CN218918900U

CN218918900U - Optical sensor packaging structure

Info

Publication number: CN218918900U
Application number: CN202223017177.1U
Authority: CN
Inventors: 请求不公布姓名
Original assignee: Shenzhen Xhorse Electronics Co Ltd
Current assignee: Shenzhen Xhorse Electronics Co Ltd
Priority date: 2022-11-14
Filing date: 2022-11-14
Publication date: 2023-04-25
Anticipated expiration: 2032-11-14

Abstract

The utility model provides an optical sensor packaging structure, which relates to the technical field of chip packaging and comprises a substrate, an optical sensor wafer and packaging colloid. The upper surface of the substrate is provided with a plurality of welding spots, the lower surface of the substrate is provided with pins with the same quantity as the welding spots, and the welding spots and the pins are connected in the substrate in a one-to-one correspondence manner. The optical sensor wafer is arranged on the substrate and is connected with the welding spots through wires. The packaging colloid covers the optical sensor wafer and the substrate, and is stepped and comprises a first-order colloid and a second-order colloid; the first-order colloid covers the optical sensor wafer and the welding spots, and the second-order colloid covers the rest part of the substrate; the first order colloid has a higher height than the second order colloid. The thickness of the packaging colloid around the substrate is reduced through the step-shaped packaging colloid, edge breakage can be prevented when cutting is conducted, and the glue consumption is reduced.

Description

Optical sensor packaging structure

Technical Field

The utility model relates to the technical field of chip packaging, in particular to an optical sensor packaging structure.

Background

Along with the development of technology, the updating iteration speed of electronic products is continuously accelerated, and the optical sensor is also developed towards miniaturization and integration, so that new demands are put on the packaging of the optical sensor. The current common packaging mode of the optical sensor is adhesive fixing, a copper substrate is used as a carrier, and a sensor wafer is covered above the copper substrate by resin and the component is protected. At present, when an optical sensor chip is packaged, a wafer and a substrate are wrapped into a cuboid with consistent thickness through resin, and the packaging mode can enable the resin on the substrate on the side face of the wafer to be thicker, so that edge breakage is easy to occur during cutting.

Disclosure of Invention

In order to solve the above technical problems, the present utility model provides an optical sensor package structure, including: the upper surface of base plate is provided with a plurality of solder joints, and the lower surface of base plate is provided with the pin the same with solder joint quantity, and solder joint and pin are connected in the base plate one-to-one.

And the optical sensor wafer is arranged on the substrate and is connected with the welding spots through wires.

The packaging colloid covers the optical sensor wafer and the substrate, and is in a ladder shape and comprises a first-order colloid and a second-order colloid; the first-order colloid covers the optical sensor wafer and the welding spots, and the second-order colloid covers the rest part of the substrate; the first order colloid has a higher height than the second order colloid.

The optical sensor packaging structure has the beneficial effects that the thickness of the packaging colloid at the periphery of the substrate can be reduced through the stepped packaging colloid, the problem of edge breakage during cutting is prevented, the use of packaging colloid materials is reduced, and the cost is saved.

Drawings

FIG. 1 is a schematic structural diagram of embodiment 1 of the present utility model;

FIG. 2 is a top view of embodiment 1 of the present utility model;

FIG. 3 is a bottom view of embodiment 1 of the present utility model;

FIG. 4 isbase:Sub>A cross-sectional view of portion A-A of FIG. 2 in accordance with the present utility model.

Wherein, 1: a substrate; 2: welding spots; 3: pins; 4: an optical sensor die; 5: a wire; 6: packaging colloid; 61: a first order colloid; 62: and a second-order colloid.

Detailed Description

It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the utility model.

The following description of the embodiments of the present utility model will be made clearly and fully with reference to the accompanying drawings, in which it is evident that the embodiments described are only some, but not all embodiments of the utility model. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without any inventive effort, are intended to be within the scope of the utility model.

It should be noted that, in the embodiments of the present utility model, all directional indicators (such as up, down, left, right, front, and rear … …) are merely used to explain the relative positional relationship, movement conditions, and the like between the components in a specific posture (as shown in the drawings), if the specific posture is changed, the directional indicators correspondingly change, and the connection may be a direct connection or an indirect connection.

Furthermore, descriptions such as those referred to as "first," "second," and the like, are provided for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implying an order of magnitude of the indicated technical features in the present disclosure. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In addition, the technical solutions of the embodiments may be combined with each other, but it is necessary to base that the technical solutions can be realized by those skilled in the art, and when the technical solutions are contradictory or cannot be realized, the combination of the technical solutions should be considered to be absent and not within the scope of protection claimed in the present utility model.

