CN111415855B

CN111415855B - Etching apparatus

Info

Publication number: CN111415855B
Application number: CN202010268241.XA
Authority: CN
Inventors: 李嘉; 韦显旺
Original assignee: TCL Huaxing Photoelectric Technology Co Ltd
Current assignee: TCL Huaxing Photoelectric Technology Co Ltd
Priority date: 2020-04-08
Filing date: 2020-04-08
Publication date: 2022-08-23
Anticipated expiration: 2040-04-08
Also published as: CN111415855A

Abstract

The invention discloses etching equipment, which comprises a chamber, an air supply system, a lower electrode, an upper electrode and a radio frequency power supply, wherein the chamber is provided with a gas inlet and a gas outlet; wherein the upper electrode comprises an upper electrode and a fixture for holding the substrate to be processed on a lower surface of the upper electrode, the upper electrode being configured for energizing the etching gas to generate an etching plasma and inducing the etching plasma to etch the substrate to be processed positioned on the lower surface of the upper electrode; the etching equipment can realize the etching treatment of the processed substrate kept on the upper electrode, thereby avoiding the bad products caused by the falling of particles or corresponding solid products on the processed substrate.

Description

Etching equipment

Technical Field

The invention relates to the technical field of display, in particular to etching equipment.

Background

In the field of semiconductor display manufacturing, dry etching is a common etching process. Dry etching is a process in which a specific etching gas is introduced into a reaction chamber, and an etching plasma is generated by a Radio Frequency (RF) electric field to etch a workpiece to be etched.

There are four main modes of dry etching commonly used in the field of semiconductor display, namely PE mode, RIE mode, ICP mode and ECCP mode. FIGS. 1A-1D are schematic diagrams of PE mode, RIE mode, ICP mode, and ECCP mode, respectively.

As shown in fig. 1A to 1D, in the four common etching modes of the dry etching, the substrate 2 to be processed is placed on the lower electrode 1, so that the particles or the corresponding solid products inevitably fall onto the substrate, thereby causing poor product.

Disclosure of Invention

The present invention is directed to solve the above problems, and an object of the present invention is to provide an etching apparatus, which can maintain a substrate to be processed on an upper electrode by configuring the upper electrode with a radio frequency power supply and a fixing device, so as to prevent particles or corresponding solid products from falling down on the substrate to be processed, which may result in poor product.

In order to solve the problems, the etching equipment adopts the following technical scheme.

The invention provides an etching device, which is used for etching a processed substrate and comprises: a chamber for accommodating a substrate to be processed and performing an etching process on the substrate; a gas supply system for supplying an etching gas for performing an etching process into the chamber; a lower electrode disposed within the chamber; an upper electrode disposed within the chamber and including an upper electrode and a fixture; wherein the fixing device is used for positioning the processed substrate on the lower surface of the upper electrode, and the upper electrode is configured for converting the etching gas into etching plasma and inducing the etching plasma to perform etching processing on the lower surface of the processed substrate.

Further, the etching apparatus further comprises a radio frequency power supply, the radio frequency power supply comprising: the source radio frequency power supply is connected with the upper electrode and is used for providing source radio frequency power to the upper electrode; and a bias RF power source connected to the upper electrode for providing bias RF power to the bias electrode.

Further, the lower electrode includes a lower electrode, and the lower electrode is grounded.

Further, the upper electrode includes a gas hole extending through a thickness thereof, the gas hole being configured to inject a heat exchange gas toward the substrate being processed.

Further, an electrostatic chuck is disposed inside the upper electrode, and the electrostatic chuck is used for performing electrostatic adsorption on the processed substrate.

Further, the upper electrode is also provided with a heat exchange channel, and the heat exchange channel is communicated with a heat exchange medium source and is used for keeping the temperature of the upper electrode within a certain range.

Further, the gas supply system includes a plurality of gas jets, the gas jets are located the upper portion electrode with between the lower part electrode in the cavity, be used in the gas jet system with the fluid communication of cavity.

Further, the air nozzles are symmetrically arranged along the circumferential direction of the inner side wall of the chamber.

Further, the etching apparatus also includes an exhaust system configured to be fluidly connected to the chamber for exhausting at least gas within the chamber.

Further, the exhaust system comprises a molecular pump and a pump line pipeline, wherein the molecular pump is in fluid connection with the chamber, and the pump line pipeline is in fluid connection with the molecular pump.

Furthermore, a guide plate is arranged in the cavity and used for uniformly distributing the etching gas supplied to the cavity by the gas supply system on the lower surface of the upper electrode.

