Base, plasma processing equipment and plasma processing method

Abstract

The present application belongs to the technical field of semiconductor manufacturing equipment, and specifically relates to a base, plasma processing equipment and a plasma processing method, wherein the base includes a base, a first electrode, a second electrode and a third electrode, the top surface of the base includes a bearing area and an edge area surrounding the bearing area, the first electrode is arranged in the base, the second electrode extends from the edge area to the side of the base, and the third electrode is arranged on the side of the second electrode away from the base. When the base is used in a plasma processing device, after the plasma treatment is completed, plasma can be formed on the surfaces of the first electrode and the second electrode to prevent dust particles from falling onto the substrate, and the DC power supply or low-frequency AC power supply connected to the third electrode makes the third electrode positively charged to attract negatively charged dust particles, and then plasma is formed on the surface of the third electrode, which can discharge dust particles adsorbed on the surface of the third electrode, thereby reducing the risk of dust particles falling onto the substrate and improving the yield of the product.

Description

Technical Field

[0001] The present application belongs to the technical field of semiconductor manufacturing equipment, and specifically relates to a base, plasma processing equipment and a plasma processing method. Background Art

[0002] Plasma processing equipment includes plasma etching equipment, plasma enhanced chemical vapor deposition equipment, plasma cleaning equipment, plasma sputtering equipment and plasma ashing equipment.

[0003] The vacuum or low-pressure environment created within the plasma processing equipment's reaction chamber allows dust particles from the outside air to easily enter the chamber, becoming a source of contamination. During operation, dust particles accumulate as reaction residues peel off the inner walls of the chamber. Furthermore, dust particles are generated during the plasma processing process by the mixing reaction of the reactant gases.

[0004] During the plasma treatment process, dust particles are negatively charged by the plasma and are suspended by the balance between the electric field force and gravity. However, when the plasma treatment ends, the electric field force disappears and they fall onto the substrate under the action of gravity, causing serious defects in subsequent processes and reducing the product yield. Summary of the Invention

[0005] The purpose of this application is to provide a base, a plasma processing device and a plasma processing method to reduce the risk of dust particles falling on a substrate and improve the yield of the product.

[0006] In order to achieve the above-mentioned object, the present application provides a susceptor for supporting a substrate in a plasma processing device, the susceptor comprising:

[0007] A base, comprising a top surface and side surfaces, wherein the top surface of the base comprises a carrying area for carrying the substrate and an edge area surrounding the carrying area;

[0008] A first electrode is disposed in the base and corresponds to the bearing area;

[0009] a second electrode extending from the edge region to a side surface of the base, the second electrode being insulated from the first electrode;

[0010] The third electrode is arranged on a side of the second electrode away from the base, and the third electrode is insulated from the second electrode.

[0011] Optionally, the base includes an electrostatic chuck and a support platform, the electrostatic chuck is arranged on the top surface of the support platform, the top surface of the base is the top surface of the electrostatic chuck, and the side surfaces of the base are the side surfaces of the electrostatic chuck and the side surfaces of the support platform.

[0012] Optionally, the first electrode includes the support platform or the electrostatic chuck.

[0013] Optionally, the second electrode includes a second upper electrode located in the edge area, and a second lower electrode extending from a side of the second upper electrode away from the supporting area to a side of the base, and the second upper electrode is connected to the second lower electrode.

[0014] Optionally, the second upper electrode includes a focusing ring.

[0015] Optionally, the connection between the second upper electrode and the second lower electrode includes conductive connection between the second lower electrode and the second upper electrode.

[0016] Optionally, the second electrode includes a second insulating layer, the second insulating layer is formed on an outer surface of the second lower electrode, and the second lower electrode and the second upper electrode are insulated and connected via the second insulating layer.

[0017] Optionally, the insulation between the third electrode and the second electrode includes forming a gap between the third electrode and the second electrode, or the third electrode and the second electrode are insulated and connected.

[0018] Optionally, the outer surface of the second electrode located at the corner between the top surface of the base and the side surface of the base is an arc surface.

[0019] Optionally, the third electrode is made of silicon, or the third electrode includes a third conductive electrode and a third insulating layer located on the surface of the third conductive electrode.

[0020] The present application also provides a plasma processing device, comprising:

[0021] reaction chamber;

[0022] The base is arranged in the reaction chamber.

[0023] Optionally, the plasma processing equipment further includes a baffle, which is disposed between the reaction chamber and a side surface of the base, the baffle being spaced apart from the base, and the third electrode being located on a side of the baffle away from the supporting area.

[0024] Optionally, the top surface and the bottom surface of the base are opposite to each other in the vertical direction, and the distance between the third electrode and the baffle in the vertical direction is greater than 1 cm.

[0025] Optionally, the plasma processing equipment further includes a plasma generating device, and the plasma generating device includes an inductively coupled plasma device, a capacitively coupled plasma device, and a microwave plasma device.

[0026] Optionally, both the first electrode and the second electrode are connected to a radio frequency power source.

[0027] Optionally, the second electrode includes a second upper electrode located in the edge area, and a second lower electrode extending from the second upper electrode away from the supporting area to the side of the base, the second upper electrode is conductively connected or insulated from the second lower electrode, and at least the second lower electrode is connected to the RF power supply.

[0028] Optionally, the third electrode is connected to a radio frequency power supply and one of a low frequency AC power supply and a DC power supply, the DC power supply and the low frequency AC power supply can provide a positive voltage, and the frequency of the low frequency AC power supply is lower than the frequency of the radio frequency power supply.

[0029] Optionally, the plasma processing equipment further includes a purge device for providing a purge gas to purge from the top to the bottom of the base.

