CN111913257A

CN111913257A - Optical module and optical module having the same

Info

Publication number: CN111913257A
Application number: CN201910383928.5A
Authority: CN
Inventors: 汪振中; 贾秀红
Original assignee: Innolight Technology Suzhou Ltd
Current assignee: Innolight Technology Suzhou Ltd
Priority date: 2019-05-09
Filing date: 2019-05-09
Publication date: 2020-11-10

Abstract

The application discloses optical assembly and have its optical module, optical assembly includes signal line, ground plane and bonding wire, and the signal line includes first signal line, the second signal line of interval distribution, and the bonding wire includes first bonding wire and at least one second bonding wire of adjacent setting, and first bonding wire connects first signal line and second signal line, and the second bonding wire connects the ground plane, just at least partial unsettled cover of second bonding wire is in the air above the signal line. The second bonding wire of this application connects the horizon and forms electromagnetic shield, and the second bonding wire is regional through the signal line that sets up first bonding wire, and electromagnetic shield effect can radiate well to first bonding wire region, can reduce the perception of first bonding wire, reduces the impedance of first bonding wire, is favorable to the high-efficient transmission of signal in the signal line, and can reduce the loss greatly, improves transmission bandwidth, accords with high frequency design requirement.

Description

Optical module and optical module having the same

Technical Field

The application relates to the technical field of optical communication element manufacturing, in particular to an optical assembly and an optical module with the same.

Background

In the prior art, in two links to be connected, conduction and signal transmission are usually realized through bonding wires, but the bonding wires themselves have strong inductance, and mutual inductance also exists between adjacent bonding wires, so that the impedance of the bonding wires is high, and abrupt points of impedance exist at the bonding wires of the whole link, so that the loss is large, and the development of an optical module with higher speed is not facilitated.

Disclosure of Invention

The application discloses optical assembly and have its optical module, optical assembly includes signal line, horizon and bonding wire, the signal line includes first signal line, the second signal line of interval distribution, the bonding wire includes first bonding wire and an at least second bonding wire of neighbouring setting, first bonding wire is connected first signal line reaches the second signal line, the second bonding wire is connected the horizon, just the second bonding wire at least part is unsettled cover in the signal line top.

In one embodiment, at least a portion of the second bonding wires is suspended over the first bonding wires.

In an embodiment, the ground plane includes a left ground plane and a right ground plane located at two sides of the signal line, and the second bonding wire connects the left ground plane and the right ground plane.

In an embodiment, the left ground plane includes a first left ground plane and a second left ground plane that are distributed at intervals, the right ground plane includes a first right ground plane and a second right ground plane that are distributed at intervals, the bonding wire further includes a third bonding wire and a fourth bonding wire, the third bonding wire connects the first left ground plane and the second left ground plane, and the fourth bonding wire connects the first right ground plane and the second right ground plane.

In an embodiment, one end of the second bonding wire is connected to one of the first left ground plane and the second left ground plane, and the other end of the second bonding wire is connected to one of the first right ground plane and the second right ground plane.

In an embodiment, the bonding wires include four groups of second bonding wires, and the four groups of second bonding wires are respectively connected to the first left ground plane and the first right ground plane, the first left ground plane and the second right ground plane, the second left ground plane and the first right ground plane, and the second left ground plane and the second right ground plane.

In an embodiment, the first bonding wire comprises two first sub-bonding wires having a first gap, the third bonding wire comprises two third sub-bonding wires having a third gap, and the first gap is larger than the third gap.

In one embodiment, the first bonding wire comprises two first sub bonding wires distributed at intervals, and the contact point of the first sub bonding wire and the signal wire is located within 100 micrometers inward of the edge of the signal wire.

In one embodiment, the optical module includes a first component and a second component that are distributed at intervals, the first signal line is located in the first component, the second signal line is located in the second component, and the first component and the second component may be optical transceiver devices or circuit boards.

The application discloses a light module, which comprises the optical assembly according to any one of the technical schemes.

