Pulse sputtering power supplies and semiconductor process equipment

Abstract

This application relates to a pulsed sputtering power supply and semiconductor process equipment. The pulsed sputtering power supply includes a power supply voltage module, a boost module, a reverse voltage module, and a switching module. The input terminal of the power supply voltage module is connected to an AC power source to obtain a first voltage and provide it to the switching module. The boost module boosts the first voltage and provides a second voltage to the switching module. The reverse voltage module reverses the first voltage and provides a third voltage to the switching module. The control terminal of the switching module receives a control signal to switch the switching state of the switching module based on the control signal. The output terminal of the switching module provides a first voltage, a second voltage, or a third voltage to the outside based on the switching state. The power supply voltage module, boost module, and reverse voltage module all have energy storage capacitors. This pulsed sputtering power supply solves the problem of limited reverse voltage time.

Description

Technical Field

[0001] This application relates to the field of power supply technology, and in particular to a pulsed sputtering power supply and semiconductor process equipment. Background Technology

[0002] Traditional DC and RF sputtering methods in thin film deposition suffer from problems such as low deposition rate, low target utilization, easy generation of film stress and structural defects, limited thickness and composition uniformity over large areas, and low power utilization efficiency of insulating target charging effect (DC) or RF. At the same time, the process is susceptible to plasma instability, target poisoning and fluctuations in reaction atmosphere, making it difficult to guarantee film quality and repeatability. Therefore, pulsed sputtering power supplies have emerged.

[0003] Pulsed sputtering power supplies are a type of power source specifically designed for physical vapor deposition (PVD) processes such as magnetron sputtering. Taking magnetron sputtering as an example, it involves applying a voltage to a target within a vacuum chamber, causing ions in the plasma to bombard the target surface, sputtering atoms or molecules onto a substrate to form a thin film. In magnetron sputtering, continuously applying a negative DC high voltage to the target can easily lead to problems such as target poisoning, arc discharge, and film defects. To address these issues, pulsed sputtering power supplies can improve the plasma state through pulsed drive and a reverse phase.

[0004] However, in related pulse sputtering power supplies, the back pressure duration is fixed or set according to a fixed back pressure ratio, thus limiting the duty cycle. Therefore, a pulse sputtering power supply that can solve the problem of limited back pressure duration is needed. Utility Model Content

[0005] Therefore, it is necessary to provide a pulsed sputtering power supply and semiconductor process equipment that solves the problem of limited reverse voltage time.

[0006] A phase converter includes: a power supply voltage module, a boost module, an inverting module, and a switching module;

[0007] The input terminal of the power supply voltage module is connected to an AC power source, and the output terminal of the power supply voltage module is connected to the first input terminal of the switch module to obtain a first voltage and provide it to the switch module.

[0008] The input terminal of the boost module is connected to the output terminal of the power supply voltage module, and the output terminal of the boost module is connected to the second input terminal of the switch module, for boosting the first voltage and providing a second voltage to the switch module;

[0009] The input terminal of the reverse voltage module is connected to the output terminal of the power supply voltage module, and the output terminal of the reverse voltage module is connected to the third input terminal of the switch module, for reversing the first voltage and providing a third voltage to the switch module;

[0010] The control terminal of the switch module receives a control signal, and the switch state of the switch module is switched based on the control signal; the output terminal of the switch module provides a first voltage, a second voltage, or a third voltage to the outside based on the switch state.

[0011] The power supply voltage module, the boost module, and the reverse voltage module are all equipped with energy storage capacitors.

[0012] In one embodiment, the power supply voltage module includes a high-frequency isolation rectifier module and a filter module; the output terminal of the high-frequency isolation rectifier module is connected to the input terminal of the filter module, and the output terminal of the filter module is connected to the first input terminal of the switching module, wherein...

[0013] The input terminal of the high-frequency isolation rectifier module is connected to an AC power supply, which is used to perform high-frequency isolation rectification on the AC power supply and output a second DC voltage.

[0014] The filtering module is used to filter the second DC voltage and output the first voltage.

[0015] In one embodiment, the high-frequency isolated rectifier module includes a converter circuit and an isolated rectifier circuit. The output terminal of the converter circuit is connected to the input terminal of the isolated rectifier circuit, and the output terminal of the isolated rectifier circuit is connected to the input terminal of the filter module.

[0016] The input terminal of the converter circuit is connected to the AC power supply, which is used to rectify the AC power supply to obtain a first DC voltage, and to invert the first DC voltage to output a high-frequency AC voltage.

[0017] The isolation rectifier circuit is used to isolate and rectify the high-frequency AC voltage and output a second DC voltage.

[0018] In one embodiment, the converter circuit includes a first rectifier circuit and an inverter circuit, wherein the output terminal of the first rectifier circuit is connected to the input terminal of the inverter circuit, and the output terminal of the inverter circuit is connected to the input terminal of the isolation rectifier circuit.

[0019] The first rectifier circuit is used to connect to the AC power supply and rectify the AC power supply to obtain a first DC voltage;

[0020] The inverter circuit is used to perform high-frequency inversion on the first DC voltage and output a high-frequency AC voltage.

[0021] In one embodiment, the isolation rectifier circuit includes an isolation transformer and a second rectifier circuit. The input terminal of the isolation transformer is connected to the output terminal of the converter circuit, and the output terminal of the isolation transformer is connected to the input terminal of the second rectifier circuit.

[0022] The isolation transformer is used to isolate and transform the high-frequency AC voltage.

[0023] The second rectifier circuit is used to rectify the voltage after the isolation transformer and output a second DC voltage.

