CN215119534U

CN215119534U - Laser device

Info

Publication number: CN215119534U
Application number: CN202121080172.6U
Authority: CN
Inventors: 王刚; 周艳妮; 王鹏; 贺喆; 李勇
Original assignee: Focuslight Technologies Inc
Current assignee: Focuslight Technologies Inc
Priority date: 2021-05-19
Filing date: 2021-05-19
Publication date: 2021-12-10
Anticipated expiration: 2031-05-19

Abstract

The application provides a laser device, relates to semiconductor photon technical field, including the substrate, establish the photon chip on the substrate, be located the optical component and the temperature controller of photon chip emission direction, substrate and optical component all establish on temperature controller, and optical component includes support piece and the optical element who is connected with support piece, and support piece passes through the welding layer and the temperature controller is connected. The photonic chip, the substrate and the optical assembly are all arranged on the temperature controller, so that the working performance of each device can be well matched when each device is at the same temperature, the consistency of the working performance of each device can be ensured, the optical characteristics of the optical assembly can be ensured, the deviation in the high-temperature and low-temperature change process is small, and the light spot quality is ensured. Fix support piece on temperature controller through the welding, support piece stability on temperature controller is better, reduces the position excursion degree of optical assembly on temperature controller, and optical assembly is more stable, further reduces the influence to the light spot quality.

Description

Laser device

Technical Field

The application relates to the technical field of semiconductor photons, in particular to a laser.

Background

Semiconductor photonic technology is often applied in the fields of high-frequency low-pulse laser devices, vehicle-mounted radar laser devices, and the like.

In application, one method is to mount the photonic chip directly on the ceramic laser circuit board, so that the parasitic inductance and heat dissipation of the obtained laser are optimal. However, the problem of power attenuation of the semiconductor laser at high temperature and the problem of index deviation caused by position change of the optical element at high temperature cannot be solved. The other design method is that the chip is used as a small module, the laser circuit board is placed outside the laser for supplying power, but the temperature of the current design method is not controllable for the optical element. At high temperatures, variations in the optical characteristics of the optical element are likely to occur, which in turn leads to a reduction in the quality of the optical spot.

SUMMERY OF THE UTILITY MODEL

An object of the embodiments of the present application is to provide a laser, which can solve the problem of deviation of optical characteristics in a high temperature process.

In one aspect of the embodiment of the present application, a laser is provided, the laser includes a substrate, a photonic chip on the substrate, an optical component and a temperature controller located in the emission direction of the photonic chip, the substrate and the optical component are all set on the temperature controller, the optical component includes a support and an optical element connected with the support, the support passes through a welding layer and the temperature controller is connected.

The module formed by the photonic chip and the substrate and the optical component are both arranged on the temperature controller, so that the optical characteristic of the optical component is ensured to have smaller deviation in the high-low temperature change process, and the light spot quality is ensured.

The optical element is fixed through the support, and light emitted by the photonic chip is emitted through the optical element; the support piece is arranged on the temperature controller, and the support piece and the temperature controller are connected through a welding layer.

The stability of support piece on temperature controller is better for the mode of welding, and that is optical element's stability is better, and through the mode of welding, the laser instrument generates heat at the during operation, reduces the drift degree of optical assembly on temperature controller, makes optical assembly more stable, further reduces the influence to the light spot quality.

Optionally, matching the thermal expansion coefficients of the surface material of the temperature controller, the material of the substrate and the material of the support can reduce the effect of high temperature thermal expansion of the materials on the quality of the spot.

Optionally, the laser further comprises a temperature sensor disposed on the substrate, the temperature sensor being electrically connected to the temperature controller.

Optionally, the laser further includes a laser circuit board, a pad is disposed on the laser circuit board, and the photonic chip and the pad are electrically connected by a bonding wire.

The laser circuit board is provided with a bonding pad, the bonding pad is conducted with the laser circuit board, and the photonic chip is electrically connected with the bonding pad through a bonding wire so as to conduct the photonic chip and the laser circuit board.

