TW201810449A - Arrangement comprising a carrier and a housing body, and method for producing an arrangement comprising a component - Google Patents

Abstract

An arrangement (1) comprising a carrier (3) and a housing body (4) is disclosed. The housing body (4) is arranged on the carrier (3) and bounds a cavity (9) for receiving at least one component (16). In the cavity (9), passivation (19) made of a first material is provided in a first region (21) and made of a second material is provided in a second region (22) different from the first region (21). The first material has a higher modulus of elasticity and/or a higher hardness as compared with the second material, wherein the first region (21) covers a sub-area (20) of the carrier (3), and the second region (22) covers a sub-area (14) of the housing body (4). The component (16) is arranged in the second region (22).

Description

Device including carrier and housing, and method of manufacturing device including component

The large system of the present invention relates to a housing for components. In particular, the present invention relates to a housing for electronic and/or micromechanical components, the housing having a carrier and a housing having, for example, a cavity arranged to receive a sensor element.

Depending on the purpose required by us, the housing used for electronic components is subject to various demands, which is caused by the type of components arranged in the housing. Known housings for sensors.

In DE 10 2011 084 582 B3, a micromechanical sensor device with a molded package and a corresponding manufacturing method are described. The sensor device includes a substrate, a circuit chip applied to the substrate, and a molded package, in which the circuit chip is packaged. The molded package has a cavity above the circuit wafer (in which the sensor chip is disposed), and a channel hole in the cavity (through which the electrical connection of the sensor chip is guided).

It is also necessary to provide a housing which is satisfactory for different types of components (for example, such as sensors and electronic components for sensors) at the same time. The components should be sufficiently protected from environmental influences; in addition, the possibility of safe contact with the corresponding components must be additionally ensured. In addition, when necessary, proper access to the member becomes possible. Therefore, as far as the sensor element is concerned, in order to perform Measurement usually requires entering the medium entrance of the sensor element. It should also be noted that the sensor element is relatively sensitive to the thermomechanical and mechanical stresses occurring between the housing and the carrier.

There is therefore a need for a housing for components, where each component is sufficiently passivated and protected from environmental influences, and at the same time no negative effects (such as thermo-mechanical or mechanical stress) are applied to the components.

A device including a carrier and a housing as claimed in the independent patent technical solution 1 and a method for manufacturing a device including a component according to the dependent patent technical solution 9 are provided.

Other optimizations are specified in the attached technical solution.

According to a first aspect of the invention, a device comprising a carrier and a housing is produced, wherein the housing is arranged on the carrier and defines a cavity for accommodating at least one component. In the cavity, a passivation area made of a first material is provided in the first area, and a passivation area made of a second material is provided in the second area, where the second area is different from the first area. The first material has a higher modulus of elasticity and/or a higher hardness than the second material. Furthermore, the first area covers a sub-region of the carrier and the second area covers a sub-region of the housing. The components are arranged in the second area.

With this device, the passivation area of the component can be significantly improved, resulting in a two-part passivation area, which can meet different requirements regarding the passivation area in the first and second areas of the passivation area, respectively. For example, a two-part potting compound can be used, and with the two-part potting compound, the mutual exclusion requirement can be selectively implemented by means of two materials. In addition, the stability of the cavity package can be significantly improved compared to the prior art.

According to a preferred embodiment, the cavity forms a channel opening to the carrier, which is at least partially filled with the first material.

For this purpose, advantageously, it is possible to choose a material for the first region that is more suitable for protecting the sub-regions of the carrier compared to other materials or compared to the second material and therefore has a sufficiently high modulus of elasticity And/or a suitably high hardness. In addition, a particularly stable passivation of the carrier can be achieved in this way.

Furthermore, the housing may form a protrusion defining a cavity, wherein the member is arranged on the protrusion, and the second material covers the protrusion.

The second material can be advantageously selected so that the sub-regions of the housing or the components located thereon are protected and at the same time subject to as little thermodynamic and mechanical stress as possible. In particular, stress-sensitive components (which have a different expansion coefficient and/or different flexibility compared to the plastic of the carrier) are not placed on the carrier, which means to avoid thermal loads such as those that occur during welding and on the component, for example Mechanical and thermomechanical stress. In addition, the components in the second area can be sufficiently protected, for example, with respect to environmental loads such as moisture penetration.

