CN103811991A - Method of improving cooling effect of semiconductor laser chip - Google Patents
Method of improving cooling effect of semiconductor laser chip Download PDFInfo
- Publication number
- CN103811991A CN103811991A CN201410049513.1A CN201410049513A CN103811991A CN 103811991 A CN103811991 A CN 103811991A CN 201410049513 A CN201410049513 A CN 201410049513A CN 103811991 A CN103811991 A CN 103811991A
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- semiconductor laser
- laser chip
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- radiating efficiency
- conversion layer
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- 238000000034 method Methods 0.000 title claims abstract description 36
- 239000004065 semiconductor Substances 0.000 title claims abstract description 29
- 238000001816 cooling Methods 0.000 title abstract 3
- 230000000694 effects Effects 0.000 title abstract 2
- 239000007788 liquid Substances 0.000 claims abstract description 26
- 238000006243 chemical reaction Methods 0.000 claims abstract description 23
- 239000000758 substrate Substances 0.000 claims abstract description 17
- 238000000137 annealing Methods 0.000 claims abstract description 16
- 238000005530 etching Methods 0.000 claims abstract description 16
- 238000001704 evaporation Methods 0.000 claims abstract description 13
- 238000004381 surface treatment Methods 0.000 claims abstract description 11
- 238000001259 photo etching Methods 0.000 claims abstract description 7
- 238000005498 polishing Methods 0.000 claims description 18
- 238000004140 cleaning Methods 0.000 claims description 16
- 230000008020 evaporation Effects 0.000 claims description 11
- 239000010949 copper Substances 0.000 claims description 9
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 8
- 229910001218 Gallium arsenide Inorganic materials 0.000 claims description 8
- 229910052802 copper Inorganic materials 0.000 claims description 8
- 238000001514 detection method Methods 0.000 claims description 5
- 238000001312 dry etching Methods 0.000 claims description 4
- 238000007747 plating Methods 0.000 claims description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 4
- 239000000126 substance Substances 0.000 claims description 3
- 238000001039 wet etching Methods 0.000 claims description 3
- 230000007797 corrosion Effects 0.000 claims description 2
- 238000005260 corrosion Methods 0.000 claims description 2
- ITSIDSVWDOBMFV-UHFFFAOYSA-N [Ni].[Ge].[Cu] Chemical compound [Ni].[Ge].[Cu] ITSIDSVWDOBMFV-UHFFFAOYSA-N 0.000 abstract 1
- FKNWMNQVNAGIDF-UHFFFAOYSA-N copper platinum titanium Chemical compound [Ti][Cu][Pt] FKNWMNQVNAGIDF-UHFFFAOYSA-N 0.000 abstract 1
- 230000003287 optical effect Effects 0.000 abstract 1
- 238000004519 manufacturing process Methods 0.000 description 5
- 239000000463 material Substances 0.000 description 5
- 238000010586 diagram Methods 0.000 description 4
- GPXJNWSHGFTCBW-UHFFFAOYSA-N Indium phosphide Chemical compound [In]#P GPXJNWSHGFTCBW-UHFFFAOYSA-N 0.000 description 3
- 230000005855 radiation Effects 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 2
- 238000002360 preparation method Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 238000003776 cleavage reaction Methods 0.000 description 1
- 239000007769 metal material Substances 0.000 description 1
- 238000002488 metal-organic chemical vapour deposition Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 238000012536 packaging technology Methods 0.000 description 1
- 230000002787 reinforcement Effects 0.000 description 1
- 230000007017 scission Effects 0.000 description 1
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- Semiconductor Lasers (AREA)
Abstract
The invention provides a method of improving the cooling effect of a semiconductor laser chip. The method comprises the following steps: a) epitaxially growing a preset conversion layer, an N-zone epitaxial layer, an active area and a P-zone epitaxial layer on a growing substrate sequentially; b) preparing a P-surface electrode on the P-zone epitaxial layer by photoetching, etching, evaporating TiPtAu (Titanium-Platinum-Copper) and annealing; c) immersing the P-surface electrode into corrosive liquid, and using the corrosive liquid to corrode the preset conversion layer; and d) after the N-zone epitaxial layer obtained in the step c) is subjected to the surface treatment step, evaporating AuGeNi (Copper-Germanium-Nickel) to obtain an N-surface electrode. The semiconductor laser chip with large power provided by the invention can perform double-faced cooling, so that thermal resistance can be greatly reduced; and the optical power output of devices can be improved to a large extent, so that the semiconductor laser chip has significant technical advancement and good economic benefit.
