CN101007396A - Application of polishing head in chemico-mechanical polishing technology and polishing method of chemico-mechanical - Google Patents
Application of polishing head in chemico-mechanical polishing technology and polishing method of chemico-mechanical Download PDFInfo
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- CN101007396A CN101007396A CN 200610006061 CN200610006061A CN101007396A CN 101007396 A CN101007396 A CN 101007396A CN 200610006061 CN200610006061 CN 200610006061 CN 200610006061 A CN200610006061 A CN 200610006061A CN 101007396 A CN101007396 A CN 101007396A
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- rubbing head
- pressure
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Abstract
A polishing head used for chemical mechanical polishing (CMP) process, it includes: a shell; a wafer edge pressure ring locked below the shell; a support backplane which is equipped with a number of pressure zones in non-concentric arrangement, and the support backplane is equipped with a wafer contact surface and a non-wafer contact surface, the wafer contact surface of the support backplane leans against a wafer back side when CMP polishing; and a pneumatic device used for controlling the down pressure applied on the wafer back side in some of the many non-concentric pressure zones independently when CMP polishing.
Description
Technical field
The present invention relates to chemically mechanical polishing (the chemical mechanicalpolishing in the semiconductor technology, be designated hereinafter simply as CMP) field, relate in particular to a kind of rubbing head (carrier head) design of novelty, can in polishing process, obtain the preferable polishing uniformity (uniformity).
Background technology
In making the process of integrated circuit, inevitably need be on a wafer stacked structure of precipitation number layer unlike material, thus, cause the concave plane of wafer surface.Irregular wafer surface will cause some photoetching process problems, for example the depth of focus (depth of focus, DOF) deficiency and image transfer deviation.Therefore, in making the integrated circuit process, just often need be with planarization, CMP technology for example, the in addition irregular surface of planarization wafer.
The CMP technology is that a polished wafer face is pressed on the polishing pad (polishing pad) down, this polished wafer is fixed by a discoid mechanism that is called rubbing head (carrier head), in the polishing stage, rubbing head drives this polished wafer and rotates with a fixed rotating shaft, polishing pad is then with another rotating shaft rotation, then by chemistry or mechanical system is able to the dielectric layer that wafer surface is to be removed or metal level polishes.More general rubbing head is a kind of design that is called unsteady (floating) rubbing head at present, it is to utilize an elastic membrane (flexible membrane) that a wafer support dish or backboard (backing plate) are fixed in pedestal below, in the polishing stage, can utilize gas pressurized on the wafer support dish, impose on the downforce (downforce) of the brilliant back of the body of wafer with average dispersion.
The problem that existing C MP technology is often met is that formation polished lip-deep pattern distribution of wafer and high low head are often also unequal, thus, cause when carrying out the CMP polishing, inhomogeneous on polishing speed on the wafer surface distributes, for example, polishing speed at the pattern density higher position is slower, and then polishing is very fast to dredge the place at pattern density.In addition, the polished material layer on the wafer surface also may present high low uneven thickness phenomenon on one side on one side, and at this moment, existing C MP technology and traditional rubbing head design promptly can't provide the effect that makes wafer surface that preferable planarization be arranged.
Summary of the invention
Main purpose of the present invention provides a kind of rubbing head (carrier head) design and cmp method of improvement, can obtain the preferable polishing uniformity in the CMP polishing process.
According to a preferred embodiment of the invention, the invention provides a kind of rubbing head that is applied to chemically mechanical polishing (CMP) technology, comprising: a housing; One Waffer edge covers ring, is locked in a lower position of this housing; One supporting back board, it has a plurality of pressure areas (pressure zone) that non-concentric circles (non-concentric) is arranged that are, and this supporting back board has a wafer contact-making surface and an amorphous sheet contact-making surface, when wherein carrying out CMP polishing, this wafer contact-making surface of this supporting back board is against living a chip back surface; And a pneumatic means, be used for when carrying out this CMP polishing independently control these a plurality of pressure that are applied to this chip back surface in the non-concentric circles line pressure district that are individually.
According to another preferred embodiment of the invention, the invention provides a kind of cmp method, comprise the steps: at least
(a) wafer is fixed on the rubbing head, wherein this rubbing head includes a pressure apparatus, and it is controlled by a control module, be used for when carrying out CMP polishing, control is applied on the back side of this wafer independently, and each is in the pressure area of non-concentric circles arrangement, individual other pressure;
(b) this rubbing head and a polishing pad are rotated, wherein this rubbing head is to be placed on this polishing pad;
(c) provide a downforce to this wafer; And
(d) material layer on this wafer is polished removal equably.
