CN104259644A - Welding method of tungsten-titanium alloy target - Google Patents
Welding method of tungsten-titanium alloy target Download PDFInfo
- Publication number
- CN104259644A CN104259644A CN201410357281.6A CN201410357281A CN104259644A CN 104259644 A CN104259644 A CN 104259644A CN 201410357281 A CN201410357281 A CN 201410357281A CN 104259644 A CN104259644 A CN 104259644A
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- CN
- China
- Prior art keywords
- tungsten
- target
- titanium alloy
- aluminum
- alloy target
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- 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.)
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Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K20/00—Non-electric welding by applying impact or other pressure, with or without the application of heat, e.g. cladding or plating
- B23K20/02—Non-electric welding by applying impact or other pressure, with or without the application of heat, e.g. cladding or plating by means of a press ; Diffusion bonding
- B23K20/021—Isostatic pressure welding
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K20/00—Non-electric welding by applying impact or other pressure, with or without the application of heat, e.g. cladding or plating
- B23K20/22—Non-electric welding by applying impact or other pressure, with or without the application of heat, e.g. cladding or plating taking account of the properties of the materials to be welded
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K20/00—Non-electric welding by applying impact or other pressure, with or without the application of heat, e.g. cladding or plating
- B23K20/24—Preliminary treatment
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K2101/00—Articles made by soldering, welding or cutting
- B23K2101/36—Electric or electronic devices
- B23K2101/40—Semiconductor devices
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K2103/00—Materials to be soldered, welded or cut
- B23K2103/18—Dissimilar materials
Abstract
The invention discloses a welding method of a tungsten-titanium alloy target, and belongs to the technical field of semiconductor production. The welding method comprises the following steps: firstly, the tungsten-titanium alloy target and a copper alloy back plate are provided; an aluminum or aluminum alloy layer is formed on the welded surface of the tungsten-titanium target; and then, the tungsten-titanium alloy target is connected to the copper alloy back plate by adopting a diffusion welding method. The method uses the aluminum or aluminum alloy layer to realize the low-temperature welding of the tungsten-titanium alloy target, improves the welding strength of the tungsten-titanium target, prevents the rupture of the target, and enables the target to be suitable for a high-power sputtering process.
Description
Technical field
The invention belongs to technical field of manufacturing semiconductors, be specifically related to a kind of welding method of tungsten-titanium alloy target.
Background technology
In the making of large scale integrated circuit, target material assembly to be combined with backboard to form by meeting target that sputtering requires.Backboard has certain intensity, provides support when target material assembly is mounted to sputtering machine table, has good heat-conductivity conducting performance simultaneously.Tungsten-titanium alloy film, in semiconductor fabrication as diffusion impervious layer, is formed by physical vaporous deposition (PVD) by tungsten-titanium alloy target.Tungsten-titanium alloy target adopts powder sintered mode to prepare, hardness is high, fragility greatly, easily cracked, need with there is high strength & high electric-conduction, the copper backboard of high-termal conductivity carries out welding the target material assembly that just can be processed into needed for semiconductor production, and then carry out magnetron sputtering under certain magnetic field, electric field environment.
In existing sputtering technology, target working environment is comparatively severe, especially high-power sputtering technology, and the sputter temperature of target material assembly is higher, and opposite side then passes to cooling water and carries out cold by force, and both sides produce the huge temperature difference; Under target material assembly sputter face side is in high vacuum environment, the pressure of high-pressure cooling water is then born in backboard side, and both sides form huge pressure differential; Meanwhile, under target material assembly is in stronger magnetic field, electric field action, be subject to the bombardment of various particle.Under rugged environment like this, if target and backboard weld strength poor, target can be caused to ftracture, fracture, even come off from backboard, make sputtering gained uneven film thickness even, unstable properties.In addition, the target come off from backboard also may injure sputtering base station by a crashing object, causes huge economic loss.
Therefore, need to select a kind of rationally effective mode to realize welding of tungsten-titanium alloy target and copper backboard, for the security of sputtering production, stability and sustainability are given security.
