CN102133731B - Pressure control system for plurality of chambers of CMP (chemical mechanical polishing) head - Google Patents
Pressure control system for plurality of chambers of CMP (chemical mechanical polishing) head Download PDFInfo
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- CN102133731B CN102133731B CN201110002122A CN201110002122A CN102133731B CN 102133731 B CN102133731 B CN 102133731B CN 201110002122 A CN201110002122 A CN 201110002122A CN 201110002122 A CN201110002122 A CN 201110002122A CN 102133731 B CN102133731 B CN 102133731B
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Abstract
一种用于CMP抛光头多腔室的压力控制系统，属于半导体制造技术领域，其特征在于包括压力源、控制阀组、压力传感器、CPU、数模以及模数转换电路等。该控制系统通过对各支路的压力与流量控制实现对远端各腔室的压力控制。控制阀组每条支路由正压与负压两个通道和一个双向过滤器组成。正压通道由与压力源依次相连的减压阀、正压气囊、电控比例阀、正负压开关阀组构成，其中各正压通道共用同一减压阀以及正压气囊。负压通道由与压力源依次相连的真空开关阀、真空发生器、真空气囊、真空调压阀和正负压开关阀组构成，其中各负压通道共用同一真空开关阀、真空发生器以及真空气囊。正负压开关阀组输出连接过滤器。压力传感器将采集到的各腔室压力经A/D转换电路送至CPU。
A multi-chamber pressure control system for a CMP polishing head belongs to the technical field of semiconductor manufacturing, and is characterized in that it includes a pressure source, a control valve group, a pressure sensor, a CPU, a digital-analog and an analog-to-digital conversion circuit, and the like. The control system realizes the pressure control of each chamber at the far end by controlling the pressure and flow of each branch. Each branch of the control valve group is composed of positive pressure and negative pressure channels and a two-way filter. The positive pressure channel is composed of a pressure reducing valve, a positive pressure airbag, an electronically controlled proportional valve, and a positive and negative pressure switch valve group connected in sequence to the pressure source, wherein each positive pressure channel shares the same pressure reducing valve and positive pressure airbag. The negative pressure channel is composed of a vacuum switching valve, a vacuum generator, a vacuum air bag, a vacuum air-conditioning valve and a positive and negative pressure switching valve group connected in sequence to the pressure source, and each negative pressure channel shares the same vacuum switching valve, vacuum generator and vacuum air bag . The output of the positive and negative pressure switching valve group is connected to the filter. The pressure sensor sends the collected pressure of each chamber to the CPU through the A/D conversion circuit.
Description
Technical field
The present invention relates to the pneumatic control system in the semiconductor manufacturing facility, particularly a kind of chemically mechanical polishing (Chemical Mechanical Polishing, CMP) malleation of rubbing head and vacuum control system of being used for.
Background technology
Current, CMP is the otherwise effective technique of wafer overall situation planarization in the semiconductor fabrication process.Throw in the copper field at CMP, rubbing head clamping silicon chip will wait to throw the polishing disk that the copper laminar surface is pressed to rotation, realize that through polishing pad friction on the polishing disk and polishing fluid corrosion the copper layer removes fast and effectively.Wherein, rubbing head can be realized the overall dynamic adjustments to silicon wafer polishing pressure through each annulus chamber pressure of the control silicon chip back side.
The rubbing head internal chamber is equivalent to a plurality of airtight chamber, and extruding can pushed or not have to inflatable and contraction mutually between the chamber.Coupling between the chamber mainly contains three kinds of situation: a kind of is the volume coupling, i.e. extruding between each chamber or contraction cause the variation of cavity volume; A kind of is source of the gas input coupling, causes source of the gas moment air supply pressure fluctuation when each chamber pressurizes simultaneously; At last a kind of is vacuum output coupling, and during the vacuum action simultaneously of multi-cavity chamber, the variation of a certain chamber vacuum (such as leaking gas) causes other chamber vacuum and changes.For the common way that solves of the situation of volume coupling is to change ways such as structural design or software compensation; And source of the gas input coupling and vacuum output coupling can realize through changing the design of gas circuit control structure.
In addition, the pressure sensitive unit in this control system is used to gather the real-time pressure of chamber, feeds back to the control system subsequently and constitutes the control of full cut-off ring.Yet receive the restriction of structure, the installation site of this sensing unit usually can not be positioned over the rubbing head chamber interior, but is placed in the pneumatic control system exit.
