Electrostatic chuck device, dry etching equipment and dry etching method

Abstract

The present invention provides an electrostatic chuck device, dry etching equipment and dry etching method. The electrostatic chuck device comprises a base, a dielectric layer, an electrode circuit and a power supply circuit. The electrode circuit comprises a plurality of independent positive electrodes and negative electrodes. The plurality of positive electrodes and the plurality of negative electrodes are staggered and dispersed and insulated from each other. The power supply circuit comprises a positive power supply sub-circuit connected to the positive electrode and a negative power supply sub-circuit connected to the negative electrode. The power supply circuit has a switching selection function and can realize switching control between single-electrode adsorption and double-electrode adsorption. Based on the switching selection of the power supply circuit in the electrostatic chuck device, the semiconductor substrate can be adsorbed. At the same time, based on the Coulomb attraction between the positive electrode of the electrostatic chuck device and the negative charge of plasma in the dry etching equipment, the non-conductor substrate can be adsorbed, thereby realizing compatible adsorption of the semiconductor substrate and the non-conductor substrate and improving the utilization efficiency of the machine.

Description

Technical Field

[0001] The invention belongs to the field of semiconductor manufacturing, and in particular relates to an electrostatic chuck device, dry etching equipment and a dry etching method. Background Art

[0002] During dry etching, the substrate needs to be fixed at the bottom of the etching chamber. Generally, an electrostatic chuck (ESC) is used to adsorb and fix the substrate. At the same time, in current dry etching equipment, the electrostatic chuck also serves as a lower electrode.

[0003] However, in some semiconductor manufacturing fields such as the LED industry, not all substrates (substrates) used are made of semiconductor materials. Taking red light as an example, gallium arsenide (GaAs) may be used as a substrate, or sapphire may be used as a substrate. The currently designed electrostatic chucks are all used for a single function. They can adsorb semiconductors but not non-conductive materials such as sapphire or glass. Therefore, when it is necessary to use both semiconductor substrates and non-conductive substrates for multi-route and multi-product development, one machine (electrostatic chuck or dry etching equipment) cannot simultaneously meet the adsorption and etching of semiconductor substrates and non-conductive substrates. New machines must be purchased to meet the development process conditions, which is costly and has low utilization efficiency of each machine. Summary of the invention

[0004] In view of the above-mentioned shortcomings of the prior art, an object of the present invention is to provide a technical solution of an electrostatic chuck that can be used for adsorption and fixation of semiconductor substrates and non-conductor substrates at the same time, so as to solve the above-mentioned technical problems.

[0005] To achieve the above-mentioned purpose and other related purposes, the specific technical solutions provided by the present invention are as follows.

[0006] An electrostatic chuck device, characterized in that it comprises:

[0007] Pedestal;

[0008] a dielectric layer disposed on the base; and

[0009] An electrode circuit, comprising a positive electrode subcircuit and a negative electrode subcircuit, wherein the positive electrode subcircuit comprises a plurality of independent positive electrodes, and the negative electrode subcircuit comprises a plurality of independent negative electrodes, and each of the positive electrodes and each of the negative electrodes are dispersed in the dielectric layer;

[0010] The electrostatic chuck device realizes single-electrode adsorption or double-electrode adsorption by switching on and off the positive electrode sub-circuit and / or the negative electrode sub-circuit.

[0011] In the above-mentioned electrostatic suction cup device, the adsorption mode of single electrode adsorption and double electrode adsorption can be freely switched. Both adsorption modes can adsorb semiconductor substrates. At the same time, the mutual attraction between the positive electrode and the negative charge of the plasma in the dry etching equipment can effectively adsorb non-conductive substrates, thereby realizing compatible adsorption of semiconductor substrates and non-conductive substrates, and improving the utilization efficiency of the machine; in addition, multiple positive electrodes and multiple negative electrodes are dispersedly arranged in the dielectric layer, so that the adsorption force distribution of the electrostatic suction cup device is relatively dispersed and uniform, and the overall adsorption effect is good.

[0012] Optionally, at least part of the positive electrodes and at least part of the negative electrodes are interlaced and insulated from each other and dispersed in the dielectric layer. A plurality of positive electrodes and a plurality of negative electrodes are interlaced and dispersedly arranged in the dielectric layer, so that the overall distribution of the adsorption force of the electrostatic chuck device is relatively uniform, and the overall adsorption effect is better.

[0013] Optionally, it also includes:

[0014] A power supply circuit, the power supply circuit includes a positive power supply sub-circuit and a negative power supply sub-circuit, the positive power supply sub-circuit is electrically connected to the positive electrode sub-circuit, and the negative power supply sub-circuit is electrically connected to the negative electrode sub-circuit.

[0015] Optionally, the positive power supply sub-circuit includes a first switch, and the negative power supply sub-circuit includes a second switch; the electrostatic suction cup device realizes single-electrode adsorption or double-electrode adsorption by turning on and off the positive electrode sub-circuit and / or the negative electrode sub-circuit, and realizes single-electrode adsorption or double-electrode adsorption by turning on and off the first switch and / or the second switch.

[0016] Optionally, the electrostatic chuck device is provided in a dry etching device;

[0017] The positive power supply electronic circuit further includes a positive power supply, a negative end of the positive power supply is grounded, a positive end of the positive power supply is connected to each of the positive electrodes, one end of the first switch is connected to the side wall of the etching chamber of the dry etching device, and the other end of the first switch is grounded;

[0018] The negative power supply subcircuit further includes a negative power supply, a negative end of the negative power supply is connected to each of the negative electrodes, and a positive end of the negative power supply is grounded after being connected in series with the second switch.

