CN101546799A - Preparation method of nitride LED with vertical structure - Google Patents
Preparation method of nitride LED with vertical structure Download PDFInfo
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- CN101546799A CN101546799A CN200810102801A CN200810102801A CN101546799A CN 101546799 A CN101546799 A CN 101546799A CN 200810102801 A CN200810102801 A CN 200810102801A CN 200810102801 A CN200810102801 A CN 200810102801A CN 101546799 A CN101546799 A CN 101546799A
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Abstract
The invention relates to a preparation method of a nitride LED with a vertical structure. The method comprises the following steps: a substrate where the nitride grows is taken; an auxiliary stripping layer grows on the substrate, and the stripping layer enables the linkage between the substrate and the subsequent epitaxy material to be relatively poorer; a nitride nucleation layer grows on the auxiliary stripping layer by an MOCVD method to ensure the high quality of the nitride; a layer of gallium nitride heavy layer material grows on the nitride nucleation layer; a multi-quantum-well LED structure layer grows on the gallium nitride heavy layer material by the MOCVD method to form a luminescent layer of the nitride LED, and the preparation of the p type nitride can be realized through HVPE; the substrate, the auxiliary stripping layer and the partial nitride nucleation layer are stripped to obtain an epitaxial wafer of the nitride LED with the vertical structure; an upper electrode is manufactured on the multi-quantum-well LED structure layer; and a lower electrode is manufactured under the nitride nucleation layer connected with the epitaxy[epitaxial] layer to finish the preparation of the nitride LED with the vertical structure.
Description
Technical field
The invention belongs to technical field of semiconductors, refer in particular to a kind of growing method that designs for the growth that realizes gallium nitride-based vertical structure LED epitaxial material, can realize in conjunction with MOCVD and HVPE and by peeling off certainly of nitride.
Background technology
The spectrum of nitride polynary system material is from 0.7ev to 6.2ev, it is luminous to be used for interband, color covers from infrared to ultraviolet wavelength, aspect optoelectronic applications, has great application prospect as blue light, green glow, ultraviolet light-emitting diodes (LED), short wavelength laser diode aspects such as (LD).Nitride LED is widely used in display, illumination, indicator light, billboard, traffic lights etc., and the light compositing light source is quickened in conduct in agricultural, the instrument of conduct diagnosis and treatment in medical treatment; Nitride royal purple light LD is just becoming the core components and parts of the Blue Ray of commander's DVD memory technology of future generation, has vast market prospect.Particularly people are more and more higher for the expection that light-emitting diode is applied to general illumination in recent years, make that the development of nitride based LED is swift and violent day by day.But will really realize the general illumination of nitride based LED or be called semiconductor lighting, also must improve the performance of nitride LED in the production cost that significantly reduces nitride LED, mainly be aspects such as luminous efficiency, heat dispersion and life-span.
People generally acknowledge that the nitride LED of vertical stratification can have extraordinary current expansion performance and heat dispersion at present, thereby may realize higher luminous efficiency and longer life-span.The method of existing realization nitride vertical stratification LED mainly contains four kinds: first kind is to use the Sapphire Substrate heteroepitaxy the most extensive, that performance is best, because the non-conductive LED that needs the removal sapphire can make vertical stratification of Sapphire Substrate, more common way is to remove substrate by laser lift-off after heteroepitaxy now, subject matter is that laser lift-off equipment is relatively more expensive, the while stripping technology is more complicated also, need to realize the transfer of nitride film, exist the not high problem of rate of finished products by bonding technology at least once; Second kind is to remove substrate by the mode of mechanical lapping after the heteroepitaxy on the substrates such as sapphire or SiC, and the problem of this method is substrate, and often hardness is bigger, grinds time-consuming taking a lot of work, and cost is higher; The third method is exactly a direct extension nitride material on conductive substrates, and such as the substrates such as Si of metal substrate or low-resistance, its problem is that epitaxial crystal is of poor quality, does not still have very ripe technological development; The 4th kind just is to use sacrifice layer, realize peeling off of substrate by removing sacrifice layer, this method need be transferred to nitride material other support substrates equally and get on, and the sacrifice layer of laterally removing between substrate and the epitaxial loayer also greatly reduces the time efficiency and the rate of finished products of this method, thereby do not obtain using in actual production.
