Method for manufacturing semiconductor device and manufacturing apparatus for semiconductor device

Abstract

The present disclosure provides a method for manufacturing a semiconductor device and a manufacturing apparatus for a semiconductor device. The method for manufacturing the semiconductor device includes the following steps: disposing a workpiece to be etched on an electrostatic chuck located in an etching chamber, and etching the workpiece to be etched; during the process of etching the workpiece to be etched, applying at least one positive voltage and at least one negative voltage having a polarity opposite to that of the positive voltage to a stage in the electrostatic chuck. This manufacturing method can remove solid particles adhering to the surface of the workpiece to be etched, thereby improving the yield of the manufactured semiconductor device.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor technology, and particularly to a manufacturing method and a manufacturing apparatus for semiconductor devices. Background Art

[0002] During the production process of semiconductor devices, multiple etching processes are usually required. In the etching process, plasma or chemical reagents are used to etch the film structure on the surface of the workpiece, and solid particles including reaction products generated during the etching process are evacuated from the reaction chamber by a vacuum pump. However, in the actual preparation process, it is difficult for the vacuum pump to completely evacuate all solid particles, and there are often some solid particles adsorbed on the surface of the workpiece. This will affect the subsequent film deposition process, resulting in quality problems in the film layer and ultimately affecting the device yield. Summary of the Invention

[0003] Based on this, it is necessary to provide a manufacturing method for semiconductor devices in view of the problems in the above background art, which can remove the solid particles attached to the surface of the workpiece to be etched, thereby improving the yield of the manufactured semiconductor devices.

[0004] According to some embodiments of the present disclosure, a manufacturing method for semiconductor devices is provided, which includes the following steps:

[0005] Place the workpiece to be etched on an electrostatic chuck, and sequentially perform a first etching process, a transition process, and a second etching process on the workpiece to be etched;

[0006] During the transition process, perform one or more particle removal processes on the electrostatic chuck synchronously. The particle removal process includes applying a positive voltage and a negative voltage with a polarity opposite to that of the positive voltage to the electrostatic chuck once. During the particle removal process, adjust the voltage value of the positive voltage and the voltage value of the negative voltage according to the air pressure in the etching chamber.

[0007] In some embodiments of the present disclosure, during the transition process, the air pressure in the etching chamber gradually changes with time, and the voltage value of the positive voltage and the voltage value of the negative voltage gradually change with the change of the air pressure.

[0008] In some embodiments of the present disclosure, during the particle removal process, the voltage value of the positive voltage has a linear relationship with the air pressure in the etching chamber, and the voltage value of the negative voltage has a linear relationship with the air pressure in the etching chamber.

[0009] In some embodiments of the present disclosure, the voltage value of the forward voltage and the voltage value of the reverse voltage both satisfy the following relationship with the air pressure in the etching chamber: V = k×P + c, where V is the voltage value of the forward voltage or the voltage value of the reverse voltage, P is the air pressure in the etching chamber, and both k and c are constants.

[0010] In some embodiments of the present disclosure, during a single particle removal process, the voltage value of the forward voltage is equal to the voltage value of the reverse voltage.

[0011] In some embodiments of the present disclosure, during a single particle removal process, the duration of applying the forward voltage is equal to the duration of applying the reverse voltage.

[0012] In some embodiments of the present disclosure, the number of times of the particle removal process is multiple, and multiple particle removal processes are continuously performed during the transition process.

[0013] In some embodiments of the present disclosure, during multiple particle removal processes, the forward voltage and the reverse voltage are alternately applied.

[0014] In some embodiments of the present disclosure, a DC-DC converter is provided in the circuit structure coupled to the electrostatic chuck, and the DC-DC converter is used to change the polarity and voltage value of the voltage applied to the electrostatic chuck;

[0015] When applying a reverse voltage to the electrostatic chuck, the polarity of the voltage applied to the electrostatic chuck is changed by the DC-DC converter.