[0024] In one embodiment, the filtering module includes a first inductor and a first energy storage capacitor. One end of the first inductor is connected to the positive terminal of the first energy storage capacitor, the other end of the first inductor is connected to the first output terminal of the high-frequency isolation rectifier module, and the negative terminal of the first energy storage capacitor is connected to the second output terminal of the high-frequency isolation rectifier module.

[0025] In one embodiment, the switching module includes a first switch, a second switch, a third switch, and a third diode. The drain of the first switch is connected to the positive terminal of the boost module, the source of the first switch is connected to the drain of the second switch, the source of the second switch is connected to the drain of the third switch, and the source of the third switch is connected to the cathode of the reverse voltage module. In the power supply voltage module, the positive terminal of the first energy storage capacitor is connected to the anode of the third diode, the anode of the third diode is connected to the drain of the second switch, and the negative terminal of the first energy storage capacitor is connected to the source of the second switch. Control signals are connected to the control terminals of the first switch, the second switch, and the third switch.

[0026] In one embodiment, the boost module includes a second inductor, a fourth switch, a first diode, and a second energy storage capacitor. One end of the second inductor is connected to the positive terminal of the first energy storage capacitor in the power supply voltage module, and the other end is connected to the anode of the first diode. The cathode of the first diode is connected to the positive terminal of the second energy storage capacitor and the drain of the first switch in the switch module. The negative terminal of the second energy storage capacitor is connected to the negative terminal of the first energy storage capacitor. The drain of the fourth switch is connected to the connection point of the second inductor and the first diode, and the source of the fourth switch is connected to the connection point of the second energy storage capacitor and the first energy storage capacitor.

[0027] In one embodiment, the reverse voltage module includes a third inductor, a second diode, a fifth switch, and a third energy storage capacitor. The drain of the fifth switch is connected to the positive terminal of the first energy storage capacitor. The source and drain of the fifth switch are connected to the cathode of the second diode. The anode of the second diode is connected to the negative terminal of the third energy storage capacitor. The positive terminal of the third energy storage capacitor is connected to the negative terminal of the first energy storage capacitor. One end of the third inductor is connected to the connection point between the source of the fifth switch and the cathode of the second diode. The other end of the third inductor is connected to the connection point between the positive terminal of the third energy storage capacitor and the negative terminal of the first energy storage capacitor. The positive terminal of the third energy storage capacitor is connected to the source of the third switch.

[0028] In one embodiment, the state of the switch module includes at least one of the following states: a first state where the first switch is on and the second switch is on and the third switch is off; a second state where the first switch is off and the second switch is on and the third switch is off; a third state where the first switch is off and the second switch is off and the third switch is on; and a fourth state where the first switch is off and the second switch is off and the third switch is off.

[0029] The pulsed sputtering power supply provides the second voltage to the outside in the first state, provides the first voltage to the outside in the second state, and provides the third voltage to the outside in the third state.

[0030] A semiconductor process apparatus, comprising the pulse sputtering power supply and the semiconductor process apparatus body as described in any one of the preceding claims.

[0031] The aforementioned pulse sputtering power supply and semiconductor process equipment, by incorporating energy storage capacitors in the power supply voltage module, boost module, and reverse voltage module, can prevent inductors from saturating due to continuously increasing energy storage. Furthermore, the inclusion of boost and reverse voltage modules in the pulse sputtering power supply allows for rapid changes in the magnitude and direction of the output current. This capacitor-based energy storage commutation method solves the problem of limited reverse voltage time in traditional pulse sputtering power supplies. Moreover, in semiconductor processes, the duty cycle of the forward pulse and the duration of the reverse voltage can be set according to actual needs, thereby improving semiconductor production yield. Attached Figure Description

[0032] To more clearly illustrate the technical solutions in the embodiments of this application or the conventional technology, the drawings used in the description of the embodiments or the conventional technology will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0033] Figure 1 This is a pulse sputtering power supply module structure according to one embodiment;

[0034] Figure 2 for Figure 1 A modular structure of a medium power supply voltage module;

[0035] Figure 3 A power supply voltage module as described in a specific embodiment;

[0036] Figure 4 This is a partial circuit diagram of a pulsed sputtering power supply in a specific embodiment;

[0037] Figure 5 The voltage and current waveforms output by the pulse sputtering power supply in a specific embodiment are shown.

[0038] Figure 6 This is a boost module in a specific embodiment;

[0039] Figure 7 This is a reverse pressure module in a specific embodiment;

[0040] Figure 8 This is a pulsed sputtering power supply in a specific embodiment;

[0041] Figure 9 This is a voltage and current waveform output by the pulse sputtering power supply in a specific embodiment.

[0042] Explanation of reference numerals in the attached diagram: 100, power supply voltage module; 200, boost module; 300, reverse voltage module; 400, switch module; 102, high-frequency isolation rectifier module; 104, filter module. Detailed Implementation

[0043] To facilitate understanding of this application, a more complete description will be provided below with reference to the accompanying drawings, which illustrate embodiments of the present application. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of this application will be thorough and complete.

[0044] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0045] It is understood that the terms "first," "second," etc., used herein may be used to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish one element from another. For example, without departing from the scope of this application, a first resistor may be referred to as a second resistor, and similarly, a second resistor may be referred to as a first resistor. Both the first resistor and the second resistor are resistors, but they are not the same resistor.

[0046] It is understood that the term "connection" in the following embodiments should be understood as "electrical connection," "communication connection," etc., if the connected circuits, modules, units, etc., have electrical signal or data transmission with each other.

[0047] It is understandable that "at least one" refers to one or more, and "multiple" refers to two or more. "At least a part of an element" refers to part or all of an element.

[0048] When used herein, the singular forms of “a,” “an,” and “the” may also include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising / including” or “having,” etc., specify the presence of the stated features, wholes, steps, operations, components, parts, or combinations thereof, but do not preclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts, or combinations thereof. Meanwhile, the term “and / or” as used in this specification includes any and all combinations of the associated listed items.

