CN104682917B - Impedance matching network for plasma reactor - Google Patents
Impedance matching network for plasma reactor Download PDFInfo
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- CN104682917B CN104682917B CN201310613328.6A CN201310613328A CN104682917B CN 104682917 B CN104682917 B CN 104682917B CN 201310613328 A CN201310613328 A CN 201310613328A CN 104682917 B CN104682917 B CN 104682917B
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- capacitance
- impedance matching
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- matching network
- variable vacuum
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Abstract
The present invention provides a kind of impedance matching network for plasma reactor, including an at least inductance and a variable-capacitance unit, the variable-capacitance unit includes at least one variable vacuum capacitance, the variable vacuum capacitance includes two parallel battery lead plates, one ring-shaped piezo ceramic plate is set between two battery lead plate, the ring-shaped piezo ceramic plate connects a driving power supply, and the hollow region of the ring-shaped piezo ceramic plate sets an arc-shaped electrode plate.Variable vacuum capacitance in impedance matching network of the present invention utilizes the inverse piezoelectric effect of piezoceramic material, when applying alternating driving voltages to piezoelectric ceramics, piezoelectric ceramic energy is rapid to occur stretching motion along voltage-drop loading direction, the distance of relatively another pole plate of arc-shaped electrode plate is set to change, and then change the capacitance of variable vacuum capacitance rapidly, realize vacuum variable capacitor can in musec order big minor adjustment, meet the need for the output of plasma impedance rapid radio frequency power source changes.
Description
Technical field
The present invention relates to the impedance match technique neck in the manufacture field of semiconductor devices, more particularly to plasma reactor
Domain.
Background technology
Plasma processing apparatus is widely used in manufacture integrated circuit（IC）Or in the manufacturing process of MEMS.Its
In a significant purposes be exactly plasma reactor for being performed etching to semiconductor chip.Containing big in plasma
Electronics, ion, the atom of excitation state, molecule and the free radical isoreactivity particle of amount, these active particles are in semiconductor chip table
Various physical and chemical reactions occur for face, so that surface of semiconductor chip performance is changed.Typically, for plasma
For processing module, as the mode of generation plasma, it can be generally divided into and utilize corona（glow）Electric discharge or high frequency are put
Electricity, and utilize the modes such as microwave.
In the plasma treatment module of high-frequency discharge mode, in order to which the radio-frequency power supply power for exciting plasma is had
Being carried on discharge system for effect needs to access impedance matching network between radio-frequency power supply and discharge system, and impedance matching network leads to
Often include electric capacity and inductance, when the impedance of impedance matching network needs change, generally realized by changing capacitance size to resistance
The adjustment of anti-matching network.Due to technological parameter in actual applications（Such as radio-frequency power, air pressure, process materials or gas）Change
Change can cause the rapid change of plasma impedance, be the application that impulse modulation is exported, pulse especially for radio frequency power source
Radio frequency power output control reactive plasma etching technics has been widely used, and its general principle is radio frequency power source output by arteries and veins
The radio-frequency power of modulated is used to produce plasma, and the density of produced plasma changes with pulse generation, therein
Charged particle（Electronics and ion）Quantity intermittence change, so that the corrasion of plasma is controlled and buffered.
In this application, in plasma applications radio frequency power source can change within the musec order time high frequency that is carried on discharge system with
Low frequency power, causes rapid change of the impedance of plasma in gsec, this requires impedance matching network to provide phase
With the impedance matching in the order of magnitude time to maintain the continuous-stable of plasma to discharge.Variable capacitance in traditional matching network
It is by motor-driven, it is impossible to meet quick regulation of the variable capacitance in musec order, cause impedance matching network can not
Itself size is adjusted in time, so that in time can not effectively be carried in radio-frequency power supply power on discharge system, and then can not be produced
Plasma distribution needed for raw technique.
The content of the invention
In order to solve the above-mentioned technical problem, the present invention provides a kind of impedance matching network for plasma reactor,
Including an at least inductance and a variable-capacitance unit, the variable-capacitance unit includes at least one variable vacuum capacitance, described
Variable vacuum capacitance includes setting a ring-shaped piezo ceramic plate, the ring-shaped piezo ceramic between two battery lead plates, two battery lead plate
Plate connects a driving power supply, and the hollow region of the ring-shaped piezo ceramic plate sets an arc-shaped electrode plate.