Major advantage of the present invention is can be when polishing, and rubbing head can provide an instant adjustable downforce by the design of air bag and backboard bottom, therefore can improve the polishing uniformity of wafer surface.
In order to allow above-mentioned and other purpose, feature and the advantage of the present invention can be clearer and more definite understandable, a preferred embodiment cited below particularly, conjunction with figs. elaborates.
Description of drawings
What Fig. 1 illustrated is the generalized section of chemical-mechanical polishing mathing platform of the present invention;
What Fig. 2 illustrated is the cross-sectional view of the rubbing head of the preferred embodiment of the present invention;
Fig. 3 illustrates be the preferred embodiment of the present invention supporting back board on look schematic diagram;
Look schematic diagram on another preferred embodiment supporting back board of the present invention that Fig. 4 illustrates;
What Fig. 5 illustrated is another preferred embodiment rubbing head cross-sectional view of the present invention.
The main element symbol description
50 chemical-mechanical polishing mathing platforms, 52 rubbing heads
54 wafers, 56 polishing pads
60 rotating shafts of 58 polished land
62 rotating shafts, 150 housings
152 Waffer edges cover ring 154 supporting back board
156 brilliant back of the body cushion pad 158 barrier films
Opening around 162 middle openings 164
182 air bag devices, 184 air bag devices
192 pressure responsive element, 194 pressure responsive element
The specific embodiment
See also Fig. 1, what it illustrated is the generalized section of chemical-mechanical polishing mathing platform of the present invention.As shown in Figure 1, chemical-mechanical polishing mathing platform 50 of the present invention includes a rubbing head 52, is used for fixing a wafer 54.Rubbing head 52 is connected to a power transmission shaft and a mechanical switch arm (not shown) usually, and wherein the mechanical switch arm can transmit wafer between different polishing pads.In addition, chemical-mechanical polishing mathing platform 50 also includes a polishing pad 56, and it is to be fixedly installed on the polished land 58.
When carrying out CMP when polishing, rubbing head 52 is to apply a downforce to give wafer 54, and polished of wafer 54 contacted with polishing pad 56.Polishing pad 56 can be the polyurethanes (foamed polyurethane) of foaming or design the irrigation canals and ditches structure that different pattern is arranged that on the material membrane that polyurethanes constituted in addition, polishing pad 56 also may comprise other material.On polishing pad 56, then be distributed with deployed in advance polishing slurries (slurry), provide polishing required polishing agent (abrasive) and other active chemical components, rubbing head 52 then is rotated its rotating shaft 62 and 60 respectively simultaneously with polished land 58, and mode provides needed chemical force of polished wafer surface material layer and mechanical force by this.
See also Fig. 2, what it illustrated is the cross-sectional view of the rubbing head of the preferred embodiment of the present invention.As shown in Figure 2, rubbing head 52 of the present invention includes a housing 150 haply, a Waffer edge covers ring (retaining ring) 152, one discoid supporting back board (disk-shaped backingplate) 154 and one brilliant back of the body cushion pad (backing film) 156.
Wafer 54 is to cover ring 152 by Waffer edge to limit and be fixed in the rubbing head 52.Waffer edge covers ring 152 and is generally the ring-type moulding, can be locked in housing 150 lower position on every side by screw.Waffer edge covers ring 152 and define a pocket zone (pocket area) under housing 150, and its size is used for holding wafer 54 just.In addition, Waffer edge covers a ring inner surface of 152 can interlock wafer 54, skids off from rubbing head 52 bottoms during polishing to avoid wafer 54.
Brilliant back of the body cushion pad 156 is plate-like moulding films, can be constituted by macromolecular material, and its position can be pasted on supporting back board 154 by pressure sensitive glue (pressure sensitiveadhesive) between supporting back board 154 and wafer 54.Brilliant back of the body cushion pad 156 is comparatively responsive for pressure, can cushion the downforce that puts on wafer 54 back sides, and can compensate the small out-of-flatness surface of backboard 154 or chip back surface.
In addition, rubbing head 52 of the present invention also can comprise a barrier film 158, be generally an endless flexible material film (annular ring of a flexible material), the one end is to cover 152 on ring by housing 150 and Waffer edge to clamp, and the other end then can utilize a strangulation ring (clamp ring) to lock above supporting back board 154 with screw.The composition of barrier film 158 can be rubber or artificial rubber (elastomeric-coatedfibric), for example NYLON
TMOr NOMEX
TM, perhaps glass fibre or the like.