At present, tungsten-titanium alloy target mainly adopts indium or indalloy to carry out soldering with welding of copper backboard.Due to indium solder melt point (156 DEG C) and intensity (being less than 20MPa) all very low, can solder fusing be there is when sputtering power is larger, cause target material assembly Joint failure, cause sputter procedure to carry out.
Summary of the invention
The weld strength that the object of the invention is to overcome tungsten titanium target does not reach high-power sputtering requirement, provides a kind of welding method of tungsten-titanium alloy target.
For solving the problem, technical scheme of the present invention is as follows:
A kind of welding method of tungsten-titanium alloy target, comprises the following steps:
(1) carry out processing to tungsten-titanium alloy target and copper alloy backing plate solder side to process;
(2) on tungsten-titanium alloy target solder side, aluminum or aluminum alloy layer is formed;
(3) adopt diffusion welding method that tungsten-titanium alloy target is welded on copper alloy backing plate.
Described tungsten-titanium alloy target is planar targets, and thickness is 1mm ~ 20mm.
Described copper alloy is ormolu, Jackson's alloy or chromiumcopper.
Described processing is treated to be carried out blasting treatment at tungsten-titanium alloy target solder side or processes groove; Groove is processed at copper alloy backing plate solder side.
The roughness of described blasting treatment is 1 μm ~ 15 μm.
The method forming described aluminum or aluminum alloy layer in step (2) is spraying, sputtering, evaporation or directly put into.
Described aluminum or aluminum alloy layer thickness is 0.01mm ~ 10mm.
Described diffusion welding method is: adopt high temperature insostatic pressing (HIP), the temperature of welding is 200 DEG C ~ 600 DEG C, pressure 50 ~ 150MPa, temperature retention time 0.5 ~ 10 hour.
Compared with prior art, the present invention has the following advantages: (1) adopts diffusion welding method two kinds of metals well can be combined, thus realizes the large-area welding of tungsten-titanium alloy target and copper alloy backing plate; (2) between tungsten-titanium alloy target and copper alloy backing plate, aluminum or aluminum alloy is had as intermediate layer, this metallic intermediate layer hardness is low, plasticity good, effectively can cushion the thermal stress and thermal deformation that produce because coefficient-of-linear-expansion difference is comparatively large between tungsten-titanium alloy target and copper alloy backing plate; (3) carry out sandblasting at tungsten titanium target and copper alloy backing plate solder side or process groove, effectively increasing the two and the contact area of aluminum or aluminum alloy layer, add the effective area of layer, improve weld strength.
Accompanying drawing explanation
Fig. 1 is the flow chart that tungsten-titanium alloy target welds with copper alloy backing plate.
Fig. 2 is tungsten titanium alloy target structure schematic diagram;
Fig. 3 is copper alloy backing plate structural representation;
Fig. 4 is the schematic diagram forming aluminum or aluminum alloy layer on the solder side of tungsten-titanium alloy target;
Fig. 5 is the schematic diagram that tungsten-titanium alloy target welds with copper alloy backing plate;
Wherein each label is: 20-tungsten-titanium alloy target, 21-copper alloy backing plate, 200-tungsten-titanium alloy target solder side, 210-copper alloy weld backboard junction, 22-aluminum or aluminum alloy layer.
Detailed description of the invention
Below by the invention will be further described with example with reference to the accompanying drawings.
Fig. 1 is the detailed description of the invention flow chart that tungsten-titanium alloy target of the present invention welds with copper alloy backing plate.As shown in Figure 1, tungsten-titanium alloy target and copper alloy backing plate are provided; Tungsten-titanium alloy target and copper alloy backing plate solder side are processed; The processing of tungsten-titanium alloy target solder side can adopt blasting treatment and machined recess two kinds of modes, and the machined of copper alloy backing plate solder side forms groove; Described groove is a series of donuts being uniformly distributed in solder side, and shape can be circular arc, V-arrangement, rectangle, inverted trapezoidal etc.Then on tungsten-titanium alloy target solder side, aluminum or aluminum alloy layer is formed.Adopt high temperature insostatic pressing (HIP) method to carry out weld job on aluminum or aluminum alloy layer, copper alloy backing plate is welded on tungsten-titanium alloy target.
