CN111224314A

CN111224314A - Self-indication surface-mounted semiconductor laser and packaging method thereof

Info

Publication number: CN111224314A
Application number: CN201811415327.XA
Authority: CN
Inventors: 王友志; 秦华兵; 尚秀涛; 郑兆河
Original assignee: Weifang Huaguang Photoelectronics Co ltd
Current assignee: Weifang Huaguang Photoelectronics Co ltd
Priority date: 2018-11-26
Filing date: 2018-11-26
Publication date: 2020-06-02

Abstract

The invention relates to a self-indicating surface-mounted semiconductor laser and a packaging method thereof, wherein the self-indicating surface-mounted semiconductor laser comprises a tube seat and a tube cap arranged on the tube seat, wherein in a space formed by the tube seat and the tube cap, the tube seat is sequentially provided with a COS (chip on chip), a 45-degree right-angle semi-reflecting platform, a crystal and a 45-degree right-angle total reflecting platform along a light path; the tube seat is provided with 2 45-degree reflecting modules, the first 45-degree reflecting module (45-degree right-angle semi-reflecting table) reflects 50% of laser to enable the light path to be changed by 90 degrees, the laser can be emitted out perpendicular to the tube seat and can also transmit 50% of laser, crystals are arranged on the light path, 808nm laser is pumped into 1064nm laser and then passes through a frequency doubling crystal to generate 532nm laser green laser, the light path is changed by 90 degrees after the green laser passes through the second 45-degree reflecting module (45-degree right-angle total reflecting table), and the laser is emitted perpendicular to the tube seat.

Description

Self-indication surface-mounted semiconductor laser and packaging method thereof

Technical Field

The invention relates to a self-indicating surface-mounted semiconductor laser and a packaging method thereof, belonging to the technical field of packaging and manufacturing of semiconductor lasers.

Background

The semiconductor laser has the advantages of small volume, light weight, low cost, long service life, selectable wavelength, stable output power, simple power supply driving system and the like, and the semiconductor laser technology is more mature in recent years and is more and more widely applied in the fields of industry and the like. The semiconductor laser has the advantages of small volume, long service life and the like, and can adopt a simple current injection mode to pump the working voltage and current of the semiconductor laser to be compatible with an integrated circuit, so that the semiconductor laser can be integrated with the integrated circuit in a single chip. Also, current modulation can be directly performed with frequencies up to GHz to obtain high-speed modulated laser output. Because of these advantages, semiconductor diode lasers have found wide applications in laser communication, optical storage, optical gyros, laser printing, ranging, and radar, among others. The range of semiconductor laser applications in clinical medicine is also becoming wider and wider. Therefore, the share of the compound in the market is larger and larger, and the compound has a very wide development prospect. The development of semiconductor laser devices has been mainly focused on developed countries such as the united states, europe, japan, and the like, and the development of instruments has been progressing toward miniaturization, integration, multifunction, and intelligence.

The semiconductor laser is mainly provided with two packaging forms at present, one is a TO packaging structure, TO packaging is adopted for general application with low power, and the packaging structure is suitable for most application occasions in a pluggable mode, but the packaging structure cannot be applied TO narrow space, especially flat space, due TO the fact that a tube tongue is long in the light emitting direction, and the miniaturization design of a module is not facilitated; the other type is C-mount packaging, generally high-power packaging above W level, and has the advantages of high reliability, high stability, high-precision machining and high heat conductivity, but the defects that although the structure is flat, the PCB (printed circuit board) cannot be directly pasted with an electrified shell, so that the requirement of small modularization cannot be met, and no protective window exists, so that the packaging can not be applied to certain specific severe environments. Most of the existing semiconductor lasers are single-wavelength lasers, indicating light needs to be provided when the semiconductor lasers are subsequently connected with optical fiber coupling output for application, the working current of the indicating light lasers is low, and the high-energy infrared light fed back by a light path and electric leakage are easy to cause failure in the specific using process, so that the normal work of a laser system of equipment is influenced.

