WO2021072752A1

WO2021072752A1 - Laser diode encapsulation module, distance detection apparatus, and electronic device

Info

Publication number: WO2021072752A1
Application number: PCT/CN2019/111976
Authority: WO
Inventors: 罗飞宇; 吴佩欣; 詹亮
Original assignee: 深圳市大疆创新科技有限公司
Priority date: 2019-10-18
Filing date: 2019-10-18
Publication date: 2021-04-22
Also published as: CN113079708A

Abstract

A laser diode encapsulation module, a distance detection apparatus, and an electronic device. Said encapsulation module comprises: a substrate (300), having a first surface (30) and a second surface (32) opposite each other; a cover body, provided on the first surface (30) of the substrate (300), an accommodating space being formed between the substrate (300) and the cover body; a laser diode die (303), provided in the accommodating space and directly provided on the first surface (30) of the substrate (300); and an optical element, provided on the first surface (30) of the substrate (300); and a distance between the laser diode die (303) and the optical element is configured to enable emitted light of the laser diode die (303) to be emitted from the cover body after a light path thereof is changed by the optical element. The laser diode encapsulation module can implement not only the effect of improving the light emission efficiency of PLD chips, but also the use of array encapsulation of the plurality of PLD chips.

Description

Laser diode package module and distance detection device, electronic equipment

Manual

Technical field

The present invention generally relates to the field of integrated circuits, and more specifically to a laser diode packaging module, a distance detection device, and electronic equipment.

Background technique

Semiconductor lasers are a type of lasers that mature earlier and are developing rapidly. Because of its wide wavelength range, simple production, low cost, easy mass production, and because of its small size, light weight, and long life, its variety develops quickly and its application wide range.

The most widely used semiconductor lasers are Edge Emitting Lasers (EELs). The laser diode chip (Laser diode) of the side-emitting laser is generally long and narrow. The light-emitting surface is the smallest surface of the chip, and the two largest surfaces of the chip are metalized surfaces, which are external electrical connection points.

As for packaging, to ensure vertical light emission, metal TO packaging is generally used. TO packaging technology refers to a transistor outline or through-hole packaging technology, that is, a fully enclosed packaging technology.

The current laser diode chip packaging has the following problems:

1. The package size is large and the parasitic inductance is too large to generate narrow pulses, and cannot achieve the expected light extraction efficiency.

2. The process is more complicated, and it is not easy to realize multiple PLD chip package level arrays.

Therefore, in order to solve the above technical problems, it is necessary to improve the current laser packaging.

Summary of the invention

The present invention is proposed in order to solve at least one of the above-mentioned problems. The present invention provides a laser diode package module, which can improve the problem of large parasitic inductance existing in the current TO package, and can overcome the problems described above.

Specifically, one aspect of the present invention provides a laser diode packaging module, the packaging module comprising:

The substrate has a first surface and a second surface opposite to each other;

A cover body is arranged on the first surface of the substrate, and an accommodation space is formed between the substrate and the cover body;

The laser diode chip is arranged in the containing space and directly arranged on the first surface of the substrate;

The optical element is arranged on the first surface of the substrate;

Wherein, the distance between the laser diode chip and the optical element is configured such that the emitted light of the laser diode chip is emitted from the cover after changing the optical path by the optical element.

Another aspect of the present invention provides a distance detection device, including:

The aforementioned laser diode packaging module is used to emit laser pulses in a direction at a certain angle with the first surface of the substrate of the laser diode packaging module;

The collimating lens is arranged on the outside of the cover and is used to collimate the light emitted from the cover;

The first optical path changing element is arranged on the outside of the cover, and is used to change the optical path of the exit light emitted from the cover so that the laser pulse from the laser diode package module is substantially along the The direction of the center axis of the collimating lens is incident on the collimating lens.

In another aspect of the present invention, there is also provided an electronic device, including the aforementioned laser diode packaging module, and the electronic device includes an unmanned aerial vehicle, a car, or a robot.

In the laser diode package module of the present invention, the laser diode chip is directly arranged on the first surface of the substrate, and no additional structures such as spacers or heat sinks are provided, and the edge-emitting laser diode chip itself is used. Thickness, matching the optical element, and optimizing the design of the optical element and the distance from the laser diode chip, so that the emitted light of the laser diode chip can be emitted from the cover after changing the optical path through the optical element. The laser diode packaging module of the present invention can not only realize the effect of improving the light output efficiency of the PLD chip, but also can realize the array packaging use of a plurality of PLD chips. The packaging scheme of the present invention can be packaged through a substrate packaging operation method, the packaging efficiency is high, and the packaged chip is suitable for surface mounting technology (Surface Mounted Technology, SMT).

In addition, the distance detection device implemented based on the package module structure according to the embodiment of the present invention can increase the transmission power, quickly respond to the fast pulse drive signal, improve the reliability and accuracy, reduce the production cost and complexity, and improve Increased production efficiency.

Description of the drawings

Figure 1 shows a schematic diagram of the structure of the laser diode in the current laser diode package module;

2 shows a schematic diagram of the structure of a laser diode in a laser diode package module according to an embodiment of the present invention;

Figure 3 shows a cross-sectional view of the laser diode of Figure 2 along the B-B direction;

4A shows a schematic structural diagram of the fast axis divergence angle of the laser diode in the laser diode package module in an embodiment of the present invention;

4B shows a schematic structural diagram of the slow axis divergence angle of the laser diode in the laser diode package module in an embodiment of the present invention;

Figure 5A shows a cross-sectional view of a laser diode package module structure in an embodiment of the present invention;

FIG. 5B shows a top view of the laser diode package module structure in FIG. 5A after the cover is removed;

5C shows a top view of the laser diode package module structure in another embodiment of the present invention after the cover is removed;

5D shows a cross-sectional view of a laser diode package module structure in another embodiment of the present invention;

FIG. 5E shows a top view of the laser diode package module structure in FIG. 5D after the cover is removed;

6A shows a schematic structural diagram of the positional relationship between the laser diode chip and the slide stage in the laser diode package module structure in an embodiment of the present invention;

6B shows a schematic structural diagram of the positional relationship between the laser diode chip and the mounting table in the laser diode package module structure in another embodiment of the present invention;

6C shows a schematic structural diagram of the positional relationship between the laser diode chip and the slide stage in the laser diode package module structure in another embodiment of the present invention;

Fig. 7 shows a schematic diagram of an embodiment of the distance detection device of the present invention.

Figure 8 shows a schematic diagram of another embodiment of the distance detection device of the present invention;

Fig. 9 shows a schematic diagram of another embodiment of the distance detection device of the present invention.

Detailed ways

In order to make the objectives, technical solutions, and advantages of the present invention more obvious, the exemplary embodiments according to the present invention will be described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments of the present invention, and it should be understood that the present invention is not limited by the exemplary embodiments described herein. Based on the embodiments of the present invention described in the present invention, all other embodiments obtained by those skilled in the art without creative work should fall within the protection scope of the present invention.

In the following description, a lot of specific details are given in order to provide a more thorough understanding of the present invention. However, it is obvious to those skilled in the art that the present invention can be implemented without one or more of these details. In other examples, in order to avoid confusion with the present invention, some technical features known in the art are not described.

It should be understood that the present invention can be implemented in different forms and should not be construed as being limited to the embodiments presented here. On the contrary, the provision of these embodiments will make the disclosure thorough and complete, and will fully convey the scope of the present invention to those skilled in the art.

The purpose of the terms used here is only to describe specific embodiments and not as a limitation of the present invention. When used herein, the singular forms "a", "an" and "the/the" are also intended to include plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "composition" and/or "including", when used in this specification, determine the existence of the described features, integers, steps, operations, elements and/or components, but do not exclude one or more other The existence or addition of features, integers, steps, operations, elements, components, and/or groups. As used herein, the term "and/or" includes any and all combinations of related listed items.

In order to thoroughly understand the present invention, a detailed structure will be proposed in the following description to explain the technical solution proposed by the present invention. The optional embodiments of the present invention are described in detail as follows. However, in addition to these detailed descriptions, the present invention may also have other embodiments.

At present, the laser diode chip packaging has the problems of large package volume, large parasitic inductance, and narrow pulses cannot be generated, and the expected light output efficiency cannot be achieved, and the process is relatively complicated.

The current method to solve this problem, as shown in FIG. 1, is to provide a spacer 102, such as a ceramic spacer, on the substrate 100, and then form a laser diode chip 101 on the spacer 102 to achieve vertical light emission. , But by setting a heat sink or spacer under the PLD chip, the process requires that the PLD chip's light outlet and the spacer are precisely aligned to improve the divergence angle of the optical port. This type of process is more complicated and it is not easy to implement multiple PLD chips. Package level array.