Fig. 2 to Fig. 5 is the enforcement schematic diagram that tungsten-titanium alloy target of the present invention welds with copper alloy backing plate.
As shown in Figure 2, provide tungsten-titanium alloy target 20, the shape of tungsten-titanium alloy target 20, can be any one of circle, rectangle, triangle, annular etc. according to the requirement of sputtering base station, thickness can be 1mm ~ 20mm.As a preferred embodiment, the shape of tungsten-titanium alloy target 20 is circular, and diameter is 420mm, thickness 12mm.
As shown in Figure 3, provide copper alloy backing plate 21, described copper alloy backing plate 21 material can be brass alloys, tin-brass alloy, chrome copper, corronil, copper nisiloy evanohm etc. any one, but be not limited to above-mentioned alloy.
Carry out processing process to tungsten-titanium alloy target solder side 200 and copper alloy weld backboard junction 210, wherein tungsten-titanium alloy target solder side 200 can carry out blasting treatment, and roughness can be 1 μm ~ 15 μm; Or be processed to form a series of equally distributed concentric annular grooves on tungsten-titanium alloy target solder side 200 and copper alloy backing plate 210, groove shapes can be circular arc, V-arrangement, rectangle, inverted trapezoidal etc.Through blasting treatment and machined grooves, can activating welding face, increase effective weld seam area, improve weld strength.
As shown in Figure 4, the solder side 200 of tungsten-titanium alloy target 20 forms aluminum or aluminum alloy layer 22.The method forming aluminum or aluminum alloy layer 22 has a variety of, the technique such as can adopt spraying, sputtering, evaporation particularly or directly put into, as a preferred embodiment, the mode directly put into can be adopted to form aluminum or aluminum alloy layer, have that technique is simple, cost is low, density advantages of higher.The thickness of described aluminum or aluminum alloy layer 22 can be 0.01mm ~ 10mm.
As shown in Figure 5, carry out Diffusion Welding operation, copper alloy backing plate 21 and tungsten-titanium alloy target 20 are soldered on aluminum or aluminum alloy layer 22.Described Diffusion Welding operation adopts heat and other static pressuring processes, and comprise the following steps: prepare a vacuum canning, described vacuum canning material can be stainless steel, aluminium alloy, mild steel etc.; The tungsten-titanium alloy target 20 and copper alloy backing plate 21 of having aluminum or aluminum alloy layer 22 are put into jacket; Be 10 in vacuum
-3~ 10
-5in Pa environment, jacket is carried out soldering and sealing; The jacket that soldering and sealing is good is put into high temperature insostatic pressing (HIP) stove, is filled with nitrogen or argon gas and is forced into certain value; Be warming up to 200 DEG C ~ 600 DEG C, and be incubated 0.5 ~ 10 hour; High temperature can make the nitrogen in stove or argon gas volumetric expansion thus obtain higher pressure, and pressure is remained on 50MPa ~ 150MPa by holding stage; Heat-insulation pressure keeping process can make to combine with the tungsten-titanium alloy target 20 in intermediate layer 22 and copper alloy backing plate 21, forms target material assembly.
Embodiment 1
Welded with the copper alloy backing plate of diameter 310mm by the tungsten-titanium alloy target of diameter 300mm, wherein tungsten-titanium alloy composition is W-10%Ti, and copper alloy backing plate composition is Cu-0.7%Cr.
First tungsten titanium target material solder side is carried out blasting treatment, roughness 4.3 μm, uniformity.Copper alloy backing plate solder side lathe in machining V-type groove, degree of depth 0.4mm, separation 0.5mm.
The commercial-purity aluminium of the trade mark 1050 is selected in intermediate layer, thickness 2mm.
