Semiconductor device manufacturing method and semiconductor device manufacturing apparatus

Abstract

The invention provides a manufacturing method of a semiconductor device and a manufacturing apparatus of the semiconductor device. The manufacturing method of the semiconductor device comprises the following steps that a workpiece to be etched is arranged on an electrostatic chuck located in an etching cavity, and the workpiece to be etched is etched; and in the process of etching the workpiece to be etched, applying at least one forward voltage and at least one backward voltage with the polarity opposite to that of the forward voltage to a carrying table in the electrostatic chuck. According to the preparation method, the solid particles attached to the surface of the workpiece to be etched can be removed, so that the yield of the prepared semiconductor device is improved.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor technology, and in particular to a method for manufacturing a semiconductor device and a device for manufacturing a semiconductor device. Background Art

[0002] The production process of semiconductor devices usually requires multiple etching processes. In the etching process, plasma or chemical reagents are used to etch the film structure on the surface of the workpiece. Solid particles including reaction products generated during the etching process are pumped out of the reaction chamber by a vacuum pump. However, in the actual preparation process, it is difficult for the vacuum pump to completely extract all solid particles, and some solid particles often remain adsorbed on the surface of the workpiece. This will affect the deposition process of the subsequent film layer, 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 method for manufacturing a semiconductor device to address the problems in the above-mentioned background technology. The method can remove solid particles attached to the surface of the workpiece to be etched, thereby improving the yield of the prepared semiconductor device.

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

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

[0006] During the transition process, the electrostatic chuck is synchronously subjected to one or more particle removal processes, wherein the particle removal process includes applying a forward voltage and a reverse voltage with a polarity opposite to the forward voltage to the electrostatic chuck, and during the particle removal process, the voltage value of the forward voltage and the voltage value of the reverse voltage are regulated according to the gas pressure in the etching chamber.

[0007] In some embodiments of the present disclosure, in the transition process, the gas pressure in the etching chamber gradually changes with time, and the voltage value of the forward voltage and the voltage value of the reverse voltage gradually change with the change of the gas pressure.

[0008] In some embodiments of the present disclosure, during the particle removal process, the voltage value of the forward voltage is linearly related to the gas pressure in the etching chamber, and the voltage value of the reverse voltage is linearly related to the gas 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 satisfy the following relationship with the gas 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 gas pressure in the etching chamber, and k and c are both 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 particle removal process is performed multiple times, and the multiple particle removal processes are performed continuously during the transition process.

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

[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 convert the polarity and voltage value of the voltage applied to the electrostatic chuck;

[0015] When a reverse voltage is applied 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 semiconductor device manufacturing apparatus, 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 disposed 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 gas pressure in the etching chamber.

[0019] In at least one embodiment of the present disclosure, the electrostatic chuck is synchronously subjected to one or more particle removal processes in the transition process, and the particle removal process includes applying a forward voltage and a reverse voltage to the electrostatic chuck. The forward voltage is used to polarize the surface of the workpiece to be etched. Due to the principle of opposites attracting in Coulomb's law, the workpiece to be etched can be adsorbed on the electrostatic chuck, and the polarity of the particle surface is opposite to that of the electrostatic chuck. The applied reverse voltage is used to change the polarity of the electrostatic chuck. At this time, the polarity of the electrostatic chuck is the same as the polarity of the particle, and the electrostatic chuck generates a repulsive force on the particle. The repulsive force can drive the particle away from the electrostatic chuck and is easily extracted by the vacuum pump. Further, the voltage value of the forward voltage and the voltage value of the reverse voltage are regulated according to the air pressure in the etching chamber, so that the Coulomb force of the electrostatic chuck and the suction speed of the vacuum pump are coordinated at the same frequency, and a relatively stable particle removal capability is maintained in the transition process, thereby further reducing the amount of particles adsorbed on the surface of the workpiece. Therefore, the preparation method can remove solid particles attached to the surface of the workpiece to be etched, thereby improving the yield of the prepared semiconductor device.

[0020] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention and implement it according to the contents of the specification, the following is a detailed description of the preferred embodiments of the present invention 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 drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present disclosure. For ordinary technicians in this field, drawings of other embodiments can be obtained based on these drawings without creative work.

[0022] Figure 1 The present invention is a schematic structural diagram of a semiconductor device manufacturing device;

[0023] Figure 2 A schematic diagram of a curve showing changes in the gas pressure of the etching chamber over time during the transition process;

[0024] Figure 3 For Figure 2 The corresponding schematic diagram of the voltage curve applied to the electrostatic chuck.