[0016] Furthermore, the present disclosure also provides a manufacturing apparatus for a semiconductor device, which includes an etching chamber, an electrostatic chuck, a circuit structure, and a vacuum pump;

[0017] The vacuum pump is used to extract the gas in the etching chamber;

[0018] The electrostatic chuck is disposed in the etching chamber, the electrostatic chuck is coupled to the circuit structure, a DC-DC converter is provided in the circuit structure, the DC-DC converter is used to change the polarity of the voltage applied to the electrostatic chuck, and the DC-DC converter is configured to adjust the voltage value of the applied voltage according to the air pressure in the etching chamber.

[0019] In at least one embodiment of the present disclosure, during the transition process, one or more particle removal processes are synchronously performed on the electrostatic chuck. The particle removal process includes applying a positive voltage and a negative voltage to the electrostatic chuck once each. The positive voltage is used to polarize the surface of the workpiece to be etched. Due to the principle of opposite charges attracting each other in Coulomb's law, the workpiece to be etched can be adsorbed on the electrostatic chuck. At this time, the polarity of the particle surface is opposite to that of the electrostatic chuck. The applied negative voltage is used to change the polarity of the electrostatic chuck. At this time, the polarity of the electrostatic chuck is the same as that of the particle, and the electrostatic chuck generates a repulsive force on the particle. This repulsive force can drive the particle away from the electrostatic chuck and is easily evacuated by the vacuum pump. Further, according to the air pressure in the etching chamber, the voltage value of the positive voltage and the voltage value of the negative voltage are adjusted so that the Coulomb force of the electrostatic chuck and the pumping speed of the vacuum pump are coordinated in the same frequency, and a relatively stable particle removal ability is maintained during the transition process, thereby further reducing the amount of particles adsorbed on the surface of the workpiece. Therefore, this manufacturing method can remove the solid particles attached to the surface of the workpiece to be etched, thereby improving the yield of the manufactured semiconductor device.

[0020] The above description is only an overview of the technical solution of the present invention. In order to be able to understand the technical means of the present invention more clearly and implement it according to the content of the specification, the following describes the preferred embodiments of the present invention in detail in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of the present disclosure. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained according to these drawings.

[0022] Figure 1 It is a schematic structural diagram of a manufacturing apparatus for a semiconductor device;

[0023] Figure 2 It is a schematic diagram of the change curve of the air pressure in the etching chamber with time during the transition process;

[0024] Figure 3 For Figure 2 It is a schematic diagram of the change curve of the voltage applied to the electrostatic chuck corresponding thereto.

[0025] Among them, the meanings of the reference numerals are as follows:

[0026] 110, stage; 120, electrostatic chuck; 130, DC-DC converter; 210, etching chamber; 220, workpiece to be etched; 230, vacuum pump; 240, air duct. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0027] To facilitate understanding of this text, a more comprehensive description of this text will be given below. Preferred embodiments of this text are presented herein. However, this text can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided to make the content of this text more thorough and comprehensive.

[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the technical field to which this text belongs. The terms used herein in the specification of this text are only for the purpose of describing specific embodiments and are not intended to limit this text.

[0029] It should be understood that when an element or layer is referred to as "on", "adjacent to", "connected to" or "coupled to" another element or layer, it can be directly on, adjacent to, connected or coupled to the other element or layer, or there may also be intervening elements or layers. In contrast, when an element is referred to as "directly on", "directly adjacent to", "directly connected to" or "directly coupled to" another element or layer, there are no intervening elements or layers. It should be understood that although the terms first, second, third, etc. may be used to describe various elements, components, regions, layers and / or parts, these elements, components, regions, layers and / or parts should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or part from another element, component, region, layer or part.

[0030] Spatial relationship terms such as "under", "below", "lower", "beneath", "above", "upper", etc. are used herein for convenience in describing the relationship of one element or feature to another element or feature. It should be understood that the spatial relationship terms are also intended to include different orientations of the device in use and operation. For example, if the device in the figures is flipped, then an element or feature described as "under" or "beneath" or "below" another element or feature will be oriented "on" the other element or feature. Thus, the exemplary terms "under" and "below" can include both an upper and a lower orientation. The device may be otherwise oriented (e.g., rotated 90 degrees or other orientations) and the spatial descriptors used will be interpreted accordingly.

