CN101369599B - Ohm contact of gallium nitride base device and preparation method thereof - Google Patents
Ohm contact of gallium nitride base device and preparation method thereof Download PDFInfo
- Publication number
- CN101369599B CN101369599B CN2008102120534A CN200810212053A CN101369599B CN 101369599 B CN101369599 B CN 101369599B CN 2008102120534 A CN2008102120534 A CN 2008102120534A CN 200810212053 A CN200810212053 A CN 200810212053A CN 101369599 B CN101369599 B CN 101369599B
- Authority
- CN
- China
- Prior art keywords
- metal layer
- ohmic contact
- gallium nitride
- based device
- annealing
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Images
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
- Y02P70/50—Manufacturing or production processes characterised by the final manufactured product
Landscapes
- Electrodes Of Semiconductors (AREA)
Abstract
本发明公开了一种氮化镓基器件的欧姆接触及其制备方法，属于半导体技术领域。该氮化镓基器件的欧姆接触，由钛金属层、铝金属层、阻挡金属层和金金属层组成，与氮化镓基器件欧姆接触的是钛金属层，钛金属层上覆盖铝金属层，在钛金属层和铝金属层上依次覆盖阻挡金属层和金金属层，其中，钛金属层和铝金属层重叠排列2—10个周期。与传统欧姆接触结构相比，本发明基于多层Ti/Al结构的欧姆接触能够兼顾低比欧姆接触率，且具有好的表面形貌和高可靠性，能够提高欧姆接触的综合性能。对于实现高性能、高可靠性的氮化镓基器件具有重要意义。
The invention discloses an ohmic contact of a gallium nitride-based device and a preparation method thereof, belonging to the technical field of semiconductors. The ohmic contact of the gallium nitride-based device is composed of a titanium metal layer, an aluminum metal layer, a barrier metal layer and a gold metal layer. The ohmic contact with the gallium nitride-based device is a titanium metal layer, and the titanium metal layer is covered with an aluminum metal layer. A barrier metal layer and a gold metal layer are sequentially covered on the titanium metal layer and the aluminum metal layer, wherein the titanium metal layer and the aluminum metal layer are overlapped and arranged for 2-10 periods. Compared with the traditional ohmic contact structure, the ohmic contact based on the multilayer Ti/Al structure of the present invention can take into account the low specific ohmic contact ratio, and has good surface morphology and high reliability, and can improve the comprehensive performance of the ohmic contact. It is of great significance to realize GaN-based devices with high performance and high reliability.
Description
Technical field
The invention relates to the gallium-nitride-based devices in the technical field of semiconductors, be specifically related to ohmic contact of a kind of gallium-nitride-based devices and preparation method thereof.
Background technology
The device that with AlGaN/GaN is material foundation is referred to as gallium-nitride-based devices, AlGaN/GaN hetero junction field effect pipe (heterostructurefield effect transistors for example, HFET), heterojunction bipolar transistor (heterostructure bipolar transistor, HBT) etc.Gallium-nitride-based devices has advantages such as working temperature height, breakdown field is powerful, cut-off frequency is high, power density is big, is the first-selection in following microwave high power field, more becomes the nearly research emphasis in microwave power device field during the last ten years.
Be different from traditional Si device, the GaN system, gallium-nitride-based devices can not form ohmic contact by semi-conducting material is carried out heavy doping, detailed process is: at first pass through the metal that magnetron sputtering or electron beam evaporation deposit need on semi-conductive surface, (temperature Centralized is in 750 ℃～900 ℃ then they to be carried out rapid thermal annealing, time is 30S～60S), could form the ohmic contact that meets the requirements afterwards.Therefore, in the formation of gallium-nitride-based devices, ohmic contact can influence the knee voltage of device, total mutual conductance, so that gross output, and the pattern of ohmic contact further also can influence the subsequent optical carving technology of device, the microwave noise characteristic of device, so the reliability of gallium-nitride-based devices ohmic contact has directly determined the reliability of device.
The ohmic contact of the gallium-nitride-based devices of now having reported at present, comprises:
1, the research of earliest period is to utilize Ti/Al or the such double-decker of Al/Ti---earlier at the semiconductor surface depositing metal, and rapid thermal annealing under nitrogen atmosphere then.This technology can not obtain less specific contact resistivity rate, because the easy oxidation of metal.
