阅读说明：本技术 一种泵浦激光器封装结构及封装方法 (Pump laser packaging structure and packaging method ) 是由 付传尚 开北超 孙素娟 徐现刚 郑兆河 于 2019-10-30 设计创作，主要内容包括：本发明涉及一种泵浦激光器封装结构及封装方法,属于半导体激光器叠阵封装技术领域。封装结构包括mini巴条、钨铜热沉、AlN陶瓷片、散热热沉和电极,mini巴条和钨铜热沉焊接组成巴条阵列,巴条阵列通过AlN陶瓷片焊接在散热热沉上,电极通过电极绝缘片封装到散热热沉两端。本发明封装的泵浦激光器发光面积与晶体端面相匹配,发出的光能够完全进入所要泵浦的晶体棒中,解决了多余的光照射在晶体侧面或者其他位置导致的产热问题。(The invention relates to a packaging structure and a packaging method of a pump laser, and belongs to the technical field of stack array packaging of semiconductor lasers. The packaging structure comprises a mini bar, a tungsten-copper heat sink, an AlN ceramic chip, a heat dissipation heat sink and electrodes, wherein the mini bar and the tungsten-copper heat sink are welded to form a bar array, the bar array is welded on the heat dissipation heat sink through the AlN ceramic chip, and the electrodes are packaged at two ends of the heat dissipation heat sink through electrode insulation sheets. The light emitting area of the pump laser packaged by the invention is matched with the end face of the crystal, the emitted light can completely enter the crystal rod to be pumped, and the problem of heat generation caused by the fact that redundant light irradiates on the side face of the crystal or other positions is solved.)

1. A pumping laser packaging structure is characterized by comprising a mini bar, a tungsten-copper heat sink, an AlN ceramic chip, a heat dissipation heat sink and electrodes, wherein the mini bar and the tungsten-copper heat sink are welded to form a bar array, the bar array is welded on the heat dissipation heat sink through the AlN ceramic chip, and the electrodes are packaged at two ends of the heat dissipation heat sink through electrode insulation sheets.

2. The packaging structure of claim 1, wherein the lens is mounted above the bar array, the lens is fixed by a pad strip, the pad strip is fixed on the upper end of the heat sink, the cross section of the pad strip is L-shaped, the number of the pad strips is two, the two pad strips are symmetrically arranged on two sides of the upper end of the heat sink, the upper surface of the pad strip is parallel to the upper surface of the tungsten-copper heat sink, and the lens is arranged between the two pad strips.

3. The pump laser package of claim 2, wherein the lens is an O-shaped cylindrical lens.

4. The packaging structure of claim 1, wherein the AlN ceramic wafer is provided with AlN ceramic wafer slots, the mini bars correspond to the AlN ceramic wafer slots, the AlN ceramic wafer slots have a slot width equal to the thickness of the mini bars, the surface and back of the AlN ceramic wafer are metallized, and the metallization component is nickel gold; the side surface of the AlN ceramic plate and the groove are not metallized, and the side surface of the AlN ceramic plate and the groove are non-metallized areas.

5. The packaging structure of claim 1, wherein a mounting hole is formed in the middle of the heat sink.

6. The packaging structure of claim 1, wherein electrode fixing holes are formed at two ends of the heat sink.

7. The pump laser package structure of claim 1, wherein the mini bars are soldered to the tungsten copper heat sink using high temperature solder, the AlN ceramic chip is soldered to the heat sink using high temperature solder, and the mini bar array and the AlN ceramic chip are soldered using low temperature solder;

preferably, the high temperature solder is AuSn solder and the low temperature solder is SnAg solder.

8. The pump laser package of claim 1, wherein the mini bars have a length of 3mm to 10mm, which is the same as the length of the tungsten copper heat sink.

9. The pump laser package of claim 1, wherein the tungsten copper heat sink has a thickness of 0.3mm to 1 mm.

10. A method for packaging the pump laser package structure of claim 2, the packaging steps are as follows:

determining the cleavage length of the mini bars according to the diameter of the pump crystal, packaging the cleaved mini bars into bar arrays through high-temperature solder, packaging the AlN ceramic plates on a heat dissipation heat sink through the high-temperature solder, welding the packaged bar arrays on the AlN ceramic plates through the low-temperature solder, packaging electrodes at two ends of the heat dissipation heat sink through electrode insulation sheets, finally installing lenses above the bar arrays, and carrying out optical treatment on the bars through the lenses to obtain pump light with concentrated energy and homogenized light spots.