[0031] The purpose of the terms used herein is only to describe specific embodiments and is not a limitation of the present disclosure. As used herein, the singular forms "a", "an" and "the" are also intended to include the plural forms unless the context clearly dictates otherwise. It should also be understood that the terms "comprising" and / or "including", when used in this specification, specify the presence of features, integers, steps, operations, elements and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or groups. As used herein, the term "and / or" includes any and all combinations of the related listed items.

[0032] An electrostatic chuck refers to a device that fixes and supports a workpiece to be etched through the principle of electrostatic adsorption. When in use, a power supply applies a voltage to the electrostatic chuck to generate an electrostatic field. This electrostatic field causes induced charges with opposite polarities to be generated on the surface of the workpiece to be etched. Due to the attraction between opposite charges, the workpiece to be etched can be stably adsorbed and fixed on the electrostatic chuck. In traditional etching processes, the voltage polarity applied to the electrostatic chuck is usually constant to ensure the stability of the workpiece to be etched. During the research process of the present disclosure, it was found that plasma is usually required for etching during the etching process. In the actual etching process, tiny particles in the etching chamber are charged under the influence of the radio frequency power supply, so the particles can be suspended in the plasma during the etching process. However, there is a transition process at the end of one etching stage and before the start of the next etching stage. At this time, the air pressure in the etching chamber changes, the radio frequency power supply stops working, and the particles fall onto the workpiece to be etched under the influence of gravity and are polarized and attracted by the electrostatic chuck. It is difficult for the fallen particles to be resuspended in the plasma from the workpiece to be etched.

[0033] The present disclosure provides a method for manufacturing a semiconductor device that can reduce the particles attached to the workpiece to be etched, which includes the following steps: setting the workpiece to be etched on the electrostatic chuck, sequentially performing a first etching process, a transition process, and a second etching process on the workpiece to be etched; synchronously performing one or more particle removal processes on the electrostatic chuck during the transition process, the particle removal process includes applying a positive voltage and a negative voltage with a polarity opposite to that of the positive voltage to the electrostatic chuck once, and during the particle removal process, adjusting the voltage value of the positive voltage and the voltage value of the negative voltage according to the air pressure in the etching chamber.

[0034] It can be understood that the positive voltage applied to the electrostatic chuck in this embodiment is used to make the workpiece to be etched adsorbed on the electrostatic chuck, while the negative voltage has a polarity opposite to that of the positive voltage. The naming of the "positive voltage" and "negative voltage" in this embodiment is mainly used to distinguish the two in terms of polarity, rather than to limit the current direction applied by the power supply or the specific polarity of the electrostatic chuck.

[0035] In this embodiment, during the transition process, one or more particle removal processes are synchronously performed on the electrostatic chuck. The particle removal process includes applying a positive voltage and a negative voltage to the electrostatic chuck once. The positive voltage is used to polarize the surface of the workpiece to be etched. Due to the principle of attraction between opposite charges in Coulomb's law, the workpiece to be etched can be adsorbed on the electrostatic chuck. At this time, the polarity of the particle surface is opposite to that of the electrostatic chuck. The applied negative voltage is used to change the polarity of the electrostatic chuck. At this time, the polarity of the electrostatic chuck is the same as that of the particle, and the electrostatic chuck generates a repulsive force on the particle. This repulsive force can drive the particle away from the electrostatic chuck and is easily pumped away by the vacuum pump. Further, according to the air pressure in the etching chamber, the voltage value of the positive voltage and the voltage value of the negative voltage are adjusted, so that the Coulomb force of the electrostatic chuck and the pumping speed of the vacuum pump are coordinated in the same frequency, and a relatively stable particle removal ability is maintained during the transition process, thereby further reducing the amount of particles adsorbed on the surface of the workpiece. Therefore, this manufacturing method can remove the solid particles attached to the surface of the workpiece to be etched, thereby improving the yield of the manufactured semiconductor device.

[0036] The present disclosure also provides a manufacturing apparatus for a semiconductor device for implementing this manufacturing method. For ease of understanding, the structure of the manufacturing apparatus for the semiconductor device will be described first below. Figure 1 It is a schematic structural diagram of a manufacturing apparatus for a semiconductor device. Refer to Figure 1 As shown, the manufacturing apparatus for the semiconductor device includes an etching chamber 210, an electrostatic chuck 120, a circuit structure, and a vacuum pump 230. Among them, the vacuum pump 230 is used to extract the gas in the etching chamber 210. The electrostatic chuck 120 is disposed in the etching chamber 210, and the electrostatic chuck 120 is coupled to the circuit structure. The circuit structure is used to apply a voltage to the electrostatic chuck 120 so that the electrostatic chuck 120 has a specific polarity.