[0019] Optionally, the positive power supply subcircuit further includes a third switch, and the negative end of the positive power supply is grounded after being connected in series with the third switch.

[0020] Optionally, the electrostatic chuck device is provided in a dry etching device;

[0021] The positive power supply electronic circuit further includes a positive power supply, a negative end of the positive power supply is grounded, a positive end of the positive power supply is connected to each of the positive electrodes, one end of the first switch is connected to the side wall of the etching chamber of the dry etching device, and the other end of the first switch is grounded;

[0022] The negative power supply electronic circuit further includes a negative power supply, the negative end of the negative power supply is connected to each of the negative electrodes through the second switch connected in series, and the positive end of the negative power supply is grounded.

[0023] Optionally, the positive power supply subcircuit further includes a third switch, and the positive end of the positive power supply is connected to each of the positive electrodes through the third switch connected in series.

[0024] Optionally, the positive electrode comprises a disc-shaped electrode, and the negative electrode comprises a disc-shaped electrode; a plurality of the positive electrodes are distributed in a dispersed point shape, and a plurality of the negative electrodes are distributed in a dispersed point shape.

[0025] A dry etching device, the dry etching device at least comprises an etching chamber, an upper electrode, an etching gas supply unit and an electrostatic chuck device as described in any one of the above items, wherein the electrostatic chuck device is arranged at the bottom of the etching chamber, and the electrostatic chuck device is arranged opposite to the upper electrode.

[0026] In the above-mentioned dry etching equipment, the switching of the adsorption modes between single-electrode adsorption and double-electrode adsorption based on the electrostatic chuck device can achieve compatible adsorption of semiconductor substrates and non-conductor substrates, thereby improving the utilization efficiency and application scope of the machine; multiple positive electrodes and multiple negative electrodes are dispersedly arranged in the dielectric layer, and the adsorption force distribution of the electrostatic chuck device is relatively dispersed and uniform, which has a good overall effect on substrate adsorption and is convenient for subsequent etching.

[0027] A dry etching method, comprising:

[0028] Providing the above-mentioned dry etching equipment;

[0029] placing a substrate on the electrostatic chuck device;

[0030] Controlling the electrostatic chuck device to switch on and off the positive electrode subcircuit and / or the negative electrode subcircuit according to the material of the substrate to adsorb the substrate;

[0031] Introducing etching gas into the etching chamber and applying power to the upper electrode of the dry etching device to generate plasma; and

[0032] The substrate is dry-etched using the plasma.

[0033] In the above-mentioned dry etching method, based on the switching of the adsorption mode of the electrostatic chuck device, compatible adsorption of semiconductor substrates and non-conductor substrates can be achieved, which is convenient for subsequent etching, improves the etching application range of the machine, and improves the etching efficiency; based on the structural design in which the positive electrode and the negative electrode are dispersedly arranged in the dielectric layer, the adsorption force of the electrostatic chuck device on the substrate is relatively dispersed and uniform, and the overall effect of substrate adsorption is good, which can effectively avoid the phenomenon of sliding and falling off of the substrate during etching, which affects the etching effect.

[0034] Optionally, the substrate comprises a semiconductor substrate, and the step of controlling the electrostatic chuck device to switch on and off the positive electrode subcircuit and / or the negative electrode subcircuit according to the material of the substrate to adsorb the substrate comprises:

[0035] The positive electrode sub-circuit and the negative electrode sub-circuit are turned on simultaneously to polarize the semiconductor substrate, and the polarized semiconductor substrate is adsorbed on the surface of the electrostatic chuck device.

[0036] Optionally, the substrate comprises a semiconductor substrate, and the step of controlling the electrostatic chuck device to switch on and off the positive electrode subcircuit and / or the negative electrode subcircuit according to the material of the substrate to adsorb the substrate comprises:

[0037] Turning on the positive electrode sub-circuit and disconnecting the negative electrode sub-circuit to polarize the semiconductor substrate;

[0038] The side wall of the etching chamber is grounded so that the semiconductor substrate acquires negative charge from the plasma; the polarized semiconductor substrate that acquires negative charge is adsorbed on the surface of the electrostatic chuck device.

[0039] Optionally, the substrate includes a non-conductive substrate, and the step of controlling the electrostatic chuck device to switch on and off the positive electrode sub-circuit and / or the negative electrode sub-circuit according to the material of the substrate to adsorb the substrate includes:

[0040] Turning on the positive electrode sub-circuit and disconnecting the negative electrode sub-circuit;

[0041] The side wall of the etching chamber is grounded so that the non-conductive substrate acquires negative charges from the plasma; the non-conductive substrate acquiring negative charges is adsorbed on the surface of the electrostatic chuck device. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 FIG. 4 is a schematic diagram of the structure of an electrostatic chuck device in one embodiment of the present invention.

[0043] Figure 2 - Figure 4 for Figure 1 A partial perspective view of the electrostatic chuck device.

[0044] Figure 5 - Figure 8 Schematic diagram of the structure of the distribution of positive and negative electrodes of the electrostatic chuck device in other embodiments of the present invention.

[0045] Fig. 9 for Figure 1 Schematic diagram of the electrostatic chuck device with positive and negative dual electrodes adsorbing the semiconductor substrate.

[0046] Fig.10 for Figure 1 Schematic diagram of a single positive electrode of an electrostatic chuck device adsorbing a non-conductive substrate.

[0047] Fig.11 for Figure 1 Schematic diagram of a single positive electrode of an electrostatic chuck device adsorbing a semiconductor substrate.