[0030] Optionally, the second electrode includes a second upper electrode located in the edge region, and a second lower electrode extending from a side of the second upper electrode away from the supporting region to a side of the base, the second upper electrode being conductively connected or insulatedly connected to the second lower electrode. The plasma device further includes a controller capable of controlling at least the first electrode, the second electrode, the third electrode, and the purge device to perform the following operations:

[0031] S11: performing plasma treatment, wherein the second electrode and the third electrode are floating;

[0032] S12: the first electrode is connected to a radio frequency power source to maintain plasma in the reaction chamber, the second upper electrode is floating or connected to the radio frequency power source, the second lower electrode is connected to the radio frequency power source to form plasma on the surface of the second electrode, and the third electrode is connected to a positive voltage;

[0033] S13: reducing the power of the radio frequency power supply connected to the first electrode to off, connecting the second upper electrode and the second lower electrode to the radio frequency power supply to form plasma on the surface of the second electrode, connecting the third electrode to a positive voltage, and providing a purge gas from the top to the bottom of the base by the purge device;

[0034] S14: The first electrode and the second electrode are grounded or floating, and the third electrode is connected to the RF power supply to form plasma on the surface of the third electrode. The plasma formed on the surface of the third electrode is maintained for a period of time, and the purge is maintained during the period of time.

[0035] The present application also provides a plasma treatment method, comprising:

[0036] S21: using a susceptor to support a substrate, generating plasma in a reaction chamber to perform plasma processing on the substrate;

[0037] S22: After the plasma treatment is completed, maintaining the plasma in the reaction chamber, forming plasma on the side of the susceptor, and providing an adsorption electrode with a positive voltage applied at the bottom of the side of the susceptor;

[0038] S23: performing a purge from top to bottom to reduce the plasma in the reaction chamber until it is closed, while maintaining the plasma on the side of the base and maintaining the positive voltage on the adsorption electrode;

[0039] S24: Stop forming plasma on the side of the base, apply radio frequency voltage to the adsorption electrode to form plasma on the surface of the adsorption electrode, maintain the plasma on the surface of the adsorption electrode for a period of time, and maintain the top-down purge during the period of time.

[0040] The base, plasma processing equipment and plasma processing method disclosed in this application have the following beneficial effects:

[0041] In the present application, the base includes a base, a first electrode, a second electrode and a third electrode. The base includes a top surface and a side surface. The top surface of the base includes a supporting area for supporting a substrate, and an edge area surrounding the supporting area. The first electrode is arranged in the base, the second electrode extends from the edge area to the side of the base, and the third electrode is arranged on the side of the second electrode away from the base. When the base is used in a plasma processing device, after the plasma treatment is completed, plasma can be formed on the surfaces of the first electrode and the second electrode to prevent dust particles from falling onto the substrate. The DC power supply or low-frequency AC power supply connected to the third electrode makes the third electrode positively charged to attract negatively charged dust particles. Then, plasma is formed on the surface of the third electrode, which can discharge dust particles adsorbed on the surface of the third electrode, thereby reducing the risk of dust particles falling onto the substrate and improving the yield of the product.

[0042] Other features and advantages of the present application will become apparent from the following detailed description, or may be learned in part by practice of the present application.

[0043] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] The accompanying drawings are incorporated into and constitute a part of the specification, illustrate embodiments consistent with the present application, and together with the specification, are used to explain the principles of the present application. Obviously, the drawings described below are only some embodiments of the present application, and those skilled in the art can derive other drawings based on these drawings without inventive effort.

[0045] Figure 1 It is a structural diagram of the base in the embodiment of the present application.

[0046] Figure 2 It is a structural schematic diagram of the plasma processing equipment in an embodiment of the present application.

[0047] Figure 3 This is a schematic diagram of plasma treatment of a substrate in an embodiment of the present application.

[0048] Figure 4 This is a schematic diagram of activating the second electrode in an embodiment of the present application.

[0049] Figure 5 This is a schematic diagram of stopping the first electrode in an embodiment of the present application.

[0050] Figure 6 Schematic diagram of the discharge of dust particles in an embodiment of the present application.

[0051] Figure 7 Schematic diagram of the plasma treatment process in the embodiment of the present application.

[0052] Description of reference numerals:

[0053] 100, base; 110, base; 111, electrostatic chuck; 1111, ceramic body; 1112, electrostatic electrode; 112, support platform; 120, first electrode; 121, first conductive electrode; 130, second electrode; 131, second upper electrode; 132, second lower electrode; 133, second insulating layer; 140, third electrode;

[0054] 200, reaction chamber; 210, top plate; 220, bottom plate; 221, exhaust port; 230, side plate;

[0055] 310, RF power supply; 320, DC power supply; 330, matching device;

[0056] 400, baffle; 500, insulation plate; 610, purge device; 620, gate valve; 700, substrate. DETAILED DESCRIPTION

[0057] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided so that this application will be thorough and complete and will fully convey the concepts of the example embodiments to those skilled in the art.

[0058] In addition, described feature, structure or characteristic can be combined in one or more embodiments in any suitable manner.In the following description, many specific details are provided so as to provide a full understanding of the embodiments of the present application. However, it will be appreciated by those skilled in the art that the technical scheme of the present application can be put into practice without one or more of the specific details, or other methods, components, devices, steps etc. can be adopted. In other cases, known methods, devices, implementations or operations are not shown or described in detail to avoid blurring the various aspects of the application.

[0059] The present application is further described below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the technical features involved in the various embodiments of the present application described below can be combined with each other as long as they do not conflict with each other. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be understood as limiting the present application.

[0060] See also Figure 1 and Figure 2 As shown, in this embodiment, the susceptor 100 is used in a plasma processing apparatus to support a substrate 700. The susceptor 100 includes a base 110, a first electrode 120, a second electrode 130, and a third electrode 140. The base 110 includes a top surface and side surfaces. The top surface of the base 110 includes a supporting area for supporting the substrate 700 and an edge area surrounding the supporting area.

[0061] The first electrode 120 is disposed within the base 110 and corresponds to the supporting area. The second electrode 130 extends from the edge region to the side of the base 110 and is insulated from the first electrode 120. The third electrode 140 is disposed on the side of the second electrode 130 away from the base 110 and is insulated from the second electrode 130. In other words, the portion of the second electrode 130 that extends to the side of the base 110 is located between the side of the base 110 and the third electrode 140.