It is preferred that, the variable vacuum capacitance unit includes several variable vacuum capacitances, several described variable vacuum
Electric capacity is in parallel or series.
It is preferred that, a high-power MOS TFET FETs are connected between the variable-capacitance unit and the driving power supply
Unit, the high-power MOS TFET FETs unit includes several high-power MOSs TFET FETs.
It is preferred that, the quantity of the high-power MOS TFET FETs is equal with the quantity of the variable vacuum capacitance, often
Individual high-power MOS TFET FETs connect a variable vacuum capacitance.
It is preferred that, the high-power MOS TFET FETs unit connects a micro-control unit MCU.
It is preferred that, the capacitance size of the variable vacuum capacitance is adjusted in musec order.
It is preferred that, several described variable vacuum capacitances are according to impedance matching demand in parallel or series into a circuit, institute
State circuit and connect a driving power supply.
It is preferred that, the impedance matching network connection RF source power source or RF bias power source.
It is preferred that, the RF source power source and the RF bias power source are output as impulse modulation output.
It is preferred that, the ring-shaped piezo ceramic plate is connected by a Piezoelectric Ceramic electrode and the driving power supply.
The advantage of the invention is that：Variable vacuum capacitance in impedance matching network of the present invention uses piezoelectric ceramics
Material makes, and utilizes the inverse piezoelectric effect of piezoceramic material, when applying alternating driving voltages to piezoelectric ceramics, piezoelectric ceramics
Rapid can occur stretching motion along voltage-drop loading direction, and then change the capacitance of variable vacuum capacitance rapidly, generally micro-
It can change in second-time.By using multiple variable vacuum capacitances mode in parallel, high-power MOS TFET FETs are utilized
Unit and MCU controls can realize the combination of any number of variable vacuum capacitance, and then realize being adjusted flexibly for matching impedance.
Technical solutions according to the invention have overturned the conventional regulative mode using motor-driven conventional variable vacuum capacitance, utilize pressure
The inverse piezoelectric effect of electroceramics material makes vacuum variable capacitor, realizes that vacuum variable capacitor can realize size in musec order
Regulation, the need for meeting the rapid radio frequency power source output change of plasma impedance.
Brief description of the drawings
By reading the detailed description made with reference to the following drawings to non-limiting example, further feature of the invention,
Objects and advantages will become more apparent upon：
Fig. 1 shows impedance matching network of the present invention and plasma reactor attachment structure schematic diagram；
Fig. 2 shows variable vacuum capacitance structural representation of the present invention；
Fig. 3 shows ring-shaped piezo ceramic plate of the present invention and its arc-shaped electrode plate attachment structure schematic diagram；
Fig. 4 shows the structural representation of impedance matching network of the present invention；
Fig. 5 shows the structural representation that high-power MOS TFET FETs are connected with variable vacuum capacitance.
Embodiment
To make the purpose, technical scheme and advantage of the embodiment of the present invention clearer, below in conjunction with the embodiment of the present invention
In accompanying drawing, the technical scheme in the embodiment of the present invention is clearly and completely described, it is clear that described embodiment is
A part of embodiment of the present invention, rather than whole embodiments.Based on the embodiment in the present invention, those of ordinary skill in the art
The every other embodiment obtained under the premise of creative work is not made, belongs to the scope of protection of the invention.
In Plasma Industry application, in order to which the radio-frequency power supply power for exciting plasma is effectively carried in into electric discharge
Need to access impedance matching network between power supply and discharge system in system.Fig. 1 show impedance matching network of the present invention with
Plasma reactor attachment structure schematic diagram.As shown in figure 1, plasma reactor includes vacuum reaction chamber 100, it is described true
Bottom electrode 110 including Top electrode 105 and the lower section of Top electrode 105 in empty reaction chamber, pending semiconductor chip is located at lower electricity
The top of pole 110.When the radio-frequency power of radio frequency power source is applied on bottom electrode 110, between Top electrode 105 and bottom electrode 110
Plasma 120 can be formed, 120 pairs of the plasma surface of semiconductor chip carries out physical bombardment and chemical reaction, completed
Etching process.The radio frequency power source of plasma reactor generally includes at least one RF bias power source and a radio frequency source
In power source, the present embodiment, a RF bias power source 170 and a RF source power source 160 are applied to lower electricity simultaneously
On pole 110.RF bias power source 170 and RF source power source 160 pass through impedance matching network 140 and impedance matching net respectively
Radio-frequency power is effectively applied on bottom electrode 110 by network 150.
