DE102019213284A1 - Interferometer device and method for manufacturing an interferometer device - Google Patents

Abstract

The present invention creates an interferometer device (10) comprising a Fabry-Perot interferometer (1), which comprises at least two mutually spaced mirror devices (SP1; SP2) and a substrate (2), the mirror devices (SP1; SP2) each parallel across the substrate (2) are arranged and at least one of the mirror devices (SP1; SP2) is movable with respect to the substrate (2); a base substrate (3) which comprises a cavity (4) and at least one electrical conductor track (5), the Fabry-Perot interferometer (1) being arranged on the base substrate (3) and covering the cavity (4); and at least one detector device (6) which is arranged in the cavity (4) and is electrically contacted by means of the electrical conductor track (5).

Description

The present invention relates to an interferometer device and a method for producing an interferometer device.

State of the art

Miniaturized spectrometers with Fabry-Perot interferometers (FPI) usually include spacers in order to be able to arrange an FPI above a detector and to be able to make electrical contact with the detector below the FPI, which, however, can lead to a relatively large overall height in relation to a printed circuit board surface. This can lead to an increased assembly tolerance and require additional steps during assembly and increase the material costs. Such spacers can include additional openings through which unfiltered light can be scattered past the FPI onto the detector, which can influence a signal-to-noise ratio.

In the EP 3 064 912 A1 a light detector is described which includes a wiring substrate, a Fabry-Perot interferometer, and spacers between the Fabry-Perot interferometer and the wiring substrate to form a cavity for a photodetector.

Disclosure of the invention

The present invention provides an interferometer device according to claim 1 and a method for manufacturing an interferometer device according to claim 13.

Preferred further developments are the subject of the subclaims.

Advantages of the invention

The idea on which the present invention is based consists in specifying an interferometer device which is characterized by an improved possibility of contacting the interferometer and detector elements, is advantageously space-saving and can be manufactured inexpensively with a few components and a few manufacturing steps. A small-scale component, in particular a filter element and / or spectrometer, with a low overall height and a detector device shielded from scattered light can be achieved by means of fewer components.

According to the invention, the interferometer device comprises a Fabry-Perot interferometer, which comprises at least two mutually spaced mirror devices and a substrate, the mirror devices each being arranged in parallel above the substrate and at least one of the mirror devices being movable with respect to the substrate; a base substrate which comprises a cavity and at least one electrical conductor track, wherein the Fabry-Perot interferometer is arranged on the base substrate and covers the cavity; and at least one detector device which is arranged in the cavity and is electrically contacted by means of the electrical conductor track.

The mirror devices can each comprise at least one high refractive index layer or a low refractive index layer between two high refractive index layers, it being possible for this arrangement to be transparent to a specific wavelength. Depending on the distance between the two mirror devices, a corresponding wavelength of external light can be transmitted into the cavity and hit the detector device (s). At least one of the mirror devices can be moved, for example, by an actuator, advantageously essentially parallel to the respective other mirror device.

The base substrate can be produced as a printed circuit board (PCB), advantageously as a wiring substrate. The cavity in the base substrate can be formed by a recess in the base substrate and advantageously only partially penetrates it. The detector device can advantageously be arranged partially or completely sunk in the cavity.

With the interferometer device according to the invention, the most cost-effective, yet powerful spectrometer with the lowest possible number of components and a minimum number of simple / inexpensive manufacturing steps and the smallest possible size can be achieved, which is still achieved by a reduced or completely suppressed incidence of unfiltered scattered light can distinguish on the detector. Conventional structures according to the prior art either require a large number of (expensive) components or (expensive) process steps or require large construction volumes or do not completely shield stray light. The interferometer device can be produced as a small-scale, compact (package) detector arrangement with a few components.

As a result of the direct arrangement of the Fabry-Perot interferometer on the base substrate, the overall height of the interferometer device can advantageously be reduced and separate spacers can be dispensed with, since the electrical wiring can also be carried out via the base substrate, for example with a conductive adhesive and / or with Bond wires.

