CN109940517A - A kind of lapping liquid distribution arm and CMP apparatus - Google Patents
A kind of lapping liquid distribution arm and CMP apparatus Download PDFInfo
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- CN109940517A CN109940517A CN201910250307.XA CN201910250307A CN109940517A CN 109940517 A CN109940517 A CN 109940517A CN 201910250307 A CN201910250307 A CN 201910250307A CN 109940517 A CN109940517 A CN 109940517A
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- lapping liquid
- nozzle
- baffle
- distribution arm
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Abstract
This application involves a kind of lapping liquid distribution arm and CMP apparatus.Distribution arm for distributing lapping liquid includes mechanical arm, and the mechanical arm can be moved to any required position;Be configured for the nozzle of conveying lapping liquid, fixedly or adjustable angle the lower section of mechanical arm is set;Be configured for buffering the baffle of the lapping liquid of the nozzle discharge, fixedly or adjustable angle the lower section of the nozzle is obliquely run out to from the connector for connecting the baffle and the mechanical arm.In addition, the application further relate to include the distribution arm CMP apparatus.Lapping liquid distribution arm of the invention can make to be evenly distributed wait spread over the lapping liquid on grinding table top, while also improve the utilization rate of lapping liquid, improve grinding quality.
Description
Technical field
The present invention relates to field of semiconductor manufacture, relate more specifically to Semiconductor Chemistry machinery planarization device.
Background technique
In semiconductor fabrication, CMP (chemical-mechanical planarization) is particularly significant for such as photoetching of its subsequent step, it can
To remove the impurity material that semiconductor device surface is not intended to retain, to improve the yield rate of device.
In Semiconductor Chemistry mechanical grinding process, usually using the lapping liquid comprising grinding agent to promote to be changed simultaneously
And mechanical lapping.Lapping liquid is provided by lapping liquid distribution arm onto the grinding pad of grinding plate.During the grinding process, with grinding
The rotation of platform is polished, lapping liquid is uniformly distributed between semiconductor wafer and grinding pad to be planarized, to realize to chip
Uniform grinding.Therefore, the uniformity of lapping liquid distribution is most important for the grinding of semiconductor wafer.
In conventional lapping liquid distribution arm, due to using the slurry nozzle of circular cross-section (as shown in Figure 1), so that
It when lapping liquid flows to the surface of grinding table top (platen) of rotation, cannot sprawl rapidly, but be formed and nozzle cross-section width
Comparable relatively narrow liquid stream.Even if such relatively narrow liquid stream is still not easy Quick uniform dispersion (such as after touching semiconductor wafer
Shown in Fig. 3).This phenomenon requires nozzle to provide the grinding flow quantity much larger than usage amount to its flowing on grinding pad
And whole wafer surface is covered, but cause the great waste of lapping liquid in this way.
Patent application WO 2010051284 improves lapping liquid on grinding plate surface using distributed lapping liquid distribution arm
The uniformity of upper distribution, wherein multiple distributed nozzles are provided in lapping liquid distribution arm.However, the distribution arm configuration
Complexity needs flow control element to carry out accurate control to improve the lapping liquid uniformity being distributed on platform surface, therefore operates multiple
Miscellaneous and higher cost.
Chinese patent application No.201310211055.2 discloses a kind of lapping liquid distribution arm, and which employs one kind to include
The distribution arm of two mechanical arms connected by bearing, the two mechanical arms can be put by the control of control module respectively
It is dynamic, to realize the control to lapping liquid sprinkling direction.The distribution arm configuration is also more complex, at high cost and be unfavorable for safeguarding.
Therefore, it is necessary to a kind of structure is simple, low cost lapping liquid distribution arm realizes that lapping liquid is being ground easily to operate
The Quick uniform of table top, while can be reduced the amount of the lapping liquid of waste.
Summary of the invention
To solve the above problems, the present invention provides a kind of simple lapping liquid distribution arms of structure, to provide improved grind
Grinding fluid utilization rate and quick distributing homogeneity.