In order to solve the above problems, the present invention provides a laser diode package module. The packaging module includes:

The substrate has a first surface and a second surface opposite to each other;

The optical element is arranged on the first surface of the substrate;

Example one

Hereinafter, a specific embodiment of the laser diode package module of the present invention will be described in detail with reference to the accompanying drawings. In the case of no conflict, the following embodiments and features in the implementation can be combined with each other.

Fig. 5A shows a cross-sectional view of the laser diode package module structure in an embodiment of the present invention; Fig. 5B shows a front view of the laser diode package module structure in Fig. 5A after the cover is removed. In one embodiment, the present invention The laser diode package module structure includes a substrate 300 having a first surface 30 and a second surface 32.

Wherein, the substrate 300 may include various types of substrates such as a PCB substrate (Printed Circuit Board), a ceramic substrate, a pre-mold substrate, etc. The ceramic substrate may be aluminum nitride or aluminum oxide. Substrate.

Among them, the PCB is made of different components and a variety of complex process technology processing, etc. The structure of the PCB circuit board has a single-layer, double-layer, and multi-layer structure, and different hierarchical structures have different manufacturing methods. .

Optionally, the printed circuit board is mainly composed of pads, vias, mounting holes, wires, components, connectors, filling, electrical boundaries, and the like.

Further, the common layer structures of printed circuit boards include single layer PCB, double layer PCB, and multi layer PCB. The specific structure is as follows:

(1) Single-layer board: a circuit board with copper on one side and no copper on the other side. Usually components are placed on the side without copper, and the side with copper is mainly used for wiring and soldering.

(2) Double-layer board: a circuit board with copper on both sides, usually called the top layer on one side and the bottom layer on the other side. Generally, the top layer is used as the surface for placing components, and the bottom layer is used as the welding surface for components.

(3) Multilayer board: A circuit board that contains multiple working layers. In addition to the top and bottom layers, it also contains several intermediate layers. Usually the intermediate layers can be used as wire layers, signal layers, power layers, ground layers, etc. The layers are insulated from each other, and the connection between the layers is usually achieved through via holes.

Among them, the printed circuit board includes many types of working layers, such as a signal layer, a protective layer, a silk screen layer, an internal layer, etc., which will not be repeated here.

In addition, the substrate mentioned in this application can also be a ceramic substrate. The ceramic substrate means that the copper foil is directly bonded to the _{surface of the aluminum oxide (Al 2} O ₃ ) or aluminum nitride (AlN) ceramic substrate (single-sided) at high temperature. Or double-sided) on the special craft board. The made ultra-thin composite substrate has excellent electrical insulation properties, high thermal conductivity, excellent solderability and high adhesion strength, and can be etched into various patterns like a PCB board, and has a large current carrying capacity. ability.

Further, the substrate may be a pre-mold (Pre-mold) substrate, wherein the pre-molded substrate has injection molded wires and pins, and the molded wires are embedded in the main structure of the substrate, and the pins Located on the surface of the main structure of the substrate, such as the inner surface and/or the outer surface, etc., to realize the electrical connection between the substrate and the laser diode chip, the driving chip, and the circuit board, respectively.

Wherein, the preparation method of the pre-mold substrate can be formed through a conventional injection molding process, planer excavation and mold embossing molding successively, which will not be repeated here.

Wherein, the injection material of the pre-mold substrate can be a conventional material, such as a thermally conductive plastic material, etc., and is not limited to a certain one. Among them, the pre-mold substrate The shape is limited by the injection frame and is not limited to one.

Further, the laser diode packaging module structure further includes a laser diode chip 303, which is arranged in the containing space. Optionally, the laser diode chip 303 is directly mounted on the first surface 30 of the substrate 300.

Specifically, in the present invention, the spacer or heat sink shown in FIG. 1 is no longer arranged between the laser diode chip 303 and the substrate 300, but the laser diode chip 303 is directly arranged on the substrate. At 300, the process can be further simplified through the above-mentioned configuration, and the array packaging of multiple laser diode chips can be realized.

It should be noted that the direct mounting in the present invention means that the laser diode chip 303 is no longer provided with a gasket or heat sink, but a conductive adhesive layer can still be provided between the laser diode chip 303 and the substrate 300 And/or the slide table, since the thickness of the conductive adhesive layer and the slide table is usually very thin, it is also called direct mounting in the present invention.

As an example, the laser diode chip 303 is a side laser, that is, the side of the laser diode chip emits light. The structure of the laser diode chip is shown in Figures 2 and 3, and Figure 2 shows the laser diode provided by the present invention. A schematic diagram of the structure of the laser diode in the packaged module; Figure 3 shows a cross-sectional view of the laser diode in Figure 2 along the BB direction; wherein, the laser diode chip includes: a first electrode 20 and a second electrode 21 arranged opposite to each other, the first The surface where the electrode 20 is located is mounted on the first surface of the substrate.

Optionally, the first electrode 20 and the second electrode 21 are both metallized electrodes, the first electrode 20 is disposed on the bottom surface of the laser diode chip, the first electrode 20 is an n-electrode, and the first electrode 20 is an n-electrode. Two electrodes 21 are arranged on the top surface of the laser diode chip, and the second electrode 21 is a p-electrode.

In an example, as shown in FIG. 5A, the first electrode of the laser diode chip 303 is mounted on the first surface of the substrate through a conductive adhesive layer, for example, mounted on the first surface of the substrate 300 30 on the corresponding substrate metal layer 3041.

Wherein, the laser diode chip 303 is a bare die, that is, a small piece of circuited "die" cut from a wafer (Wafer), which is mounted on the substrate by means of die bond. 300 up. Die bonding refers to a process in which a chip is bonded to a designated area of a substrate through a glue, generally a conductive glue or an insulating glue, to form a thermal path or an electrical path to provide conditions for subsequent wire bonding. In this embodiment, the first surface of the substrate is covered with a patterned substrate metal layer. For example, as shown in FIGS. 5A and 5B, the first surface 30 of the substrate 300 is provided with The substrate metal layer 3041 is electrically connected to the laser diode chip 303. The substrate metal layer 3041 can be a pattern formed by etching the copper foil on the ceramic substrate. The substrate metal layer can also be used for various devices on the substrate. Used as an alignment mark during film loading.

Exemplarily, as shown in FIG. 5C, a plurality of laser diode chips are mounted on the first surface of the substrate, and each laser diode chip corresponds to a substrate metal layer 3041, and the substrate metal layers 3041 are isolated from each other. The layer 3041 is also used to lead out the electrodes of the laser diode chip 303 on the bottom surface to facilitate electrical connection with other devices. Further, the first electrode of each laser diode chip 303 (that is, the electrode attached to the substrate, also called the electrode on the bottom surface of the laser diode chip) is attached to a conductive adhesive layer (not shown) corresponding to Mounted on the first surface of the substrate, for example, mounted on the corresponding substrate metal layer 3041 on the first surface 30 of the substrate 300, and adjacent conductive adhesive layers are isolated from each other to prevent laser diodes The electrodes on the bottom surface of the chip are electrically connected.

In an example, the area of the conductive adhesive layer is larger than the area of the bottom surface of the laser diode chip; and/or the conductive adhesive layer is electrically connected to the pads on the substrate through wires to connect the The first electrode is led out.

In this embodiment, the laser diode chip 303 is mounted on the substrate through a conductive adhesive layer (not shown) to form an electrical path. The material of the conductive adhesive layer (not shown) includes conductive silver. Paste, solder, or conductive die attach film (DAF), where the conductive silver paste may be ordinary silver paste or nano-silver paste. The solder includes but is not limited to AuSn20. Optionally, In order to ensure the placement accuracy and high heat dissipation, AuSn20 eutectic is used for mounting. Since solder such as AuSn20 is used as the conductive adhesive layer, it is basically non-volatile or low-volatile compared to other solders containing volatile flux (such as solder paste solder), so there is no generation of volatile substances in the solder. The pollution of the laser diode chip and the reflective surface affects the light output efficiency of the laser diode chip.

Exemplarily, the second electrode is electrically connected to the substrate through a wire 305, for example, the second electrode (for example, a p-electrode) is electrically connected to a pad 306 provided on the substrate through a wire 305, optionally Ground, the wire 305 may use a metal wire, such as a gold wire, where the diameter of the gold wire is about 1 mil (25.4 microns) or other suitable diameters. The number of the wires 305 can be set reasonably according to actual needs. A plurality of the wires can be used side by side to realize the electrical connection between the second electrode and the pad, and the wire arc is pulled as low as possible.