Optionally, a heat sink is arranged at the bottom of the laser circuit board, the laser circuit board is subjected to heat dissipation through the heat sink, the photonic chip and the optical element are controlled in temperature through a temperature controller, and the heat dissipation and the temperature control are separately arranged, so that the reliability of the laser is improved.

Optionally, the positive electrode of the photonic chip is electrically connected to the positive pad through at least one positive bonding wire, and the negative electrode of the photonic chip is electrically connected to the negative pad through at least one negative bonding wire.

The photonic chip comprises a positive electrode and a negative electrode, the bonding pads comprise a positive bonding pad and a negative bonding pad, the positive electrode of the photonic chip is correspondingly connected with the positive bonding pad, and the negative electrode of the photonic chip is correspondingly connected with the negative bonding pad.

Optionally, the negative pad is located within a circumference centered on a negative electrode of the photonic chip. The negative electrode of the photonic chip is taken as the center, and the distance between the negative electrode of the photonic chip and the negative electrode bonding pad is taken as the radius direction of the circumference, so that the parasitic inductance is minimum within the range of the ring by taking the bonding part of the photonic chip as the center of a circle and the shortest bonding path as the radius.

Optionally, the positive electrode bonding wire and the negative electrode bonding wire are respectively located in two different planes. The crosstalk between the positive electrode and the negative electrode can be reduced, the inductance is reduced, the power is improved, the power attenuation problem of the short pulse laser at high temperature and the power low problem caused by parasitic inductance are solved, and the reliability of the laser is improved.

Optionally, the positive electrode bonding wire and the negative electrode bonding wire include a plurality of bonding wires, the negative electrode bonding wires are parallel to each other, one end of each of the positive electrode bonding wires extends in a direction toward the positive electrode pad, the other end of each of the positive electrode bonding wires diverges outward and is arranged in a sector shape, and an area formed by the positive electrode bonding wires covers an area formed by the negative electrode bonding wires.

Optionally, the positive bonding wire is located on a side of the negative bonding wire away from the substrate. The negative bonding wire is close to the substrate, the positive bonding wire is far away from the substrate, and the positive bonding wire covers the negative bonding wire, so that the mutual crosstalk between the positive electrode and the negative electrode can be reduced, and the parasitic inductance is reduced.

According to the laser provided by the embodiment of the application, the photonic chip is arranged on the substrate, the photonic chip and the substrate are both arranged on the temperature controller, meanwhile, the optical component is also arranged on the temperature controller, and the optical component is positioned in the emission direction of the photonic chip; optical assembly includes support piece and the optical element who is connected with support piece, support piece passes through the welded layer and is connected with temperature controller, with the photon chip, substrate and optical assembly all install on temperature controller, so, each device is all installed on temperature controller, can guarantee that each device is under same temperature, the working property of each device can better matching, the uniformity of each device working property can be guaranteed, and optical assembly's optical characteristic can be guaranteed, deviation in high and low temperature change process is less, and then guarantee facula quality. Simultaneously, fix support piece on temperature controller through the welding, the welded mode is compared in the advantage of bonding mode: 1. the welding material for welding has smaller CTE, and the welding material has smaller self-offset when the temperature changes; 2. the shear strength of the solder is higher. The stability of support piece on temperature controller is better, and that is to say optical element's stability is better, and through the welded mode, the laser instrument heats at the during operation, reduces the offset degree of optical assembly on temperature controller, makes optical assembly more stable, further reduces the influence to the spot quality.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are required to be used in the embodiments of the present application will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present application and therefore should not be considered as limiting the scope, and that those skilled in the art can also obtain other related drawings based on the drawings without inventive efforts.

