CN-115621833-B - Laser semiconductor chip packaging structure, packaging method and electronic equipment

CN115621833BCN 115621833 BCN115621833 BCN 115621833BCN-115621833-B

Abstract

The embodiment of the application provides a laser semiconductor chip packaging structure, a packaging method and electronic equipment, and relates to the technical field of packaging processes. In the packaging structure, a first substrate is provided with a through hole, the heights of a laser semiconductor chip and a lead arranged in the through hole of the first substrate and on a second substrate are not more than the upper surface of the first substrate, and optical cement is filled in the through hole of the first substrate. By means of the space formed in the through hole of the first substrate, the laser semiconductor chip and the lead are accommodated, and the highest point of the lead after the lead bonding is still lower than the upper surface of the substrate, so that screen printing, component mounting and reflow soldering are not affected, and the lead bonding can be performed first and then the reflow soldering can be performed, and the influence of brazing flux residues on the lead bonding process after the reflow soldering is avoided.

Inventors

QIN HONGBO
FU ZHAOSEN
ZHOU YIFAN
Wei Shengqin

Assignees

广州导远电子科技有限公司

Dates

Publication Date: 20260505
Application Date: 20220908

Claims (11)

1. The laser semiconductor chip packaging structure is characterized by comprising a substrate and optical cement (12), wherein the substrate comprises a first substrate (1) and a second substrate (2), and the first substrate (1) and the second substrate (2) are stacked from top to bottom; The first substrate (1) is provided with a through hole, a laser semiconductor chip (6), a lead (7) and a conduction band bonding pad (4) are arranged in the through hole of the first substrate (1) and on the second substrate (2), the laser semiconductor chip (6) is connected with the conduction band bonding pad (4) through the lead (7), and the heights of the laser semiconductor chip (6) and the lead (7) are not more than the upper surface of the first substrate (1); The substrate further comprises a third substrate (3), wherein the first substrate (1), the second substrate (2) and the third substrate (3) are stacked from top to bottom, and the second substrate (2) is provided with a through hole; The orthographic projection of the upper surface of the first substrate (1) of the through hole of the second substrate (2) is within the orthographic projection range of the upper surface of the first substrate (1) of the through hole of the first substrate (1); the upper surface of the light reflecting piece (11) is higher than the upper surface of the first substrate (1), and the upper surface of the optical adhesive (12) is flush with the upper surface of the first substrate (1).
2. The packaging structure according to claim 1, characterized in that in the through-hole of the first substrate (1) and on the second substrate (2) there is further provided an adhesive pad (4 '), to which adhesive pad (4') the laser semiconductor chip (6) is connected.
3. The packaging structure according to claim 2, characterized in that the packaging structure further comprises a conductive silver paste (5), the laser semiconductor chip (6) being connected to the bonding pad (4') by means of the conductive silver paste (5).
4. The package structure according to claim 2, wherein the laser semiconductor chip (6), the lead (7), the conduction band pad (4) and the bonding pad (4') each comprise two groups, the two groups of laser semiconductor chips (6), lead (7) and conduction band pad (4) being arranged axisymmetrically.
5. The package structure according to claim 4, wherein the two sets of laser semiconductor chips (6), leads (7) and conduction band pads (4) are arranged sequentially from inside to outside of the symmetry axis.
6. The packaging structure according to claim 1, characterized in that an electronic component is provided on the first substrate (1), the electronic component comprising a resistor (8), a capacitor (9) and a printed matter, the resistor (8) and the capacitor (9) being electrically connected by the printed matter.
7. An electronic device comprising the laser semiconductor chip package structure of any one of claims 1-6.
8. A method of packaging a laser semiconductor chip, comprising: Casting with AlN green ceramic chips to obtain a first substrate green ceramic chip and a second substrate green ceramic chip, wherein through holes are formed in the first substrate green ceramic chip; The ceramic substrate is obtained by pressing and sintering the first substrate green ceramic chip and the second substrate green ceramic chip, and comprises a first substrate (1) formed by the first substrate green ceramic chip and a second substrate (2) formed by the second substrate green ceramic chip; -mounting a conduction band pad (4) and a laser semiconductor chip (6) in a through hole of the first substrate (1) and on the second substrate (2); forming a lead (7) between the conduction band bonding pad (4) and the laser semiconductor chip (6) through a wire bonding technology, wherein the heights of the laser semiconductor chip (6) and the lead (7) are not more than the upper surface of the first substrate (1); filling optical cement (12) in the through hole of the first substrate (1); the method further comprises the steps of casting AlN green ceramic chips to obtain third substrate green ceramic chips, and arranging through holes on the second substrate green ceramic chips; The step of sintering the first substrate green ceramic chip and the second substrate green ceramic chip under pressure comprises the step of sintering the first substrate green ceramic chip, the second substrate green ceramic chip and the third substrate green ceramic chip under pressure, wherein the ceramic substrate further comprises a third substrate (3) formed by sintering the third substrate green ceramic chip under pressure, and the first substrate (1), the second substrate (2) and the third substrate (3) are stacked from top to bottom; The method further comprises mounting a reflector (11) in the through hole of the second substrate (2) and on the third substrate (3); The orthographic projection of the upper surface of the first substrate (1) of the through hole of the second substrate (2) is within the orthographic projection range of the upper surface of the first substrate (1) of the through hole of the first substrate (1); the upper surface of the light reflecting piece (11) is higher than the upper surface of the first substrate (1), and the upper surface of the optical adhesive (12) is flush with the upper surface of the first substrate (1).
9. The method according to claim 8, wherein the step of mounting the conduction band pad (4) and the laser semiconductor chip (6) in the through hole of the first substrate (1) and on the second substrate (2) comprises: In the through-holes of the first substrate (1) and on the second substrate (2), bonding pads (4 ') are made and a laser semiconductor chip (6) is bonded to the bonding pads (4') with a conductive silver paste.
10. The method according to claim 8, further comprising printing a screen and solder paste on the first substrate (1), and surface mounting the resistor (8), the capacitor (9) and the device (10) by an SMT mounter.
11. The method according to claim 10, further comprising reflow soldering the resistor (8), the capacitor (9), the device (10) and the first substrate (1).