2, technology progressively develops, and the Ti/Al/Au three-decker occurs, and the Au on top layer is used to protect ohmic metal not oxidated.But do not obtain desirable specific contact resistivity rate (1E-6 Ω .cm
2).
3, subsequently, gallium-nitride-based devices ohmic contact technology four layers of metal structure: Ti/Al/Ni (Pt, Mo, Ti, Ir etc. the)/Au that adopt more.Wherein with Ti/Al/Ni/Au and Ti/Al/Mo/Au for the most extensive.This ohmic contact preparating mechanism is: and the immediate Ti of AlGaN/GaN heterostructure, in the process of rapid thermal annealing and AlGaN/GaN react, from the GaN system, capture the N element, reaction generates TiN and also causes the N room in the GaN system.TiN is the material of a kind of low work function (3.7ev), the ohmic metal that helps forming; And the N room is the n type doping in the GaN system, the good ohmic metal of also favourable formation.Reaction for auxiliary Ti and GaN system; on Ti, cover Al; in order to protect Ti; the metal of two kinds of easy oxidations of Al is not oxidized; the Au of adequate thickness need be covered topmost,, one deck barrier metal need be between Au and Al, added in order to stop the sinking of Au; as Ni, Pt, Mo, Ti, Ir etc., constitute the ohmic contact of Ti/Al/Ni/Au system.
At present, researcher's energy focuses mostly on the annealing conditions of seeking optimum Ti/Al ratio and optimum.But in actual result, the effect of finding the Al in the ohmic contact of above-mentioned Ti/Al/Ni/Au system not only as above-mentioned institute say that its effect also needs further research; And as the Ni of barrier metal, the also counterdiffusion between barrier metal fully, the concrete role of these metals also will further be studied.This is because in the process of rapid thermal annealing, Ti and Al at first react in the time of 250 ℃ and generate TiAl
3How many materials of this Heat stability is good, its amount have determined the amount of the Ti-Al (alloy or simple two kinds of metals) of remaining energy and the reaction of GaN system, have determined the quality of ohmic contact.Therefore, the ohmic contact of gallium-nitride-based devices such as AlGaN/GaN HFET has greatly attracted researcher's attentiveness.
Summary of the invention
The object of the present invention is to provide ohmic contact of a kind of gallium-nitride-based devices and preparation method thereof, the electric property of this ohmic contact and Heat stability is good, its surperficial projection size diminishes, the evenness height.
Technical scheme of the present invention is:
A kind of ohmic contact of gallium-nitride-based devices, form by titanium coating, aluminum metal layer, barrier metal layer and gold metal layer, wherein, with the gallium-nitride-based devices ohmic contact be titanium coating, covering aluminum metal layer on the titanium coating, on titanium coating and aluminum metal layer, cover barrier metal layer and gold metal layer successively, it is characterized in that, 2～10 cycles of the overlapping arrangement of above-mentioned titanium coating and aluminum metal layer.
Described titanium coating gross thickness is 20～50nm.
The thickness of described titanium coating and aluminum metal layer is than being 1:2～1:12.
Described barrier metal layer adopts a kind of in nickel, platinum, molybdenum, titanium and the iridium.
A kind of preparation method of ohmic contact of gallium-nitride-based devices, its step comprises:
1) at the surface of gallium-nitride-based devices difference deposit titanium coating as claimed in claim 1, aluminum metal layer, barrier metal layer and gold metal layer;
2) above-mentioned metal level is carried out rapid thermal annealing, form ohmic contact.
Adopt magnetron sputtering or electron beam evaporation technique deposited metal in the step 1).
After the step 1), the gallium-nitride-based devices of deposited metal is ultrasonic in acetone, form ohm figure.
Step 2) adopt the double annealing mode in, promptly the temperature range of annealing is 800～900 ℃ for the first time, and the time is 20～45 seconds; The temperature range of annealing is 400～600 ℃ for the second time, and the time is 60～180 seconds.
Compared with prior art, the invention has the beneficial effects as follows:
The present invention has adopted the ohmic contact based on multilayer Ti/Al structure, and it is split into several parts with Ti/Al under the situation of gross thickness that keeps Ti and Al and constant rate, and then covers the Ni/Au structure.It has solved the problem that exists in traditional four-layer structure ohmic contact well.The reasons are as follows:
1, increased the contact interface of Ti/Al, made their reactions more even, and form the wider TiAl that distributes
3Thereby, improved the ohmic contact thermal stability.Simultaneously, sandwich construction has fully been fixed the effluent of Al.