Compared with the prior art, the second bonding wire of the technical scheme of the application is connected with the ground plane to form electromagnetic shielding, and the second bonding wire passes through the signal wire area provided with the first bonding wire, so that the electromagnetic shielding effect can be well radiated to the first bonding wire area, the sensitivity of the first bonding wire can be reduced, the impedance of the first bonding wire is reduced, the efficient transmission of signals in the signal wire is facilitated, the loss can be greatly reduced, the transmission bandwidth is improved, and the high-frequency design requirement is met.

Drawings

FIG. 1 is a perspective view of an optical assembly of the present application;

FIG. 2 is a top view of an optical assembly of the present application;

FIG. 3 is an enlarged view of a portion of FIG. 2;

FIG. 4 is a perspective view of a prior art optical assembly;

FIG. 5 is a top view of a prior art optical assembly;

FIG. 6 is an enlarged view of a portion of FIG. 5;

FIG. 7 is a graph of the effect of impedance simulation at a first bond wire in the prior art and the present application;

FIG. 8 is a graph of the effect of return loss simulation in the prior art and the present application;

FIG. 9 is a graph of insertion loss simulation effect in the prior art and the present application;

fig. 10 is a prior art current profile at a first bond wire;

fig. 11 is a current distribution diagram at a first bond wire in the present application.

Detailed Description

The present application will now be described in detail with reference to specific embodiments thereof as illustrated in the accompanying 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.

In the various illustrations of the present application, certain dimensions of structures or portions may be exaggerated relative to other structures or portions for ease of illustration and, thus, are provided to illustrate only the basic structure of the subject matter of the present application.

Also, terms used herein such as "upper," "above," "lower," "below," and the like, denote relative spatial positions of one element or feature with respect to another element or feature as illustrated in the figures for ease of description. The spatially relative positional terms may be intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as "below" or "beneath" other elements or features would then be oriented "above" the other elements or features. Thus, the exemplary term "below" can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

Referring to fig. 1 to 3, an embodiment of the present application provides an optical assembly 100.

The optical component 100 includes a signal wire 10, a ground plane 20, and a bond wire 30.

The signal line 10 includes a first signal line 11 and a second signal line 12 that are spaced apart from each other.

Here, the signal line 10 is used for transmitting signals, and the signal line 10 is, for example, a Radio Frequency (RF) signal line, but not limited thereto.

In addition, "spaced apart" means that the first signal line 11 and the second signal line 12 are disconnected from each other.

The bonding wires 30 include a first bonding wire 31 and at least one second bonding wire 32 disposed adjacently.

The first bonding wire 31 connects the first signal line 11 and the second signal line 12.

The second bonding wire 32 is connected to the ground plane 20, and at least a portion of the second bonding wire 32 is suspended above the signal line 10.

Here, the bonding wire 30 may be, for example, a gold wire, the bonding wire 30 may be fixed to the signal line 10 or the ground plane 20 by soldering, the bonding wire 30 is used to implement signal transmission between two links that need to be connected, and for example, the first bonding wire 31 may implement signal transmission between the first signal line 11 and the second signal line 12.

In addition, "adjacent to each other" means that the first bonding wire 31 and the at least one second bonding wire 32 are adjacently disposed, the first bonding wire 31 connects the first signal line 11 and the second signal line 12, and the second bonding wire 32 surrounds or is disposed in the distribution area of the first bonding wire 31; the phrase "the second bonding wire 32 at least partially covers the signal line 10 in the air" means that the extending path of the second bonding wire 32 passes through the signal line 10 region, and the second bonding wire 32 and the signal line 10 are not in contact with each other.

The second bonding wire 32 of the present embodiment is connected to the ground plane 20 to form an electromagnetic shielding, and the second bonding wire 32 passes through the signal wire 10 region where the first bonding wire 31 is disposed, so that the electromagnetic shielding effect can be well radiated to the first bonding wire 31 region, the inductance of the first bonding wire 31 can be reduced, the impedance of the first bonding wire 31 can be reduced, the efficient transmission of signals in the signal wire 10 can be facilitated, the loss can be greatly reduced, the transmission bandwidth can be improved, and the high-frequency design requirement can be met.