[0062] The plasma processing apparatus includes a base 100 and a reaction chamber 200. The base 100 is disposed within the reaction chamber 200. The vertical direction is defined by the top and bottom surfaces of the base 110 relative to each other, and the horizontal direction is defined by the inner and outer sides of the base 110. A first plasma processing space P1 is formed between the first electrode 120 and the reaction chamber 200. A second plasma processing space P2 is formed between the combination of the first electrode 120 and the second electrode 130 and the reaction chamber 200. A third plasma processing space P3 is formed between the third electrode 140 and the reaction chamber 200.

[0063] Phase 1: During the plasma treatment process, a first plasma is formed between the first electrode 120 and the wall of the reaction chamber 200. Negatively charged particles accumulate in the pre-sheath between the ion sheath and the plasma and do not fall onto the substrate 700. Figure 3 shown.

[0064] Second stage: After the plasma treatment is completed, the RF power supply 310 connected to the first electrode 120 continues to supply power, and the RF power supply 310 connected to the second electrode 130 starts to supply power. Plasma is formed on the surface of the first electrode 120 and the surface of the second electrode 130. The DC power supply 320 or low-frequency AC power supply connected to the third electrode 140 makes the third electrode 140 positively charged to attract negatively charged dust particles, such as Figure 4 shown.

[0065] The third stage: the power output to the first electrode 120 is reduced to off (for example, the power output to the first electrode 120 is gradually reduced until the power of the first electrode 120 is turned off at the end of the third stage). During the power reduction process, dust particles can be gradually attracted to the third electrode 140. At this time, the plasma is P2, such as Figure 5 As shown, after the attraction is completed, the plasma maintained by the first electrode 120 can be turned off.

[0066] The fourth stage: the power supply to the first electrode 120 and the second electrode 130 is stopped, the DC power supply 320 or the low-frequency AC power supply connected to the third electrode 140 is stopped, and the RF power supply 310 connected to the third electrode 140 starts to supply power, forming a plasma P3 on the surface of the third electrode 140, and discharging dust particles adsorbed on the surface of the third electrode 140, such as Figure 6 shown.

[0067] It should be noted that Figure 3-6 The width of the plasma in the represents its plasma density, not the actual boundary of the plasma.

[0068] During plasma processing, dust particles are negatively charged by the plasma, causing them to remain suspended due to the balance between the electric field and gravity. In existing technologies, after plasma processing is completed, the plasma generator shuts down, the electric field disappears, and the dust particles fall onto substrate 700 under the influence of gravity, causing serious defects in subsequent processes and reducing product yield.

[0069] In this embodiment, the base 100 includes a base 110, a first electrode 120, a second electrode 130, and a third electrode 140. The base 110 includes a top surface and side surfaces. The top surface of the base 110 includes a supporting area for supporting the substrate 700 and an edge area surrounding the supporting area. The first electrode 120 is disposed within the base 110, the second electrode 130 extends from the edge area to the side of the base 110, and the third electrode 140 is disposed on the side of the second electrode 130 away from the base 110. When the base 100 is used in a plasma processing device, after the plasma processing is completed, plasma can be formed on the surfaces of the first electrode 120 and the second electrode 130 to prevent dust particles from falling onto the substrate 700. The third electrode 140 is connected to a DC power supply 320 or a low-frequency AC power supply to positively charge the third electrode 140, thereby attracting negatively charged dust particles. Plasma is then formed on the surface of the third electrode 140, which can expel dust particles adsorbed on the surface of the third electrode 140, thereby reducing the risk of dust particles falling onto the substrate 700 and improving product yield.

[0070] In some embodiments, the base 110 includes an electrostatic chuck 111 and a support 112. The electrostatic chuck 111 is arranged on the top surface of the support 112. The top surface of the base 110 is the top surface of the electrostatic chuck 111. The side surfaces of the base 110 are the side surfaces of the electrostatic chuck 111 and the side surfaces of the support 112.

[0071] The electrostatic chuck 111 may include a ceramic body 1111 and an electrostatic electrode 1112 embedded in the ceramic body 1111. The electrostatic electrode 1112 may be connected to a DC power supply 320, and a DC voltage applied from the DC power supply 320 to the electrostatic electrode 1112 generates an electrostatic force, thereby adsorbing the substrate 700 onto the supporting area of the electrostatic chuck 111.

[0072] The base 112 is generally cylindrical in shape, and the ceramic body 1111 is disposed on the base 112. The ceramic body 1111 is cylindrical as a whole, and the bearing area and the edge area are on the same horizontal plane. Alternatively, the ceramic body 1111 may include an upper cylinder and a lower cylinder that are arranged in an overlapping manner, with the diameter of the upper cylinder being smaller than that of the lower cylinder. The bearing area is the top surface of the upper cylinder, and the edge area is a portion of the top surface of the lower cylinder.

[0073] The base 110 includes an electrostatic chuck 111 and a support 112 . The electrostatic chuck 111 can adsorb the substrate 700 by electrostatic force, thereby preventing the substrate 700 from shifting during plasma processing.

[0074] In some embodiments, the first electrode 120 includes a first conductive electrode 121. The first conductive electrode 121 can be disposed in the support 112 or the ceramic body 1111. The first electrode 120 includes the support 112 or the electrostatic chuck 111. Furthermore, the support 112 can also be made of a conductive or semiconductor material and connected to the RF power supply 310 to serve as the first electrode 120.

[0075] The first electrode 120 includes a support platform 112 or an electrostatic chuck 111. A first plasma processing space can be formed between the first electrode 120 and the reaction chamber 200 for performing plasma treatment on the substrate 700. The plasma treatment includes plasma etching, plasma enhanced chemical vapor deposition, plasma cleaning, plasma sputtering, and plasma ashing.

