CN113206065A

CN113206065A - Transition block and optical chip packaging base

Info

Publication number: CN113206065A
Application number: CN202110395252.9A
Authority: CN
Inventors: 章九林; 宁亚茹; 杨栋
Original assignee: Sindi Technologies Co ltd
Current assignee: Sindi Technologies Co ltd
Priority date: 2021-04-13
Filing date: 2021-04-13
Publication date: 2021-08-03

Abstract

The invention discloses a transition block and an optical chip packaging base, wherein the transition block comprises a block body made of SiC materials, the front surface of the block body is provided with a signal return path and a microstrip line, two sides of the block body are respectively provided with a metalized fixed groove, and the back surface of the block body is a gold-tin back surface. High efficiency, high compatibility, good coupling, reliable quality, high yield and low cost. The invention is applied to the technical field of 5G.

Description

Transition block and optical chip packaging base

Technical Field

The invention relates to the technical field of 5G, in particular to a transition block and an optical chip packaging base.

Background

The year 2020 is the beginning of 5G construction, and meanwhile, the country also develops the 5G construction as a national strategic direction from the top level design, and the 5G bears the mission of 'new capital construction', which drives trillion output. The ministry of industry and informatization, the state development and reform committee hope to promote the deep development of information consumption, by 2021, the scale of information consumption reaches 6 trillion yuan, the driving effect of information technology in the consumption field is obviously enhanced, the output of related fields is promoted to 15 trillion yuan, and the notification clearly promotes the construction of 5G.

The optical chip packaging base is used in an optical communication system as a key component in a light emitting device, and is a basic element with high precision and high performance which is important for linking a light emitting source, modulation and physical layer driving. As an optical communication device, the online life of a product is required to be more than 20 years, which provides very challenging severe requirements for the packaging of the optical device, and the requirements of dust prevention, water prevention, corrosion prevention and the like are needed in the structure, and index characteristics such as optical performance, electrical performance and the like are also required to be ensured under the conditions of high and low temperature resistance, double 85 resistance and the like in the environment. In addition to good optical signal coupling to reduce loss, high hermeticity and solderability requirements are also required in the art.

In the prior art, the optical chip on the optical chip packaging base and the high-speed interconnection line of the subsystem are interconnected through gold wire bonding, the parasitic effect of an inductor enables the bandwidth to be limited and narrowed, meanwhile, the impedance is increased, discontinuity is generated, the integrity of a high-speed signal is seriously influenced, the efficiency of a bonding lead is low, a special device, namely a gold wire ball welding machine, is required, the cost is high, the production difficulty is brought, the precision is difficult to control, and the yield is low.

Disclosure of Invention

Technical problem to be solved

A transition block and an optical chip packaging base solve the technical problems of high production cost, low bonding lead efficiency, low yield and the like.

(II) technical scheme

In order to solve the technical problem, the invention provides a transition block which comprises a block body made of SiC materials, wherein the front surface of the block body is provided with a signal return path and a microstrip line, two sides of the block body are respectively provided with a metalized fixed groove, and the back surface of the block body is a gold-tin back surface.

In a further improvement, the metalized fixing groove is semi-cylindrical.

In a further improvement, the microstrip line is processed on the front surface of the block body through PVD and etching processes.

The invention also discloses an optical chip packaging base, which adopts the following technical scheme:

an optical chip packaging base comprises a metal substrate, an RF lead and at least one DC lead, wherein the metal substrate is provided with at least two mounting holes and the transition block, a microstrip line is bonded with an optical chip, and the microstrip line is conducted with the RF lead;

the RF lead and the DC lead are respectively sleeved with a sintered glass mounting piece, and the RF lead and the DC lead are respectively detachably fixed in the mounting holes through the glass mounting pieces.

In a further improvement, the transition block is used for manufacturing a high-speed signal by using the ultrahigh-frequency SiC-based film.

In a further improvement, gold plating layers are respectively arranged on the metal substrate, the RF lead wire, the DC lead wire, the glass mounting piece and the transition block.