In the present embodiment, at least a portion of the second bonding wire 32 is suspended above the first bonding wire 31.

That is, at least a portion of the second bonding wires 32 is arranged to cross the first bonding wires 31, so that the impedance of the first bonding wires 31 can be further reduced.

In this embodiment, the optical module 100 includes a first member 101 and a second member 102 spaced apart from each other, the first signal line 11 is located in the first member 101, and the second signal line 12 is located in the second member 102.

Here, the first component 101 and the second component 102 may be optical transceivers or circuit boards, but not limited thereto, and the first component 101 and the second component 102 may be package structures bonded by other bonding wires.

For example, the first component 101 is a Transmitter Optical Subassembly (TOSA) 101, the second component 102 is a Printed Circuit Board (PCB) 102, and when the first bonding wire 31 is used to interconnect the light emitting device 101 and the Printed Circuit Board 102, in order to obtain a higher bandwidth and meet the high frequency design requirement, it is necessary to ensure the impedance continuity among the first bonding wire 31, the light emitting device 101 and the Printed Circuit Board 102 as much as possible, and the second bonding wire 32 provided in the present embodiment can effectively reduce the influence of the inductance of the first bonding wire 31 on the impedance continuity, thereby increasing the transmission bandwidth to meet the high frequency design requirement.

Referring to fig. 2 and 3, an optical assembly 100 according to an embodiment of the present invention is shown.

The ground plane 20 includes a left ground plane 21 and a right ground plane 22 located at two sides of the signal line 10, and the second bonding wire 32 connects the left ground plane 21 and the right ground plane 22.

The left ground plane 21 includes a first left ground plane 211 and a second left ground plane 212 that are spaced apart from each other, and the right ground plane 22 includes a first right ground plane 221 and a second right ground plane 222 that are spaced apart from each other.

Here, the left ground plane 21, the signal line 10, and the right ground plane 22 are sequentially arranged in parallel, the first left ground plane 211, the first signal line 11, and the first right ground plane 221 are located on the first member 101, the second left ground plane 212, the second signal line 12, and the second right ground plane 222 are located on the second member 102, and the first member 101 and the second member 102 are spaced apart from each other.

The bonding wires 30 also include a third bonding wire 33 and a fourth bonding wire 34.

A third bondline 33 connects the first left ground plane 211 and the second left ground plane 212 and a fourth bondline 34 connects the first right ground plane 221 and the second right ground plane 222.

That is, the first part 101 and the second part 102 are interconnected by the first bonding wire 31, the third bonding wire 33, and the fourth bonding wire 34.

One end of the second bonding wire 32 is connected to one of the first left ground plane 211 and the second left ground plane 212, and the other end of the second bonding wire 32 is connected to one of the first right ground plane 221 and the second right ground plane 222, so that the extending path of the second bonding wire 32 can be ensured to pass through the signal line 10 region.

Specifically, the bonding wires 30 include four sets of second bonding wires 32, and the four sets of second bonding wires 32 are respectively connected to the first left ground plane 211 and the first right ground plane 221, the first left ground plane 211 and the second right ground plane 222, the second left ground plane 212 and the first right ground plane 221, the second left ground plane 212 and the second right ground plane 222.

Here, the first group of second bonding wires 32a connects the first left ground plane 211 and the first right ground plane 221, the second group of second bonding wires 32b connects the first left ground plane 211 and the second right ground plane 222, the third group of second bonding wires 32c connects the second left ground plane 212 and the first right ground plane 221, and the fourth group of second bonding wires 32d connects the second left ground plane 212 and the second right ground plane 222.

That is, the extending directions of the first and fourth groups of

second bonding wires

32a and 32d are parallel to the arrangement direction of the left ground plane 21, the signal line 10 and the right ground plane 22, the first group of second bonding wires 32a is located in the first component 101, and the fourth group of second bonding wires 32d is located in the second component 102; the second and third groups of second and

third bonding wires

32b, 32c are crossing bonding wires, and the second and third groups of second and

third bonding wires

32b, 32c are connected to the first and

second components

101, 102.