The etching equipment has the following beneficial effects:

(1) according to the etching equipment, the upper electrode is provided with the radio frequency power supply and the fixing device, so that the etching treatment of the treated substrate kept on the upper electrode can be realized, and the phenomenon that particles or corresponding solid products fall down on the treated substrate to cause poor products can be avoided;

(2) the upper electrode is provided with the air holes and the heat exchange pipeline, so that the temperature of the upper electrode can be regulated and controlled, and the etching uniformity of the processed substrate is improved;

(3) through with the air jet along the cavity inside wall circumference symmetry sets up, can realize evenly spraying etching gas, can also prevent to cause the air jet to block up the problem because of reaction product falls.

Drawings

The technical solution and other advantages of the present invention will become apparent from the following detailed description of specific embodiments of the present invention, which is to be read in connection with the accompanying drawings.

Fig. 1A to 1D are schematic diagrams of a PE mode, an RIE mode, an ICP mode, and an ECCP mode, respectively, of dry etching.

FIG. 2 is a schematic structural diagram of an etching apparatus according to the present invention.

FIG. 3 is a top view of the etching apparatus of the present invention.

Detailed Description

The technical solution in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. It should be apparent that the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments, which can be obtained by a person skilled in the art without inventive step based on the embodiments of the present invention, are within the scope of protection of the present invention.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", and the like, indicate orientations and positional relationships based on those shown in the drawings, and are used only for convenience of description and simplicity of description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be considered as limiting the present invention. Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or to implicitly indicate the number of technical features indicated. Thus, features defined as "first", "second", may explicitly or implicitly include one or more of the described features. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; may be mechanically connected, may be electrically connected or may be in communication with each other; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the present invention, unless otherwise expressly stated or limited, "above" or "below" a first feature means that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact with each other via another feature therebetween. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.

The following disclosure provides many different embodiments or examples for implementing different features of the invention. To simplify the disclosure of the present invention, the components and arrangements of specific examples are described below. Of course, they are merely examples and are not intended to limit the present invention. Furthermore, the present invention may repeat reference numerals and/or letters in the various examples, such 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. In addition, the present invention provides examples of various specific processes and materials, but one of ordinary skill in the art will recognize the application of other processes and/or the use of other materials.

As shown in fig. 2, the present invention provides an etching apparatus comprising a chamber 10, a gas supply system 20 (not shown), a lower electrode 30, an upper electrode 40, and a radio frequency power source 50. The upper electrode 40 includes an upper electrode 41 and a fixing device 42. The fixing device 42 is used for positioning the substrate 70 to be processed on the lower surface of the upper electrode 41, and the upper electrode 41 is configured to excite the etching gas supplied by the gas supply system 20 into the inner cavity 10 to generate an etching plasma and induce the etching plasma to perform an etching process on the substrate 70 to be processed held below the upper electrode 41.

Therefore, the etching apparatus of the present invention can fix the substrate 70 to be processed on the upper electrode 40 and perform the etching process on the substrate 70, so as to avoid the problem that the substrate 70 to be processed is not good due to the particles or the solid products falling onto the substrate 70 when the substrate 70 to be processed is fixed on the lower electrode 30.

The etching apparatus of the present invention can realize the effect of holding the substrate 70 to be processed on the lower surface of the upper electrode 30 and performing the etching process on the lower surface of the substrate 70 to be processed by configuring the upper electrode 40 with the rf power source 50 and the fixing device 42, and can solve the problem that the particles or the corresponding solid products fall onto the substrate 70 to be processed when the substrate 50 to be processed is fixed on the lower electrode 30.

As shown in fig. 2, the chamber 10 is used for receiving a substrate 40 to be processed and performing an etching process on the substrate 40 to be processed.

With continued reference to fig. 2, in the present embodiment, the chamber 10 is a hollow cavity having opposing top and bottom portions and a sidewall between the top and bottom portions. In specific implementation, the upper electrode 20 and the lower electrode 30 are respectively located at the top and the bottom of the cavity and are oppositely arranged.

As shown in fig. 2, the gas supply system 20 is configured to be in fluid connection with the chamber 10 for supplying an etching gas for performing an etching process to the inside of the chamber 10.

As shown in fig. 2, the gas supply system 20 includes a plurality of gas nozzles 21 and communicates with the inner chamber 10 through the gas nozzles 21. That is, the gas supply system 20 supplies the etching gas to the chamber 10 through the gas ejection port 21.

The gas orifice 21 is positioned within the chamber 10 between the upper electrode 40 and the lower electrode 30. And, the gas nozzles 21 are symmetrically arranged along the circumferential direction of the inner sidewall of the chamber 10.

Specifically, the etching gas is selected from one or more of argon, helium, xenon, nitrogen, and hydrogen.

As shown in fig. 2, a lower electrode 30 and an upper electrode 40 are disposed in the chamber 10, wherein the upper electrode 40 is configured to excite the etching gas supplied by the gas supply system 20 into the inner chamber 10 to generate an etching plasma and induce the etching plasma to perform an etching process on the substrate 70 to be processed, which is held under the upper electrode 41.

