Sensor and preparation method thereof

Abstract

The invention relates to the technical field of sensors, and discloses a sensor which comprises a substrate, a wafer, an epoxy resin mold and a cover plate, the wafer is arranged on the substrate and fixedly connected with the substrate, the epoxy resin mold covers the wafer, the cover plate is arranged at the top of the substrate and matched with the substrate to wrap the wafer, and one side, facing the wafer, of the cover plate is provided with a metal coating. Compared with the prior art, a common LCP cover plate is replaced by the cover plate with EMI shielding, so that the influence of external interference on the sensor and the interference of the sensor on other external parts can be effectively reduced while the structural strength of the cover plate is improved. The invention also provides a preparation method of the sensor. The preparation method has the advantages of simple process, easiness in implementation and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of sensors, and in particular to a sensor and a preparation method thereof. Background Art

[0002] Ambient light sensors, spectral sensors, proximity sensors, etc. are widely used in consumer electronics, industrial automation, automotive electronics, and medical electronics. They are generally composed of a projector, a light receiver, an integrated circuit, an output circuit, etc.

[0003] These sensors use covers made of LCP or PA materials to protect the sensors and shield internal optical signal interference. However, LCP or PA materials can only shield optical signals and cannot effectively shield external electromagnetic interference. In addition, covers made of LCP or PA materials are relatively soft and are prone to scratches and deformation. Summary of the invention

[0004] The object of the present invention is to provide a sensor with high structural strength and excellent shielding effect.

[0005] In order to achieve the above object, the present invention provides a sensor, which includes:

[0006] substrate;

[0007] A chip, disposed on the top of the substrate and fixedly connected to the substrate;

[0008] The cover plate is arranged on the top of the substrate and cooperates with the substrate to cover the chip. The side of the cover plate facing the chip has a metal coating.

[0009] In some embodiments of the present application, further comprising:

[0010] The epoxy resin mold is arranged on the top of the substrate and fills the gap between the substrate and the cover plate to protect the wafer.

[0011] Another object of the present application is to provide a sensor preparation method, which comprises the following steps:

[0012] S1. Place a substrate on a workbench and place a wafer on the substrate;

[0013] S2, arranging cables on the substrate pad and the chip pad to make the chip and the substrate conductive;

[0014] S3, providing a metal coating on the inner surface of the cover plate;

[0015] S4, placing a cover plate on the substrate and fixedly connecting the cover plate to the substrate, wherein the cover plate cooperates with the substrate to shield the wafer;

[0016] S5, cutting the base plate and the cover plate to form a plurality of independent finished blocks;

[0017] S6. Continue to set a metal coating on the outside of each finished block to enhance the shielding effect.

[0018] In some embodiments of the present application, the following steps are further included between step S3 and step S4:

[0019] S301, setting an epoxy resin mold on the top of the substrate to protect the chip and the cable;

[0020] S302, cutting the substrate with the epoxy resin mold to form an assembly groove for setting the top cover.

[0021] The present invention provides a sensor, which has the following advantages compared with the prior art:

[0022] The present application provides a cover plate with EMI shielding capability by providing a metal coating. That is, based on the traditional optical sensor packaging structure, the present application replaces the ordinary LCP cover plate with a cover plate with EMI shielding. The sensor with the EMI shielding cover plate has higher stability and can effectively reduce the impact of external interference on the sensor, or reduce its own interference with other external parts; further, non-shielded sensors are more sensitive to environmental changes and interfering electromagnetic waves. The sensor top cover of the present application is provided with a shielding layer, which can improve the sensing accuracy, reduce the errors caused by external interference, and adapt to some occasions with higher requirements for sensor accuracy and stability.

[0023] The present invention also provides a method for preparing the sensor, which has the advantages of simple process and easy implementation. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A schematic diagram of the structure of a sensor according to some embodiments of the present invention;

[0025] Figure 2 Schematic diagram of the process of preparing the sensor of the present invention

[0026] Figure 3 It is a schematic diagram of the state of the sensor in step S2 of the present invention;

[0027] Figure 4 It is a schematic diagram of the state of the sensor in step S4 of the present invention;

[0028] Figure 5 It is a schematic diagram of the state of the sensor in step S5 of the present invention;

[0029] Figure 6 It is a schematic diagram of the state of the sensor in step S6 of the present invention;

[0030] Figure 7 It is a schematic diagram of the state of the sensor in step S7 of the present invention.

[0031] In the figure: 1. substrate; 2. chip; 3. cover plate; 4. epoxy resin mold. DETAILED DESCRIPTION

[0032] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0033] It should be understood that the terms "first" and "second" are only used for descriptive purposes to distinguish technical features of the same type, and should not be understood as indicating or implying the relative importance, order, and quantity of these technical features, that is, the "first" technical feature can be called the "second" technical feature, the "second" technical feature can also be called the "first" technical feature, and the technical features defined as "first" and "second" can explicitly or implicitly include one or more of the technical features. In addition, unless otherwise specified, the meaning of "plurality" is two or more.