Based on the two-forty and the high-quality of HVPE method growing nitride, HVPE is used for the substrate and the template of growing nitride by people.Because the problem of nitride production efficiency etc., the nitride cost is high, has limited the especially extremely important general illumination of cost field of its possibility that is used for LED greatly.HVPE growing nitride template is one of feasible LED growth substrates, but the removal problem that faces initial substrates such as sapphire etc. equally makes HVPE nitride template be used for making slow progress in the LED growth.
The be applied to HVPE legal system successful from lift-off technology is equipped with the gallium nitride homo-substrate, and Hitachi's cable uses from stripping means and obtains 3 inches gallium nitride substrate and kept very high rate of finished products.But still there are not researcher or company to use so far from the grow gallium nitride based LED of vertical stratification of stripping means.Even its reason mainly be the nitride LED of MOCVD growth can be from peeling off also since thickness cross thin and can't realize self-supporting; Use HVPE thick film template to be used for often not possessing of LED preparation, can't peel off certainly but nitride and substrate form strong bonding from the up-stripping layer of peeling off.
The present invention just is being based on the analysis to above method, accurately control LED structure and weak bond in conjunction with HVPE high-speed rapid growth nitride, MOCVD growth and close peeling off certainly of realization, growth can self-supporting the nitride LED structural material and be used for the preparation of vertical stratification LED, can satisfy the large-scale production requirement of general illumination high-performance, low cost and high finished product rate fully, will help semiconductor lighting to move towards general illumination.
The present invention is specially adapted to realize disposable epitaxial growth of gallium nitride based vertical structure LED epitaxial material on the equipment of HVPE and MOCVD combination such as MOHVPE or the SHMOCVD, it is simple to have process route, the rate of finished products height, advantages such as material property is good are the effective solutions of realizing low cost, high-performance and the high finished product rate of nitride vertical stratification LED.Certainly the repeatedly extension that also can be used for HVPE and MOCVD makes up and realizes identical vertical stratification LED.
Summary of the invention
The preparation method who the purpose of this invention is to provide a kind of nitride LED with vertical structure, solve to realizing high-performance, high finished product rate and the stripping technology difficult problem in the nitride LED with vertical structure cheaply, be particularly suitable for MOHVPE by combining HVPE and MOCVD or SHMOCVD equipment and grow and realize from the nitride LED epitaxial material of peeling off; Can certainly utilize MOCVD and HVPE equipment to carry out relevant growth respectively and finally realize identical materials structure and device technology.
For reaching top purpose, the invention provides a kind of preparation method of nitride LED with vertical structure, it is characterized in that, comprise the steps:
Step 1: the substrate of getting a growth nitride;
Step 2: growth up-stripping layer on substrate, this peel ply make between substrate and the follow-up epitaxial material bonding relatively a little less than, can realize separating automatically of substrate and epitaxial loayer by heating and cooling or external force effect;
Step 3: on the up-stripping layer, adopt MOCVD method growing nitride nucleating layer, guarantee the high-quality of nitride;
Step 4: on the nitride nucleating layer, adopt HVPE method growth one deck gallium nitride thick layer of material, so that follow-up epitaxial material can the oneself support;
Step 5: on the gallium nitride thick layer of material, adopt MOCVD method growth Multiple Quantum Well LED structure sheaf, form the luminescent layer of nitride LED, wherein the preparation of p type nitride can realize by HVPE;
Step 6: at the bottom of the peeling liner and up-stripping layer and part nitride nucleating layer, obtain the nitride LED epitaxial wafer of vertical stratification;
Step 6: on Multiple Quantum Well LED structure sheaf, make top electrode;
Step 7: below the nitride nucleating layer that links to each other with epitaxial loayer, make a bottom electrode, finish the preparation of nitride LED with vertical structure.
Wherein said substrate is sapphire or silicon or carborundum.
Wherein said up-stripping layer is metal or dielectric material, comprises Ti, Al, Ni, Cr, Au, W, SiO
2, SiN, TiN or TiO
2
Wherein Multiple Quantum Well LED structure sheaf has p type nitride layer, adopts the method for HVPE can realize higher p type doping efficiency and carrier concentration.
