CN113851366B

CN113851366B - Inductively coupled plasma apparatus and method of operating the same

Info

Publication number: CN113851366B
Application number: CN202011229741.9A
Authority: CN
Inventors: 廖耕颍; 董怀仁; 林子平; 陈柏仁; 邱兆村; 吴泰进; 林玉珠; 任啟中; 周俊伟
Original assignee: Taiwan Semiconductor Manufacturing Co TSMC Ltd
Current assignee: Taiwan Semiconductor Manufacturing Co TSMC Ltd
Priority date: 2020-11-06
Filing date: 2020-11-06
Publication date: 2024-11-29
Anticipated expiration: 2040-11-06
Also published as: CN113851366A

Abstract

An inductively coupled plasma apparatus and method of operating the same includes a reaction chamber, a coil, and a wafer pedestal. The reaction chamber is provided with a body and a dielectric plate body, wherein the body and the dielectric plate body define a space, and the dielectric plate body is provided with a groove which faces the space. The coil is arranged on the surface of the dielectric plate body, which is opposite to the space. The wafer pedestal is disposed in the space.

Description

Inductively coupled plasma apparatus and method of operating the same

Technical Field

The present disclosure relates to an inductively coupled plasma apparatus and a method of operating the same.

Background

In recent years, semiconductor integrated circuits (semiconductor integrated circuits) have undergone exponential growth. With advances in integrated circuit materials and design, integrated circuits of multiple generations are produced, each generation having smaller and more complex circuits than the previous generation. As integrated circuits develop, the functional density (i.e., the number of interconnects per chip area) generally increases as the geometry (i.e., the smallest device or line that can be produced during processing) shrinks.

Generally, such a reduced-size process may provide the benefits of increased production efficiency and reduced manufacturing costs, however, such a reduced-size process may also increase the complexity of manufacturing and producing integrated circuits. To achieve these advances, corresponding developments in integrated circuit manufacturing processes and manufacturing equipment are required. In one example, a plasma etching process of a wafer is performed using a plasma manufacturing system. In a plasma etching process, a plasma generates volatile etching products by chemical reactions between elements of material etched from the wafer surface and reactive species generated by the plasma.

Disclosure of Invention

Some embodiments of the present disclosure provide an inductively coupled plasma apparatus including a reaction chamber, a coil, and a wafer pedestal. The reaction chamber is provided with a body and a dielectric plate body, wherein the body and the dielectric plate body define a space, and the dielectric plate body is provided with a groove which faces the space. The coil is arranged on the surface of the dielectric plate body, which is opposite to the space. The wafer pedestal is disposed in the space.

Some embodiments of the present disclosure provide an inductively coupled plasma apparatus including a reaction chamber, a coil, and a wafer pedestal. The reaction chamber is provided with a body and a dielectric plate body, wherein the body and the dielectric plate body define a space, the dielectric plate body comprises a first convex part, a second convex part and at least one concave part, the concave part is positioned between the first convex part and the second convex part, and the thickness of the first convex part and the thickness of the second convex part are larger than the thickness of the concave part. The coil is arranged on the surface of the dielectric plate body facing away from the space, wherein the coil is overlapped with the second convex part in the direction perpendicular to the surface of the dielectric plate body. The wafer pedestal is disposed in the space.

Some embodiments of the present disclosure provide a method of operating an inductively coupled plasma apparatus. The method includes introducing a first shielding gas into a space of a reaction chamber, wherein the reaction chamber has a body and a dielectric plate defining the space, wherein the dielectric plate has a recess facing the space, performing a first plasma process after introducing the first shielding gas into the space of the reaction chamber to form a first shielding layer on an inner surface of the reaction chamber, placing a wafer on a wafer pedestal after forming the first shielding layer, introducing a process gas into the space of the reaction chamber, performing a second plasma process on the wafer after introducing the process gas into the space of the reaction chamber, removing the wafer from the wafer pedestal, and performing a cleaning process to remove the first shielding layer.

Drawings

Aspects of the present disclosure will be understood from the following detailed description and review of the accompanying drawings. It should be noted that the various features are not drawn to scale in industry practice. In fact, the dimensions of the various features may be arbitrarily increased or reduced for clarity of discussion.

Fig. 1A is a schematic diagram of an inductively coupled plasma apparatus in accordance with some embodiments of the present disclosure;

FIG. 1B is a schematic cross-sectional view of a dielectric plate and a coil of the inductively coupled plasma apparatus of FIG. 1A;

FIG. 1C is a schematic top view of a dielectric plate of the inductively coupled plasma apparatus of FIG. 1A;

FIG. 1D is a schematic top view of a coil of the inductively coupled plasma apparatus of FIG. 1A;

FIG. 2 is a schematic cross-sectional view of a dielectric plate and coil in accordance with some embodiments of the present disclosure;

FIG. 3 is a schematic cross-sectional view of a dielectric plate and coil in accordance with some embodiments of the present disclosure;

FIG. 4A is a schematic cross-sectional view of a dielectric plate and coil in accordance with some embodiments of the present disclosure;

FIG. 4B is a schematic top view of the dielectric plate of FIG. 4A;

FIG. 4C is a schematic top view of the coil of FIG. 4A;

FIG. 5A is a schematic cross-sectional view of a dielectric plate and coil in accordance with some embodiments of the present disclosure;

FIG. 5B is a schematic top view of the dielectric plate of FIG. 5A;

FIG. 5C is a schematic top view of the coil of FIG. 5A;

fig. 6A-6D are schematic diagrams illustrating a method of operating an inductively coupled plasma apparatus in various stages according to some embodiments of the present disclosure.