Those skilled in the art are apparent from, in plasma reactor, and the setting of impedance matching network must assure that radio frequency
The matches impedances of plasma 120 produced in the impedance of power source and vacuum reaction chamber 100 are due to technique in actual applications
The change of parameter such as radio-frequency power, air pressure, process materials or gas can cause the rapid change of plasma impedance, particularly work as
When radio-frequency power is output as impulse modulation output, to ensure the impedance variations of plasma 120 and radio frequency in vacuum reaction chamber 100
The pulse exporting change of power source is consistent, and the impedance matching network between radio frequency power source and plasma needs to carry out and radio frequency
The equal change of the pulse output frequencies of power source.Generally, impedance matching network at least includes an inductance and a variable capacitance,
In the prior art, the impedance adjustment to impedance matching network mainly passes through the inductance of blocked impedance matching network, change impedance
The variable capacitance of matching network is realized.In plasma reactor, variable capacitance is usually variable vacuum capacitance.Traditional
Variable vacuum capacitance is by motor-driven, it is impossible to realize the quick change of capacitance, is pulse particularly in radio frequency power source
In the application of output, when being exported due to radio frequency power source for pulse, radio frequency power source can change loading within the musec order time
High and low frequency power on plasma, causes rapid change of the plasma impedance within the musec order time, this is just
It is required that the impedance matching one that impedance matching network can be provided in the same order time maintains the continuous-stable of plasma to put
Electricity.Traditional can not meet this requirement by motor-driven variable vacuum capacitance.
Fig. 2 shows variable vacuum capacitance structural representation of the present invention, and the variable vacuum capacitance 1510 includes two
One is set to be made pottery with the almost parallel ring piezoelectric of two battery lead plate between parallel battery lead plate 1511 and 1512, two battery lead plate
Porcelain plate 1513.Ring-shaped piezo ceramic plate 1513 connects a driving power supply 153, annular pressure by a Piezoelectric Ceramic electrode 1515
The hollow region of electroceramics plate 1513 sets an arc-shaped electrode plate 1514, and battery lead plate 1512 constitutes parallel with arc-shaped electrode plate 1514
Plate vacuum capacitance, Fig. 3 shows the ring-shaped piezo ceramic plate and its arc-shaped electrode plate attachment structure schematic diagram.Piezoelectric ceramics is one
Planting can be by mechanical energy and the ceramic material of the mutual phase transformation of electric energy, in the present invention, on ring-shaped piezo ceramic plate 1513
An alternation driving power supply 153 is connected, using the inverse piezoelectric effect of piezoceramic material, makes piezoceramic material in alternating electric field
Driving is lower to produce mechanical movement, i.e., when applying alternating electric field to ring-shaped piezo ceramic plate 1513, ring-shaped piezo ceramic plate 1513
Shape can carry out stretching motion along voltage-drop loading direction, its stretching motion force the arc-shaped electrode plate 1514 of its hollow region to be sent out
Raw compression or extensional motion, cause the distance between arc-shaped electrode plate 1514 and battery lead plate 1512 d to change, it is known that variable true
The capacitance calculation formula of empty electric capacity is（ε in formula0For permittivity of vacuum, S is polar plate area, and d is between pole plate
Away from）, so as to realize the quick change to electric capacity., can be by selecting different arcs using technical solutions according to the invention
The curvature of battery lead plate, Quality Design and making material etc. realize the different rate of change of capacitance of variable vacuum torch and capacitance regulation
Response time.In the present embodiment, the driving power supply 153 for acting on ring-shaped piezo ceramic plate 1513 is AC power.