[0049] Magnetron sputtering is a common method for thin film fabrication. It involves applying a voltage to a target within a vacuum chamber, causing ions in the plasma to bombard the target surface, sputtering atoms or molecules onto a substrate to form a thin film. Addressing the technical limitations of traditional DC or RF sputtering, pulsed sputtering power supplies convert the output of a DC or intermediate frequency power supply into periodic positive and negative pulses (or zero-potential gaps), rapidly switching polarity or interrupting the discharge. This neutralizes the charge on the target surface during the reverse pulse, thereby suppressing charge accumulation.

[0050] However, pulsed sputtering voltage technologies, such as AE's pulsed sputtering power supply, use inductors for commutation to switch between pulse and reverse voltage output. During the reverse voltage output phase, energy is stored in the inductor, and then output to the load during the pulse phase. If the reverse voltage duration in this circuit structure is too long, the continuously increasing inductor current will cause inductor saturation, limiting the reverse voltage duration and consequently the duty cycle.

[0051] To address the limitation of back pressure duration in related technologies, a pulsed sputtering power supply is proposed.

[0052] like Figure 1As shown, a pulsed sputtering power supply in one embodiment includes: a power supply voltage module 100, a boost module 200, a reverse voltage module 300, and a switching module 400; the input terminal of the power supply voltage module 100 is connected to an AC power source, and the output terminal of the power supply voltage module 100 is connected to the first input terminal of the switching module 400 to obtain a first voltage and provide the first voltage to the switching module 400; the input terminal of the boost module 200 is connected to the output terminal of the power supply voltage module 100, and the output terminal of the boost module 200 is connected to the second input terminal of the switching module 400 to boost the first voltage and provide it to the switching module 400. The first voltage is provided by the first voltage module 100; the input terminal of the reverse voltage module 300 is connected to the output terminal of the power supply voltage module 100, and the output terminal of the reverse voltage module 300 is connected to the third input terminal of the switch module 400, which is used to reverse the first voltage and provide the third voltage to the switch module 400; the control terminal of the switch module 400 is connected to the control signal, and the switching state of the switch module 400 is switched based on the control signal; the output terminal of the switch module 400 provides the first voltage, the second voltage, or the third voltage to the outside based on the switching state; the power supply voltage module 100, the boost module 200, and the reverse voltage module 300 are all equipped with energy storage capacitors.

[0053] Understandably, a pulse cycle of a pulsed sputtering power supply can include a forward pulse phase (also called the normal sputtering phase), a reverse pulse phase, and a zero-level phase. During the normal sputtering phase, the target is the negative electrode, and high-energy positive ions bombard the target surface, resulting in sputtering. During the reverse pulse phase, the power supply briefly changes the target potential to a positive value. The reverse voltage can be understood as the voltage applied to the target in the opposite direction within one pulse cycle. Its purpose is to change the target from its original negative electrode to a positive electrode in a short time, thereby altering the potential relationship between the target surface and the plasma. In other words, the reverse voltage in a pulsed sputtering power supply is a brief forward voltage applied to the target within one pulse cycle, used to eliminate charge accumulation on the target surface, suppress arcing, stabilize the plasma, and improve deposition quality.

[0054] Because the inductor energy is limited when using inductor energy storage for commutation, it is necessary to provide the reverse voltage required for turn-off while achieving magnetization / demagnetization balance within one cycle. This limits the duty cycle of the corresponding pulse sputtering power supply and restricts the reverse voltage time. Therefore, a pulse sputtering power supply with capacitor energy storage has been proposed.

[0055] The power supply voltage module 100 can rectify, invert, and filter the connected AC power supply to output a stable first voltage, thus providing a stable initial voltage. The power supply voltage module 100 can be, but is not limited to, existing structures; the structure of the power supply voltage module 100 only needs to be able to output a stable first voltage.

[0056] The boost module 200 is connected to the power supply voltage module 100 and the switching module 400. It can be understood that the boost module 200 can boost the input first voltage to a higher second voltage through energy storage and release via an energy storage capacitor, to meet the high power output required in the sputtering stage. It can also be understood that boosting the first voltage to the second voltage, which can also be called the pulse voltage, is to ensure that the output current flowing from the pulse sputtering power supply to the chamber can still quickly rise to Iout despite the influence of long wires and inductive components such as the output inductor. It should be noted that the chamber can be a vacuum chamber, reaction chamber, or other experimental / equipment component that needs to be energized; Iout is the output current flowing to the chamber. Taking a coating equipment as an example, the chamber can be a vacuum-sealed space where coating is performed. The boost module 200 can be one or more of a boost circuit or a transformer-isolated boost structure. For example, the boost module 200 can be a boost circuit, which is a DC-DC converter circuit that boosts a lower first DC voltage to a higher first DC voltage. The circuit corresponding to the boost module 200 can include components such as switching elements, inductors, diodes, and output capacitors.

[0057] The reverse voltage module 300 is connected to the power supply voltage module 100 and the switching module 400. The reverse voltage module 300 converts the input first voltage into a third voltage in negative form, used to reverse bias the target material during sputtering, thereby suppressing target poisoning, reducing arc discharge, and improving plasma stability during the reverse voltage stage. The circuit corresponding to the reverse voltage module 300 may include components such as switching elements, inductors, diodes, and output capacitors.