Fig. 1 is a schematic structural diagram of a laser provided in an embodiment of the present application;

FIG. 2 is a schematic diagram of a partial structure of a laser according to an embodiment of the present disclosure;

FIG. 3 is a second schematic diagram of a partial structure of a laser according to an embodiment of the present disclosure;

FIG. 4 is a third schematic view of a partial structure of a laser according to an embodiment of the present disclosure;

fig. 5 is a fourth schematic view of a partial structure of a laser according to an embodiment of the present application.

Icon: 1-a photonic chip; 11-positive electrode; 12-a negative electrode; 110-positive bond wire; 120-negative bond wire; 2-laser circuit board; 21-positive electrode pad; 22-negative electrode pad; 3-a substrate; 4-heat sink; 5-a bottom plate; 6-temperature controller; 7-an optical element; 8-a support member; a-inductance range.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application.

In the description of the present application, it should be noted that the terms "inside", "outside", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings or orientations or positional relationships that the products of the application usually place when using, and are only used for convenience in describing the present application and simplifying the description, but do not indicate or imply that the devices or elements that are referred to must have a specific orientation, be constructed in a specific orientation, and operate, and thus, should not be construed as limiting the present application. Furthermore, the terms "first," "second," and the like are used merely to distinguish one description from another, and are not to be construed as indicating or implying relative importance.

It should also be noted that, unless expressly stated or limited otherwise, the terms "disposed" and "connected" are to be construed broadly, e.g., as meaning fixedly connected, detachably connected, or integrally connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present application can be understood in a specific case by those of ordinary skill in the art.

Semiconductor photonic technology is often applied in the fields of high-frequency low-pulse laser devices, vehicle-mounted radar laser devices, and the like. One current approach involves directly mounting a photonic chip onto a ceramic laser circuit board (PCB), so that the resulting laser has optimal inductance and heat dissipation. However, the problem of power attenuation of the semiconductor laser at high temperature and the problem of index deviation caused by position change of the optical element at high temperature cannot be solved. And the difficulty and cost of controlling the temperature of the whole PCB are increased. Another design method is to use the chip as a small module, and place the laser circuit board outside the laser for power supply. This is less costly but has higher parasitic inductance resulting in lower power. With the increasing market demand for short-pulse high-power semiconductor lasers, both methods cannot simultaneously meet the requirements of low parasitic inductance and independent temperature control. In the case of optical elements, the temperature of the optical elements is not controlled by current design methods, which easily causes deviation (e.g., position deviation) of optical characteristics (including beam directivity and divergence angle) of the optical elements (including optical lenses and lens supports) at high temperature, thereby causing the quality of the light spots to be reduced.

In order to solve the above problem, embodiments of the present application provide a laser, which solves the problems of deviation and power attenuation of an optical element at a high temperature of a short pulse laser by simultaneously performing temperature control on an optical sub-chip and an optical component, and simultaneously solves the problem of low power of the short pulse laser at the high temperature due to parasitic inductance by combining with a combined design of a low-inductance circuit structure.

Specifically, referring to fig. 1, in the laser provided in the embodiment of the present application, the laser includes a substrate 3, a photonic chip 1 disposed on the substrate 3, an optical component located in an emission direction of the photonic chip 1, and a temperature controller 6, where the substrate 3 and the optical component are disposed on the temperature controller 6. The optical assembly comprises a support 8 and an optical element 7 connected to the support 8, the support 8 being connected to the temperature controller 6 by means of a solder layer.

The photonic chip 1 is arranged on the substrate 3, a module formed by the photonic chip 1 and the substrate 3 is arranged on a temperature controller 6(TEC, thermal Electric Cooler), meanwhile, an optical assembly is also arranged on the temperature controller 6, and light emitted by the photonic chip 1 is emitted through the optical assembly.

As shown in fig. 2, the module formed by the photonic chip 1 and the substrate 3, and the optical component are all mounted on the temperature controller 6, so as to ensure that the optical characteristics of the optical component have small deviation in the process of high and low temperature changes, and ensure the quality of the light spot.

