CN218040201U - Surface emitting laser chip and optical device - Google Patents

Abstract

The utility model relates to a surface-emitting laser chip and an optical device. The surface-emitting laser chip includes a substrate, a plurality of surface-emitting lasers, a temperature measuring unit and a metal pipe cap, and the metal pipe cap is arranged on the surface-emitting laser and the measuring The temperature unit is connected to the substrate, and the connection circuit of the surface-emitting laser and the connection circuit of the temperature measuring element are connected to the ground wire of the substrate. The surface-emitting laser chip is mounted on the same substrate by bonding multiple surface-emitting lasers and temperature measurement units for common heat dissipation, and is packaged by a metal tube cap with glass, so that the temperature measurement unit and the surface-emitting laser can be placed at close range are in the same sealed space to ensure the temperature consistency between the surface-emitting laser and the temperature measurement unit, thereby improving the accuracy of temperature measurement of the surface-emitting laser; in addition, the surface-emitting laser and the temperature measurement unit are grounded through the grounding circuit of the substrate, that is The grounding circuit of the surface-emitting laser and the grounding circuit of the temperature measuring unit can be simplified, thereby reducing the production cost.

Description

Surface-emitting laser chip and optical device

technical field

The utility model relates to the technical field of surface emitting laser chip temperature measurement, in particular to a surface emitting laser chip and an optical device.

Background technique

With the development of science and technology, the information transmission rate is getting higher and higher, especially in the field of optical communication, the integration of optical devices is also getting higher and higher. For example, the common vertical cavity surface emitting laser (Vertical Cavity Surface Emitting Laser, or VCSEL), the speed is getting higher and higher, the size is getting smaller and smaller, there are various specifications such as single-channel and 4-channel arrays, and the integration level is getting higher and higher. Therefore, designers are paying more and more attention to the actual temperature of VCSEL, one is used for VCSEL aging screening, and the other is used for real-time monitoring of VCSEL temperature, and then to optimize related designs.

At present, the common methods of testing VCSEL temperature are:

1. The reference value calculated by thermal simulation;

2. The temperature of the module shell is used as an approximate reference;

3. Use the module to drive the chip temperature as an approximate reference;

4. Approximate reference for testing the backside temperature of the VCSEL.

However, the above methods of testing the VCSEL temperature are all approximate reference values obtained by measuring the temperature of the adjacent parts of the chip through the temperature measuring element. The temperature measuring element and the chip are not in the same space. When the temperature of the chip is transferred to the adjacent parts , the temperature has been partially lost, that is, the error range of the chip measurement using the above method is relatively large, and it is difficult to accurately detect the VCSEL temperature.

Therefore, the prior art still needs to be improved and developed.

Utility model content

The purpose of the embodiments of the present invention is to provide a surface emitting laser chip and an optical device, so as to solve the technical problem of low temperature measurement accuracy of the existing surface emitting laser.

The technical scheme of the utility model embodiment is as follows:

An embodiment of the utility model provides a surface-emitting laser chip, including:

a substrate provided with a conductive layer forming a ground circuit

A plurality of surface-emitting lasers are attached to the substrate, and the plurality of surface-emitting lasers are electrically connected to the substrate;

A temperature measurement unit is attached to the substrate, and the temperature measurement unit is electrically connected to the substrate;

Metal tube cap with glass on top;

Wherein, a plurality of the surface emitting lasers and the temperature measuring unit are arranged in a row in turn, the metal tube cap is arranged on the surface emitting laser and the temperature measuring unit and connected to the substrate, and the surface emitting laser and the temperature measuring element ground through the ground circuit.

Further, in a preferred solution of some embodiments, there are multiple surface-emitting lasers, and the multiple surface-emitting lasers are arranged in a row; and along the arrangement direction of the multiple surface-emitting lasers, the temperature measurement unit It is arranged on one side of the plurality of surface-emitting lasers.

Further, in a preferred solution of some embodiments, the size of the temperature measurement unit is smaller than or equal to the size of the surface emitting laser.

Further, in a preferred solution of some embodiments, the distance from the temperature measuring unit to the surface emitting laser is between 10um and 50um.

Further, in a preferred solution of some embodiments, the size of the surface emitting laser is 220um×200um×220um, and the size of the temperature measurement unit is 200um×200um×220um.