Technical Field

The invention relates to a packaging structure and a packaging method of a pump laser, and belongs to the technical field of stack array packaging of semiconductor lasers.

Background

The conduction cooling semiconductor laser has the advantages of small volume, low price, high efficiency and long service life, and is mainly applied to the fields of industrial pumping, material processing, medical cosmetology, scientific research, military industry and the like. In the field of pumping applications, the focus is mainly on the Nd: for pumping of YAG, Nd, YVO4 and other crystals, the requirements on the packaging volume and the integration level of a laser are higher and higher for the application of end pumping of the crystals. The commonly used conduction cooling semiconductor laser in the market at present mainly adopts a centimeter bar for packaging, the size of the commonly used conduction cooling semiconductor laser is basically fixed to be 1cm in the period direction, in order to reduce the packaging volume and improve the packaging integration level, the packaging area is usually reduced by adopting a method of reducing the light emitting interval of the bar, but the laser formed by the centimeter bar cannot meet the requirements of certain fields on the laser volume, particularly for the application direction of pumping at the end face of a Nd: YAG crystal bar, the diameter of the end face of the crystal bar is usually less than 1cm, the light emitted by the laser formed by the 1cm bar cannot be completely absorbed, so that the waste of an optical energy source is caused, in addition, the redundant laser irradiates on the YAG crystal bar, so that the heat is generated, the conversion efficiency is lowered, the laser is burnt out and other adverse effects are.

Chinese patent document (publication number: CN104242048B) discloses a conduction cooling stacked-array semiconductor laser packaging structure, which comprises a laser chip set and an insulating heat sink, wherein the laser chip set adopts a plurality of laser chips to form a stacked-array module, and each laser chip is provided with a substrate; the method is characterized in that: the two end faces in the stacking direction of the stacked array module chips are welded with a positive connecting block and a negative connecting block in a fitting manner; two L-shaped conducting strips which are not in contact with each other are arranged on the surface of the insulating heat sink in a centrosymmetric manner and respectively serve as a leading-out positive electrode and a leading-out negative electrode; the bottoms of the positive connecting block and the negative connecting block are respectively and correspondingly welded and fixed on the long parts of the two L-shaped conducting strips, and the stacked array module corresponds to an area formed by the two L-shaped conducting strips on the surface of the insulating heat sink in an enclosing manner; the short parts of the two L-shaped conducting strips are provided with mounting holes. The invention does not solve the problem of the transverse size of the bar, the YAG crystal with a smaller end face still cannot meet the use requirement, and the excessive light leakage can cause the heat accumulation of the crystal bar and easily causes failure.

Chinese patent document (publication number: CN103457151A) discloses a high-temperature hard solder quasi-continuous semiconductor laser bar array packaging method, which utilizes a special tool clamp to stack n bars, n +1 conductive heat dissipation spacer blocks and n +1 electrically insulating radiating fins alternately by using high-temperature hard solder, and perform one-time reflow soldering to form a laser bar array unit, and then perform reflow soldering to form the laser bar array unit and a heat sink by using soft solder with relatively low temperature. The method can obviously reduce the welding stress when the high-temperature hard solder quasi-continuous semiconductor laser bar is packaged in a stacked array mode, and the service life, the yield and the photoelectric performance of the device are improved. The method packages a plurality of bars at one time, but does not optically process output light, and has relatively poor use effect on YAG crystals with small end faces.

In view of the above, it is necessary to develop a pump laser package structure that effectively solves the problems of incomplete light absorption and heat generation of residual light.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides a pump laser packaging structure which effectively solves the problems that light cannot be completely absorbed and residual light generates heat.

The invention also provides a packaging method of the pump laser packaging structure.

The technical scheme of the invention is as follows:

a pumping laser packaging structure comprises a mini bar, a tungsten-copper heat sink, an AlN ceramic plate, a heat dissipation heat sink and electrodes, wherein the mini bar and the tungsten-copper heat sink are welded to form a bar array, the bar array is welded on the heat dissipation heat sink through the AlN ceramic plate, and the electrodes are packaged at two ends of the heat dissipation heat sink through electrode insulation sheets.

Preferably, a lens is installed above the bar array, the lens is fixed through a gasket, and the gasket is fixed at the upper end of the heat dissipation heat sink.

