CN208707072U - A kind of high-reliable semiconductor laser of low stress encapsulation - Google Patents
A kind of high-reliable semiconductor laser of low stress encapsulation Download PDFInfo
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- CN208707072U CN208707072U CN201821756440.XU CN201821756440U CN208707072U CN 208707072 U CN208707072 U CN 208707072U CN 201821756440 U CN201821756440 U CN 201821756440U CN 208707072 U CN208707072 U CN 208707072U
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Abstract
A kind of high-reliable semiconductor laser of low stress encapsulation, comprising: main heat sink, insulating trip, negative electrode tab, cathode briquetting and bar unit.It is secondary heat sink to be made of the coefficient of expansion and the matched Tungsten-copper Composites of bar item or molybdenum material, its mutual matched coefficients of thermal expansion, therefore the encapsulation stress of bar item can be reduced, it can avoid causing encapsulation stress excessive because of coefficient of thermal expansion mismatch, to generate more serious near field nonlinear effect or even make laser fails.The upper and lower ends of bar item are welded with time heat sink, compared with bar Direct Bonding gold thread, pass through the secondary heat sink heat-sinking capability for being bonded with negative electrode tab gold thread and the face N of bar item can be improved while reducing encapsulation stress.Encapsulation stress is reduced, the breakage of encapsulation process mini-bus item is effectively prevented, reduces operation difficulty, improves encapsulation qualification rate.Meanwhile bar item is welded using golden tin hard solder, is avoided the electromigration and electric heating migration of the generation of indium solder, is substantially increased the reliability of laser.
Description
Technical field
The utility model relates to semiconductor laser fields, and in particular to a kind of high reliability half of low stress encapsulation
Conductor laser.
Background technique
In recent years high-power semiconductor laser by its small in size, light weight, photoelectric conversion efficiency is high, performance is stable and
The advantages that service life is long is widely used in the fields such as industry, communication, military, medical treatment and material surface processing.With semiconductor material
The rapid development for expecting the technologies such as growth technology, quantum well structure optimisation technique, low ohm contact technique, low thermal resistance, has
High power, high efficiency, high brightness semiconductor laser developed rapidly, it is right but simultaneously with the development of application field
More stringent requirements are proposed for the performance of semiconductor laser.High-power optical-fiber coupling product and optical shaping product requirement semiconductor
Laser has the features such as extremely low chip curvature, i.e. " smile " effect of very little, high reliability and long-life, it is ensured that
The long-term stable operation of high-power semiconductor laser, this brings greatly to semiconductor laser chip itself and encapsulation technology
Challenge.
Except having outside the Pass with the design of this body structure of chip, the reliability and encapsulating structure of semiconductor laser have substantial connection.
It is most of using a bar item encapsulation for the high power for obtaining tens watts of even upper hectowatts since single-chip continuous power output is limited
Form is realized.For the heating conduction for improving laser, generallys use the higher oxygenless copper material of thermal conductivity and be packaged, oxygen-free copper
Although thermal conductivity is relatively high, thermally conductive fast, its thermal expansion coefficient is 2-3 times of semiconductor laser chip, after packaging can be
Biggish stress is generated on bar item, causes " smile " larger, is not easy to subsequent optical alignment, while its reliability can also drop
It is low.For the stress for reducing oxygen-free copper encapsulation, it is necessary to be welded using the slicken solder indium solder that can discharge stress, but indium solder
Electromigration and electric heating migration can be generated under high current conditions, are formed cavity, are influenced heat dissipation and the long-term reliability of laser.Cause
This, for the long-term reliability for improving laser, it is necessary to which encapsulation stress is reduced using effective technological means.
Chinese patent literature CN203747263U discloses a kind of high-power semiconductor laser of low stress structure, including
Four-layer structure is stacked gradually, first layer is as the heat sink of positive link block, and the second layer is chip and insulating trip, and third layer is
The connection electrode layer of electric action is played, the 4th layer is cathode link block, in connection electrode layer, is welded with semiconductor laser chip
Position be plane dentate structure, the stress between connection electrode layer and chip can be reduced.But since connection electrode layer is copper
Material, the welding with bar item must discharge stress, poor reliability, moreover, because course of work mini-bus P using slicken solder
Face is different with N face contact material or material thickness is different, can also generate biggish stress.
