Package structure

Abstract

The utility model discloses a packaging structure which comprises a temperature detection element and a packaging substrate. The temperature detection element comprises a first element surface and a second element surface which are opposite to each other, and the first element surface is provided with a bonding pad; the package substrate includes: a substrate main body disposed on a first element surface side of the temperature detection element; the first lead is connected with the substrate main body; and the second lead is electrically connected with the bonding pad. Compared with a packaging scheme that the first element surface is arranged back to the surface of the substrate in the prior art, the heat in the packaging structure can be directly transferred to the first element surface, the response time of the temperature detection element is shortened, and the sensitivity of the temperature detection element is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of semiconductor temperature sensor packaging, in particular to a packaging structure for improving the response speed of a temperature detection element. Background Art

[0002] Temperature sensors are widely used in the field of semiconductor devices. They are generally embedded with temperature-sensitive detection devices. The devices sense the temperature and feedback different signals. The feedback is achieved through different circuits. At present, temperature sensors use devices that integrate capacitors, resistors, and inductors as temperature sensors. Changes in temperature cause changes in the internal capacitance, resistance, and inductance values, which in turn lead to changes in the output signal voltage and current.

[0003] Generally, the back of the temperature sensor chip is mounted on the substrate, and the heat in the package structure is transferred from the substrate to the back of the chip. Then the heat is gradually transferred from the back of the chip to the front of the temperature sensor chip. The circuit on the front of the chip recognizes the information and outputs a feedback signal. In this heat transfer process, the heat needs to be transferred from the back of the chip to the active area on the front of the chip. The heat transfer time is long, and there are problems such as extended temperature sensor response time. Utility Model Content

[0004] The utility model aims to provide a packaging structure, which solves the problems of long induction response time and low sensitivity of temperature detection elements in the prior art.

[0005] In order to achieve one of the above-mentioned purposes of the utility model, an embodiment of the utility model provides a packaging structure, including a temperature detection element and a packaging substrate; the temperature detection element includes a first component surface and a second component surface opposite to each other, and the first component surface is provided with a pad; the packaging substrate includes:

[0006] A substrate body, arranged on one side of the first element surface of the temperature detection element;

[0007] A first lead connected to the substrate body;

[0008] The second lead is electrically connected to the pad.

[0009] As a further improvement of an embodiment of the utility model, it also includes a dielectric layer, and the dielectric layer is arranged between the first component surface and the substrate body.

[0010] As a further improvement of an embodiment of the utility model, the thermal conductivity of the dielectric layer is greater than 10 W / mK.

[0011] As a further improvement of an embodiment of the utility model, it also includes a first thermally conductive adhesive layer, which is arranged between the dielectric layer and the substrate body and is used to bond and fix the dielectric layer to the surface of the substrate body.

[0012] As a further improvement of an embodiment of the utility model, it also includes a second thermally conductive adhesive layer, which is arranged between the first element surface and the dielectric layer and is used to bond and fix the temperature detection element to a side surface of the dielectric layer away from the substrate body.

[0013] As a further improvement of an embodiment of the utility model, it also includes a plastic package, which covers the temperature detection element, the substrate body, and part of the first lead and part of the second lead close to the substrate body.

[0014] As a further improvement of an embodiment of the utility model, it also includes a metal welding wire, the metal welding wire connects the welding pad and the second lead, and the plastic package also covers the metal welding wire.

[0015] As a further improvement of an embodiment of the utility model, the dielectric layer extends and connects the substrate body and the surface of the second lead facing the first element surface, and the temperature detection element is arranged on the side of the dielectric layer away from the substrate body;

[0016] A metal circuit layer connecting the pad and the second lead is disposed in the dielectric layer.

[0017] As a further improvement of an embodiment of the utility model, a metal solder ball is arranged between the temperature detection element and the dielectric layer, which is used to fix the temperature detection element to the side of the dielectric layer away from the substrate body and connect the solder pad and the metal circuit layer.

[0018] As a further improvement of an embodiment of the utility model, it also includes a third thermal conductive adhesive layer, which is arranged between the dielectric layer and the second lead and is used to bond and fix the dielectric layer to the second lead.