Chinese patent document CN103633552B discloses a patch laser packaging structure and a packaging method thereof in an optoelectronic circuit, and discloses an L-shaped patch packaged laser and a packaging method thereof. The surface mount laser packaging structure comprises a semiconductor laser tube core and an L-shaped heat sink; the L-shaped heat sink comprises an L-shaped negative electrode layer, an L-shaped insulating layer and an L-shaped positive electrode layer, wherein an L-shaped groove is formed in the inner surface of the L-shaped negative electrode layer, the L-shaped positive electrode layer is embedded into the L-shaped groove, and the L-shaped insulating layer is arranged between the L-shaped negative electrode layer and the L-shaped positive electrode layer; the semiconductor laser tube core is arranged on the inner surface of the L-shaped negative electrode layer and is not provided with an L-shaped groove. The structure has the advantages of small volume, high reliability, low welding spot defect rate and the like, but the light emitting direction of the laser can only be emitted in parallel to the PCB, the laser electrode is directly welded on the PCB from the tube core, the reliability of a gold thread is sharply reduced after the gold thread is elongated, the use in severe environments is not facilitated without the protection of a tube cap, and the pure patch type packaging is not easy to replace and is not beneficial to later maintenance.

A patch laser disclosed in chinese patent document CN103904533B, which relates to a patch laser, comprising the following parts: a positive electrode conductive block; a negative conductive block; positioning a groove; an internal positive electrode lead; an LD chip; the positions and the connection relations among the components are as follows: the positive electrode conducting block and the negative electrode conducting block are used as 2 bottom layer conducting and heat dissipating blocks, the LD chip is glued on the upper surface of the negative electrode conducting block, and the internal positive electrode lead is connected between the LD chip and the positive electrode conducting block to play a role in conducting connection; the positioning groove wraps the positive and negative electrode conductive blocks and the LD chip, so that a surface mount laser is formed; when in use, the laser is welded on the positive and negative electrode welding pads of the circuit board. The laser has the advantages of extremely small volume, convenience for chip packaging and the like, but the laser is emitted in the horizontal direction and cannot meet the application in the vertical direction, and the pure chip packaging is more difficult to maintain than direct-insert welding in the later period.

Chinese patent document CN 245165 discloses a package structure of a semiconductor laser, which has a metal positive lead frame, which has a first lead, a base is combined on the first lead, a laser chip is combined on the base, a negative lead frame is arranged on one side of the positive lead frame, a second lead is arranged at the rear end of the negative lead frame, a predetermined distance is provided between the negative lead frame and the positive lead frame, and one end of a lead is connected to the negative lead frame, the other end of the lead is connected to the laser chip, and the positive and negative lead frames are covered with a transparent cover at the outer side combining the base, the laser chip and one end of the lead, thereby having the advantage of simple structure. This packaging structure has realized a laser instrument from instructing encapsulation form, however, this patent increased the location of semiconductor laser chip among the packaging structure to realize producing the fixed dimension interval between positive wire frame of metal and the negative wire frame of metal, need very high assembly precision, and luminous direction still is the unable requirement that satisfies perpendicular light of horizontal direction.

Chinese patent document CN102662240A provides a multi-light-emitting unit semiconductor laser module coupling device with indication. The coupling device of the multi-light-emitting unit semiconductor laser module comprises a plurality of semiconductor laser modules and an indicating module, wherein the semiconductor laser modules and the indicating module are fixedly arranged on a circuit board, and the indicating module adopts a visible light semiconductor laser chip; the output of each light-emitting unit in each semiconductor laser module group is respectively connected with the optical fiber jumpers corresponding to the light-emitting units one by one, and the output of the indicating module is also connected with the independent optical fiber jumpers; all the optical fiber jumpers form combined beam output in a physical convergence mode. The invention makes the laser module not need to carry out complex beam shaping, and realizes high-power output and uniform light spots with lower cost and simple and convenient arrangement. However, the indicating light and the working laser of the device are different lasers, and the simultaneous power supply cannot be achieved, so that the possibility of abnormal operation caused by circuit faults is increased.