Description
Technical field
The present invention relates to laser field, refer to especially a kind of method that improves semiconductor laser chip radiating efficiency.
Background technology
The preparation process of existing semiconductor laser chip is: 1) adopt GaAs or the InP substrate base material (being growth substrates) as chip growth, the meticulous chip that is several microns by the method such as MOCVD or MBE epitaxial growth gross thickness in growth substrates, forms laser epitaxial wafer; 2) obtain electrode structure at right side at the positive process meanses such as evaporation, sputter, photoetching that adopt of epitaxial wafer; 3) adopt lapping mode by behind substrate thinning to 100 micron left and right, preparation backplate material; 4) by drawing sliver mode, form light output end with the natural cleavage plane of semi-conducting material, and on the light output end of front and back, plate respectively anti-reflection film and increase anti-film, to plate anti-reflection film end face as light output end; 5) obtain discrete semiconductor chip of laser by drawing sliver mode.
There are the following problems for above-mentioned technology: semiconductor laser chip generally only has several micron thickness, and in chip, the overwhelming majority is remaining backing material, and the thermal conductivity far of GaAs or indium phosphide is lower than metal material.Be inverted technique reinforcement heat radiation although be widely used in existing semiconductor laser packaging technology, the heat producing when laser works is difficult to shed by backing material.
Summary of the invention
The present invention proposes a kind of method that improves semiconductor laser chip radiating efficiency, has solved the poor problem of chip of laser radiating efficiency in prior art.
Technical scheme of the present invention is achieved in that a kind of method that improves semiconductor laser chip radiating efficiency, comprises the steps: a) the growth substrates preset conversion layer of epitaxial growth, N district epitaxial loayer, active area and P district epitaxial loayer successively; B) make p side electrode through photoetching, etching, evaporation TiPtAu and annealing operation at described P district epitaxial loayer; C) described step b) gained is immersed to corrosive liquid, utilize the described preset conversion layer of described corrosive liquid corrosion; D) after the described N district of described step c) gained epitaxial loayer process surface treatment step, evaporation AuGeNi makes N face electrode.
Further, described p side electrode and described N face electrode form respectively P face radiator structure and N face radiator structure.
Preferably, described N face radiator structure and described P face radiator structure are specially copper layer, and described copper layer forms by plating mode.
Preferably, described P district epitaxial loayer comprises current confinement structure, and described current confinement structure is specially ridge structure.
Further, described preset conversion layer can be corroded liquid selectivity eliminate; Described corrosive liquid is specially HF or BOE.
Further, described growth substrates comprises GaAs.
Further, described preset conversion layer comprises AlAs.
Preferably, described annealing is carried out in 400 ℃～470 ℃ temperature ranges; The time range of described annealing is 30s～60s.
Preferably, described etching is specially dry etching or wet etching, with optionally and/or anisotropic etching method carry out; Described surface treatment step comprises at the most polishing step, detecting step and is positioned at the cleaning step before or after described polishing step, and described polishing step is specially chemical polishing or mechanical polishing; Described cleaning step is specially described corrosive liquid cleaning or water cleans; Described detecting step is specially smoothness detection and surface cleanness detects.
Beneficial effect of the present invention is:
1) the high power laser chip double-side heat radiation that the present invention forms, thermal resistance declines to a great extent, and largely improves the luminous power output of device;
2) in semiconductor laser chip manufacture method process of the present invention, growth substrates can reuse, and reduces production costs.