In an example, the shape of the laser diode chip is a cylindrical structure, for example, it can be a rectangular parallelepiped structure, or it can be a polyhedron, a cylindrical shape and other suitable shapes, which will not be listed here. The laser diode chip The exit surface of the laser diode chip can be set on the side surface of one end of the cylindrical structure of the laser diode chip, and the side surface can be the smallest surface of the laser diode chip. Further, the bottom surface of the laser diode chip is mounted in the accommodating space. The area of the bottom surface of the laser diode chip is relatively large, for example, larger than the area of the exit surface. Optionally, the bottom surface of the laser diode chip is mounted on the first surface of the substrate, and the side surface of the laser diode chip emits light. Because of the arrangement of the optical elements, the bottom surface of the laser diode chip can be mounted in the containing space while making the emitted light beam The laser diode chip can emit light in a direction substantially perpendicular to the first surface, and the area of the bottom surface of the laser diode chip is relatively large, which facilitates the placement of the chip and the location of the package module in the complete device.

In a specific embodiment, the laser diode chip has a rectangular parallelepiped structure, and the light exit port 22 (or light exit surface) of the laser diode chip is disposed on the side surface of one end of the rectangular parallelepiped structure, as shown in FIGS. 4A and 4B. The exit surface of the laser diode chip is set on the side of the right end of the rectangular parallelepiped structure. In this application, in order to no longer provide a gasket under the laser diode chip and simplify the process, it is necessary to further improve the position of the light exit port to fully Utilize the thickness of the laser diode chip.

Specifically, the light outlet 22 is arranged at the top position of the laser diode chip. Optionally, the light exit 22 is arranged below the second electrode 21, and is close to the second electrode 21, and there is no gap between the second electrode, so as to maximize the position of the light exit, and then The light emitted by the laser diode chip can be emitted after changing the optical path through the optical element, which improves the light output efficiency of the PLD chip.

Further, the light outlet includes a fast axis diverging in a first direction and a slow axis diverging in a second direction. The laser diode chip emits an elliptical light spot along a direction perpendicular to the first surface of the substrate (herein referred to as Is the y direction) the beam divergence angle is large, called the fast axis, and the beam divergence angle along the x direction (where the x direction is perpendicular to the y direction) is small, called the slow axis; between the laser diode chip and the optical element The distance of is configured such that the emitted light in the fast axis direction and the slow axis direction is emitted from the cover after changing the optical path through the optical element, wherein the first direction is perpendicular to the second direction.

4A and 4B, the first direction is a direction extending along the thickness of the laser diode chip, where the thickness refers to the distance between the top and bottom of the laser diode chip, such as the first electrode The distance between the lower surface of 20 and the upper surface of the second electrode 21.

Specifically, in an embodiment of the present invention, the thickness of the laser diode chip is 100 μm-200 μm, that is, the height distance between the plane of the light outlet and the bottom side of the laser diode chip is designed to be 100 to 200 μm, that is, the light outlet It is arranged on the top surface to make full use of the thickness of the laser diode chip.

Wherein, the second direction is a direction extending along the width of the laser diode chip, as shown in FIG. 4B. For example, in the laser diode chip in a top horizontal plane perpendicular to the paper, the front-to-rear direction is the The direction in which the horizontal width of the laser diode chip extends.

In the absence of special instructions, the thickness direction and the width direction refer to this explanation.

Wherein, the divergence angle of the emitted light of the laser diode chip in the slow axis direction is 5°-15°, and/or the divergence angle in the fast axis direction is 25°-35°. In a specific embodiment of the present invention, as shown in FIGS. 4A and 4B, the divergence angle of the emitted light of the laser diode chip in the slow axis direction is 10°, and/or, in the fast axis direction The divergence angle is 30°.

Due to the existence of the divergence angle, the divergence angle of the light-emitting port needs to be taken into account during packaging to ensure that the light beam can still be emitted through the optical element after divergence. In order to achieve the purpose, the laser diode chip and the The distance between the optical elements is further limited, and not any distance can achieve the above-mentioned purpose, especially when there is no spacer under the laser diode chip, it is directly mounted on the substrate.

The distance between the laser diode chip and the optical element is configured such that the emitted light of the laser diode chip is emitted from the cover after changing the optical path by the optical element. In the present invention, the distance between the laser diode chip and the optical element is 50 μm-100 μm to ensure that even at the maximum angle of the fast axis in the fast axis direction, all light emitted from the edge of the PLD can pass through the optical element Reflected, and at the same time in the direction of the slow axis, it is ensured that even at the maximum angle of the slow axis, all the light emitted from the edge of the PLD can be emitted through the optical element. For example, the distance between the laser diode chip and the optical element is 50 μm, 55 μm, 60 μm, 65 μm, 70 μm, 75 μm, 80 μm, 85 μm, 90 μm, 95 μm, 100 μm, etc.

In an embodiment of the present invention, the distance between the laser diode chip and the optical element is 50-70 μm, for example, the distance between the laser diode chip and the optical element is 50 μm, 55 μm, 60 μm, 65μm or 70μm, etc., can be selected according to actual needs.

Wherein, the optical element includes a reflecting mirror, the reflecting mirror includes at least one reflecting surface, and the reflecting surface is arranged in the containing space for making the emitted light of the laser diode chip reflected by the reflecting surface. It is emitted through the light-transmitting area. Optionally, the emitted light of the laser diode chip is reflected by the reflective surface and then emitted through the light-transmitting area in a direction substantially perpendicular to the first surface of the substrate Get out.

Wherein, the material of the reflector can be any material that can reflect light, for example, it can be glass or semiconductor.

In an example, the package module further includes a semiconductor with an anisotropic structure, where the semiconductor with an anisotropic structure may include but is not limited to silicon, and may also be other materials such as germanium and III-V groups ( Such as GaAs) compound semiconductors and other semiconductor materials. Optionally, the semiconductor includes a semiconductor wafer, such as a single crystal silicon wafer.

In an example, the reflecting surface is specifically an inclined surface prepared by etching the semiconductor using anisotropy. Since the semiconductor itself has a reflection effect on the light beam, the inclined surface of the semiconductor can be directly used as the reflecting surface. As an example, the semiconductor is a silicon wafer, and silicon, the material of the semiconductor, has anisotropic characteristics due to its diamond cubic lattice structure, and has anisotropic characteristics in terms of etching. The [100] crystal orientation of the silicon wafer forms an angle of 54.74° with the [111] crystal orientation. When the [100] is etched downwards, because the [111] crystal orientation is very different from the [100] crystal orientation in the etching speed, the [111] crystal orientation is basically not etched, and the [100] crystal orientation is quickly corroded, thus A trapezoid of 54.74° is formed, that is, the angle between the inclined surface of the semiconductor prepared by etching using anisotropy and the bottom surface of the semiconductor is approximately 54.74°. Because the angle is determined by the material lattice structure, it will not change with the fluctuation of the parameters of the production process, so the angle of the inclined plane prepared from the silicon wafer is basically 54.74°. Wherein, the etching can use any suitable etchant, for example, an inorganic alkali solution or an organic alkali solution is used as the etchant. The inorganic alkali solution includes but is not limited to KOH, and the organic alkali solution includes but is not limited to tetramethyl Base ammonium hydroxide (TMAH).

Further, the semiconductor is etched using anisotropy to prepare at least one inclined surface. In one example, at least two obliquely arranged reflective surfaces are arranged on different inclined surfaces prepared by etching the semiconductor using anisotropy. Taking a silicon wafer as an example, the silicon wafer is etched using anisotropy to obtain an inclined surface, and at least one inclined surface may be prepared by a suitable etching method, or it may be a surface with two opposite inclined surfaces. Silicon wafer 301. Wherein, the cross-sectional shape of the semiconductor (for example, the silicon wafer 301) may be a right-angled trapezoid or an isosceles trapezoid.

Wherein, the reflective surface mentioned in this article is set on different inclined surfaces prepared by etching the semiconductor using anisotropy, which may refer to directly using the inclined surface of the semiconductor (such as a silicon wafer) as the reflective surface , Or the reflective surface includes a reflective film plated on an inclined surface prepared by etching the semiconductor using anisotropy. For light beams with a wavelength of 300 to 1200 nm, the quantum efficiency absorbed by single crystal silicon exceeds 50%. In one embodiment, the wavelength of the light beam emitted by the laser diode chip is about 905 nm. Within this range, the reflectivity of single crystal silicon is roughly around 70%. Optionally, in the case where single crystal silicon is used for the semiconductor, in order to increase the reflectivity, a reflective film is plated on the inclined surface of the single crystal silicon. For example, as shown in FIG. 5B, the silicon wafer 301 uses anisotropy. The inclined surface prepared by etching is coated with a reflective film 302 to increase the reflectivity of the light on the reflective surface, thereby increasing the output power of the laser. Wherein, the material of the reflective film 302 may include any suitable metal material that reflects light. For example, the reflective film 302 includes at least one of gold, silver and aluminum, wherein gold or silver has a wavelength of 905 nm. The reflectivity of the beam is above 95%. The reflective film 302 can be formed on the inclined surface of the semiconductor using a deposition method such as vacuum evaporation.