In summary, in the existing laser used in the market, especially in the market of the miniaturized application, the two lasers with the indicating light are generally realized by optical beam combination, because the two independent lasers need to be independently powered, the working currents required by the high-power laser and the indicating light laser are not consistent, and the indicating laser is easily burned off by the drain electrode of the high-power laser, the stability is affected by the equipment failure. The packaging form of the laser is generally TO packaging, and the structure of the laser is high, so that certain flat specific requirements cannot be met; and the laser packaged like an LED patch meets the flat design, but the light emitting direction of the laser is parallel to the PCB, so that the requirement of vertical light emitting cannot be met, and the patch type laser is not convenient to replace as the conventional direct-insertion tube seat in later maintenance.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides a novel self-indicating patch packaging laser;

the invention also provides a packaging method of the self-indicating patch packaging laser.

Interpretation of terms:

1. the COS, referred to as chip on submount, is a laser packaged on a submount.

2. Nd is YVO4 crystal, which is neodymium-doped yttrium vanadate crystal;

3. KTP crystal is potassium titanyl phosphate crystal.

The technical scheme of the invention is as follows:

a self-indication surface-mounted semiconductor laser comprises a tube seat and a tube cap arranged on the tube seat, wherein a COS (chip operating system), a 45-degree right-angle semi-reflection table, a crystal and a 45-degree right-angle total reflection table are sequentially arranged on the tube seat along a light path in a space formed by the tube seat and the tube cap.

The 808nm laser tube core sends out laser after being electrified, the laser is shot on a 45-degree right-angle semi-reflecting platform after being shot, a part of laser is reflected, the light path changes 90-degree vertical tube seat and is shot, the other part of laser penetrates through the reflecting platform and is shot on a crystal, 532nm green laser is generated after passing through the crystal, the green laser is shot on a subsequent 45-degree right-angle total reflecting platform, the light path changes 90 degrees and is shot from the vertical tube seat, and then the same laser generates two lasers with different wavelengths.

The tube seat is provided with 2 45-degree reflecting modules, the first 45-degree reflecting module (45-degree right-angle semi-reflecting table) reflects 50% of laser to enable the light path to be changed by 90 degrees, the laser can be emitted out perpendicular to the tube seat and can also transmit 50% of laser, crystals are arranged on the light path, 808nm laser is pumped into 1064nm laser and then passes through a frequency doubling crystal to generate 532nm laser green laser, the light path is changed by 90 degrees after the green laser passes through the second 45-degree reflecting module (45-degree right-angle total reflecting table), and the laser is emitted perpendicular to the tube seat.

Preferably according to the present invention, the COS is parallel mounted on a stem. The vertical height of the whole laser is reduced, so that the structure becomes flat, and the application of flat spaces is met. The material used was silver glue. The tube seat is provided with a COS positioning groove, so that the COS can be accurately positioned when being pasted with a chip.

Preferably according to the present invention, the COS includes a heat sink and a die sintered on the heat sink, the die being flip-chip mounted on the heat sink. The heat emitted by the die can be dissipated more quickly. The solder for adhering the tube core of the laser is gold-tin solder, and has the characteristics of high strength, good oxidation resistance, excellent thermal fatigue resistance and creep deformation resistance, low melting point, good fluidity and the like.

According to a preferred embodiment of the invention, the heat sink is an insulating heat sink. The tube shell is not electrified, and the probability of electrostatic breakdown of the laser is reduced in subsequent application.

The tube seat is different from a common TO tube seat, the tube seat does not have a tube tongue of a conventional tube seat, the length of the laser in the vertical direction is shortened, the structure is flattened, and the tube seat can be suitable for application in a narrow space.

According to the invention, the crystal is Nd: YVO4 crystal or KTP crystal, and the crystal is fixed on the tube seat through optical ultraviolet glue. The curing is fast and convenient to operate.

According to the invention, the pipe cap is preferably provided with a coating window. The transmittance increase rate of the laser can be increased. The pipe cap is sealed in the nitrogen environment in the packaging process, so that the laser works in an oxygen-free environment, the oxidation of the laser is reduced, and meanwhile, the sealed space can be dustproof.

