures.

[0059] It shows: Fig. 1 schematically shows a cross-sectional view through a microscanner system according to an exemplary embodiment; Fig. 2 schematically shows an exemplary embodiment of a substrate stack with a plurality of microscanner systems, e.g. according to Fig. 1; and Fig. 3 a flowchart illustrating an exemplary embodiment of a method for producing a plurality of microscanner systems, e.g. according to Fig. 1.

[0060] In the figures, like reference numerals designate like, similar, or corresponding elements. Elements shown in the figures are not necessarily drawn to scale. Rather, the various elements shown in the figures are depicted in such a way that their function and general purpose will be understood by those skilled in the art. Connections and couplings between functional units and elements shown in the figures may also be implemented as indirect connections or couplings, unless expressly stated otherwise.

[0061] Fig. 1 shows a microscanner system 100 according to an exemplary embodiment in a cross-sectional view along a Fig. 2 through a substrate stack 200.

[0062] The microscanner system 100 comprises a substrate stack consisting of a plurality of substrate layers 102 to 118 stacked one upon another along a stacking direction 101, each of which has an at least approximately or partially plate-like shape. Adjacent substrate layers are mechanically connected to one another. Depending on the material of the respective substrate layers to be connected, this can be achieved, in particular, by means of a known wafer bonding process, such as direct bonding, anodic bonding, eutectic bonding, glass frit bonding, or adhesive bonding.

[0063] A plate-shaped semiconductor substrate layer 102, in particular a semiconductor chip with at least one circuit integrated therein, serves as the base substrate of the substrate stack. In the present example, the semiconductor substrate layer 102 contains, on the one hand, a first driver circuit 102a for a drive device with at least one actuator (e.g., a piezo actuator) for driving an oscillatory movement of a deflection element 112a of the microscanner system 100, and a second driver circuit 102b configured as a driver circuit for a laser device 120 of the microscanner system 100 serving as a radiation source.

[0064] The laser device 120 can have one or more lasers, in particular laser diodes, as radiation emitters 120a. In the case of multiple radiation emitters, these can differ, in particular, with regard to the wavelengths of the laser radiation 130 they can emit. For example, three lasers can be provided that represent the primary colors of a color model of a color space, such as the primary colors red (R), green (G), and blue (B) of the RGB color model, so that a wide variety of colors from the color space can be represented by superimposing their laser radiation. The lasers can, in particular, be integrated into a common component that represents the laser device 120. In particular, such a laser device 120 can also be designed such that it effects beam combination (e.g., superimposition of the individual R, G, B beams at a point). For this purpose, the laser device 120 can, in particular, have optical guides 120b.The radiation emitters 120a and the optical conductors 120b (waveguides) can, in particular, also be integrated together (and possibly with additional components such as filters, e.g., tunable filters) in a photonic integrated circuit (PIC). The following types of radiation emitters are particularly suitable: edge-emitting lasers, surface-emitting lasers, superluminescent diodes, mini-LEDs, and micro-LEDs. The radiation emitters 120a of the laser device 120 can be selected to be the same or different in terms of their type. It is also conceivable that the aforementioned beam combining does not already occur in the laser device 120, but only in a subsequent region of the beam paths of the individual beams from the various radiation emitters.The substrate stack can accordingly be configured such that the beam paths of the various radiation emitters initially run separately before being combined in the region of one or more layers downstream of the laser device 120. For this purpose, a correspondingly configured optically active substrate layer can be provided, in particular.

[0065] In the substrate stack, substrate layer 102 is followed by a further substrate layer 104, wherein between the two layers there is a connection layer with electrical contacts 124a to 124c for electrically connecting terminals of driver circuits 102a and 102b to electrical lines 126 and 122, respectively, for connection to the drive device for deflection element 112a and to laser device 120, respectively. Laser device 120 is at least partially housed in a cavity 104a of substrate layer 104. Substrate layer 104 thus corresponds to the aforementioned "first" substrate layer.