[0025] The reference numerals and their meanings are as follows:

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

[0027] To facilitate understanding of the present invention, a more comprehensive description of the present invention is provided below. The preferred embodiments of the present invention are given herein. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the content of the present invention more thorough and comprehensive.

[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this document pertains. The terms used herein in the specification of this document are only for describing specific embodiments and are not intended to limit this document.

[0029] It should be understood that when an element or layer is referred to as being "on, "adjacent to, "connected to, or "coupled to" another element or layer, it may be directly on, adjacent to, connected to, or coupled to the other element or layer, or there may be intervening elements or layers. In contrast, when an element is referred to as being "directly on, "directly adjacent to, "directly connected to, or "directly coupled to" another element or layer, there may be 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 portions, these elements, components, regions, layers, and / or portions should not be limited by these terms. These terms are merely used to distinguish one element, component, region, layer, or portion from another element, component, region, layer, or portion.

[0030] Spatially relative terms such as "under," "beneath," "below," "under," "above," "above," and the like may be used herein for ease of description to describe the relationship of one element or feature to other elements or features. It should be understood that the spatially relative terms are intended to also include different orientations of the device in use and operation. For example, if the device in the accompanying drawings is flipped, then the elements or features described as "under other elements" or "under" or "under" will be oriented as "over" the other elements or features. Thus, the exemplary terms "under" and "under" may include both upper and lower orientations. The device may be otherwise oriented (e.g., rotated 90 degrees or other orientations) and the spatial descriptors used may be interpreted accordingly.

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

[0032] An electrostatic chuck refers to a device that fixes and supports the workpiece to be etched by the principle of electrostatic adsorption. When in use, the power supply applies voltage to the electrostatic chuck to generate an electrostatic field. The electrostatic field causes the surface of the workpiece to be etched to generate induced charges of opposite polarity. Since the opposite charges attract each other, the workpiece to be etched can be stably adsorbed and fixed on the electrostatic chuck. In the traditional etching process, the polarity of the voltage applied to the electrostatic chuck is usually constant to ensure the stability of the workpiece to be etched. In 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, the tiny particles in the etching chamber are charged by 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 between the end of one etching stage and the beginning 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 to the workpiece to be etched under the influence of gravity and are polarized and attracted by the electrostatic chuck. It is difficult for the particles that fall to be resuspended in the plasma from the workpiece to be etched.

[0033] The present disclosure provides a method for manufacturing a semiconductor device capable of reducing particles attached to a workpiece to be etched, comprising the following steps: placing the workpiece to be etched on an electrostatic chuck, and sequentially performing a first etching process, a transition process, and a second etching process on the workpiece to be etched; while performing the transition process, synchronously performing one or more particle removal processes on the electrostatic chuck, the particle removal process comprising applying a forward voltage and a reverse voltage with a polarity opposite to the forward voltage to the electrostatic chuck, and during the particle removal process, regulating the voltage value of the forward voltage and the voltage value of the reverse voltage according to the gas pressure in the etching chamber.

[0034] It can be understood that the forward voltage applied to the electrostatic chuck in this embodiment is used to make the workpiece to be etched adsorbed on the electrostatic chuck, and the reverse voltage is opposite to the polarity of the forward voltage. The names of "forward voltage" and "reverse voltage" in this embodiment are mainly used to distinguish the two in terms of polarity, and are not used to limit the current direction applied by the power supply or the specific polarity of the electrostatic chuck.

[0035] In this embodiment, the electrostatic chuck is synchronously subjected to one or more particle removal processes in the transition process, and the particle removal process includes applying a forward voltage and a reverse voltage to the electrostatic chuck. The forward voltage is used to polarize the surface of the workpiece to be etched. Due to the principle of opposites attracting in Coulomb's law, the workpiece to be etched can be adsorbed on the electrostatic chuck, and the polarity of the particle surface is opposite to that of the electrostatic chuck. The applied reverse voltage is used to change the polarity of the electrostatic chuck. At this time, the polarity of the electrostatic chuck is the same as the polarity of the particle, and the electrostatic chuck generates a repulsive force on the particle. The repulsive force can drive the particle away from the electrostatic chuck and is easily extracted by the vacuum pump. Further, the voltage value of the forward voltage and the voltage value of the reverse voltage are regulated according to the air pressure in the etching chamber, so that the Coulomb force of the electrostatic chuck and the suction speed of the vacuum pump are coordinated at the same frequency, and a relatively stable particle removal capability is maintained in the transition process, thereby further reducing the amount of particles adsorbed on the surface of the workpiece. Therefore, the preparation method can remove solid particles attached to the surface of the workpiece to be etched, thereby improving the yield of the prepared semiconductor device.