Accompanying drawing explanation
In order to be illustrated more clearly in the embodiment of the present invention or technical scheme of the prior art, to the accompanying drawing of required use in embodiment or description of the Prior Art be briefly described below, apparently, accompanying drawing in the following describes is only some embodiments of the present invention, for those of ordinary skills, do not paying under the prerequisite of creative work, can also obtain according to these accompanying drawings other accompanying drawing.
Fig. 1 is the flow chart of an a kind of embodiment of method who improves semiconductor laser chip radiating efficiency of the present invention;
Fig. 2 is step a) resulting structures schematic diagram of the present invention;
Fig. 3 is step b) resulting structures schematic diagram of the present invention;
Fig. 4 is step c) resulting structures schematic diagram of the present invention;
Fig. 5 is step d) resulting structures schematic diagram of the present invention.
In figure:
1, growth substrates; 2, N district epitaxial loayer; 3, active layer; 4, P district epitaxial loayer; 5, preset conversion layer; 6, p side electrode; 7, P face radiator structure; 8, N face electrode; 9, N face radiator structure.
Embodiment
Below in conjunction with the accompanying drawing in the embodiment of the present invention, the technical scheme in the embodiment of the present invention is clearly and completely described, obviously, described embodiment is only the present invention's part embodiment, rather than whole embodiment.Based on the embodiment in the present invention, those of ordinary skills, not making the every other embodiment obtaining under creative work prerequisite, belong to the scope of protection of the invention.
Embodiment 1
As shown in Fig. 1～5, the manufacture method of a kind of semiconductor laser chip of the present invention, comprises the steps:
A) the growth substrates 1 preset conversion layer 5 of epitaxial growth, N district epitaxial loayer 2, active area 3 and P district epitaxial loayer 4 successively;
B) make p side electrode 6 through photoetching, etching, evaporation TiPtAu and annealing at P district epitaxial loayer 4;
C) step b) gained is immersed to corrosive liquid, utilize corrosive liquid to corrode preset conversion layer 5;
D) after the N district of step c) gained epitaxial loayer 2 process surface treatment step, evaporation AuGeNi prepares N face electrode 8.
P district epitaxial loayer 4 comprises current confinement structure.
Preset conversion layer 5 can be corroded liquid selectivity eliminate; Corrosive liquid is specially BOE.
Growth substrates 1 comprises GaAs.Preset conversion layer 5 comprises AlAs.
Perform step and b) first carry out before cleaning operation.
Annealing is carried out at 470 ℃ of temperature; Annealing time is 30s.
Etching is specially wet etching, carries out by anisotropic etching method; Surface treatment step comprises polishing step, detecting step and is positioned at the cleaning step after polishing step, and polishing step is specially mechanical polishing; Cleaning step is specially water and cleans; Detecting step is specially smoothness detection and surface cleanness detects.Embodiment 2
As shown in Fig. 1～5, the manufacture method of a kind of semiconductor laser chip of the present invention, comprises the steps:
A) the growth substrates 1 preset conversion layer 5 of epitaxial growth, N district epitaxial loayer 2, active area 3 and P district epitaxial loayer 4 successively;
B) make p side electrode 6 through photoetching, etching, evaporation TiPtAu and annealing at P district epitaxial loayer 4;
C) step b) gained is immersed to corrosive liquid, utilize corrosive liquid to corrode preset conversion layer 5;
D) after the N district of step c) gained epitaxial loayer 2 process surface treatment step, evaporation AuGeNi prepares N face electrode 8.
N face radiator structure 9 and P face radiator structure 7 are specially copper layer, and copper layer forms by plating mode.
P district epitaxial loayer 4 comprises current confinement structure, and current confinement structure is specially ridge structure.
Preset conversion layer 5 can be corroded liquid selectivity eliminate; Corrosive liquid is specially HF.
Growth substrates 1 comprises GaAs.Preset conversion layer 5 comprises AlAs.