[ Symbolic description ]

100 Inductively coupled plasma apparatus

110 Reaction chamber

110S closed space

112 Body

112GO gas outlet

114 Dielectric plate body

114O gas inlet port

114R groove

114D depth

114T thickness of

114A upper surface

114B lower surface

114BA part of the lower surface

114BB part of the lower surface

114BC partial lower surface

116 Plasma baffle

120 Wafer pedestal

130 Coil

130A first coil

130B second coil

140 Gas conveyer

180 Supporting seat

W is wafer

ES plasma power supply

R1 to R5 region

GS gas supply source

PG gas

FG process gas

CG gas

PL protective film

FL: byproduct film

WLA (wire bonding) wire

WLB (wire harness) wire

WL (WL: wire)

PIA input terminal

PIB input terminal

PI input terminal

POA output terminal

POB output terminal

PO output end

Detailed Description

The following disclosure provides many different implementations or examples to implement the different features of the provided patent target. Many of the elements and arrangements will be described in the following description with specific embodiments to simplify the present disclosure. These embodiments are of course intended to be examples only and should not be used to limit the disclosure. For example, the recitation "a first feature is formed on a second feature" includes various embodiments, including those in which the first feature is in direct contact with the second feature, and additional features are formed between the first feature and the second feature so that they are not in direct contact. In addition, in various embodiments, the present disclosure may repeat reference numerals and/or letters in the various examples. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed.

Furthermore, spatially relative terms, such as "lower," "below," "beneath," "upper," "above," and the like Guan Cihui, may be used herein to describe briefly a relationship of an element or feature to another element or feature as illustrated. In use or operation, these spatially relative terms encompass different orientations of the device in addition to the orientation depicted in the figures. Or the devices may be rotated (90 degrees or other angles) and spatially relative descriptors used herein interpreted accordingly.

In inductively coupled plasma apparatus, a dielectric plate is disposed between the inductive coil and the plasma, for example, at the periphery or top of the chamber. An RF current is input into the coil by using an RF source to generate an induced RF magnetic field, and then an RF electric field opposite to the RF current is induced in the cavity by the RF magnetic field. Thereby, the RF source is responsible for inductively coupling to generate plasma and control the plasma density. Quartz or ceramic material is selected as the dielectric plate body, so that the energy provided by the radio frequency source can be effectively led into electrons in the cavity.

Fig. 1A is a schematic diagram of an inductively coupled plasma apparatus 100 in accordance with some embodiments of the present disclosure. In some embodiments, the inductively coupled plasma apparatus 100 may be operable to perform a plasma etching process, such as plasma etching metal, dielectric, semiconductor, and/or masking materials (MASK MATERIALS) from the surface of the wafer W. In some embodiments, the inductively coupled plasma apparatus 100 may be operable to perform a deposition process, such as plasma depositing metal, dielectric, semiconductor, and/or masking materials on the surface of the wafer W. In some embodiments, the inductively coupled plasma apparatus 100 may be operable to perform a plasma process (e.g., plasma process metal, dielectric, semiconductor, and/or masking materials on the surface of the wafer W.

In some embodiments, the inductively coupled plasma apparatus 100 includes a reaction chamber 110, a wafer pedestal 120, a coil 130, and a gas delivery device 140. In some embodiments, the reaction chamber 110 includes a body 112 and a dielectric plate (DIELECTRIC WINDOW) 114. The body 112 and the dielectric plate 114 define a closed space 110S of the reaction chamber 110. In some embodiments, the enclosure 110S of the reaction chamber 110 is insulated from the outside environment and may be maintained in a suitable state, such as a vacuum or a pressure below atmospheric pressure.

In some embodiments, the wafer pedestal 120 is disposed in the reaction chamber 110 and is used to support the wafer W. The wafer pedestal 120 may include an electrostatic chuck electrostatic chuck and/or a clamping ring CLAMP RING (not shown) to hold the wafer W during processing. The wafer pedestal 120 may also include cooling and/or heating elements (not shown) for controlling the temperature of the wafer pedestal 120. The wafer pedestal 120 may also provide backside gas to the wafer W to increase thermal conductance between the wafer W and the wafer pedestal 120. In some embodiments, the material of the wafer base 120 may be aluminum or other suitable material, and the lift pins may penetrate through the wafer base 120 to fix the wafer W.

