CN114337302A - High-power sputtering power supply - Google Patents
High-power sputtering power supply Download PDFInfo
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- CN114337302A CN114337302A CN202111666013.9A CN202111666013A CN114337302A CN 114337302 A CN114337302 A CN 114337302A CN 202111666013 A CN202111666013 A CN 202111666013A CN 114337302 A CN114337302 A CN 114337302A
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- 238000004544 sputter deposition Methods 0.000 title claims abstract description 41
- 238000001914 filtration Methods 0.000 claims abstract description 23
- 230000001276 controlling effect Effects 0.000 claims abstract description 4
- 230000001105 regulatory effect Effects 0.000 claims abstract description 4
- 238000005070 sampling Methods 0.000 claims description 22
- 238000002955 isolation Methods 0.000 claims description 7
- 238000004590 computer program Methods 0.000 claims description 3
- 238000000034 method Methods 0.000 abstract description 7
- 239000004065 semiconductor Substances 0.000 abstract description 3
- 238000004146 energy storage Methods 0.000 description 6
- 238000001514 detection method Methods 0.000 description 5
- 239000010408 film Substances 0.000 description 5
- 238000000576 coating method Methods 0.000 description 4
- 239000011248 coating agent Substances 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 238000011160 research Methods 0.000 description 3
- 230000033228 biological regulation Effects 0.000 description 2
- 230000009977 dual effect Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000010891 electric arc Methods 0.000 description 2
- 238000000168 high power impulse magnetron sputter deposition Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 238000005240 physical vapour deposition Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000003990 capacitor Substances 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 238000000151 deposition Methods 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 238000001755 magnetron sputter deposition Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 238000012827 research and development Methods 0.000 description 1
- 239000010409 thin film Substances 0.000 description 1
- 238000004832 voltammetry Methods 0.000 description 1
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Abstract
The invention relates to a high-power sputtering power supply, which comprises a rectifying circuit, an inverter circuit, a transformer, a filter circuit, a controller and a storage medium which are electrically connected in sequence, wherein the storage medium stores a program, and the program realizes the following steps when being executed by the controller: detecting the output voltage and the output current of the output rectifying and filtering circuit in real time; taking the product of the output voltage and the output current as output power, and obtaining a voltage effective value by a PI regulator according to the difference value of the output power and the target power value; and regulating the difference value of the voltage effective value and the output voltage by a PI regulator to obtain a PWM (pulse-width modulation) modulation wave for controlling the on-off of each switching tube in the controllable H-bridge inverter circuit. The invention can realize the reliable use of the high-power sputtering power supply on semiconductor key process equipment.
Description
Technical Field
The invention relates to the field of power electronics, in particular to a high-power sputtering power supply.
Background
The magnetron sputtering (HPPMS) technology is one of the main thin film preparation technologies of Physical Vapor Deposition (PVD), and compared with other coating methods, the method has the advantages of low-temperature deposition, easy film thickness control, good repeatability, moderate particle energy of sputtering film formation, no generation of large particles and the like. In recent decades, more and more researchers have been devoted to research on discharge characteristics and plasma characteristics of HPPMS technology, and mainly research on a corresponding relationship between an expression form of a target current and a discharge plasma by researching a discharge voltammetry characteristic curve.
At present, a sputtering power supply is mainly used on semiconductor sputtering coating equipment and is a key part of the sputtering coating equipment. There are two major power brands used, PINNACELE (AE corporation) and Hottinge (Germany). PINNALE (AE corporation) accounts for more than 90%, and Hottinge (Germany) accounts for less than 10%. The two brands are imported brands, and the sputtering power supply brands are not put into use at home until now.
The sputtering power supply mainly solves the problems of the scheme of a high-power sputtering power supply and the research of a topological scheme, and the key of the research and development success and failure lies in how to quickly realize the switching from a higher ignition voltage to a lower output voltage range after the ignition voltage is output instantly, and if the switching is too slow, arcing can occur to cause the damage of materials and equipment.
Disclosure of Invention
The invention aims to realize the reliable use of a high-power sputtering power supply on semiconductor key process equipment.