[0076] In some embodiments, the second electrode 130 includes a second upper electrode 131 located in the edge region, and a second lower electrode 132 extending from the side of the second upper electrode 131 away from the supporting region to the side of the base 110. The second upper electrode 131 is electrically connected or insulated from the second lower electrode 132. The second upper electrode 131 is disposed around the electrostatic chuck 111, and the second lower electrode 132 is disposed around the electrostatic chuck 111 and the support platform 112.

[0077] The second electrode 130 includes a second upper electrode 131 and a second lower electrode 132. The second upper electrode 131 and the second lower electrode 132 can be applied with the same or different voltages as needed. For example, different voltages can be applied to the second upper electrode 131 and the second lower electrode 132 during and after plasma treatment of the substrate 700. After plasma treatment of the substrate 700, the second upper electrode 131 and the second lower electrode 132 can be applied with the same or different voltages as needed.

[0078] In some embodiments, the second upper electrode 131 includes a focus ring, an annular structure surrounding the first electrode 120. The focus ring can be floating or connected to a power source. The floating focus ring offers a simple structure, eliminating the need for additional power connections and complex circuit design, reducing device cost and complexity. Once the focus ring is connected to a power source, the electric field distribution around the focus ring can be altered by adjusting the voltage provided by the power source, thereby more precisely controlling the trajectory and distribution of ions in the plasma.

[0079] During plasma treatment of substrate 700, second upper electrode 131 acts as a focusing ring, regulating the plasma's electric field distribution, ion trajectory, and plasma density distribution, improving the uniformity of plasma distribution and thus enhancing the process consistency of plasma treatment. After plasma treatment of substrate 700, plasma is generated on the surfaces of second upper electrode 131 and second lower electrode 132, preventing dust particles from falling and discharging them.

[0080] In some embodiments, the connection between the second upper electrode 131 and the second lower electrode 132 includes conductive connection between the second lower electrode 132 and the second upper electrode 131 .

[0081] When the second upper electrode 131 is conductively connected to the second lower electrode 132 , the RF power supply 310 can be connected to one of the second upper electrode 131 and the second lower electrode 132 , so that plasma can be generated on the surfaces of both the second upper electrode 131 and the second lower electrode 132 .

[0082] In some embodiments, the second upper electrode 131 and the second lower electrode 132 are insulated and connected. Materials for the second upper electrode 131 include silicon (Si), glassy carbon, quartz, and aluminum (Al). When the second upper electrode 131 is made of a semiconductor material or a conductive material, the second electrode 130 may further include a first insulating layer formed on the outer surface of the second upper electrode 131. The first insulating layer may be made of aluminum oxide (Al2O3), silicon dioxide (SiO2), or yttrium oxide (Y2O3). When the second upper electrode 131 is made of an insulating material, the first insulating layer may be omitted.

[0083] It should be noted that when the second upper electrode 131 comprises a conductor or semiconductor material and a first insulating layer is formed on its surface, the second upper electrode 131 can be loaded with an RF power source to form a plasma on its surface during the second and third stages, or the second upper electrode 131 can be left floating. When the second upper electrode 131 is made of an insulating material, since both the first electrode 120 and the second lower electrode 132 are loaded with an RF power source to generate plasma during the second and third stages, the plasma on the surfaces of the first electrode 120 and the second lower electrode 132 can be continuous, and the negatively charged dust ions remain trapped in the pre-sheath and cannot fall onto the wafer surface. That is, although the second upper electrode 131 is called an "electrode," it can still be made of an insulating material and can be a focusing ring made of an insulating material.

[0084] The second lower electrode 132 may be made of materials including doped silicon, glassy carbon, and aluminum. The material of the second lower electrode 132 may be the same as or different from the material of the second upper electrode 131. The second electrode 130 may further include a second insulating layer 133 formed on the outer surface of the second lower electrode 132. The second lower electrode 132 and the second upper electrode 131 are insulated and connected via the second insulating layer 133. The second insulating layer 133 may be made of materials including aluminum oxide, silicon dioxide, or yttrium oxide. The second lower electrode 132 may be made of conductive materials such as glassy carbon and aluminum, but is not limited thereto. The second lower electrode 132 may also be made of semiconductor materials such as silicon, depending on the specific circumstances.

[0085] When the second upper electrode 131 is insulated from the second lower electrode 132, the RF power supply 310 can be connected to the second lower electrode 132. Since plasma can be generated on the surfaces of the first electrode 120 and the second lower electrode 132, plasma can be maintained even if no voltage is applied to the second upper electrode 131. At this time, the second upper electrode 131 can be insulated, or the second upper electrode 131 is insulated and its surface is covered with a first insulating layer, and the second upper electrode 131 is floating.

[0086] In some embodiments, the third electrode 140 is made of doped silicon and is connected to a DC power source 320 or a low-frequency AC power source to impart a positive charge to the third electrode 140. In other embodiments, the third electrode 140 includes a third conductive electrode and a third insulating layer, with the third insulating layer formed on the outer surface of the third conductive electrode. The third conductive electrode can be made of materials such as glassy carbon and aluminum, while the third insulating layer can be made of aluminum oxide, silicon dioxide, or yttrium oxide.

[0087] Even if a third insulating layer is formed on the outer surface of the third conductive electrode, the third electrode 140 can be positively charged by a low-frequency AC power source without affecting the absorption of dust particles by the third electrode 140. Forming the third insulating layer on the surface of the third conductive electrode protects the third conductive electrode. The third insulating layer is made of a high-temperature resistant and stable material, preventing the third electrode 140 from becoming a source of contamination.

[0088] It should be noted that the third electrode 140 is positively charged to attract negatively charged dust particles, that is, the positive voltage applied thereto is sufficient to release negatively charged ions from the pre-sheath. It should also be noted that when a low-frequency AC power source is applied to the third electrode 140, the positive voltage can be the average value of the AC power source.