In the die bond process, due to the downward pressure, the sharp corners of the bottom of the semiconductor are relatively thin, and there may be a risk of corner chipping, which will cause the inclined surface to break near the bottom and generate debris. In order to avoid the above-mentioned corner chipping problem, cuts or grooves are provided at the sharp corners of the bottom surface of the semiconductor. Since the size and forming position of the pre-set cut or groove are more controllable than the chipping formed by the downward pressure, it can be ensured that the reflective surface can receive the emission from the laser diode chip without causing the chipping. All the light spots of the emitted light.

In one example, a cut is provided at the sharp corner of the bottom surface of the semiconductor (for example, silicon wafer 301). Optionally, the cut is specifically a cut formed by removing part of the bottom sharp corner of the semiconductor, which can be etched The method to remove part of the bottom sharp corners. The etching can use a traditional dry etching process, such as reactive ion etching, ion beam etching, plasma etching, laser ablation, or any combination of these methods. A single etching method may be used, or more than one etching method may be used. In another example, a groove is provided at the sharp corner of the bottom surface of the semiconductor (for example, silicon wafer 301). Optionally, the groove is provided at the edge of the sharp corner of the bottom surface and separates from the semiconductor. The bottom faces the depth of the recessed portion of the top surface of the semiconductor. Wherein, the groove may be formed by an etching method, and the etching includes but is not limited to wet etching or dry etching. In one example, the method for forming the groove may be: on the bottom surface of the semiconductor For example, a photoresist mask is formed, and then a predetermined groove pattern is defined in the photoresist through a photolithography process, and then the photoresist layer is used as a mask, and the semiconductor is etched from the bottom surface to The groove is formed, and the photoresist layer is finally removed.

In a specific embodiment of the present invention, the depth of the groove is within 20 μm.

In one example, an oblique reflective surface is provided in the package module, for example, as shown in FIG. 5A and FIG. 5B, the reflective surface is included in the semiconductor (such as silicon wafer 301) using anisotropy. The reflective film 302 is plated on the inclined surface prepared by etching, and the reflective surface is arranged opposite to the exit surface of the laser diode chip 303, so that the exit light of the laser diode chip 303 is reflected by the reflective surface Then it is emitted through the light-transmitting area.

In another example, as shown in FIGS. 5A and 5B, an oblique reflective surface is provided in the package module, and the reflective surface is included in the semiconductor (such as a silicon wafer 301) using anisotropy. The reflective film 302 is plated on the inclined surface prepared by etching, and the reflective surface is arranged opposite to the exit surface of at least two laser diode chips 303 arranged side by side, so that each laser diode chip 303 has a The outgoing light is reflected by the reflective surface and then emitted through the light-transmitting area, thereby realizing a 1×N one-dimensional multi-line packaging structure, where N is greater than or equal to 2.

In this embodiment, the semiconductor (for example, silicon wafer 301) is mounted on the first surface 30 of the substrate 300 through an adhesive layer (not shown), for example, on the first surface of the substrate 300 30 is provided with a substrate metal layer 3042 corresponding to the semiconductor, and the semiconductor is attached to the surface of the substrate metal layer 3042 on the first surface 30 of the substrate through an adhesive layer.

Wherein, the material of the adhesive layer can be the same material as the aforementioned conductive adhesive layer, and the material of the conductive adhesive layer (not shown) includes conductive silver paste, solder, or conductive die attach film (die attach film). film, DAF), wherein the conductive silver paste can be ordinary silver paste or nano-silver paste. The solder includes but is not limited to AuSn20. Optionally, in order to ensure the placement accuracy and high heat dissipation, use AuSn20 eutectic for chip mounting. In one example, the method of using AuSn eutectic for chip mounting includes the following steps: bonding the back surface of the semiconductor and the surface of the substrate metal layer together, where the substrate metal layer may be an AuSn alloy, The back surface of the semiconductor is provided with gold, and then heating is performed to form an alloy between the gold on the back surface of the semiconductor and the metal layer of the substrate, which plays the role of fixing the semiconductor on the first surface of the substrate and making a good electrical connection.

In another example, the adhesive layer includes adhesive glue. The adhesive glue is applied to the position on the substrate where the semiconductor is scheduled to be placed, and then the semiconductor is placed on the adhesive glue, and then baked and cured, so that the semiconductor Mounted on the first surface of the substrate.

In another embodiment of the present invention, the reflecting mirror includes a glass prism, wherein the angle between the reflecting surface of the glass prism and the horizontal bottom surface where the reflecting mirror is located is 30-60°, for example , The included angle between the reflecting surface and the horizontal bottom surface where the reflecting mirror is located is 45°, so that the emitted light of the laser diode chip changes the light path through the optical element and then interacts with the laser diode package module. The first surface of the substrate emits laser pulses in a substantially vertical direction.

Furthermore, in order to emit all the outgoing light, the length of the optical element (reflecting surface) is increased in the slow axis direction to ensure that even at the maximum angle of the slow axis, all light emitted from the edge of the PLD can pass through the mirror Reflect out. Wherein, the length direction is the width direction of the laser diode chip, that is, the front and back direction of the first surface. In an example of the present invention, the width of the end face of the light exit port of the PLD chip is designed to be 100-400 μm, and the length of the reflector is designed to be 800-1000 μm.

In a specific embodiment, the width of the end face of the light exit port of the PLD chip is designed to be 100 μm, 200 μm, or 400 μm, and the length of the reflector is designed to be 800 μm, 900 μm, or 1000 μm.

Furthermore, unlike the conventional centered design of the laser diode chip, the laser diode chip in the present invention is placed on one side, closer to the optical element, to ensure that the output efficiency is improved without the spacer.

As shown in FIGS. 6A-6C, the package module further includes: a slide table 310, the cutting table 310 is set between the substrate and the laser diode chip, that is, the slide table 310 is set on the On the first surface of the substrate, the laser diode chip is arranged on the slide stage 310.

While keeping the distance between the PLD chip and the optical element constant (to ensure reflection efficiency), the closer the stage is to the optical element, the solder is likely to contaminate the mirror surface or bridging short circuit; the farther away the stage is from the optical component, the less likely the mirror surface is to be soldered Pollution, under the premise of ensuring that the reflective surface and the solder do not pollute and bridge, the mirror surface can also be closer to the PLD, thereby improving the reflection efficiency. The laser diode chip cannot be infinitely close to the optical components. The closer the laser diode chip is to the mounting table, the greater the dangling of the solder between the laser diode chip and the carrier. The light-emitting end of the laser diode chip will easily lead to poor heat dissipation and cause reliability connection problems between the chip, the carrier and the solder.

Wherein, the positional relationship between the slide stage 310 and the laser diode chip includes three types. As shown in FIG. 6A, on the side close to the optical element, the edge of the laser diode chip and the slide The edges of the stage 310 are aligned, or, as shown in FIG. 6B, the laser diode chip and the stage 310 are staggered, and the edge of the laser diode chip exceeds the edge of the stage 310 within 30 μm, that is, The laser diode chip is closer to the optical element than the stage 310, and the distance between the edge of the laser diode chip and the edge of the stage 310 is within 30 μm, or, as shown in FIG. 6C As shown, the laser diode chip and the slide table 310 are arranged staggered, and the edge of the slide table exceeds the edge of the laser diode chip within 50 μm, that is, the laser diode chip is compared with the slide The stage 310 is farther away from the optical element, and the distance between the edge of the laser diode chip and the edge of the slide stage 310 is within 50 μm.

For example, in the embodiment of the present invention, in the direction close to the side of the optical element, the edge of the laser diode chip exceeds the edge of the stage by 2 μm, 5 μm, 8 μm, 12 μm, 15 μm, 18 μm, 20 μm , 22μm, 25μm, 28μm or 30μm; or the edge of the stage is beyond the edge of the laser diode chip by 2μm, 5μm, 8μm, 12μm, 15μm, 18μm, 20μm, 22μm, 25μm, 28μm, 30μm; 32μm, 35μm , 38μm, 40μm; 42μm, 45μm, 48μm or 50μm.

Further, as shown in FIG. 5C, a plurality of the laser diode chips 303 are mounted on the first surface of the substrate 300, wherein the first electrode (for example, n-electrode) of each laser diode chip 303 ) Corresponds to a substrate metal layer 3041 and is mounted on the first surface of the substrate 300, and adjacent substrate metal layers 3041 are isolated from each other.

In one example, as shown in FIG. 5C, the second electrodes (for example, p-poles) of the plurality of laser diode chips 303 opposite to the same reflective surface are electrically connected to the substrate 300 through a wire 305 The same bonding pad 306, wherein the bonding pad 306 has a long strip shape and is arranged outside the surface of the laser diode chip 303 opposite to the exit surface. The material of the pad 306 may include aluminum or other suitable metal materials.

Optionally, a plurality of the laser diode chips are juxtaposed in the third direction of the first surface to form a laser diode chip array, and the emitted light of the laser diode chip array changes the light path from the laser diode chip array through the optical element. The cover is emitted. Wherein, the third direction is the length direction of the substrate, which is consistent with the length direction of the laser diode chip, that is, a direction from left to right.