Example 1

As shown in fig. 1 to 4, embodiment 1 of the present application provides an optical sensor package structure, which includes a substrate 1, an optical sensor die 4 and an encapsulant 6, wherein the encapsulant 6 is indicated by a dotted line. The upper surface of the substrate 1 is provided with a plurality of welding spots 2, the lower surface of the substrate 1 is provided with pins 3 with the same quantity as the welding spots 2, and the welding spots 2 and the pins 3 are connected in the substrate 1 in a one-to-one correspondence manner. The substrate 1 includes, but is not limited to, a resin substrate, an aluminum substrate or a sapphire substrate, and the optical sensor chip has a high requirement on the flatness of the substrate 1, and the substrate 1 is preferably a ceramic substrate.

An optical sensor die 4 is disposed on the substrate 1 and connected to the pads 2 by wires 5. In order to ensure the detection accuracy of the optical sensor wafer 4, the optical sensor wafer 4 has high requirements on the plane flatness of the substrate 1, the light transmittance of the encapsulation colloid 6 and the cleaning degree. The optical sensor die 4 is preferably fixedly disposed at a central position of the upper surface of the substrate 1, and the positions of the pads 2 of the upper surface of the substrate 1 may be arranged according to the optical sensor die 4.

The packaging colloid 6 covers the optical sensor wafer 4 and the substrate 1, and the packaging colloid 6 is in a step shape and comprises a first-order colloid 61 and a second-order colloid 62; the first step of colloid 61 covers the optical sensor wafer 4 and the welding spots 2, and the second step of colloid 62 covers the rest part of the substrate 1; the first stage colloid 61 is higher in height than the second stage colloid 62.

The encapsulant 6 is a light-transmitting encapsulant, preferably a high-light-transmittance encapsulant, and further preferably the light-transmitting encapsulant has a light transmittance of 85% or more. The higher the light transmittance of the encapsulant 6, the more light the optical sensor die 4 can receive and the higher the sensitivity.

The thickness of the second-order colloid 62 around the substrate 1 after encapsulation is smaller, and the edge is not easy to collapse during cutting, so that the quality of chips can be improved. The first-order colloid 61 covered on the optical sensor wafer 4 and the welding spot 2 can cover the connected lead 5 at the same time, thereby playing a good role in protection. And compared with a whole-piece packaging structure in which the optical sensor wafer 4 and the substrate 1 are wrapped into a cuboid with consistent thickness, the packaging structure provided by the embodiment can reduce the use of materials of the packaging colloid 6 and reduce the production cost.

In this embodiment, the first-stage colloid 61 and the second-stage colloid 62 of the stepped encapsulation colloid 6 are integrally formed, and can be realized by a mold, and in the production process, a plurality of optical sensor wafers 4 are fixed on a monolithic substrate 1, and then wire bonding is performed, at this time, the spacing between the optical sensor wafers 4 on the monolithic substrate 1 is wider, and cleaning is easily performed by means of plasma and the like, so that the cleanliness of the optical sensor chip is ensured. After cleaning, the whole substrate 1 is reversely pressed into a mold filled with the packaging colloid 6, and after the packaging colloid 6 is hardened and demoulded, cutting is carried out, and each obtained optical sensor chip is provided with the stepped packaging colloid 6. The stepped packaging colloid 6 is manufactured through the integral molding of the die, so that the manufacturing time can be shortened, the quality of the packaging colloid 6 is improved, and the packaging colloid is filled after the enclosure is not required to be additionally arranged on the substrate, so that the substrate is easier to clean.

The optical sensor packaging structure provided by the embodiment can reduce the thickness of the packaging colloid 6 around the substrate 1 through the stepped packaging colloid 6, prevent the problem of edge breakage during cutting, reduce the use of packaging colloid materials and save the cost.

Example 2

In this embodiment, the encapsulant 6 is silica gel according to a further modification of embodiment 1. Wherein, silica gel represents an organic silicon material with a main chain of Si-O-Si bond, and a side chain of the organic silicon material can be connected with different functional groups. The organic silicon material has excellent heat stability and weather resistance, wide working temperature range, good hydrophobicity and extremely weak hygroscopicity, and can effectively prevent solution and moisture from invading the inside, thereby prolonging the service life of the chip. The organic silicon material has the advantage of high light transmittance, the light transmittance can reach 95%, the performance is obviously better than that of epoxy resin, and the organic silicon material is an ideal optical sensor packaging material.