Perform step and b) first carry out before cleaning operation.
Annealing is carried out at 400 ℃ of temperature; Annealing time is 60s.
Etching is specially dry etching, carries out by etching method optionally; Surface treatment step comprises polishing step, detecting step and is positioned at the cleaning step before polishing step, and polishing step is specially chemical polishing; Cleaning step is specially corrosive liquid and cleans; Detecting step is specially smoothness detection and surface cleanness detects.
As shown in Fig. 1～5, the manufacture method of a kind of semiconductor laser chip of the present invention, comprises the steps:
A) the growth substrates 1 preset conversion layer 5 of epitaxial growth, N district epitaxial loayer 2, active area 3 and P district epitaxial loayer 4 successively;
B) make p side electrode 6 through photoetching, etching, evaporation TiPtAu and annealing at P district epitaxial loayer 4;
C) step b) gained is immersed to corrosive liquid, utilize corrosive liquid to corrode preset conversion layer 5;
D) after the N district of step c) gained epitaxial loayer 2 process surface treatment step, evaporation AuGeNi prepares N face electrode 8.
N face radiator structure 9 and P face radiator structure 7 are specially copper layer, and copper layer forms by plating mode.
P district epitaxial loayer 4 comprises current confinement structure, and current confinement structure is specially ridge structure.
Preset conversion layer 5 can be corroded liquid selectivity eliminate; Corrosive liquid is specially HF.
Growth substrates 1 comprises GaAs.Preset conversion layer 5 comprises AlAs.
Perform step and b) first carry out before cleaning operation.
Annealing is carried out at 440 ℃ of temperature; Annealing time is 45s.
Etching is specially dry etching, with optionally carrying out with anisotropic etching method; Surface treatment step comprises detecting step and cleaning step; Cleaning step is specially corrosive liquid cleaning or water cleans; Detecting step is specially smoothness detection and surface cleanness detects.
In the present invention, P face radiator structure 7 and N face radiator structure 9 can reach certain thickness, concrete thickness is ten microns to tens microns, from material application, employing conductive coefficient is the Cu of 401W/ (mK), be 0.55W/ (cmK) with respect to GaAs(conductive coefficient) and InP(conductive coefficient be 0.68W/ (cmK)) the capacity of heat transmission improve, realize two-side radiation from structural design simultaneously, thermal resistance declines to a great extent, largely improve the luminous power output of device, thereby improve the radiating efficiency of semiconductor laser chip, avoided causing the process of lapping of mechanical damage simultaneously, and then improve the reliability of semiconductor laser.
The foregoing is only preferred embodiment of the present invention, in order to limit the present invention, within the spirit and principles in the present invention not all, any modification of doing, be equal to replacement, improvement etc., within all should being included in protection scope of the present invention.
Claims (9)
1. a method that improves semiconductor laser chip radiating efficiency, is characterized in that, comprises the steps:
A) the growth substrates preset conversion layer of epitaxial growth, N district epitaxial loayer, active area and P district epitaxial loayer successively;
B) make p side electrode through photoetching, etching, evaporation TiPtAu and annealing at described P district epitaxial loayer;
C) described step b) gained is immersed to corrosive liquid, utilize the described preset conversion layer of described corrosive liquid corrosion;
D) after the described N district of described step c) gained epitaxial loayer process surface treatment step, evaporation AuGeNi makes N face electrode.
2. a kind of method that improves semiconductor laser chip radiating efficiency according to claim 1, is characterized in that, described p side electrode and described N face electrode form respectively P face radiator structure and N face radiator structure.
3. a kind of method that improves semiconductor laser chip radiating efficiency according to claim 2, is characterized in that, described N face radiator structure and described P face radiator structure are specially copper layer, and described copper layer forms by plating mode.
4. a kind of method that improves semiconductor laser chip radiating efficiency according to claim 1, is characterized in that, described P district epitaxial loayer comprises current confinement structure, and described current confinement structure is specially ridge structure.