[0036] The present disclosure also provides a semiconductor device manufacturing apparatus for implementing the manufacturing method. For ease of understanding, the structure of the semiconductor device manufacturing apparatus is first described below. Figure 1 The structure diagram of a semiconductor device manufacturing device is shown in FIG. Figure 1 As shown, the manufacturing apparatus of the semiconductor device includes an etching chamber 210, an electrostatic chuck 120, a circuit structure and a vacuum pump 230. 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] Reference Figure 1 As shown, as some examples of this embodiment, the vacuum pump 230 can be connected to the cavity of the etching chamber 210 through the gas pipe 240, and the vacuum pump 230 can extract the gas in the etching chamber 210 through the gas pipe 240.

[0038] Reference Figure 1As shown, in this embodiment, the electrostatic chuck 120 is used to carry the workpiece 220 to be etched in the etching chamber 210. The carrier 110 is arranged on one side of the electrostatic chuck 120. Specifically, the electrostatic chuck 120 has a carrying surface for carrying the workpiece 220 to be etched and a back surface opposite to the carrying surface, and the carrier 110 can be arranged on the back side of the electrostatic chuck 120 away from the carrying surface. The carrier 110 is electrically connected to the circuit structure, and a DC-DC converter 130 is arranged 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 adjust the voltage value of the applied voltage according to the gas pressure in the etching chamber 210. It can be understood that the circuit structure can be electrically connected to an external power supply. A control module (not shown in the figure) can be provided, and the control module is used to adjust the voltage value of the applied voltage according to the gas pressure in the etching chamber 210. The control module may include a programmable logic controller and a processor with a built-in program to control the voltage value applied by the DC-DC converter 130. The control module may 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, so that both a forward voltage and a reverse 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 of 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 performed using the manufacturing device as in the above embodiment. In the manufacturing method of one embodiment, the manufacturing method includes the following steps: placing 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; in the process of performing the transition process, the electrostatic chuck is synchronously subjected to one or more particle removal processes, and the particle removal process includes applying a forward voltage and a reverse voltage with a polarity opposite to the forward voltage to the electrostatic chuck 120. During the particle removal process, the voltage value of the forward voltage and the voltage value of the reverse voltage are regulated according to the gas pressure in the etching chamber 210.

[0041] As some examples of this embodiment, the workpiece 220 to be etched may include a wafer and a film layer to be etched on the wafer. The material of the film layer to be etched may include at least one of silicon nitride, silicon oxide and titanium nitride. The material of the film layer to be etched may also be not limited thereto, for example, it may also include a photoresist material, a 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 can be two etchings performed successively on the same film layer to be etched, or can be two etchings performed successively on two film layers to be etched. In this embodiment, the film layer to be etched has two layers, namely a silicon nitride layer and a silicon oxide layer. The first etching process etches the silicon nitride layer, and the second etching process etches the silicon oxide layer.

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

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

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

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

[0047] As some examples of this embodiment, the voltage values ​​of the forward voltage and the reverse voltage gradually change with the change of gas pressure, the purpose of which is to avoid the falling of particles during the transition process and enable the particles to be extracted by the vacuum pump in time.

[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 gas pressure in the etching chamber 210 includes: when the gas pressure value in the etching chamber 210 is large, the voltage value of the forward voltage and the voltage value of the reverse voltage in the particle removal process are also controlled to be large; when the gas pressure value in the etching chamber 210 is small, the voltage value of the forward voltage and the voltage value of the reverse voltage in the particle removal process are also controlled to be small.

[0049] In this example, when the air pressure in the etching chamber 210 is relatively low, the vacuum pump 230 has a relatively fast pumping rate. At this time, a relatively low 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 vacuum pump 230 has a relatively low pumping rate. At this time, a relatively high 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. The voltage value is regulated in this way, which is conducive to further improving the removal capability of the particles in the transition process.

[0050] As some examples of this embodiment, during the particle removal process, the voltage value of the forward voltage is linearly related to the gas pressure in the etching chamber 210, and the voltage value of the reverse voltage is linearly related to the gas pressure in the etching chamber 210. Setting the applied voltage value to be linearly related to the gas pressure in the etching chamber 210 can make the particle removal capability in the entire etching process more stable.