[0048] Fig.12 FIG. 4 is a schematic diagram of the structure of an electrostatic chuck device in another embodiment of the present invention.

[0049] Fig.13 FIG. 4 is a schematic diagram of the structure of an electrostatic chuck device in another embodiment of the present invention.

[0050] Description of Figure Numbers

[0051] 1—base, 2—dielectric layer, 3—electrode circuit, 31—positive electrode sub-circuit, 32—negative electrode sub-circuit, 311—positive electrode, 312—first electrode line, 321—negative electrode, 322—second electrode line, 4—etching cavity sidewall, 5—semiconductor substrate, 6—non-conductor substrate, VCC—positive power supply, VEE—negative power supply, GND—ground, K1—first switch, K2—second switch, K3—third switch. DETAILED DESCRIPTION

[0052] As described in the above background technology, the inventors have found that in some multi-route and multi-product development situations, semiconductor substrates and non-conductive substrates need to be used simultaneously for product experiments and development, but the current dry etching equipment and electrostatic chucks are specially designed, and the electrostatic chucks that can adsorb semiconductor substrates cannot adsorb non-conductive substrates. To conduct experimental development of non-conductive substrates, new machines must be purchased to meet the development process conditions, which will undoubtedly increase the experimental development costs.

[0053] Based on this, the present invention proposes a technical solution for an electrostatic chuck: both positive and negative electrodes are arranged inside the electrostatic chuck, and positive electricity is provided to the positive electrode and negative electricity is provided to the negative electrode through an external power supply circuit, and the on-off state of the positive and negative electricity is controllable, thereby realizing the switching control of single-electrode adsorption and double-electrode adsorption, and utilizing the negative charge of the plasma in the dry etching equipment and the positive electrode of the electrostatic chuck to adsorb non-conductive materials, thereby realizing compatible adsorption of semiconductor substrates and non-conductive substrates; at the same time, the positive electrode and the negative electrode are divided into a plurality of independently dispersed small electrodes, and the plurality of small positive electrodes and the plurality of small negative electrodes are staggered and dispersed and then insulated, so that the adsorption force of the electrostatic chuck is evenly distributed, thereby improving the overall adsorption effect.

[0054] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0055] See also Figures 1 to 13 . It should be noted that the illustrations provided in this embodiment only illustrate the basic concept of the present invention in a schematic manner, so the illustrations only show the components related to the present invention rather than being drawn according to the number, shape and size of the components in actual implementation. The type, quantity and proportion of each component in actual implementation can be changed arbitrarily, and the component layout type may also be more complex. The structure, proportion, size, etc. illustrated in the illustrations attached to this specification are only used to match the content disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions for the implementation of the present invention. Therefore, it has no technical substantive significance. Any modification of the structure, change in the proportional relationship or adjustment of the size should still fall within the scope of the technical content disclosed by the present invention without affecting the effect that the present invention can produce and the purpose that can be achieved.

[0056] like Figure 1 As shown, an embodiment of the present invention provides an electrostatic chuck device, which includes:

[0057] Base 1;

[0058] A dielectric layer 2 is disposed on the base 1;

[0059] The electrode circuit 3 includes a positive electrode subcircuit 31 and a negative electrode subcircuit 32, wherein the positive electrode subcircuit 31 includes a plurality of independent positive electrodes 311, and the negative electrode subcircuit 32 includes a plurality of independent negative electrodes 321, and each positive electrode 311 and each negative electrode 321 are dispersed in the dielectric layer 2;

[0060] The electrostatic chuck device realizes single-electrode adsorption or double-electrode adsorption by switching on and off the positive electrode sub-circuit 31 and / or the negative electrode sub-circuit 32 .

[0061] In detail, Figure 1 As shown, the base 1 mainly plays a supporting role and auxiliary cooling role. For example, it is made of metals such as aluminum, titanium alloys or metal alloys such as stainless steel materials, which is conducive to the input of radio frequency energy. The base 1 can also be made of a composite of ceramics and metals with high strength, good durability and good thermal conductivity, which is convenient for heat dissipation of the substrate during subsequent dry etching.

[0062] In detail, Figure 1 As shown, the dielectric layer 2 is arranged on the base 1. The dielectric layer 2 can be a pure dielectric material (insulator), and the corresponding electrostatic chuck is a Coulomb force type electrostatic chuck, which mainly relies on the Coulomb force between opposite charges for adsorption. The adsorption and desorption speeds are fast, but the adsorption force is small, and a higher voltage needs to be applied to the electrode; the dielectric layer 2 can also be a doped dielectric material (conductor or semiconductor), and the corresponding electrostatic chuck is a Jungian heat back type electrostatic chuck. When a voltage is applied to the electrode, the charge on the electrode can move and concentrate on the upper surface of the dielectric layer 2, so that the distance between the opposite charges is close, and the adsorption force (Coulomb force) is increased, but the charge movement takes time, and the adsorption and desorption speeds are slow.

[0063] In an optional embodiment of the present invention, the material of the dielectric layer 2 is a heat-resistant ceramic material, and the ceramic material can be a single ceramic formed by one of aluminum nitride (AlN), aluminum oxide (Al2O3), silicon nitride (Si3N4), zirconium oxide (ZrO2), Sialon, boron nitride (BN), and silicon carbide (SiC), or a composite ceramic composed of two or more of them.

[0064] In an optional embodiment of the present invention, the dielectric layer 2 is made of a heat-resistant ceramic material, and the ceramic material is ion-doped to conduct mobile charges.