[0037] Refer to Figure 1 As shown, as some examples of this embodiment, the vacuum pump 230 can be connected to the inside of the etching chamber 210 through a gas pipe 240, and the vacuum pump 230 can extract the gas in the etching chamber 210 through the gas pipe 240.

[0038] Refer to Figure 1As shown, in this embodiment, the electrostatic chuck 120 is used to hold the workpiece 220 to be etched located in the etching chamber 210. The stage 110 is disposed on one side of the electrostatic chuck 120. Specifically, the electrostatic chuck 120 has a bearing surface for holding the workpiece 220 to be etched and a back surface opposite to the bearing surface, and the stage 110 can be disposed on the side of the back surface of the electrostatic chuck 120 away from the bearing surface. The stage 110 is electrically connected to a circuit structure, and a DC-DC converter 130 is provided in the circuit structure. The DC-DC converter 130 is used to change the polarity of the voltage applied to the electrostatic chuck 120, and the DC-DC converter 130 is configured to regulate the voltage value of the applied voltage according to the air pressure in the etching chamber 210. It can be understood that this circuit structure can be electrically connected to an external power source. A control module (not shown in the figure) can be provided, and this control module is used to regulate the voltage value of the applied voltage according to the air pressure in the etching chamber 210. The control module can include a programmable logic controller and a processor with a built-in program to regulate the voltage value of the voltage applied by the DC-DC converter 130. The control module can also include other devices, such as a pressure sensor for measuring the air pressure in the etching chamber 210.

[0039] In the embodiment of the present disclosure, by providing the DC-DC converter 130, the polarity of the voltage applied to the electrostatic chuck 120 can be changed during use, and both a positive voltage and a negative voltage opposite to the polarity of the positive voltage can be applied to the electrostatic chuck 120. Therefore, the manufacturing apparatus of the semiconductor device can be used to implement the manufacturing method of the semiconductor device of the present disclosure.

[0040] The manufacturing method of the semiconductor device according to the embodiment of the present disclosure includes a process of etching the workpiece 220 to be etched. As some examples of this embodiment, the manufacturing method of the semiconductor device is carried out using the manufacturing apparatus in the above embodiment. In the manufacturing method of an embodiment, the manufacturing method includes the following steps: setting the workpiece 220 to be etched on the electrostatic chuck 120, and sequentially performing a first etching process, a transition process, and a second etching process on the workpiece to be etched; during the transition process, performing one or more particle removal processes on the electrostatic chuck synchronously. The particle removal process includes applying a positive voltage and a negative voltage opposite to the polarity of the positive voltage to the electrostatic chuck 120 once. During the particle removal process, the voltage values of the positive voltage and the negative voltage are regulated according to the air pressure in the etching chamber 210.

[0041] As some examples of this embodiment, the workpiece 220 to be etched may include a wafer and an etching film layer located on the wafer. The material of the etching film layer may include at least one of silicon nitride, silicon oxide, and titanium nitride. The material of the etching film layer may not be limited to this, for example, it may also include photoresist material, hard mask material, etc.

[0042] As some examples of this embodiment, the film layer to be etched has one or more layers. The first etching process and the second etching process may be two successive etchings on the same layer of the film layer to be etched, or may be two successive etchings on two layers of the film layer to be etched. In this embodiment, there are two layers of the film layer to be etched, namely a silicon nitride layer and a silicon oxide layer. The first etching process is for etching the silicon nitride layer, and the second etching process is for etching the silicon oxide layer.

[0043] As some examples of this embodiment, in this preparation method, the etching methods in the first etching process and the second etching process may be dry etching, that is, using plasma to etch the workpiece 220 to be etched.

[0044] As some examples of this embodiment, during the process of performing the first etching process, the transition process, and the second etching process on the workpiece 220 to be etched, a vacuum pump 230 may be used to evacuate the etching chamber 210 to maintain or change the air pressure in the etching chamber 210.