[0066] The connection layer can be continuous, for example as a continuous wiring layer, or present in places, in particular in the form of only the electrical contacts 124a to 124c, which can be formed in particular by soldered connections or via eutectic bond connections. In particular, one or more of these connections can be specifically designed to act both as a mechanical connection (possibly with hermetic sealing) and as an electrical connection. In addition to the electrical contacts 124a to 124c, an electrically insulating material, in particular an underfill (so-called "underfill"; not shown), can also be present in order to strengthen the mechanical connection between the substrate layers 102 and 104, for example within the framework of a material-to-material connection (adhesive connection).In particular, the underfilling can also be designed to at least partially compensate for differences in thermal expansion coefficients between the two substrate layers 102 and 104 in order to increase the temperature resistance of the substrate stack and thus the reliability of the microscanner system 100.

[0067] In addition, one or more cooling elements 136 can be arranged in one or more substrate layers of the substrate stack, in particular in substrate layer 104, for cooling purposes. They can be configured, in particular, as channels filled with a highly thermally conductive material, in particular a metal, e.g., of the TSV or TGV type, so that they can act as a heat sink relative to their surroundings. Their path can, in particular, be aligned parallel to the stacking direction 101. In addition, they can be thermally connected to another, stronger heat sink, such as a heat sink (not shown), in order to better dissipate the heat they absorb.

[0068] In the further construction of the substrate stack, the substrate layer 104 is followed by a further substrate layer 106, which is formed from a material that is at least partially transparent in the wavelength range of the laser source 120 (in the case of multiple lasers, in their total used wavelength range), in particular from glass or a transparent plastic. The substrate layer 106 is configured to collimate electromagnetic radiation emitted by the laser source 120 by means of beam-shaping optics (e.g., by means of fast-axis collimation, FAC) or to focus it, in each case in particular in a radiation plane spanned by the stacking direction and a direction orthogonal thereto, in which a (first) oscillation axis of the deflection element 112a extends.In a microscanner system having two oscillation axes for the deflection element, the first oscillation axis can, in particular, be selected such that its associated natural and / or resonant frequency is greater than that of the other oscillation axis. The substrate layer 106 can, in particular, also be configured to form the above-mentioned optically effective substrate layer for beam combining.

[0069] After a further substrate layer 108, which serves as a spacer and has a central opening through which the beam path of the radiation 130 collimated by the substrate layer 106 passes, a further substrate layer 110 follows in the stack structure. Similar to the substrate layer 106, it is formed from a material that is at least partially transparent in the wavelength range of the laser source 120, in particular from glass or a transparent plastic. It serves to (further) collimate the radiation 130 by means of beam-shaping optics (e.g., by means of slow-axis collimation, SAC) or to focus it, in each case in a further radiation plane spanned by the stack direction and a direction orthogonal thereto, in which a second oscillation axis of the deflection element 112a runs, which oscillation axis is orthogonal to the first oscillation axis.By combining the two substrate layers 106 and 110, the radiation can be collimated across its entire cross-section, so that after passing through the substrate layer 110, it can be described as a parallel beam. The substrate layers 106 and 110 thus each correspond to an aforementioned "third" substrate layer. Optionally, however, a stacked structure is also possible in which the substrate layers 108 and 110 are omitted.

[0070] This is followed in the stack structure by a further substrate layer 112, in which a cavity 112b is formed centrally, in which the deflection element 112a is located. Fig. 1 in three different positions, with the middle position, represented by black bars, corresponding to a rest position of the deflection element 112a. The deflection element 112a has a ring shape, in particular that of a circular ring, so that it has a central opening 112d through which the radiation 130 coming from the substrate layer 110 can pass, as in Fig. 1. The substrate layer 112 thus corresponds to the aforementioned "second" substrate layer. The deflection element 112a can, in particular, have a rotational symmetry, such as a circular symmetry or an n-fold rotational symmetry, with respect to a symmetry axis 112c running parallel to the stacking direction 101.