[0065] In more detail, a cooling liquid pipeline is provided in the base 1, and a cooling gas pipeline is provided in the base 1 and the dielectric layer 2. The cooling gas pipeline is mainly used for the circulation of heat-conducting gas such as helium to dissipate heat from the substrate during subsequent dry etching. The cooling liquid pipeline and the cooling gas pipeline are arranged opposite to each other, and are mainly used to cool the heat-conducting gas and transfer the heat to the outside of the electrostatic suction cup device and even to the outside of the entire dry etching equipment; wherein, the cooling gas pipeline in the dielectric layer 2 is mainly a plurality of pores passing through the dielectric layer 2. The specific structure can refer to the prior art and will not be repeated here.

[0066] In detail, Figure 1As shown, the electrode circuit 3 is embedded in the dielectric layer 2, and includes a positive electrode sub-circuit 31 and a negative electrode sub-circuit 32. The positive electrode sub-circuit 31 includes a plurality of independent positive electrodes 311 and a first electrode line 312, and each positive electrode 311 is electrically connected to the first electrode line 312, respectively. The negative electrode sub-circuit 32 includes a plurality of independent negative electrodes 321 and a second electrode line 322, and each negative electrode 321 is electrically connected to the second electrode line 322, respectively. Among them, the material of the positive electrode 311 and the negative electrode 321 can be a high melting point metal or metal alloy material, such as molybdenum, tungsten and compounds thereof. In more detail, the base 1 has an upper surface and a lower surface that are arranged opposite to each other, and viewed in a vertical direction along the upper surface of the base 1, a plurality of positive electrodes 311 and a plurality of negative electrodes 321 are interlaced and dispersedly arranged in the dielectric layer 2 in an insulated manner, as shown in FIG. Figure 1 and Figure 2 The plurality of positive electrodes 311 and the plurality of negative electrodes 321 are interlaced and dispersedly arranged in the dielectric layer 2, so that the overall distribution of the adsorption force of the electrostatic chuck device is relatively uniform, and the overall adsorption effect is better.

[0067] In an optional embodiment of the present invention, Figure 2 As shown, the positive electrode 311 is in the shape of a disc, and the negative electrode 321 is also in the shape of a disc; Figure 3 As shown, the plurality of positive electrodes 311 are distributed in a dispersed point shape, and the first electrode lines 312 are distributed in a grid shape; Figure 4 As shown, the plurality of negative electrodes 321 are distributed in a dispersed point shape, and the second electrode lines 322 are distributed in a grid shape; the plurality of positive electrodes 311 and the plurality of negative electrodes 321 are interlaced and insulated from each other.

[0068] In an optional embodiment of the present invention, Figure 5 As shown, two positive electrodes 311 in the shape of a disc are a positive electrode dispersion unit, and two negative electrodes 321 in the shape of a disc are a negative electrode dispersion unit. Multiple positive electrode dispersion units and multiple negative electrode dispersion units are staggered and insulated from each other. The first electrode line 312 and the second electrode line 322 are still distributed in a grid shape, with a slight change in shape, which will not be repeated here.

[0069] In an optional embodiment of the present invention, Figure 6 As shown, three disk-shaped positive electrodes 311 constitute a positive electrode dispersion unit, and three disk-shaped negative electrodes 321 constitute a negative electrode dispersion unit. The plurality of positive electrode dispersion units and the plurality of negative electrode dispersion units are interlaced and insulated from each other.

[0070] In an optional embodiment of the present invention, Figure 7As shown, four disk-shaped positive electrodes 311 constitute a positive electrode dispersion unit, and four disk-shaped negative electrodes 321 constitute a negative electrode dispersion unit. The plurality of positive electrode dispersion units and the plurality of negative electrode dispersion units are interlaced and insulated from each other.

[0071] In an optional embodiment of the present invention, Figure 8 As shown, the positive electrode 311 and the negative electrode 321 are both square, with a single positive electrode 311 or a single negative electrode 321 as a dispersed unit, and multiple positive electrodes 311 and multiple negative electrodes 321 are staggered and dispersed and insulated from each other.

[0072] It should be noted that the specific shape and staggered dispersion form of the positive electrode 311 and the negative electrode 321 are not limited to the above description, as long as "the entire positive electrode and the negative electrode are dispersed into multiple independent small blocks, and the block-shaped small positive electrodes and the block-shaped small negative electrodes are staggered and dispersed and insulated from each other, so that the entire positive electrode and the entire negative electrode are evenly dispersed in the dielectric layer 2 and the entire positive electrode and the entire negative electrode are cross-distributed".

[0073] In detail, Figure 1 As shown, the electrostatic suction cup device also includes a power supply circuit, which includes a positive power supply sub-circuit and a negative power supply sub-circuit. The positive power supply sub-circuit is electrically connected to multiple positive electrodes 311 through a first electrode line 312, and the negative power supply sub-circuit is electrically connected to multiple negative electrodes 321 through a second electrode line 322, that is, the positive power supply sub-circuit is electrically connected to the positive electrode sub-circuit 31, and the negative power supply sub-circuit is electrically connected to the negative electrode sub-circuit 32.

[0074] Among them, the power supply circuit has a switching selection function to switch and select the on and off states of the positive power supply sub-circuit and the negative power supply sub-circuit, thereby realizing the on and off operation of the positive electrode sub-circuit 31 and / or the negative electrode sub-circuit 32, and further realizing the switching control of the single-electrode adsorption and double-electrode adsorption of the electrostatic suction cup device.