[0089] In some embodiments, the third electrode 140 is insulated from the second electrode 130. For example, a gap is formed between the third electrode 140 and the second electrode 130, thereby isolating the third electrode 140 from the second electrode 130. In other embodiments, the third electrode 140 and the second electrode 130 are insulated by an insulating layer, which is the second insulating layer 133 or the third insulating layer. The thickness of the insulating layer between the third electrode 140 and the second electrode 130 must be sufficient to block high-frequency alternating current. For example, the thickness of the insulating layer between the third electrode 140 and the second electrode 130 is greater than 50 μm.

[0090] The third electrode 140 is insulated and connected to the second electrode 130 via an insulating layer. The third electrode 140 and the second electrode 130 are connected as one. When the base 100 is used in a plasma processing device, the installation and fixing structure of the third electrode 140 can be omitted or simplified, which is beneficial to reducing the manufacturing cost of the plasma processing equipment.

[0091] In some embodiments, the outer surface of the second electrode 130 located at the corner between the top surface of the base 110 and the side surface of the base 110 is an arc surface. The curvature of the arc surface is 2 cm to 10 cm, for example, the curvature of the arc surface is 2 cm, 5 cm, or 10 cm. The second upper electrode 131 is disposed around the electrostatic chuck 111, and the radial width of the second upper electrode 131 is 5 mm to 5 cm. Preferably, the radial width of the second upper electrode 131 is 1 cm to 3 cm.

[0092] The outer surface of the second electrode 130 located at the corner between the top surface of the base 110 and the side surface of the base 110 is an arc surface, which can prevent the second electrode 130 from blocking dust particles from moving toward the third electrode 140.

[0093] The present application also provides a plasma processing apparatus, comprising the susceptor 100 and reaction chamber 200 disclosed above, wherein the susceptor 100 is disposed within the reaction chamber 200. The reaction chamber 200 may be an anodized aluminum cylindrical container. The reaction chamber 200 may include a top plate 210 and a bottom plate 220 disposed vertically opposite each other, and a side plate 230 surrounding and connected to the top and bottom plates 210 and 220. The susceptor 100 may be disposed on the bottom plate 220 via an insulating plate 500. A gate valve 620 is also disposed on the side plate 230, through which a substrate 700 may be moved into or out of the reaction chamber 200.

[0094] When the base 100 is used in a plasma processing device, after the plasma treatment is completed, plasma can be formed on the surfaces of the first electrode 120 and the second electrode 130 to prevent dust particles from falling onto the substrate 700. The DC power supply 320 or low-frequency AC power supply connected to the third electrode 140 makes the third electrode 140 positively charged to attract negatively charged dust particles, and then plasma is formed on the surface of the third electrode 140, which can discharge dust particles adsorbed on the surface of the third electrode 140, thereby reducing the risk of dust particles falling onto the substrate 700 and improving the product yield.

[0095] In some embodiments, the plasma processing apparatus further includes a baffle 400 disposed between the reaction chamber 200 and a side surface of the base 110. The baffle 400 is spaced apart from the base 100 and connected to the inner wall of the side plate 230. The third electrode 140 is located on a side of the baffle 400 away from the supporting area. The baffle 400 may be an anodized aluminum structural member.

[0096] The third electrode 140 is arranged on the side of the baffle 400 away from the supporting area. Plasma is formed on the surface of the third electrode 140. When dust particles adsorbed on the surface of the third electrode 140 are discharged, the baffle 400 can block the dust particles and prevent the dust particles from returning to the top of the baffle 400 and falling onto the substrate 700.

[0097] When plasma is formed on the surface of the second electrode 130 , the plasma passes through between the baffle 400 and the second electrode 130 .

[0098] In some embodiments, the vertical distance between the third electrode 140 and the baffle 400 is greater than 1 cm. For example, the vertical distance between the third electrode 140 and the baffle 400 is 1 cm to 2 cm. Preferably, the vertical distance between the third electrode 140 and the baffle 400 is 3 cm to 5 cm, or greater than 5 cm.

[0099] A sufficient gap is formed between the third electrode 140 and the baffle 400 to prevent dust particles from returning to the top of the baffle 400 and falling onto the substrate 700 .

[0100] In some embodiments, the plasma processing apparatus further includes a plasma generating device, including an inductively coupled plasma (ICP) device, a capacitively coupled plasma (CCP) device, and a microwave plasma (MP) device. This application does not limit the specific structure of the plasma generating device.

[0101] It can be understood that the plasma generating device is a collection of components used to work together with the first electrode 120 to generate plasma in the chamber for performing the first stage of plasma treatment on the substrate. For example, in an embodiment where the plasma generating device includes an ICP, the plasma generating device includes an inductor coil wound outside the reaction chamber 200 and a radio frequency power supply connected to the inductor coil.

[0102] The base 100 can be used in various types of plasma processing equipment, thereby improving the versatility of components.

[0103] In some embodiments, the first electrode 120 and the second electrode 130 are both connected to the RF power source 310 via a matcher 330. The frequency of the RF power source 310 connected to the first electrode 120 is 100 kHz to 13.56 MHz, and the frequency of the RF power source 310 connected to the second electrode 130 is 100 kHz to 13.56 MHz. Taking the plasma generating device as a capacitively coupled plasma device as an example, the top plate 210 can be connected to the RF power source 310 via a matcher 330, and the frequency of the RF power source 310 connected to the top plate 210 can be 27 MHz to 100 MHz. The side plate 230 of the reaction chamber 200 can be grounded.

[0104] The first electrode 120 and the second electrode 130 are connected to a radio frequency power supply 310 of the same frequency. The plasma formed by the first electrode 120 is used to process the substrate 700. After the plasma treatment is completed, the plasma formed by the second electrode 130 is used to transfer dust particles and prevent dust particles from falling on the substrate 700. The power required to maintain the plasma on the surface of the second electrode 130 is less than the power required to maintain the plasma on the surface of the first electrode 120. The first electrode 120 and the second electrode 130 can share a radio frequency power supply 310, and a power divider can be used to allocate a small amount of power to the second electrode 130.