[0045] In this example, during the process of performing the first etching process, the transition process, and the second etching process on the workpiece 220 to be etched, the air pressure in the etching chamber 210 may be controlled to be 150 Pa to 2000 Pa. It can be understood that during different etching stages or when etching different materials, the air pressure in the etching chamber 210 can be adjusted correspondingly according to specific requirements.

[0046] In this embodiment, during the transition process between the first etching process and the second etching process, the air pressure in the etching chamber 210 gradually changes with time. As some examples of this embodiment, the air pressure required in the etching chamber 210 in the first etching process is different from the air pressure required in the etching chamber 210 in the second etching process. During the transition process, the air pressure in the etching chamber 210 gradually adjusts from the air pressure required in the first etching process to the air pressure required in the second etching process.

[0047] As some examples of this embodiment, the voltage value of the forward voltage and the voltage value of the reverse voltage gradually change with the change of the air pressure. The purpose is to avoid the dropping of particles during the transition process and enable the particles to be evacuated by the vacuum pump in a timely manner.

[0048] As some examples of this embodiment, the step of regulating the voltage value of the forward voltage and the voltage value of the reverse voltage according to the air pressure in the etching chamber 210 includes: when the air pressure value in the etching chamber 210 is relatively large, controlling the voltage value of the forward voltage and the voltage value of the reverse voltage in the particle removal process to be relatively large; when the air pressure value in the etching chamber 210 is relatively small, controlling the voltage value of the forward voltage and the voltage value of the reverse voltage in the particle removal process to be relatively small.

[0049] In this example, when the air pressure in the etching chamber 210 is relatively low, the pumping rate of the vacuum pump 230 is relatively fast. At this time, a relatively small voltage value is applied to the electrostatic chuck 120 to reduce the Coulomb force of the particles on the surface of the electrostatic chuck 120, which is more conducive to the full removal of the particles. When the air pressure in the etching chamber 210 is relatively high, the pumping rate of the vacuum pump 230 is relatively slow. At this time, a relatively large voltage value is applied to the electrostatic chuck 120 to increase the Coulomb force of the particles on the surface of the electrostatic chuck 120, which is more conducive to the full removal of the particles. By regulating the voltage value in this way, it is beneficial to further improve the particle removal ability in the transition process.

[0050] As some examples of this embodiment, during the particle removal process, the voltage value of the forward voltage has a linear relationship with the air pressure in the etching chamber 210, and the voltage value of the reverse voltage has a linear relationship with the air pressure in the etching chamber 210. Setting the applied voltage value to have a linear relationship with the air pressure in the etching chamber 210 can make the particle removal ability more stable throughout the etching process.

[0051] As some examples of this embodiment, the voltage value of the forward voltage and the voltage value of the reverse voltage both satisfy the following relationship with the air pressure in the etching chamber: V = k×P + c, where V is the voltage value of the forward voltage or the voltage value of the reverse voltage, P is the air pressure in the etching chamber, and k and c are both constants.

[0052] In the actual transition process, the air pressure in the etching chamber 210 can change intermittently or be approximately considered to change intermittently. Among them, intermittent change means that the air pressure in the etching chamber 210 remains constant or is approximately considered to remain constant within a relatively short time period (for example, within 1 s), and the air pressure jumps between adjacent time periods. At this time, the particle removal process can be carried out synchronously corresponding to this time period, that is, a particle removal process is carried out for each time period, and the electrostatic chuck 120 is subjected to multiple particle removal processes during the entire transition process.

[0053] It can be understood that during each particle removal process, applying a forward voltage is beneficial to ensuring that the workpiece to be etched 220 is stably set on the electrostatic chuck 120, and applying a reverse voltage can generate a repulsive force on the particles attached to the electrostatic chuck 120, so as to facilitate the detachment of the particles from the surface of the workpiece to be etched 220 and be pumped away by the vacuum pump 230.

[0054] It can be understood that in this embodiment, when changing the applied voltage, the polarity and / or magnitude of the voltage can be adjusted. This adjustment can be completed instantaneously, that is, after applying a forward voltage or a reverse voltage, the polarity can be instantaneously adjusted and / or a reverse voltage or a forward voltage can be immediately applied.