[0075] In more detail, Figure 1 As shown, the entire electrostatic chuck device is arranged in the dry etching equipment, generally placed at the bottom of the etching chamber of the dry etching equipment, and the power supply circuit includes a positive power supply sub-circuit and a negative power supply sub-circuit; the positive power supply sub-circuit includes a positive power supply VCC and a first switch K1, the negative end of the positive power supply VCC is grounded GND, the positive end of the positive power supply VCC is connected to each positive electrode 311 through a first electrode line 312, one end of the first switch K1 is connected to the side wall 4 of the etching chamber of the dry etching equipment, and the other end of the first switch K1 is grounded GND; the negative power supply sub-circuit includes a negative power supply VEE and a second switch K2, the negative end of the negative power supply VEE is connected to each negative electrode 321 through a second electrode line 322, and the positive end of the negative power supply VEE is connected to the ground GND after being connected in series with the second switch K2.

[0076] In detail, Figure 1 As shown, the power supply circuit has a switching selection function, the positive power supply sub-circuit is turned on by default, that is, the positive electrode sub-circuit 31 is turned on by default, and the on-off state of the negative power supply sub-circuit is switched and selected by the second switch K2, that is, the on-off state of the negative electrode sub-circuit 32 is switched and selected by the second switch K2: when the second switch K2 is disconnected, the negative electrode sub-circuit 32 is disconnected, the positive electrode sub-circuit 31 is turned on, and the electrostatic chuck device is in a single positive electrode adsorption mode; when the second switch K2 is closed, the negative electrode sub-circuit 32 and the positive electrode sub-circuit 31 are both turned on, and the electrostatic chuck device is in a dual electrode adsorption mode. The first switch K1 controls whether the side wall 4 of the etching chamber is grounded GND, and is used to form an electric field between the positive electrode 311 to attract negative charges in the plasma when the single positive electrode is adsorbed.

[0077] Therefore, the electrostatic chuck device realizes single-electrode adsorption or double-electrode adsorption by turning on and off the positive electrode subcircuit 31 and / or the negative electrode subcircuit 32. In essence, the electrostatic chuck device realizes single-electrode adsorption or double-electrode adsorption by turning on and off the first switch K1 and / or the second switch K2. In more detail, Figure 9-11 As shown, Figure 1 The electrostatic chuck device shown is arranged in a dry etching device, and its adsorption principle is as follows.

[0078] When the substrate placed on the electrostatic chuck device is a semiconductor substrate, such as Fig. 9 As shown, the second switch K2 is closed, the positive electrode sub-circuit 31 and the negative electrode sub-circuit 32 are both turned on, the positive electrode 311 is connected to the positive power supply VCC, and the negative electrode 321 is connected to the negative power supply VEE. Positive charges are distributed on the positive electrode 311, and negative charges are distributed on the negative electrode 321. Under the influence of the charge electric field of the positive electrode 311 and the negative electrode 321, the interior of the semiconductor substrate 5 is polarized, and negative charges are gathered near the positive electrode 311, and positive charges are gathered near the negative electrode 321. The gathered charges generated by the polarization inside the semiconductor substrate 5 generate Coulomb attraction with the positive electrode 311 and the negative electrode 321 respectively, so that the polarized semiconductor substrate 5 is adsorbed on the surface of the electrostatic suction cup device. At this time, the electrostatic suction cup device can be in the positive and negative dual electrode adsorption mode.

[0079] When the substrate placed on the electrostatic chuck device is a non-conductive substrate, such as Fig.10As shown, the first switch K1 is closed and the second switch K2 is disconnected, the positive electrode sub-circuit 31 is turned on, the negative electrode sub-circuit 32 is disconnected, the positive electrode 311 is connected to the positive power supply VCC, and the etching chamber side wall 4 of the dry etching device is grounded GND. At the same time, etching gas is introduced into the etching chamber, and the upper electrode of the dry etching device is energized to generate plasma in the etching chamber. Positive charges are distributed on the positive electrode 311. Under the influence of the electric field formed between the positive electrode 311 and the etching chamber side wall 4, the electrons (negative charges) in the plasma are quickly injected into the non-conductor substrate 6 and approach the positive electrode 311. The negative charges obtained by the non-conductor substrate 6 from the plasma and the positive charges distributed on the positive electrode 311 generate Coulomb attraction, so that the non-conductor substrate 6 is adsorbed on the surface of the electrostatic suction cup device. At this time, the electrostatic suction cup device can be in a single positive electrode adsorption mode.

[0080] It is understandable that the above-mentioned single positive electrode adsorption mode can also be used for adsorption of semiconductor substrates. When the substrate placed on the electrostatic chuck device is a semiconductor substrate, such as Fig.11 As shown, the first switch K1 is closed and the second switch K2 is disconnected, the positive electrode sub-circuit 31 is turned on, the negative electrode sub-circuit 32 is disconnected, the positive electrode 311 is connected to the positive power supply VCC, and the etching chamber side wall 4 of the dry etching device is grounded GND. At the same time, etching gas is introduced into the etching chamber, and the upper electrode of the dry etching device is energized to generate plasma in the etching chamber. Positive charges are distributed on the positive electrode 311. Under the influence of the electric field formed between the positive electrode 311 and the etching chamber side wall 4, the electrons (negative charges) in the plasma are quickly injected into the interior of the semiconductor substrate 5 and approach the positive electrode 311. Under the influence of the positive charge electric field of the positive electrode 311, the interior of the semiconductor substrate 5 is polarized, and some negative charges gather on the side close to the positive electrode 311. The negative charges obtained by the semiconductor substrate 5 from the plasma and some negative charges generated by its internal polarization generate Coulomb attraction with the positive charges distributed on the positive electrode 311, so that the semiconductor substrate 5 is adsorbed on the surface of the electrostatic chuck device.