According to a specific example of the invention, the member in the second area is formed as a sensor element, in particular as a pressure sensor.

Therefore, advantageously, it is possible to implement the sensor device, in which the maintenance of the sensor characteristic curve is ensured, since adverse effects on the sensor characteristic curve can be prevented especially during assembly. In particular, the advantages of a pre-molded housing can be used here, where the sensor is placed on a normal, extremely rigid plastic substrate, while the other sides of the sensor are only surrounded by a suitable protective passivation area.

Furthermore, between the sensor element and the outer side of the housing, a fluid connection may be formed in the second material and/or in the housing.

Therefore, if necessary, the components of the sensor element can be set aside, advantageously providing a sensor device with a simple implemented feed opening for feeding air pressure to the sensor, for example. specific In other words, the feed opening here can be imprinted more simply than in a pure mold housing, in which the component or sensor is surrounded by the housing.

The other component is preferably embedded in the housing.

Therefore, this component is preferably selected so that it does not require a media inlet can be particularly well protected from environmental influences, since it is directly surrounded by the housing.

According to an advantageous embodiment, the first area has a lower thickness than the second area, where the first material has, for example, epoxy resin or lacquer.

Therefore, advantageously, the first component of the two-part passivation zone can protect the carrier with a hard and thin potting compound. Dense and hard potting compounds keep the damage medium away from sensitive structures for significantly longer than softer materials. In particular, lower permeability with respect to media such as air, moisture and exhaust gases, halides, alkalis or acids can be achieved in the first zone. In addition, the thinner coating ensures that there is no thermo-mechanical stress leading to cracking and detachment, which will be additionally expected in the case of larger volumes.

The second material may have a gel, in particular, a polysiloxane gel.

Compared to plastics such as epoxy resins, for example, this material has the advantage that it can be used as a complete potting compound on components. The fact that the material is used in the second region means that in addition, in the second region, stress-induced characteristic curve changes can be avoided, such as cracking and delamination due to thermomechanical stress can be avoided.

Therefore, in general, the second component of the two-part passivation zone can protect both the sensor element and the volume of the cavity with an incompressible potting compound made of a soft material with a lower modulus of elasticity. Incompressibility is mentioned in many applications to ensure unimpeded signal transmission, and softness helps to avoid any effects caused by thermomechanical stress on the sensor element.

The housing can be manufactured, for example, by plastic overmoulding.

Therefore, the housing can be manufactured in an efficient manner, with the help of plastic, which also ensures good protection of the components with regard to environmental impact. Advantageously, it is possible to implement a mold pre-molded housing with over-molded components on a circuit board or lead frame as a carrier with a pre-molded cavity and a two-part passivation zone.

According to a specific example, the component can be routed to connect to the electrical connection on the carrier by means of a wire connection, wherein the connection is arranged in the first area and covered by the first material, wherein the wire bonding passes through the first area and passes The second area.

In particular, in combination with the aforementioned thinner and harder potting compound in the first region, this specific example can be particularly advantageously used in the case of sensitive circuit boards as carriers, where The bonding area where the component contacts can be provided on the circuit board. Due to the thinner local application in the foot area, the harder area can be kept away from the sensor element whose function can be interrupted by thermo-mechanical stress. The two-part passivation zone can advantageously provide dense protection for the circuit board and the joint connections on the circuit board from media such as exhaust gases and halides without exerting any negative effects on harder materials.

According to a second aspect of the present invention, a method for manufacturing a device having a component is designed, wherein the method includes the steps of providing a carrier, overmolding the carrier with a mold material so that a cavity is formed, wherein the cavity reaches The upper side of the carrier; placing the member in the cavity; introducing the first material into the cavity, wherein the first material is coated on the surface of the carrier in the cavity; and coating the second material into the cavity, Wherein the component is covered by the second material, and wherein the second material has a lower modulus of elasticity and/or higher hardness than the first material.

According to a preferred embodiment, the second material is also coated on the first material.

In addition, the first material is preferably coated with a thinner layer than the second material.

In addition, the first material may cover the entire surface of the carrier in the cavity, and the second material may cover the entire component.