[0071] In order to be able to generate a projection, in particular a multi-dimensional one, the deflection element 112a is attached to a frame-shaped section of the substrate layer 112 surrounding it via a suspension with one or more springs in such a way that it can simultaneously perform a rotational oscillation about each of the oscillation axes. The suspension can in particular be configured such that each of the rotational oscillations is harmonic in an angular range up to a maximum deflection angle when it occurs as a free oscillation, i.e. that the restoring force of the springs with respect to the respective oscillation axis obeys Hooke's law, at least to a good approximation. It is also conceivable that the suspension is configured such that the deflection element 112a and its suspension form a Duffing oscillator.

[0072] To drive the oscillations, a drive device (not shown) is provided on the deflection element 112a. It can, in particular, comprise one or more piezo actuators, which are mounted, for example, on one or more of the springs in order to deform them by applying force when appropriately controlled by the driver circuit 102a. This deformation can cause the deflection element 112a to deflect from its rest position in order to initiate and / or continuously continue a one- or multi-dimensional oscillation of the deflection element 112a. In the aforementioned case where the substrate layers 108 and 110 are omitted, the substrate layer 112 can follow the substrate layer 106 directly in the stack structure.

[0073] The drive device is connected to the driver circuit 102a via connecting lines guided through the underlying part of the substrate stack, of which Fig. 1, only one connecting line 126 is shown by way of example. Electrically conductive, in particular metallic, connecting bond connections 128 are provided at the interfaces between adjacent substrate layers of the part of the substrate stack through which the connecting lines extend in order to achieve good electrical conductivity along the or each line 126 as a whole.

[0074] For the connection bonds 128, metal-eutectic bonds, such as gold-tin bonds, or direct metal bonding processes, such as gold-gold bonds, are particularly suitable. For the vertical electrical line sections of the line(s) 126 in the substrate stack, electrically conductive vias are introduced into the respective substrate layers, for example, a so-called through-glass via (TGV) in the case of a glass substrate layer or a so-called through-silicon via (TSV) in the case of a silicon substrate layer. In addition to electrical conduction, the electrical lines 126, including the respective associated connection bonds 128, can also be used for thermal dissipation, which is particularly important for the substrate layer 104 with the typically heat-generating laser device 120.

[0075] The substrate layer 112 is followed by a further substrate layer 114, which, together with substrate layers 110 and 112, hermetically seals the cavity 112b with the deflection element 112a on all sides. Accordingly, the cavity 112b can be evacuated or at least filled with a gas under negative pressure, so that gas friction losses during the oscillation of the deflection element 112a can be (almost) completely avoided or at least significantly reduced. One or more, in particular all, further cavities that may be present in the substrate stack can also be hermetically sealed and evacuated or under negative pressure. This can apply in particular to a cavity between the two collimator substrate layers 106 and 110 and / or to the cavity 104a in the substrate layer 104 in which the laser device 120 is located.

[0076] In the stacked structure, the substrate layer 114 is followed by a further beam-shaping substrate layer 116, in which a transmitting axicon 116a is formed with a central reflection surface 116b applied thereon, acting as an additional reflective axicon. However, it is also conceivable for the substrate layers 114 and 116 to coincide, i.e., to form a single substrate layer structured to form the axicon.

[0077] In both cases, as in Fig. 1, there is a further substrate layer 118, which acts as a cover layer and simultaneously as a transmitting axicon or as a converging lens. The axicon 116a with the reflection surface 116b is arranged such that the radiation 130 emerging from the layer 114 during operation of the microscanner system 100 passes through the axicon 116a onto the reflection surface 116b, from where it is reflected onto the side of the deflection element 112a facing away from the laser device 120, on which side a mirror surface of the deflection element 112a is located. The radiation is reflected again at this mirror surface of the deflection element 112a in order to be projected through the substrate layer 114, the axicon 116a, a cavity between the substrate layers 116 and 118, and finally through the substrate layer 118 as a beam bundled by the latter into the observation field.

[0078] The substrate layers 114, 116, and 118 are therefore each formed, at least in the region of the beam path of the radiation 130, from a material that is at least partially transparent in the wavelength range of the laser source 120 (with the exception of the reflection surfaces 116a and 116b). The material can be glass or a transparent plastic, and the materials of the various substrate layers 114 to 118 mentioned can also be different from one another. The substrate layers 116 and 118 each correspond to an aforementioned "fourth" substrate layer.