[0081] In this way, based on the switching selection of the single positive electrode adsorption mode and the double electrode adsorption mode of the electrostatic chuck device, it can be used for the adsorption of both semiconductor substrates and non-conductive substrates, realizing the compatible adsorption of semiconductor substrates and non-conductive substrates and improving the utilization efficiency of the machine; in addition, multiple positive electrodes and multiple negative electrodes are staggered and dispersed and then insulated from each other, and the positive electrodes and negative electrodes are evenly dispersed in the dielectric layer. The adsorption force distribution of the entire electrostatic chuck device is relatively uniform, which can avoid the phenomenon of weak overall adsorption force, easy loosening or poor heat dissipation due to the large adsorption force in the local area or the small adsorption force in the local area, and the overall adsorption effect and heat dissipation effect are better.

[0082] In an optional embodiment of the present invention, Fig.12As shown, the positive power supply sub-circuit further includes a third switch K3, the negative end of the positive power supply VCC is connected to the ground via the third switch K3 connected in series, and the on-off state of the positive power supply sub-circuit is switched and selected by the third switch K3, that is, the on-off state of the positive electrode sub-circuit 31 is switched and selected by the third switch K3: when the second switch K2 is closed and the third switch K3 is opened, the negative electrode sub-circuit 32 is turned on and the positive electrode sub-circuit 31 is turned off, and the electrostatic chuck device is in a single negative electrode adsorption mode (the Coulomb attraction is small and generally not considered); when the second switch K2 is opened and the third switch K3 is closed, the negative electrode sub-circuit 32 is turned off and the positive electrode sub-circuit 31 is turned on, and the electrostatic chuck device is in a single positive electrode adsorption mode (at this time , the first switch K1 is closed accordingly to enhance the attraction to negative charges in the plasma); when the second switch K2 is closed and the third switch K3 is closed, the negative electrode sub-circuit 32 is turned on and the positive electrode sub-circuit 31 is turned on, and the electrostatic suction cup device is in the positive and negative dual electrode adsorption mode; when the second switch K2 is disconnected and the third switch K3 is disconnected, the negative electrode sub-circuit 32 is disconnected and the positive electrode sub-circuit 31 is disconnected, and the electrostatic suction cup device cannot be electrostatically adsorbed; by controlling the second switch K2 and the third switch K3, and coordinating the first switch K1 with the third switch K3, the switching control of the single electrode adsorption and the dual electrode adsorption of the electrostatic suction cup device can be realized, and the specific adsorption principle can be referred to the above description, which will not be repeated here.

[0083] It should be noted that the positions of the first switch K1 in the negative power supply subcircuit and the third switch K3 in the positive power supply subcircuit can be slightly changed, as long as "the first switch K1 controls the on-off state of the negative power supply subcircuit and the negative electrode subcircuit 32, and the third switch K3 controls the on-off state of the positive power supply subcircuit and the positive electrode subcircuit 31". In another optional embodiment of the present invention, Fig.13 As shown, the entire electrostatic chuck device is arranged at the bottom of the etching chamber of the dry etching equipment, the positive power supply circuit includes a positive power supply VCC, a first switch K1 and a third switch K3, the negative end of the positive power supply VCC is grounded GND, the positive end of the positive power supply VCC is connected to each positive electrode 311 after passing through the third switch K3 connected in series (through the first electrode line 312), one end of the first switch K1 is connected to the side wall 4 of the etching chamber of the dry etching equipment, and the other end of the first switch K1 is grounded GND; the negative power supply circuit includes a negative power supply VEE and a second switch K2, the negative end of the negative power supply VEE is connected to each negative electrode 321 after passing through the second switch K2 connected in series (through the second electrode line 322), and the positive end of the negative power supply VEE is grounded GND.

[0084] Among them, Fig.13The electrostatic chuck device shown can realize the switching control of single-electrode adsorption and double-electrode adsorption of the electrostatic chuck device through the control of the second switch K2 and the third switch K3, and the coordinated control of the first switch K1 and the third switch K3. The specific adsorption principle can be analyzed with reference to the above description and will not be repeated here.

[0085] In the above-mentioned electrostatic suction cup device, the adsorption mode of single electrode adsorption and double electrode adsorption can be freely switched. Both adsorption modes can adsorb semiconductor substrates. At the same time, based on the mutual attraction between the positive electrode 311 and the negative charge of the plasma in the dry etching equipment, the non-conductive substrate can be effectively adsorbed, thereby realizing the compatible adsorption of the semiconductor substrate and the non-conductive substrate, and improving the utilization efficiency of the machine; in addition, multiple positive electrodes 311 and multiple negative electrodes 321 are dispersedly arranged in the dielectric layer 2, so that the adsorption force distribution of the electrostatic suction cup device is relatively dispersed and uniform, and the overall adsorption effect is good.

[0086] At the same time, the present invention also provides a dry etching device, which at least includes an etching chamber, an upper electrode, an etching gas providing unit and the above-mentioned electrostatic suction cup device. The electrostatic suction cup device is arranged at the bottom of the etching chamber, and the electrostatic suction cup device is arranged opposite to the upper electrode. Based on the structural design of the above-mentioned electrostatic suction cup device, compatible adsorption of semiconductor substrates and non-conductor substrates can be achieved, thereby improving the utilization efficiency of the machine.