Therefore, the high-power sputtering power supply comprises a rectifying circuit, a controllable H-bridge inverter circuit, an isolation step-up transformer, an output rectifying and filtering circuit and a controller which are electrically connected in sequence, wherein the controller controls the on-off of each switching tube in the controllable H-bridge inverter circuit through a PWM (pulse-width modulation) wave;
further comprising a computer storage medium storing a computer program that when executed by the controller performs the steps of:
detecting the output voltage and the output current of the output rectifying and filtering circuit in real time;
taking the product of the output voltage and the output current as output power, and obtaining a voltage effective value by a PI regulator according to the difference value of the output power and a target power value;
and regulating the difference value of the voltage effective value and the output voltage by a PI regulator to obtain the PWM modulation wave for controlling the on-off of each switching tube in the controllable H-bridge inverter circuit.
Further, the controllable H-bridge inverter circuit adopts an LLC mode. The positive output end of the output rectifying and filtering circuit is connected to the negative output end of the output rectifying and filtering circuit through an electric control switch series resistor R6, and the electric control switch is connected with the controller; and the controller drives the electric control switch to be closed after the high-power sputtering power supply stops outputting. The controllable H-bridge inverter circuit works at least at a switching frequency more than hundreds of kHz, the electric control switch is a switching tube Q6, the collector of the switching tube Q6 is connected with the positive output end of the output rectifying and filtering circuit, the emitter of the switching tube Q6 is connected with the negative output end of the output rectifying and filtering circuit through a resistor R6, and the base of the switching tube Q6 is connected with the controller.
Further, the controller stops the output of the high-power sputtering power supply and drives the electronic control switch to be closed when detecting that the output current is increased sharply or detecting that the output voltage is decreased sharply. The sampling circuit of the output current and/or the output voltage is a pure mode circuit. The sampling circuit of the output current comprises a sampling resistor, a first differential operational amplifier and a first follower, wherein the sampling resistor is connected with the positive output end of the output rectifying and filtering circuit in series, two input ends of the first differential operational amplifier are respectively connected with two ends of the sampling resistor, and the output end of the first differential operational amplifier is connected to the controller through the first follower. The sampling circuit of the output voltage comprises a second differential operational amplifier and a second follower, two input ends of the second differential operational amplifier are respectively connected with two output ends of the output rectifying and filtering circuit, and the output end of the second differential operational amplifier is connected to the controller through the second follower.
Further, the rectification circuit is a 6-pulse PFC rectification circuit.
Further, the primary-secondary side ratio of the isolation boosting transformer is 1: 3.
The invention has the following beneficial technical effects:
in order to reliably solve the problem of fast switching, the power supply adopts a double-closed-loop PI control mode, a voltage inner loop and a power outer loop, the voltage inner loop compares an output direct-current voltage with a voltage effective value generated by the power outer loop to form a PWM value, wherein the output quantity of the outer loop is finally controlled by a setting value (a target power value) of a controller, so that the constant power characteristic is realized, the dynamic characteristic of the system can be improved by increasing the voltage inner loop under the condition of constant power, the response speed is improved, the power supply under the constant power mode can be quickly adjusted to a normal voltage range according to the load characteristic, in addition, the voltage inner loop also plays a role of voltage limitation, the voltage output cannot exceed the upper limit no matter how the power outer loop is adjusted, and even if the output power of the outer loop is insufficient, the voltage of the inner loop is only output according to the set upper limit voltage at most, and the purpose of limiting the voltage output of the power supply is achieved.
The power supply adopts the power outer ring and the voltage inner ring, thereby not only achieving the purpose of rapid power regulation, but also limiting the voltage output higher than the ignition voltage, and ensuring the sputtering equipment to be safe and reliable.
Drawings
FIG. 1 is a circuit topology of a high power sputtering power supply of the present invention.
FIG. 2 is a control flow of the dual closed loop PI control method of the high power sputtering power supply of the present invention.
Fig. 3 is a schematic diagram of a double closed loop PI of the high power sputtering power supply of the present invention.
Fig. 4 is a circuit topology of the sampling circuit of the present invention.
Detailed Description
The technical solution of the present invention is further explained with reference to the accompanying drawings and specific embodiments.
As shown in fig. 1, the sputtering power supply consists of five parts, namely a 6-pulse PFC rectifying circuit, a controllable H-bridge inverter circuit, an isolation step-up transformer, an output rectifying and filtering circuit, a quick discharge circuit and a controller.