Chinese patent literature CN106329308A discloses the capsulation structure for semiconductor laser of low smile a kind of, passes through
Respectively add one layer of symmetrical stress slow release layer in heat sink top and bottom, the thermal expansion coefficient of stress slow release layer is matched with a bar item, material
For tungsten copper or graphite copper or graphitized alumina or graphene or copper diamond or ceramic copper-clad structure, so that heat sink corresponding strain up and down
Shrinkage is consistent, can reduce encapsulation stress.But since bar face N is the scope of freedom, the stress being subject to and the face P are asymmetric
, thus the stress being subject on entire bar of item be it is non-uniform, reliability is poor, moreover, stress slow release layer thermal conductivity is lower,
It will limit the continuous power output of laser.
For improve high-power semiconductor laser long-term reliability, while reducing encapsulation stress, bar item it is direct
Welding must avoid the use of indium solder, and golden tin hard solder fusing point with higher, good thermally conductive, conductive characteristic, anti-corruption
Corrosion, without heat fatigue and can realize flux-free welding the advantages that, the height for being employed in high-power semiconductor laser can
In property and flux-free welding, and its fusing point is higher, is relatively suitble to the primary welding of bar item.But golden tin hard solder belongs to firmly
Solder, it is not easy to encapsulation stress is discharged, to reduce encapsulation stress, when using golden tin hard solder progress bar item encapsulation, it is necessary to adopt
With thermal expansion coefficient and the matched material of bar item.
Summary of the invention
The utility model provides one kind and encapsulation stress is effectively reduced, improves and partly leads to overcome the shortcomings of the above technology
The high-reliable semiconductor laser of the low stress encapsulation of body laser reliability.
The utility model overcomes the technical solution used by its technical problem to be:
A kind of high-reliable semiconductor laser of low stress encapsulation, comprising:
Master is heat sink, and insulating trip is transversely welded on upper surface；
Negative electrode tab is transversely fixedly welded on the upper surface of insulating trip；
Cathode briquetting, is fixedly welded on the upper surface of negative electrode tab；And
Bar unit, by two parallel time it is heat sink and be clipped on two times it is heat sink between a bar item form, bar
Two sides pass through golden tin hard solder respectively and fix with ipsilateral secondary heat sink welding above and below item, its is longitudinally disposed for bar unit, described
The side of the neighbouring bar unit of negative electrode tab is vertically arranged with step, and the secondary heat sink welding positioned at lower end is fixed on main heat sink upper table
On face, time heat sink be bonded by gold thread positioned at upper end is connected with step, and described time heat sink using Tungsten-copper Composites or molybdenum material
It is made；
The cooling water channel of same axis is respectively arranged on main heat sink, insulating trip, negative electrode tab and cathode briquetting.
Preferably, above-mentioned master is heat sink is made of oxygenless copper material, and main heat sink outer surface is coated with the gold that material is nickel or gold
Belong to layer.
Preferably, positioned at the time heat sink of lower end with it is main it is heat sink between pass through tin-silver-copper solder or indium solder or indium tin solder etc.
Solder is welded.
Preferably, insulating trip and it is main it is heat sink between welded by tin-silver-copper solder or the solders such as indium solder or indium tin solder
It connects.
Preferably, it is welded between negative electrode tab and insulating trip by tin-silver-copper solder or the solders such as indium solder or indium tin solder
It connects.
Preferably, it is carried out between cathode briquetting and negative electrode tab by tin-silver-copper solder or the solders such as indium solder or indium tin solder
Welding.
Preferably, insulating trip is made of potsherd or pcb board, and negative electrode tab is made of copper product, insulating trip and cathode
Piece outer surface is coated with the metal layer that material is nickel or gold.
Preferably, above-mentioned two time heat sink outer dimension is equal, and secondary heat sink length is 1.05 times of bar length-
1.1 times, secondary heat sink width is 1.05 times -1.1 times of bar width, secondary heat sink 2 times -4 times with a thickness of bar thickness, bar
Item is located at two heat sink middle positions.
Preferably, the upper surface flush of the upper surface of above-mentioned bar of unit and step.