According to the invention, the 45-degree right-angle semi-reflecting table and the 45-degree right-angle total reflecting table are preferably made of transparent glass, and the transparent glass is plated with a total reflection film or a semi-transparent film according to different purposes.

According to the invention, the reflecting surfaces of the 45-degree right-angle semi-reflecting platform and the 45-degree right-angle total reflecting platform are preferably flat mirror surfaces or concave mirror surfaces. The light can be converged and the light path change can be realized, a lens behind the laser can be omitted, and the convergence or collimation of the light path can be directly realized.

The packaging method of the self-indication patch packaged laser comprises the following steps:

(1) assembling the sintered COS on a tube seat;

preferably, the sintered COS is fixed on the tube seat through silver colloid, and is cured after being baked for 50-70min at the temperature of 140-150 ℃.

Further preferably, the sintered COS is assembled in the COS positioning groove corresponding to the tube seat, and the optical equipment is aligned to the position to ensure the parallelism of the optical path.

Further preferably, in the step (1), the die is assembled on the heat sink through a die bonding device to form the COS, and the COS is subjected to alloy sintering.

(2) Bonding the positive electrode and the negative electrode of the tube core to the positive electrode tube leg and the negative electrode tube leg of the tube seat respectively by using gold wires;

(3) assembling the 45-degree right-angle semi-reflection table into a corresponding groove on the tube seat, and dispensing and fixing;

(4) assembling the crystal, lighting the laser, adjusting the crystal to enable the crystal to generate green light, and lighting the ultraviolet glue for irradiation and fixation.

(5) Assembling the 45-degree right-angle total reflection table into the corresponding groove on the tube seat, and dispensing and fixing.

(6) And packaging the laser with a pipe cap in a nitrogen-filled environment to obtain the laser-packaged pipe cap. The oxidation of the laser in the use process can be reduced, and the service life is prolonged.

The invention has the beneficial effects that:

1. the laser adopts a special tube seat design, removes a tube tongue of an original TO tube seat, directly pastes COS on the tube seat, reduces the overall vertical height of the laser, enables the structure TO be flat, and meets the application of flat spaces.

2. The invention can realize 90-degree change of the light path by adopting a 45-degree right-angle reflecting table, and can also adjust the transmittance of the 45-degree reflecting table through coating, so that the light path can be changed by 90 degrees and vertically emitted after the transmitted 808nm laser passes through a crystal and the green laser passes through another reflecting table.

3. After the focusing lens is added to the subsequent optical path of the laser, the light beam can be converged or collimated, and then the laser is directly applied; the converged laser can also be coupled into an optical fiber and further applied after being conducted through the optical fiber. Therefore, the work of the invisible light with the wavelength of 808nm can be judged by observing the green laser, and the human eyes can be prevented from being accidentally injured.

4. The 45-degree right-angle reflecting platform can be made into an inward concave mirror surface to realize the convergence of the light path, so that a converging lens in a subsequent light path can be omitted, the distance of the light path is further reduced, and the flattening and the miniaturization of subsequent application are facilitated.

5. The invention adopts the sealing cap in the nitrogen-filled environment, so that the laser tube core can work in the oxygen-free environment, and the service life of the laser is prolonged;

6. the window on the pipe cap adopts anti-reflection coating film corresponding to the wavelength of the laser, so that the emergence rate of the laser is improved.

Description of the drawings:

FIG. 1 is a schematic diagram of the overall appearance of a self-indicating surface-mounted semiconductor laser according to the present invention;

FIG. 2 is a schematic cross-sectional view of a self-indicating surface-mounted semiconductor laser according to the present invention;

FIG. 3 is a schematic structural diagram of a self-indicating surface-mounted semiconductor laser according to the present invention before capping;

FIG. 4 is a schematic view of a flat mirror reflector according to the present invention.

1. Tube seat, 2, tube cap, 3, coating film window, 4, 45 degree right angle semi-reflecting table, 5, tube core, 6, heat sink, 7, crystal, 8, 45 degree right angle total reflecting table.

Detailed Description

The present invention will be further described by way of examples, but not limited thereto, with reference to the accompanying drawings.