5. a kind of method that improves semiconductor laser chip radiating efficiency according to claim 1, is characterized in that, described preset conversion layer can be corroded liquid selectivity eliminate; Described corrosive liquid is specially HF or BOE.
6. according to a kind of method that improves semiconductor laser chip radiating efficiency described in claim 1～5 any one, it is characterized in that, described growth substrates comprises GaAs.
7. a kind of method that improves semiconductor laser chip radiating efficiency according to claim 6, is characterized in that, described preset conversion layer comprises AlAs.
8. a kind of method that improves semiconductor laser chip radiating efficiency according to claim 7, is characterized in that, described annealing is carried out in 400 ℃～470 ℃ temperature ranges; The time range of described annealing is 30s～60s.
9. a kind of method that improves semiconductor laser chip radiating efficiency according to claim 8, is characterized in that, described etching is specially dry etching or wet etching, with optionally and/or anisotropic etching method carry out; Described surface treatment step comprises at the most polishing step, detecting step and is positioned at the cleaning step before or after described polishing step, and described polishing step is specially chemical polishing or mechanical polishing; Described cleaning step is specially described corrosive liquid cleaning or water cleans; Described detecting step is specially smoothness detection and surface cleanness detects.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410049513.1A CN103811991B (en) | 2014-02-13 | 2014-02-13 | Method of improving cooling effect of semiconductor laser chip |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410049513.1A CN103811991B (en) | 2014-02-13 | 2014-02-13 | Method of improving cooling effect of semiconductor laser chip |
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| CN103811991A true CN103811991A (en) | 2014-05-21 |
| CN103811991B CN103811991B (en) | 2017-05-24 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111048990A (en) * | 2019-12-26 | 2020-04-21 | 常州纵慧芯光半导体科技有限公司 | Laser chip and preparation method thereof |
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| CN1614792A (en) * | 2003-11-06 | 2005-05-11 | 厦门三安电子有限公司 | Semiconductor device and its preparing method |
| EP1879274A1 (en) * | 2006-07-14 | 2008-01-16 | Seiko Epson Corporation | Optical device and its manufacturing method, and optical device wafer |
| CN102064465A (en) * | 2010-12-16 | 2011-05-18 | 刘兴胜 | Bidirectional refrigeration type semiconductor laser and manufacturing method thereof |
| JP2012033975A (en) * | 2011-11-14 | 2012-02-16 | Nippon Telegr & Teleph Corp <Ntt> | Method of manufacturing semiconductor laser |
| CN102842850A (en) * | 2012-07-20 | 2012-12-26 | 沈光地 | Efficient high-power semiconductor laser device capable of radiating heat from double surfaces |
| CN102882124A (en) * | 2012-10-11 | 2013-01-16 | 长春理工大学 | Semiconductor laser chip structure suitable for being welded reversely |
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2014
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Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1614792A (en) * | 2003-11-06 | 2005-05-11 | 厦门三安电子有限公司 | Semiconductor device and its preparing method |
| EP1879274A1 (en) * | 2006-07-14 | 2008-01-16 | Seiko Epson Corporation | Optical device and its manufacturing method, and optical device wafer |
| CN102064465A (en) * | 2010-12-16 | 2011-05-18 | 刘兴胜 | Bidirectional refrigeration type semiconductor laser and manufacturing method thereof |
| JP2012033975A (en) * | 2011-11-14 | 2012-02-16 | Nippon Telegr & Teleph Corp <Ntt> | Method of manufacturing semiconductor laser |
| CN102842850A (en) * | 2012-07-20 | 2012-12-26 | 沈光地 | Efficient high-power semiconductor laser device capable of radiating heat from double surfaces |
| CN102882124A (en) * | 2012-10-11 | 2013-01-16 | 长春理工大学 | Semiconductor laser chip structure suitable for being welded reversely |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111048990A (en) * | 2019-12-26 | 2020-04-21 | 常州纵慧芯光半导体科技有限公司 | Laser chip and preparation method thereof |
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