In some embodiments, the wafer pedestal 120 may further include an electrode coupled to a radio frequency generator (RF generator). During plasma processing, a RF generator may be applied to the electrode to provide a bias to the process gas and help energize it into a plasma. In addition, the electrode in the wafer pedestal 120 may sustain a plasma during a plasma processing process.

In some embodiments, the wafer W may be a silicon wafer. In other embodiments, the wafer W may include other elemental semiconductor materials, compound semiconductor materials, alloy semiconductor materials, or other semiconductor die, as well as other suitable substrates. For example, compound semiconductor materials include, but are not limited to, silicon carbide, gallium arsenide, gallium phosphide, indium arsenide, and/or indium antimonide. For example, alloy semiconductor materials include, but are not limited to SiGe, gaAsP, alInAs, alGaAs, gaInAs, gaInP, and/or GaInAsP.

In some embodiments, the coil 130 is disposed on the upper surface 114A of the dielectric plate 114 facing away from the enclosed space 110S. The coil 130 is electrically coupled to a plasma power source ES. The plasma power source ES is a radio frequency power source that can supply current to the coil 130 to generate radio frequency energy. The dielectric plate 114 allows the RF power provided by the plasma power source ES to be transferred from the coil 130 to the enclosure 110S of the chamber 110.

In some embodiments, the gas delivery device 140 is disposed on the dielectric plate 114. For example, the dielectric plate 114 has a gas inlet 114O connected to the gas delivery device 140. The gas delivery device 140 is coupled to a gas supply source GS and is configured to provide a process gas or other suitable gas (e.g., a cleaning gas, a shielding gas, etc.) into the enclosure 110S of the chamber 110. In various embodiments, the process gas may be an etching gas, a deposition gas, a process gas, a carrier gas CARRIER GAS (e.g., nitrogen, argon, etc.), other suitable gases, and combinations thereof. The number of gas conveyors 140 may be one or more. In some embodiments, the inlet port of the gas delivery device 140 and the gas inlet port 114O may be located approximately at the center of the coil 130. In some other embodiments, the inlet port of the gas delivery device 140 and the gas inlet port 114O may be located off-center from the coil 130.

Thus, by using the coil 130 to transfer RF energy through the dielectric plate 114 to the enclosure 110S of the chamber 110, inductively coupled plasma is formed from the process gases within the enclosure 110S of the chamber 110, thereby performing etching, deposition, and/or other plasma processes on the wafer W.

In the plasma etching process, the coils 130 are not uniformly arranged, so that the energy intensity distribution is different, and the generated plasma may have a non-uniform problem, thereby causing non-uniform etching, deposition, and/or other plasma processing of the wafer W. Furthermore, in a part of the steps, when a protective film (e.g., siCl _xO_y or a polymer) is formed on the inner surface of the closed space 110S of the reaction chamber 110 (including the sidewall of the body 112, the lower surface of the dielectric plate 114, the surface of the wafer susceptor 120, etc.), uneven plasma may cause uneven thickness of the protective film accumulated on the lower surface of the dielectric plate 114 due to the difference in energy intensity distribution. For example, current may be input from the inner ring and output from the outer ring of the coil 130, so that the lower surface of the dielectric plate 114 may accumulate thicker protective film than elsewhere in the region where the lower surface is adjacent to the inner ring of the coil 130 and its vicinity (e.g., the region between the inner ring and the outer ring). In the cleaning process, the difference in thickness of the protective film may cause film residue, which is prone to peeling off in the subsequent process to cause defects. Alternatively, the thickness of the protective film may be different during the cleaning process, which may cause the dielectric plate 114 to be damaged by the etching process of the cleaning gas.

In some embodiments of the present disclosure, the dielectric plate 114 has protruding regions R1 and R3 and recessed region R2, the regions R1 and R3 overlap the coil 130 in a vertical direction (e.g., a direction perpendicular to the upper surface 114A of the dielectric plate 114), and the region R2 does not overlap the coil 130 in the vertical direction. In other words, the dielectric plate 114 has a groove 114R, and the groove 114R and the coil 130 do not overlap in the vertical direction. In this way, the regions R1 and R3 provided with the coil 130 face the thicker dielectric plate 114, so that the energy intensity of the region can be reduced, and the region R2 not provided with the coil 130 faces the thinner dielectric plate 114, so that the energy intensity of the region can be improved. Therefore, in the plasma process, the energy intensity distribution of the regions R1-R3 is uniform, and the generated plasma is also uniform. Thus, the uniformity of etching, deposition, and/or other plasma processes of the wafer W may be improved. In addition, when the protective film is formed on the inner surface of the closed space 110S of the reaction chamber 110 by using the plasma, the protective film with a relatively uniform thickness can be obtained, and the film residue or the damage of the dielectric plate 114 caused by the cleaning process can be avoided.