Fig. 4 shows the structural representation of impedance matching network of the present invention, the present embodiment selection and RF source power source
160 impedance matching networks 150 matched are described in detail, the impedance matching net being connected with RF bias power source 170
Network 140 can use the technical scheme same with impedance matching network 150, will not be repeated here.In the schematic diagram shown in Fig. 4
In, the connection of RF source power source 160 impedance matching network 150, it is variable true that impedance matching network 150 includes an inductance 152 and one
Empty capacitor cell 151, connects a high-power MOS TFET FETs between variable vacuum capacitance unit 151 and driving power supply 153
Unit 155 a, Micro-processor MCV 154 connects described high-power MOS TFET FETs unit 155.What the present embodiment was used
Variable vacuum capacitance unit 151 includes multiple variable vacuum capacitances 1510, because the ring piezoelectric of variable vacuum capacitance 1510 is made pottery
Porcelain plate 1513 stretches limited extent, and it drives the stretching of arc-shaped electrode plate 1514 and suppressed range smaller, arc-shaped electrode plate 1514
Distance between the battery lead plate parallel with two changes smaller, ultimately results in variable capacitance capacitance and changes smaller, it is impossible to meets impedance
The adjustment demand of distribution network.The present invention is using multiple variable vacuum capacitances 1510 in parallel or series into a variable vacuum capacitance list
Member 151, by set variable vacuum capacitance 1510 quantity and each variable vacuum capacitance change size come to variable vacuum
The equivalent capacity capacitance of capacitor cell 151 is adjusted.Because several variable vacuum capacitances 1510 are in parallel or series into one
Circuit, therefore same driving power supply 153 can be applied to the circuit.Fig. 5 shows high-power MOS TFET FETs and variable true
The structural representation of empty capacitance connection；In the embodiment described in Fig. 5, high-power MOS TFET FETs unit 155 include with
The high-power MOS TFET FETs 1551 of the variable correspondence of vacuum capacitance 1510 number, each high-power MOS TFET FETs
1551 one variable vacuum capacitance 1510 of connection.High-power MOS TFET FETs control the load driver voltage of driving power supply 153
Onto the ring-shaped piezo ceramic plate of variable vacuum capacitance 1510, realized and driven by the break-make of high-power MOS TFET FETs
Whether voltage drives variable vacuum capacitance 1510, and then determines that the variable difference of vacuum capacitance unit 151 for participating in impedance matching can
Become the combination of vacuum capacitance quantity.In addition, high-power MOS TFET FETs unit 155 is also connected with a Micro-processor MCV 154,
MCU154 can by controlling the break-make of each high-power MOS TFET FETs to select variable vacuum capacitance 1510,
When a certain high-power MOS TFET FETs 1551 are conducting state, the variable vacuum capacitance being attached thereto can be due to inside
Piezoelectric ceramics is moved under driving voltage effect, and then changes capacitance, when a certain high-power MOS TFET FETs 1551 are
During cut-off state, the variable capacitance size being attached thereto keeps constant and controls TFET effects of high-power MOS by using MCU154
The break-make of pipe unit is answered, and then controls variable vacuum unit 151 to realize the combination of any variable vacuum capacitance quantity, and then
Realize that the impedance to impedance matching network 150 is adjusted flexibly, it is ensured that the firm power input of discharge system.
Variable vacuum capacitance in impedance matching network of the present invention is made using piezoceramic material, utilizes piezoelectricity
The inverse piezoelectric effect of ceramic material, when applying alternating driving voltages to piezoelectric ceramics, piezoelectric ceramic energy adds rapidly along voltage
Carry direction and occur stretching motion, and then change the capacitance of variable vacuum capacitance rapidly, can change generally in musec order.
, can be with using high-power MOS TFET FETs unit and MCU controls by using multiple variable vacuum capacitances mode in parallel
The combination of any number of variable vacuum capacitance is realized, and then realizes being adjusted flexibly for matching impedance.Technology of the present invention
Scheme has overturned the conventional shaping modes using motor-driven conventional variable vacuum capacitance, utilizes the inverse pressure of piezoceramic material
Electrical effect makes vacuum variable capacitor, realizes that vacuum variable capacitor can realize big minor adjustment in musec order, meets plasma
The need for the rapid radio frequency power source output of body impedance changes.
Although the present invention is disclosed as above with preferred embodiment, it is not for limiting the present invention, any this area skill
Art personnel without departing from the spirit and scope of the present invention, can make possible variation and modification, therefore the guarantor of the present invention
The scope that shield scope should be defined by the claims in the present invention is defined.
Claims (9)
1. a kind of impedance matching network for plasma reactor, including an at least inductance and a variable-capacitance unit, its
It is characterised by：The variable-capacitance unit includes at least one variable vacuum capacitance, and the variable vacuum capacitance includes two electrodes
One ring-shaped piezo ceramic plate is set between plate, two battery lead plate, and the ring-shaped piezo ceramic plate connects a driving power supply, the ring
The hollow region of shape piezoelectric ceramic plate sets an arc-shaped electrode plate, and the ring-shaped piezo ceramic plate passes through Piezoelectric Ceramic electricity
Pole and driving power supply connection.