[0105] In some embodiments, the second electrode 130 includes a second upper electrode 131 and a second lower electrode 132. The second upper electrode 131 is conductively connected or insulated from the second lower electrode 132. At least the second lower electrode 132 is connected to the RF power source 310. In other words, the second lower electrode 132 is connected to the RF power source 310, and the second upper electrode 131 can be floating, connected to the RF power source 310, or connected to another DC power source 320 or an AC power source.

[0106] Because plasma can be generated on both the surfaces of the first electrode 120 and the second lower electrode 132, the second upper electrode 131 can maintain continuous plasma even without applying a voltage. During plasma processing of the substrate 700, the second upper electrode 131 acts as a focusing ring. Depending on the need to improve the uniformity of plasma distribution and thus enhance the process consistency of the plasma processing, the second upper electrode 131 can be floated or connected to a power source.

[0107] In some embodiments, the third electrode 140 is connected to the RF power supply 310 and one of the low-frequency AC power supply and the DC power supply 320 . The DC power supply 320 and the low-frequency AC power supply can provide positive voltages. The frequency of the low-frequency AC power supply is lower than the frequency of the RF power supply 310 .

[0108] Plasma is formed on the surface of the third electrode 140 to expel dust particles adsorbed on the surface of the third electrode 140. Since the plasma formed on the surface of the third electrode 140 is only used to remove dust particles from the third electrode 140, the third electrode 140 can share a radio frequency power supply 310 with the first electrode 120, and a power divider can be used to allocate a small amount of power to the third electrode 140.

[0109] When the third electrode 140 is positively charged to attract negatively charged dust particles, the third electrode 140 is connected to the DC power supply 320 and the low-frequency AC power supply. The frequency of the low-frequency AC power supply is 50Hz~100kHz. Preferably, the frequency of the low-frequency AC power supply is 50Hz~1kHz, that is, the low-frequency AC power supply makes the third electrode 140 positively charged, but does not form plasma on the surface of the third electrode 140.

[0110] A first plasma forms between the first electrode 120 and the reaction chamber 200. Electrons, due to their light mass, can easily follow changes in the electric field. However, ions, with a mass approximately 100,000 times that of electrons, cannot move in time with the frequency of the RF power supply 310. As a result, electrons gradually accumulate at the first electrode 120, gradually biasing the first electrode 120 toward a negative potential, forming a DC bias voltage Vdc. The magnitude of the DC bias Vdc depends at least on the power of the RF power supply 310. When the third electrode 140 is positively charged and attracts negatively charged dust particles, the positive voltage is greater than the DC bias Vdc formed by the first plasma and the DC bias Vdc formed by the second plasma. This prevents negatively charged dust particles from being trapped in the pre-sheath, thereby improving the efficiency of the third electrode 140's positive charge in attracting negatively charged dust particles.

[0111] In some embodiments, the plasma processing apparatus further includes a purge device 610 for providing a purge gas to purge from the top to the bottom of the susceptor 100. The purge device 610 can be connected to the top plate 210, and the purge gas can be purged from the top to the bottom of the susceptor 100 through the top plate 210 and the top. At least one exhaust port 221 can be provided in the area surrounding the susceptor 100 on the bottom plate 220.

[0112] The purge device can provide a purge airflow to move the dust particles toward the third electrode 140 in the third and fourth stages.

[0113] During plasma processing of substrate 700, the purge gas pressure is p1 and the exhaust velocity is V1. When the third electrode 140 is positively charged and attracts negatively charged dust particles, the purge gas pressure can be increased to p2 and the exhaust velocity can be increased to V2, causing the dust particles to move toward the third electrode 140 along the pre-sheath formed by the second plasma and be adsorbed onto the third electrode 140. When plasma forms on the surface of the third electrode 140, causing the dust particles to leave the third electrode 140, the purge gas pressure p2 and the exhaust velocity V2 can be maintained, allowing the dust particles to be discharged from the reaction chamber 200 along with the purge gas flow.

[0114] In some embodiments, the plasma apparatus further includes a controller (not shown), which can control at least the first electrode 120 , the second electrode 130 , the third electrode 140 , and the purge device 610 to perform the following operations:

[0115] S11: Plasma treatment is performed, in which the second electrode 130 and the third electrode 140 are floated.

[0116] like Figure 3 As shown, a first plasma is formed between the first electrode 120 and the reaction chamber 200, and the substrate 700 is subjected to plasma treatment. Negatively charged particles accumulate in the pre-sheath between the ion sheath and the plasma and do not fall onto the substrate 700. The second electrode 130 and the third electrode 140 float.

[0117] S12: The first electrode 120 is connected to the RF power supply 310 to maintain the plasma in the reaction chamber 200, the second upper electrode 131 is floating or connected to the RF power supply 310, the second lower electrode 132 is connected to the RF power supply 310 to form plasma on the surface of the second electrode 130, and the third electrode 140 is connected to a positive voltage.

[0118] like Figure 4 As shown, after the plasma treatment is completed, the RF power supply 310 connected to the first electrode 120 continues to supply power, the second upper electrode 131 floats or is connected to the RF power supply 310, and the second lower electrode 132 is connected to the RF power supply 310 to form plasma on the surface of the second electrode 130 to prevent dust particles from falling on the substrate 700 or the second electrode 130. The DC power supply 320 or low-frequency AC power supply connected to the third electrode 140 makes the third electrode 140 positively charged to attract negatively charged dust particles.

[0119] S13: Reduce the power of the RF power supply 310 connected to the first electrode 120 to off, connect the second upper electrode 131 and the second lower electrode 132 to the RF power supply 310 to form plasma on the surface of the second electrode 130, connect the third electrode 140 to a positive voltage, and provide a purge gas from the top to the bottom of the base 100 to provide airflow for purge.

[0120] Optionally, in step S12 , a purge gas is also provided to provide an airflow purge from the top to the bottom of the susceptor 100 , and in step S13 , the air pressure and airflow speed of the purge gas are both greater than those in step S12 .