Wherein the gallium nitride thick layer of material needs at least 10 μ m above so that can have the intensity of self-supporting.
The preparation method's of a kind of nitride LED with vertical structure of the present invention beneficial effect is:
1) form the up-stripping layer on the gallium nitride-based epitaxial material substrate, this up-stripping layer can be metal or dielectric material, comprises Ti, Al, Ni, Cr, Au, W, SiO
2, SiN, TiN or TiO
2, the weak bond that its purpose is to form between substrate and the epitaxial loayer closes so that need not the technology of relative complex such as laser lift-off or mechanical lapping or corrosion easily from peeling off;
2) utilize the MOCVD pattern to grow into stratum nucleare, guarantee that nitride is from beginning promptly to have higher quality;
3) utilize high growth rates and the high efficiency of HVPE, growth thickness is enough to realize the thick-layer nitride material of epitaxial material self-supporting;
4) utilize the technical characterstic of MOCVD High Accuracy Control, obtain the LED device architecture, highly doped for p type nitride wherein, can use HVPE to grow nitride layer that high p mixes;
5) realize peeling off certainly of gallium nitride and substrate by the up-stripping layer of gallium nitride and substrate, thereby realize the nitride LED epitaxial wafer of vertical stratification;
6) by removing corresponding process meanses such as the nonconducting nucleating layer of part, preparation top electrode, preparation bottom electrode, realize the manufacturing of the nitride LED of vertical stratification.
Description of drawings
For further specifying content of the present invention, below in conjunction with concrete case study on implementation and accompanying drawing the present invention is done a detailed description, wherein:
Fig. 1 is preparation method's flow chart of embodiments of the invention;
Fig. 2 can peel off vertical stratification LED material structure figure certainly;
Fig. 3 is a vertical stratification LED structural representation.
Embodiment
See also shown in Figure 1, simultaneously please in conjunction with consulting Fig. 2 and Fig. 3, preparation method's flow chart schematic diagram of case study on implementation of the present invention, we select Sapphire Substrate is but that example the present invention is not limited to Sapphire Substrate, other substrates are suitable equally, the committed step of back also not only is confined to the description of present embodiment, and will cover the scope that claims comprise.
At first go up the up-stripping layer 20 (step S2) that forms metal or medium at substrate 10 (step S1) by deposition, growth or suitable technical process, such as the netted texture thin layer of TiN, metal texture film etc., it mainly acts on the weak bond that is to form between substrate 10 and the nitride nucleating layer 30 and closes to realize peeling off certainly of substrate 10 and nitride nucleating layer 30, forming texture simultaneously also is good horizontal extension structure, helps to improve the crystal mass of nitride epitaxial; Described substrate 10 is sapphire or silicon or carborundum; Described up-stripping layer 20 is metal or dielectric material, comprises Ti, Al, Ni, Cr, Au, W, SiO
2, SiN, TiN or TiO
2
Next utilizes nitride nucleating layer 30 (the step S of MOCVD growing high-quality
3), use general two-step method can obtain the nucleating layer of crystal mass far above HVPE;
Then utilize two-forty high efficiency growing gallium nitride thick layer of material 40 (the step S4) of HVPE, this thick layer of material need enough thickness with self-supporting after peeling off nitride epitaxial structure and need not nitride epitaxial structure is bonded on any other substrate again, its thickness is at least more than 10 μ m, the crystal mass that other people's experiment simultaneously also confirms nitride is along with the increase of thickness increases gradually, but thickness neither be thick more good more, also need the compromise physical characteristic of considering production efficiency and thick film, be advisable not produce too big sample warpage and crackle etc.;
Utilize the accurately controlled growth that is grown in realization Multiple Quantum Well LED structure sheaf 50 (step S5) on the gallium nitride thick layer of material 4 of MOCVD then, the characteristics that the p type layer of Multiple Quantum Well LED structure sheaf 50 can utilize the high p of HVPE to mix efficient and high carrier concentration are prepared;
Just utilize the up-stripping layer 20 that weak bond closes between substrate and the nitride more then, realize separate (the step S6) of substrate 10 and nitride nucleating layer 30 by heating and cooling or very little external force, substrate 10 can further be saved the LED manufacturing cost by handling once more to reuse;
By removing the nonconducting nitride nucleating layer 30 in epitaxial wafer top, the processing step (step S7) of preparation top electrode 60 and bottom electrode 70 obtains the nitride LED with vertical structure preparation of devices at last, thereby realizes the potential performance advantage of nitride LED.