Further, in a preferred solution of some embodiments, the substrate is provided with a first pin and a second pin, and the surface-emitting laser is fixedly connected to the substrate by bonding and is electrically connected to the first pin ; The temperature measurement unit is fixedly connected to the substrate through a bonding method, and is electrically connected to the second pin.

Further, in a preferred solution of some embodiments, the temperature measuring unit is a chip-type thermistor.

Further, in a preferred solution of some embodiments, the substrate is an aluminum nitride bottom plate.

The embodiment of the present invention also provides an optical device, including a PCB circuit board and the above-mentioned surface-emitting laser chip, and the surface-emitting laser chip is fixedly arranged on the PCB circuit board and electrically connected to the PCB circuit board.

Further, in a preferred solution of some embodiments, or the optical device includes a conductive adhesive layer and a glue-drop packaging layer, the surface reflection laser chip is fixedly connected to the PCB circuit board through a conductive glue layer, and the glue-drop packaging layer The cover is arranged on the surface-emitting laser chip and fixedly connected with the PCB circuit board.

Compared with the prior art, the surface-emitting laser chip and the optical device provided by the embodiment of the utility model mainly have the following beneficial effects:

The surface-emitting laser chip is mounted on the same substrate by bonding multiple surface-emitting lasers and temperature measurement units for common heat dissipation, and is packaged by a metal tube cap with glass, so that the temperature measurement unit and the surface-emitting laser can be placed in close proximity are in the same sealed space to ensure the temperature consistency between the surface-emitting laser and the temperature measurement unit, thereby improving the accuracy of temperature measurement of the surface-emitting laser; in addition, the surface-emitting laser and the temperature measurement unit are grounded through the grounding circuit of the substrate, that is The grounding circuit of the surface-emitting laser and the grounding circuit of the temperature measuring unit can be simplified, thereby reducing the production cost.

Description of drawings

In order to illustrate the scheme in the utility model more clearly, a brief introduction will be made to the accompanying drawings that need to be used in the description of the embodiments below. Obviously, the accompanying drawings in the following description are some embodiments of the utility model. Those of ordinary skill in the art can also obtain other drawings based on these drawings without any creative effort. in:

Fig. 1 is a schematic structural view of a surface-emitting laser chip in one embodiment of the present invention (the metal cap is omitted);

Fig. 2 is a schematic structural diagram of an optical device in an embodiment of the present invention.

The labels in the accompanying drawings are as follows:

100. Surface emitting laser chip; 200. PCB circuit board;

1. Substrate; 2. Surface emitting laser; 3. Temperature measurement unit; 4. Metal tube cap;

41. Metal pipe; 42. Glass.

detailed description

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field of the present invention; the terms used in the description herein are only for the purpose of describing specific embodiments, not intended to To limit the present invention, for example, the terms "length", "width", "upper", "lower", "left", "right", "front", "rear", "vertical", "horizontal", The orientations or positions indicated by "top", "bottom", "inner" and "outer" are based on the orientations or positions shown in the drawings, and are for convenience of description only, and should not be construed as limitations on the technical solution.

The terms "comprise" and "have" in the specification and claims of the utility model and the description of the above-mentioned drawings, as well as any variations thereof, are intended to cover non-exclusive inclusion; the specification and claims of the utility model or the above-mentioned appended The terms "first", "second", etc. in the drawings are used to distinguish different objects, not to describe a specific order. "Plurality" means two or more, unless otherwise clearly and specifically defined.

In the specification and claims of the utility model and the description of the above drawings, when an element is referred to as "fixed on" or "installed on" or "set on" or "connected to" another element, it may be directly or indirectly on that other element. For example, when an element is referred to as being "connected to" another element, it can be directly or indirectly connected to the other element.

Furthermore, reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the present invention. The occurrences of this phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. It is understood explicitly and implicitly by those skilled in the art that the embodiments described herein can be combined with other embodiments.

The embodiment of the present invention provides a surface-emitting laser chip 100, please refer to Fig. 1 and Fig. 2, including a substrate 1, at least one surface-emitting laser 2, a temperature measuring unit 3 and a metal cap 4, the surface-emitting laser 2 is set On the substrate 1 and electrically connected to the substrate 1; the temperature measurement unit 3 is arranged on the substrate 1 and electrically connected to the substrate 1; the metal tube cap 4 is set on the surface emitting laser 2 and the temperature measurement unit 3 and connected to the substrate 1. Wherein, the substrate is provided with a conductive layer, and the conductive layer forms a grounding circuit, and the surface emitting laser 2 and the temperature measuring element 3 are grounded through the grounding circuit.