Wherein, the fourth direction refers to the width direction of the substrate, which is consistent with the width direction of the laser diode chip. A plurality of the laser diode chip arrays and a plurality of the optical elements arranged opposite to the laser diode chip array are arranged in a fourth direction of the first surface, wherein the third direction and the fourth direction The direction is vertical.

By arranging a plurality of the laser diode chips and the optical elements in the third and fourth directions, an M×N two-dimensional multi-line package is realized. For example, as shown in FIG. 5D and FIG. 5E, each optical element is arranged opposite to the exit surface of six laser diode chips 303 arranged side by side, so that the emitted light of each laser diode chip 303 passes through the optical element. After reflection, it is emitted through the light-transmitting area, wherein the number of laser diode chips 303 opposite to the same reflective surface can be reasonably selected according to the requirements of the actual device. It is worth mentioning that only a semiconductor with one inclined surface is shown in FIG. 5D, and the semiconductor may also be a semiconductor with at least two inclined surfaces.

The multiple laser diode chips opposite to the same optical element can be arranged at any suitable interval on the first surface of the substrate. Optionally, as shown in FIG. 5D, the multiple laser diode chips opposite to the same reflective surface The chips 303 are arranged at equal intervals on the first surface of the substrate 300, so that the emitted lights of different laser diode chips 303 reflected by the reflecting surface are emitted at equal intervals. When the package module of the present application is applied to a laser radar , Each light emitted from the light-transmitting area must correspond to each receiver one-to-one, that is, part of the laser light emitted by each laser diode chip is reflected by the object back to the corresponding receiver, so the emission and reception The positions of the laser diodes must be calibrated to make them correspond one-to-one. Therefore, the laser diode chips 303 are arranged at equal intervals to facilitate the arrangement of the receiver.

In the above embodiment, the distances between all the laser diode chips and the optical elements are equal, and all need to satisfy that the distance between the laser diode chip and the optical elements is 50 μm-100 μm to ensure that the distance between the laser diode chip and the optical element is 50 μm-100 μm. The light of each laser diode chip on the reflective surface is generally uniform.

Because of the difference between the beam waist and divergence angle of the fast and slow axes, the beam quality BPP of the fast and slow axes of the semiconductor laser differs greatly. Therefore, the package module of the present invention may also optionally include a collimating element for beam collimation. Straight, reduce the divergence angle of the beam in the fast axis direction or reduce the divergence angle of the fast axis and the slow axis direction, the collimating element is arranged between the laser diode chip and the reflective surface, so that the laser The emitted light from the diode chip reaches the reflecting surface after passing through the collimating element. The collimating element eliminates the astigmatism between the fast and slow axes, improves the beam quality, compresses the divergence angle of the beam in the fast axis direction, and improves the laser diode chip's Radiation utilization rate. Wherein, the collimating element may be any element known to those skilled in the art that can collimate light, such as a cylindrical lens, a D lens, an optical fiber rod, an aspheric lens, and the like.

Taking the collimating element as a cylindrical lens as an example, the cylindrical lens is arranged between the laser diode chip and the reflecting surface in order to make all the emitted light reflected from the exit surface of each laser diode chip 303 reach the cylindrical lens The curved surface of the cylindrical lens is opposite to the exit surface of the laser diode chip 303, so that the emitted light of the laser diode chip 303 irradiates the curved surface of the cylindrical lens 303. Optionally, the size of the curved surface of the cylindrical lens 309 is larger than the size of the spot of the emitted light emitted from the laser diode chip 303 on the plane where the incident surface of the cylindrical lens is located, so as to ensure that all the emitted light can illuminate To the cylindrical lens and be collimated.

Further, the laser diode package module structure further includes a cover body, which is disposed on the first surface 30 of the substrate 300, and an accommodating space is formed between the substrate 300 and the cover body, wherein the cover body is connected to the cover body. The opposite surface of the substrate 300 is at least partially provided with a light-transmitting area.

In an embodiment of the present invention, the cover body is not limited to a certain structure. The cover body is at least partially provided with a light-transmitting area, and the emitted light of the laser diode chip passes through after being reflected by the reflecting surface. The light-transmitting area is emitted. For example, in this embodiment, the cover is a metal shell with a glass window.

Further, as shown in FIGS. 5A and 5D, the cover includes a U-shaped or square cover body 307 with a window, and a light-transmitting plate 308 that covers the window to form the light-transmitting area. The emitted light of the laser diode chip 303 is reflected and emitted from the light-transmitting plate, wherein the light-transmitting plate is parallel to the first surface of the base; or the cover is a plate-like structure that is completely light-transmissive. Further, the cover body provides a protection and airtight environment for the chip enclosed therein.

Exemplarily, the projection of the U-shaped cover body 307 with the window on the first surface of the substrate is circular or other suitable shapes, and the square cover body 307 is on the first surface of the substrate. The projection of is square, and the size of the square cover body matches the size of the substrate, which can effectively reduce the package size.

The material of the cover body can be any suitable material. For example, the material of the cover body includes metal, resin or ceramic. In an example, the material of the cover body 307 can optionally be a metal material, and the metal material can optionally be a material similar to the thermal expansion coefficient of the light-transmitting plate 308, for example, Kovar. Alloy, since the thermal expansion coefficients of the cover body 307 and the light-transmitting plate 308 are similar, when the light-transmitting plate is pasted on the window of the cover body 307, the generation of the light-transmitting plate due to the difference in the thermal expansion coefficient can be avoided. The problem of rupture. Optionally, the cover body may be fixedly connected to the first surface of the substrate by welding, and the welding may use any suitable welding method, such as parallel seam welding or energy storage welding. Exemplarily, the light-transmitting plate 308 is also adhered to the inner side of the window of the cover body.

Wherein, the light-transmitting plate 308 can be a commonly used light-transmitting material, such as glass, which must have high passability to the wavelength of the laser light emitted by the laser diode chip.

In another example, the cover is a plate-shaped structure that is completely light-transmissive. The plate-shaped structure is made of commonly used light-transmitting materials, such as glass, which must have high passability to the wavelength of the laser light emitted by the laser diode chip. Wherein, the overall structure of the substrate may be in the shape of a groove, the groove may be a square groove or a circular groove, and the cover is arranged on the top of the groove of the substrate and is joined with the top surface of the substrate to The groove is enclosed to form an accommodation space between the substrate and the cover body.

In the aforementioned package module solution, due to the short pin path, the parasitic inductance is greatly reduced compared with TO package, and the package can be packaged through the substrate package operation method, the packaging efficiency is high, and the packaged chip is suitable for SMT .

In order to improve the integration of the package, shorten the lead between the laser diode chip and the driving chip, and further reduce the inductance, the package module further includes a driving chip for controlling the emission of the laser diode chip 303, and the driving chip is arranged in the In the accommodating space, the driving chip is mounted on the first surface 30 of the substrate 300.

Optionally, in the package module, the laser diode chip can be placed as close to the drive chip as possible. The smaller the distance between the laser diode chip and the drive chip, the more effective the distributed inductance can be reduced. The loss of the transmitting module on the distributed inductance will be much smaller, and it is easier to achieve high-power laser emission. The reduction of the distributed inductance also makes it possible to drive narrow pulse lasers.

In a specific embodiment of the present invention, the package module further includes a switch chip, wherein the switch chip is also arranged in the accommodation space, wherein the switch chip includes a switch circuit, and the switch circuit is used in the Driven by the driving circuit, the laser diode chip is controlled to emit laser light.

In addition, other devices are also provided on the substrate, for example, FET devices or other types of switching devices, or switching device drive chips, necessary resistors and capacitors, and surface mount circuits (SMT IC) and other devices. The conductive material, such as conductive adhesive (including but not limited to solder paste), is mounted on the substrate through Surface Mounted Technology (SMT).

Wherein, the laser diode chip 303, the driving chip, the reflective surface and other devices are all mounted on the first surface of the substrate 300, and they are all arranged in the containing space between the cover and the substrate, optionally In the package module structure, a non-volatile or low-volatility conductive adhesive layer is used to mount on the first surface of the substrate. This arrangement can avoid the volatilization of volatile substances in the volatile conductive adhesive layer The pollution of the laser diode chip, the reflective surface and the light-transmitting area affects the light output efficiency of the laser diode chip.

In the laser diode package module of the present invention, the laser diode chip is directly arranged on the first surface of the substrate, no additional structures such as spacers or heat sinks are provided, and the thickness of the edge-emitting laser diode chip itself is used. , With the optical element, by optimizing the design of the optical element and the distance between the laser diode chip and the laser diode chip, the emitted light from the laser diode chip can be emitted from the cover after changing the optical path through the optical element. The laser diode packaging module of the present invention can not only realize the effect of improving the light output efficiency of the PLD chip, but also realize the array packaging use of a plurality of PLD chips. The packaging scheme of the present invention can be packaged through a substrate packaging operation method, the packaging efficiency is high, and the packaged chip is suitable for surface mounting technology (Surface Mounted Technology, SMT).

