WO2008034663A1 - Sensor arrangement comprising a substrate and comprising a housing, and method for producing a sensor arrangement - Google Patents

Abstract

The invention is based on a sensor arrangement (10) comprising a substrate (20) and comprising a housing (30), wherein the housing (30) essentially completely surrounds the substrate (20) in a first substrate region (21), wherein the housing (30) is provided such that it is opened at least partly by means of an opening (33) in a second substrate region (22), wherein the second substrate region (22) is provided such that it projects from the housing (30) in the region of the opening (33). The heart of the invention consists in the fact that the substrate (20) is carried in a third substrate region (28) at least partly by a carrier (25) connected to the housing (30).

Description

 description

title

Sensor arrangement with a substrate and with a housing and method for producing a sensor arrangement

State of the art

The invention is based on a sensor arrangement with a substrate and with a housing according to the preamble of the main claim.

German Patent Application DE 199 29 026 A1 discloses a method for producing a pressure sensor in which a semiconductor pressure sensor is applied to a mounting section of a line grid, the semiconductor pressure sensor is electrically connected to contact sections of the line grid, and the line grid with the semiconductor pressure sensor is inserted into an injection molding tool and then the semiconductor pressure transducer is surrounded in the injection mold with a housing made of injection molding compound, wherein in the injection molding means are provided, through which a pressure feed for the Halbleitdruckaufnehmer of the casing and spray compound is recessed, wherein a punch in the injection mold through a gap to that of the Semiconductor pressure transducer remote side of the mounting portion is arranged spaced. Alternatively, it is known sensors that need access to external media, such. B. Pressure sensors to pack in Premold- housings. For this purpose, first the housing mold is injected and subsequently the chip is mounted in the already prefabricated housing and contacted accordingly. Since so-called premold housing shapes are relatively expensive compared to standard mold housings, attempts have already been made by means of the cited published patent application to pack pressure sensors in standard gold housings. For example, a partial area of the component surface is kept free for this purpose by a stamp or the like. A disadvantage of all existing housing forms is that the Sensor element is embedded in a plastic mass at least partially. Due to thermal expansion, the characteristic of the sensor element can be strongly influenced. This is for example possible because different thermal expansion coefficients lead to stresses in the sensor element, which gives rise to faulty measurements or functional failures.

From German patent application DE 102005038443, a sensor arrangement is known, in which the active sensor area of the sensor arrangement can be better decoupled from voltage entries which are induced by the housing. For this purpose, the substrate has a first substrate region and a second

Substrate area, wherein an active sensor area, such as a pressure sensor membrane or the like., Is located in the second substrate region and the second substrate region is provided protruding from the housing. In the transition region between the first and the second substrate region, the housing has an opening in the second substrate region. Characterized in that the second substrate region of the

Housing projecting, the housing is designed so that the sensor or the substrate with the active sensor area is embedded only on one side, namely in the region of its first substrate region, in the molding compound or in the housing material.

Disclosure of the invention

Advantages of the invention

The invention is based on a sensor arrangement with a substrate and with a

Housing, wherein the housing substantially completely surrounds the substrate in a first substrate region, wherein the housing is provided in a second substrate region at least partially open by means of an opening, wherein in the region of the opening, the second substrate region is provided protruding from the housing. The gist of the invention is that the substrate in a third substrate region is at least partially supported by a support connected to the housing. Advantageously, the substrate can not tilt so easily when mounting the sensor assembly. Advantageously, the proportion of the first substrate region on the entire substrate can thus be reduced in comparison to the prior art. Furthermore, the support of the substrate in the third substrate area assists in further support Mounting processes such as bonding the sensor array in the form of a semiconductor chip on a stamped grid, wire grid or carrier strip, as well as in the electrical contacting, for example by wire bonding.