[0058] The switching module 400 can be, but is not limited to, a multiplexing circuit composed of MOSFETs. The control terminal of the switching module 400 can respond to an input control signal to switch different voltage input channels, providing a first voltage, a second voltage, or a third voltage to the external circuit through the energy storage capacitor in the pulse sputtering power supply. Taking semiconductor film deposition as an example, for one pulse cycle, the voltage signals corresponding to the first and second voltages are output during the normal sputtering phase of the pulse cycle, while the voltage signal corresponding to the third voltage is output during the reverse pulse phase of the pulse cycle.

[0059] For example, by providing energy storage capacitors in the power supply voltage module 100, the boost module 200, and the reverse voltage module 300, and connecting the switching module 400 to the power supply voltage module 100, the boost module 200, the reverse voltage module 300, and an external load, the switching module 400 can switch different voltage input channels according to the control signal. It can provide a first voltage to the external load through the first energy storage capacitor in the power supply voltage module 100, provide a second voltage to the external load through the second energy storage capacitor in the boost module 200, or provide a third voltage to the external load through the third energy storage capacitor in the reverse voltage module 300.

[0060] For example, taking a coating application scenario as an example, within one pulse cycle, a stable first voltage is provided by the power supply voltage module 100. During the sputtering stage, the boost module 200 boosts the first voltage to a second voltage and then switches back to the first voltage to obtain a rapidly rising target preset output current without overshoot. When target poisoning is detected, a control signal triggers the switch module 400 to switch to a third voltage provided by the reverse voltage module 300 to adjust the reverse voltage duration. It can be understood that the voltage amplitudes and durations of the first, second, and third voltages can be preset according to actual process requirements.

[0061] The aforementioned pulse sputtering power supply, by incorporating energy storage capacitors in the power supply voltage module 100, boost module 200, and reverse voltage module 300, avoids inductor saturation caused by the continuous increase in inductor energy storage current. Furthermore, the presence of boost module 200 and reverse voltage module 300 allows for rapid current commutation by changing the current flow direction. This capacitor-based energy storage commutation method solves the problem of limited reverse voltage time in traditional pulse sputtering power supplies. Moreover, in semiconductor processes, the duty cycle of the forward pulse and the duration of the reverse voltage can be set according to actual needs, improving semiconductor production yield.

[0062] like Figure 2 As shown, the power supply voltage module 100 includes a high-frequency isolation rectifier module 102 and a filter module 104. The output terminal of the high-frequency isolation rectifier module 102 is connected to the input terminal of the filter module 104, and the output terminal of the filter module 104 is connected to the first input terminal of the switch module 400. The input terminal of the high-frequency isolation rectifier module 102 is connected to an AC power supply for high-frequency isolation rectification of the AC power supply to output a second DC voltage. The filter module 104 is used to filter the second DC voltage to output a first voltage.

[0063] It is understandable that the high-frequency isolation rectifier module 102 can convert the AC power supply into DC power through a rectifier bridge and output it to the rectifier circuit, which then outputs a second DC voltage. The high-frequency isolation rectifier module 102 can be a circuit structure that can convert AC power into DC power, which will not be described in detail here. The filter module 104 can be a π-type filter structure or an LC low-pass filter.

[0064] In this method, the power supply voltage module 100 includes a high-frequency isolation rectifier module 102 and a filter module 104. The output terminal of the high-frequency isolation rectifier module 102 is connected to the input terminal of the filter module 104, and the output terminal of the filter module 104 is connected to the first input terminal of the switch module 400. The high-frequency isolation rectifier module 102 performs transformer rectification on the AC power supply to output a second DC voltage, and the filter module 104 filters the second DC voltage to output a first voltage, thereby improving the voltage output stability.

[0065] Furthermore, the high-frequency isolation rectifier module 102 includes a converter circuit and an isolation rectifier circuit. The output terminal of the converter circuit is connected to the input terminal of the isolation rectifier circuit, and the output terminal of the isolation rectifier circuit is connected to the input terminal of the filter module 104. The input terminal of the converter circuit is connected to an AC power supply to rectify the AC power supply to obtain a first DC voltage, and then inverts the first DC voltage to output a high-frequency AC voltage. The isolation rectifier circuit is used to perform isolation rectification on the high-frequency AC voltage to output a second DC voltage.

[0066] In one exemplary embodiment, the converter circuit includes a first rectifier circuit and an inverter circuit. The output terminal of the first rectifier circuit is connected to the input terminal of the inverter circuit, and the output terminal of the inverter circuit is connected to the input terminal of the isolation rectifier circuit. The first rectifier circuit is used to connect to an AC power source and rectify the AC power source to obtain a first DC voltage. The inverter circuit is used to perform high-frequency inversion on the first DC voltage and output a high-frequency AC voltage.

[0067] The first rectifier circuit can be a rectifier, and the rectifier can be any existing rectifier. For example, the first rectifier circuit can be a single diode circuit or a circuit including two diodes. This embodiment uses a single diode circuit as an example to illustrate that the AC power supply voltage is rectified by connecting the single diode circuit to the AC power supply to obtain the first DC voltage. The first rectifier circuit can be identified by "Rec".

[0068] An inverter circuit can be composed of multiple metal-oxide-semiconductor field-effect transistors (MOSFETs). For example, an inverter (INV) can be composed of four MOSFETs. The connection between the four MOSFETs can be achieved using existing methods, which will not be elaborated here. A MOSFET includes a gate, drain, and source, and an inherent body diode between the drain and source. It is understood that by adjusting the inverter's duty cycle, a first voltage can be adjusted to control the output power, voltage, and current.

[0069] In one exemplary embodiment, the isolation rectifier circuit includes an isolation transformer and a second rectifier circuit. The input terminal of the isolation transformer is connected to the output terminal of the converter circuit, and the output terminal of the isolation transformer is connected to the input terminal of the second rectifier circuit. The isolation transformer is used to isolate and transform the high-frequency AC voltage and output the isolated and transformed voltage. The second rectifier circuit is used to rectify the isolated and transformed voltage and output a second DC voltage.