According to a preferred embodiment of the interferometer device, the Fabry-Perot interferometer comprises an optical area which is suitable for filtering and transmitting a light and wherein the optical area is arranged above the cavity.

According to a preferred embodiment of the interferometer device, the at least one electrical conductor track is at least partially embedded in the base substrate and extends into the cavity.

According to a preferred embodiment of the interferometer device, the at least one electrical conductor track is arranged on an upper side of the base substrate facing the Fabry-Perot interferometer, and electrical contact of the detector device is established with the electrical conductor track via a contact wire.

According to a preferred embodiment of the interferometer device, the substrate comprises a recess above the cavity, which protrudes laterally beyond the cavity.

According to a preferred embodiment of the interferometer device, it comprises at least a first detector device and a second detector device, which are sensitive to different wavelength ranges and are arranged one above the other or next to one another in the cavity.

According to a preferred embodiment of the interferometer device, the cavity comprises a first cavity and a second cavity formed therein, which has a laterally smaller extent than the first cavity, and wherein the first and / or the second detector device is arranged in the second cavity.

According to a preferred embodiment of the interferometer device, the second detector device is arranged in the second cavity and the first detector device is arranged in the first cavity, and at least partially spans the second cavity.

According to a preferred embodiment of the interferometer device, an optical element, for example an edge filter, is arranged in the first cavity and arranged above the first and / or second detector device.

According to a preferred embodiment of the interferometer device, the first detector device is sensitive to smaller wavelengths than the second detector device.

According to a preferred embodiment of the interferometer device, the cavity is at least partially covered with a reflective layer.

According to a preferred embodiment of the interferometer device, the base substrate comprises at least one heat sink which is in thermal contact with the detector device and / or with the Fabry-Perot interferometer.

According to the invention, in the method for producing an interferometer device, a base substrate with a cavity and at least one electrical conductor track is provided; arranging at least one detector device in the cavity and electrically contacting the detector device with the electrical conductor track; and arranging a Fabry-Perot interferometer which comprises at least two mirror devices which are spaced apart from one another and a substrate, the mirror devices each being arranged in parallel above the substrate and at least one of the mirror devices being movable with respect to the substrate.

The method can advantageously also be distinguished by the features already mentioned in connection with the interferometer device and their advantages, and vice versa.

According to a preferred embodiment of the method, the detector device is contacted with a contact wire.

Further features and advantages of embodiments of the invention emerge from the following description with reference to the accompanying drawings.

Figure list

The present invention is explained in more detail below with reference to the exemplary embodiments specified in the schematic figures of the drawing.

• 1 eine schematische Seitenansicht der Interferometereinrichtung gemäß eines Ausführungsbeispiels der vorliegenden Erfindung;
• 2 eine schematische Draufsicht auf eine Interferometereinrichtung gemäß eines Ausführungsbeispiels der vorliegenden Erfindung;
• 3 eine schematische Seitenansicht der Interferometereinrichtung gemäß eines weiteren Ausführungsbeispiels der vorliegenden Erfindung;
• 4 eine schematische Seitenansicht der Interferometereinrichtung gemäß eines weiteren Ausführungsbeispiels der vorliegenden Erfindung;
• 5 eine schematische Seitenansicht der Interferometereinrichtung gemäß eines weiteren Ausführungsbeispiels der vorliegenden Erfindung; und
• 6 ein schematisches Blockschaltbild von Verfahrensschritten eines Verfahrens gemäß eines Ausführungsbeispiels der vorliegenden Erfindung.

Show it:

• 1 a schematic side view of the interferometer device according to an embodiment of the present invention;
• 2 a schematic plan view of an interferometer device according to an embodiment of the present invention;
• 3rd a schematic side view of the interferometer device according to a further embodiment of the present invention;
• 4th a schematic side view of the interferometer device according to a further embodiment of the present invention;
• 5 a schematic side view of the interferometer device according to a further embodiment of the present invention; and
• 6th a schematic block diagram of method steps of a method according to an embodiment of the present invention.