The beneficial effects of the utility model are: secondary heat sink for the coefficient of expansion and the matched Tungsten-copper Composites of bar item or molybdenum material system
At, mutual matched coefficients of thermal expansion, therefore the encapsulation stress of bar item can be reduced, it can avoid causing because of coefficient of thermal expansion mismatch
Encapsulation stress is excessive, to generate more serious near field nonlinear effect or even make laser fails.The upper and lower ends of bar item are equal
Be welded with it is time heat sink, compared with bar Direct Bonding gold thread, by it is secondary it is heat sink be bonded gold thread with negative electrode tab can be in reduction encapsulation
The heat-sinking capability in the face N of bar item can be improved while stress.Encapsulation stress is reduced, encapsulation process mini-bus item is effectively prevented
Breakage reduces operation difficulty, improves encapsulation qualification rate.Meanwhile bar item is welded using golden tin hard solder, avoids indium
The electromigration and electric heating migration that solder generates, substantially increase the reliability of laser.
Detailed description of the invention
Fig. 1 is the exploded perspective structural schematic diagram of the utility model；
Fig. 2 is the schematic perspective view of bar unit of the utility model；
In figure, 1. main 3. insulating trip of heat sink 2. bars of units, 4. negative electrode tab, 5. cathode briquetting, 6. step, 7. cooling waters
2.1 bars of channel item 2.2 times is heat sink.
Specific embodiment
With reference to the accompanying drawing 1, attached drawing 2 is described further the utility model.
A kind of high-reliable semiconductor laser of low stress encapsulation, comprising: lead heat sink 1, transversely welded on upper surface
It connects and is fixed with insulating trip 3；Negative electrode tab 4 is transversely fixedly welded on the upper surface of insulating trip 3；Cathode briquetting 5, welding
It is fixed on the upper surface of negative electrode tab 4；And bar unit 2, heat sink 2.2 and two are clipped on parallel time by two
Bar item 2.1 between secondary heat sink 2.2 forms, and about 2.1 two sides of bar item pass through golden tin hard solder and ipsilateral secondary heat sink 2.2 respectively
It is welded and fixed, its is longitudinally disposed for bar unit 2, and the side of the neighbouring bar unit 2 of negative electrode tab 4 is vertically arranged with step 6, position
Be fixedly welded on main heat sink 1 upper surface in times heat sink the 2.2 of lower end, times heat sink 2.2 positioned at upper end be bonded by gold thread and
Step 6 is connected, and secondary heat sink 2.2 are made of Tungsten-copper Composites or molybdenum material；Main heat sink 1, insulating trip 3, negative electrode tab 4 and cathode
The cooling water channel of same axis is respectively arranged on briquetting 5.Secondary heat sink 2.2 be the coefficient of expansion and the matched Tungsten-copper Composites of bar item 2.1
Or molybdenum material is made, mutual matched coefficients of thermal expansion, therefore can reduce the encapsulation stress of bar item, can avoid because of thermal expansion system
Number mismatch causes encapsulation stress excessive, to generate more serious near field nonlinear effect or even make laser fails.Bar item 2.1
Upper and lower ends be welded with times heat sink 2.2, compared with 2.1 Direct Bonding gold thread of bar item, pass through secondary heat sink 2.2 and negative electrode tab 4
The heat-sinking capability in the face N of bar item 2.1 can be improved in bonding gold thread while reducing encapsulation stress.Encapsulation stress is reduced,
The breakage for effectively preventing encapsulation process mini-bus item 2.1, reduces operation difficulty, improves encapsulation qualification rate.Meanwhile bar item
2.1 are welded using golden tin hard solder, are avoided the electromigration and electric heating migration of the generation of indium solder, are substantially increased laser
Reliability.
Embodiment 1:
Above-mentioned master heat sink 1 is made of oxygenless copper material, and main heat sink 1 outer surface is coated with the metal layer that material is nickel or gold.
Main heat sink 2 its thermal conductivity made of oxygenless copper material are higher, the heat-sinking capability of laser can be improved, by outside master heat sink 1
Surface be coated with material be nickel or gold metal layer can be improved its surface welding when solder between affinity, to improve weldering
Connect performance.
Embodiment 2:
It is welded between secondary heat sink the 2.2 of lower end and main heat sink 1 by tin-silver-copper solder or indium solder or indium tin solder etc.
Material is welded.Pass through golden tin hard solder welding encapsulation due to passing through bar unit 2 between bar item 2.1 and secondary heat sink 2.2, can keep away
Exempt from failure caused by the electromigration and electric heating migration of indium solder under high current conditions, improves the reliability of laser.Bar item
Using the tin-silver-copper solder or the solders such as indium solder or indium tin solder that the golden tin hard solder of fusing point is low between unit 2 and main heat sink 1
It carries out welding and carries out secondary welding, formation temperature gradient avoids the secondary fusion of golden tin hard solder.