The optical element 7 is fixed through the support 8, and light emitted by the photonic chip 1 is emitted through the optical element 7; the support member 8 is provided on the temperature controller 6, and the support member 8 and the temperature controller 6 are connected by a welded layer.

In the prior art, the supporting piece 8 is generally fixed in a bonding mode, and when a laser works, the bonding mode is unstable in a high and low temperature environment, so that the optical assembly is subjected to position deviation on the temperature controller 6; the position deviation can cause accumulated errors on the reliability of the laser and affect the working performance of the laser.

The same material is used for the surface of the temperature controller 6, the substrate 3 and the support 8, or the thermal expansion coefficients of the surface material of the temperature controller 6, the material of the substrate 3 and the material of the support 8 are matched, so that the influence of the high-temperature thermal expansion of the materials on the quality of the light spot can be reduced.

The laser further comprises a temperature sensor arranged on the substrate, the temperature sensor is electrically connected with the temperature controller 6, and the temperature sensor is used for feeding back the temperature control condition of the temperature controller 6 in real time.

In the laser provided by the embodiment of the application, the substrate 3 is provided with the photonic chip 1, the photonic chip 1 and the substrate 3 are both arranged on the temperature controller 6, and meanwhile, the optical component is also arranged on the temperature controller 6 and is positioned in the emission direction of the photonic chip 1; install photonic chip 1, substrate 3 and optical component all on temperature controller 6, so, each device is all installed on temperature controller 6, can guarantee that each device is under same temperature, and the working property of each device can better match, and the uniformity of each device working property can be guaranteed, and can guarantee optical component's optical characteristic, such as light beam directive property and divergence angle etc. and deviation in high and low temperature change process is less, and then guarantees facula quality. Meanwhile, the support member 8 is fixed on the temperature controller 6 by welding, and the welding mode has the advantages compared with the bonding mode: 1. the welding material for welding has smaller CTE, and the welding material has smaller self-offset when the temperature changes; 2. the shear strength of the solder is higher. The stability of support piece 8 on temperature controller 6 is better, and that is to say the stability of optical element 7 is better, and through the mode of welding, the laser instrument generates heat at the during operation, reduces the offset degree of optical assembly on temperature controller 6, makes optical assembly more stable, further reduces the influence to the spot quality.

The laser further comprises a laser circuit board 2, a bonding pad is arranged on the laser circuit board 2, and the photonic chip 1 is electrically connected with the bonding pad through a bonding wire. The temperature controller 6 and the laser circuit board 2 are both arranged on the bottom plate 5.

The bottom of the laser circuit board 2 is provided with a heat sink 4, and the heat sink 4 can dissipate heat of the laser circuit board 2. In addition, the laser circuit board 2 dissipates heat through the heat sink 4, the temperature of the photonic chip 1 and the temperature of the optical element 7 are controlled through the temperature controller 6, and the heat dissipation and the temperature control are separately arranged, so that the reliability of the laser is improved.

The material of the substrate 3 can be a ceramic material with high thermal conductivity or a metal material with high thermal conductivity; the laser circuit board 2 material may be an epoxy glass cloth laminated board material, or may be a ceramic material.

The laser circuit board 2 is provided with a bonding pad, the bonding pad is conducted with the laser circuit board 2, and the photonic chip 1 is electrically connected with the bonding pad through a bonding wire so as to conduct the photonic chip 1 and the laser circuit board 2.

Specifically, the positive electrode 11 of the photonic chip 1 is electrically connected to the positive pad 21 through at least one positive bonding wire 110, and the negative electrode 12 of the photonic chip 1 is electrically connected to the negative pad 22 through at least one negative bonding wire 120.

The photonic chip 1 comprises an anode 11 and a cathode 12, the bonding pads comprise an anode bonding pad 21 and a cathode bonding pad 22, the anode 11 and the anode bonding pad 21 of the photonic chip 1 are correspondingly connected, and the cathode 12 and the cathode bonding pad 22 of the photonic chip 1 are correspondingly connected.

