CN106329308A

CN106329308A - Semiconductor laser encapsulation structure with low Smile

Info

Publication number: CN106329308A
Application number: CN201610946466.XA
Authority: CN
Inventors: 王卫锋; 陶春华; 梁雪杰; 刘兴胜
Original assignee: Focuslight Technologies Inc
Current assignee: Focuslight Technologies Inc
Priority date: 2016-10-26
Filing date: 2016-10-26
Publication date: 2017-01-11
Also published as: WO2018077078A1

Abstract

The invention discloses a semiconductor laser encapsulation structure with low Smile. Stress slow-release layers with longitudinal symmetry are applied to the structure in design, so that longitudinal corresponding strain shrinkage amounts in heat sinking are consistent, the minimum stress endured by a laser chip is ensured, and the smile effect of the semiconductor laser is effectively reduced.

Description

A kind of capsulation structure for semiconductor laser of low Smile

Technical field

The present invention is semiconductor laser encapsulation field, the encapsulation knot of the semiconductor laser of a kind of low Smile Structure.

Background technology

In semiconductor laser bar or folded battle array encapsulate, produce due to heat sink coupling with laser chip thermal coefficient of expansion Raw thermal stress, causes laser array to deform upon at vertical quick shaft direction.And laser array is at vertical direction luminescence chi Very little only about 1 μm, so less displacement produces considerable influence to luminescence, makes in array each luminescence unit not at same On straight line, cause luminous bending (being referred to as smile effect, also referred to as near field nonlinear effect), even can if thermal stress is excessive The weld layer between chip and metal heat sink is caused to ftracture, the problem such as semiconductor laser chip fracture, have a strong impact on quasiconductor The reliability of laser instrument and life-span.The thermal coefficient of expansion of such as chip is 6.7ppm/K, heat sink selection metallic copper, the heat of metallic copper Coefficient of expansion 17.8ppm/K, same length chip and copper, often change 1 DEG C, the length change of copper will be 2.7 times of chip.

Method for reduction semiconductor laser smile effect is to increase heat between laser chip and copper are heat sink at present The stress slow release layer that the coefficient of expansion is close with laser chip, reduces the smile effect of semiconductor laser, but along with quasiconductor Range of application that laser instrument is constantly expanded and the raising requiring beam quality, the suppression to smile effect has had higher Requirement so that prior art is difficult to meet new application demand.

Summary of the invention

In order to solve the deficiencies in the prior art, the present invention proposes the capsulation structure for semiconductor laser of a kind of low Smile.

Technical scheme is as follows:

The capsulation structure for semiconductor laser of a kind of low Smile, two faces of described heat sink mutual correspondence are respectively arranged with heat The stress slow release layer that the coefficient of expansion mates with laser chip, laser chip is bonded to aforesaid stress slow release layer on one of them. The stress slow release layer in two faces of described heat sink mutual correspondence is symmetrical structure, and stress slow release layer is overlying on part heat sink surface, or Person covers heat sink whole surface.

The thermal coefficient of expansion span of described stress slow release layer is 5 ~ 10ppm/K.

Described stress slow release layer is specially copper tungsten or graphite copper or graphitized alumina or Graphene or copper gold Hard rock, or ceramic copper-clad structure, or pottery plated copper structure etc..

Described stress slow release layer can be structure as a whole with heat sink.

The metal heat sinks such as described heat sink specially copper.

The principle of the present invention be the upper and lower two-layer of heat sink employing symmetrical with laser chip CTE(thermal coefficient of expansion) mate should Power slow release layer, though the stress slow release layer not in direct contact laser chip of lower floor, but such that heat sink strain up and down During contraction, amount of contraction is suitable so that the strain on laser chip is less, thus realizes relatively low smile effect.

The invention have the advantages that

The capsulation structure for semiconductor laser of low Smile proposed by the invention, the design of laterally zygomorphic stress slow release layer makes The most corresponding strain amount of contraction is consistent, it is ensured that the stress that laser chip is born is minimum, effectively reduces smile effect.This Outward, the stress slow release layer of the present invention can be integrally formed structure with heat sink, and such as copper is integrated with DBC structure, and decreasing should Power slow release layer is bonded to heat sink packaging process, it is to avoid this step operation producible technique is bad, improves the reliable of device Property.

