阅读说明：本技术 激光发射组件 (Laser emitting assembly ) 是由 汤小虎 庄睿 汤卓恒 于 2018-08-15 设计创作，主要内容包括：本申请提供了激光发射组件,所述激光发射组件包括底座、位于所述底座表面的基体和位于所述基体正面的激光芯片,所述基体包括与正面相对的背面；其中：所述基体正面还设置有第一导电片、第二导电片、第一微带线和第二微带线；第一微带线的一端电连接所述激光芯片的第一电极、另一端通过第一打线电连接第一导电片；第二微带线的一端电连接所述激光芯片的第二电极、另一端通过第二打线电连接第二导电片；所述激光发射组件还包括回流信号传输结构,所述回流信号传输结构设置于所述基体的顶面和/或背面。该激光发射组件在发射高速信号时,具有良好性能。(The application provides a laser emission assembly, which comprises a base, a base body and a laser chip, wherein the base body is positioned on the surface of the base, the laser chip is positioned on the front surface of the base body, and the base body comprises a back surface opposite to the front surface; wherein: the front surface of the substrate is also provided with a first conducting strip, a second conducting strip, a first microstrip line and a second microstrip line; one end of the first microstrip line is electrically connected with the first electrode of the laser chip, and the other end of the first microstrip line is electrically connected with the first conducting strip through the first wire bonding; one end of the second microstrip line is electrically connected with the second electrode of the laser chip, and the other end of the second microstrip line is electrically connected with the second conducting strip through a second routing; the laser emission assembly further comprises a backflow signal transmission structure, and the backflow signal transmission structure is arranged on the top surface and/or the back surface of the base body. The laser emitting assembly has good performance when emitting high-speed signals.)

1. A laser emission component comprises a base, a substrate and a laser chip, wherein the substrate is positioned on the surface of the base, the laser chip is positioned on the front surface of the substrate, and the substrate comprises a back surface opposite to the front surface; the method is characterized in that:

the front surface of the substrate is also provided with a first conducting strip, a second conducting strip, a first microstrip line and a second microstrip line;

one end of the first microstrip line is electrically connected with the first electrode of the laser chip, and the other end of the first microstrip line is electrically connected with the first conducting strip through the first wire bonding; one end of the second microstrip line is electrically connected with the second electrode of the laser chip, and the other end of the second microstrip line is electrically connected with the second conducting strip through a second routing;

the laser emission assembly further comprises a backflow signal transmission structure, and the backflow signal transmission structure is arranged on the top surface and/or the back surface of the base body.

2. The laser emitting assembly of claim 1,

the return signal transmission structure includes: a first return signal transmission structure and a second return signal transmission structure;

the first backflow signal transmission structure is located on the back face of the base body and opposite to the first routing, and the second backflow signal transmission structure is located on the back face of the base body and opposite to the second routing.

3. The laser emitting assembly of claim 1,

the substrate includes: the device comprises a first base body, a second base body and a third base body which are separated from each other and arranged in sequence, wherein the first base body, the second base body and the third base body are all made of conductive materials;

the first conducting strip is arranged on the front surface of the first substrate, the second conducting strip is arranged on the front surface of the third substrate, and the first microstrip line, the second microstrip line and the laser chip are arranged on the front surface of the second substrate;

the return signal transmission structure is arranged between the top surfaces and/or the back surfaces of the first base body and the second base body and between the top surfaces and/or the back surfaces of the second base body and the third base body.

4. The laser emitting assembly of claim 3,

the return signal transmission structure includes: a first return signal transmission structure and a second return signal transmission structure;

the first backflow signal transmission structure is located between the back faces of the first base body and the second base body and is opposite to the first routing, and the second backflow signal transmission structure is located between the back faces of the second base body and the third base body and is opposite to the second routing.

5. The laser emitting assembly of claim 4, further comprising:

and the heat dissipation structure is arranged between the second base body and the base.

6. The laser emitting assembly of claim 4, wherein:

the first and second backflow transmission structures are both routing wires.

7. The laser emitting assembly of claim 4, wherein:

the first, second and third substrates are all equal in thickness, wherein the thickness is the distance between the front and back surfaces.

8. The laser emitting assembly of claim 7, wherein:

the thickness ranges from 0.08mm to 0.32 mm.

9. The laser emitting assembly of claim 1, further comprising:

and the optical detector is arranged between the base and the laser chip and is used for receiving laser emitted by the laser chip.

10. The laser emitting assembly of claim 1, wherein:

the thickness of the base body close to the base part is larger than that of the base body far away from the base part, wherein the thickness is the distance between the front surface and the back surface of the base body.