An advantageous embodiment of the invention provides that the substrate in the third

Substrate area at least partially rests on the support. Advantageously, tilting of the substrate is prevented by the support, but at the same time a mechanical load on the substrate is minimized by forces acting on the support. Another advantageous embodiment of the invention provides that the substrate in the third substrate region is at least partially firmly connected to the carrier. It is particularly advantageous that the carrier is resilient. As a result, a mechanical load of the substrate is again kept as low as possible by forces acting on the carrier. An advantageous embodiment of the invention provides that the carrier is part of a line grid. The carrier is at least indirectly, connected via the line grid to the housing. Another advantageous

Embodiment provides that the carrier is directly connected to the housing. Advantageously, several carriers can be provided which secure the substrate at several points and in several directions against tilting.

drawing

1 shows a schematic plan view of a first embodiment of a sensor arrangement in the not previously published prior art, Figure 2 is a schematic representation of a sectional view through the

Sensor arrangement based on the section line AA of Figure 1,

Figure 3 is a schematic plan view of a second embodiment of a

Sensor arrangement in the not previously published prior art,

4 is a schematic sectional view of the second embodiment of the sensor arrangement based on the section line AA from FIG. 3, FIG.

FIG. 5 a schematic plan view of a first sensor arrangement according to the invention, FIG. 6 a schematic representation of a sectional view through the first sensor arrangement according to the invention, based on the section line AA from FIG. 5, FIG. 7 a schematic representation of the first sensor arrangement according to the invention in phantom, and FIG Figure 8 is a schematic representation of a second sensor arrangement according to the invention in a transparent view.

Exemplary embodiments

Exemplary embodiments of the invention are illustrated in the figures and described below in the description. Like reference numerals denote like elements unless the description expressly deviates therefrom.

1 shows a schematic plan view of a first embodiment of a sensor arrangement is shown in the not previously published prior art. This sensor arrangement 10 comprises a housing 30 and a substrate 20. The substrate material is in particular as a semiconductor material or as a composite substrate, for example of

Wafers of different or the same materials provided. In the following, the substrate material is referred to as substrate 20. The substrate 20 has a first region 21 and a second region 22, wherein in the second region 22, an active region 23 is shown separately, which serves for sensing or for detecting a size to be measured by means of the sensor arrangement 10. In the second substrate region 22, an opening 33 is provided in the housing 30 in the transition region to the first substrate region 21, so that the second substrate region 22 can protrude. The variable which can be detected by means of the active region 23 is, in particular, one which can be detected only by means of at least indirect contact between the second substrate region 22 or in particular the active region 23 and a medium not shown in the figures. The medium may be, for example, a gas whose pressure is to be measured by means of a pressure measuring membrane as the active region 23. In this case, the medium, such as air or another gas, access to the area 23, d. H. in particular to the pressure measuring membrane. This access to the active region 23 is realized by the second substrate region

22 protrudes from the housing 30 and that the first substrate portion 21 is embedded in the housing 30. FIG. 1 shows a section line AA, with FIG. 2, with certain modifications, being a schematic illustration of the sensor arrangement 10 according to the invention according to the section line AA from FIG. In Figure 1 is still seen that from the housing 30 in particular connecting elements 31, such as For example, pins or Kontaktierungsbeinchen or the like., Stand out. However, it is also possible that no contacting elements 31 protrude from the housing 30, but that on the top, the bottom and / or the lateral surfaces of the housing 30 contact surfaces (not shown) are present, the contacting of the device or the sensor assembly serve, for example by means of a flip-chip mounting option, BGA housing or the like. The housing 30 is

FIG. 2 shows a schematic representation of a sectional representation through the sensor arrangement on the basis of the section line AA from FIG. 1. In FIG. 2, the sensor arrangement 10 is provided with the first substrate region 21, the second substrate region 22, the active region 23, the housing 30 and the opening 33 shown. The housing 30 is an injection-molded housing, which encloses the elements arranged therein. In addition, a specific exemplary embodiment is indicated in FIG. 2, in which, in addition to the substrate 20, a further substrate 26 is present, which, for example, further circuit means for evaluating the signals of the active region

23 includes. For this purpose, the substrate 20 and the further substrate 26 are connected to one another by means of a connecting line 27, in particular in the form of a bonding wire 27. In the example of the arrangement of FIG. 2, both the substrate 20 and the further substrate 26 are arranged on a so-called conductive grid 25, which is also referred to as the leadframe 25, or adhesively bonded or otherwise secured to the leadframe 25.