It can be seen that in the present specific example, the plurality of sets of second bonding wires 32 arranged in parallel and crosswise form an electromagnetic shield that covers the first bonding wire 31 on all sides, so that the inductance of the first bonding wire 31 can be reduced more effectively, and the impedance at the first bonding wire 31 is more continuous.

In this particular example, the first bondwire 31 includes two first sub-bondwires 31a having a first gap, and the third bondwire 33 includes two third sub-bondwires 33a having a third gap, the first gap being greater than the third gap.

That is, the gap between the two first sub-bonding wires 31a is large, so that the mutual inductance between the two first sub-bonding wires 31a can be reduced, the impedance can be reduced, and the impedance continuity can be further increased.

In other examples, the first bonding wire 31 includes two spaced first sub-bonding wires 31a, and a contact point of the first sub-bonding wire 31a with the signal line 10 is located within 100 micrometers inward of an edge of the signal line 10.

Here, the two first sub-bonding wires 31a are arranged in parallel, the signal line 10 is a strip microstrip line structure, and both the two first sub-bonding wires 31a are arranged in parallel to the edge of the signal line 10.

That is, the two first sub-bonding wires 31a are disposed close to the edge of the signal line 10, so that a gap between the two first sub-bonding wires 31a is large enough to reduce mutual inductance between the two first sub-bonding wires 31a, reduce impedance, and further increase impedance continuity.

In this specific example, the second bonding wire 32 and the fourth bonding wire 34 each include two sub-bonding wires, but not limited thereto.

It is understood that the number and the arrangement position of the second bonding wires 32 may be determined according to actual situations in other examples.

Next, the optical module 100 of the present application and the optical module 100' of the prior art will be described in comparison.

Fig. 4 to 6 are schematic diagrams of an optical assembly 100' in the prior art, and for convenience of description, similar structures in the prior art and the present application are given similar names and numbers.

In the prior art, the optical component 100 ' includes a signal line 10 ', the signal line 10 ' includes a first signal line 11 ' and a second signal line 12 ' that are distributed at intervals, the first signal line 11 ' is connected to the second signal line 12 ' through a first bonding wire 31 ', the first bonding wire 31 ' includes two first sub-bonding wires 31a ', and a gap between the two first sub-bonding wires 31a ' in the prior art is smaller than a gap between the two first sub-bonding wires 31a in the present application.

At this time, since the gap between the two first sub-bonding wires 31a 'is small in the prior art, there is a large mutual inductance between the two first sub-bonding wires 31 a', so that the impedance of the first bonding wire 31 'is large, and there is a sudden change in the link impedance at the first bonding wire 31'.

The gap between the two first sub-bonding wires 31a is large, so that the mutual inductance between the two first sub-bonding wires 31a can be reduced, the second bonding wire 32 is connected with the ground plane 20 to form electromagnetic shielding, the inductance of the first bonding wire 31 can be reduced, the impedance of the first bonding wire 31 is reduced, efficient transmission of signals in the signal wire 10 is facilitated, loss can be greatly reduced, transmission bandwidth is improved, and the high-frequency design requirement is met.

Specifically, referring to fig. 7, a diagram of an impedance simulation effect at the first bonding wire 31' (or the first bonding wire 31) in the prior art and the present application is shown.

The curve L1 represents the impedance at the first bond wire 31' in the prior art, which is about 57 ohms.

The curve L2 characterizes the impedance at the first bond wire 31 in this application, which is greater than 53 ohms.

It can be seen that the impedance at the first bond wire 31 of the present application is less than the impedance at the first bond wire 31' of the prior art.

Fig. 8 and 9 are combined to show simulation results of return loss and insertion loss in the prior art and the present application.

Curve M1 in fig. 8 characterizes the return loss of the prior art, curve M2 characterizes the return loss of the present application; n1 in fig. 9 characterizes the insertion loss of the prior art, and curve N2 characterizes the insertion loss of the present application.