In the figures, identical reference symbols denote identical or functionally identical elements.

1 shows a schematic side view of the interferometer device according to an embodiment of the present invention.

The interferometer device 10 includes a Fabry-Perot interferometer 1 , which has at least two mutually spaced mirror devices SP1 and SP2 and a substrate 2 may include, wherein the mirror devices SP1 and SP2 each parallel over the substrate 2 are arranged and at least one of the mirror devices with respect to the substrate 2 is movable. The interferometer device also includes 10 a base substrate 3rd , which is a cavity 4th and at least one electrical conductor track 5 comprises, wherein the Fabry-Perot interferometer 1 on the base substrate 3rd is arranged and the cavity 4th covered. The interferometer device 10 comprises at least one detector device 6th which in the cavity 4th is arranged and by means of the electrical conductor track 5 is electrically contacted. The detector device 6th can in the cavity 4th be partially or completely sunk in their height. The substrate 2 can even over the cavity 4th a recess A. include, which is the cavity 4th can protrude laterally.

On a top O1 of the base substrate 3rd can the conductor track 5 be arranged and the Fabry-Perot interferometer 1 can on the base substrate 3rd and / or at least partially on the conductor track 5 by means of a connection 11 be arranged and attached. The connection 11 can be an adhesive connection, a soldering connection, a bond connection or another and the substrate 2 on the base substrate 3rd fix. The connection 11 can advantageously be electrically insulating. On the base substrate 3rd can also be a contact point 5a be arranged, which with an outer contact wire 7a can be connected, the outer contact wire 7a to a contact point T on the Fabry-Perot interferometer 1 , advantageously on the base substrate 3rd facing away from the top, can be arranged. The contacting of the Fabry-Perot interferometer 1 can for example serve to actuate the mirror devices. The point of contact T can be beneficial over the connection 11 be arranged, whereby an improved quality of the contact wires can be achieved.

The base substrate can be designed as a printed circuit board, LTCC ceramic substrate (multilayer ceramic) or as a premold housing (prefabricated by injection molding).

The Fabry-Perot interferometer 1 can have an optical area in the lateral inner area IF form, which can be suitable for the transmission of a light (depending on the mirror spacing filtered external light), the optical range IF above the cavity 4th can be arranged.

From the track 5 can be an electrical contact of the detector device 6th with the electrical conductor track 5 via a contact wire 7th be made, which in the cavity 4th and possibly also into the recess A. (vertically) can reach into it. The detector device 6th can advantageously have a contact area on the base substrate for contacting 3rd embrace away from the side. Due to the recessed arrangement, contact can be made via the contact wire 7th be made possible and still be formed, in particular in height, a small-scale component. In addition, the Fabry-Perot interferometer 1 better be arranged on an optical axis above the detector device without significantly changing the height of the component.

The cavity 4th can at least partially with a reflective layer 8th be covered, which the bottom and / or the side walls of the cavity 4th can partially or completely cover. In this way, the Fabry-Perot interferometer can do this 1 transmitted light are better concentrated within the cavity, an absorption by the base substrate 3rd be reduced or avoided within the cavity and the filtered light is better concentrated on the detector device and absorbed there. The reflective layer 8th can be formed from a metallization, for example from the electrical conductor track 5 (double function of contacting and reflection possible).

The Fabry-Perot interferometer 1 can advantageously only in regions or on one side on the base substrate 3rd with the connection 11 be fixed. Therefore, at least one area can have a mounting area on the base substrate 3rd be available on which to connect 11 can be dispensed with.

By covering the cavity 4th by the Fabry-Perot interferometer 1 it can be beneficial prevented or reduced that unfiltered scattered light from the environment can hit the detector device. By reducing or avoiding the impact of unfiltered scattered radiation on the detector device, a signal-to-noise ratio of the interferometer device can be improved.