[0070] The isolation transformer can be any existing transformer that supports isolation transformation. Details regarding isolation transformers will not be elaborated upon here. The second rectifier circuit may include a rectifier bridge, which can be composed of four diodes connected in a specific bridge structure, such as four diodes interconnected in a diamond (or square) shape. For example, the second rectifier circuit includes diodes D1, D2, D3, and D4, with the cathodes of D1 and D3 connected, the anodes of D1 and D2 connected, the anodes of D2 and D4 connected, and the cathode of D4 connected to the anode of D3. The output terminal of this second rectifier circuit is connected to the input terminal of the filter module 104. Taking the filter module 104 as an LC filter module 104, the intermediate node connecting D1 and D3 is connected to the first inductor of the filter module 104 in the power supply voltage module 100, and the intermediate node connecting D2 and D4 is connected to the negative terminal of the first energy storage capacitor in the LC filter module 104.

[0071] The following is a circuit structure of a filter module 104 in an exemplary embodiment. The filter module 104 includes a first inductor and a first energy storage capacitor. One end of the first inductor is connected to the positive terminal of the first energy storage capacitor, and the other end of the first inductor is connected to the first output terminal of the high-frequency isolation rectifier module 102. The negative terminal of the first energy storage capacitor is connected to the second output terminal of the high-frequency isolation rectifier module 102. The first energy storage capacitor can store the filtered stable voltage. Through this filter module 104, a second DC voltage can be filtered to obtain a stable first voltage.

[0072] In one exemplary embodiment, such as Figure 3 As shown, a structural schematic diagram of the power supply voltage module 100 is provided. The power supply voltage module 100 includes a first rectifier circuit, an inverter circuit, an isolation transformer, a second rectifier circuit, and a filter module 104. The second rectifier circuit includes diodes D1, D2, D3, and D4. The filter module 104 includes a first inductor L1 and a first energy storage capacitor C1. The connection method of the power supply voltage module 100 can be achieved in the manner defined above, which will not be elaborated here. A stable first voltage can be obtained through the power supply voltage module 100, and the first energy storage capacitor stores energy to determine the main power supply for sputtering.

[0073] It is understood that the switch module 400 can provide a first voltage, a second voltage, or a third voltage to the outside by switching different switch states. In an exemplary embodiment, a structural schematic diagram of the switch module 400 is provided. The switch module 400 includes a first switch, a second switch, a third switch, and a third diode. The drain of the first switch is connected to the output terminal of the boost module 200; that is, the drain of the first switch can be connected to the positive terminal of the second energy storage capacitor in the boost module 200, the source of the first switch is connected to the drain of the second switch, the source of the second switch is connected to the drain of the third switch, and the source of the third switch is connected to the cathode of the reverse voltage module 300. In the power supply voltage module 100, the positive terminal of the first energy storage capacitor is connected to the anode of the third diode, the anode of the third diode is connected to the drain of the second switch, and the negative terminal of the first energy storage capacitor is connected to the source of the second switch. Control signals are connected to the control terminals of the first switch, the second switch, and the third switch.

[0074] In this circuit, the control terminals of the first switch, the second switch, and the third switch can each be their respective gates. Based on the above-described switch module 400, the switching states of the switch module 400 can be switched. The first switch, the second switch, and the third switch can all be MOSFETs, and can be represented as MOS1, MOS2, and MOS3, respectively. MOS2 can be used to control the sputtering time and reverse voltage time in one pulse cycle, MOS3 can be used to control the reverse voltage application time, and MOS1 can be used to control the voltage amplitude and output time of the first voltage.

[0075] The states of the switch module 400 include at least one of the following states: a first state where the first switch is on and the second switch is on and the third switch is off; a second state where the first switch is off and the second switch is on and the third switch is off; a third state where the first switch is off and the second switch is off and the third switch is on; and a fourth state where the first switch is off and the second switch is off and the third switch is off. In the first state, the pulse sputtering power supply provides a second voltage to the outside; in the second state, it provides a first voltage to the outside; in the third state, it provides a third voltage to the outside; and in the fourth state, it outputs a zero level.

[0076] Based on the aforementioned switch module 400, a partial circuit diagram of a pulsed sputtering power supply in one embodiment is provided, as follows: Figure 4As shown, the drain of the first switch MOS1 is connected to the positive terminal of the first energy storage capacitor, the source of the first switch MOS1 is connected to the drain of the second switch MOS2, the negative terminals of the first and second energy storage capacitors are connected, the positive terminal of the third energy storage capacitor is connected to the junction of the negative terminals of the first and second energy storage capacitors, the positive terminal of the first energy storage capacitor is connected to the anode of the third diode, the cathode of the third diode is connected to the junction of the source of the first switch MOS1 and the drain of the second switch MOS2, the source of the second switch MOS2 is connected to the drain of the third switch MOS3, and the source of the third switch MOS3 is connected to the negative terminal of the third energy storage capacitor in the reverse voltage module. One end of the output inductor Lout is connected to the junction of the source of the second switch MOS2 and the drain of the third switch MOS3, the other end of the output inductor Lout is connected to one end of the long cable Line, the other end of the long cable Line is connected to the load equivalent resistance Rload, and the other end of the load equivalent resistance Rload is connected to the junction of the negative terminals of the first, second, and third energy storage capacitors. The first energy storage capacitor can output the first voltage, the second energy storage capacitor can output the second voltage, and the third energy storage capacitor can output the third voltage.