Summary of the invention
The object of the present invention is to provide a kind of control pressurer system of the CMP of being used for rubbing head.It is characterized in that containing:
As source of the gas, control valve group, pressure sensor, A/D change-over circuit, D/A change-over circuit and the CPU of pressure source, wherein:
Total N of pressure sensor; N >=1; Gather N same in a far-end rubbing head chamber pressure respectively; Be input to each chamber pressure that collects among the CPU through an A/D change-over circuit with same N passage, the swivel joint of said N chamber on a wherein said N pressure sensor and chemically mechanical polishing (CMP) equipment links to each other
The control valve group; Total N bar branch road; Each branch road correspondence is connecting a described chamber, and the input of said every branch road links to each other with pressure source, and the output of every branch road links to each other with input corresponding to the said chamber of this branch road; Every route malleation passage, negative pressure channel and a dual flow filter are formed, wherein:
Positive pressure passageway; Pressure-reducing valve, malleation air bag, electronically controlled proportional valve and positive negative pressure switch valve group by series connection successively constitute; The input of said pressure-reducing valve links to each other with the output of said pressure source, wherein shared same pressure-reducing valve of the positive pressure passageway of all branch roads and same malleation air bag
Negative pressure channel; Constitute by the vacuum switch valve, vacuum generator, negative pressure gasbag, vacuum regulating valve of the normally open of series connection successively and with the shared positive negative pressure switch valve group of said positive pressure passageway; The input of said vacuum switch valve links to each other with the output of described pressure source; The wherein shared same vacuum switch valve of the negative pressure channel of all branch roads, vacuum generator and same negative pressure gasbag
The output of described positive negative pressure switch valve group links to each other with the input of a dual flow filter, and the output of this dual flow filter links to each other with said chamber on the corresponding branch road,
Described positive negative pressure switch valve group is by a 3-position-3-way valve, or two two-way valves parallel with one another, or a two-position three-way valve and a two-way valve composition of series connection each other,
CPU; For each said chamber is set a chamber pressure value; Simultaneously; Set the electronically controlled proportional valve of a differential pressure signal output in said positive pressure passageway and export said setting chamber pressure and the difference of surveying chamber pressure, difference is greater than zero, and expression continues pressurization to said chamber; Difference is less than zero; Expression also is provided with said chamber depressurization: the switch-over control signal output simultaneously with the pulldown start-up control signal input part of the vacuum switch valve of said negative pressure channel and with the linking to each other of described positive negative pressure switch valve group by required running status switch-over control signal input, between startup pulldown process and chamber pressure regulation process, switch; The differential pressure signal of said differential pressure output output outputs to the control signal input of electronically controlled proportional valve in the said positive pressure passageway after through the D/A change-over circuit, and the air pressure after the regulation and control is sent to the chamber of correspondence after said switch-over control signal control is down via said positive negative pressure switch valve group, dual flow filter; Said pulldown start-up control signal is opened the vacuum switch valve output of said negative pressure channel, through the vacuum regulating valve pressure regulation after said dual flow filter is sent to corresponding chamber, under off-position, described positive negative pressure switch valve group tangential negative pressure channel.
The control pressurer system of a kind of CMP of being used for rubbing head multi-cavity of the present invention chamber has the following advantages and good effect:
Vacuum leak caused silicon chip to come off when 1, system can avoid owing to system's accident power-off.
2, effectively overcome the influence of source of the gas input coupling and vacuum output coupling.
3, effectively improve because the sensing accuracy error that the sensing unit riding position is brought.
4, because the interpolation of malleation air bag and negative pressure gasbag not only eliminated the influence of coupling, and what is more important is saved cost.