Specifically, the rf electric field established between the upper electrode 40 and the lower electrode 30 excites the etching gas to turn into an etching plasma and guides charged ions (e.g., argon ions Ar +) of the etching plasma to the upper electrode 40, which bombards the processed substrate 70 held on the upper electrode 40 by the holding device 42.

As shown in fig. 2, the upper electrode 40 is disposed in the chamber 10 and includes an upper electrode 41 and a fixing device 42, wherein the upper electrode 41 is disposed opposite to the lower electrode 30, and the fixing device 42 is used for holding the processed substrate 70 on the lower surface of the upper electrode 41.

With continued reference to fig. 2, in the present embodiment, the upper electrode 41 is fixed on the top of the chamber 10 through the upper surface thereof. The fixing device 42 is installed at the top of the chamber 10, and the fixing device 42 is positioned at the periphery of the upper electrode 41 so as to hold the substrate 70 to be processed on the lower surface of the upper electrode 41. That is, the surface of the substrate 70 to be processed faces the lower electrode 30.

Specifically, the upper electrode 41 is formed with an air hole 411 (not shown) extending through the thickness thereof. That is, the air holes 411 can penetrate through the opposite upper and lower surfaces of the upper electrode 41.

The gas holes 411 are configured to inject a heat exchange gas toward the substrate 70 to be processed, and the substrate 70 to be processed can be cooled by the heat exchange gas. In one embodiment, the air vent 411 is configured to communicate with a source of heat exchange gas. The heat exchange gas source can provide the heat exchange gas, and the heat exchange gas is sprayed on the processed substrate 70 through the gas holes 411.

In specific implementation, the heat exchange gas may be nitrogen.

Specifically, the lower surface of the upper electrode 41 has a certain roughness. By keeping the lower surface of the upper electrode 41 at a certain roughness, the heat exchange gas sprayed to the substrate 70 through the gas holes 411 can be filled between the substrate 70 and the lower surface of the upper electrode 41, so that the heat exchange gas can uniformly cool the substrate 70, and the substrate 70 is prevented from having a large temperature difference at various positions, thereby affecting the etching uniformity.

In particular implementations, at least the lower surface of the upper electrode 41 can be roughened by sandblasting, bead blasting, arc blasting, plasma blasting, or other roughening process.

Specifically, an electrostatic chuck (ESC)412 (not shown) is disposed in the upper electrode 41. Wherein the electrostatic chuck 412 can have a single or multi-polar chucking electrode and provide chucking force by coulombic effect or Johnsen-Rahbek effect. In one implementation, the diameter of the electrostatic chuck 412 can be larger than the diameter of the substrate 70 to achieve better chucking.

Further, the upper electrode 41 is further configured with a heat exchange channel 413, and the heat exchange channel 413 is configured to be communicated with a heat exchange medium source and is used for controlling the temperature of the upper electrode 41 within a certain range.

By supplying a heat exchange medium into the heat exchange channel 413 and controlling the heat exchange medium to circulate in the heat exchange channel 413, the heat generated by the gas impacting the upper electrode 41 can be reduced, thereby ensuring good etching uniformity and high etching speed of the processed substrate 70 and ensuring better product processing quality.

In this embodiment, the heat exchange channel 413 is formed inside the upper electrode 41, and the heat exchange channel 413 has a winding structure and is arranged along the extending direction of the upper electrode 41.

In other embodiments, the heat exchanging channel 413 can be formed on other sides of the upper electrode 41.

In specific implementation, the upper electrode 41 is further provided with a plurality of temperature detection elements and a temperature controller, and the temperature detection elements are arranged on the upper electrode 41 in an array and used for detecting the temperature of each part of the upper electrode 41. The temperature controller is electrically connected with the temperature detection piece and the heat exchange medium source. Therefore, the temperature of the upper electrode 41 is detected in real time through the temperature detection piece, the on-off supply of the heat exchange medium source can be flexibly controlled through the temperature controller, the reliable work of the upper electrode 41 is ensured, and the good etching uniformity of the product is ensured; in addition, the method is also beneficial to reducing equipment loss and resource consumption and improving the production economy of enterprises.

In this embodiment, the heat exchange medium source may be a cooling liquid tank or a cooling liquid tank.

As shown in fig. 2, the lower electrode 30 is located at the bottom of the chamber 10 and is disposed opposite to the upper electrode 20.

In the present embodiment, the lower electrode 30 is a plate electrode. In a specific implementation, the lower electrode 30 is configured to be disposed at the bottom of the chamber 10 by supporting a lower surface thereof.

The upper electrode 40 is disposed at the top of the chamber 10, and the lower surface of the upper electrode 40 is disposed opposite to the upper surface of the lower electrode 30.