[0077] based on Figure 4 The circuit structure shown can output [data] by controlling the three switches in the switching module 400 according to a certain timing sequence. Figure 5 The voltage and current waveforms shown represent one pulse cycle. In the first time period, controlling the first switch to be on, the second switch to be on, and the third switch to be off, puts the switching module 400 in a first state, outputting a second voltage. In the second time period, controlling the first switch to be off, the second switch to be on, and the third switch to be off, puts the switching module 400 in a second state, outputting a first voltage. In the third time period, controlling the first switch to be off, the second switch to be off, and the third switch to be on, puts the switching module 400 in a third state, outputting a third voltage. Controlling the first switch to be off, the second switch to be off, and the third switch to be off, puts the switching module 400 in a fourth state, outputting a zero level. The first and second time periods are positive pulse phases, while the third and fourth time periods are negative pulse phases. It can be understood that the entire negative pulse phase may consist only of the third time period.

[0078] In an exemplary embodiment, a specific structure of a boost module 200 is provided. One end of the second inductor is connected to the positive terminal of the first energy storage capacitor in the power supply voltage module 100, and the other end is connected to the anode of the first diode. The cathode of the first diode is connected to the positive terminal of the second energy storage capacitor and the drain of the first switch in the switch module 400. The cathode of the second energy storage capacitor is connected to the cathode of the first energy storage capacitor. The drain of the fourth switch is connected to the connection point of the second inductor and the first diode, and the source of the fourth switch is connected to the connection point of the second energy storage capacitor and the first energy storage capacitor.

[0079] like Figure 6 As shown, the boost module 200 includes a second inductor, a fourth switch, a first diode, and a second energy storage capacitor. The second inductor is represented by L2, the fourth switch by MOS4, and the first diode by D5. The second energy storage capacitor is used to output a second voltage Vboost, and the first energy storage capacitor is used to output a first voltage Vprocess. Based on the circuit of the boost module 200 shown in the figure, the first voltage output by the first energy storage capacitor is boosted by L2 and MOS4 to obtain the second voltage. The charge corresponding to the second voltage is stored in the second energy storage capacitor so that the voltage across the second energy storage capacitor is maintained at the second voltage. Based on this, combined with the aforementioned switch module 400, by controlling the first switch to be turned on, the second switch to be turned on, and the third switch to be turned off, the second voltage is output. For any type of load, the output current of the pulse sputtering power supply can be stabilized to the target value in a very short time.

[0080] In an exemplary embodiment, a specific structure of a reverse voltage module 300 is provided. The reverse voltage module 300 includes a third inductor, a second diode, a fifth switch, and a third energy storage capacitor. The drain of the fifth switch is connected to the positive terminal of the first energy storage capacitor in the power supply voltage module 100. The source of the fifth switch is connected to the cathode of the second diode. The anode of the second diode is connected to the negative terminal of the third energy storage capacitor. The positive terminal of the third energy storage capacitor is connected to the negative terminal of the first energy storage capacitor. One end of the third inductor is connected to the connection point between the source of the fifth switch and the cathode of the second diode. The other end of the third inductor is connected to the connection point between the positive terminal of the third energy storage capacitor and the negative terminal of the first energy storage capacitor. The positive terminal of the third energy storage capacitor is connected to the source of the third switch in the switch module 400.

[0081] The third inductor, the second diode, the fifth switch, and the third energy storage capacitor can be existing components, which will not be described in detail here.

[0082] like Figure 7As shown, the reverse voltage module 300 includes a third inductor, a second diode, a fifth switch, and a third energy storage capacitor. The third inductor is represented by L3, the fifth switch by MOS5, and the second diode by D6. The third energy storage capacitor is used to output a third voltage Vreverse, and the first energy storage capacitor is used to output a first voltage Vprocess. Based on the circuit of the boost module 200 shown, the first voltage output by the first energy storage capacitor is reverse-voltaged using MOS5 and L3 to obtain a third voltage that is opposite to the first voltage. The charge corresponding to the third voltage is stored in the third energy storage capacitor to maintain the third voltage across the third energy storage capacitor. Based on this, combined with the aforementioned switch module 400, by controlling the first switch to open, the second switch to open, and the third switch to open, the third voltage is output to eliminate accumulated charge on the target surface, thereby preventing arcing, improving discharge stability, and improving thin film quality.

[0083] In one exemplary embodiment, a pulsed sputtering power supply is provided, such as Figure 8As shown, the pulsed sputtering power supply includes a first rectifier circuit, an inverter circuit, an isolation transformer, a second rectifier circuit, a filter module 104, a boost module 200, a reverse voltage module 300, and a switch module 400. The second rectifier circuit includes diodes D1, D2, D3, and D4. The filter module 104 includes a first inductor L1 and a first energy storage capacitor C1. The boost module 200 includes a second inductor, a fourth switch, a first diode, and a second energy storage capacitor. The second inductor is represented as L2, the fourth switch as MOS4, and the first diode as D5. The second energy storage capacitor outputs a second voltage Vboost, and the first energy storage capacitor outputs a first voltage Vprocess. The reverse voltage module 300 includes a third inductor, a second diode, a fifth switch, and a third energy storage capacitor. The third inductor is represented as L3, the fifth switch as MOS5, and the second diode as D6. The third energy storage capacitor outputs a third voltage Vreverse. The drain of the first switch MOS1 is connected to the positive terminal of the first energy storage capacitor. The source of the first switch MOS1 is connected to the drain of the second switch MOS2. The negative terminals of the first and second energy storage capacitors are connected. The positive terminal of the third energy storage capacitor is connected to the junction of the negative terminals of the first and second energy storage capacitors. The positive terminal of the first energy storage capacitor is connected to the anode of the diode. The cathode of the diode is connected to the junction of the source of the first switch MOS1 and the drain of the second switch MOS2. The source of the second switch MOS2 is connected to the drain of the third switch MOS3. The source of the third switch MOS3 is connected to the negative terminal of the third energy storage capacitor. One end of the output inductor Lout is connected to the junction of the source of the second switch MOS2 and the drain of the third switch MOS3. The other end of the output inductor Lout is connected to one end of a long cable Line. The other end of the long cable Line is connected to the equivalent load resistance Rload. The other end of the equivalent load resistance Rload is connected to the junction of the negative terminals of the first, second, and third energy storage capacitors.