Technical Field

The application relates to the technical field of optical communication, in particular to a refrigeration type laser emission assembly.

Background

With the progress of the times and the development of technologies, optical communications are developed vigorously. The high-speed optical transceiver module is a key component for completing the photoelectric conversion of these high-speed optical fiber systems, and the core component of these components is a Laser emission component with a standard optical interface, and the Laser emission component is a metal kit for installing a Laser Device (LD) in the standard optical interface with high precision.

Therefore, how to design a laser emitting assembly for optical communication becomes a problem to be solved.

Content of application

An object of the present application is to provide a laser emitting assembly of a refrigeration type.

In order to achieve one of the above-mentioned objectives, an embodiment of the present application provides a laser emitting assembly, which includes a base, a substrate located on a surface of the base, and a laser chip located on a front surface of the substrate, wherein the substrate includes a back surface opposite to the front surface; wherein: the front surface of the substrate is also provided with a first conducting strip, a second conducting strip, a first microstrip line and a second microstrip line; one end of the first microstrip line is electrically connected with the first electrode of the laser chip, and the other end of the first microstrip line is electrically connected with the first conducting strip through the first wire bonding; one end of the second microstrip line is electrically connected with the second electrode of the laser chip, and the other end of the second microstrip line is electrically connected with the second conducting strip through a second routing; the laser emission assembly further comprises a backflow signal transmission structure, and the backflow signal transmission structure is arranged on the top surface and/or the back surface of the base body.

As a further improvement of an embodiment of the present application, the return signal transmission structure includes: a first return signal transmission structure and a second return signal transmission structure; the first backflow signal transmission structure is located on the back face of the base body and opposite to the first routing, and the second backflow signal transmission structure is located on the back face of the base body and opposite to the second routing.

As a further improvement of an embodiment of the present application, the substrate includes: the device comprises a first base body, a second base body and a third base body which are separated from each other and arranged in sequence, wherein the first base body, the second base body and the third base body are all made of conductive materials; the first conducting strip is arranged on the front surface of the first substrate, the second conducting strip is arranged on the front surface of the third substrate, and the first microstrip line, the second microstrip line and the laser chip are arranged on the front surface of the second substrate; the return signal transmission structure is arranged between the top surfaces and/or the back surfaces of the first base body and the second base body and between the top surfaces and/or the back surfaces of the second base body and the third base body.

As a further improvement of an embodiment of the present application, the return signal transmission structure includes: a first return signal transmission structure and a second return signal transmission structure; the first backflow signal transmission structure is located between the back faces of the first base body and the second base body and is opposite to the first routing, and the second backflow signal transmission structure is located between the back faces of the second base body and the third base body and is opposite to the second routing.

As a further improvement of an embodiment of the present application, the present invention further includes: and the heat dissipation structure is arranged between the second base body and the base.

As a further improvement of an embodiment of the present application, the first and second reflow transmission structures are both wire bonding.

As a further improvement of an embodiment of the present application, the first, second and third substrates are all equal in thickness, wherein the thickness is the distance between the front and back surfaces.

As a further improvement of an embodiment of the present application, the thickness ranges from 0.08mm to 0.32 mm.

As a further improvement of an embodiment of the present application, the present invention further includes:

and the optical detector is arranged between the base and the laser chip and is used for receiving laser emitted by the laser chip.

As a further improvement of an embodiment of the present application, a thickness of the base body near the base portion is larger than a thickness of the base body far from the base portion, wherein the thickness is a distance between the front surface and the back surface of the base body.

Compared with the prior art, the technical effect of this application lies in: the embodiment of the application provides a laser emission assembly, which comprises a base, a base body and a laser chip, wherein the base body is positioned on the surface of the base, the laser chip is positioned on the front surface of the base body, and the base body comprises a back surface opposite to the front surface; wherein: the front surface of the substrate is also provided with a first conducting strip, a second conducting strip, a first microstrip line and a second microstrip line; one end of the first microstrip line is electrically connected with the first electrode of the laser chip, and the other end of the first microstrip line is electrically connected with the first conducting strip through the first wire bonding; one end of the second microstrip line is electrically connected with the second electrode of the laser chip, and the other end of the second microstrip line is electrically connected with the second conducting strip through a second routing; the laser emission assembly further comprises a backflow signal transmission structure, and the backflow signal transmission structure is arranged on the top surface and/or the back surface of the base body. The laser emitting assembly has good performance when emitting high-speed signals.