See also the preparation method of Fig. 2, Fig. 3 and the described a kind of nitride LED with vertical structure of Fig. 1 again, it is characterized in that: at first need on gallium nitride-based epitaxial material substrate 10, form up-stripping layer 20, this peel ply 20 make between substrate 10 and the nitride epitaxial material bonding relatively a little less than, can separate automatically down by suitable heating and cooling or very little external force effect.
The preparation method of described a kind of nitride LED with vertical structure, it is characterized in that: combine HVPE and MOCVD growth pattern, can be in MOHVPE or SHMOCVD, to use MOCVD pattern growing nitride nucleating layer 30 successively, HVPE pattern growing gallium nitride thick layer of material 40, MOCVD pattern growth Multiple Quantum Well LED structure sheaf 50.
The preparation method of described a kind of nitride LED with vertical structure, it is characterized in that: combine HVPE and MOCVD growth pattern, it can be MOCVD epitaxial furnace growing nitride nucleating layer 30, take out secondary epitaxy gallium nitride thick layer of material 40 in the HVPE epitaxial furnace then, enter three extension Multiple Quantum Well LED structure sheafs 50 among the MOCVD at last once more.
The preparation method of described a kind of nitride LED with vertical structure is characterized in that, the p type nitride layer of Multiple Quantum Well LED structure sheaf can be realized by MOCVD or HVPE method, realizes higher p type doping efficiency and carrier concentration with expectation.
The preparation method of described a kind of nitride LED with vertical structure is characterized in that, gallium nitride thick layer of material 40 need have enough thickness can have enough intensity to realize self-supporting to realize the epitaxial material after peeling off.
Realize that the present invention preferably can be in conjunction with HVPE and MOCVD, the mode of MOHVPE or SHMOCVD that realizes is carried out, can utilize HVPE high-speed rapid growth and the MOCVD control of growing accurately, by inserting the up-stripping layer, the disposable epitaxial material that can be used for directly preparing nitride LED with vertical structure that grows is realized high efficiency, low cost and high performance combination.Secondly also can utilize MOCVD and HVPE to carry out repeatedly extension respectively obtains the identical materials structure and obtains nitride LED with vertical structure 70 by identical technology.
Can effectively realize laying the foundation high efficiency, low cost and the high-performance of nitride LED with vertical structure by this method for nitride LED enters the general illumination field.
Claims (5)
1. the preparation method of a nitride LED with vertical structure is characterized in that, comprises the steps:
Step 1: the substrate of getting a growth nitride;
Step 2: growth up-stripping layer on substrate, this peel ply make between substrate and the follow-up epitaxial material bonding relatively a little less than, can realize separating automatically of substrate and epitaxial loayer by heating and cooling or external force effect;
Step 3: on the up-stripping layer, adopt MOCVD method growing nitride nucleating layer, guarantee the high-quality of nitride;
Step 4: on the nitride nucleating layer, adopt HVPE method growth one deck gallium nitride thick layer of material, so that follow-up epitaxial material can the oneself support;
Step 5: on the gallium nitride thick layer of material, adopt MOCVD method growth Multiple Quantum Well LED structure sheaf, form the luminescent layer of nitride LED, wherein the preparation of p type nitride can realize by HVPE;
Step 6: at the bottom of the peeling liner and up-stripping layer and part nitride nucleating layer, obtain the nitride LED epitaxial wafer of vertical stratification;
Step 6: on Multiple Quantum Well LED structure sheaf, make top electrode;
Step 7: below the nitride nucleating layer that links to each other with epitaxial loayer, make a bottom electrode, finish the preparation of nitride LED with vertical structure.
2, the preparation method of a kind of nitride LED with vertical structure according to claim 1 is characterized in that, wherein said substrate is sapphire or silicon or carborundum.