In some embodiments, the dielectric plate 114 may be made of materials that are transparent to electromagnetic signals, such as quartz, ceramic, and/or dielectric materials. The electromagnetic signals may be visible light, infrared, ultraviolet, X-ray, and/or other electromagnetic signals. The electromagnetic signal passing through the dielectric plate 114 may be used to monitor the process conditions of the enclosed space 110S, such as the presence of plasma, the presence of process gas species, and/or the presence of etch/deposition residues. The dielectric plate 114 may include a suitable shape, such as a circular plate (round plate), square plate, or other suitable shape. In some embodiments, the dielectric plate 114 may be transparent. In some embodiments, the dielectric plate 114 may also be referred to as a dielectric window (DIELECTRIC WINDOW).

In some embodiments, the coil 130 may be a planar multi-turn coil (planar multi-turn coil), a non-planar multi-turn coil (non-planar multi-turn coil), or a coil having other suitable shape. In some embodiments, the coil 130 may form a plasma antenna. In other embodiments, the plasma antenna may include a plurality of plates adapted for capacitively coupling plasma (CAPACITIVELY COUPLED PLASMA). In other embodiments, the plasma may be maintained via other plasma antennas, such as electron cyclotron resonance (electron cyclotron resonance; ECR), parallel plate, spiral (helicon), spiral resonator (helical resonator), or other plasma antennas. The plasma power source ES may be, for example, a Radio Frequency (RF) power source.

In some embodiments, the inductively coupled plasma apparatus 100 may further include a support base 180 for supporting the inner and outer coils of the coil 130. The material of the support base 180 may be ceramic or other suitable material. For example, the coil 130 may be fixed under the support base 180 by suitable means (e.g. screws, not shown). In some embodiments, the support base 180 may be fixed to the dielectric plate 114 in a suitable manner, so that the relative positions of the coil 130 and the dielectric plate 114 are fixed. For example, in the present embodiment, by fixing the coil 130 and the dielectric plate 114 relative to each other by the support base 180, the coil 130 may not contact the dielectric plate 114. Alternatively, in some other embodiments, the coil 130 may contact the upper surface 114A of the dielectric plate 114 by fixing the relative positions of the coil 130 and the dielectric plate 114 of the support base 180. In some embodiments, the support base 180 may also have an opening for the gas conveyor 140 to pass through.

In some embodiments, the body 112 may comprise a plurality of elements, which may be formed of aluminum, iron, stainless steel (e.g., ferronickel), aluminum oxide, or other suitable materials. The side walls on both sides of the body 112 may be symmetrically designed to enhance plasma uniformity. In some embodiments, the body 112 may include a gas outlet 112GO, which may be coupled to a suction pump (not shown) to evacuate air from the enclosure 110S at a suitable point in time. In some embodiments, the inductively coupled plasma apparatus 100 may further include a plasma baffle 116 to define a plasma that symmetrically surrounds the wafer W. In some embodiments, the gases and byproducts can be delivered to the gas outlet 112GO via the plasma baffle 116 for evacuation. An alternative chamber material evaluation (ALTERNATE CHAMBER MATERIAL EVALUATION; ACME) film may be plated on the plasma baffle 116, wherein the film may comprise an aluminum material, such as anodized aluminum, and the film may be configured to reduce defects.

In some embodiments, the gas delivery device 140 may comprise a portion of plastic, stainless steel (e.g., ferronickel), and a material of the dielectric plate 114 (e.g., quartz or ceramic). The gas delivery device 140 may adjust the input gas velocity to improve plasma uniformity and thereby improve CD uniformity and etch uniformity.

Fig. 1B is a schematic cross-sectional view of the dielectric plate 114 and the coil 130 of the inductively coupled plasma apparatus 100 of fig. 1A. Fig. 1C is a top view of the dielectric plate 114 of fig. 1A. Fig. 1D is a schematic top view of the coil 130 of fig. 1A.

In some embodiments, the thickness of the regions R1, R3 of the dielectric plate 114 is greater than the thickness of the region R2 of the dielectric plate 114. Specifically, the dielectric plate 114 has a flat upper surface 114A and an uneven lower surface 114B, wherein the lower surface 114B is divided into partial lower surfaces 114BA, 114BB, 114BC according to the regions R1, R2, R3. In some embodiments, portions of the lower surfaces 114BA, 114BC of the regions R1, R3 of the dielectric plate 114 are lower, and portions of the lower surface 114BB of the region R2 of the dielectric plate 114 are higher. In some embodiments, portions of the lower surfaces 114BA, 114BC of the regions R1, R3 of the dielectric plate 114 may be substantially flush.