The interferometer device can be designed as a micromechanical component, advantageously as a microspectrometer, with the Fabry-Perot interferometer as well 1 can be formed as a micromechanical component and can act as a filter that can be tuned in terms of wavelengths. The interferometer device can also be designed as a module for integration in larger assemblies.

Through the recess A. wavelengths can also be transmitted through the FPI, which would otherwise be absorbed in the substrate material. When the cavity is covered 4th The contact wire can laterally beyond this 7th i.e. directly on the surface of the base substrate 3rd are drawn, an otherwise necessary via (via) in or through the base substrate 3rd can be omitted.

The connection 11 can the electrical conductor path 5 cover advantageously at least partially or completely.

The contact wire 7th can be placed in the cavity to save space 4th be guided. Thus, an electrical connection to the detector device 6a within the optical range IF respectively.

2 shows a schematic plan view of an interferometer device according to an embodiment of the present invention.

In the 2 the interferometer device from the 1 in plan view, in particular along a direction of incidence of light on the Fabry-Perot interferometer 1 shown. The optical area IF can be shaped as a circular area, as can the cavity 4th and the recess A. in the substrate 2 . The 2 shows only a circular optical area in this regard IF For the sake of clarity, the shape of the cavity has been shown 4th and the recess A. waived. The shape of the cavity 4th and / or the recess A. and / or the optical area IF can also deviate from a circular shape. The electrical conductor path 5 can from an edge area above the base substrate 3rd up to the optical area IF are led into it, advantageously as a narrow conductor track (e.g. metallization on the base substrate 3rd ) and can have a contact area below the recess A. for the contact wire 7th train, by means of which the detector device 6th can be contacted. The connection 11 can be in an edge area, for example only on one side of the base substrate 3rd , be attached, advantageously below the contact points T which may comprise a plurality and on the Fabry-Perot interferometer 1 can be arranged. The connection 11 can the recess A. preferably only partially laterally, ie not completely, enclose it laterally. In this way, the coupling of mechanical stress from the structure into the interferometer device can be reduced. The connection 11 can preferably be on a lower edge of the Fabry-Perot interferometer 1 be reduced while at least one side has a mechanical assembly stop without the connection 11 may have. The Fabry-Perot interferometer can only be placed in this assembly stop.

On the base substrate 3rd can also have one or more contact points 5a be arranged, which with outer contact wires for contacting the Fabry-Perot interferometer 1 can be connected.

3rd shows a schematic side view of the interferometer device according to a further embodiment of the present invention.

The embodiment of the 3rd differs in this from that of the 1 that the Fabry-Perot interferometer 1 a completely continuous substrate 2 may include, in other words, the recess in the substrate 2 be waived if this is to be expected by the Fabry-Perot interferometer 1 filtered radiation is transmissive.

The cavity in the base substrate 3rd can be formed large enough so that at least one first detector device 6a and a second detector means 6b in the cavity 4th can be arranged, which can be sensitive to different wavelength ranges, and in the cavity 4th can be arranged one above the other. The two or more detector devices can also be stacked next to one another or at least partially.

The at least one electrical conductor track 5 can in the base substrate 3rd be at least partially embedded and extend into the cavity 4th extend into it. A contact wire can then be placed in the cavity 7th from the electrical conductor track 5 to the first detector device 6a and to the second detector device 6b be guided. The electrical conductor path 5 can be used for external contact through the base substrate 3rd extend therethrough, for example to a top O1 of the base substrate on which the Fabry-Perot interferometer 1 can be arranged and advantageously laterally outside an area on which the Fabry-Perot interferometer 1 can be arranged a first Contact area 5 ' form. The electrical conductor path 5 can have at least one via 5b include, which extends through the base substrate 3rd can extend, advantageously between a first contact area 5 ' the conductor track 5 and a second contact area 5 " , which in the base substrate 3rd can be embedded and extend into the cavity 4th can extend into it.