It should be noted that a conductive layer is provided on the substrate 1 to form a connection circuit, and the surface-emitting laser 2 and the temperature measurement unit 3 are electrically connected to the conductive layer on the substrate 1; wherein the temperature measurement unit 3 passes The connection circuit of the conductive layer is connected to the external measurement circuit. In this embodiment, the metal tube cap 4 includes a metal tube 41 and a glass 42, and the glass 42 is arranged on the top of the metal tube, so that the light emitted by the surface-emitting laser 2 can be output normally, ensuring the surface-emitting laser chip 100 Normal use.

In summary, compared with the prior art, the surface-emitting laser chip 100 is mounted on the same substrate 1 by laminating multiple surface-emitting lasers 2 and temperature measurement units 3, and is packaged by a metal cap 4 provided with a glass 42. , multiple temperature measuring units 3 and surface-emitting lasers 2 can be placed in the same sealed space to ensure the temperature consistency between the surface-emitting laser and the temperature measuring unit, thereby improving the accuracy of temperature measurement of the surface-emitting laser; in addition, the surface-emitting The laser 2 and the temperature measuring unit 3 are grounded through the grounding circuit of the substrate, which simplifies the grounding circuit of the surface emitting laser and the grounding circuit of the temperature measuring unit, thereby reducing the production cost.

Further, referring to FIG. 1 and FIG. 2 , there are multiple surface-emitting lasers 2 , and multiple surface-emitting lasers 2 and temperature measuring units 3 are arranged in a row in sequence. By arranging a plurality of surface-emitting lasers 2 and temperature measurement units 3 in a row, the overall shape of the surface-emitting laser chip 100 can be relatively regular, which is convenient for storage, transportation and use, and at the same time can facilitate multiple surface-emitting lasers 2 and temperature measurement. The wiring of the unit 3 reduces the complexity of the connection circuit on the substrate 1 and improves the production efficiency of the substrate 1 .

In another embodiment, the temperature measurement unit 3 can also be arranged on one side of the surface emitting laser 2 along the direction perpendicular to the arrangement of the plurality of surface emitting lasers 2 , so as to realize the function of temperature measurement.

Embodiment 1 of the surface-emitting laser chip 100 of the present invention

In order to enable those skilled in the art to better understand the solution of the utility model, the technical solution in Embodiment 1 of the utility model will be clearly and completely described below in conjunction with accompanying drawings 1 and 2 .

Further, please refer to FIG. 1 and FIG. 2 , the size of the temperature measurement unit 3 is smaller than or equal to the size of the surface emitting laser 2 . In actual production, the function of the substrate 1 is to carry and fix the surface-emitting laser 2 and the temperature measurement unit 3. Therefore, the size of the surface-emitting laser chip 100 is generally determined by the size of the substrate 1; The storage and carrying of the emitting laser chip 100, its overall shape is relatively regular square, when the size of the temperature measurement unit 3 is larger than the size of the surface emitting laser 2, the substrate 1 not only needs to increase the area of the temperature measurement unit 3, At the same time, it is also necessary to adjust the size of the part of the substrate 1 carrying multiple surface-emitting lasers 2 , resulting in an excessively large area of the substrate 1 . Now, by limiting the size of the temperature measuring unit 3 to be smaller than or equal to the size of the surface emitting laser 2, it is only necessary to increase the area of the substrate 1 carrying the temperature measuring unit 3, without increasing the area of the substrate carrying multiple surface emitting lasers 2. The size and area can effectively limit the size of the surface emitting laser chip 100 to ensure the effect of use.

Further, the distance between the temperature measurement unit 3 and the surface emitting laser 2 is between 10um and 50um. In this embodiment, the surface-emitting laser 2 and the temperature measurement unit 3 are mainly fixed on the substrate 1 by bonding, and the distance between the temperature measurement unit 3 and the surface-emitting laser 2 is limited to 10um to 50um, so that The structure of the surface-emitting laser chip is more compact, the overall size is smaller, the distance is further, and the measurement accuracy is higher. At the same time, the interaction between the surface-emitting laser 2 and the temperature measurement unit 3 is prevented to ensure the efficiency of processing.