Embodiment 3:
It is welded between insulating trip 3 and main heat sink 1 by tin-silver-copper solder or the solders such as indium solder or indium tin solder, absolutely
Embolium 3 and main heat sink 1 firm welding degree are higher, avoid because there are problems that bonding loosely shifts using adhesive tape bonding.
Embodiment 4:
It is welded, is born by tin-silver-copper solder or the solders such as indium solder or indium tin solder between negative electrode tab 4 and insulating trip 3
Pole piece 4 and 3 firm welding degree of insulating trip are higher, avoid because there are problems that bonding loosely shifts using adhesive tape bonding.
Embodiment 5:
It is welded between cathode briquetting 5 and negative electrode tab 4 by tin-silver-copper solder or the solders such as indium solder or indium tin solder,
Cathode briquetting 5 and 4 firm welding degree of negative electrode tab are higher, avoid because there are problems that bonding loosely shifts using adhesive tape bonding.
Embodiment 6:
Insulating trip 3 is made of potsherd or pcb board, and negative electrode tab 4 is made of copper product, outside insulating trip 3 and negative electrode tab 4
Surface is coated with the metal layer that material is nickel or gold.By being coated with the gold that material is nickel or gold in insulating trip 3 and 4 outer surface of negative electrode tab
Belong to layer can be improved its surface welding when solder between affinity, to improve welding performance.
Embodiment 7:
Two times heat sink 2.2 outer dimension is equal, and secondary heat sink 2.2 length is 1.05 times -1.1 of 2.1 length of bar item
Times, secondary heat sink 2.2 width is 1.05 times -1.1 times of 2.1 width of bar item, secondary heat sink 2.2 with a thickness of the 2 of 2.1 thickness of bar item
- 4 times again, bar item 2.1 is located at two times heat sink 2.2 middle positions.The two times heat sink 2.2 equal certifiable burnings of outer dimension
Two times heat sink 2.2 deflections are consistent during knot, thus keep the face P of bar item 2.1 consistent with the face N stress, the encapsulation of introducing
Stress is smaller.And secondary heat sink 2.2 with a thickness of 2 times -4 times of 2.1 thickness of bar item, and it is excessively thin both to can avoid heat sink 2.2 thickness of dimension
Cause deflection excessive, also can avoid the blocked up problem for leading to heat-sinking capability difference of heat sink 2.2 thickness of dimension.Secondary heat sink 2.2 size
It is can effectively protect 2.1 edge of bar item convenient for a bar clamping for unit 2 slightly larger than 2.1 size of bar item, 2.1 edge of bar item is avoided to touch
It is bad, damaged.
Embodiment 8:
The upper surface of bar unit 2 and the upper surface flush of step 6.Can avoid gold thread it is too long cause to collapse line the problem of,
Design step 6 can make the top face of the gold thread height lower than negative electrode tab 4, effective protection gold thread.
Claims (9)
1. a kind of high-reliable semiconductor laser of low stress encapsulation characterized by comprising
It leads heat sink (1), is transversely welded with insulating trip (3) on upper surface；
Negative electrode tab (4), is transversely fixedly welded on the upper surface of insulating trip (3)；
Cathode briquetting (5), is fixedly welded on the upper surface of negative electrode tab (4)；And
Bar unit (2), by two parallel time heat sink (2.2) and bar being clipped between two times heat sink (2.2)
Item (2.1) composition, two sides pass through golden tin hard solder to bar item (2.1) respectively up and down and ipsilateral secondary heat sink (2.2) are welded and fixed, bar
Its is longitudinally disposed for unit (2), and the side of the neighbouring bar unit (2) of the negative electrode tab (4) is vertically arranged with step (6),
It is fixedly welded on main heat sink (1) upper surface positioned at time heat sink (2.2) of lower end, time heat sink (2.2) positioned at upper end pass through gold
Line bonding is connected with step (6), is made of Tungsten-copper Composites or molybdenum material for described time heat sink (2.2)；
The cooling water channel of same axis is respectively arranged on main heat sink (1), insulating trip (3), negative electrode tab (4) and cathode briquetting (5).
2. the high-reliable semiconductor laser of low stress encapsulation according to claim 1, it is characterised in that: the main heat
Heavy (1) is made of oxygenless copper material, and main heat sink (1) outer surface is coated with the metal layer that material is nickel or gold.