In a further improvement, a TEC thermoelectric refrigerator is further arranged on the metal substrate, a tungsten copper block is arranged on the TEC thermoelectric refrigerator, the optical chip is arranged on the tungsten copper block, and a PD monitoring chip is arranged on the base.

In a further improvement, the RF lead has a diameter of 0.2mm and the DC lead has a diameter of 0.33 mm.

In a further refinement, the glass mount is cylindrical or profiled.

In a further improvement, the glass mounting member has an expansion coefficient of 32 x 10 < -7 >/K to 56 x 10 < -7 >/K and a dielectric constant of 4 to 6.

(III) advantageous effects

The transition block is used on the optical chip packaging base, and the block body made of SiC material has the advantages of high heat conductivity, high breakdown field strength, high saturated electron drift rate, high bonding energy and the like, realizes the ultrahigh frequency characteristic in the circuit, and is easy to bond and conduct heat. The signal return path can be adjusted in area and size according to actual needs, is convenient and quick, and has the advantages of strong compatibility, low parasitic effect, easiness in impedance control, continuity maintenance, signal integrity guarantee and the like. The optical chip packaging structure can be manufactured into different shapes and sizes, meets the compatibility of different optical chip packages, is easy to replace according to requirements, and meets different functions. The metallization fixed slot is easily fixed when the eutectic welding, can not shift, and the reliability is high, and the yield is high. The back of piece body is the gold tin back, can grow through direct plating or film deposition, and processing is simple, can automize the paster during the equipment, and is efficient, and the quality is reliable, and the yield is high.

The transition block replaceable and movable high-speed microstrip line SiC-based transition block device adopts the eutectic welding process technology, can improve the product process yield, realizes rapid production and improves the productivity. The structure is simple, the assembly is convenient, the process difficulty is low, the process efficiency and the yield are higher, the material source is wide, the refining process is mature, and the cost is low. The flexibility of signal coupling of the transmission line in the laser can be effectively increased; the impedance change caused by the parasitic effect of the inductor is reduced, and the continuity of the impedance of the transmission line is enhanced; the ultrahigh frequency characteristic is improved; the cost is reduced, and the compatibility problem when the optical chips with different sizes are packaged is solved.

The optical chip packaging base comprising the transition block also has the advantages, and the description is omitted.

The optical chip package base of the present invention, the DC lead and the RF lead are collectively referred to as Pin pins. The DC lead wires can be combined randomly according to actual chip functions, can be 3, 4, 5, 6 and 7, and has the advantages of wide application range and flexibility, less material types, flexible application, low cost, realization of different functions and capability of solving the compatibility problem of large-size and small-size optical chip packaging.

Through the matching of the dielectric constant of the RF lead wire and the glass mounting part, the continuous impedance matching of 25 ohms, 50 ohms, 75 ohms and the like can be realized under the conditions of ultrahigh frequency and ultrahigh speed, so that the continuity of the impedance is enhanced, the coupling flexibility and performance of signals are effectively provided, and the integrity of the signals is ensured.

The optical chip packaging base is simple in structure and convenient and fast to assemble, and by means of a sintering process and the adoption of the sintered glass mounting piece, the defects of low yield and high cost of the traditional optical chip packaging base in the manufacturing process can be overcome, the manufacturing difficulty and the production cost can be effectively reduced, the yield and the market competitiveness of products are improved, and the purposes of rapid production and rapid delivery are achieved. The coupling performance of signals is effectively improved, the integrity of the signals is ensured, and the product competitiveness is improved.

Drawings

FIG. 1 is a schematic structural diagram of a base for an optical chip package according to an embodiment of the present invention;

FIG. 2 is an exploded view of FIG. 1;

FIG. 3 is a schematic structural diagram of a base for an optical chip package in the prior art;

fig. 4 is a schematic structural diagram of a transition block according to an embodiment of the present invention.

Detailed Description

The following detailed description of embodiments of the present invention is provided in connection with the accompanying drawings and examples. The following examples are intended to illustrate the invention but are not intended to limit the scope of the invention.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on those shown in the drawings, and are used only for convenience in describing the present invention and for simplicity in description, and do not indicate or imply that the referenced devices or elements must have a particular orientation, be constructed in a particular orientation, and be operated, and thus are not to be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

Referring to fig. 1 to 4, a transition block includes a block body 5 made of SiC material, a signal return path 51 and a microstrip line 52 are disposed on a front surface of the block body 5, metallization fixing grooves 6 are respectively disposed on two sides of the block body 5, and a back surface of the block body 5 is a gold-tin back surface.