FIG. 3 shows a schematic representation of a second embodiment of a sensor arrangement 10 in the prior art, which has not been published before. Again, the substrate 20 has the first substrate region 21 and the second

Substrate region 22, wherein the second substrate portion 22 on the one hand comprises the active region 23 and on the other hand protrudes from the housing 30 at the opening 33. In contrast to the first embodiment, however, the housing 30 has an extension portion 35 which extends substantially in the main plane of the substrate 20 around the second substrate portion 22 and thus the second

Protected substrate region 22 in particular from mechanical effects. In this case, the additional region 35 or extension region 35 of the housing protects the second substrate region 22 without mechanical forces, for example by different temperature coefficients or the like, on the second substrate region 22 and in particular on the active region 23 of the sensor arrangement. This is because of the Extension region 35 maintains a distance from the second substrate region 22, wherein this distance is indicated by the reference numeral 24 in Figure 3. FIG. 3 also has a section line AA, with FIG. 4 essentially showing a sectional illustration (with certain deviations) along section line AA from FIG.

FIG. 4 shows the mentioned, schematic sectional illustration along the section line AA (with deviations) from FIG. 3, the sensor arrangement 10 again comprising the substrate 20, the first substrate region 21, the second substrate region 22, the active region 23, the further substrate 26, the extension area 35 and the

Line grid 25 and the leadframe 25 includes.

FIG. 5 shows a schematic plan view of a first sensor arrangement according to the invention. Shown are first from the figure 3 known elements. The substrate 20 has a first substrate region 21, which is not visible here. The

Substrate 20 further has a second substrate region 22 and, distinguished therefrom by a dot-dash line, a third substrate region 28, the second and third substrate regions 22 and 28 being arranged in the opening 33 of the housing 30. The third substrate region 28 is at least partially supported by a carrier 25. This carrier 25 may be part of the line grid 25, as in this

Embodiment shown. The carrier 25 may be disposed on or in the housing 30. FIG. 5 also has a section line AA, with FIG. 6 essentially showing a sectional view along the section line AA from FIG.

FIG. 6 shows a schematic representation of a sectional illustration through a first sensor arrangement according to the invention based on the section line AA from FIG. 5. The support of the substrate 20 in the third substrate region 28 can be recognized by means of the carrier 25. The first substrate region 21 is designed to be significantly smaller than in the state of the technique. By supporting the substrate 20 in the third substrate region 28 by the carrier 25, tilting of the substrate 20 during assembly of the sensor arrangement 10 is nevertheless precluded. The housing 30 is in this example an injection-molded housing, which encloses the elements arranged therein. FIG. 7 shows a schematic representation of the first sensor arrangement according to the invention in phantom. The carrier 25 supports the substrate 20 in the third substrate region 28 in the entire overlap area by mere support of the substrate 20 on the carrier 25. The substrate 20 and the carrier 25 are not fixedly connected to each other here. The carrier 25 is in this embodiment with the rest

Wiring 25 connected.

FIG. 8 shows a schematic representation of a second sensor arrangement according to the invention in phantom. The carrier 25 has two formations in the region of the third substrate region 28 and carries the substrate 20 substantially only selectively in this region. The carrier 25 is furthermore firmly connected to the substrate 20 in the third substrate region 28. The connection may be, for example, an adhesive connection. In addition, the carrier 25 in the region of the opening 33 of the housing 30 has a resilient structure, which is indicated schematically here. The resilient structure serves to mechanical forces, the carrier 25 on the substrate 20 in the third

Substrate area 28 could exercise to minimize. The carrier 25 is connected in this embodiment only to the housing 30 and not to the line grid 25. However, it may alternatively be connected to the line grid 25.

Claims

claims A sensor assembly (10) having a substrate (20) and a housing (30), said housing (30) substantially completely surrounding said substrate (20) in a first substrate region (21), said housing (30) being in a second Substrate region (22) is provided at least partially open by means of an opening (33), wherein in the region of the opening (33) of the second substrate region (22) from the housing (30) is provided projecting, characterized in that the substrate (20) in a third substrate region (28) at least partially through a Carrier (25) which is connected to the housing (30) is worn. 2. Sensor arrangement (10) according to claim 1, characterized in that the substrate (20) in the third substrate region (28) at least partially rests on the carrier (25). 3. Sensor arrangement (10) according to claim 1, characterized in that the substrate (20) in the third substrate region (28) at least partially fixedly connected to the carrier (25). 4. Sensor arrangement (10) according to one of the preceding claims 1 to 3, characterized in that the carrier (25) is resilient. 5. Sensor arrangement (10) according to one of the preceding claims, characterized in that the carrier (25) is part of a line grid.