[0079] Instead of the axicon, other beam shaping optics are also conceivable, such as a parabolic mirror or a planar deflection mirror.

[0080] The substrate layer 114 can also be designed in particular as a ground glass or diffusing glass, so that when irradiated with the rays deflected by the deflection element, an intermediate image is formed thereon, which is then projected into the observation field by the substrate layers 116 and 118, which act as projection optics.

[0081] The stack structure of the microscanner system 100 may further comprise rewirings (not shown) for electrical connections, wherein the rewirings may be formed in particular as rewiring levels at or near the interfaces between adjacent substrate layers, in particular in or on the substrate layers 102, 104 and / or 112.

[0082] In particular, several, in particular even all, substrate layers of the microscanner system can have a rotational symmetry with respect to the symmetry axis 112c, such as a circular symmetry or, in the case of a square floor plan, a fourfold rotational symmetry.

[0083] The further reference symbols WS1 to WS3 and 200 will be referred to below with reference to the Fig. 2 and Fig. 3 will be discussed.

[0084] Fig. 2 schematically illustrates an exemplary embodiment of a substrate stack 200, in particular wafer stacks, with a plurality of microscanner systems, e.g., microscanner systems 100 according to Fig. 1. The microscanner systems are formed laterally next to one another, similar to semiconductor chips on a semiconductor wafer. The stacked substrates of the substrate stack 200 form, in each case proportionally, the substrate layers of each of the substrate layers 102 to 118 formed in the substrate stack. Fig. The cross-section of the microscanner system 100 shown in Figure 1 can be obtained, for example, from the dashed line AA.

[0085] Fig. 3 shows a flowchart illustrating an exemplary embodiment 300 of a method for manufacturing a plurality of microscanner systems, e.g., microscanner systems 100 according to Fig. 1, to which reference is also made below.

[0086] In the method 300, a substrate stack 200 is first produced in processes 305 to 320 according to Fig. 2. In each of the processes 305 to 315, only a part of the substrate stack 200 is produced as a respective partial substrate stack WS1, WS2 or WS3 thereof as a precursor. These partial substrate stacks WS1, WS2 or WS3 are, together with the substrate stack 200, each proportionally for a single microscanner system 100 in Fig. 1. Each of the processes 305 to 320 can, for example, be executed in a dedicated production station or production line. In particular, the processes 315 and one or both of the processes 305 and 310 can be executed in a temporally overlapping manner, i.e., at least partially simultaneously. However, it is also conceivable to execute the processes sequentially, in particular using a single production line. The order of the processes 310 and 315 is freely selectable.

[0087] Specifically, in process 305, the partial substrate stack WS1 is created by bonding together substrates corresponding to the substrate layers 106 to 110. This can be done, in particular, in an evacuated or negatively pressurized chamber, so that later, in each of the resulting microscanner systems 100, a respective cavity hermetically enclosed by substrate layers 106 to 110 is evacuated or under negative pressure. If the substrates are not yet supplied in a finished state, the process 305 can also include the production of these substrates. The partial substrate stack WS1 forms a collimator or focusing optics for the radiation 130 for each microscanner system 100 to be formed in the substrate stack 200, as previously described with reference to Fig. 1 was explained in detail.

[0088] In process 310, the partial substrate stack WS1 is supplemented with the substrates corresponding to the substrate layers 112 with the deflection element 112a and the substrate layer 114 to form the partial substrate stack WS2. If or to the extent that these substrates are not yet supplied in a finished state, the process 310 may also include the production of these substrates.

[0089] In process 315, the partial substrate stack WS3 is produced, wherein, in particular, layer 104, which has already been structured as a precursor, is populated with the radiation source 120. In addition, substrates corresponding to the substrate layers 102 and 104, including the connection layer 124, are connected to one another. If or to the extent that these substrates are not yet supplied as precursors, process 315 can also include the production of these substrates (as precursors). The radiation source is contacted via the connection layer 124.