Further preferably, the cross section of the filler strip is L-shaped, the number of the filler strips is two, the two filler strips are symmetrically arranged on two sides of the upper end of the heat dissipation heat sink, the upper surface of the filler strip is parallel to the upper surface of the tungsten copper heat sink, and a lens is arranged between the two filler strips.

Further preferably, the lens is an O-shaped cylindrical lens.

Preferably, the AlN ceramic plate slots are formed in the AlN ceramic plate, the mini bars correspond to the AlN ceramic plate slots, the slot width of the AlN ceramic plate slots is consistent with the thickness of the mini bars, and the packaging stress is reduced through the slots.

Preferably, the surface and the back of the AlN ceramic plate are subjected to metallization treatment, and the metallization component is nickel and gold; the side surface of the AlN ceramic plate and the groove are not metallized, and the side surface of the AlN ceramic plate and the groove are non-metallized areas.

Preferably, the middle position of the heat dissipation heat sink is provided with a mounting and fixing hole, and the whole device is fixed through the mounting and fixing hole.

Preferably, electrode fixing holes are formed in the positions of the two ends of the heat dissipation heat sink, and the electrodes at the two ends are fixed through the electrode fixing holes.

Preferably, the mini bar is welded on the tungsten copper heat sink by using high-temperature welding flux, the AlN ceramic plate is welded on the heat dissipation heat sink by using high-temperature welding flux, and the mini bar array and the AlN ceramic plate are welded by using low-temperature welding flux.

More preferably, the high-temperature solder is AuSn solder, and the low-temperature solder is SnAg solder.

Preferably, the length of the mini bar is 3mm-10mm, and the length is consistent with the length of the tungsten-copper heat sink.

Preferably, the thickness of the tungsten copper heat sink is 0.3mm-1 mm.

A packaging method of a pump laser packaging structure comprises the following packaging steps:

determining the cleavage length of the mini bars according to the diameter of the pump crystal, packaging the cleaved mini bars into bar arrays through high-temperature solder, packaging the AlN ceramic plates on a heat dissipation heat sink through the high-temperature solder, welding the packaged bar arrays on the AlN ceramic plates through the low-temperature solder, packaging electrodes at two ends of the heat dissipation heat sink through electrode insulation sheets, finally installing lenses above the bar arrays, and carrying out optical treatment on the bars through the lenses to obtain pump light with concentrated energy and homogenized light spots.

The invention has the beneficial effects that:

1. the light emitting area of the pump laser packaged by the invention is matched with the end face of the crystal, the emitted light can completely enter the crystal rod to be pumped, and the problem of heat generation caused by the fact that redundant light irradiates on the side face of the crystal or other positions is solved.

2. The lens is adopted to focus and homogenize the light spots, so that the energy distribution of the laser is more concentrated and uniform, the beam quality of the pump light is improved, and the pumping efficiency is improved.

3. The pump laser packaged by the invention can be fixed through the middle hole position, and the matching parts of the pump laser can be simplified.

4. The pump laser packaged by the invention adopts high-temperature hard solder in the packaging process, has high reliability, adopts grooved AlN ceramic plate for insulation, reduces the packaging stress and improves the reliability.

5. The pump laser packaged by the invention has smaller volume and mass, and can meet the application of industries with harsh requirements.

Drawings

Fig. 1 is a diagram of a package structure of the present invention.

FIG. 2 is a view of the structure of the bar array of the present invention.

Fig. 3 is a structure diagram of the packaging structure of the bar array and the AlN ceramic chip of the present invention.

FIG. 4 is a partial block diagram of the present invention before the lens is mounted.

Wherein: 1. mini bars; 2. tungsten copper heat sink; 3. a heat sink for dissipating heat; 4. an electrode; 5. an electrode insulating sheet; 6. a filler strip; 7. a lens; 8. mounting a fixing hole; 9. an electrode fixing hole; 10. AlN ceramic plates; 11. and (4) slotting the AlN ceramic plate.