2, reduced absolute thickness, the severe degree of reaction is alleviated, improved thermal stability near the Ti/Al of GaN system.
Than traditional ohmic contact structure, the ohmic contact that the present invention is based on multilayer Ti/Al structure can be taken into account low than ohmic contact rate (the obtainable contact resistance of unit contact area, the specific contact resistivity rate is low more, total Ohmic resistance is more little), good surface topography and high reliability index, improve the combination property of ohmic contact, further improve the practicability of gallium nitride HFET device, significant for the gallium-nitride-based devices of realizing high-performance, high reliability.
Description of drawings
Fig. 1 is a conventional structure Ti/Al/Ni/Au ohmic contact structural representation; Wherein, 1-gold metal layer; 2-barrier metal layer; 3-aluminum metal layer; 4-titanium coating; 5-gallium-nitride-based devices.
Fig. 2 is an ohmic contact structural representation of the present invention; Wherein, 1-gold metal layer; 2-barrier metal layer; 3-aluminum metal layer; 4-titanium coating; 5-gallium-nitride-based devices.
Fig. 3 is the pattern comparison diagram of the present invention and traditional structure ohmic contact.
Embodiment
Below in conjunction with the drawings and specific embodiments the present invention is described in further detail:
With AlGaN/GaN HFET device is example, and concrete technical scheme is as follows:
(1) lithographic device ohmic metal structure domain;
(2) deposit of metal-layer structure is adopted magnetron sputtering deposit Ti5nm successively, Al30nm, Ti5nm, Al30nm, Ti5nm, Al30nm, Ti5nm, Al30nm, Ni50nm, Au200nm.
(3) peel off: the device print of depositing metal is ultrasonic in acetone, forms ohm figure.
(4) rapid thermal annealing: with the cleaned quick anneal oven of putting into then of device print, adopt the twice annealing scheme: the temperature range of annealing is 800～900 ℃ for the first time, and the time is 30S; The temperature range of annealing is 400～600 ℃ for the second time, and the time is 120S.
The resistivity of the ohmic contact of present embodiment and traditional structure ohmic contact compares:
| ρc(Ω·cm 2) | Rc(Ω·mm) | |
| Traditional structure Ti/Al/Ni/Au (20/120/50/200nm) | 1.32E-05 | 0.752 |
| Structure Ti/Al/....Ni/Au of the present invention (5/30....50/200nm) | 8.74E-07 | 0.22 |
The pattern of present embodiment ohmic contact and traditional ohmic contact compares: in Fig. 3, (a) (b) be the surface topography of traditional structure ohmic contact, as seen its pattern is relatively poor, and under high power, as seen the crack is arranged in protrusion of surface, and this will influence the high frequency characteristics of device greatly; In Fig. 3, (c) (d) is the surface topography of ohmic contact of the present invention.The projection of visible surface reduces (can be drawn by photo medium scale amount) greatly, and does not have the crack on the visible projection under high power, and this can improve the high frequency characteristics of device greatly.
The high high-temp stability of present embodiment ohmic contact and traditional ohmic contact compares: found through experiments, ohmic contact of the present invention can wear out 8 hours under 400 ℃ of high temperature and make the variation of specific contact resistivity rate very little; And the traditional structure ohmic contact was through 2 hours serious degradations.
The related device of the foregoing description is not limited to the explanation of this example, not only can be AlGaN/GaN HFET device, can also be AlGaN/GaN HBT, GaN base LED, laser, gallium-nitride-based devices such as GaN base ultraviolet light detector.
Among the present invention, the foregoing description provides a kind of gallium-nitride-based devices ohmic contact structure and preparation scheme optimized, the present invention not only is confined to this embodiment, can make corresponding modification with designing requirement according to actual needs, for example: it is 4 that the arrangement cycle of titanium coating and aluminum metal layer is provided among the embodiment, but the arrangement of corresponding titanium coating and aluminum metal layer can be 2-10 cycles.
Described titanium coating gross thickness is 20～50nm, and the thickness of described titanium coating and aluminum metal layer is than being 1:2～1:12.And barrier metal layer can be in nickel, platinum, molybdenum, titanium and the iridium any one.