Supporting back board 154 can be by harder not easily broken made flat disc of material such as stainless steels, and its size can be bigger a little than wafer 54.When carrying out the CMP polishing, the downforce of rubbing head 52 is the back side that puts on wafer 54 by supporting back board 154, makes downforce and polishing power can be dispersed to wafer surface uniformly, reaches the purpose of uniform polish by this.Supporting back board 154 has a wafer contact-making surface and an amorphous sheet contact-making surface, and when wherein carrying out the CMP polishing, the wafer contact-making surface of supporting back board 154 is against the back side of living wafer 54.
According to a preferred embodiment of the invention, supporting back board 154 has a plurality of pressure areas (pressure zone) that non-concentric circles (non-concentric) is arranged that are, and is defined out by middle opening 162 independently and the opening 164 that is centered around around the middle opening respectively.The a plurality of numbers that are the pressure area that non-concentric circles arranges that had on the supporting back board 154 if greater than 5 then for preferable.
See also Fig. 3 and Fig. 4, wherein look schematic diagram on the supporting back board according to the preferred embodiment of the invention 154 that Fig. 3 illustrates, Fig. 4 illustrates be another preferred embodiment according to the present invention supporting back board 154 on look schematic diagram.As shown in Figure 3, form the pressure area of 6 non-concentric circles altogether in supporting back board 154, wherein middle opening 162 by around opening 164 surrounded.Middle opening 162 is a circular open, and opening 164 then is fan-shaped opening on every side.
As shown in Figure 4, according to another preferred embodiment of the invention, form the pressure area of 9 non-concentric circles altogether in supporting back board 154, wherein middle opening 162 is surrounded by opening 164 on every side equally, and middle opening 162 is pros or rectangular aperture, and opening 164 then is irregular opening on every side.In addition, be formed on the opening design on the supporting back board 154, its number can surpass more than 9, it will be understood by those skilled in the art that the patterns of openings in Fig. 3 and Fig. 4 and distribute only to be illustration.
As shown in Figure 2, according to a preferred embodiment of the invention, rubbing head 52 of the present invention also can include a plurality of air bag devices (pneumatic bladder) 182 and 184, it is placed on the supporting back board 154 corresponding middle opening 162 respectively and on every side in the opening 164, is used for controlling independently the downforce that is applied to wafer 54 back sides in indivedual pressure areas.Above-mentioned a plurality of air bag device 182 and 184 inflation and bleed and to finish by the individual gases supply line that is connected to gas source or pumping.
See also Fig. 5, what it illustrated is the rubbing head cross-sectional view of another preferred embodiment of the present invention.As shown in Figure 5, the rubbing head 52 of another preferred embodiment of the present invention is with rubbing head difference shown in Figure 2, in each non-concentric circles pressure area, be respectively arranged with pressure responsive element 192 and 194 in addition, wherein pressure responsive element 192 is arranged in the middle opening 162, and pressure responsive element 194 is arranged on every side in the opening 164.
According to a preferred embodiment of the invention, pressure responsive element 192 and 194 can be piezoelectric, piezoelectric crystalline, piezoelectric inductor or piezoelectric ceramics inductor etc., for example, and barium titanate (BaTiO
3), AlN, ZnO, lead zirconate titanate (PZT), zirconia, tantalum oxide (Ta
2O
5), tantalates, quartz, tourmaline, Luo De salt, niobates etc.
Another principal character of the present invention is that pressure responsive element 192 and 194 can be detected wafer surface in the CMP polishing process because the pressure that height rises and falls to be produced changes, and signal can be sent back the control module of CMP board, computer for example, control module is immediately controlled the pressure of the above-mentioned a plurality of air bag devices 182 of exporting to of pumping or gas source and 184 again according to the signal of pressure responsive element 192 and 194 feedbacks, change the downforce in the non-concentric circles pressure area by this, so make the polishing of wafer to be controlled accurately, and improve the polishing uniformity, and can adapt to different wafer surface profiles and all can obtain preferable flatness.
The above only is the preferred embodiments of the present invention, and all equalizations of doing according to claim of the present invention change and modify, and all should belong to covering scope of the present invention.