In some embodiments, the bottom surface (e.g., a portion of the lower surface 114 BB) of the recess 114R may form a proper angle with the sidewall of the recess 114R, and the sidewall of the recess 114R may form a proper angle with a portion of the lower surfaces 114BA, 114BC of the regions R1, R3. These included angles may be right angles, acute angles, or obtuse angles. As such, the cross-section of the recess 114R may be rectangular, regular trapezoid, inverted trapezoid, or other suitable shape. In the present embodiment, the cross section of the groove 114R may be rectangular, wherein in the cross section, the width of the groove 114R along the direction of the upper surface 114A may be greater than or equal to the depth 114D, or the width of the groove 114R along the direction of the upper surface 114A may be smaller than the depth 114D. In some other embodiments, the cross-section of the groove 114R may be of other suitable shapes.

In the present embodiment, the depth 114D of the recess 114R may be about 1/4 to about 1/2 times the overall thickness 114T of the dielectric plate 114. If the depth 114D of the recess 114R is less than 1/4 times the thickness 114T of the dielectric plate 114, it may be difficult to achieve the purpose of promoting plasma uniformity. If the depth 114D of the recess 114R is greater than 1/2 times the thickness 114T of the dielectric plate 114, it may be difficult to maintain the mechanical strength of the dielectric plate 114.

In some embodiments, the coil 130 includes a first coil 130A and a second coil 130B, which may be disposed around each other. At the same or different time points, the first coil 130A and the second coil 130B may apply currents in different directions and/or different magnitudes, respectively, to control distribution or other characteristics of the induction plasma, etc. In the present embodiment, the first coil 130A adopts a segmented spiral design, wherein a wire WLA is further provided to connect a plurality of unconnected segments of the first coil 130A. Similarly, the second coil 130B is of a segmented spiral design, wherein a wire WLB is also provided to connect a plurality of unconnected segments of the second coil 130B. The wires WLA and WLB may be disposed above the coil 130 without interfering with the action of the coil 130 on the underlying plasma. In some embodiments, one current may enter from the input end PIA of the coil 130A and exit from the output end POA, and another current may enter from the input end PIB of the coil 130B and exit from the output end POB, wherein the input ends PIA, PIB may be disposed in the region R1, and the output ends POA, POB may be disposed in the region R3.

In some embodiments of the present disclosure, the dielectric plate 114 may have protrusions (e.g., regions R1 and R3) corresponding to the coil 130 and recesses (e.g., region R2) not corresponding to the coil, so as to improve the uniformity of the energy provided by the coil 130 passing through the dielectric plate 114, thereby improving the uniformity of the plasma. For example, in the present embodiment, the first coil 130A and the second coil 130B are in a spiral design with separated inner and outer coils, and the inner and outer coils of the first coil 130A are connected through a wire WLA, and the wire WLB is connected to the inner and outer coils of the second coil 130B.

In the present embodiment, the inner loops of the first coil 130A and the second coil 130B are disposed on the region R1, and the outer loops of the first coil 130A and the second coil 130B are disposed on the region R3, wherein the regions R1 and R3 are separated by the groove 114R. In other words, the recess 114R of the dielectric plate 114 is disposed in a closed loop shape, so that the regions R1 and R3 are not connected. Wire WLA connects the inner ring to the outer ring of the first coil 130A across the groove 114R, and wire WLB connects the inner ring to the outer ring of the second coil 130B across the groove 114R. In other embodiments, the dielectric plate 114 may be designed according to the configuration of the coil 130, and is not limited to the one illustrated herein.

Fig. 2 is a schematic cross-sectional view of a dielectric plate and coil in accordance with some embodiments of the present disclosure. This embodiment is similar to the embodiment of fig. 1A to 1D, except that in this embodiment, the thickness of the protruding region R3 is smaller than the thickness of the protruding region R1. In other words, a portion of the lower surface 114BA of the region R1 of the dielectric plate 114 may be lower than a portion of the lower surface 114BC of the region R3 of the dielectric plate 114. This configuration makes the heights around the groove 114R different. Thus, the input ends PIA, PIB (refer to fig. 1D) face the region R1 of the thicker dielectric plate 114, and the output ends POA, POB (refer to fig. 1D) face the region R3 of the thinner dielectric plate 114, which is beneficial to improving the uniformity of the plasma. Other details of this embodiment are substantially as described above, and are not repeated here.

Fig. 3 is a schematic cross-sectional view of a dielectric plate and coil in accordance with some embodiments of the present disclosure. This embodiment is similar to the embodiment of fig. 1A-1D, except that in this embodiment, the cross-section of the groove 114R may be circular or elliptical. For example, a portion of the lower surface 114BB of the recess 114R may be semicircular or arcuate. In other embodiments, the cross-section of the groove 114R may be designed to have other suitable shapes according to the requirements. Other details of this embodiment are substantially as described above, and are not repeated here.

Fig. 4A is a schematic cross-sectional view of a dielectric plate 114 and a coil 130 according to some embodiments of the present disclosure. Fig. 4B is a top view of the dielectric plate 114 of fig. 4A. Fig. 4C is a schematic top view of the coil 130 of fig. 4A. The difference between this embodiment and the embodiment of fig. 1A to 1D is that the coil 130 is designed by taking a continuous spiral shape as an example, and the recess 114R of the dielectric plate 114 is arranged in a non-closed annular shape to match the design of the coil 130.