In addition, provide the method for magnetron sputtering deposited metal among the embodiment, but corresponding structure can realize also by electron beam evaporation technique.
In addition, the annealing region first time of double annealing scheme is 800～900 ℃, and the time is 20～45S; Annealing region is 400～600 ℃ for the second time, and the time is 60～180 seconds.
More than by specific embodiment the ohmic contact of gallium-nitride-based devices of the present invention has been described, it will be understood by those of skill in the art that in the scope that does not break away from essence of the present invention, can make certain deformation or modification to the present invention; Its preparation method also is not limited to disclosed content among the embodiment.
Claims (3)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2008102120534A CN101369599B (en) | 2008-07-11 | 2008-09-16 | Ohm contact of gallium nitride base device and preparation method thereof |
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN200810116583.9 | 2008-07-11 | ||
| CN200810116583 | 2008-07-11 | ||
| CN2008102120534A CN101369599B (en) | 2008-07-11 | 2008-09-16 | Ohm contact of gallium nitride base device and preparation method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN101369599A CN101369599A (en) | 2009-02-18 |
| CN101369599B true CN101369599B (en) | 2011-02-16 |
Family
ID=40413311
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2008102120534A Expired - Fee Related CN101369599B (en) | 2008-07-11 | 2008-09-16 | Ohm contact of gallium nitride base device and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN101369599B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| RU2756579C1 (en) * | 2020-12-16 | 2021-10-01 | Акционерное общество "Научно-производственное предприятие "Исток" имени А.И. Шокина" (АО "НПП "Исток" им. Шокина") | Method for manufacturing ohmic contacts of powerful electronic devices |
Families Citing this family (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20110291147A1 (en) * | 2010-05-25 | 2011-12-01 | Yongjun Jeff Hu | Ohmic contacts for semiconductor structures |
| US8466555B2 (en) * | 2011-06-03 | 2013-06-18 | Raytheon Company | Gold-free ohmic contacts |
| CN102290478B (en) * | 2011-09-05 | 2016-03-09 | 中国电子科技集团公司第十八研究所 | A kind of p-i-n type unijunction InGaN solar cell |
| CN104426054A (en) * | 2013-09-02 | 2015-03-18 | 长贝光电（武汉）有限公司 | Packaging method of semiconductor laser device |
| CN107799641A (en) * | 2016-09-05 | 2018-03-13 | 泰谷光电科技股份有限公司 | Electrode structure of light-emitting diode |
| CN108376703B (en) * | 2018-01-11 | 2021-04-06 | 北京华碳科技有限责任公司 | An ohmic contact fabrication method suitable for AlGaN/GaN devices |
| CN108389954B (en) * | 2018-01-11 | 2019-11-22 | 河源市众拓光电科技有限公司 | A kind of superstructure LED chip and preparation method thereof |
| CN111129251A (en) * | 2019-12-30 | 2020-05-08 | 广东德力光电有限公司 | Electrode structure of high-weldability flip LED chip |
| CN111029457A (en) * | 2019-12-31 | 2020-04-17 | 合肥彩虹蓝光科技有限公司 | Packaging structure and packaging method of deep ultraviolet light emitting diode |
| CN115347452A (en) * | 2021-05-12 | 2022-11-15 | 常州纵慧芯光半导体科技有限公司 | A semiconductor device and its cathode structure |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5844347A (en) * | 1995-09-01 | 1998-12-01 | Matsushita Electric Industrial Co., Ltd. | Saw device and its manufacturing method |
| CN1734728A (en) * | 2004-08-09 | 2006-02-15 | 中国科学院微电子研究所 | Al/Ti/Pt/Au ohmic contact system suitable for GaN device |
| CN1734732A (en) * | 2004-08-09 | 2006-02-15 | 中国科学院微电子研究所 | Al/Ti/Au ohmic contact system suitable for GaN device |
| CN1787235A (en) * | 2004-12-08 | 2006-06-14 | 方大集团股份有限公司 | Method for improving ohmic contact alloy of gallium nitrate based semiconductor LED |
-
2008
- 2008-09-16 CN CN2008102120534A patent/CN101369599B/en not_active Expired - Fee Related
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5844347A (en) * | 1995-09-01 | 1998-12-01 | Matsushita Electric Industrial Co., Ltd. | Saw device and its manufacturing method |