[0019] The beneficial effect of the present utility model is that the first component surface of the temperature detection element with the solder pad is arranged toward the surface of the substrate main body, and the heat generated in the packaging structure can be directly transferred to the first component surface of the temperature detection element through the substrate, and the circuit on the first component surface recognizes the temperature information and outputs a feedback signal. Compared with the packaging scheme in the prior art in which the first component surface is arranged with its back to the substrate surface, the time for the heat in the packaging structure to be transferred to the first component surface is short in the present application, which can shorten the response time of the temperature detection element and improve the sensitivity of the temperature detection element. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic diagram of the packaging structure in Example 1 of the utility model;

[0021] Figure 2 is a schematic diagram of a packaging method flow corresponding to the packaging structure in Example 1;

[0022] Figure 3 This is a schematic diagram of the packaging structure in Example 2 of the utility model;

[0023] Figure 4 It is a schematic diagram of the packaging method flow corresponding to the packaging structure in Example 2. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical solutions and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below in combination with the specific implementation methods of this application and the corresponding drawings. Obviously, the described implementation methods are only part of the implementation methods of this application, not all of the implementation methods. Based on the implementation methods in this application, all other implementation methods obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0025] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0026] The utility model provides a packaging structure, comprising a temperature detection element and a packaging substrate; the temperature detection element comprises a first component surface and a second component surface opposite to each other, and the first component surface is provided with a soldering pad; the packaging substrate comprises: a substrate body, which is arranged on one side of the first component surface of the temperature detection element; a first lead, which is connected to the substrate body; and a second lead, which is electrically connected to the soldering pad.

[0027] Example 1

[0028] like Figure 1 , is a packaging structure provided in Example 1 of the utility model, including a temperature detection element 100 and a packaging substrate 200.

[0029] The temperature detection element 100 includes a first element surface 110 and a second element surface 120 that are opposite to each other. A pad 130 is disposed on the first element surface 110 .

[0030] Specifically, the second component surface 120 is the surface of the silicon wafer, and other electrical components, such as capacitors, inductors, resistors, or devices integrated with the above components, are also arranged on the first component surface 110. When the heat in the package structure is transferred to the first component surface 110, it will cause changes in the internal parameters of the components such as capacitors, inductors and resistors on the first component surface 110, thereby causing changes in the voltage signal and current signal output by the pad 130 to the external substrate or device, so as to achieve the purpose of testing the temperature in the package structure.

[0031] Specifically, the temperature detection element 100 may be a thermistor, a thermocouple, and an integrated circuit chip composed of at least one of the above components, and is used to detect the temperature of heat generated in the packaging structure.

[0032] The package substrate 200 includes a substrate body 210 , a first lead 220 and a second lead 230 . The substrate body 210 is disposed on one side of the first element surface 110 of the temperature detection element 100 . The first lead 220 is connected to the substrate body 210 . The second lead 230 is electrically connected to the pad 130 on the first element surface 110 .

[0033] Specifically, the second lead 230 is disposed on the side of the substrate body 210 away from the first lead 220 , and the second lead 230 is spaced apart from the substrate body 210 and electrically isolated, and the pad 130 on the first element surface 110 of the temperature detection element 100 is electrically connected to the second lead 230 .

[0034] In this embodiment, the packaging substrate 200 includes but is not limited to a common metal lead frame and a multi-layer MIS (Molded Interconnect System) substrate (a packaging substrate for a molded internal connection system). The metal frame can be made of materials such as copper, aluminum, and copper-aluminum alloys by stamping or etching. The MIS substrate uses processes such as electroplating, stamping, and etching lead frames. When etching the lead frame, a pattern is etched from one side of the lead frame, and then a pattern is etched from the other side to form a two-layer metal layer structure. The above process is repeated to form a multi-layer substrate, and different substrates are electrically interconnected through internal conductive through holes to form a multi-layer substrate structure.