[0087] In the above-mentioned dry etching equipment, the switching of the adsorption mode between single-electrode adsorption and double-electrode adsorption based on the electrostatic suction cup device can realize compatible adsorption of semiconductor substrates and non-conductive substrates, thereby improving the utilization efficiency and application scope of the machine; multiple positive electrodes 311 and multiple negative electrodes 321 are dispersedly arranged in the dielectric layer 2, and the adsorption force distribution of the electrostatic suction cup device is relatively dispersed and uniform, and the overall effect of substrate adsorption is good, which is convenient for subsequent etching.

[0088] In addition, based on the adsorption principle of the electrostatic chuck device, the present invention also provides a dry etching method, which is applied to dry etching of a substrate in a dry etching device, and comprises the steps of:

[0089] S1. Provide the above-mentioned dry etching equipment;

[0090] S2, placing a substrate on the electrostatic chuck device;

[0091] S3, controlling the electrostatic chuck device to switch on and off the positive electrode sub-circuit 31 and / or the negative electrode sub-circuit 32 according to the material of the substrate to adsorb the substrate;

[0092] S4, introducing etching gas into the etching chamber, and energizing the upper electrode of the dry etching device to generate plasma; and

[0093] S5. Dry-etching the substrate using plasma.

[0094] Optionally, in step S2, the substrate includes a semiconductor substrate, and for the semiconductor substrate, the step S2 of controlling the electrostatic suction cup device to switch on and off the positive electrode sub-circuit 31 and / or the negative electrode sub-circuit 32 according to the material of the substrate to adsorb the substrate further includes: simultaneously turning on the positive electrode sub-circuit 31 and the negative electrode sub-circuit 32 to polarize the semiconductor substrate, and the polarized semiconductor substrate is adsorbed on the surface of the electrostatic suction cup device.

[0095] Optionally, in step S2, for a semiconductor substrate, controlling the electrostatic chuck device to switch on and off the positive electrode subcircuit 31 and / or the negative electrode subcircuit 32 according to the material of the substrate to adsorb the substrate may further include:

[0096] S21, turning on the positive electrode sub-circuit 31 and turning off the negative electrode sub-circuit 32 to polarize the semiconductor substrate;

[0097] S22, grounding the side wall of the etching chamber to GND so that the semiconductor substrate acquires negative charge from the plasma; the polarized semiconductor substrate that acquires negative charge is adsorbed on the surface of the electrostatic chuck device.

[0098] Optionally, in step S2, the substrate includes a non-conductive substrate, and for the non-conductive substrate, the step S2 of controlling the electrostatic chuck device to switch on and off the positive electrode sub-circuit 31 and / or the negative electrode sub-circuit 32 according to the material of the substrate to adsorb the substrate further includes:

[0099] S2a, turning on the positive electrode sub-circuit 31 and turning off the negative electrode sub-circuit 32;

[0100] S2b, grounding the side wall of the etching chamber to GND so that the non-conductive substrate acquires negative charges from the plasma; the non-conductive substrate with negative charges is adsorbed on the surface of the electrostatic chuck device.

[0101] In the above-mentioned dry etching method, based on the switching of the adsorption mode of the electrostatic suction cup device, compatible adsorption of semiconductor substrates and non-conductive substrates can be achieved, which is convenient for adsorption and fastening during subsequent etching, thereby increasing the applicable range of etching of the machine and improving the etching efficiency; based on the structural design in which the positive electrode 311 and the negative electrode 321 are dispersedly arranged in the dielectric layer 2, the adsorption force of the electrostatic suction cup device on the substrate is relatively dispersed and uniform, and the overall effect of adsorption on the substrate is good, which can effectively avoid the phenomenon of sliding and falling off of the substrate during etching, which affects the etching effect.

[0102] In addition, it should be noted that the above description of the electrostatic suction cup device omits the detailed structure description of the cooling gas pipeline and the cooling liquid pipeline, and the above description of the dry etching equipment omits the structures such as the etching gas shower head, which are well known to the general technicians in this field and will not be described in detail here.

[0103] In summary, the electrostatic chuck device, dry etching equipment and dry etching method provided by the present invention can adsorb semiconductor substrates through two adsorption modes of single-electrode adsorption and double-electrode adsorption of the electrostatic chuck device based on the switching selection of the power supply circuit in the electrostatic chuck device. At the same time, the Coulomb attraction between the positive electrode of the electrostatic chuck device and the negative charge of the plasma in the dry etching equipment can effectively adsorb non-conductor substrates, thereby realizing compatible adsorption of semiconductor substrates and non-conductor substrates and improving the utilization efficiency of the machine. In addition, multiple positive electrodes and multiple negative electrodes are staggered and dispersed and then insulated from each other, and the positive electrodes and negative electrodes are evenly and dispersedly arranged in the dielectric layer. The adsorption force distribution of the entire electrostatic chuck device during electrostatic adsorption is relatively uniform, which can avoid the phenomenon of weak overall adsorption force, easy loosening and falling off, or poor heat dissipation due to the large adsorption force in the local area or the small adsorption force in the local area. The overall adsorption effect and heat dissipation effect are better, which effectively improves the etching efficiency and etching quality during subsequent etching.

[0104] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. An electrostatic chuck device, characterized in that: Applied to dry etching equipment, the dry etching equipment includes an etching chamber, the electrostatic chuck device is arranged at the bottom of the etching chamber, and the electrostatic chuck device includes: Pedestal; a dielectric layer disposed on the base; and An electrode circuit, comprising a positive electrode subcircuit and a negative electrode subcircuit, wherein the positive electrode subcircuit comprises a plurality of independent positive electrodes, and the negative electrode subcircuit comprises a plurality of independent negative electrodes, and each of the positive electrodes and each of the negative electrodes are dispersed in the dielectric layer; Wherein, when the substrate placed on the dielectric layer is a semiconductor substrate, the positive electrode subcircuit and the negative electrode subcircuit are both turned on to achieve dual-electrode adsorption; When the substrate placed on the dielectric layer is a non-conductive substrate, plasma is generated in the etching chamber, the positive electrode subcircuit is turned on and the negative electrode subcircuit is turned off to achieve single electrode adsorption.