Example two

As shown in FIG. 7, the distance detection device 800 provided by the present invention includes a light emitting module 810 and a reflected light receiving module 820. The light emitting module 810 includes at least one laser diode package module in the first embodiment for emitting light signals, and the light signals emitted by the light emitting module 810 cover the FOV of the distance detection device 800; the reflected light receiving module 820 is used to receive the light emitted by the light emitting module 810 and reflect the light after encountering the object to be measured, and calculate the distance between the distance detecting device 800 and the object to be measured. The light emitting module 810 and its working principle will be described below with reference to FIG. 10.

As shown in FIG. 7, the light emitting module 810 may include a light emitter 811 and an optical beam expanding unit 812. The light emitter 811 is used to emit light, and the light beam expanding unit 812 is used to perform at least one of the following processes on the light emitted by the light emitter 811: collimation, beam expansion, uniform light, and field of view expansion. The light emitted by the light emitter 811 passes through at least one of the collimation, beam expansion, homogenization and FOV expansion of the light beam expansion unit 812, so that the emitted light becomes divergent and evenly distributed, which can cover a certain two-dimensional scene in the scene. Angle, as shown in Fig. 8, the emitted light can cover at least part of the surface of the object to be measured.

In one example, the light emitter 811 may be a laser diode. Regarding the wavelength of the light emitted by the light emitter 811, in one example, light with a wavelength between 895 nanometers and 915 nanometers may be selected, for example, light with a wavelength of 905 nanometers may be selected. In another example, light with a wavelength between 1540 nanometers and 1560 nanometers can be selected, for example, light with a wavelength of 1550 nanometers can be selected. In other examples, other suitable wavelengths of light can also be selected according to application scenarios and various needs.

In an example, the optical beam expansion unit 812 may be implemented by a one-stage or multi-stage beam expansion system. Wherein, the light beam expansion processing can be reflective or transmissive, or a combination of the two. In one example, a holographic filter may be used to obtain a large-angle beam composed of multiple sub-beams.

In another example, a laser diode array can also be used, and multiple beams of light can be formed by using laser diodes, and a laser similar to an expanded beam can also be obtained (for example, a VCSEL array laser).

In another example, a two-dimensional angle-adjustable micro-electromechanical system (MEMS) lens can also be used to reflect the emitted light. By driving the MEMS micro-mirror, the angle between the mirror and the beam is constantly changed to make the angle of the reflected light It changes all the time and diverges into a two-dimensional angle to cover the entire surface of the object to be measured.

The distance detection device is used to sense external environment information, for example, distance information, angle information, reflection intensity information, speed information, etc. of environmental targets. Specifically, the distance detection device of the embodiment of the present invention can be applied to a mobile platform, and the distance detection device can be installed on the platform body of the mobile platform. A mobile platform with a distance detection device can measure the external environment, for example, measuring the distance between the mobile platform and obstacles for obstacle avoidance and other purposes, and for two-dimensional or three-dimensional surveying and mapping of the external environment. In some embodiments, the mobile platform includes at least one of an unmanned aerial vehicle, a car, and a remote control car. When the distance detection device is applied to an unmanned aerial vehicle, the platform body is the fuselage of the unmanned aerial vehicle. When the distance detection device is applied to a car, the platform body is the body of the car. When the distance detection device is applied to a remote control car, the platform body is the body of the remote control car.

Since the light emitted by the light emitting module 810 can cover at least part of the surface or even the entire surface of the object to be measured, correspondingly, the light is reflected after reaching the surface of the object, and the reflected light receiving module 820 that the reflected light reaches is not a single point, but is Arrayed distribution.

The reflected light receiving module 820 includes a photoelectric sensing cell array 821 and a lens 822. Among them, after the light reflected from the surface of the object to be measured reaches the lens 822, based on the principle of lens imaging, it can reach the corresponding photoelectric sensing unit in the photoelectric sensing unit array 821, and then be received by the photoelectric sensing unit, causing photoelectricity. Sensed photoelectric response.

Since the light is emitted to the photoelectric sensing unit receiving the reflected light, the optical transmitter 811 and the photoelectric sensing unit array 821 are controlled by a clock control module (for example, the clock shown in FIG. 10 included in the distance detection device 800). The control module 830, or a clock control module other than the distance detection device 800, performs synchronous clock control on them. Therefore, according to the time of flight (TOF) principle, the distance between the point reached by the reflected light and the distance detection device 800 can be obtained.

In addition, since the photoelectric sensing unit is not a single point, but the photoelectric sensing unit array 821, it passes through a data processing module (for example, the data processing module 840 shown in FIG. 8 included in the distance detection device 800, or the distance detection The data processing of the data processing module outside the device 800 can obtain the distance information of all points in the field of view of the entire distance detection device, that is, the point cloud data of the distance from the external environment to which the detection device faces.

Based on the foregoing structure and working principle of the laser diode package module according to the embodiment of the present invention and the structure and working principle of the distance detection device according to the embodiment of the present invention, those skilled in the art can understand the electronic device according to the embodiment of the present invention The structure and working principle of, for the sake of brevity, I will not repeat them here.

Example three

With the development of science and technology, detection and measurement techniques are applied in various fields. Lidar is a perception system of the outside world, which can learn the three-dimensional information of the outside world, and is no longer limited to the plane perception of the outside world such as cameras. The principle is to actively transmit laser pulse signals to the outside, detect the reflected pulse signals, judge the distance of the measured object according to the time difference between emission and reception, and combine the emission angle information of the light pulse to reconstruct and obtain the three-dimensional depth information. .

The present invention provides a distance detection device, which can be used to measure the distance from the detection object to the detection device and the orientation of the detection object relative to the detection device. In one embodiment, the detection device may include radar, such as lidar. The detection device can detect the distance between the detection device and the detection device by measuring the time of light propagation between the detection device and the detection object, that is, the time-of-flight (TOF).

A coaxial optical path can be used in the distance detection device, that is, the beam emitted by the detection device and the reflected beam share at least part of the optical path in the detection device. Alternatively, the detection device may also adopt an off-axis optical path, that is, the light beam emitted by the detection device and the reflected light beam are respectively transmitted along different optical paths in the detection device. Fig. 8 shows a schematic diagram of the distance detection device of the present invention.

The ranging device 200 includes a ranging module 210, which includes a light source, that is, a transmitter 203 (which may include the above-mentioned transmitting circuit), a collimating element 204, and a detector 205 (which may include the above-mentioned receiving circuit, sampling circuit, and Arithmetic circuit) and optical path changing element 206. The ranging module 210 is used to emit a light beam, receive the return light, and convert the return light into an electrical signal. Among them, the transmitter 203 can be used to emit a light pulse sequence. In one embodiment, the transmitter 203 may emit a sequence of laser pulses. Optionally, the laser beam emitted by the transmitter 203 is a narrow-bandwidth beam with a wavelength outside the visible light range. The collimating element 204 is arranged on the exit light path of the emitter, and is used to collimate the light beam emitted from the emitter 203, and collimate the light beam emitted from the emitter 203 into parallel light and output to the scanning module. The collimating element is also used to condense at least a part of the return light reflected by the probe. The collimating element 204 may be a collimating lens or other elements capable of collimating a light beam.

In the embodiment shown in FIG. 8, the transmitting light path and the receiving light path in the distance measuring device are combined before the collimating element 204 through the light path changing element 206, so that the transmitting light path and the receiving light path can share the same collimating element, so that the light path More compact. In some other implementation manners, the transmitter 203 and the detector 205 may use their respective collimating elements, and the optical path changing element 206 is arranged on the optical path behind the collimating element.

In the embodiment shown in FIG. 8, since the beam aperture of the light beam emitted by the transmitter 203 is relatively small, and the beam aperture of the return light received by the distance measuring device is relatively large, the light path changing element can use a small area mirror to The transmitting light path and the receiving light path are combined. In some other implementations, the light path changing element may also use a reflector with a through hole, where the through hole is used to transmit the emitted light of the emitter 203 and the reflector is used to reflect the return light to the detector 205. In this way, the shielding of the back light from the support of the small reflector in the case of using the small reflector can be reduced.

In the embodiment shown in FIG. 8, the optical path changing element deviates from the optical axis of the collimating element 204. In some other implementations, the optical path changing element may also be located on the optical axis of the collimating element 204.

The distance measuring device 200 also includes a scanning module 202, which is used to sequentially change the light beams emitted by the light source to different propagation directions and exit to form a scanning field of view. The scanning module 202 is placed on the exit light path of the distance measuring module 210. The scanning module 202 is used to change the transmission direction of the collimated beam 219 emitted by the collimating element 204 and project it to the external environment, and project the return light to the collimating element 204 . The returned light is collected on the detector 205 via the collimating element 204.