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:

as shown in figures 1-4, a pumping laser packaging structure comprises a mini bar 1, a tungsten-copper heat sink 2, an AlN ceramic plate 10, a heat dissipation heat sink 3 and an electrode 4, wherein the mini bar 1 and the tungsten-copper heat sink 2 are welded to form a bar array, as shown in figure 2, the thickness of the tungsten-copper heat sink 2 is 0.3mm, the length of the mini bar 1 is 3mm, the length of the mini bar is consistent with that of the tungsten-copper heat sink, the bar array is welded on the heat dissipation heat sink 3 through the AlN ceramic plate 10, and the electrode 4 is packaged to two ends of the heat dissipation heat sink through an electrode insulation sheet 5. The length of the tungsten-copper heat sink 2 is consistent with that of the mini bars, in consideration of stress release and heat dissipation capacity, W90Cu with the thermal conductivity of 188W/(m × K) and the CTE of 6.5ppm/K is selected as a tungsten-copper heat sink material, the Coefficient of Thermal Expansion (CTE) is basically consistent with that of the bar material, and stress release in the AuSn packaging process is guaranteed.

The mini bar with the proper length is cut out according to the diameter of the end face of the YAG crystal to be pumped to be packaged, so that the light emitting area of the packaged pump laser is matched with the end face of the crystal, the emitted light can completely enter the crystal rod to be pumped, and the problem of heat generation caused by the fact that the redundant light irradiates the side face of the crystal or other positions is solved.

Example 2:

the structure of a pump laser packaging structure is as described in embodiment 1, except that the thickness of the tungsten-copper heat sink 2 is 10mm, and the length of the mini bar is 1 mm.

Example 3:

the utility model provides a pumping laser packaging structure, the structure is as embodiment 1, the difference lies in, bar array top installation lens 7, lens are fixed through filler strip 6, filler strip 6 is fixed in the heat sink 3 upper ends of dispelling the heat, the cross section of filler strip is the L type, filler strip quantity is two, two filler strip symmetries set up in the heat sink upper end both sides of dispelling the heat, filler strip upper surface and tungsten copper heat sink upper surface parallel, set up lens between two filler strips, O type columnar lens is chooseed for use to lens 7, can be used to the fast axle direction compression of bar, obtain the higher pump light of light beam quality, adopt lens 7 to focus on the light spot, the homogenization, make laser instrument energy distribution concentrate more, it is even, the light beam quality of pump light has been improved, improve pumping efficiency.

Example 4:

a pumping laser packaging structure is as in embodiment 1, the difference lies in, there are slots 11 of AlN ceramic plate on the AlN ceramic plate 10, mini bar 1 corresponds to slot 11 position of AlN ceramic plate, the slot width of the slot of AlN ceramic plate is unanimous with the thickness of mini bar, the slot interval of AlN ceramic plate is unanimous with tungsten copper heat sink thickness, reduce the packaging stress through the slot, raise the reliability, the AlN ceramic plate 10 is used in the insulation of negative pole of the bottom of mini bar, the size corresponds to bar array of the encapsulation, surface and back metallization of AlN ceramic plate, the metallization is nickel gold; the side surface of the AlN ceramic plate and the groove are not metallized, and the side surface of the AlN ceramic plate and the groove are non-metallized areas.

Example 5:

the structure of the pump laser packaging structure is as described in embodiment 1, and the difference is that an installation fixing hole 8 is formed in the middle of a heat dissipation heat sink 3, the whole device is fixed through the installation fixing hole 8, electrode fixing holes 9 are formed in the two ends of the heat dissipation heat sink 3, and electrodes at the two ends are fixed through the electrode fixing holes 9.

Example 6:

a pumping laser packaging structure is as in embodiment 1, the difference lies in that when mini bars are welded on a tungsten copper heat sink, high-temperature solder is used, when AlN ceramic plates are welded on a heat dissipation heat sink, high-temperature solder is used, the high-temperature solder is AuSn solder, and low-temperature solder is used for welding between the mini bar arrays and the AlN ceramic plates, and the low-temperature solder is SnAg solder.

Example 7:

a method for packaging the pump laser package structure according to embodiment 3, the packaging steps are as follows:

determining the cleavage length of the mini bars according to the diameter of the pump crystal, packaging the cleaved mini bars into bar arrays through high-temperature solder, packaging the AlN ceramic plates on a heat dissipation heat sink through the high-temperature solder, welding the packaged bar arrays on the AlN ceramic plates through the low-temperature solder, packaging electrodes at two ends of the heat dissipation heat sink through electrode insulation sheets, finally installing lenses above the bar arrays, and carrying out optical treatment on the bars through the lenses to obtain pump light with concentrated energy and homogenized light spots.