Description

Laser semiconductor chip packaging structure, packaging method and electronic equipment Technical Field The present application relates to the field of packaging technologies, and in particular, to a laser semiconductor chip packaging structure, a packaging method, and an electronic device. Background Along with the application development of the high-power semiconductor laser, for example, the application is continuously expanded in the field of automatic driving of vehicles, and the characteristics of complex operation under vehicle-mounted working conditions, long life cycle of vehicle-mounted products and the like are considered, so that higher requirements are put on the packaging quality of laser semiconductor chips and modules. At present, the semiconductor laser and the semiconductor chip commonly used in the market all need a wire bonding method to be electrically and signally connected with the outside. During the production process, the surface of a printed board (Printed Circuit Board, PCB) or a substrate is required to be subjected to screen printing with solder paste, and then the required components are subjected to surface mounting and reflow soldering. Screen printing requires that the surface of the PCB or substrate be flat, and therefore wire bonding cannot be performed on the surface of the PCB or substrate prior to screen printing, which is typically performed by screen printing solder paste, mounting components, and reflow soldering followed by wire bonding. However, the solder paste contains soldering flux or soldering flux, and volatilization and residue of the soldering flux or soldering flux exist in the process of reflow soldering, so that the lead bonding area is polluted, the lead bonding reject ratio is high, and the problem of poor reliability easily occurs. In addition, in terms of structure, in the scheme commonly used in the market at present, a metal or plastic shell is generally adopted for protecting the laser semiconductor chip, and an optical glue is encapsulated for protecting the laser semiconductor chip. On one hand, the method can lead to the generation of an additional packaging process, so that the production cost is increased, and on the other hand, due to the difference of material properties, new reliability problems such as delamination, cracking and the like are easy to generate between the metal or plastic shell and the substrate under the working conditions such as thermal shock, thermal circulation, random vibration and the like. Therefore, how to package a laser semiconductor chip reliably is a technical problem to be solved. Disclosure of Invention The application aims to provide a laser semiconductor chip packaging structure, electronic equipment and a laser semiconductor chip packaging method, which are used for solving the technical problem of how to reliably package a laser semiconductor chip in the prior art. In order to achieve the above purpose, the following technical scheme is adopted in the embodiment of the application. In a first aspect, an embodiment of the present application provides a laser semiconductor chip package structure, including a substrate and an optical adhesive, where the substrate includes a first substrate and a second substrate, and the first substrate and the second substrate are stacked from top to bottom. The laser semiconductor chip is connected with the conduction band pad through the lead, the heights of the laser semiconductor chip and the lead do not exceed the upper surface of the first substrate, and the through hole of the first substrate is filled with optical cement. Optionally, in the through hole of the first substrate and on the second substrate, an adhesive pad is further provided, and the laser semiconductor chip is connected to the adhesive pad. Optionally, the package structure further comprises conductive silver paste, and the laser semiconductor chip is connected to the bonding pad through the conductive silver paste. Optionally, the laser semiconductor chip, the lead, the conduction band pad and the bonding pad comprise two groups, and the two groups are axisymmetrically arranged. Alternatively, the two groups of laser semiconductor chips, the leads and the conduction band pads are sequentially arranged from inside to outside from the symmetry axis. Optionally, the substrate further comprises a third substrate, the first substrate, the second substrate and the third substrate are stacked from top to bottom, the second substrate is provided with a through hole, and the light reflecting piece is arranged in the through hole of the second substrate and on the third substrate. Optionally, the orthographic projection of the upper surface of the first substrate of the through hole of the second substrate is within the orthographic projection range of the upper surface of the first substrate of the through hole of the first substrate. Optionally, the upper surface of the light reflecting member is higher th