Wherein, the scanning module 202 can refer to the corresponding description of the scanning module in the foregoing embodiment, which will not be repeated here.

The detector 205 and the transmitter 203 are placed on the same side of the collimating element 204, and the detector 205 is used to convert at least part of the return light passing through the collimating element 204 into electrical signals.

In one embodiment, an anti-reflection film is plated on each optical element. Optionally, the thickness of the antireflection film is equal to or close to the wavelength of the light beam emitted by the emitter 203, which can increase the intensity of the transmitted light beam.

In one embodiment, a filter layer is plated on the surface of an element located on the beam propagation path in the distance measuring device, or a filter is provided on the beam propagation path for transmitting at least the wavelength band of the beam emitted by the transmitter, Reflect other bands to reduce the noise caused by ambient light to the receiver.

In some embodiments, the transmitter 203 may include a laser diode through which nanosecond laser pulses are emitted. Further, the laser pulse receiving time can be determined, for example, the laser pulse receiving time can be determined by detecting the rising edge time and/or the falling edge time of the electrical signal pulse. In this way, the distance measuring device 200 can calculate the TOF by using the pulse receiving time information and the pulse sending time information, so as to determine the distance between the probe 201 and the distance measuring device 200. The distance and azimuth detected by the distance measuring device 200 can be used for remote sensing, obstacle avoidance, surveying and mapping, modeling, navigation, and the like.

FIG. 9 shows a schematic diagram of another embodiment of the distance detection device 600. The distance detection device 600 is similar to the distance detection device 100 shown in FIG. 8. Compared with the embodiment shown in FIG. 8, the optical transceiver 610 of the distance detection device 600 of the embodiment shown in FIG. 9 includes a plurality of optical path changing elements 6061. -6063, change the optical path of the outgoing beam emitted by the light source 603 and the optical path of the return light, so that a collimating lens 604 with a longer focal length can be used, and the light source 603 and the detector 605 can be equivalent through multiple optical path changing elements 6061-6063 It is located at the focal position of the collimating lens 604. In this way, the optical path is folded by the optical path changing elements 6061-6063, so that the structure of the distance detection device 600 is compact, which is beneficial to miniaturization.

The light source 603 includes the laser package module structure of the first embodiment described above. The plurality of light path changing elements 6061-6063 may include mirrors, prisms, or other optical elements that change the light path. In the illustrated embodiment, the plurality of light path changing elements 6061-6063 includes a first light path changing element 6061, a second light path changing element 6062, and a second light path changing element 6063. The first light path changing element 6061 is arranged on the outside of the light-transmitting area, facing the light source 603 and the collimating lens 604, and is used to change the light path of the outgoing light emitted from the light-transmitting area of the laser diode package module so that it comes from all The laser pulse of the laser diode package module is incident on the collimating lens 604 in a direction substantially along the central axis of the collimating lens. For example, the first light path changing element 6061 is a mirror, and the first light path changing element 6061 is located on the center axis of the collimating lens, and is used to reflect the laser pulse emitted by the laser diode package module to the general edge. In the direction of the central axis of the collimating lens, taking the case where the reflecting surface is specifically an inclined surface prepared by etching the semiconductor using anisotropy as an example, the inclined surface prepared after etching is The included angle between the bottom surfaces of the semiconductor is generally 54.74°.

For example, the first optical path changing element 6061 of the reflector is placed obliquely with respect to the optical axis of the collimating lens 604, that is, deviating from the optical axis of the collimating lens 604, facing the light source 603 and the collimating lens 604, and is used to The outgoing light emitted from the light-transmitting area is reflected to the collimating lens 604. That is, the light source 603 emits a light beam diagonally downward, and the light beam reaches the first light path changing element 6061, and the first light path changing element 6061 reflects the light beam toward the collimating lens 604.

The center of the second light path changing element 6062 is provided with a light-transmitting area, such as a through hole 6064. The through hole 6064 is approximately located in the middle of the second optical path changing element 6062. The through hole 6064 has a trapezoidal shape. In other embodiments, the through hole 6064 may be rectangular, circular, or other shapes. Continuing to refer to FIG. 12, the second optical path changing element 6062 is located between the first optical path changing element 6061 and the collimating lens 604 and faces the collimating lens 604. The optical axis of the collimator lens 604 may pass through the through hole 6064. The light beam reflected by the first light path changing element 6061 passes through the through hole 6064 of the second light path changing element 6062, is projected to the collimating lens 604, and is collimated by the collimating lens 604.

In the illustrated embodiment, the detector 605 is located on the other side of the distance detection device 600 relative to the light source 603, and is used to convert the received optical signal into an electrical signal, and the electrical signal is used to measure the detection object. The distance to the distance detection device. The return light condensed by the collimator lens 604 passes through the second light path changing element 6062 and the third light path changing element 6063 and is condensed to the detector 605. The third light path changing element 6063 is located outside the collimating lens 604, located above the detector 605 close to the collimating lens 604, facing the second light path changing element 6062 and the detector 605, and is respectively connected to the second light path changing element 6062 and the The detectors 605 are arranged relatively. The return light condensed by the collimator lens 604 is reflected to the third light path changing element 6063 through the second light path changing element 6062, and the third light path changing element 6063 then reflects the return light to the detector 605.

The distance detection device implemented based on the packaged module structure according to the embodiment of the present invention can increase the transmission power, quickly respond to the rapid pulse drive signal, improve the reliability and accuracy, reduce the production cost and complexity, and improve the production effectiveness.

Although the exemplary embodiments have been described herein with reference to the accompanying drawings, it should be understood that the above-described exemplary embodiments are merely exemplary, and are not intended to limit the scope of the present invention thereto. Those of ordinary skill in the art can make various changes and modifications therein without departing from the scope and spirit of the present invention. All these changes and modifications are intended to be included within the scope of the present invention as claimed in the appended claims.

A person of ordinary skill in the art may realize that the units and algorithm steps of the examples described in combination with the embodiments disclosed herein can be implemented by electronic hardware or a combination of computer software and electronic hardware. Whether these functions are performed by hardware or software depends on the specific application and design constraint conditions of the technical solution. Professionals and technicians can use different methods for each specific application to implement the described functions, but such implementation should not be considered as going beyond the scope of the present invention.

In the several embodiments provided in this application, it should be understood that the disclosed device and method may be implemented in other ways. For example, the device embodiments described above are only illustrative. For example, the division of the units is only a logical function division, and there may be other divisions in actual implementation, for example, multiple units or components may be combined or It can be integrated into another device, or some features can be ignored or not implemented.

In the instructions provided here, a lot of specific details are explained. However, it can be understood that the embodiments of the present invention can be practiced without these specific details. In some instances, well-known methods, structures, and technologies are not shown in detail, so as not to obscure the understanding of this specification.

Similarly, it should be understood that in order to simplify the present invention and help understand one or more of the various aspects of the invention, in the description of the exemplary embodiments of the present invention, the various features of the present invention are sometimes grouped together into a single embodiment. , Or in its description. However, the method of the present invention should not be construed as reflecting the intention that the claimed invention requires more features than those explicitly stated in each claim. To be more precise, as reflected in the corresponding claims, the point of the invention is that the corresponding technical problems can be solved with features that are less than all the features of a single disclosed embodiment. Therefore, the claims following the specific embodiment are thus explicitly incorporated into the specific embodiment, wherein each claim itself serves as a separate embodiment of the present invention.

Those skilled in the art can understand that in addition to mutual exclusion between the features, any combination of all features disclosed in this specification (including the accompanying claims, abstract, and drawings) and any method or device disclosed in this manner can be used. Processes or units are combined. Unless expressly stated otherwise, each feature disclosed in this specification (including the accompanying claims, abstract and drawings) may be replaced by an alternative feature providing the same, equivalent or similar purpose.

In addition, those skilled in the art can understand that although some embodiments described herein include certain features included in other embodiments but not other features, the combination of features of different embodiments means that they are within the scope of the present invention. Within and form different embodiments. For example, in the claims, any one of the claimed embodiments can be used in any combination.

The various component embodiments of the present invention may be implemented by hardware, or by software modules running on one or more processors, or by a combination of them. Those skilled in the art should understand that a microprocessor or a digital signal processor (DSP) may be used in practice to implement some or all of the functions of some modules according to the embodiments of the present invention. The present invention can also be implemented as a device program (for example, a computer program and a computer program product) for executing part or all of the methods described herein. Such a program for realizing the present invention may be stored on a computer-readable medium, or may have the form of one or more signals. Such a signal can be downloaded from an Internet website, or provided on a carrier signal, or provided in any other form.