The base substrate 3rd can at least have a heat sink 9 include, which with the detector device and / or with the Fabry-Perot interferometer 1 can be in thermal contact. The at least one heat sink 9 can on one of the top O1 opposite back O2 be arranged, or in the base substrate 3rd be at least partially embedded. From the heat sink 9 which, for example, below the cavity 4th can be arranged, can extend through the base substrate 3rd continuous connectors 9b to the first or second detector device 6a or 6b (up to the cavity 4th into). The heat sink can also comprise a further area or a further separate heat sink 9 below the connection 11 be arranged and there can be more connectors 9b through the base substrate 3rd until the connection 11 Extend (up to the glue). In this way, heat can be removed from the detector devices and / or from the Fabry-Perot interferometer 1 be discharged. The heat can be transmitted from and in the detector device or the connection 11 absorbed radiation result. The connectors 9b and / or the heat sink 9 can comprise a metal.

4th shows a schematic side view of the interferometer device according to a further embodiment of the present invention.

The embodiment of the 4th differs in this from that of the 3rd that the cavity 4th a first cavity 4a and a second cavity formed therein 4b comprises, which comprises a laterally smaller extent than the first cavity 4a , and wherein the second detector means 6b in the second cavity 4b can be arranged and the first detector device 6a in the first cavity 4a can be arranged. The first detector device 6a can the second cavity 4b at least partially span, advantageously completely. At least one of the cavities 4a and 4b can with a reflective layer 8th be covered, at least on their floor.

The at least one electrical conductor track 5 can be similar to the 3rd in the base substrate 3rd be at least partially embedded and extend into the cavities 4a and 4b extend into it, advantageously at different levels, so that the bottom of the respective cavity is always 4a or 4b is achieved. A contact wire can then be placed in the cavity 7th from the electrical conductor track 5 to the respective detector device arranged in this cavity 6a or 6b be guided. The electrical conductor path 5 can be used for external contact through the base substrate 3rd extend therethrough, for example to a top O1 of the base substrate on which the Fabry-Perot interferometer 1 (FPI) can be arranged, and advantageously laterally outside an area on which the Fabry-Perot interferometer 1 can be arranged, several first contact areas 5 ' form. The electrical conductor path 5 can for each level of the corresponding cavity 4a and 4b at least one via 5b include, which extends through the base substrate 3rd can extend, advantageously between a first contact area 5 ' the conductor track 5 and a second contact area 5 " , which in the base substrate 3rd can be embedded.

As in the upper left area of the 4th can be shown after execution V1 in plan view, the first and second cavities can be formed concentrically and with parallel side flanks or according to execution V2 have side flanks rotated by an angle.

The two detector devices 6a and 6b can in the stepped pyramid-shaped cavities 4a and 4b be arranged so that the first detector device 6a for shorter wavelengths on a step closest to the FPI and the second detector device 6b for longer wavelengths can be mounted on a subordinate paragraph. Due to a different sensitivity for the transmitted wavelengths, an order separation can be achieved in the identification of the radiation transmitted by the Fabry-Perot interferometer.

5 shows a schematic side view of the interferometer device according to a further embodiment of the present invention.

The embodiment of the 5 differs in this from that of the 3rd that the cavity 4th a first cavity 4a and a second cavity formed therein 4b comprises, which can comprise a laterally smaller extent than the first cavity 4a , and wherein in the first cavity an optical element 12th above the first and / or second detector device 6a or 6b can be arranged. The optical element 12th can the second cavity 4b cover completely advantageously. The optical element 12th can comprise an edge filter, an element restricting the angle of incidence, an aperture stop and / or further optical elements. The detector device 6a can via the contact wire 7th space-saving within the cavity 4th be connected electrically.

6th shows a schematic block diagram of method steps of a method according to of an embodiment of the present invention.

In the method for producing an interferometer device, provision takes place S1 a base substrate with a cavity and at least one electrical conductor track; an arranging S2 at least one detector device in the cavity and an electrical contact S3 the detector device with the electrical conductor track; and arranging S4 a Fabry-Perot interferometer which comprises at least two mutually spaced mirror devices and a substrate, the mirror devices each being arranged in parallel above the substrate and at least one of the mirror devices being movable with respect to the substrate.