As shown in fig. 2, the etching apparatus 100 further includes a Radio Frequency (RF) power source 50 for supplying RF power to the upper electrode 41 or the upper electrode 40.

As shown in fig. 2, the rf power source 50 includes a source rf power source 51 and a bias rf power source 52 electrically connected to the upper electrode 41, respectively. Wherein the source rf power supply 51 provides source rf power to the upper electrode 41 configured to form an rf electric field for converting an etching gas into an etching plasma.

The bias rf power supply 52 provides bias power to the upper electrode 41 to configure the upper electrode 41 to be biased relative to the lower electrode for directing the bombardment direction of the etching plasma.

Specifically, the lower electrode 30 is grounded. In one embodiment, the lower electrode 30 is connected to the chamber 10 and grounded through the chamber 10.

As shown in fig. 2, the etching apparatus 100 further comprises an exhaust system 60, wherein the exhaust system 60 is configured to be in fluid connection with the chamber 10 at least for exhausting the gas in the chamber 10. The exhaust system 60 can be used to set the pressure in the chamber 10 to a predetermined pressure.

In a specific embodiment, the supply of the etching gas from the upper electrode 20 and the exhaust of the gas from the exhaust system 60 are continued during the entire etching process, and the pressure in the chamber 10 can be maintained within a predetermined pressure range by the cooperation and cooperation of these operations

Specifically, the exhaust system 60 is disposed at the bottom of the chamber 10.

As shown in fig. 2, the exhaust system 60 includes a molecular pump 61 and a pump line 62, the molecular pump 61 is fluidly connected to the chamber 10, and the pump line 62 is fluidly connected to the molecular pump 61.

In this embodiment, the Molecular Pump 61 is a TMP (Turbo Molecular Pump). As shown in fig. 3, a baffle 80 is also disposed within the chamber 10. The baffle 80 is disposed at the bottom of the chamber 10 for reflecting or directing the etching gas of the gas ejection port 21 toward the upper electrode 41.

In the foregoing embodiments, the descriptions of the respective embodiments have respective emphasis, and for parts that are not described in detail in a certain embodiment, reference may be made to the related descriptions of other embodiments.

The above detailed description is provided for an etching apparatus provided in the embodiments of the present invention, and the principle and the implementation of the present invention are explained by applying specific examples, and the above description of the embodiments is only used to help understanding the technical solution and the core idea of the present invention; those of ordinary skill in the art will understand that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.

Claims

1. An etching apparatus for performing an etching process on a substrate to be processed, comprising:

a chamber for receiving a substrate to be processed to perform an etching process on the substrate;

a gas supply system for supplying an etching gas for performing an etching process into the chamber;

a lower electrode disposed within the chamber;

an upper electrode disposed within the chamber and including an upper electrode and a fixture; wherein the content of the first and second substances,

the upper electrode comprises a gas hole extending through the thickness of the upper electrode, the gas hole is configured to spray heat exchange gas to the processed substrate, and the lower surface of the upper electrode has a preset roughness; the upper electrode is also provided with a heat exchange channel, and the heat exchange channel is communicated with a heat exchange medium source and is used for keeping the temperature of the upper electrode within a preset range;

the fixing device is used for positioning the processed substrate on the lower surface of the upper electrode, and the upper electrode is configured for converting the etching gas into etching plasma and inducing the etching plasma to perform etching processing on the lower surface of the processed substrate.

2. The etching apparatus of claim 1, further comprising an rf power source, the rf power source comprising:

the source radio frequency power supply is connected with the upper electrode and is used for providing source radio frequency power to the upper electrode; and the number of the first and second groups,

a bias RF power source connected to the top electrode for providing bias RF power to the top electrode.

3. The etching apparatus of claim 1, wherein the lower electrode comprises a lower electrode, and the lower electrode is grounded.

4. The etching apparatus according to claim 1, wherein an electrostatic chuck for electrostatically attracting the substrate to be processed is provided inside the upper electrode.

5. The etching apparatus of claim 1, wherein the gas supply system includes a plurality of gas injection ports located in the chamber between the upper electrode and the lower electrode for fluid communication of the gas supply system and the chamber.

6. The etching apparatus of claim 5, wherein the gas orifices are symmetrically arranged along a circumference of an inner sidewall of the chamber.

7. The etching apparatus of claim 1, further comprising an exhaust system configured to be fluidly connected to the chamber for exhausting at least gas within the chamber.

8. The etching apparatus of claim 7, wherein the exhaust system comprises a molecular pump fluidly connected to the chamber and a pump line fluidly connected to the molecular pump.

9. The etching apparatus of claim 1, further comprising a baffle plate disposed within the chamber for uniformly distributing the etching gas supplied to the chamber by the gas supply system over a lower surface of the upper electrode.