It can be seen that the return loss and insertion loss of the present application are greatly improved compared to the prior art, so that the continuity of the link impedance can be increased, and the transmission loss can be effectively reduced.

Referring to fig. 10 and 11, the current distribution at the first bonding wire 31' (or the first bonding wire 31) in the prior art and the present application is shown.

Referring to fig. 10, in the prior art, since the impedance at the first bonding wire 31 'is large, so that the impedance of the link is discontinuous, the current flowing through the signal line 10' is reflected at the first bonding wire 31 '(see the current distribution at a in fig. 10), so that the current actually flowing through the signal line 10' becomes small, and the transmission of the signal is affected.

With reference to fig. 11, in the prior art, since the impedance at the first bonding wire 31 is small, so that the link impedance is continuous, the current flowing through the signal line 10 is not reflected at the first bonding wire 31, so that the current actually flowing through the signal line 10' remains unchanged, and the signal transmission performance is greatly improved.

The invention also provides a light module comprising the optical assembly 100 as described above.

In addition, the optical module may further include other components, such as an optical coupling device, an optical multiplexing/demultiplexing device, and the like, which may be determined according to the actual situation.

To sum up, the second bonding wire 32 of the present application is connected to the ground plane 20 to form an electromagnetic shield, and the second bonding wire 32 passes through the signal line 10 region where the first bonding wire 31 is disposed, so that the electromagnetic shield effect can be well radiated to the first bonding wire 31 region, the sensitivity of the first bonding wire 31 can be reduced, the impedance of the first bonding wire 31 can be reduced, the efficient transmission of signals in the signal line 10 can be facilitated, the loss can be greatly reduced, the transmission bandwidth can be improved, and the high-frequency design requirement can be met.

In addition, according to the present invention, a gap between the two first sub-bonding wires 31a is large enough to reduce mutual inductance between the two first sub-bonding wires 31a, reduce impedance, and further increase impedance continuity.

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.

Claims

1. An optical component is characterized by comprising a signal wire, a ground plane and a bonding wire, wherein the signal wire comprises a first signal wire and a second signal wire which are distributed at intervals, the bonding wire comprises a first bonding wire and at least one second bonding wire which are arranged adjacently, the first bonding wire is connected with the first signal wire and the second signal wire, the second bonding wire is connected with the ground plane, and at least part of the second bonding wire is suspended and covers above the signal wire.

2. The optical assembly of claim 1, wherein at least a portion of the second wire bonds is suspended over the first wire bonds.

3. The optical assembly of claim 1, wherein the ground plane comprises a left ground plane and a right ground plane on either side of the signal line, and the second bond wire connects the left ground plane and the right ground plane.

4. The optical assembly of claim 3, wherein the left ground plane comprises first and second spaced-apart left ground planes, the right ground plane comprises first and second spaced-apart right ground planes, and the bondline further comprises a third bondline connecting the first and second left ground planes and a fourth bondline connecting the first and second right ground planes.

5. An optical assembly according to claim 4, wherein one end of the second bond wire connects one of the first left ground plane and the second left ground plane and the other end of the second bond wire connects one of the first right ground plane and the second right ground plane.

6. The optical assembly of claim 5 wherein the bonding wires comprise four sets of second bonding wires connecting the first left and right ground planes, the second left and right ground planes, and the second left and right ground planes, respectively.

7. The optical assembly of claim 4, wherein the first bondwire comprises two first sub-bondwires having a first gap, and the third bondwire comprises two third sub-bondwires having a third gap, the first gap being greater than the third gap.

8. The optical assembly of claim 4, wherein the first wire bond comprises two spaced apart first sub-wire bonds, and a contact point of the first sub-wire bond to the signal line is located within 100 microns inward of an edge of the signal line.

9. The optical module of claim 1, comprising a first component and a second component spaced apart from each other, wherein the first signal line is located in the first component, the second signal line is located in the second component, and the first component and the second component are optical transceivers or circuit boards.

10. A light module comprising an optical assembly according to any one of claims 1-9.