The transition block of the embodiment is used on the optical chip packaging base, and the block body 5 made of the SiC material has the advantages of high heat conductivity, high breakdown field strength, high saturated electron drift rate, high bonding energy and the like, so that the ultrahigh frequency characteristic in the circuit is realized, and the bonding and the heat conduction are easy. The signal return path 51 can be adjusted in area and size according to actual needs, is convenient and quick, and has the advantages of strong compatibility, low parasitic effect, easy control of impedance, continuity maintenance, signal integrity guarantee and the like. The optical chip packaging structure can be manufactured into different shapes and sizes, meets the compatibility of different optical chip packages, is easy to replace according to requirements, and meets different functions. The metallization fixed slot 6 is easy to fix during eutectic welding, can not shift, and the reliability is high, and the yield is high. The back of the block body 5 is a gold-tin back, can grow through direct electroplating or thin film deposition, is simple to process, can automatically mount a chip during assembly, and has high efficiency, reliable quality and high yield.

The transition block replaceable and movable high-speed microstrip line SiC-based transition block device of the embodiment adopts an eutectic welding process technology, can improve the product process yield, realizes rapid production and improves the productivity. The structure is simple, the assembly is convenient, the process difficulty is low, the process efficiency and the yield are higher, the material source is wide, the refining process is mature, and the cost is low. The flexibility of signal coupling of the transmission line in the laser can be effectively increased; the impedance change caused by the parasitic effect of the inductor is reduced, and the continuity of the impedance of the transmission line is enhanced; the ultrahigh frequency characteristic is improved; the cost is reduced, and the compatibility problem when the optical chips with different sizes are packaged is solved.

Further, in one embodiment, the metalized seating groove 6 is semi-cylindrical.

Further, in an embodiment, the microstrip line 52 is processed on the front surface of the block body 5 through PVD and etching processes, the structure is simple, the block shape is easy to be eutectic-welded, automatic equipment can be adopted for assembly, mass production can be achieved, the efficiency is high, full-automatic control is achieved, and the yield is high.

Based on the combination of the above embodiments, in an embodiment, the transition block 12 is manufactured and processed, a VLSi chip-level semiconductor process physical vapor deposition technology is used for microstrip high-speed interconnection line metallization, then plasma and dry etching are used for processing the microstrip line 52 on the transition block 12, the size of the microstrip line 52 can be flexibly controlled according to actual needs, and coupling connection of optical chips with various sizes is facilitated. And then, the prepared transition block 12 is solidified on the step at the tail end of the RF lead 2 through an eutectic welding process, and gold-tin spot welding is used for interconnecting high-speed signal transmission lines, so that the integrity of high-speed signals is ensured.

In the transition block 12 of this embodiment, a SiC material is used as a dielectric material, and a high-frequency high-speed microstrip line film is deposited on the front surface of the block body 5 to grow a signal return path 51 and a microstrip line 52 with various required patterns, so as to implement signal coupling and transmission. The requirements of different characteristic impedances of ultrahigh frequency signals can be met by designing and controlling the length, width, height, size, shape and the like of the SiC material, and the interconnection function of high-speed signals is realized.

The transition block 12 is welded on the base in a eutectic welding mode and fixed, and the microstrip line 52 of the block body 5 is bonded with the optical chip 5 and conducted with the RF lead 2 on the metal substrate 1. The high-speed modulation optical signal is generated by loading the electrical modulation high-speed signal to the optical chip 5 or the active electrode on the optical modulator, and enters the optical network system to realize the optical signal transmission.

The high-speed microstrip line SiC-based thin film transition block is suitable for packaging laser optical chips and optical modulators with various sizes and volumes, can be reasonably and flexibly designed, applied and replaced according to different functions of actual chips in size and shape, is high in compatibility and simple in structure, improves the process yield and production efficiency of the whole optical assembly, and is lower in manufacturing cost.