Description of drawings
Fig. 1 is rubbing head multi-cavity chamber pressure control system global structure sketch map of the present invention, L1, and L2 ... Ln representes to lead to every branch road of chamber; DO representes the digital quantity output signal of CPU output;
Fig. 2 controls the part detailed structure sketch map of system, P for Fig. 1
1... P
nRepresent to be sent in the positive pressure passageway branch road of positive negative pressure switch valve group, V
1... V
nBe sent to the branch road of positive negative pressure switch valve group in the expression negative pressure channel; Δ P represents the difference of setup pressure value and observed pressure value;
Fig. 3 is the main composition sketch map of switch valve group, P
nRepresent to be sent in the positive pressure passageway branch road of positive negative pressure switch valve group, V
nBe sent to the branch road of positive negative pressure switch valve group in the expression negative pressure channel;
Fig. 4 is the structural representation of the embodiment of the invention, L1, and L2 ... Ln representes to lead to every branch road of chamber;
The specific embodiment
A kind of control pressurer system that is used for CMP rubbing head multi-cavity chamber provided by the invention belongs to technical field of manufacturing semiconductors, it is characterized in that comprising pressure source, control valve group, pressure sensor, CPU, digital-to-analogue and analog to digital conversion circuit etc.This control system realizes the pressure control to each chamber of far-end through pressure and the flow-control to each branch road.Every route malleation of control valve group is formed with two passages of negative pressure and a dual flow filter.Positive pressure passageway is by the pressure-reducing valve, malleation air bag, the electronically controlled proportional valve that link to each other successively with pressure source, just negative pressure switch valve group constitutes, wherein shared same pressure-reducing valve of each positive pressure passageway and malleation air bag.Negative pressure channel is made up of the vacuum switch valve that links to each other successively with pressure source, vacuum generator, vacuum air bag, vacuum regulating valve and positive negative pressure switch valve group, wherein the shared same vacuum switch valve of each negative pressure channel, vacuum generator and vacuum air bag.Positive negative pressure switch valve group output connects filter.Each chamber pressure that pressure sensor will collect is delivered to CPU through the A/D change-over circuit.
Further, described each bar branch line comprises malleation and two passages of negative pressure.
Further, the malleation air bag is added in the proportioning valve porch in described each positive pressure passageway.
Further, the vacuum regulating valve front end adds negative pressure gasbag in described each negative pressure channel.
Further, described sensor is the positive/negative pressure sensor.
Further, described A/D change-over circuit adopts 12 precision at least.
Further, described multi-region control pressurer system only is made up of a pressure source.
Further, described rubbing head multi-region is collapsible and expansion, can push mutually between the zone.
Below will combine accompanying drawing that pneumatic control system of the present invention is done further sets forth in detail.
Fig. 1 is multi-cavity chamber pressure control system global structure sketch map of the present invention.Control pressurer system of the present invention comprises pressure source 10, pressure sensor 30, and CPU40, A/D and D/A output unit 50, control valve group 60 is formed.Control valve group 60 is connecting each chamber 20 in pressure source and the rubbing head, and (Z1～Zn), chamber pressure is gathered to CPU40 through pressure sensor 30, is exported by output unit 50 control valve groups through after the software processes.Here, the rubbing head chamber is a flexibility or rigidity, coupling or non-coupling between the chamber.
In Fig. 2 system control valve group 60, each branch road Li is connecting pressure source 10, and (i=1～n), each branch road mainly is made up of positive pressure passageway and negative pressure channel with each chamber 20Zi of far-end.Positive pressure passageway is composed in series by pressure-reducing valve 68, malleation air bag 69, electronically controlled proportional valve 62 and positive negative pressure switch valve group 63 successively.Negative pressure channel mainly is composed in series by vacuum switch valve 65, vacuum generator 66 (the for example ZH series of SMC company production), vacuum air bag 61, vacuum regulating valve 64 and positive negative pressure switch valve group 63 successively.The output of positive negative pressure channel is connected to each chamber of far-end through dual flow filter 68, and positive negative pressure switch valve group 63 is the negative-pressure adsorption state when cutting off the power supply, and helps protecting silicon chip.When positive pressure passageway is worked; Control positive negative pressure switch valve group 63 tangential malleation paths by CPU40 through DO output unit 50; Close vacuum switch valve 65 simultaneously; Pressure according to the user sets is regulated electronically controlled proportional valve 62, and pressure sensor 30 is gathered chamber pressure to CPU40 in real time, realizes that by software control chamber pressure is consistent with setting pressure.During negative pressure channel work, positive negative pressure switch valve group 63 tangential negative pressure channels; Vacuum switch valve 65 is opened, and the positive pressure source 10 of its connection will trigger vacuum generator work, and the vacuum of chamber is regulated by vacuum regulating valve 64 and realized.
In addition, the present invention can also be communicated with atmosphere except can producing pressure and negative pressure.When being communicated with atmosphere, vacuum switch valve 65 cuts out, and this moment, vacuum generator did not produce vacuum, but was communicated with atmosphere, can realize that through positive negative pressure switch valve group 63 tangential vacuum loops each chamber links to each other with atmosphere.