[0055] As some examples of this embodiment, applying a reverse voltage to the stage 110 is performed immediately after applying a forward voltage. Here, "immediately after applying a forward voltage" means that there is no interruption between applying the forward voltage and applying the reverse voltage. For example, the forward voltage applied to the stage 110 can be ended instantaneously, and at the same time, the reverse voltage is started to be applied to the stage 110.

[0056] In the circuit structure of a conventional electrostatic chuck 120, only a forward voltage can be applied to the electrostatic chuck 120. Corresponding to the change in the voltage application method, as some examples of this embodiment, a DC-DC converter 130 is provided in the circuit structure of the electrostatic chuck 120. The DC-DC converter 130 is used to change the polarity and voltage value of the voltage applied to the stage 110. When applying a reverse voltage to the stage 110 in this embodiment, the DC-DC converter 130 changes the polarity of the voltage applied to the stage 110. The DC-DC converter 130 can adjust the forward voltage applied by the original circuit structure to be changed into a reverse voltage, so as to instantaneously complete the change of the applied voltage polarity. By providing the DC-DC converter 130, the manufacturing method of this semiconductor device can be realized without significantly modifying the existing equipment.

[0057] In this embodiment, during a single particle removal process, the voltage value applied each time can be kept fixed, that is, the voltage value of the forward voltage applied each time remains constant, and the voltage value of the reverse voltage applied each time also remains constant. Or, in other embodiments, during a single particle removal process, the voltage value of the forward voltage or the reverse voltage applied each time can also vary.

[0058] As some examples of this embodiment, during a single particle removal process, the voltage value of the forward voltage applied is equal to the voltage value of the reverse voltage applied. Controlling the voltage values of the forward voltage and the reverse voltage to be equal is beneficial to ensuring that particles of different charging types can be removed more fully.

[0059] As some examples of this embodiment, during a single particle removal process, the duration of applying the forward voltage is equal to the duration of applying the reverse voltage. Controlling the duration of applying the forward voltage and the duration of applying the reverse voltage to be equal is beneficial to ensuring that particles of different charging types can be removed more fully.

[0060] As some examples of this embodiment, the number of particle removal processes is multiple, and multiple particle removal processes are continuously performed during the transition process.

[0061] As some examples of this embodiment, during the transition process, a positive voltage and a negative voltage can be alternately applied to the stage 110. For example, after each application of the positive voltage, a negative voltage is applied once, and then the next positive voltage is applied, and so on. Alternately applying a positive voltage and a negative voltage to the stage 110 is beneficial to improving the removal probability of the adsorbed particles on the workpiece 220 to be etched while ensuring the stable setting of the workpiece 220 to be etched, and improving the yield of the manufactured semiconductor device.

[0062] The present disclosure also provides a specific implementation manner of the above embodiment to specifically illustrate the manner of setting the applied voltage value according to the air pressure in the etching chamber 210.

[0063] As some examples of this embodiment, the voltage value of the negative voltage applied to the stage 110 is 300V to 1000V. The voltage value refers to the absolute value of the voltage, that is, the voltage value regardless of the current direction. Controlling the voltage value of the negative voltage to be 300V to 1000V can generate a relatively appropriate repulsive force, effectively removing the particles while ensuring the stable placement of the workpiece 220 to be etched.

[0064] Further, in this example, the voltage value of the negative voltage applied to the stage 110 can be 300V, 400V, 500V, 600V, 700V, 800V, 900V, 1000V, or the voltage value of the negative voltage can also be in the range between any two of the above voltage values.