The three-phase AC380V power supply is rectified by a 6-pulse PFC rectifying circuit to obtain DC513V (direct current bus voltage) direct current voltage, then is inverted into single-phase alternating current output through an H bridge, then is boosted through an isolation boosting transformer (the primary-secondary side ratio is 1:3), and is rectified again to obtain the voltage output with the highest DC 1500V. The rated voltage output of the power supply is DC400V, the rated current output is 50A, and considering that the ignition voltage is DC1500V, the range of the output voltage of the power supply is DC 400V-DC 1550V.
In the sputtering power supply of the embodiment, the 6-pulse PFC rectifying circuit can improve the power of the input side and reduce the influence on the harmonic wave of the power grid; the LLC inversion mode improves the switching frequency and reduces the switching loss; the discharge loop can indirectly reduce the storage energy value of the output filter element; the controller, i.e. the controller, can quickly bring the power supply back from the ignition voltage to the normal voltage range by means of a double closed loop control.
The solution of how to quickly switch to DC 400V-800V after 1500V of ignition voltage is output is implemented by providing a computer readable storage medium storing a specific program, wherein the computer readable storage medium stores a computer program, and the program when executed by the controller implements the following steps, as shown in fig. 2 and 3, including:
s1, detecting output voltage and output current of an output rectifying and filtering circuit in real time;
s2, taking the product of the output voltage and the output current as output power, and obtaining a voltage effective value by a PI regulator according to the difference value of the output power and a target power value;
and S3, regulating the difference value between the voltage effective value and the output voltage by a PI regulator to obtain the PWM modulation wave for controlling the on-off of each switching tube in the controllable H-bridge inverter circuit.
Specifically, the sputtering power supply of this embodiment operates in a constant power operation mode, after power setting, the controller tries to increase the output voltage, after reaching the ignition voltage (DC1500V), the current will rapidly increase due to the constant power, at this time, the output power is rapidly increased, the controller compares the output direct current voltage with the effective voltage value generated by the power outer loop through a dual closed loop PI control manner, the voltage inner loop + the power outer loop, the voltage inner loop forms a PWM value, and the power output is rapidly adjusted to make the output power conform to the set power.
Under the condition of constant power, the dynamic characteristic of a system can be improved by adding the voltage inner ring, the response speed is improved, the power supply in the constant power mode can be quickly adjusted to a normal voltage range according to the load characteristic, the voltage inner ring also plays a role in voltage limitation, the voltage output cannot exceed the upper limit no matter how the power outer ring is adjusted, even if the output power of the outer ring is insufficient, the voltage of the inner ring is only output according to the set upper limit voltage at most, and the purpose of limiting the voltage output of the power supply is achieved. The sputtering power supply of the embodiment adopts the power outer ring and the voltage inner ring, so that the purpose of quickly adjusting power is achieved, the voltage output higher than the ignition voltage is limited, the rigidity is stronger, and the sputtering equipment is safe and reliable.
In order to further ensure reliability, the power supply of the embodiment also solves the problem that L, C filter elements involved in the output rectifying filter circuit need to be less than 1mJ/KW, otherwise if the stored energy is too large, the energy stored in the output filter circuit will continue to damage the coating material and equipment even if the controller stops outputting, and if the power supply does not adopt filter circuits such as LC (inductance, capacitance) and the like, the requirement that ripple voltage is less than 2% RMS cannot be met. The filter circuit LC is used as a power supply, and how to ensure that the energy stored in the LC is quickly discharged when the controller stops outputting after use corresponds to a value of arc energy storage <1mJ/kW, for which the power supply is addressed from two aspects: 1) the working frequency of the power supply is improved to reduce the constant of the filter circuit; 2) and a fast discharge circuit is added at the output end of the power supply, so that the energy storage energy of the energy storage element is indirectly reduced.
Specifically, the inverter circuit of the power supply of this embodiment adopts an LLC topology scheme, and on the basis of the LLC topology scheme, the switching frequency is configured at least up to several hundred kHz or more, so as to reduce the filter circuit constant and also reduce the switching loss.