Although the present invention has been fully described above on the basis of the preferred exemplary embodiment, it is not restricted thereto, but rather can be modified in many different ways.

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• EP 3064912 A1 [0003]

Claims (14)

Comprising interferometer device (10) - A Fabry-Perot interferometer (1) which comprises at least two mutually spaced mirror devices (SP1; SP2) and a substrate (2), the mirror devices (SP1; SP2) each being arranged in parallel above the substrate (2) and at least one of the mirror devices (SP1; SP2) is movable with respect to the substrate (2); - A base substrate (3) which comprises a cavity (4) and at least one electrical conductor track (5), the Fabry-Perot interferometer (1) being arranged on the base substrate (3) and covering the cavity (4); and - At least one detector device (6) which is arranged in the cavity (4) and is electrically contacted by means of the electrical conductor track (5). Interferometer device (10) according to Claim 1 , in which the Fabry-Perot interferometer (1) comprises an optical area (OB) which is suitable for filtering and transmission of a light and wherein the optical area (OB) is arranged above the cavity (4). Interferometer device (10) according to Claim 1 or 2 , in which the at least one electrical conductor track (5) is at least partially embedded in the base substrate (3) and extends into the cavity (4). Interferometer device (10) according to Claim 1 or 2 , in which the at least one electrical conductor track (5) is arranged on an upper side (O1) of the base substrate (3) facing the Fabry-Perot interferometer (1) and an electrical contact between the detector device (6) and the electrical conductor track (5) is made via a contact wire (7). Interferometer device (10) according to one of the Claims 1 to 4th , in which the substrate (2) above the cavity (4) comprises a recess (A) which protrudes laterally beyond the cavity (4). Interferometer device (10) according to one of the Claims 1 to 5 , in which the detector device comprises at least a first detector device (6a) and a second detector device (6b), which are sensitive to different wavelength ranges and are arranged in the cavity (4) one above the other or next to one another. Interferometer device (10) according to Claim 6 , in which the cavity (4) comprises a first cavity (4a) and a second cavity (4b) formed therein, which has a laterally smaller extent than the first cavity (4a), and wherein the first and / or the second detector device ( 6a; 6b) is arranged in the second cavity (4b). Interferometer device (10) according to Claim 7 , in which the second detector device (6b) is arranged in the second cavity (4b) and the first detector device (6a) is arranged in the first cavity (4a) and at least partially spans the second cavity (4b). Interferometer device (10) according to Claim 7 or 8th , in which an optical element (12) is arranged in the first cavity (4a) and above the first and / or second detector device (6a; 6b). Interferometer device (10) according to Claim 9 , in which the first detector device (6a) is sensitive to smaller wavelengths than the second detector device (6b). Interferometer device (10) according to one of the Claims 1 to 10 , in which the cavity (4; 4a; 4b) is at least partially covered with a reflective layer (8). Interferometer device (10) according to one of the Claims 1 to 11 , in which the base substrate (3) comprises at least one heat sink (9) which is in thermal contact with the detector device and / or with the Fabry-Perot interferometer (1). A method for producing an interferometer device (10) comprising the steps: - Providing (S1) a base substrate (3) with a cavity (4) and at least one electrical conductor track (5); - Arranging (S2) at least one detector device (6) in the cavity (4) and electrically contacting (S3) the detector device (6) with the electrical conductor track (5); and - Arranging (S4) a Fabry-Perot interferometer (1) which comprises at least two mutually spaced mirror devices (SP1; SP2) and a substrate (2), the mirror devices (SP1; SP2) each parallel above the substrate (2) are arranged and at least one of the mirror devices (SP1; SP2) is movable with respect to the substrate (2). Procedure according to Claim 13 , in which the contacting (S3) of the detector device (6) with a contact wire (7) takes place.

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