To reach this purpose, first aspect present invention provides a kind of for distributing the distribution arm of lapping liquid, which is characterized in that
The distribution arm includes:
Mechanical arm, the mechanical arm can be moved to any required position;
Be configured for the nozzle of conveying lapping liquid, fixedly or adjustable angle the lower section of mechanical arm is set;
Be configured for buffering the baffle of the lapping liquid of the nozzle discharge, fixedly or adjustable angle from for connecting
The lower section of the nozzle is obliquely run out on the connector of the baffle and the mechanical arm.
According to a kind of embodiment, the central axis of the nozzle and the angle of plumb line are 0 °~30 °, preferably 0 °.
According to a kind of embodiment, the length-width ratio of the nozzle is 5~20, preferably 8~12.
According to a kind of embodiment, the exit cross-section shape of the nozzle is rectangle or ellipse.
In addition, according to a kind of embodiment, the straight line parallel where the long axis of the outlet of nozzle of the invention is in institute
State the plane where baffle.
According to a kind of embodiment, the angle between the plane and plumb line of the baffle is 30 °~60 °.Preferably
45°。
According to a kind of embodiment, the width of the baffle is the 120%~150% of the nozzle length.
According to a kind of embodiment, the material of the baffle is selected from PFA, FEP, PTFE, PMMA, glass and resin, preferably
Selected from PFA and PTFE.
According to a kind of embodiment, the connection type of the connector and the baffle or the mechanical arm be selected from welding,
Hot-melt adhesive paste, threaded connection, sucker connection, riveting and bonding, are preferably threadedly coupled.
According to the second aspect of the invention, a kind of CMP apparatus is additionally provided, described device includes grinding
Table top, at least one bistrique and the distribution arm described according to a first aspect of the present invention.It is distributed by using lapping liquid of the present invention
Arm can make quickly and evenly to be distributed wait spread over the lapping liquid on grinding table top, to improve the grinding quality of chip, together
When also improve the utilization rate of lapping liquid, reduce the waste of lapping liquid.
Detailed description of the invention
Fig. 1 is the front view of the lapping liquid distribution arm of the prior art;
Fig. 2 is the right view of the lapping liquid distribution arm of the prior art;
Fig. 3 is the schematic diagram of the lapping liquid distribution arm of the prior art at runtime;
Fig. 4 is the front view of lapping liquid distribution arm of the invention;
Fig. 5 is the side view of lapping liquid distribution arm of the invention;
Fig. 6 is the schematic diagram of lapping liquid distribution arm of the invention at runtime;With
Fig. 7 is the front view of the lapping liquid distribution arm of one embodiment of the present invention.
Specific embodiment
In order to elaborate Spirit Essence of the invention, given below in conjunction with the specific embodiment of attached drawing through the invention
With explanation.It should be understood that following specific embodiments are merely to illustrate the present invention, and and it is not meant to limit the scope of the invention.
Which show respectively the front views and right view of the lapping liquid distribution arm of the prior art combined with Figure 1 and Figure 2,.?
Shown in Fig. 1 and 2, the nozzle 112 of prior art lapping liquid distribution arm 10 is round nozzle, i.e., the section of jet expansion is circle
Shape.Further combined with Fig. 3, the schematic diagram of the lapping liquid distribution arm of the prior art at runtime is shown.Due to grinding
When the nozzle 112 of liquid distribution arm 10 works, the sub-thread lapping liquid 114 of round nozzle (112) is in pencil, and the lapping liquid is with grinding
Platform 101 turns to when silicon wafer 102 contacts that there is still a need for certain times to sprawl, and the fast speed that grinding plate 101 rotates, and grinds
Grinding fluid 114 is difficult comprehensive drawout in a short time, therefore the lapping liquid 114 is ground when contacting by grinding table top and silicon wafer
Grinding fluid is likely to not sprawl uniformly also, to make the uniformity of grinding be unable to get guarantee, so that it is bad to generate grinding effect
Problem.