Drawings

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

fig. 2 is a second structural schematic diagram of a laser emitting assembly in an embodiment of the present application;

FIG. 3 is a schematic view of a third structure of a laser emitting assembly in an embodiment of the present application;

fig. 4 is a fourth structural schematic diagram of a laser transmitter assembly in an embodiment of the present application;

fig. 5 is a schematic structural diagram of a heat dissipation device in an embodiment of the present application;

fig. 6 is a fifth structural schematic diagram of a laser transmitter assembly in an embodiment of the present application;

FIGS. 7a and 7b are schematic diagrams of the performance of a prior art laser emitting assembly;

FIGS. 8a, 8b and 8c are schematic diagrams of a first performance of a laser emitting assembly in an embodiment of the present application;

fig. 9a, 9b and 9c are second performance diagrams of the laser transmitter assembly in the embodiment of the present application.

Detailed Description

The present application will be described in detail below with reference to embodiments shown in the drawings. These embodiments are not intended to limit the present application, and structural, methodological, or functional changes made by those skilled in the art according to these embodiments are included in the scope of the present application.

The first embodiment of the present application provides a laser emission assembly, as shown in fig. 1 to 4, the laser emission assembly includes a base 1, a substrate located on a surface of the base 1, and a laser chip 31 located on a front surface of the substrate, where the substrate includes a back surface opposite to the front surface; here, the base 1 may be cylindrical, for example, in fig. 1-4, the base 1 is substantially cylindrical, and the surface of the base 1 is circular. In the substrate, one side surface where the laser chip 31 is located is a front surface, and the other side surface opposite to the front surface is a back surface.

The front surface of the substrate is also provided with a first conducting strip 21, a second conducting strip 41, a first microstrip line 32 and a second microstrip line 33;

one end of the first microstrip line 32 is electrically connected to the first electrode of the laser chip 31, and the other end is electrically connected to the first conductive plate 21 through the first routing 22; one end of the second microstrip line 33 is electrically connected to the second electrode of the laser chip 31, and the other end is electrically connected to the second conductive plate 41 through the second routing wire 42;

the laser emission assembly further comprises a backflow signal transmission structure 5, and the backflow signal transmission structure 5 is arranged on the top surface and/or the back surface of the base body. Here, the arrangement of the return signal transmitting structure 5 may be various, for example, (1) arranged on the back surface of the base; (2) the top surface of the substrate is provided; (3) the top surface and the back surface of the substrate are both provided. In fig. 1 and 2, both the top and back surfaces of the substrate are provided; whereas in fig. 3 and 4, it is provided only on the back side of the substrate.

The thickness of the base body at the part close to the base seat 1 is larger than that of the base body far away from the base seat 1, wherein the thickness is the distance between the front surface and the back surface of the base body. That is the thickness that the part of base member is close to base 1 is greater than the thickness of keeping away from base 1 part to enlarged the area of contact of base member and base, it can be understood that, when luminous, laser chip 31 can produce the heat, and this heat has the part to conduct on the base member, also has the part to conduct on the base, and base member and base can both give off the heat promptly, consequently, area of contact has enlarged, can be convenient for more on the heat conduction base, the thermal giving off of being convenient for more.

In practical use, electrical signals need to be input to the first and second conductive sheets respectively to provide current for the laser chip 31, so as to drive the laser chip 31 to emit laser; the current will carry data and the current value will change rapidly, it is a high speed signal, the laser chip 31 will emit laser carrying signal, this current is different from the bias current, this current can be understood as the sum of the bias current and the modulation current.

In the prior art, the reflow signal transmission structure and the signal lines (i.e. the first bonding wires 22 and the second bonding wires 42) are arranged substantially in parallel, and the high-speed signal is transmitted across the board portion in a waveguide mode; the disadvantage of this routing method is that, due to the microstrip transmission line structure, the transmission mode of the signal is converted from the microstrip to the waveguide structure, resulting in the loss of mode field conversion. For example, in the simulation results of fig. 7a and 7b, in a system with a characteristic impedance of 25Ohm, the impedance of the bonding wire across the board is 26.71Ohm, which is significantly higher, and the passivity performance such as insertion loss and return loss can be greatly improved.

In the long-term practice of the inventor, it is found that if the return signal transmission structure of the high-speed signal line is in the vicinity of the high-speed signal line, the closer the distance is and/or the frequency is higher, the less energy is lost by the transmission line, and therefore, the return path of the high-speed signal can be made as close as possible and the covered area is larger.