Example 1

A self-indicating surface-mounted semiconductor laser comprises a tube seat 1 and a tube cap 2 arranged on the tube seat 1, and the overall appearance schematic diagram is shown in figure 1. In a space formed by the tube seat 1 and the tube cap 2, a COS (chip on chip), a 45-degree right-angle semi-reflecting platform 4, a crystal 7 and a 45-degree right-angle total reflecting platform 8 are sequentially arranged on the tube seat 1 along a light path; the cross-sectional view is schematically shown in fig. 2. The structure of the container before capping is schematically shown in fig. 3.

The 45-degree right-angle semi-reflecting platform 4 is characterized in that a reflecting surface is plated with a 808nm semi-permeable membrane, the transmittance and the reflectivity can be adjusted by adjusting a coating, 50% of 808nm laser emitted by the tube core 5 can be horizontally emitted through transmission, and 50% of light can be vertically emitted through changing a light path. A crystal 7 is arranged on a light path, 808nm laser is pumped into 1064nm laser and then passes through a frequency doubling crystal to generate 532nm laser green laser, the green laser passes through a 45-degree right-angle total reflection platform 8, the light path of the green laser is inverted by 90 degrees, and the green laser is emitted out of the vertical tube seat 1.

Example 2

A self-indicating die-mounted semiconductor laser as described in embodiment 1, except that the COS includes a heat sink 6 and a die 5 sintered on the heat sink 6, the die 5 being flip-chip mounted on the heat sink 6. The heat emitted by the die 5 can be dissipated more quickly. The solder for the laser to adhere to the tube core 5 is gold-tin solder, and has the characteristics of high strength, good oxidation resistance, excellent thermal fatigue resistance and creep property, low melting point, good fluidity and the like. The heat sink 6 is an insulating heat sink. The tube shell is not electrified, and the probability of electrostatic breakdown of the laser is reduced in subsequent application. COS is parallel mounted on the tube holder 1. The vertical height of the whole laser is reduced by about 2mm, so that the structure becomes flat, and the application of flat spaces is met. The material used was silver glue. The tube holder 1 is provided with a COS positioning groove, so that the COS can be accurately positioned during chip mounting.

Example 3

A self-indicating patch semiconductor laser according to

embodiment

1 or 2, differing in that,

the tube seat 1 is different from a common TO tube seat, the tube seat 1 does not have a tube tongue of a conventional tube seat, the length of the laser in the vertical direction is shortened, the structure is flattened, and the tube seat can be suitable for application in a narrow space.

The crystal 7 is Nd, YVO4 crystal or KTP crystal, and the crystal 7 is fixed on the tube seat 1 through optical ultraviolet glue. The curing is fast and convenient to operate.

The pipe cap 2 is provided with a coating film window 3. The transmittance increase rate of the laser can be increased. The pipe cap 2 is sealed in a nitrogen environment in the packaging process, so that the laser works in an oxygen-free environment, the oxidation of the laser is reduced, and meanwhile, the sealed space can be dustproof.

The 45-degree right-angle semi-reflecting table 4 and the 45-degree right-angle total reflecting table 8 are made of transparent glass, and the glass is plated with silver and gold according to different purposes, and the transparent glass is plated with a total reflection film or a semi-transparent film.

The reflecting surfaces of the 45-degree right-angle semi-reflecting table 4 and the 45-degree right-angle total reflecting table 8 are flat mirror surfaces. The flat mirror stage structure is shown in FIG. 4. The light emitted by the tube core 5 is changed by 90 degrees and finally exits vertical to the tube socket 1.

Example 4

A self-indicating patch semiconductor laser as described in embodiment 3, differing therefrom,

the reflecting surfaces of the 45-degree right-angle semi-reflecting table 4 and the 45-degree right-angle total reflecting table 8 are concave mirror surfaces. The concave surface can change the light emitted by the tube core 5 by 90 degrees, and can converge the light path to save subsequent lenses, reduce the vertical height by about 10mm, and enable the structure to be more flattened and miniaturized. And finally, the light is emitted out of the vertical tube seat 1.