For example, in the present embodiment, the coil 130 continuously extends from the region R1 to the region R3. In order to match the shape of the coil 130, the convex region R1 where the inner ring of the coil 130 is located is connected to the convex region R3 where the outer ring of the coil 130 is located. In other words, the regions R1 and R3 are not separated by the groove 114R, and the recessed region R2 between the regions R1 and R3 is disposed in a non-closed annular manner. With this design, the dielectric plate 114 may have protrusions (e.g., regions R1, R3) corresponding to the coils 130 and recesses (e.g., region R2) not corresponding to the coils, so as to improve the uniformity of the energy provided by the coils 130 through the dielectric plate 114, and thus the uniformity of the plasma.

In this embodiment, a current can enter from the input terminal PI of the coil 130 and leave from the output terminal PO, wherein the input terminal PI and the output terminal PO can be disposed in the region R1. In some embodiments, the outer ring of the coil 130 may be connected to the output end PO of the inner ring through the conductive wire WL. The wire WL may be disposed above the coil 130 without interfering with the action of the coil 130 on the underlying plasma. Other details of this embodiment are substantially as described above, and will not be described here again.

Fig. 5A is a schematic cross-sectional view of a dielectric plate 114 and a coil 130 according to some embodiments of the present disclosure. Fig. 5B is a top view of the dielectric plate 114 of fig. 5A. Fig. 5C is a schematic top view of the coil 130 of fig. 5A. The present embodiment is similar to the embodiment of fig. 1A to 1D, except that in the present embodiment, the first coil 130A and the second coil 130B respectively include three separate spiral segments, such as an inner ring, a middle ring, and an outer ring, wherein the inner ring, the middle ring, and the outer ring of the first coil 130A are connected through the wire WLA, and the inner ring, the middle ring, and the outer ring of the second coil 130B are connected through the wire WLB.

In the present embodiment, the inner, middle and outer coils of the first and second coils 130A, 130B are respectively disposed in the protruding regions R1, R3, R5 of the dielectric plate 114. The dielectric plate 114 also has recessed regions R2, R4 to separate the regions R1, R3, R5. In other words, the dielectric plate 114 includes two annular grooves 114R. With this design, the dielectric plate 114 may have protrusions (e.g., regions R1, R3, R5) corresponding to the coils 130 and recesses (e.g., regions R2, R4) not corresponding to the coils, so as to improve the uniformity of the energy provided by the coils 130 through the dielectric plate 114, and thus improve the uniformity of the plasma.

In some embodiments, one current may enter from the input end PIA of the first coil 130A and exit from the output end POA, and another current may enter from the input end PIB of the second coil 130B and exit from the output end POB, wherein the input ends PIA, PIB may be disposed in the region R1, and the output ends POA, POB may be disposed in the region R5. In the present embodiment, one wire WLA connects the inner ring to the middle ring of the first coil 130A across one groove 114R, and the other wire WLA connects the middle ring to the outer ring of the first coil 130A across the other groove 114R. Similarly, one wire WLB connects the inner ring to the middle ring of the second coil 130B across one groove 114R, and the other wire WLB connects the middle ring to the outer ring of the second coil 130B across the other groove 114R. The wires WLA and WLB may be disposed above the coil 130 (see the configuration of the wire WL of fig. 4A) without interfering with the action of the coil 130 on the underlying plasma. Other details of this embodiment are substantially as described above, and will not be described here again.

Fig. 6A-6D are schematic diagrams of a method of operating an inductively coupled plasma apparatus 100 at various stages in accordance with some embodiments of the present disclosure. This description is merely exemplary and is not intended to further limit what is carried in the claims. It will be appreciated that additional steps may be added before, during and after the steps of fig. 6A-6D, and that some of the steps mentioned below may be replaced or eliminated for another part of the method embodiment. In some embodiments, the order of steps/processes may be changed.

First, referring to fig. 6A, an inductively coupled plasma apparatus 100 is provided. The inductively coupled plasma apparatus 100 includes a reaction chamber 110 (including a body 112 and a dielectric plate 114), a wafer pedestal 120, a coil 130, and a gas delivery device 140. The detailed configuration of the inductively coupled plasma apparatus 100 may be as described in any of the above embodiments, and is not described herein.