Accompanying drawing explanation

Fig. 1 is embodiments of the invention one.

Fig. 2 is embodiments of the invention two.

Fig. 3 a is the simle test value of the semiconductor laser using traditional one side stress slow release layer.

Fig. 3 b is the smile test value of the semiconductor laser of the stress slow release layer using double-sided symmetrical structure of the present invention.

Drawing reference numeral illustrates: 1-is heat sink, 2-laser chip, 3-stress slow release layer.

Detailed description of the invention

Fig. 1 is one embodiment of the present of invention, and the capsulation structure for semiconductor laser of a kind of low Smile includes heat sink 1 He Laser chip 2；It is respectively arranged with, on described heat sink 1 two the most corresponding faces, the stress that thermal coefficient of expansion mates with laser chip Slow release layer 3, laser chip is bonded to aforesaid stress slow release layer 3 on one of them.

Between described 2 stress slow release layers on heat sink corresponding two faces symmetrically, stress slow release layer can be only Covering part heat sink surface (ensures the bonding face more than laser chip), it is also possible to cover heat sink full surface, this side Formula is with reference to the embodiment two in Fig. 2.During symmetrical structure can make the strain of heat sink upper and lower surface shrink, amount of contraction is consistent.

In order to mate the thermal coefficient of expansion of laser chip, the thermal coefficient of expansion span of described stress slow release layer is 5 ~ 10ppm/K.Described stress slow release layer is specifically as follows the composites such as copper tungsten, graphite copper, graphitized alumina, Graphene, copper diamond, Or ceramic copper-clad structure, or pottery plated copper structure.

Above-mentioned stress slow release layer 3 can also be integrated with heat sink 1, is specially and realizes stress slow release layer in technique 3 are processed as one with heat sink, simplify the packaging technology flow process of follow-up semiconductor laser.Structurally it is specially copper heat sink Integrated with DBC structure, or copper is heat sink integrated with DPC structure.

Identical laser chip is encapsulated into respectively semiconductor laser and the present invention of traditional one side stress slow release layer The stress slow release layer of double-sided symmetrical structure, respectively above-mentioned two semiconductor laser is carried out smile test, obtain Fig. 3 a and The test result of Fig. 3 b, Fig. 3 a is to use the semiconductor laser of traditional one side stress slow release layer to carry out Smile value to survey Examination, the width indicated such as Z axis in figure, its smile test value is that 10.68um, Fig. 3 b is for using double-sided symmetrical structure of the present invention The smile test value of semiconductor laser of stress slow release layer be 0.855um.Therefore present invention reduces semiconductor laser Smile effect, optimize beam quality and the performance of semiconductor laser.

Claims

1. the capsulation structure for semiconductor laser of a low Smile, it is characterised in that: include heat sink and laser chip；Described heat It is respectively arranged with the stress slow release layer that thermal coefficient of expansion mates, laser chip key with laser chip on heavy two the most corresponding faces Together in aforesaid stress slow release layer on one of them.

The capsulation structure for semiconductor laser of a kind of low Smile the most according to claim 1, it is characterised in that: described should The thermal coefficient of expansion span of power slow release layer is 5 ~ 10ppm/K.

The capsulation structure for semiconductor laser of a kind of low Smile the most according to claim 2, it is characterised in that: described Stress slow release layer is copper tungsten or graphite copper or graphitized alumina or Graphene or copper diamond, or ceramic copper-clad knot Structure, or pottery plated copper structure.

The capsulation structure for semiconductor laser of a kind of low Smile the most according to claim 1, it is characterised in that: described heat The stress slow release layer in heavy two the most corresponding faces is symmetrical structure.

The capsulation structure for semiconductor laser of a kind of low Smile the most according to claim 4, it is characterised in that: described should Power slow release layer is overlying on part heat sink surface, or covers heat sink whole surface.

The capsulation structure for semiconductor laser of a kind of low Smile the most according to claim 1, it is characterised in that: described Stress slow release layer is structure as a whole with heat sink.