Claims (14)
1. rubbing head that is applied to CMP process comprises:
One housing;
One Waffer edge covers ring, is locked in a lower position of this housing;
One supporting back board, it has a plurality of pressure areas that non-concentric circles is arranged that are, and this supporting back board has a wafer contact-making surface and an amorphous sheet contact-making surface, and when wherein carrying out a chemically mechanical polishing, this wafer contact-making surface of this supporting back board is against living a chip back surface; And
One pressure apparatus is used for when carrying out this chemically mechanical polishing, and independent control is these a plurality of being in the non-concentric circles line pressure district individually, are applied to the pressure of this chip back surface.
2. the rubbing head that is applied to CMP process as claimed in claim 1, wherein this rubbing head also comprises a brilliant back of the body cushion pad, is located between this chip back surface and this supporting back board.
3. the rubbing head that is applied to CMP process as claimed in claim 1, wherein this a plurality of to be pressure areas that non-concentric circles arranges be that a plurality of separate openings by this supporting back board is defined out, this a plurality of separate openings opening on every side of comprising a middle opening and centering on this middle opening wherein.
4. the rubbing head that is applied to CMP process as claimed in claim 1, wherein this rubbing head also comprises a barrier film.
5. the rubbing head that is applied to CMP process as claimed in claim 4, wherein this barrier film is an endless flexible material film.
6. the rubbing head that is applied to CMP process as claimed in claim 1, wherein this rubbing head also comprises a pressure responsive element, is located at respectively this a plurality of being in the pressure area that non-concentric circles arranges.
7. the rubbing head that is applied to CMP process as claimed in claim 6, wherein this pressure responsive element comprises piezoelectric, piezoelectric crystalline, piezoelectric inductor or piezoelectric ceramics inductor.
8. the rubbing head that is applied to CMP process as claimed in claim 6, wherein this pressure responsive element comprises barium titanate, AlN, ZnO, lead zirconate titanate, zirconia, tantalum oxide, tantalates, quartz, tourmaline, Luo De salt or niobates.
9. the rubbing head that is applied to CMP process as claimed in claim 6, wherein this pressure responsive element is detected the surface of this wafer because the pressure that is produced that just rises and falls changes in this chemically mechanical polishing, and a feedback signal can be sent back a control module.
10. cmp method comprises:
One wafer is fixed on the rubbing head, and wherein this rubbing head comprises a pressure apparatus, and it is controlled by a control module, be used for when carrying out a chemically mechanical polishing, control is applied on the back side of this wafer independently, and each is in the pressure area of non-concentric circles arrangement, individual other pressure;
This rubbing head and a polishing pad are rotated, and wherein this rubbing head is to be placed on this polishing pad;
Provide a downforce to this wafer; And
Material layer on this wafer is polished removal equably.
11. cmp method as claimed in claim 10, wherein this method also comprises provides at least one pressure responsive element, is located in respectively this pressure area that is non-concentric circles arrangement on this wafer.
12. cmp method as claimed in claim 11, wherein this pressure responsive element comprises piezoelectric, piezoelectric crystalline, piezoelectric inductor or piezoelectric ceramics inductor.
13. cmp method as claimed in claim 11, wherein this pressure responsive element comprises barium titanate, AlN, ZnO, lead zirconate titanate, zirconia, tantalum oxide, tantalates, quartz, tourmaline, Luo De salt or niobates.