| CN1734728A (en) * | 2004-08-09 | 2006-02-15 | 中国科学院微电子研究所 | Al/Ti/Pt/Au ohmic contact system suitable for GaN device |
| CN1734732A (en) * | 2004-08-09 | 2006-02-15 | 中国科学院微电子研究所 | Al/Ti/Au ohmic contact system suitable for GaN device |
| CN1787235A (en) * | 2004-12-08 | 2006-06-14 | 方大集团股份有限公司 | Method for improving ohmic contact alloy of gallium nitrate based semiconductor LED |
Non-Patent Citations (6)
| Title |
|---|
| 刘岳巍等.GaN HEMT外延材料欧姆接触的研究.河北工业大学学报35 2.2006,35(2),52-55. |
| 刘岳巍等.GaN HEMT外延材料欧姆接触的研究.河北工业大学学报35 2.2006,35(2),52-55. * |
| 劭庆辉等.二次退火对Al/Ti/n-GaN/Si欧姆接触的影响.微纳器件与技术 1.2003,(1),12-14. |
| 劭庆辉等.二次退火对Al/Ti/n-GaN/Si欧姆接触的影响.微纳器件与技术 1.2003,(1),12-14. * |
| 杨燕等.AlGaN/GaN 异质结构的欧姆接触.半导体学报27 10.2006,27(10),1823-1827. |
| 杨燕等.AlGaN/GaN 异质结构的欧姆接触.半导体学报27 10.2006,27(10),1823-1827. * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| RU2756579C1 (en) * | 2020-12-16 | 2021-10-01 | Акционерное общество "Научно-производственное предприятие "Исток" имени А.И. Шокина" (АО "НПП "Исток" им. Шокина") | Method for manufacturing ohmic contacts of powerful electronic devices |
Also Published As
| Publication number | Publication date |
|---|---|
| CN101369599A (en) | 2009-02-18 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101369599B (en) | Ohm contact of gallium nitride base device and preparation method thereof | |
| CN100380678C (en) | Semiconductor device with Schottky junction electrode | |
| JP3512659B2 (en) | Nitride III-V compound semiconductor device | |
| JP4866007B2 (en) | Compound semiconductor device | |
| CN102651394A (en) | Semiconductor device and method of manufacturing the same, and power supply apparatus | |
| CN101414629B (en) | Source field plate transistor with high electron mobility | |
| US9934978B2 (en) | Method of fabricating an electrical contact for use on a semiconductor device | |
| CN114156339A (en) | Bidirectional blocking HEMT based on composite channel structure and preparation method thereof | |
| CN103700580A (en) | Method for preparing SiC ohmic contact by ultraviolet pulse laser irradiation device | |
| JP2008147294A (en) | Electronic device | |
| JP2010086999A (en) | Back electrode for semiconductor device, semiconductor device, and manufacturing method of back electrode for semiconductor device | |
| CN101414622A (en) | Composite field plate heterojunction field effect transistor based on source field plate and leakage field plate | |
| CN109037050A (en) | Preparation method of TiN-based GaN-based HEMT gold-free ohmic contact electrode | |
| CN110581169B (en) | GaN-based HEMT device source-drain electrode with protective layer and preparation method thereof | |
| JP2005277240A (en) | Ohmic electrode of silicon-carbide semiconductor, and manufacturing method thereof | |
| JP5375497B2 (en) | Semiconductor device and method for manufacturing semiconductor device | |
| CN108364864A (en) | The preparation method of AlGaN/GaN HEMT device Ohm contact electrodes | |
| CN116936644A (en) | An N-polar Schottky barrier diode and its preparation method and application | |
| JP3344416B2 (en) | Semiconductor device and method of manufacturing the same | |
| JP4977466B2 (en) | Schottky electrode for nitride semiconductor device and method for manufacturing the same | |
| TW200845361A (en) | Method and structure for reducing cracks in a dielectric layer in contact with metal | |
| CN100481346C (en) | Al/Ti/Al/Ni/Au Ohmic Contact System for GaN Devices | |
| CN114156340A (en) | High electron mobility transistor based on composite channel structure and preparation method thereof | |
| CN117525166A (en) | Multi-channel Schottky barrier diode and preparation method and application thereof | |
| JP2011249828A (en) | Compound semiconductor device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C17 | Cessation of patent right | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20110216 Termination date: 20130916 |