The embodiment also discloses an optical chip packaging base, which adopts the following technical scheme:

an optical chip packaging base comprises a metal substrate 1, an RF lead wire 2 and at least one DC lead wire 3, wherein at least two mounting holes 11 and the transition block 12 are formed in the metal substrate 1, a microstrip line is bonded with an optical chip 5, the microstrip line is conducted with the RF lead wire 2, so that an electric modulation high-speed signal wire is realized, and the electric modulation high-speed signal wire is loaded onto an active electrode on the optical chip 5 to generate a high-speed optical signal.

The RF lead wire 2 and the DC lead wire 3 are respectively sleeved with a sintered glass mounting piece 4, and the RF lead wire 2 and the DC lead wire 3 are respectively detachably fixed in each mounting hole 11 through the glass mounting pieces 4.

The optical chip package base of the present embodiment, the DC lead 3 and the RF lead 2 are collectively referred to as PiN pins. The DC lead wires 3 can be combined randomly according to actual chip functions, and can be 3, 4, 5, 6 and 7, so that the application range and flexibility are increased, the material types are reduced, the flexible application is realized, the cost is reduced, different functions are realized, and the compatibility problem of large and small optical chip packaging is solved.

The RF lead 2 can realize continuous impedance matching of 25, 50, 75 ohms and the like under the conditions of ultrahigh frequency and ultrahigh speed through matching with the dielectric constant of the glass mounting part 4, so that the continuity of the impedance is enhanced, the coupling flexibility and performance of signals are effectively provided, and the integrity of the signals is ensured.

The optical chip packaging base of this embodiment, simple structure, equipment are convenient, with the help of sintering process, adopt the glass installed part 4 of sintering, can solve traditional optical chip packaging base processing procedure yield and low, defect with high costs, can effectively reduce the preparation degree of difficulty and manufacturing cost, improve product yield and market competition, reach the purpose of rapid production, rapid delivery. The coupling performance of signals is effectively improved, the integrity of the signals is ensured, and the product competitiveness is improved.

Further, in an embodiment, the transition block 12 is a microstrip plate for manufacturing a high-speed signal for the ultrahigh frequency SiC-based thin film, so that the high-speed performance of the interconnection line of the RF lead 2 is greatly enhanced, the bandwidth is wider, and the ultrahigh frequency bandwidth of 25GHz and over 50G can be realized. Preferably, gold and tin grow on the back of the microstrip plate, and the gold and tin can be directly eutectic technically, so that full-automatic and large-scale production is realized, the efficiency and yield are improved, the cost is reduced, and the competitiveness of products is improved. Specifically, the high-speed signal microstrip plate manufactured by the ultrahigh-frequency SiC-based film adopts semiconductor process physical vapor deposition and metallized pattern processing, is easy for batch production, reduces the process difficulty by adopting a photoetching technology, and has strong consistency and stable performance.

Further, in an embodiment, gold plating layers are respectively disposed on the metal substrate 1, the RF lead 2, the DC lead 3, the glass mount 4 and the transition block 12, and the gold plating layers have an anti-corrosion function.

Further, in an embodiment, a TEC thermoelectric refrigerator 13 is further disposed on the metal substrate 1, a tungsten copper block 14 is disposed on the TEC thermoelectric refrigerator 13, and an optical chip 5 or an optical modulation chip is disposed on the tungsten copper block 14. The PD monitoring chip 15 is a PD chip, and the optical chip 5 is a Laser chip optical chip. The TEC thermoelectric refrigerator 13 has the advantages of heat dissipation and heat conduction performance, strong compatibility, simple structure, improved component manufacturing process yield, higher efficiency and lower manufacturing cost.

Further, in an embodiment, the TEC thermoelectric refrigerator 13 is provided with a tungsten copper block 14, the optical chip 5 is provided on the tungsten copper block 14, the tungsten copper block 14 is used for covering the optical chip 5, and the PD monitoring chip 15 is on the TEC thermoelectric refrigerator 13.