[0035] Of course, the packaging substrate 200 can also be an alumina ceramic substrate, an aluminum nitride ceramic substrate, a silicon nitride ceramic substrate, and a silicon carbide ceramic substrate with high thermal conductivity, and form an electrical connection with the inside and outside of the device by adopting a copper cladding (DBC, Direct Bonded Copper) process or an active metal brazing (AMB, Active Metal Brazing) process.

[0036] Furthermore, as the temperature detection element 100 is gradually developing towards high power, the voltage inside the temperature detection element 100 is getting higher and higher, and the temperature detection element 100 is prone to breakdown and other failure risks under continuous high voltage. Therefore, in this embodiment, the packaging structure also includes a dielectric layer 300, and the dielectric layer 300 is set as a spacer dielectric material, that is, an electrical insulator.

[0037] The dielectric layer 300 is arranged between the first element surface 110 and the substrate body 210 to electrically isolate the temperature detection element 100 from the substrate body 210, protect the temperature detection element 100 from the influence of the electric field caused by the high voltage on the substrate body 210, and avoid the temperature detection element 100 from being broken down by high voltage.

[0038] Specifically, the dielectric layer 300 may be made of an organic composite material with high thermal conductivity, or an inorganic insulating dielectric material with high thermal conductivity, such as alumina ceramics, aluminum nitride ceramics, silicon nitride ceramics, and silicon carbide ceramics.

[0039] More specifically, the thermal conductivity of the dielectric layer 300 is greater than 10 W / mK to ensure the heat conduction efficiency in the packaging structure.

[0040] Of course, the present invention does not limit the specific thickness of the dielectric layer 300, and specific changes can be made according to actual packaging product requirements.

[0041] Furthermore, the packaging structure in this embodiment also includes a first thermally conductive adhesive layer (not shown in the figure), which is arranged between the dielectric layer 300 and the substrate body 210 and is used to bond and fix the dielectric layer 300 to the surface of the substrate body 210 .

[0042] The first thermal conductive adhesive layer includes a conductive adhesive with high thermal conductivity and a non-conductive adhesive. The conductive adhesive can be made of conductive silver adhesive, solder paste, sintered silver, etc., and the non-conductive adhesive can be made of insulating resin with high thermal conductivity, etc.

[0043] Furthermore, the packaging structure in this embodiment also includes a second thermally conductive adhesive layer (not shown in the figure), which is arranged between the first element surface 110 and the dielectric layer 300, and is used to bond and fix the temperature detection element 100 to a side of the dielectric layer 300 away from the substrate body 210.

[0044] The second thermally conductive adhesive layer includes a conductive adhesive with high thermal conductivity and a non-conductive adhesive. The conductive adhesive can be made of conductive silver adhesive, solder paste, sintered silver, etc., and the non-conductive adhesive can be made of insulating resin with high thermal conductivity, etc.

[0045] Of course, the present invention does not limit the specific thickness of the first thermal conductive adhesive layer and the second thermal conductive adhesive layer, and the thickness can be adjusted according to the actual packaging process.

[0046] The packaging structure further includes a plastic package 400, which covers the temperature detection element 100, the substrate body 210, and a portion of the first lead 220 and a portion of the second lead 230 close to the substrate body 210. In other words, the plastic package 400 exposes a portion of the first lead 220 and the second lead 230 away from the substrate body 210, and the exposed portion of the lead is used to achieve electrical connection with an external circuit board or device.

[0047] Specifically, the plastic package body 400 is based on epoxy resin and is added with additives such as a curing agent and a coupling agent, so as to provide mechanical support and sealing protection for the packaging structure.

[0048] In this embodiment, the package structure further includes a metal bonding wire 500, which connects the pad 130 on the first component surface and the second lead 230 to achieve electrical connection between the temperature detection element 100 and the second lead 230. In the package structure, heat can be directly transferred to the first component surface 110, and the components on the first component surface 110 receive the heat information and generate signal changes. The signal information in the temperature detection element 100 is transferred to the second lead 230 through the metal bonding wire 500, and then transferred to the external circuit board or device by the second lead 230 for signal processing.

[0049] The metal bonding wire 500 includes but is not limited to gold wire, silver wire, copper wire, etc.