[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 gas 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 gas 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 may be intermittently changed or approximately considered to be intermittently changed. The intermittent change means that the air pressure in the etching chamber 210 is maintained constant or approximately considered to be maintained constant within a short period of time (for example, within 1 second), and the air pressure jumps between two adjacent time periods. At this time, the particle removal process can be performed synchronously with the time period, that is, the particle removal process is performed once in 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 helpful to ensure that the workpiece 220 to be etched is stably set on the electrostatic suction cup 120, and applying a reverse voltage can generate a repulsive force on the particles attached to the electrostatic suction cup 120, thereby facilitating the particles to detach from the surface of the workpiece 220 to be etched and be extracted by the vacuum pump 230.

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

[0055] As some examples of this embodiment, each application of the reverse voltage to the carrier 110 is performed immediately after the application of the forward voltage. Here, immediately after the application of the forward voltage means that there is no interruption between the application of the forward voltage and the application of the reverse voltage. For example, the forward voltage applied to the carrier 110 can be terminated in an instant, and the reverse voltage can be applied to the carrier 110 at the same time.

[0056] The circuit structure of a conventional electrostatic chuck 120 can only realize application of a forward voltage 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, and the DC-DC converter 130 is used to change the polarity and voltage value of the voltage applied to the carrier 110. When a reverse voltage is applied to the carrier 110, this embodiment changes the polarity of the voltage applied to the carrier 110 through the DC-DC converter 130. The DC-DC converter 130 can adjust the forward voltage applied by the original circuit structure to a reverse voltage, thereby completing the change of the polarity of the applied voltage instantly. By providing the DC-DC converter 130, the manufacturing method of the semiconductor device can be implemented without significantly changing the existing equipment.

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

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

[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 to be equal to the duration of applying the reverse voltage is conducive to ensuring that particles of different charged types can be more fully removed.

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

[0061] As some examples of this embodiment, during the transition process, a forward voltage and a reverse voltage may be alternately applied to the carrier 110. For example, after each application of the forward voltage, a reverse voltage is applied, and then the next forward voltage is applied, and so on. Alternatingly applying the forward voltage and the reverse voltage to the carrier 110 is conducive to ensuring the stable setting of the workpiece 220 to be etched, while improving the probability of removing particles adsorbed by the workpiece 220 to be etched, and improving the yield of the prepared semiconductor device.

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

[0063] As some examples of this embodiment, the voltage value of the reverse voltage applied to the carrier 110 is 300V~1000V. The voltage value refers to the absolute value of the voltage, that is, the voltage value without considering the direction of the current. The voltage value of the reverse voltage is controlled to be 300V~1000V, which can generate a relatively appropriate repulsive force, ensuring that the workpiece 220 to be etched is stably placed while allowing the particles to be effectively removed.

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

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

[0066] In such Figure 2 In the content shown, during the first particle removal treatment to the fifth particle removal treatment, the gas pressure in the etching chamber 210 gradually decreases, that is, P1>P2>P3>P4>P5, and during the fifth particle removal treatment to the sixth particle removal treatment, the gas pressure in the etching chamber 210 rises again, that is, P5<P6.

[0067] Figure 3 For Figure 2 The corresponding voltage curve applied to the carrier 110 is shown in FIG. Figure 3 As shown, during the first particle removal process, at time t0, a forward voltage with a voltage value of V1 is applied to the carrier 110 until the middle moment of the first particle removal process, that is, at time (t1-t0) / 2, and then the polarity of the voltage is changed, and a reverse voltage with a voltage value of V1 is applied to the carrier 110 until the first particle removal process is completed. During the second particle removal process, at time t1, a forward voltage with a voltage value of V2 is applied to the carrier 110 until the middle moment of the second particle removal process, and then the polarity of the voltage is changed, and a reverse voltage with a voltage value of V2 is applied to the carrier 110 until the second particle removal process is completed. Similarly, during the sixth particle removal process, at time t5, a forward voltage with a voltage value of V6 is applied to the carrier 110 until the middle moment of the sixth particle removal process, and then the polarity of the voltage is changed, and a reverse voltage with a voltage value of V6 is applied to the carrier 110 until the sixth particle removal process is completed. It can be understood that in Figure 3 In the figure, V1 indicates that a forward voltage of V1 is applied, and -V1 indicates that a reverse voltage of V1 is applied.