[0065] Figure 2 It is a schematic diagram of the change curve of air pressure with time during the transition process in a manufacturing method of a semiconductor device, where the abscissa represents time and the ordinate represents the air pressure in the etching chamber 210. Referring to Figure 2 As shown, the first particle removal process is performed between the time t0 and the time t1, and the air pressure in the etching chamber 210 during the first particle removal process can be considered as P1. Then, the second particle removal process is performed between the time t1 and the time t2, and the air pressure in the etching chamber 210 during the second particle removal process can be considered as P2. Then, the third particle removal process is performed between the time t2 and the time t3, and the air pressure in the etching chamber 210 during the third particle removal process can be considered as P3. Then, the fourth particle removal process is performed between the time t3 and the time t4, and the air pressure in the etching chamber 210 during the fourth particle removal process can be considered as P4. Then, the fifth particle removal process is performed between the time t4 and the time t5, and the air pressure in the etching chamber 210 during the fifth particle removal process can be considered as P5. Then, the sixth particle removal process is performed between the time t5 and the time t6, and the air pressure in the etching chamber 210 during the sixth particle removal process can be considered as P6.

[0066] In the content shown as Figure 2 below, during the first to fifth particle removal processes, the air pressure in the etching chamber 210 gradually decreases, i.e., P1 > P2 > P3 > P4 > P5. During the fifth to sixth particle removal processes, the air pressure in the etching chamber 210 rises, i.e., P5 < P6.

[0067] Figure 3 For Figure 2 the schematic diagram of the voltage curve change applied to the stage 110 corresponding thereto. Referring to Figure 3 the figure below, during the first particle removal process, a positive voltage with a value of V1 is applied to the stage 110 starting from time t0 until the middle time of the first particle removal process, that is, (t1 - t0) / 2 time, and then the polarity of the voltage is changed, and a negative voltage with a value of V1 is applied to the stage 110 until the end of the first particle removal process. During the second particle removal process, a positive voltage with a value of V2 is applied to the stage 110 starting from time t1 until the middle time of the second particle removal process, and then the polarity of the voltage is changed, and a negative voltage with a value of V2 is applied to the stage 110 until the end of the second particle removal process. And so on. During the sixth particle removal process, a positive voltage with a value of V6 is applied to the stage 110 starting from time t5 until the middle time of the sixth particle removal process, and then the polarity of the voltage is changed, and a negative voltage with a value of V6 is applied to the stage 110 until the end of the sixth particle removal process. It can be understood that in Figure 3 the figure, V1 represents the application of a positive voltage with a value of V1, and -V1 represents the application of a negative voltage with a value of V1.

[0068] Referring to Figure 3As shown, during the first particle removal process, i.e., in the time period from t0 to t1, a positive voltage is applied in the first half of the time. At this time, the workpiece 220 to be etched is adsorbed on the electrostatic chuck 120, and the particles on the surface of the workpiece 220 to be etched are also adsorbed together. Assuming that the surface of the stage 110 close to the workpiece 220 to be etched is positively charged at this time, the surface of the particles is negatively charged. Then, a reverse voltage is applied to the stage 110 in the second half of the time. At this time, the surface of the stage 110 close to the workpiece 220 to be etched is negatively charged, which can generate an instantaneous repulsive force on the particles with negatively charged surfaces, causing the particles to move away from the workpiece 220 to be etched. At this time, the particles can be evacuated along with the gas flow in the etching chamber 210. At the same time as the start of the second particle removal process, a positive voltage and a reverse voltage are applied to the stage 110 and the voltage value is adjusted according to the change in air pressure, which can make the particle removal ability in adjacent two particle removal processes relatively stable, so as to fully remove the particles on the surface of the second workpiece 220 to be etched. By analogy, by applying a positive voltage and a reverse voltage during each particle removal process, the particles dropped between the etching stages can be removed more effectively.

[0069] Further, referring to Figure 3 as shown, corresponding to the change rule of the air pressure value in Figure 2 , during the process from the first particle removal process to the fifth particle removal process, the voltage values of the positive voltage and the reverse voltage applied to the stage 110 both gradually decrease, that is, V1 > V2 > V3 > V4 > V5. During the process from the fifth particle removal process to the sixth particle removal process, the voltage values of the positive voltage and the reverse voltage applied to the stage 110 increase, that is, V5 < V6. That is, during the particle removal process with a larger air pressure, the voltage value applied to the stage 110 is also larger. This is beneficial to maintaining a relatively stable particle removal ability throughout the transition process.

[0070] In this embodiment, during the actual etching process, the program of the DC-DC converter 130 can be set correspondingly according to the program of the change of the air pressure in the etching chamber 210 over time, so that the voltage applied to the stage 110 changes according to the air pressure.