[0050] Specifically, the plastic package body 400 also covers the metal bonding wire 500 .

[0051] like Figure 2 , is a packaging method corresponding to the packaging structure in Embodiment 1, comprising:

[0052] S1: Provide a packaging substrate, which includes a substrate body, a first lead and a second lead.

[0053] S2: forming a dielectric layer on one side of the substrate body.

[0054] S3: providing a temperature detection element, the temperature detection element comprising a first element surface provided with a solder pad, forming the temperature detection element on a side of the dielectric layer away from the substrate body, and making the first element surface face the dielectric layer.

[0055] S4: Through a wire bonding process, the pad and the second lead are electrically connected via a metal bonding wire.

[0056] Of course, before step S2 , the method further includes: forming a first thermal conductive adhesive layer on a side surface of the substrate body.

[0057] Of course, before step S3 , the method further includes: forming a second thermal conductive adhesive layer on a side of the dielectric layer away from the substrate body.

[0058] Furthermore, this embodiment also includes step S5: providing a molding compound, so that the molding compound covers the temperature detection element, the metal bonding wire, the dielectric layer, the substrate body, and a portion of the first lead and the second lead close to the substrate body.

[0059] Example 2

[0060] like Figure 3 , which is a packaging structure provided in Example 2 of the utility model. Different from the packaging structure in Example 1, the temperature detection element 100 in Example 2 is fixed to the side of the dielectric layer 300 away from the substrate body 210 by metal ball welding, and the electrical connection between the pad on the first element surface and the second lead is realized by metal ball welding.

[0061] In this embodiment, the temperature sensing element 100 is not fixed to the side of the dielectric layer 300 away from the substrate body 210 by bonding through the second thermal conductive adhesive layer, but is fixed to the side of the dielectric layer 300 away from the substrate body 210 by welding through the metal solder balls 600.

[0062] Specifically, the dielectric layer 300 extends and connects the substrate body 210 and the surface of the second lead 230 facing the first element surface, and the temperature detection element 100 is disposed on a side of the dielectric layer 300 away from the substrate body 210 .

[0063] Specifically, the material of the dielectric layer 300 is still set to be a spacing dielectric, including but not limited to aluminum oxide ceramics, aluminum nitride ceramics, silicon nitride ceramics, and silicon carbide ceramics, that is, the temperature detection element 100 and the substrate body 210 are also electrically isolated by the dielectric layer 300.

[0064] However, in this embodiment, a metal circuit layer connecting the pad on the first component surface 110 and the second lead 230 is also provided in the dielectric layer 300. The electrical connection between the temperature detection element 100 and the second lead 230 is achieved by controlling the circuit direction of the metal circuit layer in the dielectric layer 300.

[0065] More specifically, a metal solder ball 600 is provided between the temperature detection element 100 and the dielectric layer 300, and the temperature detection element 100 is fixed to the side of the dielectric layer 300 away from the substrate body 210 by soldering through the metal solder ball 600. The metal solder ball 600 is also used to connect the pad on the first element surface 110 and the metal circuit layer in the dielectric layer 300. In the packaging structure, heat can be directly transferred to the surface of the first element surface 110, and the components on the first element surface 110 receive the heat information and generate signal changes. The signal information in the temperature detection element 100 is transmitted to the second lead 230 through the metal solder ball 600 and the metal circuit layer, and then transmitted to the external circuit board or device for signal processing by the second lead 230.

[0066] The metal solder balls 600 include but are not limited to metal balls such as solder balls and copper balls.

[0067] Furthermore, in this embodiment, the packaging structure further includes a third thermal conductive adhesive layer, which is disposed between the dielectric layer 300 and the second lead 230 and is used to bond and fix the dielectric layer 300 to the second lead 230 .

[0068] Of course, in this embodiment, the plastic package body 400 also covers the metal solder balls 600 and the third thermal conductive adhesive layer.

[0069] like Figure 4 , is a packaging method corresponding to the packaging structure in Embodiment 2, comprising:

[0070] S1: Provide a packaging substrate, which includes a substrate body, a first lead and a second lead.