It should be noted that the above-mentioned embodiments illustrate rather than limit the present invention, and those skilled in the art can design alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses should not be constructed as a limitation to the claims. The invention can be implemented by means of hardware comprising several different elements and by means of a suitably programmed computer. In the unit claims that list several devices, several of these devices may be embodied in the same hardware item. The use of the words first, second, and third, etc. do not indicate any order. These words can be interpreted as names.

The above are only specific implementations or descriptions of specific implementations of the present invention. The protection scope of the present invention is not limited thereto. Any person skilled in the art can easily fall within the technical scope disclosed by the present invention. Any change or replacement should be included in the protection scope of the present invention. The protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

A laser diode packaging module, characterized in that the packaging module includes:

The substrate has a first surface and a second surface opposite to each other;

A cover body is arranged on the first surface of the substrate, and an accommodation space is formed between the substrate and the cover body;

The laser diode chip is arranged in the containing space and directly arranged on the first surface of the substrate;

The optical element is arranged on the first surface of the substrate;

Wherein, the distance between the laser diode chip and the optical element is configured such that the emitted light of the laser diode chip is emitted from the cover after changing the optical path by the optical element.
The package module according to claim 1, wherein the laser diode chip has a light exit, and the light exit includes a fast axis diverging in a first direction and a slow axis diverging in a second direction, the laser diode The distance between the chip and the optical element is configured such that the emitted light in the fast axis direction and the slow axis direction is emitted from the cover after changing the optical path through the optical element, wherein the first direction and the second direction The direction is vertical.
3. The package module according to claim 2, wherein the first direction is a direction extending along the thickness of the laser diode chip, and the second direction is a direction extending along the horizontal width of the laser diode chip.
The packaged module according to claim 2, wherein the divergence angle of the emitted light of the laser diode chip in the slow axis direction is 5°-15°, and/or, in the fast axis direction The divergence angle is 25°-35°.
The packaged module according to any one of claims 1 to 4, wherein the distance between the laser diode chip and the optical element is 50 μm-100 μm.
The package module according to claim 5, wherein the distance between the laser diode chip and the optical element is 50 μm-70 μm.
The package module according to claim 1, wherein the thickness of the laser diode chip is 100 μm-200 μm.
The package module according to claim 1, wherein the light outlet of the laser diode chip is arranged at the top position of the laser diode chip.
The packaged module according to claim 1, wherein the packaged module further comprises:

A slide table, the cutting table is arranged between the substrate and the laser diode chip, and the laser diode chip is arranged on a side of the cutting table close to the optical element.
The package module according to claim 9, characterized in that, on the side close to the optical element, the edge of the laser diode chip is aligned with the edge of the slide table, or the edge of the laser diode chip exceeds all the edges. The edge of the slide table is within 30 μm, or the edge of the slide table exceeds the edge of the laser diode chip within 50 μm.
The package module according to claim 1, wherein the optical element comprises a reflecting mirror, the reflecting mirror comprises at least one reflecting surface, and the emitted light of the laser diode chip is reflected by the reflecting surface and then emitted.
The package module according to claim 11, wherein the reflective surface is an inclined surface prepared by etching a semiconductor using anisotropy, or the reflective surface includes an anisotropic surface formed on the semiconductor. The reflective film is plated on the inclined surface prepared by etching.
The packaged module according to claim 12, wherein the semiconductor comprises a semiconductor wafer.
The packaged module according to claim 12, wherein the semiconductor is silicon, and the angle between the inclined surface and the bottom surface of the semiconductor is approximately 54.74°.
The package module according to claim 12, wherein a groove is provided at the sharp corner of the bottom surface of the reflector.
The package module according to claim 15, wherein the depth of the groove is within 20 μm.
The package module according to claim 11, wherein the reflecting mirror comprises a glass prism, and the included angle between the reflecting surface and the horizontal bottom surface where the reflecting mirror is located is 30-60°.
The package module according to claim 17, wherein the angle between the reflecting surface and the horizontal bottom surface where the reflecting mirror is located is 45°.
The packaged module according to claim 1, wherein the emitted light of the laser diode chip changes its optical path through the optical element and is in a direction at a certain angle with the first surface of the substrate of the laser diode packaged module. Laser pulses are emitted.
The package module according to claim 1, wherein a light-transmitting area is at least partially provided on the cover, and the light emitted from the laser diode chip is emitted from the light-transmitting area after changing the optical path by the optical element. Get out.
The package module according to claim 20, wherein the light-transmitting area is provided on the top surface of the cover, and the top surface is opposite to the first surface, and the emitted light of the laser diode chip Emitted through the light-transmitting area.
The package module according to claim 21, wherein the cover comprises a U-shaped cover body with a window, and a light-transmitting plate arranged on the window to form the light-transmitting area, and the laser diode The light emitted by the chip is emitted through the light-transmitting plate; or the cover body is a plate-like structure with all light-transmitting.
The package module according to claim 21, wherein the cover body is fixedly arranged on the first surface of the substrate by welding.
The package module according to claim 21, wherein the material of the cover body includes metal, resin or ceramic.
The package module of claim 1, wherein the laser diode chip is mounted on the first surface of the substrate.
The package module according to claim 1, wherein the laser diode chip comprises a first electrode and a second electrode arranged opposite to each other, and the surface on which the first electrode is located is mounted on the first surface of the substrate on.
The package module of claim 26, wherein the first electrode is mounted on the first surface of the substrate through a conductive adhesive layer.
The package module of claim 26, wherein the second electrode is electrically connected to the substrate through a wire.
The package module according to claim 26, wherein a plurality of the laser diode chips are arranged side by side in the third direction of the first surface to form a laser diode chip array, and the output of the laser diode chip array The incident light is emitted from the cover after changing the optical path through the optical element.
The package module according to claim 29, wherein a plurality of the laser diode chip arrays and a plurality of the optical diode chip arrays arranged opposite to the laser diode chip array are arranged in a fourth direction of the first surface. Element, wherein the third direction is perpendicular to the fourth direction.
The package module according to claim 29, wherein the second electrodes of the plurality of laser diodes opposite to the reflective surface in the laser diode chip array are electrically connected to the substrate through wires The same pad.
The package module according to claim 1, wherein the length of the optical element used to change the optical path of the exit light on the first surface is 800 μm-1000 μm.
The package module according to claim 27, wherein the area of the conductive adhesive layer is larger than the area of the bottom surface of the laser diode chip; and/or

The conductive adhesive layer is electrically connected to the pad on the substrate through a wire, so as to lead out the first electrode.
The package module according to claim 1, wherein the optical element is mounted on the first surface of the substrate through a conductive adhesive layer.
The package module according to any one of claims 27, 33 and 34, wherein the material of the conductive adhesive layer comprises conductive silver paste, solder or conductive chip connection film.
The packaged module according to claim 1, wherein the packaged module further comprises a driving chip for controlling the emission of the laser diode chip, the driving chip is arranged in the containing space, wherein the driving chip The chip is mounted on the first surface of the substrate.
The packaged module according to claim 1, wherein the substrate comprises a PCB substrate or a ceramic substrate.
A distance detection device, characterized in that it comprises:

The laser diode package module according to any one of claims 1 to 37, which is used to emit laser pulses in a direction at a certain angle with the first surface of the substrate of the laser diode package module;

The collimating lens is arranged on the outside of the cover and is used to collimate the light emitted from the cover;

The first optical path changing element is arranged on the outside of the cover, and is used to change the optical path of the exit light emitted from the cover so that the laser pulse from the laser diode package module is substantially along the The direction of the center axis of the collimating lens is incident on the collimating lens.
The distance detection device according to claim 38, wherein the first optical path changing element comprises:

The first reflector, the first reflector deviates from the optical axis of the collimating lens, and is used for reflecting the outgoing light emitted from the cover to the collimating lens.
The distance detection device according to claim 39, wherein the laser diode package module is located on one side of the center axis of the collimating lens, and the first surface of the substrate in the laser diode package module Substantially parallel to the central axis of the collimating lens;

The first reflecting mirror is located on the central axis of the collimating lens, and is used for reflecting the laser pulse emitted by the laser diode package module to a direction substantially along the central axis of the collimating lens.
The distance detection device according to claim 39, wherein the collimating lens is also used to condense at least a part of the return light reflected by the detection object;

The distance detection device further includes:

A second reflector, a third reflector and a detector with a light-transmitting area are arranged in the center;

The second reflector is arranged between the collimating lens and the first reflector, allows the light beam reflected by the first reflector to pass through, and is used to converge the collimating lens. The light is reflected to the third reflecting mirror;

The third reflector is respectively arranged opposite to the second reflector and the detector, and is used to reflect the return light reflected by the second reflector to the detector;

The detector is used to convert the received optical signal into an electrical signal, and the electrical signal is used to measure the distance between the detection object and the distance detection device.
An electronic device, characterized by comprising the laser diode packaging module according to any one of claims 1 to 37, the electronic device comprising an unmanned aerial vehicle, a car or a robot.