In one embodiment of the present application, the positive pad 21 is located on one side of the positive electrode 11 of the photonic chip 1, so when the positive electrode 11 of the photonic chip 1 and the positive pad 21 are connected by the positive bonding wire 110, the distance between the two is the shortest.

The cathode pad 22 is located in a circle with the cathode 12 of the photonic chip 1 as the center, for example, the cathode pad 22 may be located at any position in the circle, with the cathode 12 of the photonic chip 1 as the center, and the distance between the cathode 12 of the photonic chip 1 and the cathode pad 22 is in the radial direction of the circle, so that the parasitic inductance is minimum within the range of the circle with the bonding position of the photonic chip 1 as the center and the shortest bonding path as the radius.

As shown in fig. 5, the circumference forms an inductance range a, and the negative electrode pad 22 may be located at any position in the inductance range a, and fig. 5 shows three positions where the negative electrode pad 22 may be located in one inductance range a, and the negative electrode pad 22 may be located at any position in the three positions in the one inductance range a.

In another embodiment of the present application, as shown in fig. 3, the positive pad 21 is located on one side of the positive electrode 11 of the photonic chip 1, the negative pad 22 is also located on one side of the negative electrode 12 of the photonic chip 1, and the positive pad 21 and the negative pad 22 are located on the same side. At this time, the positive electrode 11 of the photonic chip 1 is connected with the positive electrode pad 21 through the positive electrode bonding wire 110, and the negative electrode 12 of the photonic chip 1 is connected with the negative electrode pad 22 through the negative electrode bonding wire 120, that is, the surface formed by the positive electrode bonding wire 110 and the surface formed by the negative electrode bonding wire 120 are respectively positioned in two different planes in an 'interchange' manner.

The arrangement can reduce the crosstalk between the anode 11 and the cathode 12, reduce the parasitic inductance, improve the power, solve the problem of power attenuation of the short pulse laser at high temperature and the problem of low power caused by the parasitic inductance, and improve the reliability of the laser.

The anode 11 of one photonic chip 1 may be electrically connected to the anode pad 21 by one or more anode bonding wires 110, and the cathode 12 of one photonic chip 1 may be electrically connected to the cathode pad 22 by one or more cathode bonding wires 120.

As shown in fig. 4, when the plurality of positive bonding wires 110 and the plurality of negative bonding wires 120 are included, the plurality of negative bonding wires 120 are parallel to each other, one ends of the plurality of positive bonding wires 110 extend towards the positive bonding pad 21, and the other ends of the plurality of positive bonding wires are diverged outwards to form a fan shape, and the area formed by the plurality of positive bonding wires 110 covers the area formed by the plurality of negative bonding wires 120, so that the signal area of the positive electrode 11 is matched with the signal area of the negative electrode 12, and signal omission caused by incomplete covering is avoided.

The positive bonding wire 110 is located on one side of the negative bonding wire 120 far away from the substrate 3, that is, the plane where the positive bonding wire 110 is located on the plane where the negative bonding wire 120 is located, the negative bonding wire 120 is close to the substrate 3, the positive bonding wire 110 is far away from the substrate 3, and the positive bonding wire 110 covers the negative bonding wire 120, so that crosstalk between the positive electrode 12 and the negative electrode 12 can be reduced, and parasitic inductance can be reduced.

A plurality of bonding wires are used for bonding, the bonding wires can be gold wires or aluminum wires, and the bonding area can be increased by the plurality of bonding wires so as to reduce the overall parasitic inductance.