To guarantee to have sprawled lapping liquid on entire grinding pad, usually accelerate to grind by increasing the flow of lapping liquid
The spreading rate of liquid, but to bring lapping liquid producing level low for excessive lapping liquid, wastes serious situation.
In order to overcome these deficiencies, current inventor provides a kind of improved lapping liquid distribution arms.
As shown in figures 4-6, the structure and operation schematic diagram of lapping liquid distribution arm of the invention are respectively illustrated.Wherein Fig. 4
For the front view of lapping liquid distribution arm of the invention;Fig. 5 is the right view of lapping liquid distribution arm of the invention;Fig. 6 is the present invention
Lapping liquid distribution arm schematic diagram at runtime.
Referring to fig. 4 with 5, lapping liquid distribution arm 20 of the invention includes mechanical arm 210, nozzle 212, baffle 214 and connection
Part 215.
Mechanical arm 210 is used to support nozzle 212 and the baffle 214 that is connected on connector 215, and can arbitrarily move so as to
Nozzle 212 and baffle 215 is set to be located at the suitable position above grinding table top.
Nozzle 212 of the invention is mounted below 210 end of mechanical arm, for conveying lapping liquid to grinding table top.Spray
The outlet of mouth 212 is defined as its long axis on the direction for the longest distance having, fixed on the direction with the shortest distance
Justice is its short axle, and the outlet is in " length " that the distance of the long axis direction is outlet, in the short-axis direction
Distance be outlet " width ".The length-width ratio of the outlet of nozzle 212 of the invention can be 5~20, preferably 8
~12, more preferably 10.
It should be noted that the length of the outlet of the nozzle 212 of meaning shown in attached drawing and wide only schematical size,
Actual size and its proportionate relationship are not represented.
According to a kind of specific embodiment, the long axis and short axle of the outlet of nozzle 212 are mutually perpendicular to.
Therefore, the cross sectional shape of nozzle of the invention is flat.The outlet of nozzle 212 of the invention can be square
Shape can also be ellipse, be also possible to the irregular shapes such as any other flat pattern, such as zigzag.
It can be according to composite factors such as the physical property such as the flow for grinding the revolving speed of table top, the revolving speed of silicon wafer to be ground, lapping liquid
To determine the length and width of nozzle throat area when cross sectional shape.
The center of gravity of the outlet of nozzle of the present invention is defined by mathematical way known in the art:
Assuming that the jet expansion cross-section, in x/y plane, the arbitrary point in section is (xi,yi), then its center of gravity is
(x0,y0), wherein
Wherein, A=∫ ∫ dxdy, wherein A is the area of jet area.
The central axis of the outlet of the nozzle is defined as the center of gravity across the section, perpendicular to the section
Normal.
It, can be to avoid the inventors discovered that when using the outlet of nozzle as with the flat pattern of above-mentioned length-width ratio
Lapping liquid forms pencil when being discharged from nozzle, i.e. the nozzle of flat pattern can make lapping liquid when being discharged with wider stream forms row
Out, therefore shortening lapping liquid sprawls the time on grinding table top, to make lapping liquid when turning to silicon wafer with grinding table top
It has reached and preferably sprawls state.
The central axis of the nozzle 212 of lapping liquid distribution arm 20 of the invention can be fixed relative to grinding table top 201
Or it is adjustable.The central axis of nozzle of the invention can be vertical, be also possible to inclined, such as the central axis of nozzle 212
It can be 0 °~30 ° with the angle of vertical line of grinding table top 201, with reference to Fig. 7, the central axis of nozzle 212 be shown and grinds
The case where angle α for grinding the vertical line of table top 201 is 30 °.
Preferably, angle is 0 °~10 °, more preferably 0 °, i.e. nozzle is preferably towards being substantially perpendicular to grinding table
Downwards.With reference to Fig. 4, the angle α of the central axis of nozzle 212 and the vertical line of grinding table top 201 is shown as 0 ° of feelings
Condition.