In general, with the aspect of the invention, advantageously, it is possible to use a molded housing (where the component is built on a carrier such as a circuit board and then overmolded with plastic) and a pre-molded housing (where first Shaped carrier) The advantages of both, in which the area is left, for example, for making electrical contact, and then components are added and in contact with it, wherein the improved passivation area is provided by the aspect of the invention. In other words, a combination of both of the aforementioned housing types can be provided, which means that the adapting member can be overmolded and the cutout can be left for subsequent addition of other members, and at the same time passivation of all members can be ensured in a way that takes special consideration of the function of the member.

Components that are less sensitive to stress and do not require any gas to enter can be insert-molded, and the stress-sensitive sensor element is established in the shaped pre-molded cavity. Therefore, it is achieved to protect the embedded molded member from environmental influences, and at the same time to ensure that the sensor element has a connection to the outside, because the element is arranged in the pre-molded cavity.

In particular, the mold pre-molded housing can be advantageously implemented on the circuit board substrate in order to protect components that do not require any medium to enter the mold body, and at the same time to manufacture a pre-molded area in which the sensor element consists of two Part of the passivation area is protected from media influence.

The aspect of the present invention can therefore be implemented with both the lead frame and the substrate as a carrier.

The preferred embodiments of the present invention will be explained in more detail below using the accompanying drawings, in which: 1 shows a schematic cross-sectional view of a device including a carrier and a housing according to a first specific example of the present invention, 2 shows a schematic plan view of a device including a carrier and a housing according to a second specific example of the present invention, 3 shows a schematic cross-sectional view of a device including a carrier and a housing according to a third specific example of the present invention, and 4 shows a flowchart of a method for manufacturing a device including components according to a specific example of the present invention.

In the drawings, the same reference refers to the same or functionally identical elements.

FIG. 1 shows a schematic cross-sectional view of a device 1 configured as a sensor device 2 including a carrier 3 and a housing 4 according to a first specific example of the present invention. The carrier 3 serves as a substrate of the housing 4, and the housing has an upper side 6 and a lower side 5, where the lower side 5 covers most of the carrier 3. The carrier 3 can in principle be configured as a lead frame or a circuit board, wherein according to the specific example shown in this article, the carrier 3 is a circuit board, the circuit board is equipped with a large number of electronic components 7, one component 7 of the circuit board by way of example Shown in the diagram. The component 7 is encapsulated by the housing 4 and electrically connected to the circuit board (ie the carrier 3) by means of a conductive connection 8. The conductive connection 8 has, for example, wire bonding. According to the specific example shown here, the housing 4 is made of plastic and forms the wafer housing of the component 7. The housing 4 can be made, for example, by injection molding. Since the component 7 is encapsulated by the housing 4, the housing thus acts as a mold shell. As shown in the drawing, the component 7 in the housing 4 is protected from the environment.

The housing 4 also forms a cavity 9 which is defined by the side wall 10 (ie, inside the housing 4 Wall) limit. In a plan view, the defined side walls 10 as shown in FIG. 2 can be continuously connected to each other on the outer circumference of the cavity 9. In the cross-sectional view shown in FIG. 1, the cavity 9 partly has a stepped cross-section, because the housing 4 is shaped so that the cavity 9 is further defined by the protrusion 11 protruding into the cavity 9. In the cross-sectional view, the side wall 15 of the lower side 13, the upper side 14 and the protrusion 11 can also be seen.

The protrusion 11 of the housing 4 covers a sub-region of the carrier 3, wherein the underside 13 of the protrusion 11 represents a part of the underside 5 of the housing. The side wall 15 of the protrusion 11 extends parallel to the side wall or inner wall 10 of the housing 4, however, the housing is not limited to this shape. The cavity 9 also has an opening on the upper side 6 of the housing 4. Furthermore, the cavity 9 forms a channel opening 12 leading to the carrier 3 so that the carrier 4 in the area below the channel opening 12 is not covered by the housing 4.

The cavity 9 serves to accommodate the component 16 which is not directly placed on the circuit board 3. The member 16 is arranged on the upper side 14 of the protrusion 11 and is connected to the circuit board 3 by means of a wire connection 17. The circuit board 3 is also provided with related bonding legs 18 as the connection of the wire bonding 17. The combining leg 18 is an element of the structure of the circuit board 3 (not shown in the drawings). The component 16 in the cavity 9 is herein a sensor element, which may have a micromechanical sensor element. In particular, the member 16 may be a pressure sensor. The related electronic components of the sensor element are at least partially placed on the circuit board 3. The electronic part has, for example, the component 7 and may also have other elements not specifically shown in the drawings for simplicity. These can also be arranged on the circuit board 3 in the area of the channel opening 12.