[0071] S2: forming a dielectric layer on one side of the substrate body, and extending the dielectric layer to connect the substrate body and the second lead, wherein a metal circuit layer electrically connected to the second lead is disposed in the dielectric layer.

[0072] S3: providing a temperature detection element, wherein the temperature detection element comprises a first element surface provided with a solder pad, and manufacturing a metal solder ball at the solder pad.

[0073] S4: forming a temperature detection element on a side of the dielectric layer away from the substrate body through a metal solder ball, and electrically connecting the metal solder ball to the metal circuit layer in the dielectric layer.

[0074] Of course, before step S2 , the method further includes: forming a first thermal conductive adhesive layer on a side surface of the substrate body, and forming a third adhesive layer on a side surface of the second lead.

[0075] Furthermore, this embodiment also includes step S5: providing a molding compound, so that the molding compound covers the temperature detection element, the metal solder ball, the dielectric layer, the substrate body, and a portion of the first lead and the second lead close to the substrate body.

[0076] To summarize, the first component surface of the temperature detection element with a solder pad is arranged toward the main surface of the substrate, and the heat generated in the packaging structure can be directly transferred to the first component surface of the temperature detection element through the substrate. The circuit on the first component surface recognizes the temperature information and outputs a feedback signal. Compared with the packaging scheme in the prior art in which the first component surface is arranged with its back to the substrate surface, the time for the heat in the packaging structure to be transferred to the first component surface is short in the present application, which can shorten the response time of the temperature detection element and improve the sensitivity of the temperature detection element.

[0077] It should be understood that although this specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each implementation mode may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

[0078] The series of detailed descriptions listed above are only specific descriptions of feasible implementation methods of the utility model. They are not intended to limit the protection scope of the utility model. Any equivalent implementation methods or changes that do not deviate from the technical spirit of the utility model should be included in the protection scope of the utility model.

Claims

1. A packaging structure, characterized in that: It comprises a temperature detection element and a packaging substrate; the temperature detection element comprises a first component surface and a second component surface opposite to each other, and the first component surface is provided with a pad; the packaging substrate comprises: A substrate body, arranged on one side of the first element surface of the temperature detection element; A first lead connected to the substrate body; The second lead is electrically connected to the pad.

2. The packaging structure according to claim 1, characterized in that: A dielectric layer is also included, and the dielectric layer is arranged between the first element surface and the substrate body.

3. The packaging structure according to claim 2, characterized in that: The thermal conductivity of the dielectric layer is greater than 10 W / mK.

4. The packaging structure according to claim 2, characterized in that: It also includes a first thermally conductive adhesive layer, which is arranged between the dielectric layer and the substrate body and is used to bond and fix the dielectric layer to the surface of the substrate body.

5. The packaging structure according to claim 2, characterized in that: It also includes a second thermally conductive adhesive layer, which is arranged between the first element surface and the dielectric layer and is used to bond and fix the temperature detection element to a side surface of the dielectric layer away from the substrate body.

6. The packaging structure according to claim 1, characterized in that: It also includes a plastic package, which covers the temperature detection element, the substrate body, and a portion of the first lead and a portion of the second lead close to the substrate body.

7. The packaging structure according to claim 1, characterized in that: Also included is a metal bonding wire, wherein the metal bonding wire connects the bonding pad and the second lead.

8. The packaging structure according to claim 2, characterized in that: The dielectric layer extends and connects the substrate body and the surface of the second lead facing the first element surface, and the temperature detection element is arranged on the side of the dielectric layer away from the substrate body; A metal circuit layer connecting the pad and the second lead is disposed in the dielectric layer.

9. The packaging structure according to claim 8, characterized in that: A metal solder ball is arranged between the temperature detection element and the dielectric layer, and is used to fix the temperature detection element to the side of the dielectric layer away from the substrate body, and to connect the solder pad and the metal circuit layer.

10. The packaging structure according to claim 8, characterized in that: It also includes a third thermally conductive adhesive layer, which is disposed between the dielectric layer and the second lead and is used to bond and fix the dielectric layer to the second lead.

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