In the laser emission assembly of the present application, the return signal transmission structure (i.e., GND plane) responsible for signal return is designed to be opposite to or on the top surface (i.e., on the top surface and/or the back surface of the substrate) of the high-speed signal routing, so as to provide a reference for the high-speed routing of the cross-board portion, as shown in fig. 8a, 8b and 8c, in the laser emission assembly of the present application, when the impedance of the cross-board routing is optimized to 25.13Ohm, and the insertion loss is above 20GHz, the improvement is obvious compared with the routing manner in the prior art, and the return loss is obviously improved in the frequency band above 5 GHz.

As shown in fig. 2 and 4, the backflow signal transmission structure includes: a first return signal transmission structure 51 and a second return signal transmission structure 52; the first reflow signal transmission structure 51 is located on the back surface of the substrate and is opposite to the first wire 22, and the second reflow signal transmission structure 52 is located on the back surface of the substrate and is opposite to the second wire 42.

As shown in fig. 1 to 4, the laser emitting assembly further includes: and the light detector 14 is arranged between the base 1 and the laser chip 31, and the light detector 14 is used for receiving the laser emitted by the laser chip 31.

The optical detector 14 is arranged between the base 1 and the laser chip 31 to receive laser emitted by the laser chip 31; here, the laser chip 31 emits two laser beams perpendicular to the surface of the base 1, wherein one laser beam is emitted in a direction away from the surface of the base 1, and the other laser beam is emitted in a direction toward the surface of the base 1, so as to be emitted to the optical detector 14, so that the optical detector 14 can detect the power of the laser beam, and further, the optical power of the laser chip 31 is monitored.

The substrate includes: the device comprises a first base body 2, a second base body 3 and a third base body 4 which are separated from each other and arranged in sequence, wherein the first base body, the second base body and the third base body are all made of conductive materials.

The first conducting strip 21 is arranged on the front surface of the first substrate 2, the second conducting strip 41 is arranged on the front surface of the third substrate 4, and the first microstrip line 32, the second microstrip line 33 and the laser chip 31 are arranged on the front surface of the second substrate 3. An insulating layer is arranged between the first conductive sheet 21 and the second conductive sheet 41 and the first substrate 2.

The return signal transmission structures 5 are arranged between the top faces and/or the back faces of the first and second substrates and between the top faces and/or the back faces of the second and third substrates.

The first reflow signal transmission structure 51 is located between the back surfaces of the first and second substrates and opposite to the first wire 22, and the second reflow signal transmission structure 52 is located between the back surfaces of the second and third substrates and opposite to the second wire 42.

In the laser emitting assembly of the present application, a routing is provided between the back surface of the first base 2 and the back surface of the second base 3, and a routing is also provided between the back surface of the second base 3 and the back surface of the third base 4.

The first, second and third substrates are all equal in thickness, wherein the thickness is the distance between the front and back surfaces. Here, the first substrate 2, the second substrate 3 and the third substrate 4 can be thinned, and according to the long-term practice of the inventor, it is found that the closer the distance between the first reflow signal transmission structure 51 and the first wire 22 is, and the closer the distance between the second reflow signal transmission structure 52 and the second wire 42 is, the better the high-speed effect is, for example, fig. 9a, 9b and 9c show three results that the distances between the front surface and the back surface (i.e. the thicknesses of the first, the second and the third substrate) are 0.3mm, 0.2mm and 0.1mm, respectively, and it can be seen that the closer the distance between the reflow signal transmission structure and the signal line is, the more the high-speed performance of the structure can be improved. This thickness range may be from 0.08mm to 0.32mm and it has been found by long-term practice of the inventors that the first, second and third substrates have better strength and better high frequency performance when the thickness is in this range.

As shown in fig. 6, the laser emission assembly may further include a cap 6, the cap 6 being capable of encapsulating the base 1 and having a receiving cavity for receiving electronic components (i.e., the photodetector 14, the laser chip 31, the first substrate 2, the second substrate 3, the third substrate 4, etc.); a lens window 61 for allowing the laser to pass through is further provided in the cap 6, and the laser emitted from the laser chip 31 and directed away from the surface of the base 1 can be emitted through the lens window 61.

The first and second backflow transmission structures are both routing wires.

The laser emitting assembly further includes: and the heat dissipation structure 13 is arranged between the second base body 3 and the base 1, wherein the heat dissipation structure 13 is arranged between the second base body 3 and the base 1. Here, as shown in fig. 1-4, the laser chip 31 is disposed on the second substrate 3, and the second substrate 3 is connected to the heat sink 13, so that the heat generated by the laser chip 31 is conducted to the heat sink 13 through the second substrate 3 and then dissipated by the heat sink 13; the heat generated by the light detector 14 is directly conducted to the heat sink 13 and dissipated by the heat sink 13.