[0084] Based on the aforementioned pulsed sputtering power supply, the input AC power is rectified by Rec to obtain a first DC voltage, which is then inverted at high frequency by a high-frequency inverter INV. After isolation transformation by an isolation transformer TR, the voltage is rectified again by a rectifier bridge to output a second DC voltage. This second voltage is then filtered by L1C1 to obtain a stable first voltage Vprocess, and the charge corresponding to this first voltage is stored in a first energy storage capacitor C1. Furthermore, the voltage amplitude of the first voltage Vprocess can be adjusted by regulating the duty cycle of INV to control the output power, voltage, and current.

[0085] The first voltage output from the first energy storage capacitor is boosted using L2 and MOS4 to obtain a second voltage. This second voltage is output by controlling the first switch to be on, the second switch to be on, and the third switch to be off. When the output current corresponding to the second voltage reaches a preset target current, the first switch is opened, the second switch is turned on, and the third switch is opened, placing the switching module 400 in a second state and outputting the first voltage. The first voltage output from the first energy storage capacitor is reverse-biased using MOS5 and L3 to obtain a third voltage that is opposite to the first voltage. This third voltage is output by controlling the first switch to be off, the second switch to be off, and the third switch to be on.

[0086] like Figure 9 As shown, it is based on Figure 9 The waveforms of the voltage and current output from the pulse sputtering power supply are shown below. The horizontal axis represents time t, and the vertical axis represents the output voltage or current. Red represents the output voltage Vout, and green represents the output current Iout. One pulse cycle includes a forward pulse phase and a reverse pulse phase. During the forward pulse phase, the duration of the second voltage (the pulse voltage) is determined based on the preset target output current. This can be understood as checking whether the output current rises to the preset target output current Iout to determine the duration of the second voltage Vboost, ensuring the current rises as quickly as possible without overshoot. When the output current reaches the preset target output current, i.e., after ignition is complete, the first voltage is output. In other words, the faster the output current rises to Iout, the better the sputtering consistency. By adjusting the amplitude and duration of the second voltage Vboost through the first switch MOS1, the chamber current can be rapidly raised to Iout without overshoot under various load conditions.

[0087] During the reverse pulse phase, a third voltage is output. Furthermore, a transition phase Tcross between the reverse pulse phase and the forward pulse phase in the next pulse cycle can be set. By setting this transition phase, the safety of the power supply can be ensured.

[0088] Based on such Figure 8 As shown in the pulsed sputtering power supply diagram, ignition can be achieved by adjusting the second voltage Vboost. After ignition is complete, the Vboost ignition voltage is turned off by MOS1, and the power output is maintained by Vprocess. This can be understood as follows: a high voltage is first used to trigger the gas or dielectric breakdown and initiate the discharge (ignition); after the plasma or discharge channel is established (i.e., ignition is complete), the power supply switches to a lower sustaining voltage to enter the stable operation phase. During the ignition process, the output equivalent resistance Rload rapidly decreases when chamber ignition occurs. When ignition occurs, the power supply actively turns off MOS2, cutting off the power output. Energy in the cable is absorbed by the Vreverse capacitor, and a reverse voltage is automatically applied to accelerate the decrease in ignition current.

[0089] The aforementioned pulse sputtering power supply, by incorporating energy storage capacitors in the power supply voltage module 100, boost module 200, and reverse voltage module 300, avoids inductor saturation caused by the continuous increase in inductor energy storage current. Furthermore, the presence of boost module 200 and reverse voltage module 300 allows for rapid changes in the magnitude and direction of the output current. This capacitor-based energy storage commutation method solves the problem of limited reverse voltage time in traditional pulse sputtering power supplies. Moreover, in semiconductor processes, the duty cycle of the forward pulse and the duration of the reverse voltage can be set according to actual needs, improving semiconductor production yield.

[0090] It is understood that the above-mentioned pulse sputtering power supply can also take other forms, and is not limited to the forms already mentioned in the above embodiments, as long as it can achieve the function of solving the back pressure duration limitation.

[0091] In one exemplary embodiment, a semiconductor process apparatus is provided, including a pulsed sputtering power supply as described in any one of the foregoing descriptions and a semiconductor process apparatus body. The semiconductor process apparatus body can refer to the main structural and functional units of a piece of equipment used in semiconductor production, such as a coating equipment body. The pulsed sputtering power supply can provide pulses to the semiconductor process apparatus body to achieve semiconductor production.

[0092] In the description of this specification, references to terms such as "some embodiments," "other embodiments," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative descriptions of the above terms do not necessarily refer to the same embodiments or examples.

[0093] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0094] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these modifications and improvements all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A pulsed sputtering power supply, characterized by, include: Power supply voltage module, boost module, reverse voltage module, and switching module; The input terminal of the power supply voltage module is connected to an AC power source, and the output terminal of the power supply voltage module is connected to the first input terminal of the switch module to obtain a first voltage and provide it to the switch module. The input terminal of the boost module is connected to the output terminal of the power supply voltage module, and the output terminal of the boost module is connected to the second input terminal of the switch module, for boosting the first voltage and providing a second voltage to the switch module; The input terminal of the reverse voltage module is connected to the output terminal of the power supply voltage module, and the output terminal of the reverse voltage module is connected to the third input terminal of the switch module, for reversing the first voltage and providing a third voltage to the switch module; The control terminal of the switch module receives a control signal and switches the switch state of the switch module based on the control signal; the output terminal of the switch module provides a first voltage, a second voltage, or a third voltage to the outside based on the switch state. The power supply voltage module, the boost module, and the reverse voltage module are all equipped with energy storage capacitors.