3, the preparation method of a kind of nitride LED with vertical structure according to claim 1 is characterized in that, wherein said up-stripping layer is metal or dielectric material, comprises Ti, Al, Ni, Cr, Au, W, SiO
2, SiN, TiN or TiO
2
4, the preparation method of a kind of nitride LED with vertical structure according to claim 1 is characterized in that, wherein Multiple Quantum Well LED structure sheaf has p type nitride layer, adopts the method for HVPE can realize higher p type doping efficiency and carrier concentration.
5, the preparation method of a kind of nitride LED with vertical structure according to claim 1 is characterized in that, wherein the gallium nitride thick layer of material needs at least 10 μ m above so that can have the intensity of self-supporting.
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102157650A (en) * | 2011-01-31 | 2011-08-17 | 浙江大学 | Method for manufacturing gallium nitride (GaN)-based light-emitting diode (LED) with vertical structure |
| CN102255026A (en) * | 2010-08-02 | 2011-11-23 | 中山大学佛山研究院 | Gallium nitride light-emitting diode chip with vertical structure and manufacturing method thereof |
| CN102265414A (en) * | 2010-10-26 | 2011-11-30 | 香港应用科技研究院有限公司 | Method for manufacturing light emitting diode with vertical structure |
| CN102479887A (en) * | 2010-11-25 | 2012-05-30 | 萧介夫 | Epitaxy element preparation method |
| CN106341095A (en) * | 2016-08-31 | 2017-01-18 | 中国科学院半导体研究所 | On-metal monocrystal nitride film preparation method and bulk acoustic wave resonator |
| CN110838539A (en) * | 2019-11-25 | 2020-02-25 | 佛山市国星半导体技术有限公司 | Silicon-based gallium nitride epitaxial structure and manufacturing method thereof |
| CN110838539B (en) * | 2019-11-25 | 2024-04-30 | 佛山市国星半导体技术有限公司 | Silicon-based gallium nitride epitaxial structure and manufacturing method thereof |
-
2008
- 2008-03-26 CN CN200810102801A patent/CN101546799A/en active Pending
Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102255026B (en) * | 2010-08-02 | 2013-08-07 | 中山大学佛山研究院 | Gallium nitride light-emitting diode chip with vertical structure and manufacturing method thereof |
| CN102255026A (en) * | 2010-08-02 | 2011-11-23 | 中山大学佛山研究院 | Gallium nitride light-emitting diode chip with vertical structure and manufacturing method thereof |
| CN102265414A (en) * | 2010-10-26 | 2011-11-30 | 香港应用科技研究院有限公司 | Method for manufacturing light emitting diode with vertical structure |
| WO2012055252A1 (en) * | 2010-10-26 | 2012-05-03 | Hong Kong Applied Science And Technology Research Institute Co. Ltd. | Method for fabricating vertical led structures |
| CN102265414B (en) * | 2010-10-26 | 2013-04-03 | 香港应用科技研究院有限公司 | Method for manufacturing light emitting diode with vertical structure |
| CN102479887A (en) * | 2010-11-25 | 2012-05-30 | 萧介夫 | Epitaxy element preparation method |
| CN102479887B (en) * | 2010-11-25 | 2013-12-04 | 萧介夫 | Epitaxy element preparation method |
| CN102157650B (en) * | 2011-01-31 | 2013-06-12 | 浙江大学 | Method for manufacturing gallium nitride (GaN)-based light-emitting diode (LED) with vertical structure |
| CN102157650A (en) * | 2011-01-31 | 2011-08-17 | 浙江大学 | Method for manufacturing gallium nitride (GaN)-based light-emitting diode (LED) with vertical structure |
| CN106341095A (en) * | 2016-08-31 | 2017-01-18 | 中国科学院半导体研究所 | On-metal monocrystal nitride film preparation method and bulk acoustic wave resonator |
| CN106341095B (en) * | 2016-08-31 | 2020-04-07 | 中国科学院半导体研究所 | Method for preparing monocrystal nitride film on metal and bulk acoustic wave resonator |
| CN110838539A (en) * | 2019-11-25 | 2020-02-25 | 佛山市国星半导体技术有限公司 | Silicon-based gallium nitride epitaxial structure and manufacturing method thereof |
| CN110838539B (en) * | 2019-11-25 | 2024-04-30 | 佛山市国星半导体技术有限公司 | Silicon-based gallium nitride epitaxial structure and manufacturing method thereof |
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Open date: 20090930 |