The copper alloy backing plate machined, 1050 aluminium flakes, tungsten titanium target material are put into 6061 aluminium alloy jackets, successively 8 × 10
-3electron beam soldering and sealing in Pa vacuum.
What soldering and sealing completed be wrapped in high temperature insostatic pressing (HIP) stove welds, and temperature 500 DEG C, pressure 100MPa, heat-insulation pressure keeping takes out air cooling to room temperature after cooling to 200 DEG C with the furnace after 5 hours.
Carry out C-Scan detection after jacket is removed in the machined of embodiment exemplar, solder bond rate reaches more than 99%, tested for tensile strength, and average weld strength reaches more than 93MPa.This method is adopted to obtain tungsten-titanium alloy target welding performance reliable.
Claims (8)
1. a welding method of tungsten-titanium alloy target, is characterized in that, comprises the following steps:
(1) carry out processing to tungsten-titanium alloy target and copper alloy backing plate solder side to process;
(2) on tungsten-titanium alloy target solder side, aluminum or aluminum alloy layer is formed;
(3) adopt diffusion welding method that tungsten-titanium alloy target is welded on copper alloy backing plate.
2. method according to claim 1, is characterized in that, described tungsten-titanium alloy target is planar targets, and thickness is 1mm ~ 20mm.
3. method according to claim 1, is characterized in that, described copper alloy is ormolu, Jackson's alloy or chromiumcopper.
4. method according to claim 1, is characterized in that, described processing is treated to be carried out blasting treatment at tungsten-titanium alloy target solder side or processes groove; Groove is processed at copper alloy backing plate solder side.
5. method according to claim 4, is characterized in that, the roughness of described blasting treatment is 1 μm ~ 15 μm.
6. method according to claim 1, is characterized in that, the method forming described aluminum or aluminum alloy layer in step (2) is spraying, sputtering, evaporation or directly put into.
7. method according to claim 1, is characterized in that, described aluminum or aluminum alloy layer thickness is 0.01mm ~ 10mm.
8. method according to claim 1, is characterized in that, described diffusion welding method is: adopt high temperature insostatic pressing (HIP), the temperature of welding is 200 DEG C ~ 600 DEG C, pressure 50 ~ 150MPa, temperature retention time 0.5 ~ 10 hour.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410357281.6A CN104259644B (en) | 2014-07-24 | 2014-07-24 | A kind of welding method of tungsten-titanium alloy target |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410357281.6A CN104259644B (en) | 2014-07-24 | 2014-07-24 | A kind of welding method of tungsten-titanium alloy target |
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| Publication Number | Publication Date |
|---|---|
| CN104259644A true CN104259644A (en) | 2015-01-07 |
| CN104259644B CN104259644B (en) | 2016-04-27 |
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| CN201410357281.6A Active CN104259644B (en) | 2014-07-24 | 2014-07-24 | A kind of welding method of tungsten-titanium alloy target |
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Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105296944A (en) * | 2015-10-27 | 2016-02-03 | 有研亿金新材料有限公司 | Target material assembly with antioxidative plating |
| CN106180721A (en) * | 2015-05-08 | 2016-12-07 | 北京有色金属研究总院 | CIGS target material metal layer preparation method |
| CN106702333A (en) * | 2015-07-29 | 2017-05-24 | 宁波江丰电子材料股份有限公司 | Manufacturing method of target material assembly |
| CN107511586A (en) * | 2017-10-09 | 2017-12-26 | 有研亿金新材料有限公司 | A kind of method of laser assisted welding target and backboard |