2. The pulsed sputtering power supply of claim 1, wherein, The power supply voltage module includes a high-frequency isolation rectifier module and a filter module; the output terminal of the high-frequency isolation rectifier module is connected to the input terminal of the filter module, and the output terminal of the filter module is connected to the first input terminal of the switching module. The input terminal of the high-frequency isolation rectifier module is connected to an AC power supply, which is used to perform high-frequency isolation rectification on the AC power supply and output a second DC voltage. The filtering module is used to filter the second DC voltage and output the first voltage.

3. The pulsed sputtering power supply of claim 2, wherein, The high-frequency isolated rectifier module includes a converter circuit and an isolated rectifier circuit. The output terminal of the converter circuit is connected to the input terminal of the isolated rectifier circuit, and the output terminal of the isolated rectifier circuit is connected to the input terminal of the filter module. The input terminal of the converter circuit is connected to the AC power supply, which is used to rectify the AC power supply to obtain a first DC voltage, and to invert the first DC voltage to output a high-frequency AC voltage. The isolation rectifier circuit is used to isolate and rectify the high-frequency AC voltage and output a second DC voltage.

4. The pulsed sputtering power supply of claim 3, wherein, The converter circuit includes a first rectifier circuit and an inverter circuit. The output terminal of the first rectifier circuit is connected to the input terminal of the inverter circuit, and the output terminal of the inverter circuit is connected to the input terminal of the isolation rectifier circuit. The first rectifier circuit is used to connect to the AC power supply and rectify the AC power supply to obtain a first DC voltage; The inverter circuit is used to perform high-frequency inversion on the first DC voltage and output a high-frequency AC voltage.

5. The pulsed sputtering power supply of claim 3, wherein, The isolation rectifier circuit includes an isolation transformer and a second rectifier circuit. The input terminal of the isolation transformer is connected to the output terminal of the converter circuit, and the output terminal of the isolation transformer is connected to the input terminal of the second rectifier circuit. The isolation transformer is used to isolate and transform the high-frequency AC voltage. The second rectifier circuit is used to rectify the voltage after isolation transformation to obtain a second DC voltage.

6. The pulsed sputtering power supply of claim 2, wherein, The filtering module includes a first inductor and a first energy storage capacitor. One end of the first inductor is connected to the positive terminal of the first energy storage capacitor, and the other end of the first inductor is connected to the first output terminal of the high-frequency isolation rectifier module. The negative terminal of the first energy storage capacitor is connected to the second output terminal of the high-frequency isolation rectifier module.

7. The pulsed sputtering power supply of claim 1, wherein, The switching module includes a first switch, a second switch, a third switch, and a third diode. The drain of the first switch is connected to the positive terminal of the boost module, the source of the first switch is connected to the drain of the second switch, the source of the second switch is connected to the drain of the third switch, and the source of the third switch is connected to the cathode of the reverse voltage module. In the power supply voltage module, the positive terminal of the first energy storage capacitor is connected to the anode of the third diode, the anode of the third diode is connected to the drain of the second switch, and the negative terminal of the first energy storage capacitor is connected to the source of the second switch. Control signals are connected to the control terminals of the first switch, the second switch, and the third switch.

8. The pulsed sputtering power supply of claim 1, wherein, The boost module includes a second inductor, a fourth switch, a first diode, and a second energy storage capacitor. One end of the second inductor is connected to the positive terminal of the first energy storage capacitor in the power supply voltage module, and the other end is connected to the anode of the first diode. The cathode of the first diode is connected to the positive terminal of the second energy storage capacitor and the drain of the first switch in the switch module. The negative terminal of the second energy storage capacitor is connected to the negative terminal of the first energy storage capacitor. The drain of the fourth switch is connected to the connection point of the second inductor and the first diode, and the source of the fourth switch is connected to the connection point of the second energy storage capacitor and the first energy storage capacitor.

9. The pulse sputtering power supply according to claim 1, characterized in that, The reverse voltage module includes a third inductor, a second diode, a fifth switch, and a third energy storage capacitor. The drain of the fifth switch is connected to the positive terminal of the first energy storage capacitor in the power supply voltage module. The source of the fifth switch is connected to the cathode of the second diode. The anode of the second diode is connected to the negative terminal of the third energy storage capacitor. The positive terminal of the third energy storage capacitor is connected to the negative terminal of the first energy storage capacitor. One end of the third inductor is connected to the connection point between the source of the fifth switch and the cathode of the second diode. The other end of the third inductor is connected to the connection point between the positive terminal of the third energy storage capacitor and the negative terminal of the first energy storage capacitor. The positive terminal of the third energy storage capacitor is connected to the source of the third switch in the switch module.

10. The pulsed sputtering power supply of claim 7, wherein, The state of the switch module includes at least one of the following states: a first state where the first switch is on and the second switch is on and the third switch is off; a second state where the first switch is off and the second switch is on and the third switch is off; a third state where the first switch is off and the second switch is off and the third switch is on; and a fourth state where the first switch is off and the second switch is off and the third switch is off. The pulsed sputtering power supply provides the second voltage to the outside in the first state, provides the first voltage to the outside in the second state, and provides the third voltage to the outside in the third state.

11. A semiconductor process apparatus, characterized by, A pulsed sputter power supply according to any one of claims 1-10 and a semiconductor process apparatus body.

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