14. cmp method as claimed in claim 11, wherein this pressure responsive element is detected the surface of this wafer because the pressure that is produced that just rises and falls changes in this chemically mechanical polishing, and a feedback signal can be sent back a control module.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200610006061 CN101007396A (en) | 2006-01-24 | 2006-01-24 | Application of polishing head in chemico-mechanical polishing technology and polishing method of chemico-mechanical |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200610006061 CN101007396A (en) | 2006-01-24 | 2006-01-24 | Application of polishing head in chemico-mechanical polishing technology and polishing method of chemico-mechanical |
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|---|---|
| CN101007396A true CN101007396A (en) | 2007-08-01 |
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|---|---|---|---|
| CN 200610006061 Pending CN101007396A (en) | 2006-01-24 | 2006-01-24 | Application of polishing head in chemico-mechanical polishing technology and polishing method of chemico-mechanical |
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Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101417407B (en) * | 2007-10-25 | 2011-10-05 | 中芯国际集成电路制造(上海)有限公司 | Chemical mechanical grinding method |
| CN103100966A (en) * | 2011-11-11 | 2013-05-15 | 中芯国际集成电路制造(上海)有限公司 | Chemical mechanical lapping device and system |
| JP2014039985A (en) * | 2012-08-23 | 2014-03-06 | Disco Abrasive Syst Ltd | Grinding device |
| CN105619240A (en) * | 2016-01-21 | 2016-06-01 | 苏州新美光纳米科技有限公司 | Chip vacuum adsorption template and method |
| JP2017064801A (en) * | 2015-09-28 | 2017-04-06 | 株式会社荏原製作所 | Polishing method and polishing device |
| CN107195547A (en) * | 2017-05-05 | 2017-09-22 | 天津华海清科机电科技有限公司 | In the method for improved wire flatness of wafer surface |
| CN107344327A (en) * | 2017-05-05 | 2017-11-14 | 清华大学 | In the method for improved wire flatness of wafer surface |
| CN108098567A (en) * | 2017-12-14 | 2018-06-01 | 苏州新美光纳米科技有限公司 | Polishing pressure buffer pad, burnishing device and glossing |
| CN111300258A (en) * | 2018-12-10 | 2020-06-19 | 三星电子株式会社 | Chemical mechanical polishing apparatus for controlling polishing uniformity |
| CN111941269A (en) * | 2013-12-11 | 2020-11-17 | 台湾积体电路制造股份有限公司 | Chemical mechanical polishing system and method of polishing substrate |
| CN112605847A (en) * | 2020-11-23 | 2021-04-06 | 福建晶安光电有限公司 | Improved wafer substrate polishing method and apparatus |
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2006
- 2006-01-24 CN CN 200610006061 patent/CN101007396A/en active Pending
Cited By (18)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101417407B (en) * | 2007-10-25 | 2011-10-05 | 中芯国际集成电路制造(上海)有限公司 | Chemical mechanical grinding method |
| CN103100966A (en) * | 2011-11-11 | 2013-05-15 | 中芯国际集成电路制造(上海)有限公司 | Chemical mechanical lapping device and system |
| JP2014039985A (en) * | 2012-08-23 | 2014-03-06 | Disco Abrasive Syst Ltd | Grinding device |
| CN111941269A (en) * | 2013-12-11 | 2020-11-17 | 台湾积体电路制造股份有限公司 | Chemical mechanical polishing system and method of polishing substrate |
| US11407083B2 (en) | 2013-12-11 | 2022-08-09 | Taiwan Semiconductor Manufacturing Co., Ltd. | Polishing head, chemical-mechanical polishing system and method for polishing substrate |
| CN111941269B (en) * | 2013-12-11 | 2022-07-22 | 台湾积体电路制造股份有限公司 | Chemical mechanical polishing system and method of polishing substrate |
| JP2017064801A (en) * | 2015-09-28 | 2017-04-06 | 株式会社荏原製作所 | Polishing method and polishing device |
| CN108025419A (en) * | 2015-09-28 | 2018-05-11 | 株式会社荏原制作所 | Ginding process and lapping device |
| KR20180061240A (en) * | 2015-09-28 | 2018-06-07 | 가부시키가이샤 에바라 세이사꾸쇼 | Polishing method and polishing apparatus |
| US10569381B2 (en) | 2015-09-28 | 2020-02-25 | Ebara Corporation | Polishing method and polishing apparatus |
| KR102530554B1 (en) | 2015-09-28 | 2023-05-10 | 가부시키가이샤 에바라 세이사꾸쇼 | Grinding method and polishing device |
| CN105619240A (en) * | 2016-01-21 | 2016-06-01 | 苏州新美光纳米科技有限公司 | Chip vacuum adsorption template and method |
| CN107344327A (en) * | 2017-05-05 | 2017-11-14 | 清华大学 | In the method for improved wire flatness of wafer surface |
| CN107195547A (en) * | 2017-05-05 | 2017-09-22 | 天津华海清科机电科技有限公司 | In the method for improved wire flatness of wafer surface |
| CN108098567A (en) * | 2017-12-14 | 2018-06-01 | 苏州新美光纳米科技有限公司 | Polishing pressure buffer pad, burnishing device and glossing |
| CN111300258A (en) * | 2018-12-10 | 2020-06-19 | 三星电子株式会社 | Chemical mechanical polishing apparatus for controlling polishing uniformity |
| CN112605847A (en) * | 2020-11-23 | 2021-04-06 | 福建晶安光电有限公司 | Improved wafer substrate polishing method and apparatus |
| CN112605847B (en) * | 2020-11-23 | 2022-04-19 | 福建晶安光电有限公司 | Improved wafer substrate polishing method and apparatus |
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