Although the LLC scheme can reduce the output filter element parameter values, it cannot be implemented without using an LC filter element, and to ensure fast release of energy storage, the power supply adds a discharge loop at the power supply output, specifically by setting the positive output of the output rectifying filter circuit to be connected to the negative output of the output rectifying filter circuit through an electrically controlled switch series resistor R6, where the electrically controlled switch is connected to the controller. When the device is used, after the controller stops outputting, the quick discharging loop is quickly opened, energy in the filtering loop is eliminated, and an electric arc energy storage value is indirectly reduced.
In order to enable the electronic control switch to be turned on and turned off at high frequency, as shown in fig. 1, the electronic control switch is configured as a switching tube Q6, preferably an IGBT tube, to enhance the voltage endurance, wherein a collector of the switching tube Q6 is connected to the positive output end of the output rectifying and filtering circuit, an emitter thereof is connected to the negative output end of the output rectifying and filtering circuit through a resistor R6, and a base thereof is connected to the controller.
Sputtering equipment is easy to strike arc during sputtering, the quality of a process film layer can be damaged by the striking arc, once the hard arc occurs, the arc needs to be rapidly extinguished to prevent the process film from being damaged, and therefore, the hard arc needs to be rapidly detected. In order to further ensure reliability, the power supply of the embodiment also realizes the detection of the hard arc within 3us, and specifically, the hard arc detection of the power supply of the embodiment does not directly detect the hard arc, but indirectly judges the hard arc through the detection of voltage and current.
In order to realize the detection speed of <3 mus, the sampling of the current and the voltage of the power supply is realized by adopting a pure-mode electric circuit, namely, the scheme of resistance sampling, operational amplifier and comparator is adopted, instead of adopting a Hall voltage and current sensor detection mode. The sampling circuit has the same structure, and only the difference between more and less sampling resistors is shown in fig. 4 as an illustration in this embodiment.
Specifically, the sampling circuit of output current is including sampling resistance, first difference operational amplifier, first follower, sampling resistance is established ties in output rectifier filter circuit positive output end, two input ends of first difference operational amplifier are connected respectively in sampling resistance both ends, first difference operational amplifier's output warp first follower is connected to the controller. The sampling circuit of the output voltage comprises a second differential operational amplifier and a second follower, two input ends of the second differential operational amplifier are respectively connected with two output ends of the output rectifying and filtering circuit, and the output end of the second differential operational amplifier is connected to the controller through the second follower.
After the power supply has a hard arc, the output current can be increased sharply, and the output voltage is reduced sharply under constant power, so that whether the hard arc occurs can be judged by detecting the voltage and/or the current. In this embodiment, if the controller detects that the output current increases sharply or that the output voltage decreases sharply, the controller stops the output of the high-power sputtering power supply and drives the electronic control switch to be closed, so as to quickly discharge the energy stored in the filter inductor and the capacitor, thereby preventing the process film from being further damaged by the energy stored in the power supply.
The power supply of the present embodiment has the following advantages:
1. and the PFC rectification is adopted, so that the power factor of the sputtering power supply network side is improved, and the harmonic pollution of the power network is reduced.
2. By adopting the LLC mode, the switching loss is reduced, and the power output efficiency is improved.
3. The output end adopts a rapid discharge mode, the problem that the energy storage of the electric arc is less than 1mJ/KW is ingeniously solved, and meanwhile, the filtering effect during normal output is not influenced.
4. And a double closed-loop control mode is adopted, so that the response speed of PID regulation is improved, and the voltage after ignition voltage is skillfully and quickly switched to a safe voltage range.
The above embodiments are merely some preferred embodiments of the present invention, and those skilled in the art can make various alternative modifications and combinations of the above embodiments based on the technical solution of the present invention and the related teaching of the above embodiments.
Claims (10)
1. A high-power sputtering power supply is characterized in that:
the power supply comprises a rectifying circuit, a controllable H-bridge inverter circuit, an isolation boosting transformer, an output rectifying filter circuit and a controller, wherein the rectifying circuit, the controllable H-bridge inverter circuit, the isolation boosting transformer, the output rectifying filter circuit and the controller are sequentially and electrically connected;
further comprising a computer storage medium storing a computer program that when executed by the controller performs the steps of:
detecting the output voltage and the output current of the output rectifying and filtering circuit in real time;
taking the product of the output voltage and the output current as output power, and obtaining a voltage effective value by a PI regulator according to the difference value of the output power and a target power value;
and regulating the difference value of the voltage effective value and the output voltage by a PI regulator to obtain the PWM modulation wave for controlling the on-off of each switching tube in the controllable H-bridge inverter circuit.