Next, referring to fig. 6B, a plasma deposition process is performed using the inductively coupled plasma apparatus 100 to deposit a protective film PL on an inner surface of the closed space 110S of the reaction chamber 110 (e.g., a lower surface of the dielectric plate 114, a sidewall of the body 112, or an upper surface of the wafer susceptor 120, etc.). For example, the gas conveyer 140 may introduce a suitable gas PG into the closed space 110S, and then control the coil 130 to perform an inductively coupled plasma process to generate plasma, thereby forming the protective film PL. In some embodiments, the gases PG may be SiCl ₄ or other suitable gases, and the material of the protective film PL may be SiCl _xO_y. In some embodiments, during the plasma deposition process, a current is supplied to the coil 130 such that the coil 130 transmits energy to the enclosed space 110S, thereby enhancing the energy of the process gas PG to generate and/or maintain the plasma. In some embodiments, the uniformity and other characteristics of the plasma may be controlled by the control coil 130 such that the plasma deposition process is substantially isotropic. In some embodiments of the present disclosure, the shape of the dielectric plate 114 is designed according to the configuration of the coil 130, and by this design, the shape of the dielectric plate 114 is beneficial to improving the uniformity of plasma, so that the thickness of the protective film PL is uniform.

In the process of plating the protective film PL, the wafer is not provided on the wafer base 120 in the sealed space 110S of the reaction chamber 110. The process of plating the protective film PL is only used to coat the inner surface of the reaction chamber 110.

Then, referring to fig. 6C, the wafer W is placed on the wafer pedestal 120 in the closed space 110S of the reaction chamber 110, and then an appropriate plasma process, such as a plasma etching process, is performed on the wafer W using the inductively coupled plasma apparatus 100. In this embodiment, the plasma etching process includes using the gas transporter 140 to transport the process gas FG into the enclosed space 110S and providing a current to the coil 130 so that the coil 130 transfers energy to the enclosed space 110S to thereby boost the energy of the process gas FG to generate and/or maintain the plasma. In some embodiments, the coil 130 and the electrode in the wafer pedestal 120 may control the uniformity and other characteristics of the plasma, such that the plasma etching process for the wafer W is anisotropic or isotropic. After the wafer W is subjected to a plasma etching process, the wafer W may be removed, and a next wafer may be placed in the closed space 110S of the reaction chamber 110, and the plasma etching process may be performed on the next wafer. In other embodiments, the plasma process performed on the wafer W may be a plasma deposition process, a plasma treatment process, or the like, without using the plasma etching Cheng Weixian.

After performing these plasma processes on a plurality of wafers W (e.g., a plurality of wafers in the same run), process byproducts may be formed on the inner surfaces of the enclosed space 110S of the reaction chamber 110 (e.g., the lower surface of the dielectric plate 114, the sidewall of the body 112, or the upper surface of the wafer pedestal 120). For example, on the protective film PL, a by-product film FL is formed.

Next, referring to fig. 6D, the wafer W is removed from the wafer pedestal 120 in the closed space 110S of the reaction chamber 110, and then a byproduct cleaning process is performed using the inductively coupled plasma apparatus 100. For example, an appropriate cleaning gas CG may be introduced into the closed space 110S, and these cleaning gases CG may be reacted with the by-product film FL and the protective film PL (refer to fig. 6D), while removing the by-product film FL and the protective film PL. These cleaning gases CG may be, for example, fluorine-containing gases or other suitable gases. In some embodiments, the byproduct film FL and the protection film PL are etched using the cleaning gas CG, and the byproduct film FL and the protection film PL are removed. In some embodiments, these gases CG may be input into the enclosed space 110S of the reaction chamber 110 by a gas conveyor 140. Alternatively, in other embodiments, the gas CG may be introduced into the enclosed space 110S of the reaction chamber 110 through other gas inlets. In some embodiments, the byproduct cleaning process is not a plasma process. In other words, the cleaning gas CG is not used to generate plasma during the byproduct cleaning process. For example, during the byproduct cleaning process, no current is provided to the coil 130. In some embodiments, the byproduct cleaning process may be substantially isotropic.

In some embodiments, after the byproduct cleaning process, the byproduct film FL and the protection film PL are removed to expose the inner surface of the reaction chamber 110, such as the lower surface of the dielectric plate 114, the sidewall of the body 112, or the upper surface of the wafer pedestal 120. In the embodiments of the present disclosure, the shape of the dielectric plate 114 is designed according to the configuration of the coil 130, and by this design, plasma uniformity can be improved, thereby improving thickness uniformity of the protective film PL. Thus, the film residue or damage of the dielectric plate 114 caused by the byproduct cleaning process can be avoided.

After the byproduct cleaning process is performed, the gas CG in the closed space 110S may be pumped out through the gas outlet 112GO (refer to fig. 1A), so as to recover the cleaning of the closed space 110S of the reaction chamber 110. At this time, the state of the inductively coupled plasma apparatus 100 is substantially the same as that of fig. 6A.

Next, the steps of fig. 6B to 6D may be performed again. For example, referring again to fig. 6B, a protective film PL is plated on an inner surface (e.g., a lower surface of the dielectric plate 114) of the closed space 110S of the reaction chamber 110. Thereafter, referring again to fig. 6C, a next wafer (e.g., a next wafer) is placed in the closed space 110S of the reaction chamber 110, and then a plasma process is performed on the next wafer (e.g., the next wafer). Next, the next wafer (e.g., the next wafer step) is removed from the enclosed space 110S of the reaction chamber 110, and a byproduct cleaning process is performed again with reference to fig. 6D to remove the protection film PL and the process byproducts.