[0068] Reference Figure 3As shown, in the process of the first particle removal treatment, that is, in the time period from t0 to t1, a forward voltage is applied in the first half of the time, at which 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. Assuming that the surface of one side of the carrier 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 carrier 110 in the second half of the time, at which time the surface of one side of the carrier 110 close to the workpiece 220 to be etched is negatively charged, which can generate an instantaneous repulsive force on the particles with negative surface charges, so that the particles move away from the workpiece 220 to be etched, and at this time the particles can be drawn away with the airflow in the etching chamber 210. At the beginning of the second particle removal treatment, a forward voltage and a reverse voltage are applied to the carrier 110 and the voltage value is adjusted according to the change in air pressure, so that the particle removal ability in the two adjacent particle removal treatments can be relatively stable, thereby fully removing the particles on the surface of the second workpiece 220 to be etched. By analogy, by applying a forward voltage and a reverse voltage during each particle removal process, the particles dropped between etching stages can be removed more effectively.

[0069] Further, refer to Figure 3 As shown, Figure 2 Corresponding to the change rule of the air pressure value in, during the process of the first particle removal process to the fifth particle removal process, the voltage values ​​of the forward voltage and the reverse voltage applied to the carrier 110 gradually decrease, that is, V1>V2>V3>V4>V5, and during the process of the fifth particle removal process to the sixth particle removal process, the voltage values ​​of the forward voltage and the reverse voltage applied to the carrier 110 increase, that is, V5<V6. That is, during the particle removal process with a larger air pressure, the voltage value applied to the carrier 110 is also larger. This is conducive to maintaining a relatively stable particle removal capability throughout the entire transition process.

[0070] In this embodiment, during the actual etching process, the DC-DC converter 130 can be set accordingly according to the program of the gas pressure in the etching chamber 210 changing with time, so that the voltage applied to the carrier 110 changes according to the gas pressure.

[0071] Please note that the above embodiments are for illustrative purposes only and are not meant to be limiting of this document.

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

[0073] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0074] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, 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.

Claims

1. A method for manufacturing a semiconductor device, characterized in that: The steps include: Placing a workpiece to be etched on an electrostatic chuck, 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, the electrostatic chuck is synchronously subjected to one or more particle removal processes, wherein the particle removal process includes applying a forward voltage and a reverse voltage with a polarity opposite to the forward voltage to the electrostatic chuck, and during the particle removal process, the voltage value of the forward voltage and the voltage value of the reverse voltage are regulated according to the gas pressure in the etching chamber.

2. The method for manufacturing a semiconductor device according to claim 1, wherein: In the transition process, the gas pressure in the etching chamber gradually changes with time, and the voltage value of the forward voltage and the voltage value of the reverse voltage gradually change with the change of the gas pressure.

3. The method for manufacturing a semiconductor device according to claim 2, wherein: During the particle removal process, the voltage value of the forward voltage is linearly related to the gas pressure in the etching chamber, and the voltage value of the reverse voltage is linearly related to the gas pressure in the etching chamber.

4. The method for manufacturing a semiconductor device according to claim 3, wherein: The voltage value of the forward voltage and the voltage value of the reverse voltage both satisfy the following relationship with the gas 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 gas pressure in the etching chamber, and k and c are both constants.

5. The method for manufacturing a semiconductor device according to any one of claims 1 to 4, characterized in that: During a single particle removal process, the voltage value of the forward voltage is equal to the voltage value of the reverse voltage.

6. The method for manufacturing a semiconductor device according to any one of claims 1 to 4, characterized in that: During a single particle removal process, the duration of applying the forward voltage is equal to the duration of applying the reverse voltage.

7. The method for manufacturing a semiconductor device according to any one of claims 1 to 4, characterized in that: The number of times of the particle removal process is multiple, and the multiple particle removal processes are continuously performed during the transition process.

8. The method for manufacturing a semiconductor device according to claim 6, wherein: During the multiple particle removal processes, the forward voltage and the reverse voltage are applied alternately.

9. The method for manufacturing a semiconductor device according to any one of claims 1 to 4, characterized in that: 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; When a reverse voltage is applied to the electrostatic chuck, the polarity of the voltage applied to the electrostatic chuck is changed by the DC-DC converter.

10. A semiconductor device manufacturing apparatus, 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 disposed 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 gas pressure in the etching chamber.

Images