[0121] like Figure 5 As shown, the power output to the first electrode 120 is reduced to off (for example, turned off at the end of step S13, or step S13 also includes a stage after the power output to the first electrode 120 is turned off), the second upper electrode 131 and the second lower electrode 132 are both connected to the RF power supply 310 to form plasma on the surface of the second electrode 130 to prevent dust particles from falling on the substrate 700 or the second electrode 130, and the DC power supply 320 or low-frequency AC power supply connected to the third electrode 140 makes the third electrode 140 positively charged to attract negatively charged dust particles. The dust particles move toward the third electrode 140 with the purge airflow and are adsorbed on the third electrode 140.

[0122] S14: The first electrode 120 and the second electrode 130 are grounded or floating, and the third electrode 140 is connected to the RF power supply 310 to form plasma on the surface of the third electrode 140. The plasma formed on the surface of the third electrode 140 is maintained for a period of time, and the purge is maintained during the period of time.

[0123] like Figure 6 As shown, power supply to the first electrode 120 and the second electrode 130 is stopped, and power supply from the DC power supply 320 or the low-frequency AC power supply connected to the third electrode 140 is stopped. The RF power supply 310 connected to the third electrode 140 starts to supply power, and plasma is formed on the surface of the third electrode 140. The dust particles adsorbed on the surface of the third electrode 140 are negatively charged again, thereby being confined in the pre-sheath, leaving the third electrode 140, and being discharged from the reaction chamber 200 along with the purge gas flow.

[0124] After the plasma treatment is completed, the dust particles are first adsorbed onto the third electrode 140, and then plasma is formed on the surface of the third electrode 140, which can discharge the dust particles adsorbed on the surface of the third electrode 140, thereby reducing the risk of dust particles falling onto the substrate 700 and improving the product yield.

[0125] Optionally, after a period of time, the top-down purge is stopped.

[0126] It can be understood that after step S11, since the plasma treatment of the substrate has been completed, but plasma needs to be formed, in steps S12-S14, that is, the second to fourth stages described above and steps S22-S24 described below, the reaction gas is stopped from being introduced into the reaction chamber 200, and an inert gas is introduced, and the plasma is maintained by the RF voltage applied to the first electrode 120.

[0127] Optionally, during steps S12-S14, or the second to fourth stages, or steps S22-S24 described later, the pressure in reaction chamber 200 may be increased during the introduction of the inert gas. Optionally, during steps S13-S14, or the third to fourth stages, or steps S23-S24 described later, the plasma density may be lower than during plasma processing of the substrate.

[0128] This application also provides a plasma treatment method, see Figure 7 As shown, the plasma treatment method includes:

[0129] S21: Using the susceptor 100 to support the substrate 700, generating plasma in the reaction chamber 200 to perform plasma treatment on the substrate 700;

[0130] S22: After the plasma treatment is completed, the plasma in the reaction chamber 200 is maintained, plasma is formed on the side of the susceptor 100, and an adsorption electrode with a positive voltage applied is provided at the bottom of the side of the susceptor 100;

[0131] S23: Purge from top to bottom to reduce the plasma in the reaction chamber 200 to shut down, while maintaining the plasma on the side of the susceptor 100 and the positive voltage on the adsorption electrode;

[0132] S24: Stop forming plasma on the side of the base 100, apply radio frequency voltage to the adsorption electrode to form plasma on the surface of the adsorption electrode, maintain the plasma on the surface of the adsorption electrode for a period of time, and maintain top-down purge for a period of time.

[0133] Optionally, after a period of time, the top-down purge is stopped.

[0134] It can be understood that the plasma in the reaction chamber 200 refers to the plasma above the substrate 700 .

[0135] After the plasma treatment is completed, the first electrode 120 is used to maintain the plasma in the reaction chamber 200, forming a plasma on the side of the base 100. Negatively charged dust particles accumulate in the pre-sheath between the ion sheath and the plasma and do not fall onto the substrate 700. The adsorption electrode can adsorb the dust particles. The dust particles move toward the adsorption electrode with the purge gas flow and are adsorbed on the adsorption electrode. Finally, a radio frequency voltage is applied to the adsorption electrode to form a plasma on the surface of the adsorption electrode. The dust particles adsorbed on the adsorption electrode leave the adsorption electrode and are discharged from the reaction chamber 200 with the purge gas flow. Therefore, the plasma treatment method disclosed in this application can discharge dust particles from the reaction chamber 200, reducing the risk of dust particles falling on the substrate 700 and improving the product yield.

[0136] The terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature identified with "first," "second," etc., may explicitly or implicitly include one or more of such features. Throughout the description of this application, "plurality" means two or more, unless otherwise specifically defined.

[0137] In this application, unless otherwise specified or limited, terms such as "assembly" and "connection" should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection; direct connection, or indirect connection through an intermediate medium; internal communication between two components, or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0138] In the description of this specification, the reference terms "some embodiments", "exemplarily", etc. mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.

[0139] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application. Therefore, any changes or modifications made in accordance with the claims and description of the present application should fall within the scope of the patent application.

Claims

1. A plasma processing device, comprising a base, wherein the base is used to support a substrate in the plasma processing device, characterized in that: The base comprises: A base, comprising a top surface and side surfaces, wherein the top surface of the base comprises a carrying area for carrying the substrate and an edge area surrounding the carrying area; A first electrode is disposed in the base and corresponds to the bearing area; a second electrode extending from the edge region to a side surface of the base, the second electrode being insulated from the first electrode, and capable of forming plasma on a surface of the second electrode to float dust particles; a third electrode, disposed on a side of the second electrode away from the base, the third electrode being insulated from the second electrode; The plasma processing equipment also includes a reaction chamber and a baffle. The base is arranged in the reaction chamber, and the baffle is arranged between the reaction chamber and the side of the base. The baffle and the base are spaced apart. The third electrode is located on the side of the baffle away from the supporting area. The third electrode can adsorb the dust particles floating from the second electrode and plasma can be formed on the surface of the third electrode to discharge the adsorbed dust particles.