Fig. 3 is the main composition sketch map of switch valve group.The detailed formation of switch valve group can be composed in parallel by two two-way valves (to be schemed a), also can be composed in series (figure b) by a two-bit triplet and two-way valve, perhaps be made up of a 3-position-3-way valve (figure c) etc.
Fig. 4 is embodiments of the invention, and control pressurer system of the present invention is connected to the swivel joint 80 of CMP equipment 90, and 120 chamber Z1～Zn link to each other with rubbing head, and sensor is installed on far-end swivel joint porch.When CMP equipment was carried out polished silicon slice, each district set control electronically controlled proportional valve 62 by the user and applies back pressure, simultaneously with sensor acquisition to real time data compare, make chamber pressure reach desired value fast by software control.Polishing finishes when grasping silicon chip and mobile silicon chip, and vacuum loop is opened, the malleation pathway closure.
Claims (5)
1. control pressurer system that is used for CMP rubbing head multi-cavity chamber is characterized in that containing: as source of the gas, control valve group, pressure sensor, A/D change-over circuit, D/A change-over circuit and the CPU of pressure source, wherein:
Total N of pressure sensor; N >=1; Gather N same in a far-end rubbing head chamber pressure respectively; Be input to each chamber pressure that collects among the CPU through an A/D change-over circuit with same N passage, the swivel joint of said N chamber on a wherein said N pressure sensor and the chemically mechanical polishing CMP equipment links to each other
The control valve group; Total N bar branch road; Each branch road correspondence is connecting a described chamber, and the input of said every branch road links to each other with pressure source, and the output of every branch road links to each other with input corresponding to the said chamber of this branch road; Every route malleation passage, negative pressure channel and a dual flow filter are formed, wherein:
Positive pressure passageway; Pressure-reducing valve, malleation air bag, electronically controlled proportional valve and positive negative pressure switch valve group by series connection successively constitute; The input of said pressure-reducing valve links to each other with the output of said pressure source, wherein shared same pressure-reducing valve of the positive pressure passageway of all branch roads and same malleation air bag
Negative pressure channel; Constitute by the vacuum switch valve, vacuum generator, negative pressure gasbag, vacuum regulating valve of the normally open of series connection successively and with the shared positive negative pressure switch valve group of said positive pressure passageway; The input of said vacuum switch valve links to each other with the output of described pressure source; The wherein shared same vacuum switch valve of the negative pressure channel of all branch roads, vacuum generator and same negative pressure gasbag
The output of described positive negative pressure switch valve group links to each other with the input of a dual flow filter, and the output of this dual flow filter links to each other with said chamber on the corresponding branch road,
Described positive negative pressure switch valve group is by a 3-position-3-way valve, or two two-way valves parallel with one another, or a two-position three-way valve and a two-way valve composition of series connection each other,
CPU; For each said chamber is set a chamber pressure value; Simultaneously; Set the electronically controlled proportional valve of a differential pressure signal output in said positive pressure passageway and export said setting chamber pressure and the difference of surveying chamber pressure, difference is greater than zero, and expression continues pressurization to said chamber; Difference is less than zero; Expression also is provided with said chamber depressurization: the switch-over control signal output while links to each other with the pulldown start-up control signal input part of the vacuum switch valve of said negative pressure channel and with the control signal input that switches by required running status of described positive negative pressure switch valve group, between startup pulldown process and chamber pressure regulation process, switches; The differential pressure signal of said differential pressure signal output output outputs to the control signal input of electronically controlled proportional valve in the said positive pressure passageway after through the D/A change-over circuit, and the air pressure after the regulation and control is sent to the chamber of correspondence after said switch-over control signal control is down via said positive negative pressure switch valve group, dual flow filter; Said pulldown start-up control signal is opened the vacuum switch valve output of said negative pressure channel, through the vacuum regulating valve pressure regulation after said dual flow filter is sent to corresponding chamber, under off-position, described positive negative pressure switch valve group tangential negative pressure channel.
2. a kind of control pressurer system that is used for CMP rubbing head multi-cavity chamber as claimed in claim 1 is characterized in that: described vacuum regulating valve is any in manual pressure regulating valve, automatically controlled pressure regulator valve and the electronically controlled proportional valve.