Further, in one embodiment, the RF lead 2 has a diameter of 0.2mm and the DC lead 3 has a diameter of 0.33 mm. Fix RF lead wire 2 in the glass installed part 4 of the mounting hole 11 of metal substrate 1, with the sintering of glass installed part 4 to certain expansion coefficient matches for RF lead wire 2 is fine fixed, and guarantees the gas tightness, simple structure, and the equipment is also very convenient, and the processing procedure is efficient, and the yield is high.

Further, in an embodiment, the glass mount 4 is cylindrical or shaped, and the glass mount 4 may be shaped as desired as shown in fig. 1-2.

Further, in one embodiment, the glass mounting member 4 has an expansion coefficient of 32 × 10-7/K to 56 × 10-7/K and a dielectric constant of 4 to 6.

Based on the combination of the above embodiments, in an embodiment, the microstrip board of the high-speed signal made of the ultrahigh frequency SiC-based thin film is metalized with a high-speed interconnection line by using a VLSi chip-level semiconductor process physical vapor deposition epitaxial growth technology, and a pattern on the transition block 12 is processed by using plasma and dry etching. The method comprises the following steps that 7 DC leads 3 made of special materials are distributed and inserted into 7 mounting holes 11 in an annular arrangement mode, another DC lead 3 is used as a grounding wire and brazed to the bottom of a stamping part to be grounded, and meanwhile, glass mounting pieces 4 on the DC leads 3 are fastened through insulators with expansion coefficients matched strictly and high-airtightness sintering processes of 800-1000 ℃ and metal, so that air leakage cannot occur in a certain air pressure environment, and certain air tightness is guaranteed. The entire base of the optical chip package (including the metal substrate 1, the RF leads 2, the DC leads 3, the glass mount 4, and the transition block 12) is then subjected to pure gold plating to form a gold plating layer on the surface thereof, thereby ensuring corrosion resistance and reducing loss. The 7 DC leads 3 can be combined and matched at will according to actual chip function requirements, for example, only 3, 4, 5 and 6 are used, flexible application is realized, and different Pin function requirements are met. And then, the prepared transition block 12 is solidified on the step at the tail end of the RF lead 2 through an eutectic welding process, and gold-tin spot welding is used for interconnecting high-speed signal transmission lines, so that the integrity of high-speed signals is ensured.

The above description is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, several modifications and variations can be made without departing from the technical principle of the present invention, and these modifications and variations should also be regarded as the protection scope of the present invention.

Claims

1. The transition block is characterized by comprising a block body made of SiC materials, wherein a signal return path and a microstrip line are arranged on the front surface of the block body, metalized fixing grooves are respectively formed in two sides of the block body, and the back surface of the block body is a gold-tin back surface.

2. The transition block of claim 1, wherein the metalized seating groove is semi-cylindrical.

3. The transition block of claim 1, wherein the microstrip line is formed on the front surface of the block body by PVD and etching.

4. An optical chip package base, comprising a metal substrate, an RF lead and at least one DC lead, wherein the metal substrate is provided with at least two mounting holes and a transition block according to any one of claims 1 to 3, the microstrip line is bonded to an optical chip, and the microstrip line is conducted to the RF lead;

5. The optical chip package base of claim 4, wherein the transition block is a transition block for fabricating high speed signals from ultra high frequency SiC based thin films.

6. The optical chip package base of claim 4, wherein the metal substrate, the RF leads, the DC leads, the glass mount and the transition block are each provided with a gold plating.

7. The optical chip package base according to claim 4, wherein the metal substrate is provided with a TEC thermoelectric cooler, the TEC thermoelectric cooler is provided with a tungsten copper block, the optical chip is provided on the tungsten copper block, and the base is provided with a PD monitoring chip.

8. The photonic chip package base of any of claims 4 to 7, wherein the RF lead has a diameter of 0.2mm and the DC lead has a diameter of 0.33 mm.

9. The optical chip package base of any one of claims 4 to 7, wherein the glass mount is cylindrical or shaped.

10. The optical chip package base according to any one of claims 4 to 7, wherein the glass mounting member has an expansion coefficient of 32 x 10 "7/K to 56 x 10" 7/K and a dielectric constant of 4 to 6.