A passivation area 19 is provided in the cavity 9 for passivating the component (ie, the sensor element 16) and for passivating the portion of the circuit board 3 in the area of the passage opening 12 of the cavity 9. For this purpose, the passivation region 19 has a first region 21 of a first material and a second region 22 of a second material. The first area 21 of the passivation area 19 covers the sub-area of the circuit board 3 that is not covered by the lower side 5 of the housing 4. The second area 22 of the passivation area 19 covers the sub-area 14 of the housing 4, more precisely, especially the upper side 14 of the protrusion 11. In addition, the second region 22 also covers a part of the side surface 10. In this way, the sensor element 16 arranged on the protrusion 11 is arranged in the second passivation area 19 or embedded in the second material. In the specific example shown, the second region 22 of the passivation region 19 also extends above the first region 21, so that the first region 21 and the second region 22 have a common interface 20. According to this specific example, the interface is parallel to The circuit board 3 extends. Therefore, the passivation region 19 can be manufactured particularly simply, and the stability can be increased. The thickness d _{1 of the} first region 21 is smaller than the thickness d _{2 of the} second region 22. In particular, the thickness d _{2 of the} second region 22 is selected so that the second region 22 surrounds the sensor element 16 and the first region 21 covers the carrier 3.

The two regions 21, 22 of the passivation zone 19 can adopt all conceivable suitable shapes depending on the type, number and arrangement of the components to be protected. Here, the term "region" related to this connection is not limited to the description of the two-dimensional size, as has been made clear from the foregoing specific examples. In addition, "different" means that the regions have at most a common interface but no same volume range.

The first material has, for example, epoxy resin or lacquer, and the second material has a gel, specifically, for example, polysiloxane gel.

The cavity 9 is configured as a so-called pre-molded cavity, in which the housing 4 acts as a pre-molded package or pre-molded housing, which protects the area of the carrier 3 covered by the lower side 5 of the housing 4. In addition, since the component 7 is molded into the housing 4, the two-part passivated mold pre-molded housing is therefore implemented by the device 1 and in particular by the housing 4.

2 shows a schematic plan view of a device 24 including a carrier 3 and a housing 4 according to a second specific example of the present invention. The device 24 substantially corresponds to the device 1 in FIG. 1. because To be different from the first specific example according to FIG. 1, the carrier 3 according to the second specific example is formed as a lead frame (that is, as a connection frame). The lead frame 3 is arranged under the housing 4; the plan view shown in FIG. 2 corresponds to the position behind the housing 4 with respect to the direction of the plane into the page. As shown in FIG. 2, the lead frame 3 has a large number of connections 25, which are clearly illustrated schematically in the drawings. The connection 25 can be used to mount the device 24 in a variant of this specific example, but in principle is not limited to a specific shape.

Furthermore, the device 24 has a large number of components 7, 26 moulded into the housing 4, the two components 7, 26 are shown in the drawings by way of example for the purpose of clarity. On the one hand the electrical connection between the components 7, 26 on the circuit board and on the other hand the sensing element 16 are not explicitly shown. As further shown in FIG. 2, the sidewall 10 of the cavity forms a closed rectangle. However, the shapes and arrangements of the cavity 9 and the channel opening 12 are not limited to specific shapes, and may be adjusted depending on the application. Therefore, according to this specific example, the width b _{12 of the} channel opening 12 is smaller than the width b _{9 of the} cavity ₉ . However, according to other specific examples, the width of the channel opening 12 may also correspond to the width of the cavity 9.

3 shows a schematic cross-sectional view of a device 1 including a carrier 3 and a housing 4 according to a third specific example of the present invention. The device 1 according to FIG. 3 substantially corresponds to the device in FIG. 1. Since it is different from FIG. 1, in FIG. 3, the fluid connection 23 is additionally illustrated, and the connection is configured as a passage opening to the second region 22. In other words, the second material is cut in the sub-region of the second region 22 above the sensor element 16. Therefore, for example, the pressure wave or pressure change to be sensed by the sensor element 16 can be transmitted better. According to other specific examples, the separate fluid connection 23 is ignored, where the second material itself acts as a carrier for transmission or is selected so that the media to be detected is not shielded in an unfavorable manner.