[0090] In process 320, to form the entire substrate stack 200, the previously produced partial stacks WS2 and WS3 are assembled and supplemented by substrates corresponding to the substrate layers 116 and 118. Depending on the type of substrates to be joined, the various wafer bonding methods already discussed above can be used to connect the adjacent substrates and subsequently also the partial substrate stacks WS1, WS2, or WS3, as well as the substrate stack 200 as a whole. Alignment markings 132 can be provided on one or more of the substrate layers for the relative alignment of the substrate layers to be joined of the respective partial stacks WS1 to WS3 to one another, and subsequently of the partial stacks WS2 and WS3 to one another, before or during the respective joining.In addition, to increase the accuracy of the alignment and / or for later evaluation of the substrate stack produced or of the microscanner system 100 separated therefrom, one or more alignment accuracy features 134, for example in scale form, can be formed or have been previously formed on relevant substrate layers, e.g., as illustrated on substrate layer 104.

[0091] The adjustment may instead or additionally comprise activating at least two microscanner systems that are not immediately adjacent in the substrate stack, wherein The first substrate layer and thus the radiation sources 120 are aligned with respect to at least one, in particular all, of the other substrate layers based on a radiation pattern generated overall by the activated radiation sources. This is an advantageous method for achieving particularly high alignment precision, particularly in connection with the mutual alignment of partial stacks WS1 to WS3.

[0092] Once the substrate stack is completed, it can be tested as a whole in a test process 325. For this purpose, its thickness, particularly its maximum thickness, is measured and compared with a previously defined tolerance criterion, such as a permissible tolerance range for the thickness. If the tolerance criterion is not met (330 - no), the substrate stack as a whole is rejected as defective (350).

[0093] Otherwise (330 - yes), the method continues with a test process 335, in which the microscanner systems 100 formed in the substrate stack are individually, but preferably simultaneously, tested at the level of the substrate stack (i.e., in the case of wafers, at the wafer level). If defects are detected in certain microscanner systems 100, these can be marked as faulty and / or classified as defective in associated data structures.

[0094] Then, in a singulation process 340, the finished substrate stack 200 is singulated into the individual, already tested, microscanner systems 100 contained therein. This can be done, in particular, using a sawing process. Such sawing processes, e.g., using diamond-coated saws, can in particular correspond to those known from semiconductor technology for singulating semiconductor wafers into individual chips.

[0095] Microscanner systems previously marked or classified as defective can then be individually selected, in particular rejected, in a subsequent selection process 345. LIST OF REFERENCE SYMBOLS 100 micro scanner system 101 Stacking direction 102 substrate layer with driver circuits 102a Driver circuit for driving the deflection element 102b Driver circuit for laser device 104 “first” substrate layer with laser device 104a Cavity for holding the laser device 106 Substrate layer with collimator for first oscillation axis 108 Substrate layer as spacer layer 110 Substrate layer with collimator for a second oscillation axis 112 “second” substrate layer with deflection element 112a Deflection element 112b Cavity for receiving the deflection element 112c axis of symmetry 112d Opening in the deflection element 114 Substrate layer as lid for the cavity with deflection element 116 Substrate layer with first and second axicon 118 Substrate layer with third axicon or convex lens 120 Radiation source, in particular laser device 120a Radiation emitters, in particular laser diodes 120b optical conductors 122 electrical cable for connecting the laser device 124a-c electrical contacts 126 electrical cable for connecting a drive device for the deflection element 128 electrically conductive connection bonds 130 electromagnetic radiation, in particular (laser) beams 132 adjustment marks 134 Adjustment accuracy feature 136 Cooling element 200 substrate stacks, especially wafer stacks 300 Manufacturing processes for microscanner systems with substrate stack as intermediate product 305-350 Processes within the framework of procedure 300