Based on the above discussion, it can be seen that the several advantages provided by the present disclosure are presented. However, it should be understood that other embodiments may provide additional advantages, and that not all advantages need be disclosed herein, and that not all embodiments require particular advantages. One of the advantages of the present invention is to design the dielectric plate with protrusions corresponding to the coils and recesses not corresponding to the coils to promote uniformity of the plasma, and to promote uniformity of plasma etching, deposition or other processes performed on the wafer. Thus, for example, there is a higher uniformity performance in plasma etching. Another advantage of the present invention is that by designing the dielectric plate body to have a convex portion corresponding to the coil and a concave portion not corresponding to the coil, uniformity of plasma can be promoted, uniformity of deposition of the protective film on the dielectric plate body can be improved, and thus film residue or dielectric plate body damage caused by cleaning process can be avoided.

The foregoing outlines features of various embodiments, and those skilled in the art will better understand the various aspects of the present disclosure. Those skilled in the art should appreciate that the disclosure may be readily utilized as a basis for designing or modifying other processes or structures for carrying out the same purposes and/or achieving the same advantages of the embodiments presented herein. Those skilled in the art should also realize that such equivalent constructions do not depart from the spirit and scope of the disclosure, and that they may make various changes, substitutions, and alterations herein.

Claims

1. An inductively coupled plasma device, comprising:

A reaction chamber has a body and a dielectric plate, wherein the body and the dielectric plate define a space, wherein the dielectric plate has a groove, and the groove faces the space;

a coil disposed on a surface of the dielectric plate body facing away from the space, wherein the coil comprises a first coil portion and a second coil portion, the first coil portion is electrically connected to the second coil portion, and in a direction perpendicular to the surface of the dielectric plate body, the first coil portion and the second coil portion do not overlap with the groove; and

A wafer base is arranged in the space.

2. The inductively coupled plasma device according to claim 1, wherein the coil comprises a wire connecting the first coil portion to the second coil portion, and the wire overlaps the groove in the direction perpendicular to the surface of the dielectric plate.

3 . The inductively coupled plasma device according to claim 1 , wherein the groove is an annular groove.

4 . The inductively coupled plasma device according to claim 1 , wherein the dielectric plate has a gas inlet, and the groove of the dielectric plate surrounds the gas inlet.

5 . The inductively coupled plasma device according to claim 1 , wherein a depth of the groove is equal to or less than half of a thickness of the dielectric plate.

6. An inductively coupled plasma device, comprising:

A reaction chamber has a body and a dielectric plate, wherein the body and the dielectric plate define a space, the dielectric plate comprises a first convex portion, a second convex portion and at least one concave portion, the concave portion is located between the first convex portion and the second convex portion, and the thickness of the first convex portion and the second convex portion is greater than the thickness of the concave portion;

a coil disposed on a surface of the dielectric plate body facing away from the space, wherein the coil comprises a first coil portion and a second coil portion, the first coil portion is electrically connected to the second coil portion, and in a direction perpendicular to the surface of the dielectric plate body, the first coil portion overlaps with the first protrusion, the second coil portion overlaps with the second protrusion, and the first coil portion and the second coil portion do not overlap with the recess; and

A wafer base is arranged in the space.

7 . The inductively coupled plasma device according to claim 6 , wherein the surface of the dielectric plate facing away from the space is a flat surface.

8. The inductively coupled plasma apparatus according to claim 6, wherein the coil comprises a wire connecting the first coil portion to the second coil portion, and in the direction perpendicular to the surface of the dielectric plate, the wire of the coil does not overlap with the recess.

9. A method of operating an inductively coupled plasma device, comprising:

Introducing a first protective gas into a space of a reaction chamber, wherein the reaction chamber has a body and a dielectric plate, the body and the dielectric plate define the space, wherein the dielectric plate has a groove, the groove faces the space;

After the first protective gas is introduced into the space of the reaction chamber, a first plasma process is performed by providing a current to a coil to form a first protective layer on an inner surface of the reaction chamber, wherein the coil is disposed on a surface of the dielectric plate body facing away from the space, the coil comprises a first coil portion and a second coil portion, the first coil portion is electrically connected to the second coil portion, and in a direction perpendicular to the surface of the dielectric plate body, the first coil portion and the second coil portion do not overlap with the groove;

After forming the first protective layer, placing a wafer on a wafer base;

Introducing a process gas into the space of the reaction chamber;

After the process gas is introduced into the space of the reaction chamber, performing a second plasma process on the wafer;

removing the wafer from the wafer pedestal; and

A cleaning process is performed to remove the first protection layer.

10. The method according to claim 9, further comprising:

After the cleaning process is performed, introducing a second protective gas into the space of the reaction chamber; and

After the second protective gas is introduced into the space of the reaction chamber, a third plasma process is performed to form a second protective layer on the inner surface of the reaction chamber.