FIG. 4 shows a device for manufacturing a component according to a specific example of the invention Set the method. In principle, the method has the steps described below. In step S100, a carrier is provided. The carrier may be a lead frame or a circuit board. The carrier may have a suitable configuration in the form of conductors or connections and components placed thereon. In step S101, the carrier is overmolded using a mold material, and the cavity is also formed. The cavity is used to accommodate other components. In particular, the component can be accommodated in the cavity, the component being arranged on the housing instead of the cavity on the carrier. The cavity reaches the surface of the carrier. In step S102, the component is then placed in the cavity. In step S103, the first material is introduced into the cavity, and the first material is coated on the surface of the carrier. In step S104, the second material is introduced into the cavity, and the member placed in the cavity is covered with the second material. The material is selected so that the second material has a lower modulus of elasticity and/or a higher hardness than the first material.

It goes without saying that the order of the steps can be changed as needed and does not have to strictly follow the order illustrated in FIG. 4. In principle, it is a matter of material selection and its passivation characteristics and possible effects on the covered or embedded components and areas. For example, it is conceivable that the second area is first manufactured by means of a mask and then the first material is applied. In this specific example, the fluid connection configured as an opening may also be provided in the first area. In addition, for example, it is also conceivable that although this is not explicitly stated in the above description, the housing is formed first and then the cavity is formed in the housing.

Claims (13)

A device (1) comprising a carrier (3) and a housing (4), the housing being arranged on the carrier (3) and defining a cavity (9) for accommodating at least one component (16), wherein In the cavity (9), a passivation area (19) made of a first material is provided in a first area (21), and a passivation area made of a second material is provided in a different area than the first area (21) in a second region (22), wherein the first material has a higher elastic modulus and/or a higher hardness than the second material, wherein the first region (21) covers the A sub-region of the carrier (3), and the second region (22) covers a sub-region (14) of the housing (4), wherein the member (16) is arranged in the second region (22). A device (1) as claimed in item 1 of the patent application, wherein the cavity (9) forms a passage opening (12) to the carrier (3) at least partially filled with the first material, and wherein the housing (4) A protrusion (11) defining the cavity (9) is additionally formed, wherein the member (16) is arranged on the protrusion (11) and the second material covers the protrusion (11). For example, in the device (1) of item 1 or item 2 of the patent application scope, another member (7) is embedded in the housing (4). The device (1) according to any one of the aforementioned patent applications, wherein the first region (21) has a lower thickness (d ₁ ) than the second region (22). The device (1) according to any one of the aforementioned patent applications, wherein the housing (4) is prepared by plastic overmolding. The device (1) according to any one of the aforementioned patent applications, wherein the member (16) in the second area (22) is formed as a sensor element, in particular as a pressure sensor. The device (1) according to item 6 of the patent application scope, in which the sensor element and an external Between the sides, a fluid connection (23) is formed in the second material and/or in the housing (4). The device (1) according to any one of the items 3 to 7 of the patent application range, wherein the member (16) is connected to one of the electrical connections on the carrier (3) by means of a wire connection (17), wherein the The connection (18) is arranged in the first area (21) and covered by the first material, wherein the wire bonding passes through the first area (21) and through the second area (22). A method for manufacturing a device (1) having a component (16), comprising the steps of providing a carrier (3) and overmolding the carrier (3) using a mold material so that a cavity is formed (9), wherein the cavity (9) reaches an upper side (6) of the carrier (3), a member (16) is placed in the cavity (9), a first material is introduced into the cavity In the cavity (9), wherein the first material is coated on the surface of the carrier (3) in the cavity (9), and a second material is coated in the cavity (9), wherein the member (16) Covered by the second material, wherein the second material has a lower modulus of elasticity and/or a higher hardness than the first material. For example, in the method of claim 9, the second material is also coated on the first material. The method of any one of claims 9 and 10, wherein the first material is coated in a thinner layer than the second material. A method according to any one of claims 9 to 11, wherein the first material covers the entire surface of the carrier (3) in the cavity (9), and wherein the second material covers The whole component (16). The method as in any one of the patent application items 9 to 12, wherein the first material used is an epoxy resin or a lacquer, and one of the gels, especially a silicone gel, is used in The second material.