Claims

[1] Microscanner system (100) for projecting electromagnetic radiation (130) into an observation field, wherein: the microscanner system (100) comprises a substrate stack with a plurality of substrate layers stacked one on top of the other along a stacking direction (101); a radiation source (120) for generating the electromagnetic radiation (130) is arranged in or on a first substrate layer (104) of the substrate stack; a second substrate layer (112) of the substrate stack comprises a MEMS with at least one deflection element (112a) arranged in a beam path of the electromagnetic radiation (130) and suspended so as to be capable of rotational vibration about at least one vibration axis for deflecting at least one electromagnetic beam emittable by the radiation source (120) in a directionally variable manner. [2] Microscanner system (100) according to claim 1, wherein the radiation source (120) is configured to emit the electromagnetic radiation generated thereby at least predominantly as a focused beam with a beam direction deviating from the stacking direction (101) of the substrate stack at an angle of maximum 10°. [3] Microscanner system (100) according to one of the preceding claims, wherein the substrate stack has at least one further substrate layer (106; 110; 116; 118) in or on which a beam-shaping optic for beam shaping is formed, which is configured to shape the at least one electromagnetic beam (130) before and / or after its deflection by the deflection element (112a). [4] Microscanner system (100) according to claim 3, wherein the substrate stack comprises, as each such further substrate layer, at least one third substrate layer (106; 110) with a first beam-shaping optics formed therein for beam shaping, wherein the first beam-shaping optics is configured to shape the at least one electromagnetic beam (130) before it is deflected by the deflection element (112a). [5] Microscanner system (100) according to claim 3 or 4, wherein the substrate stack has, as each such further substrate layer, at least one fourth substrate layer (116; 118) with a second beam-shaping optic (116a, 118) formed therein for beam shaping, wherein the second beam-shaping optic (116a, 118) is configured to shape the at least one electromagnetic beam (130) after its deflection by the deflection element (112a). [6] Microscanner system (100) according to one of claims 3 to 5, wherein the beam-shaping optics or at least one of the beam-shaping optics has an axicon for at least partial beam-shaping of the electromagnetic beam. [7] Microscanner system (100) according to one of the preceding claims, wherein the substrate stack has at least one fifth substrate layer (102) in or on which a driver circuit (102b) for electrically controlling the radiation source (120) and / or a driver circuit (102a) for controlling a drive of a rotational oscillating movement of the deflection element (112a) about the at least one oscillation axis is formed. [8] Micro scanner system (100) according to claim 7, wherein, viewed along the stacking direction (101), the first substrate layer (104) is arranged lying between the fifth substrate layer (102) and the second substrate layer (112). [9] Microscanner system (100) according to claim 8, wherein: the fifth substrate layer (102) has the driver circuit (102a) for controlling a drive of the oscillating movement of the deflection element (112a); the second substrate layer (112) has at least one actuator for driving the oscillating movement of the deflection element (112a); and the first substrate layer (104) has an electrical line running through it for the direct or indirect electrical connection of the actuator to the driver circuit (102a) for controlling the drive. [10] Microscanner system (100) according to one of the preceding claims, wherein the substrate stack has at least one sixth substrate layer (114) by means of which a first cavity (112b) formed in the substrate stack is hermetically sealed. [11] Microscanner system (100) according to claim 10, wherein the deflection element (112a) or at least one of the deflection elements is arranged in the hermetically sealed first cavity (112b) and is suspended so as to be capable of rotational vibration about the at least one vibration axis. [12] Microscanner system (100) according to one of the preceding claims, wherein the radiation source (120) is arranged at least partially within a second cavity (104a) formed in the first substrate layer (104). [13] Microscanner system (100) according to claim 12, wherein a surface portion of a side wall of the second cavity (104a) has at least one electrically conductive layer for producing a respective electrical connection of the radiation source (120). [14] Microscanner system (100) according to one of claims 10 to 13, wherein the first cavity (112b) and / or the second cavity (104a) contains a gas at a gas pressure below normal pressure, which gas consists at least predominantly of a protective gas, or is evacuated. [15] Microscanner system (100) according to one of the preceding claims, further comprising: a seventh layer arranged in the beam path of the radiation source and designed as a diffusing screen or a focusing screen such that an intermediate image is formed on the seventh layer when it is irradiated with the beam of the radiation source; and a projection optics for projecting the intermediate image into the observation field. [16] Microscanner system (100) according to one of the preceding claims, wherein the