| CN108000057A (en) * | 2017-10-27 | 2018-05-08 | 包头稀土研究院 | The manufacture method of target material assembly |
| CN111014930A (en) * | 2019-12-23 | 2020-04-17 | 有研亿金新材料有限公司 | Two-step hot isostatic pressing diffusion welding method for tungsten target assembly |
| CN111015090A (en) * | 2019-11-25 | 2020-04-17 | 有研亿金新材料有限公司 | Copper-based target and back plate welding method |
| CN111185659A (en) * | 2020-02-18 | 2020-05-22 | 宁波江丰电子材料股份有限公司 | Diffusion welding method for titanium target and back plate and prepared titanium target assembly |
| CN111378938A (en) * | 2018-12-29 | 2020-07-07 | 宁波江丰电子材料股份有限公司 | Target assembly and manufacturing method thereof |
| CN112059349A (en) * | 2020-08-31 | 2020-12-11 | 宁波江丰电子材料股份有限公司 | Welding method of titanium target and copper back plate |
| TWI791432B (en) * | 2016-04-01 | 2023-02-11 | 美商哈尼威爾國際公司 | Sputtering target assembly having a graded interlayer and methods of making |
| CN116200639A (en) * | 2022-12-30 | 2023-06-02 | 北京安泰六九新材料科技有限公司 | CrW alloy target and preparation method thereof |
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| US6793124B1 (en) * | 2000-10-02 | 2004-09-21 | Nikko Materials Company, Limited | Diffusion-joined target assemly of high-purity cobalt target and copper alloy backing plate and production method therefor |
| CN102554455A (en) * | 2011-12-31 | 2012-07-11 | 宁波江丰电子材料有限公司 | Diffusion welding method for tungsten-titanium alloy target and copper alloy back plate |
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Patent Citations (2)
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| US6793124B1 (en) * | 2000-10-02 | 2004-09-21 | Nikko Materials Company, Limited | Diffusion-joined target assemly of high-purity cobalt target and copper alloy backing plate and production method therefor |
| CN102554455A (en) * | 2011-12-31 | 2012-07-11 | 宁波江丰电子材料有限公司 | Diffusion welding method for tungsten-titanium alloy target and copper alloy back plate |
Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106180721A (en) * | 2015-05-08 | 2016-12-07 | 北京有色金属研究总院 | CIGS target material metal layer preparation method |
| CN106702333A (en) * | 2015-07-29 | 2017-05-24 | 宁波江丰电子材料股份有限公司 | Manufacturing method of target material assembly |
| CN105296944A (en) * | 2015-10-27 | 2016-02-03 | 有研亿金新材料有限公司 | Target material assembly with antioxidative plating |
| TWI791432B (en) * | 2016-04-01 | 2023-02-11 | 美商哈尼威爾國際公司 | Sputtering target assembly having a graded interlayer and methods of making |
| CN107511586A (en) * | 2017-10-09 | 2017-12-26 | 有研亿金新材料有限公司 | A kind of method of laser assisted welding target and backboard |
| CN108000057A (en) * | 2017-10-27 | 2018-05-08 | 包头稀土研究院 | The manufacture method of target material assembly |
| CN111378938A (en) * | 2018-12-29 | 2020-07-07 | 宁波江丰电子材料股份有限公司 | Target assembly and manufacturing method thereof |
| CN111015090A (en) * | 2019-11-25 | 2020-04-17 | 有研亿金新材料有限公司 | Copper-based target and back plate welding method |
| CN111014930B (en) * | 2019-12-23 | 2022-01-18 | 有研亿金新材料有限公司 | Two-step hot isostatic pressing diffusion welding method for tungsten target assembly |
| CN111014930A (en) * | 2019-12-23 | 2020-04-17 | 有研亿金新材料有限公司 | Two-step hot isostatic pressing diffusion welding method for tungsten target assembly |
| CN111185659A (en) * | 2020-02-18 | 2020-05-22 | 宁波江丰电子材料股份有限公司 | Diffusion welding method for titanium target and back plate and prepared titanium target assembly |
| CN112059349A (en) * | 2020-08-31 | 2020-12-11 | 宁波江丰电子材料股份有限公司 | Welding method of titanium target and copper back plate |
| CN116200639A (en) * | 2022-12-30 | 2023-06-02 | 北京安泰六九新材料科技有限公司 | CrW alloy target and preparation method thereof |
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