In summary, in the laser provided by the embodiment of the present application, the module formed by the photonic chip 1 and the substrate 3 of the photonic chip 1 is installed on the temperature controller 6, and the optical component is installed on the temperature controller 6 at the same time, so as to ensure that the optical characteristics (beam directivity, divergence angle, etc.) of the optical component have smaller deviation in the high and low temperature change process; in order to reduce the accumulated error of the optical cement on the reliability, the optical element 7 is glued on a support 8 with matched thermal expansion coefficient, the bottom of the support 8 is metalized, and the optical element is welded on the temperature controller 6 by using low-temperature welding flux. The temperature controller 6, the substrate 3 and the support 8 are made of the same material or materials with matched thermal expansion coefficients so as to reduce the influence of high-temperature thermal expansion of the materials on the quality of the light spot. The module and the optical component formed by the photonic chip 1 and the substrate 3 are arranged on the temperature controller 6 and separated from the laser circuit board 2, the bonding position of the photonic chip 1 is taken as the circle center, the shortest bonding path is taken as the radius, the bonding range of the laser circuit board 2 is enabled to be in the circular ring, and when the laser circuit board is in the circular ring range, the parasitic inductance is minimum. In another embodiment, the positive bonding wire 110 is covered on the negative bonding wire 120, so that the crosstalk between the positive electrode 12 and the negative electrode 12 is reduced, and the parasitic inductance is reduced.

The photonic chip 1 and the substrate 3 of the laser form a module which is separated from the laser circuit board 2, namely, the photonic chip 1 and the laser circuit board 2 are two parts, and the photonic chip 1 is in wire bonding with the laser circuit board 2 through a bonding pad on the laser circuit board 2 to form a low inductance loop. The temperature of the module of the photonic chip 1 and the temperature of the optical component are controlled by the temperature controller 6, so that the temperature of each device on the temperature controller 6 is ensured to be at the same temperature, the temperature consistency is ensured, the laser circuit board 2 independently dissipates heat through the heat sink 4, the structure of the laser circuit board 2 can be in any shape, and the engineering design of the laser circuit board 2 is facilitated; the temperature of the photonic chip 1 is controlled independently, the heat dissipation of the laser circuit board 2 is processed correspondingly, the temperature of the photonic chip 1 module and the temperature of the laser circuit board 2 can be controlled and dissipated respectively, the reliability of the product is greatly improved, good heat dissipation is achieved, and parasitic inductance is reduced. With the increasing market demand for short-pulse high-power semiconductor lasers, the laser provided by the embodiment of the application can simultaneously meet the requirements of low parasitic inductance and independent temperature control.

The above description is only an example of the present application and is not intended to limit the scope of the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A laser, characterized in that the laser comprises: the optical component comprises a support and an optical element connected with the support, and the support is connected with the temperature controller through a welding layer.

2. The laser of claim 1, wherein the coefficients of thermal expansion of the surface material of the temperature controller, the material of the substrate, and the material of the support are matched.

3. The laser of claim 2, further comprising a temperature sensor disposed on the substrate, the temperature sensor being electrically connected to the temperature controller.

4. The laser of claim 1, further comprising a laser circuit board having a pad disposed thereon, wherein the photonic chip and the pad are electrically connected by a bonding wire.

5. The laser of claim 4, wherein a heat sink is provided on a bottom of the laser circuit board.

6. The laser of claim 4, wherein the positive pole of the photonic chip is electrically connected to the positive pad by at least one positive bond wire and the negative pole of the photonic chip is electrically connected to the negative pad by at least one negative bond wire.

7. The laser of claim 6, wherein the negative bond pad is located within a circumference centered on a negative pole of the photonic chip.

8. The laser of claim 6, wherein the positive and negative bond wires are located in two different planes.

9. The laser device according to claim 8, wherein the plurality of positive bonding wires and the plurality of negative bonding wires are parallel to each other, one end of each of the plurality of positive bonding wires extends in a direction of the positive bonding pad, and the other end of each of the plurality of positive bonding wires diverges outward in a fan shape, and an area formed by the plurality of positive bonding wires covers an area formed by the plurality of negative bonding wires.

10. A laser as claimed in claim 8 or 9, wherein the positive bond wire is located on a side of the negative bond wire remote from the substrate.