radiation source (120) for at least partially generating the electromagnetic radiation (130) comprises one or more of the following radiation emitters: edge-emitting laser, surface-emitting laser, superluminescent diode, mini-LED, micro-LED. [17] Microscanner system (100) according to one of the preceding claims, wherein the deflection element (112a) has a rotational symmetry with respect to an axis of symmetry (112c) running parallel to the stacking direction (101) and the radiation source (120) is designed such that the electromagnetic beam (130) generated by it during its operation runs along the axis of symmetry (112c) of the deflection element (112a) and through an opening (112d) therein. [18] Microscanner system (100) according to one of the preceding claims, wherein one or more of the substrate layers each have at least one alignment mark (132) by means of which at least two of the substrate layers of the microscanner system (100) are aligned with one another in a dimension running transversely to the stacking direction (101). [19] Microscanner system (100) according to one of the preceding claims, wherein one or more of the substrate layers each have at least one alignment accuracy feature (134) by means of which the accuracy of the relative alignment of at least two of the substrate layers of the microscanner system (100) with respect to at least one spatial dimension can be determined. [20] Microscanner system (100) according to one of the preceding claims, further comprising one or more cooling elements (136) which each extend into or through at least two of the substrate layers and are formed from a material which has an increased thermal conductivity compared to its respective immediate surroundings in the substrate stack. [21] Substrate stack (200) with a plurality of substrates stacked on top of one another along a stacking direction (101), which substrates are fastened to one another at the respective interfaces of mutually adjacent substrates by means of a respective bond connection; wherein in the substrate stack (200) a plurality of microscanner systems (100) according to one of the preceding claims are formed adjacent to one another in such a way that the microscanner systems can each be obtained by singulation from the substrate stack (200); and wherein in each of the microscanner systems (100) its respective substrate stack of substrate layers contains an associated portion of the substrate stack (200), wherein the substrates of the substrate stack (200) each form one of the substrate layers. [22] A method (300) for manufacturing a plurality of microscanner systems (100) according to any one of claims 1 to 19, the method (300) comprising: Stacking (305, ..., 320) a plurality of substrates along a stacking direction (101) to produce a substrate stack (200) according to claim 20, wherein adjacent substrates in the substrate stack (200) are fastened to one another at their interface therebetween; and Separating (330) at least two of the microscanner systems from the substrate stack. [23] Method (300) according to claim 21, wherein the stacking (305, ...,320) comprises: Forming at least two partial substrate stacks (WS1, ..., WS3) by stacking two or more of the substrates per partial substrate stack (WS1, ..., WS3) on top of each other, wherein adjacent substrates in each partial substrate stack (200) are fastened to each other at their intermediate interface by means of a respective bond connection; and Stacking and fastening the partial substrate stacks (WS1, ...,WS3) and optionally further substrates to one another in order to form the substrate stack (200) as a whole. [24] Method (300) according to claim 22 or 23, wherein an alignment mark (132) is produced in or on at least one selected substrate layer (104) and at least one other substrate layer (106) is adjusted with respect to its relative position to the selected substrate layer(s) (104) by means of the respective alignment mark (132) during formation of the substrate stack. [25] Method (300) according to one of claims 22 to 24, wherein before singulating (340): in or on the first substrate layer of the substrate stack (200), for each of the microscanner systems (100) formed in the substrate stack (200), the radiation source (120) associated with it, which has one or more radiation emitters (120a), is formed in situ or mounted as a prefabricated component; and during the production of the substrate stack, the first substrate layer (104) equipped with the radiation sources (120) of the microscanner systems (100) is adjusted as a whole relative to the second substrate layer (112). [26] The method (300) of claim 25, wherein the adjusting comprises: Activating the respective radiation sources of at least two microscanner systems that are not directly adjacent in the substrate stack; and Aligning the first substrate layer with at least one other of the substrate layers based on a radiation pattern generated overall by the activated radiation sources. [27] Method (300) according to one of claims 22 to 26, further comprising: Measuring (325) a thickness of the produced substrate stack before singulation; comparing (330) the measured thickness with a tolerance criterion defined in this regard; if the measured thickness has a value beyond a value classified as tolerable by the tolerance criterion, selecting (350) the substrate stack without separating (340); and otherwise, carry out the separation (340).

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