2. The high power sputtering power supply according to claim 1, wherein: the controllable H-bridge inverter circuit adopts an LLC mode.
3. The high power sputtering power supply according to claim 2, wherein:
the positive output end of the output rectifying and filtering circuit is connected to the negative output end of the output rectifying and filtering circuit through an electric control switch series resistor R6, and the electric control switch is connected with the controller;
and the controller drives the electric control switch to be closed after the high-power sputtering power supply stops outputting.
4. A high power sputtering power supply according to claim 3, wherein: the controllable H-bridge inverter circuit works at least at a switching frequency more than hundreds of kHz, the electric control switch is a switching tube Q6, the collector of the switching tube Q6 is connected with the positive output end of the output rectifying and filtering circuit, the emitter of the switching tube Q6 is connected with the negative output end of the output rectifying and filtering circuit through a resistor R6, and the base of the switching tube Q6 is connected with the controller.
5. A high power sputtering power supply according to claim 3, wherein: and if the controller detects that the output current is increased sharply or the output voltage is reduced sharply, the controller stops the output of the high-power sputtering power supply and drives the electric control switch to be closed.
6. The high power sputtering power supply according to claim 5, wherein: the sampling circuit of the output current and/or the output voltage is a pure mode circuit.
7. The high power sputtering power supply according to claim 6, wherein: the sampling circuit of the output current comprises a sampling resistor, a first differential operational amplifier and a first follower, wherein the sampling resistor is connected with the positive output end of the output rectifying and filtering circuit in series, two input ends of the first differential operational amplifier are respectively connected with two ends of the sampling resistor, and the output end of the first differential operational amplifier is connected to the controller through the first follower.
8. The high power sputtering power supply according to claim 6, wherein: the sampling circuit of the output voltage comprises a second differential operational amplifier and a second follower, two input ends of the second differential operational amplifier are respectively connected with two output ends of the output rectifying and filtering circuit, and the output end of the second differential operational amplifier is connected to the controller through the second follower.
9. The high power sputtering power supply according to claim 1, wherein: the rectification circuit is a 6-pulse PFC rectification circuit.
10. The high power sputtering power supply according to claim 1, wherein: the primary-secondary side ratio of the isolation boosting transformer is 1: 3.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111666013.9A CN114337302A (en) | 2021-12-30 | 2021-12-30 | High-power sputtering power supply |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202111666013.9A CN114337302A (en) | 2021-12-30 | 2021-12-30 | High-power sputtering power supply |
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| CN114337302A true CN114337302A (en) | 2022-04-12 |
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010130866A (en) * | 2008-12-01 | 2010-06-10 | Chuo Seisakusho Ltd | Direct current power supply apparatus |
| CN102570853A (en) * | 2010-12-20 | 2012-07-11 | 西安高度电子科技有限公司 | Constant-power-output magnetron sputtering coating power supply |
| CN206820644U (en) * | 2017-03-17 | 2017-12-29 | 广州视源电子科技股份有限公司 | Power supply output control circuit and power circuit |
| CN107888062A (en) * | 2017-11-02 | 2018-04-06 | 湖北三江航天万峰科技发展有限公司 | A kind of high-power corona discharge devices |
-
2021
- 2021-12-30 CN CN202111666013.9A patent/CN114337302A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010130866A (en) * | 2008-12-01 | 2010-06-10 | Chuo Seisakusho Ltd | Direct current power supply apparatus |
| CN102570853A (en) * | 2010-12-20 | 2012-07-11 | 西安高度电子科技有限公司 | Constant-power-output magnetron sputtering coating power supply |
| CN206820644U (en) * | 2017-03-17 | 2017-12-29 | 广州视源电子科技股份有限公司 | Power supply output control circuit and power circuit |
| CN107888062A (en) * | 2017-11-02 | 2018-04-06 | 湖北三江航天万峰科技发展有限公司 | A kind of high-power corona discharge devices |
Non-Patent Citations (1)
| Title |
|---|
| 蔡伟谦等: "共高频交流母线的电能路由器直流端口控制策略", 《电网技术》 * |
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Application publication date: 20220412 |