[0071] Please note that the above embodiments are for illustrative purposes only and do not imply any limitation to this article.

[0072] It should be understood that, unless otherwise explicitly stated herein, there is no strict order restriction for the execution of the steps, and these steps can be executed in other orders. Moreover, at least some of the steps in the preparation process may include multiple sub-steps or multiple stages, and these sub-steps or stages do not necessarily need to be completed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed alternately or in turn with at least some of the other steps or the sub-steps or stages of the other steps.

[0073] Each embodiment in this specification is described in a progressive manner. Each embodiment focuses on the differences from other embodiments. For the same or similar parts among the embodiments, reference can be made to each other.

[0074] The technical features of the above embodiments can be combined arbitrarily. For the sake of concise description, 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, it should be considered as the scope recorded in this specification.

Claims

1. A method for manufacturing a semiconductor device, characterized in that, The method includes the following steps: Place the workpiece to be etched on an electrostatic chuck, and successively perform a first etching process, a transition process, and a second etching process on the workpiece to be etched; During the transition process, perform one or more particle removal processes on the electrostatic chuck synchronously. The particle removal process includes applying a positive voltage and a negative voltage with a polarity opposite to that of the positive voltage to the electrostatic chuck. During the particle removal process, adjust the voltage values of the positive voltage and the negative voltage according to the air pressure in the etching chamber. During the transition process, the air pressure in the etching chamber gradually changes with time, and the voltage values of the positive voltage and the negative voltage gradually change with the change of the air pressure. When the air pressure value in the etching chamber is large, control the voltage values of the positive voltage and the negative voltage to be large. When the air pressure value in the etching chamber is small, control the voltage values of the positive voltage and the negative voltage to be small.

2. The manufacturing method of the semiconductor device according to claim 1, characterized in that, During the particle removal process, the voltage value of the positive voltage has a linear relationship with the air pressure in the etching chamber, and the voltage value of the negative voltage has a linear relationship with the air pressure in the etching chamber.

3. The manufacturing method of the semiconductor device according to claim 2, characterized in that, The voltage values of the positive voltage and the negative voltage both satisfy the following relationship with the air pressure in the etching chamber: V = k×P + c, where V is the voltage value of the positive voltage or the negative voltage, P is the air pressure in the etching chamber, and k and c are both constants.

4. The manufacturing method of the semiconductor device according to any one of claims 1 to 3, characterized in that, During a single particle removal process, the voltage value of the positive voltage is equal to the voltage value of the negative voltage.

5. The manufacturing method of the semiconductor device according to any one of claims 1 to 3, characterized in that, During a single particle removal process, the duration of applying the positive voltage is equal to the duration of applying the negative voltage.

6. The manufacturing method of the semiconductor device according to any one of claims 1 to 3, characterized in that, The number of particle removal processes is multiple, and multiple particle removal processes are continuously performed during the transition process.

7. The manufacturing method of the semiconductor device according to claim 6, characterized in that, During multiple particle removal processes, the positive voltage and the negative voltage are alternately applied.

8. The manufacturing method of the semiconductor device according to any one of claims 1 to 3, characterized in that, A DC-DC converter is provided in the circuit structure coupled to the electrostatic chuck. The DC-DC converter is used to change the polarity and voltage value of the voltage applied to the electrostatic chuck; When applying a negative voltage to the electrostatic chuck, change the polarity of the voltage applied to the electrostatic chuck through the DC-DC converter.

9. A manufacturing apparatus for a semiconductor device, characterized in that, It includes an etching chamber, an electrostatic chuck, a circuit structure, and a vacuum pump; The vacuum pump is used to extract the gas in the etching chamber; The electrostatic chuck is disposed in the etching chamber. The electrostatic chuck is coupled to the circuit structure. A DC-DC converter is provided in the circuit structure. The DC-DC converter is used to change the polarity of the voltage applied to the electrostatic chuck, and the DC-DC converter is configured to adjust the voltage value of the applied voltage according to the air pressure in the etching chamber. When the air pressure value in the etching chamber is large, control the voltage value of the applied voltage to be large. When the air pressure value in the etching chamber is small, control the voltage value of the applied voltage to be small.

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