2. impedance matching network according to claim 1, it is characterised in that：The variable vacuum capacitance unit includes some
Individual variable vacuum capacitance, several described variable vacuum capacitances are in parallel or series.
3. impedance matching network according to claim 2, it is characterised in that：The variable-capacitance unit and driving electricity
A high-power MOS TFET FET units are connected between source, the high-power MOS TFET FETs unit includes several
High-power MOS TFET FETs.
4. impedance matching network according to claim 3, it is characterised in that：The high-power MOS TFET FETs
Quantity is equal with the quantity of the variable vacuum capacitance, and each high-power MOS TFET FETs connect a variable vacuum electric
Hold.
5. impedance matching network according to claim 3, it is characterised in that：The high-power MOS TFET FET lists
One micro-control unit MCU of member connection.
6. impedance matching network according to claim 1, it is characterised in that：The capacitance size of the variable vacuum capacitance exists
Adjusted in musec order.
7. impedance matching network according to claim 2, it is characterised in that：Several described variable vacuum capacitances are according to resistance
Anti- matching demand is in parallel or series into a circuit, and the circuit connects a driving power supply.
8. impedance matching network according to claim 1, it is characterised in that：The impedance matching network connects radio frequency source work(
Rate source or RF bias power source.
9. impedance matching network according to claim 8, it is characterised in that：The RF source power source and the radio frequency are inclined
Put power source and be output as impulse modulation output.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310613328.6A CN104682917B (en) | 2013-11-27 | 2013-11-27 | Impedance matching network for plasma reactor |
| TW103140138A TWI571053B (en) | 2013-11-27 | 2014-11-19 | Impedance Matching Network for Plasma Reactors |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310613328.6A CN104682917B (en) | 2013-11-27 | 2013-11-27 | Impedance matching network for plasma reactor |
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| Publication Number | Publication Date |
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| CN104682917A CN104682917A (en) | 2015-06-03 |
| CN104682917B true CN104682917B (en) | 2017-09-26 |
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| CN201310613328.6A Active CN104682917B (en) | 2013-11-27 | 2013-11-27 | Impedance matching network for plasma reactor |
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| US10899605B2 (en) * | 2018-03-05 | 2021-01-26 | Sharp Kabushiki Kaisha | MEMS device and manipulation method for micro-objects |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101989525A (en) * | 2009-08-05 | 2011-03-23 | 中微半导体设备(上海)有限公司 | Plasma processing cavity and switchable matching network with switchable offset frequency |
| CN102054587A (en) * | 2009-10-27 | 2011-05-11 | 富士通株式会社 | Variable capacitive element, variable capacitive device, and method for driving the variable capacitive element |
| CN103311082A (en) * | 2012-03-13 | 2013-09-18 | 中微半导体设备(上海)有限公司 | Radio frequency matching network and plasma processing chamber applying same |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7936553B2 (en) * | 2007-03-22 | 2011-05-03 | Paratek Microwave, Inc. | Capacitors adapted for acoustic resonance cancellation |
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- 2013-11-27 CN CN201310613328.6A patent/CN104682917B/en active Active
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- 2014-11-19 TW TW103140138A patent/TWI571053B/en active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101989525A (en) * | 2009-08-05 | 2011-03-23 | 中微半导体设备(上海)有限公司 | Plasma processing cavity and switchable matching network with switchable offset frequency |
| CN102054587A (en) * | 2009-10-27 | 2011-05-11 | 富士通株式会社 | Variable capacitive element, variable capacitive device, and method for driving the variable capacitive element |
| CN103311082A (en) * | 2012-03-13 | 2013-09-18 | 中微半导体设备(上海)有限公司 | Radio frequency matching network and plasma processing chamber applying same |
Also Published As
| Publication number | Publication date |
|---|---|
| CN104682917A (en) | 2015-06-03 |
| TWI571053B (en) | 2017-02-11 |
| TW201526536A (en) | 2015-07-01 |
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Address after: 201201 No. 188 Taihua Road, Jinqiao Export Processing Zone, Pudong New Area, Shanghai Patentee after: Medium and Micro Semiconductor Equipment (Shanghai) Co., Ltd. Address before: 201201 No. 188 Taihua Road, Jinqiao Export Processing Zone, Pudong New Area, Shanghai Patentee before: Advanced Micro-Fabrication Equipment (Shanghai) Inc. |