Example 5

The packaging method of the self-indicating patch package laser of any one of embodiments 1 to 4, comprising the steps of:

(1) the die 5 is assembled to the heat sink 6 by means of a die 5 bonding apparatus to constitute COS, which is alloy sintered.

And (3) assembling the sintered COS into a corresponding positioning groove of the tube seat 1, aligning the position by using optical equipment to ensure that the optical path is parallel, arranging silver glue between the COS and the tube seat 1, and baking at the high temperature of 145 ℃ for 60min for curing.

(2) Bonding the positive electrode and the negative electrode of the tube core 5 to the positive electrode tube leg and the negative electrode tube leg of the tube seat 1 respectively by gold wires;

(3) assembling the 45-degree right-angle semi-reflecting table 4 into a corresponding groove on the tube seat 1, and dispensing and fixing;

(4) assembling the crystal 7, lighting the laser, adjusting the crystal 7 to enable the crystal 7 to generate green light, and lighting ultraviolet glue for irradiation and fixation.

(5) And assembling the 45-degree right-angle total reflection table 8 into a corresponding groove on the tube seat 1, and dispensing and fixing.

(6) And packaging the tube cap 2 on the laser in a nitrogen-filled environment to obtain the laser tube. The oxidation of the laser in the use process can be reduced, and the service life is prolonged.

Claims

1. A self-indication surface-mounted semiconductor laser is characterized by comprising a tube seat and a tube cap arranged on the tube seat, wherein a COS (chip operating system), a 45-degree right-angle semi-reflecting platform, a crystal and a 45-degree right-angle total reflecting platform are sequentially arranged on the tube seat along a light path in a space formed by the tube seat and the tube cap.

2. A self-indicating chip semiconductor laser as claimed in claim 1 wherein said COS is parallel chip on a stem.

3. A self-indicating die-mounted semiconductor laser as claimed in claim 1 wherein said COS comprises a heat sink and a die sintered on said heat sink, said die being flip-chip mounted on said heat sink.

4. A self-indicating patch semiconductor laser as claimed in claim 3 wherein said heat sink is an insulating heat sink.

5. The self-indicating patch semiconductor laser as claimed in claim 1, wherein the crystal is Nd: YVO4 crystal or KTP crystal, and the crystal is fixed on the stem by optical ultraviolet glue.

6. A self-indicating die-attach semiconductor laser as claimed in claim 1 wherein the cap has a coated window.

7. A self-indicating patch semiconductor laser as claimed in claim 1, wherein the 45 ° right-angle semi-reflecting stage and the 45 ° right-angle total reflecting stage are made of transparent glass, and the transparent glass is coated with a total reflection film or a semi-transparent film.

8. A self-indicating patch semiconductor laser as claimed in claim 1, wherein the reflecting surface of the 45 ° right-angle semi-reflecting stage and the 45 ° right-angle total reflecting stage is a flat mirror surface or a concave mirror surface.

9. A packaging method of the self-indicating patch package laser device according to any one of claims 1 to 8, comprising the steps of:

(1) assembling the sintered COS on a tube seat;

(3) assembling the 45-degree right-angle semi-reflection table on a tube seat, and dispensing and fixing;

(4) assembling a crystal, lightening a laser, adjusting the crystal to enable the crystal to generate green light, and lighting ultraviolet glue for irradiation and fixation;

(5) assembling a 45-degree right-angle total reflection table on a tube seat, and dispensing and fixing;

(6) packaging a pipe cap on the laser in a nitrogen-filled environment to obtain the laser;

preferably, in the step (1), the sintered COS is fixed on a tube seat through silver colloid, and is cured after being baked for 50-70min at the temperature of 140-150 ℃;

preferably, in the step (1), the sintered COS is assembled in the COS positioning groove corresponding to the stem, and the optical device is aligned to ensure that the optical path is parallel.

10. The packaging method of the self-indicating patch package laser as claimed in claim 9, wherein the step (1) is to assemble the die on the heat sink by a die bonding apparatus to form the COS, and the COS is alloy sintered.