In this embodiment, the substrate 1 is a ceramic substrate, and compared with other types of substrates 1, the surface flatness of the ceramic substrate is high, so as to meet the mounting requirement of the optical sensor wafer 4. The ceramic substrate also has high thermal conductivity, so that the heat dissipation performance is excellent and the reliability is high.

In this embodiment, the thermal expansion coefficient of the ceramic substrate is low and is close to that of the chip, and the packaging colloid 6 is silica gel with certain flexibility, so that when the substrate 1 and the chip expand or contract, the stress generated by the packaging colloid 6 on the substrate 1 or the chip is small, the internal stress of the packaging structure of the optical sensor is reduced, thereby improving the cracking problem and the long-term reliability of the chip.

The thickness of the first stage gel 61 and the second stage gel 62 of the encapsulant 6, which represents the distance from the surface of the encapsulant 6 to the upper surface of the optical sensor wafer 4 or to the upper surface of the substrate 1, may be the same or different. The distance from the highest point of the first-order colloid 61 to the upper surface of the optical sensor wafer 4 is greater than or equal to 30% of the thickness of the optical sensor wafer 4 and less than or equal to 2 times the thickness of the optical sensor wafer 4. When the thickness of the first-order colloid 61 is too thin, the optical sensor wafer 4 and the solder joint 2 cannot be effectively protected; when the thickness of the first-stage colloid 61 is too thick, the light transmittance of the first-stage colloid 61 is reduced, and the material is wasted. The upper surface of the first-stage colloid 61 above the optical sensor wafer 4 is a flat surface, and the flatness of the flat surface is 35 μm. The flat surface can reduce energy loss when light passes through the first-order colloid 61, and improve the detection accuracy of the optical sensor wafer 4.

The distance from the highest point of the second-stage colloid 62 to the upper surface of the substrate 1 is less than or equal to 0.1 mm. The thinner the second encapsulant 62 is, the less susceptible to edge chipping during dicing, thereby enabling further improvement in package quality.

According to the optical sensor packaging structure provided by the embodiment, the performances of light transmittance, heat dissipation, stability and the like of the optical sensor packaging structure are further improved through the packaging colloid 6 formed by silica gel and the ceramic substrate, the internal stress of a chip is reduced, the cracking problem of the chip is improved, and the service life of the chip is prolonged.

The foregoing description is only of the preferred embodiments of the present utility model and is not intended to limit the scope of the utility model, and all equivalent structures or equivalent processes using the descriptions and drawings of the present utility model or directly or indirectly applied to other related technical fields are included in the scope of the utility model.

Claims

1. An optical sensor package structure, comprising:

the device comprises a substrate (1), wherein a plurality of welding spots (2) are arranged on the upper surface of the substrate (1), pins (3) with the same number as the welding spots (2) are arranged on the lower surface of the substrate (1), and the welding spots (2) and the pins (3) are connected in a one-to-one correspondence in the substrate (1); an optical sensor wafer (4) arranged on the substrate (1) and connected with the welding spots (2) through leads (5);

an encapsulation colloid (6) covering the optical sensor wafer (4) and the substrate (1), wherein the encapsulation colloid (6) is in a step shape and comprises a first-order colloid (61) and a second-order colloid (62); the first-order colloid (61) covers the optical sensor wafer (4) and the welding spots (2), and the second-order colloid (62) covers the rest part of the substrate (1); the first order colloid (61) has a height higher than the second order colloid (62).

2. The optical sensor package according to claim 1, wherein the first-stage colloid (61) and the second-stage colloid (62) are integrally formed.

3. The optical sensor package according to claim 1, wherein the encapsulant (6) is a light transmissive encapsulant.

4. An optical sensor package according to claim 3, characterized in that the encapsulant (6) is a silicone gel.

5. The optical sensor package structure according to claim 1, wherein a distance from a highest point of the first-order colloid (61) to an upper surface of the optical sensor die (4) is greater than or equal to 30% of a thickness of the optical sensor die (4) and less than or equal to 2 times the thickness of the optical sensor die (4).

6. The optical sensor package according to claim 1, wherein the distance from the highest point of the second-stage colloid (62) to the upper surface of the substrate (1) is less than or equal to 0.1 mm.

7. The optical sensor package according to claim 1, wherein the upper surface of the first-order encapsulant (61) above the optical sensor die (4) is a flat surface, and the flatness of the flat surface is 35 μm.

8. The optical sensor package according to claim 1, wherein the substrate (1) is a ceramic substrate.