2. The electrostatic chuck device according to claim 1, characterized in that: At least part of the positive electrodes and at least part of the negative electrodes are interlaced with each other and dispersed in the dielectric layer in an insulated manner.

3. The electrostatic chuck device according to claim 1, characterized in that: Also includes: A power supply circuit, the power supply circuit includes a positive power supply sub-circuit and a negative power supply sub-circuit, the positive power supply sub-circuit is electrically connected to the positive electrode sub-circuit, and the negative power supply sub-circuit is electrically connected to the negative electrode sub-circuit.

4. The electrostatic chuck device according to claim 3, characterized in that: The positive power supply subcircuit includes a first switch, and the negative power supply subcircuit includes a second switch; Wherein, when the substrate placed on the dielectric layer is a semiconductor substrate, both the first switch and the second switch are turned on to achieve dual-electrode adsorption; When the substrate placed on the dielectric layer is a non-conductive substrate, plasma is generated in the etching chamber, the first switch is turned on and the second switch is turned off to achieve single electrode adsorption.

5. The electrostatic chuck device according to claim 4, characterized in that: The positive power supply subcircuit further comprises a positive power supply, a negative end of the positive power supply is grounded, a positive end of the positive power supply is connected to each of the positive electrodes, one end of the first switch is connected to the side wall of the etching chamber of the dry etching device, and the other end of the first switch is grounded; The negative power supply subcircuit further includes a negative power supply, a negative end of the negative power supply is connected to each of the negative electrodes, and a positive end of the negative power supply is grounded after being connected in series with the second switch.

6. The electrostatic chuck device according to claim 5, characterized in that: The positive power supply subcircuit further includes a third switch, and the negative end of the positive power supply is connected in series with the third switch and then grounded.

7. The electrostatic chuck device according to claim 4, characterized in that: The positive power supply subcircuit further comprises a positive power supply, a negative end of the positive power supply is grounded, a positive end of the positive power supply is connected to each of the positive electrodes, one end of the first switch is connected to the side wall of the etching chamber of the dry etching device, and the other end of the first switch is grounded; The negative power supply electronic circuit further includes a negative power supply, the negative end of the negative power supply is connected to each of the negative electrodes through the second switch connected in series, and the positive end of the negative power supply is grounded.

8. The electrostatic chuck device according to claim 7, characterized in that: The positive power supply subcircuit further includes a third switch, and the positive end of the positive power supply is connected to each of the positive electrodes through the third switch connected in series.

9. The electrostatic chuck device according to any one of claims 1 to 8, characterized in that: The positive electrode comprises a disc-shaped electrode, and the negative electrode comprises a disc-shaped electrode; a plurality of the positive electrodes are distributed in a dispersed point shape, and a plurality of the negative electrodes are distributed in a dispersed point shape.

10. A dry etching device, characterized in that: The dry etching equipment at least comprises an etching chamber, an upper electrode, an etching gas supply unit and an electrostatic chuck device according to any one of claims 1 to 9, wherein the electrostatic chuck device is arranged at the bottom of the etching chamber and is arranged opposite to the upper electrode.

11. A dry etching method, characterized in that: include: Providing a dry etching apparatus as claimed in claim 10; placing a substrate on the electrostatic chuck device; Controlling the electrostatic chuck device to switch on and off the positive electrode subcircuit and / or the negative electrode subcircuit according to the material of the substrate to adsorb the substrate; Introducing etching gas into the etching chamber and applying power to the upper electrode of the dry etching device to generate plasma; as well as The substrate is dry-etched using the plasma.

12. The dry etching method according to claim 11, characterized in that: The substrate includes a semiconductor substrate, and the step of controlling the electrostatic chuck device to switch on and off the positive electrode subcircuit and / or the negative electrode subcircuit according to the material of the substrate to adsorb the substrate includes: The positive electrode sub-circuit and the negative electrode sub-circuit are turned on simultaneously to polarize the semiconductor substrate, and the polarized semiconductor substrate is adsorbed on the surface of the electrostatic chuck device.

13. The dry etching method according to claim 11, characterized in that: The substrate includes a semiconductor substrate, and the step of controlling the electrostatic chuck device to switch on and off the positive electrode subcircuit and / or the negative electrode subcircuit according to the material of the substrate to adsorb the substrate includes: Turning on the positive electrode sub-circuit and disconnecting the negative electrode sub-circuit to polarize the semiconductor substrate; The side wall of the etching chamber is grounded so that the semiconductor substrate acquires negative charge from the plasma; the polarized semiconductor substrate that acquires negative charge is adsorbed on the surface of the electrostatic chuck device.

14. The dry etching method according to claim 11, characterized in that: The substrate includes a non-conductive substrate, and the step of controlling the electrostatic chuck device to switch on and off the positive electrode sub-circuit and / or the negative electrode sub-circuit according to the material of the substrate to adsorb the substrate includes: Turning on the positive electrode sub-circuit and disconnecting the negative electrode sub-circuit; The side wall of the etching chamber is grounded so that the non-conductive substrate acquires negative charges from the plasma; the non-conductive substrate acquiring negative charges is adsorbed on the surface of the electrostatic chuck device.

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