In lapping liquid distribution arm 20 of the invention, it is provided with the baffle for buffering the lapping liquid by nozzle discharge
214.Baffle 214 is mounted on nozzle lower part in such a way that its bottom edge is parallel to grinding table top 201, to grind to what is be discharged by nozzle
Grinding fluid plays the role of buffering.
As shown in figures 4-6, all lapping liquids by nozzle discharge impact the lower surface of baffle 214, and along baffle
214 surface flows on grinding table top 201.Therefore, lapping liquid 216 impacts at plate washer lower part for example, at least 1/5th, excellent
At choosing at least one third;
Baffle 214 can be the baffle of arbitrary shape, for example, rectangle, triangle, trapezoidal or irregular shape etc., as long as
The bottom edge of baffle is linear.
According to a kind of embodiment, the straight line parallel where the long axis of the outlet of nozzle of the invention is in the baffle
The plane at place.
The bottom edge length of the baffle 214 is longer than the length of the outlet of nozzle, so that lapping liquid 216 is in baffle
It is sprawled in advance on 214.And baffle 214 and the width of 216 contact position of lapping liquid are than grinding the width of liquid stream (namely substantially
The width of top nozzle) it is wider, so that lapping liquid can be sprawled in advance before falling on table top 210.According to a kind of embodiment, baffle
214 bottom edge length is about the 120%~150% of the length of nozzle 212.
For convenient for manufacture, fixed and positioned, baffle of the invention is rectangle, but not limited to this.Those skilled in the art can
To determine the shape of baffle according to factors such as the areas of the width of nozzle, lapping liquid to be sprawled.
Baffle 214 is obliquely run out under the nozzle from one end of the connector 215 by connector 215
Side.The other end of connector 215 is then connect with the end of lapping liquid distribution arm 210.As shown in figure 4, baffle-panels 214 and grinding table
The vertical line in face 201 has certain angle.Angle β is 30 °~60 °, preferably 45 °.The material of production baffle can be selected from
PFA (copolymer of perfluoro propyl perfluoroalkyl vinyl ether and polytetrafluoroethylene (PTFE)), FEP (phosphoenolpyruvate), PTFE (poly- four
Vinyl fluoride), PMMA (polymethyl methacrylate), glass and resin, but not limited to this.Preferably, the material of baffle 214 is
PFA or PTFE.
Connector 215 can be identical with the connection type of mechanical arm 210 with the connection type of baffle 214 and connector 215,
It can also be different.For example, connector 215 can by such as welding, hot-melt adhesive paste, threaded connection, sucker connection, riveting, bonding
Deng connection type be connected respectively with baffle 214 and mechanical arm 210, so that connector 215 be made to play the work of fixed baffle 214
With.Those skilled in the art can be according to factors such as the shape of baffle, material, accurate positionings to be placed (i.e. position and angle)
Select its connection type.
Preferably, baffle 214 is connected with the mode that mechanical arm 210 is connected through a screw thread with connector 215.
Baffle of the invention can buffer the lapping liquid being discharged by nozzle, and lapping liquid is made to drop down onto grinding with planar more evenly
On table top.Meanwhile the lapping liquid dropped down on grinding table top 201 is contacted with bigger area with silicon wafer.
Preferably, by selecting the length-width ratio of nozzle and shape, gradient and the bottom edge length of baffle, make to drop down onto and grind
The width of initially sprawling of lapping liquid on mill table top 201 is at least the 30%, preferably at least 50% of brilliant diameter of a circle to be ground, more
It is preferred that 70%~110%.
The working condition of lapping liquid distribution arm of the invention is further illustrated below according to Fig. 6.
When lapping liquid distribution arm 20 is in predeterminated position, the lapping liquid 216 being discharged by nozzle 212 is buffered through baffle 214
After drop down onto grinding table top 201 on, due to grinding table top 201 be rotation, drop down onto grinding 201 surface of table top lapping liquid
214 as the table top of rotation is in horn-like drawout.Then, lapping liquid 216 is contacted with chip 202.Hereafter, chip 202 passes through
Bistrique (not shown) is applied downward pressure, and under the collective effect of lapping liquid 216 and pressure, silicon wafer 202 carries out chemical machine
Tool planarization process.