In this embodiment, the size of the surface emitting laser 2 is 220um×200um×220um, and the size of the temperature measuring unit 3 is 200um×200um×220um. Wherein, the number of the surface-emitting lasers 2 is four, and the minimum size of the surface-emitting laser chip can reach 1200um×220um×225um. In this embodiment, by limiting the size of the surface-emitting laser 2 and the temperature measurement unit 3 , it is possible to reduce the size of the surface-emitting laser chip to ensure the use effect under the premise that the surface-emitting laser chip has high temperature measurement accuracy.

Further, the substrate 1 is provided with a first pin (not shown in the figure) and a second pin (not shown in the figure), and the surface-emitting laser 2 is fixedly connected to the substrate 1 by bonding, and electrically connected to the first pin; the temperature measuring unit 3 is fixedly connected to the substrate 1 by bonding, and electrically connected to the second pin. In this embodiment, the surface-emitting laser 2 and the temperature measurement unit 3 are respectively fixed by welding with the electrodes on the substrate 1 through independent bonding wires, and are respectively connected to the first pin and the second tube through the conductive layer on the substrate 1. The feet are electrically connected, that is, the control circuit of the surface-emitting laser 2 and the test circuit of the temperature measurement unit 3 are set relatively independently, which can reduce the mutual interference between the circuits of the surface-emitting laser 2 and the temperature measurement unit 3, and ensure that each The normal implementation of the function. Wherein, the first pin is connected through an external circuit to realize the control of multiple surface emitting lasers 2 , and the temperature measuring unit 3 is connected to the measurement circuit to measure the temperature of the surface emitting lasers 2 .

Further, please refer to FIG. 1 and FIG. 2 , the temperature measuring unit 3 is a chip-type thermistor. Wherein, the chip type thermistor has the advantages of small size and high measurement accuracy. In this embodiment, the chip type thermistor is a negative temperature coefficient thermistor (NTC). Specifically, the measuring circuit is a voltmeter, and its purpose is to calculate and measure the resistance value of the chip type thermistor, and then obtain the temperature of the temperature measuring unit 3 according to the corresponding thermistor (NTC) temperature characteristic curve, that is, The temperature of the surface generating laser 2 in the same environment is known. In another embodiment, a positive temperature coefficient thermistor can also be used to measure the temperature.

Further, the substrate 1 is an aluminum nitride bottom plate. Among them, the advantages of using the aluminum nitride bottom include: 1. High thermal conductivity, which is beneficial to the heat dissipation of the surface-emitting laser chip; 2. Small expansion coefficient, which can achieve a good combination with the surface-emitting laser 2; 3. Good insulation performance , the energy gap width is 6.2eV, no insulation treatment is required, and the process is simplified; 4. It has high hardness and strength, and good mechanical properties; 5. It has good chemical stability and high temperature resistance.

In this embodiment, the specific production process of the surface-emitting laser chip 100 is as follows:

1) Substrate 1: Aluminum nitride substrate is used, sintered in an oxidizing atmosphere at 600-650 degrees Celsius, metallized with low-temperature silver paste, and the through-holes connecting internal and external circuits are filled with paste;

2) Glass 42: use flat k9 glass with a wavelength of 400-1200nm and a transmittance of 92.7%, cut it into a wafer, print low-temperature glass paste on the surrounding, and dry it for later use;

3) Metal tube 41: A metal tube cap with a light window is punched out of a Kovar alloy sheet, for use;

4) Metal tube with glass (metal tube cap 4): place the glass on the top of the metal tube and seal it with low-temperature glass solder hyg750. The sealing process: preheating zone rt～100°C for 10 minutes, heating zone 100～350°C for 10 minutes , Sintering zone 350～580℃ for 15min, cooling zone 580～350℃15min, cooling zone 350～100℃10min;

5) Nickel-plating and gold-plating the aluminum nitride substrate and the metal pipe cap for subsequent use;

6) Encapsulation of surface emitting laser 2 and temperature measuring unit 3: the surface emitting laser and temperature measuring unit are eutectically fixed on the substrate 1, and the surface emitting laser 2 and temperature measuring unit 3 are connected to the electrodes on the substrate 1 by bonding process In the electrode of the pad, the packaging is completed, and the metal tube 42 with glass 41 is placed on the surface-emitting laser 2 and the temperature measurement unit 3, and the metal tube with glass is sealed and fixed on the substrate 1 by soldering process, and the completion encapsulation.