2. The plasma processing apparatus according to claim 1, wherein The base includes an electrostatic chuck and a support platform. The electrostatic chuck is arranged on the top surface of the support platform. The top surface of the base is the top surface of the electrostatic chuck. The side surfaces of the base are the side surfaces of the electrostatic chuck and the side surfaces of the support platform.

3. The plasma processing equipment according to claim 2, wherein The first electrode includes the platform or the electrostatic chuck.

4. The plasma processing apparatus according to claim 1, wherein: The second electrode includes a second upper electrode located in the edge area and a second lower electrode extending from a side of the second upper electrode away from the supporting area to a side of the base, and the second upper electrode is connected to the second lower electrode.

5. The plasma processing equipment according to claim 4, wherein The second upper electrode includes a focus ring.

6. The plasma processing apparatus according to claim 4, wherein: The second upper electrode is connected to the second lower electrode, and the second lower electrode is conductively connected to the second upper electrode.

7. The plasma processing apparatus according to claim 4, wherein: The second electrode includes a second insulating layer formed on an outer surface of the second lower electrode, and the second lower electrode and the second upper electrode are insulated and connected via the second insulating layer.

8. The plasma processing equipment according to claim 1 or 7, wherein: The insulation between the third electrode and the second electrode includes forming a gap between the third electrode and the second electrode, or the third electrode and the second electrode are insulated and connected.

9. The plasma processing equipment according to claim 1 or 4, characterized in that: The outer surface of the second electrode located at the corner between the top surface of the base and the side surface of the base is an arc surface.

10. The plasma processing apparatus according to claim 1, wherein The third electrode is made of silicon, or the third electrode includes a third conductive electrode and a third insulating layer located on the surface of the third conductive electrode.

11. The plasma processing apparatus according to claim 1, wherein The top surface and the bottom surface of the base are opposite to each other in the vertical direction, and the distance between the third electrode and the baffle in the vertical direction is greater than 1 cm.

12. The plasma processing apparatus according to claim 1, wherein The plasma processing equipment further includes a plasma generating device, which includes an inductively coupled plasma device, a capacitively coupled plasma device, and a microwave plasma device.

13. The plasma processing apparatus according to claim 12, wherein: The first electrode and the second electrode are both connected to a radio frequency power source.

14. The plasma processing apparatus according to claim 13, wherein: The second electrode includes a second upper electrode located in the edge area, and a second lower electrode extending from the second upper electrode away from the supporting area to the side of the base. The second upper electrode is conductively connected or insulated from the second lower electrode, and at least the second lower electrode is connected to the RF power supply.

15. The plasma processing apparatus according to claim 1, wherein When the third electrode is used to adsorb the dust particles floated by the second electrode, the third electrode is connected to one of a low-frequency AC power supply and a DC power supply, the DC power supply and the low-frequency AC power supply can provide a positive voltage, and the frequency of the low-frequency AC power supply is lower than the frequency of the RF power supply; when the third electrode is used to discharge the adsorbed dust particles, the third electrode is connected to the RF power supply.

16. The plasma processing equipment according to any one of claims 1 or 11 to 15, wherein: The plasma processing equipment further includes a purging device for providing a purging gas to purge from the top to the bottom of the susceptor.

17. The plasma processing apparatus according to claim 16, wherein: The second electrode includes a second upper electrode located in the edge region, and a second lower electrode extending from a side of the second upper electrode away from the supporting region to a side of the base, the second upper electrode being conductively connected or insulatedly connected to the second lower electrode. The plasma processing apparatus further includes a controller capable of controlling at least the first electrode, the second electrode, the third electrode, and the purge device to perform the following operations: S11: performing plasma treatment, wherein the second electrode and the third electrode are floating; S12: the first electrode is connected to a radio frequency power source to maintain plasma in the reaction chamber, the second upper electrode is floating or connected to the radio frequency power source, the second lower electrode is connected to the radio frequency power source to form plasma on the surface of the second electrode, and the third electrode is connected to a positive voltage; S13: reducing the power of the radio frequency power supply connected to the first electrode to off, connecting the second upper electrode and the second lower electrode to the radio frequency power supply to form plasma on the surface of the second electrode, connecting the third electrode to a positive voltage, and providing a purge gas from the top to the bottom of the base by the purge device; S14: The first electrode and the second electrode are grounded or floating, and the third electrode is connected to the RF power supply to form plasma on the surface of the third electrode. The plasma formed on the surface of the third electrode is maintained for a period of time, and the purge is maintained during the period of time.

18. A plasma treatment method, characterized in that: include: S21: using a susceptor to support a substrate, generating plasma in a reaction chamber to perform plasma processing on the substrate, wherein the susceptor is disposed in the reaction chamber; S22: The susceptor includes a base, a second electrode, and a third electrode, wherein the second electrode is located on a side of the base, and the third electrode is located on a side of the second electrode away from the base, and the third electrode is insulated from the second electrode. A baffle is provided between the reaction chamber and the side of the base, and the baffle is spaced apart from the susceptor. The third electrode is located on a side of the baffle away from a supporting area of the susceptor supporting the substrate. After the plasma treatment is completed, the plasma in the reaction chamber is maintained, a voltage is applied to the second electrode to form plasma on the side of the susceptor, and a positive voltage is applied to the third electrode to enable the third electrode to absorb dust particles from the plasma formed on the side of the susceptor. S23: performing a purge from top to bottom to reduce the plasma in the reaction chamber to be closed, while maintaining the plasma on the side of the susceptor and maintaining a positive voltage on the third electrode; S24: Stop forming plasma on the side of the base, apply radio frequency voltage to the third electrode to form plasma on the surface of the third electrode, maintain the plasma on the surface of the third electrode for a period of time, and maintain the top-down purge during the period of time.

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