[0034] It should be emphasized that in the description of this application, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0035] See also Figures 1 to 7The embodiment of the present invention provides a sensor, which includes a substrate 1, a chip 2 and a cover plate 3. The chip 2 is arranged on the substrate 1 and fixedly connected thereto. The cover plate 3 is arranged on the top of the substrate 1 and cooperates with the substrate 1 to cover the chip 2. The cover plate 3 has a metal coating on the side facing the chip 2. Based on the above structure, the provision of the metal coating enables the cover plate 3 to have EMI shielding capability, that is, on the basis of the traditional optical sensor packaging structure, the present application replaces the ordinary LCP cover plate 3 with a cover plate 3 with EMI shielding. The sensor with the EMI shielding cover plate 3 has higher stability and can effectively reduce the impact of external interference on the sensor, or reduce its own interference with other external parts; further, the non-shielded sensor is more sensitive to environmental changes and interfering electromagnetic waves. The sensor top cover of the present application is provided with a shielding layer, which can improve the sensing accuracy, reduce the error caused by external interference, and adapt to some occasions with higher requirements for sensor accuracy and stability.

[0036] Optionally, in some embodiments of the present application, the sensor further includes an epoxy resin mold 4, which is disposed on the top of the substrate 1 and fills the gap between the substrate 1 and the cover plate 3 to protect the chip 2. The epoxy resin mold 4 can cover the chip 2 and the cable before the cover plate 3, thereby achieving a protective effect on the chip 2.

[0037] Based on the above sensor, the present application also provides a method for preparing the sensor, which specifically comprises the following steps:

[0038] S1, placing a substrate 1 on a workbench, and placing a wafer 2 on the substrate 1;

[0039] S2, setting cables on the pads of substrate 1 and wafer 2 to make wafer 2 and substrate 1 conductive;

[0040] S3, providing a metal coating on the inner surface of the cover plate 3;

[0041] S4, setting an epoxy resin mold 4 on the top of the substrate 1 to protect the chip 2 and the cable;

[0042] S5, cutting the substrate 1 with the epoxy resin mold 4 to form an assembly groove for setting the top cover.

[0043] S6, placing the cover plate 3 on the substrate 1 and fixedly connecting it to the substrate 1, the cover plate 3 cooperates with the substrate 1 to shield the wafer 2;

[0044] S7, cutting the substrate 1 and the cover plate 3 to form a plurality of independent finished blocks;

[0045] S8. Continue to set a metal coating on the outside of each finished block to enhance the shielding effect.

[0046] In summary, the present application provides a sensor, which includes a substrate 1, a wafer 2, an epoxy resin mold 4 and a cover plate 3. The wafer 2 is arranged on the substrate 1 and fixedly connected thereto, the epoxy resin mold 4 covers the wafer 2, the cover plate 3 is arranged on the top of the substrate 1 and cooperates with the substrate 1 to cover the wafer 2, and the cover plate 3 has a metal coating on the side facing the wafer 2. Compared with the prior art, the present application replaces the ordinary LCP cover plate 3 with a cover plate 3 with EMI shielding, which improves the structural strength of the cover plate 3 and can effectively reduce the impact of external interference on the sensor and its own interference with other external parts.

[0047] The present invention also provides a method for preparing the sensor, which has the advantages of simple process and easy implementation.

[0048] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and substitutions can be made without departing from the technical principles of the present invention. These improvements and substitutions should also be regarded as the scope of protection of the present invention.

Claims

1. A sensor, characterized in that: include: base(1); A chip (2) is arranged on the top of the substrate (1) and is fixedly connected to the substrate (1); A cover plate (3) is arranged on the top of the substrate (1) and cooperates with the substrate (1) to cover the chip (2); the side of the cover plate (3) facing the chip (2) has a metal coating.

2. The sensor according to claim 1, characterized in that Also includes: An epoxy resin mold (4) is arranged on the top of the substrate (1) and fills the gap between the substrate (1) and the cover plate (3) to protect the chip (2).

3. A method for preparing a sensor, for preparing the sensor according to any one of claims 1 to 2, characterized in that: The steps include: S1, placing a substrate (1) on a workbench, and placing a wafer (2) on the substrate (1); S2, arranging cables on the soldering pads of the substrate (1) and the soldering pads of the chip (2) to make the chip (2) and the substrate (1) conductive; S3, providing a metal coating on the inner surface of the cover plate (3); S4, placing the cover plate (3) on the substrate (1) and fixedly connecting the cover plate (3) to the substrate (1), wherein the cover plate (3) cooperates with the substrate (1) to shield the wafer (2); S5, cutting the base plate (1) and the cover plate (3) to form a plurality of independent finished blocks; S6. Continue to set a metal coating on the outside of each finished block to enhance the shielding effect.

4. The sensor preparation method according to claim 3, characterized in that: The following steps are also included between step S3 and step S4: S301, placing an epoxy resin mold (4) on the top of the substrate (1) to protect the chip (2) and the cable; S302, cutting the substrate (1) with the epoxy resin mold (4) to form an assembly groove for setting the top cover.

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