Based on the above-mentioned surface-emitting laser chip 100, please refer to FIG. 1 and FIG. 2, the embodiment of the present utility model also provides an optical device, wherein the optical device includes a PCB circuit board 200, such as the above-mentioned surface-emitting laser chip 100 , the surface-emitting laser chip is fixedly arranged on the PCB circuit board and electrically connected with the PCB circuit board.

To sum up, compared with the prior art, the optical device has at least the following beneficial effects: the optical device adopts the above-mentioned surface-emitting laser chip 100, wherein the surface-emitting laser chip 100 is arranged on the surface-emitting laser 2 and the temperature measurement unit 3 On the same substrate 1 and packaged by a metal cap 4 provided with glass 42, the temperature measurement unit 3 and the surface-emitting laser 2 can be placed in the same sealed space, effectively improving the measurement accuracy; in addition, the surface-emitting laser 2 The connection circuit of the temperature measurement unit 3 and the connection circuit of the temperature measurement unit 3 are connected to the ground wire of the substrate 1, and the surface emitting laser 2 and the temperature measurement unit 3 can jointly dissipate heat through the ground circuit of the substrate, so that the temperature of the temperature measurement unit 3 is closer to The temperature of the surface-emitting laser 2 is improved, thereby improving the accuracy of temperature measurement of the surface-emitting laser 2 .

Further, the optical device also includes a conductive adhesive layer (not shown in the figure), and a glue-drop sealing layer (not shown in the figure), and the surface reflection laser chip 100 is fixed to the PCB circuit board through the conductive adhesive layer connected, the glue encapsulation layer is covered on the surface emitting laser chip 100 and fixedly connected to the PCB circuit board. Specifically, the conductive adhesive layer is silver-containing epoxy resin adhesive, and the epoxy encapsulation layer is epoxy resin adhesive or silane resin.

Of course, in other embodiments, the surface emitting laser chip 100 can also be directly fixed on the PCB circuit board 200 by bonding, and electrically connected with the PCB circuit board 200 .

The above descriptions are only preferred embodiments of the present utility model, and are not intended to limit the present utility model. For those skilled in the art, the utility model can have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present utility model shall be included within the scope of the claims of the present utility model.

Claims (9)

1. A surface-emitting laser chip, characterized in that, comprising: a substrate provided with a conductive layer forming a ground circuit A plurality of surface-emitting lasers are attached to the substrate, and the plurality of surface-emitting lasers are electrically connected to the substrate; A temperature measurement unit is attached to the substrate, and the temperature measurement unit is electrically connected to the substrate; Metal tube cap with glass on top; Wherein, a plurality of the surface emitting lasers and the temperature measuring unit are arranged in a row in turn, the metal tube cap is arranged on the surface emitting laser and the temperature measuring unit and connected to the substrate, and the surface emitting laser and the temperature measuring element ground through the ground circuit. 2 . The surface emitting laser chip according to claim 1 , wherein the size of the temperature measuring unit is smaller than or equal to the size of the surface emitting laser. 3 . 3 . The surface emitting laser chip according to claim 2 , wherein the distance from the temperature measurement unit to the surface emitting laser is between 10 um and 50 um. 4 . The surface emitting laser chip according to claim 3 , wherein the size of the surface emitting laser is 220um×200um×220um, and the size of the temperature measurement unit is 200um×200um×220um. 5. The surface-emitting laser chip according to any one of claims 1-4, wherein the substrate is provided with a first pin and a second pin, and the surface-emitting laser is fixed to the substrate by bonding connected, and electrically connected to the first pin; the temperature measuring unit is fixedly connected to the substrate by bonding, and electrically connected to the second pin. 6. The surface-emitting laser chip according to claim 5, wherein the temperature measuring unit is a chip-type thermistor. 7. The surface emitting laser chip according to claim 6, wherein the substrate is an aluminum nitride bottom plate. 8. An optical device, characterized in that it comprises a PCB circuit board and the surface-emitting laser chip as claimed in any one of claims 1-7, the surface-emitting laser chip is fixedly arranged on the PCB circuit board and connected to the PCB circuit board electrical connection. 9. The optical device according to claim 8, wherein the surface-emitting laser chip is fixed on the PCB circuit board by binding; Or the optical device includes a conductive adhesive layer and a glue-dipping encapsulation layer, the surface-emitting laser chip is fixedly connected to the PCB circuit board through the conductive adhesive layer, and the adhesive-dipping encapsulation layer is covered on the surface-emitting laser chip and connected to the PCB circuit Board fixed connections.

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