The heat sink 13 is a semiconductor refrigerator.

Optionally, a heat dissipation hole 131 is disposed in the heat dissipation device 13. Here, the heat dissipation holes 131 may increase the heat dissipation speed of the heat dissipation device 13. As shown in fig. 5, the heat dissipation holes 131 may include a first heat dissipation hole 1311 penetrating through the heat dissipation device 13, and a plurality of second heat dissipation holes 1312 penetrating through the heat dissipation device 13 and perpendicular to the first heat dissipation hole 1311. The central lines of the first heat dissipation hole and the second heat dissipation hole are parallel to the surface of the base 1, namely the heat dissipation device 13 horizontally penetrates through the base 1, so that the contact surface of the heat dissipation device 13 and the base 1, the contact surface of the heat dissipation device 13 and the second base body 3, and the contact surface of the heat dissipation device 13 and the optical detector 14 are flat planes without pits, and heat can be conducted between the components conveniently.

The laser emitting component comprises a first pin 11 and a second pin 12 which penetrate through the base 1; the first pins 11 are electrically connected to the first conductive plate 21, and the second pins 12 are electrically connected to the second conductive plate 41.

Alternatively, the first pins 11 are soldered to the first conductive sheet 21 and the second pins 12 are soldered to the second conductive sheet 41. Here, the base 1 may be made of a metal material, and since a part of heat of the heat sink 13 may be conducted to the base 1, the metal base 1 can dissipate heat better; it can be understood that the first and second pins need to be connected with the metal base 1 in an insulating manner, for example, in fig. 1 to 4, the first and second pins are wrapped by an insulator 15, so as to achieve the insulation between the first and second pins and the base 1; and as shown in fig. 1-4, other pins penetrate through the base 1, and the pins and the base 1 need insulation connection. Alternatively, the insulator 15 may be an insulating material such as glass.

Here, in laser communication, the length of the wire bonding between the laser chip 31 and the pin is critical to the performance of a high-speed device, because the wire bonding can be equivalent to an element having both resistance and inductance characteristics in terms of high-frequency characteristics, and the longer the length of the wire bonding, the larger the parasitic inductance, and the more uncontrollable factors of the wire bonding length and radian in production, it is difficult to accurately estimate the actual equivalent resistance inductance effect of the wire bonding during device packaging, the uncontrollable performance of the device is caused, and meanwhile, the introduction of the resistance and the inductance can affect the high-frequency characteristics of the device, which is not beneficial to high-frequency transmission. Therefore, in high-speed device packaging, it is desirable to make the length of wire bonding as short as possible, make the height of wire loop as low as possible, and make the number of wire bonding as large as possible, in order to reduce parasitic parameters and improve the performance of the device. In the laser emitting assembly, the first pin and the second pin are respectively welded to the first conducting strip and the second conducting strip, so that the routing length of the laser chip 31 and the tube seat 1 is effectively reduced.

The routing is at least two gold wires connected in parallel.

The embodiment of the invention also provides a laser module which comprises the laser emitting assembly.

The second embodiment of the present invention provides an assembling method for the laser emitting assembly, which includes the following steps:

step 1: providing a base 1, a substrate and a laser chip 31; mounting the laser chip 31 on the front surface of the substrate, and mounting the substrate on the surface of the base 1;

step 2: a first conductive sheet 21, a second conductive sheet 41, a first microstrip line 32 and a second microstrip line 33 are arranged on the front surface of the substrate; one end of a first microstrip line 32 is electrically connected with the first electrode of the laser chip 31, and the other end is electrically connected with the first conducting strip 21 through a first routing 22; one end of the second microstrip line 33 is electrically connected to the second electrode of the laser chip 31, and the other end is electrically connected to the second conductive sheet 41 through the second routing 42;

and step 3: a return signal transmission structure 5 is mounted on the top and/or back of the substrate.

It should be understood that although the present description refers to embodiments, not every embodiment contains only a single technical solution, and such description is for clarity only, and those skilled in the art should make the description as a whole, and the technical solutions in the embodiments can also be combined appropriately to form other embodiments understood by those skilled in the art.

The above list of details is only for the concrete description of the feasible embodiments of the present application, they are not intended to limit the scope of the present application, and all equivalent embodiments or modifications that do not depart from the technical spirit of the present application are intended to be included within the scope of the present application.