3. the high-reliable semiconductor laser of low stress encapsulation according to claim 1, it is characterised in that: be located at lower end
Time heat sink (2.2) welded by tin-silver-copper solder or the solders such as indium solder or indium tin solder between heat sink (1) with leading.
4. the high-reliable semiconductor laser of low stress encapsulation according to claim 1, it is characterised in that: insulating trip
(3) it is welded between main heat sink (1) by tin-silver-copper solder or the solders such as indium solder or indium tin solder.
5. the high-reliable semiconductor laser of low stress encapsulation according to claim 1, it is characterised in that: negative electrode tab
(4) it is welded between insulating trip (3) by tin-silver-copper solder or the solders such as indium solder or indium tin solder.
6. the high-reliable semiconductor laser of low stress encapsulation according to claim 1, it is characterised in that: cathode briquetting
(5) it is welded between negative electrode tab (4) by tin-silver-copper solder or the solders such as indium solder or indium tin solder.
7. the high-reliable semiconductor laser of low stress encapsulation according to claim 1, it is characterised in that: insulating trip
(3) it is made of potsherd or pcb board, negative electrode tab (4) is made of copper product, insulating trip (3) and the plating of negative electrode tab (4) outer surface
Having material is the metal layer of nickel or gold.
8. the high-reliable semiconductor laser of low stress encapsulation according to claim 1, it is characterised in that: described two
The outer dimension of secondary heat sink (2.2) is equal, and the length of secondary heat sink (2.2) is 1.05 times -1.1 times of bar item (2.1) length, secondary heat
The width of heavy (2.2) is 1.05 times -1.1 times of bar item (2.1) width, secondary heat sink (2.2) with a thickness of a bar item (2.1) thickness
2 times -4 times, bar item (2.1) is located at two times heat sink (2.2) middle positions.
9. the high-reliable semiconductor laser of low stress encapsulation according to claim 1, it is characterised in that: described bar of item
The upper surface of unit (2) and the upper surface flush of step (6).
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| CN201821756440.XU CN208707072U (en) | 2018-10-29 | 2018-10-29 | A kind of high-reliable semiconductor laser of low stress encapsulation |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN112821187A (en) * | 2020-12-30 | 2021-05-18 | 西安立芯光电科技有限公司 | Single-bar packaging method for semiconductor laser |
| CN114284857A (en) * | 2021-11-25 | 2022-04-05 | 佛山华智新材料有限公司 | Secondary heat sink and liquid cooling heat sink integration method, integrated heat sink and application |
| CN114361933A (en) * | 2021-12-08 | 2022-04-15 | 中国电子产品可靠性与环境试验研究所（（工业和信息化部电子第五研究所）（中国赛宝实验室）） | Semiconductor laser heat radiation structure and packaging structure with same |
| CN114406460A (en) * | 2022-01-07 | 2022-04-29 | 苏州尤诗光电科技有限公司 | Laser bar packaging structure, welding fixture and method |
| CN115106671A (en) * | 2022-08-22 | 2022-09-27 | 度亘激光技术（苏州）有限公司 | Packaging method and packaging clamp |
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2018
- 2018-10-29 CN CN201821756440.XU patent/CN208707072U/en active Active
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN112821187A (en) * | 2020-12-30 | 2021-05-18 | 西安立芯光电科技有限公司 | Single-bar packaging method for semiconductor laser |
| CN114284857A (en) * | 2021-11-25 | 2022-04-05 | 佛山华智新材料有限公司 | Secondary heat sink and liquid cooling heat sink integration method, integrated heat sink and application |
| CN114284857B (en) * | 2021-11-25 | 2023-11-17 | 佛山华智新材料有限公司 | Method for integrating secondary heat sink and liquid cooling heat sink, integrated heat sink and application |
| CN114361933A (en) * | 2021-12-08 | 2022-04-15 | 中国电子产品可靠性与环境试验研究所（（工业和信息化部电子第五研究所）（中国赛宝实验室）） | Semiconductor laser heat radiation structure and packaging structure with same |
| CN114406460A (en) * | 2022-01-07 | 2022-04-29 | 苏州尤诗光电科技有限公司 | Laser bar packaging structure, welding fixture and method |
| CN115106671A (en) * | 2022-08-22 | 2022-09-27 | 度亘激光技术（苏州）有限公司 | Packaging method and packaging clamp |
| CN115106671B (en) * | 2022-08-22 | 2022-11-25 | 度亘激光技术（苏州）有限公司 | Packaging method and packaging clamp |
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