3. a kind of control pressurer system that is used for CMP rubbing head multi-cavity chamber as claimed in claim 1 is characterized in that: when the vacuum switch valve was opened, described vacuum generator produced vacuum; When the vacuum switch valve cut out, described vacuum generator linked to each other with atmosphere.
4. a kind of control pressurer system that is used for CMP rubbing head multi-cavity chamber as claimed in claim 1, it is characterized in that: described pressure sensor is installed on the air inlet end of said CMP equipment rubbing head.
5. a kind of control pressurer system that is used for CMP rubbing head multi-cavity chamber as claimed in claim 1, it is characterized in that: described pressure sensor is positive B/P EGR Back Pressure Transducer EGR.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201110002122A CN102133731B (en) | 2011-01-06 | 2011-01-06 | Pressure control system for plurality of chambers of CMP (chemical mechanical polishing) head |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201110002122A CN102133731B (en) | 2011-01-06 | 2011-01-06 | Pressure control system for plurality of chambers of CMP (chemical mechanical polishing) head |
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| CN102133731A CN102133731A (en) | 2011-07-27 |
| CN102133731B true CN102133731B (en) | 2012-10-10 |
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| CN201110002122A Expired - Fee Related CN102133731B (en) | 2011-01-06 | 2011-01-06 | Pressure control system for plurality of chambers of CMP (chemical mechanical polishing) head |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| TWI595339B (en) * | 2014-10-08 | 2017-08-11 | 慧盛材料美國責任有限公司 | Low pressure fluctuation flow control apparatus and method |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| JP5956287B2 (en) * | 2012-08-23 | 2016-07-27 | 株式会社ディスコ | Grinding equipment |
| CN105773397B (en) * | 2016-03-09 | 2017-09-29 | 天津华海清科机电科技有限公司 | Chemically-mechanicapolish polish multi-region pressure On-line Control algorithm |
| CN105701320A (en) * | 2016-03-09 | 2016-06-22 | 天津华海清科机电科技有限公司 | Static pressurization control algorithm of multi-pressure-partition polishing head |
| CN108032211B (en) * | 2017-12-11 | 2020-04-28 | 北京半导体专用设备研究所（中国电子科技集团公司第四十五研究所） | Air pressure detection device and polishing equipment |
| CN108172534B (en) * | 2017-12-26 | 2020-02-11 | 北京半导体专用设备研究所（中国电子科技集团公司第四十五研究所） | Air pressure monitoring method and device and electronic equipment |
| CN110032223A (en) * | 2019-04-18 | 2019-07-19 | 安徽皖仪科技股份有限公司 | High-precision positive/negative-pressure is double to apply automatically controlled regulator |
| CN113400195B (en) * | 2021-07-21 | 2022-08-19 | 北京烁科精微电子装备有限公司 | Method and system for online partition adjustment of loading and unloading pressure of polishing head |
| CN115256218A (en) * | 2022-06-20 | 2022-11-01 | 北京烁科精微电子装备有限公司 | Pneumatic control device for polishing head and polishing equipment thereof |
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| US5443416A (en) * | 1993-09-09 | 1995-08-22 | Cybeq Systems Incorporated | Rotary union for coupling fluids in a wafer polishing apparatus |
| US6203408B1 (en) * | 1999-08-26 | 2001-03-20 | Chartered Semiconductor Manufacturing Ltd. | Variable pressure plate CMP carrier |
| CN201579701U (en) * | 2009-11-26 | 2010-09-15 | 中国电子科技集团公司第四十五研究所 | Lower pressure control system of CMP polishing pad finisher |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2003133272A (en) * | 2001-10-24 | 2003-05-09 | Nec Kansai Ltd | Cmp apparatus |
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5443416A (en) * | 1993-09-09 | 1995-08-22 | Cybeq Systems Incorporated | Rotary union for coupling fluids in a wafer polishing apparatus |
| US6203408B1 (en) * | 1999-08-26 | 2001-03-20 | Chartered Semiconductor Manufacturing Ltd. | Variable pressure plate CMP carrier |
| CN201579701U (en) * | 2009-11-26 | 2010-09-15 | 中国电子科技集团公司第四十五研究所 | Lower pressure control system of CMP polishing pad finisher |
Non-Patent Citations (1)
| Title |
|---|
| JP特开2003-133272A 2003.05.09 |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| TWI595339B (en) * | 2014-10-08 | 2017-08-11 | 慧盛材料美國責任有限公司 | Low pressure fluctuation flow control apparatus and method |
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