Lapping liquid distribution arm of the invention by setting flat burner and baffle, the collective effect of the two make lapping liquid with
It more evenly and is in improve grinding quality while reducing and wasting lapping liquid with grinding deck contact more in large area.
The present invention also provides a kind of CMP apparatus, which includes the foregoing present invention for distributing
Distribution arm, grinding table top and at least one bistrique of lapping liquid.
The foregoing is merely some embodiments of the invention, are not intended to limit the scope of the invention, it is all
Under inventive concept of the invention, made equivalent transformation or modification, or directly/to be used in other related technical areas equal indirectly
It is included within the scope of the present invention.
Claims (14)
1. a kind of for distributing the distribution arm of lapping liquid, which is characterized in that the distribution arm includes:
Mechanical arm, the mechanical arm can be moved to any required position;
Be configured for the nozzle of conveying lapping liquid, fixedly or adjustable angle the lower section of mechanical arm is set;
Be configured for buffering the baffle of the lapping liquid of the nozzle discharge, fixedly or adjustable angle from described for connecting
The lower section of the nozzle is obliquely run out on the connector of baffle and the mechanical arm.
2. distribution arm according to claim 1, wherein the central axis of the nozzle and the angle of plumb line are 0 °~30 °.
3. distribution arm according to claim 2, wherein the central axis of the nozzle and the angle of plumb line are 0 °.
4. distribution arm according to claim 1, wherein the length-width ratio of the exit cross-section of the nozzle is 5~20.
5. distribution arm according to claim 4, wherein the length-width ratio of the exit cross-section of the nozzle is 8~12.
6. distribution arm according to claim 4 or 5, wherein the exit cross-section shape of the nozzle is rectangle or ellipse
Shape.
7. distribution arm according to claim 1, wherein the angle between the plane and plumb line of the baffle is 30 °~
60°。
8. distribution arm according to claim 7, wherein the angle between the plane and plumb line of the baffle is 45 °.
9. distribution arm according to claim 1, wherein the width of the baffle be the nozzle length 120%~
150%.
10. distribution arm according to claim 1, wherein the material of the baffle is selected from PFA, FEP, PTFE, PMMA, glass
Glass and resin.
11. distribution arm according to claim 10, wherein the material of the baffle is selected from PFA and PTFE.
12. distribution arm according to claim 1, wherein the connector and the baffle and with the mechanical arm
Connection type is respectively selected from welding, hot-melt adhesive paste, threaded connection, sucker connection, riveting and bonding.
13. distribution arm according to claim 12, wherein the connector and the baffle and with the mechanical arm
Connection type is to be threadedly coupled.
14. a kind of CMP apparatus, described device includes grinding table top, at least one bistrique and is wanted according to right
Distribution arm described in asking 1~13.
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Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
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CN116000821A (en) * | 2023-03-24 | 2023-04-25 | 长鑫存储技术有限公司 | Nozzle and chemical mechanical polishing device |
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CN103846777A (en) * | 2012-11-29 | 2014-06-11 | 盛美半导体设备(上海)有限公司 | Chemical mechanical grinding device and method |
CN104175228A (en) * | 2014-08-08 | 2014-12-03 | 北京迪蒙吉意超硬材料技术有限公司 | Automatic grinded material supplying device and supplying method used for plane grinding equipment |
CN207823279U (en) * | 2018-01-02 | 2018-09-07 | 日照华泰纸业有限公司 | A kind of black liquor atomizing lance |
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CN201841472U (en) * | 2010-07-20 | 2011-05-25 | 中芯国际集成电路制造(上海)有限公司 | Grinding fluid arm and chemical mechanical grinding equipment |
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CN103846777A (en) * | 2012-11-29 | 2014-06-11 | 盛美半导体设备(上海)有限公司 | Chemical mechanical grinding device and method |
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CN116000821A (en) * | 2023-03-24 | 2023-04-25 | 长鑫存储技术有限公司 | Nozzle and chemical mechanical polishing device |
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