CN117612920B

CN117612920B - Reactive gas switching system and plasma processing apparatus

Info

Publication number: CN117612920B
Application number: CN202410089019.1A
Authority: CN
Inventors: 向浪; 王兆祥; 梁洁; 李可; 涂乐义
Original assignee: Shanghai Bangxin Semiconductor Technology Co ltd
Current assignee: Shanghai Bangxin Semiconductor Technology Co ltd
Priority date: 2024-01-23
Filing date: 2024-01-23
Publication date: 2024-04-05
Anticipated expiration: 2044-01-23
Also published as: CN117612920A

Abstract

The present disclosure relates to the field of plasma processing, and provides a reactive gas switching system and a plasma processing apparatus, the system comprising: a first pressure controller; a second pressure controller; first valves and second valves include respectively: an intake valve and an exhaust valve configured to be opened/closed in opposite states; the control unit is used for setting states of the first air inlet valve and the second air inlet valve, and setting ventilation duration of the first air inlet valve and preset pressure parameters of the first pressure controller to reach corresponding first preset flow; and the ventilation duration of the second air inlet valve and the preset pressure parameter of the second pressure controller are set to reach the corresponding second preset flow. A common section of the first transmission pipeline and the second transmission pipeline, which is communicated with the reaction cavity, is provided with a flow restrictor; a reaction cavity is provided with a pressure gauge; the pumping speed between the air pump and the cavity pressure pump is controlled to be unchanged, the pipeline state is kept to enable the valve group to be switched, the opening of the restrictor is adjusted to enable the reading of the pressure gauge to be stable, and the resistance of the public section is the same as that of the exhaust channel. The pressure control cooperates with the exhaust and restrictor to avoid fluctuations.

Description

Reactive gas switching system and plasma processing apparatus

Technical Field

The present disclosure relates to the technical field of plasma processing apparatuses, and in particular, to a reactive gas switching system and a plasma processing apparatus.

Background

In the etching process of the plasma processing apparatus, the etching (etc) and Deposition (DEP) operations of the through silicon via are required to be alternately switched to ensure that the through silicon via has a good aspect ratio and other process requirements, so that two paths of gases are required to be used in the etching process and are mutually switched to achieve the target process effect.

Generally, etching systems typically use a gas Mass Flow Controller (MFC) to control the feed and shut-off of two process gases to a reaction CHAMBER (reactor). Thus, some defects are generated.

Firstly, when the MFC controls the flow, the corresponding valve is closed to cause the closed air-holding of the pipeline connected with the reaction cavity, so that the pressure in the pipeline is increased. When the valve is opened again, high-pressure gas between the valve and the reaction chamber is fed into the reaction chamber, so that the original pressure and flow rate of a pipeline behind the MFC can be changed due to other gas path elements, the flow is uncontrollable, and the chamber pressure is influenced.

Second, MFCs have a slow response speed (typically <300 milliseconds) to two-way gas control and switching, since it is necessary to switch the two gases frequently. Moreover, the MFC is usually installed at the gas source (e.g., a gas holder) and is far away from the reaction chamber, which may cause a situation that the MFC continues to supply gas even after the MFC is completely closed, again reducing the control accuracy. Thus, the resulting actual full handoff may be significantly longer than the 300 ms described above, and the delay time may be up to 2 seconds.

Disclosure of Invention

In view of the above-described drawbacks of the related art, an object of the present disclosure is to provide a reactive gas switching system and a plasma processing apparatus, which solve the problems in the related art.

A first aspect of the present disclosure provides a reactant gas switching system for switching at least a first reactant gas or a second reactant gas suitable for different operation types into a reaction chamber of a semiconductor processing apparatus; the reactive gas switching system includes: a first pressure controller communicated in a first transfer line for delivering a first reactant gas; the second pressure controller is communicated in a second transmission pipeline for conveying a second reaction gas; a first valve block comprising: the first air inlet valve is communicated with the first transmission pipeline to a first air inlet pipeline of the reaction cavity; the first exhaust valve is communicated with the first exhaust pipeline from the first transmission pipeline to the exhaust channel; wherein the first intake valve and the first exhaust valve are configured to be opened/closed in opposite states; a second valve block comprising: the second air inlet valve is communicated with the second transmission pipeline to a second air inlet pipeline of the reaction cavity; a common section communicated with the reaction cavity is arranged between the first air inlet pipeline and the second air inlet pipeline, and a restrictor for increasing the pipeline resistance to be the same as the resistance at the position of the exhaust channel is arranged in the common section; the exhaust channel is communicated with the air extracting pump, and the reaction cavity is communicated with the cavity pressure pump; the reaction cavity is provided with a pressure gauge; the pumping speed between the pumping pump and the cavity pressure pump is controlled to be unchanged through a control unit, and the valve opening of a gas path and a valve opening of an exhaust channel between the reaction cavity and a first reaction gas source and a second reaction gas source are kept unchanged, so that a first valve group or a second valve group is switched to adjust the opening of the flow restrictor according to pressure fluctuation displayed by the pressure gauge until the reading of the pressure gauge is stable; the second exhaust valve is communicated in a second exhaust pipeline from the second transmission pipeline to the exhaust channel; wherein the second intake valve and the second exhaust valve are configured to be opened/closed in opposite states; the control unit is used for setting the opening/closing states of the first air inlet valve, the first air outlet valve, the second air inlet valve and the second air outlet valve, and reaching a first preset flow of the corresponding first reaction gas by setting the ventilation duration of the first air inlet valve and the preset pressure parameter of the first pressure controller; and the ventilation time length of the second air inlet valve and the preset pressure parameter of the second pressure controller are set to reach the second preset flow of the corresponding second reaction gas.

In an embodiment of the first aspect, the first intake valve and the second intake valve are disposed in opposite open/close states; and/or, the reactive gas switching system comprises: the control unit is used for setting valve states of the first valve group and the second valve group and setting preset pressure parameters of the first pressure controller and the second pressure controller; and/or the first air inlet valve, the first air outlet valve, the second air inlet valve and the second air outlet valve are atomic layer deposition diaphragm valves; and/or the first and second reactant gases are adapted to reactant gases for semiconductor etching and deposition, respectively.

In an embodiment of the first aspect, the exhaust channel is communicated with an air extracting pump, and the reaction cavity is communicated with a cavity pressure pump; the reaction cavity is provided with a pressure gauge; the pumping speed between the pumping pump and the cavity pressure pump is controlled to be unchanged through a control unit, and the valve opening of the gas path and the valve opening of the exhaust channel between the reaction cavity and the first reaction gas source and the second reaction gas source are kept unchanged, so that the first valve group or the second valve group is switched to be in a state, and the opening of the flow restrictor is adjusted according to pressure fluctuation displayed by the pressure gauge until the reading of the pressure gauge is stable.

In an embodiment of the first aspect, a first set of mass flow controllers is in communication between the first reactant gas source and the first pressure controller; the first set of mass flow controllers includes a plurality of first mass flow controllers; each first mass flow controller is used for controlling one path of first reaction gas, and the output pipelines of the first mass flow controllers are connected so as to mix multiple paths of first reaction gases and output the mixed gases to the first pressure controller; a second set of mass flow controllers in communication between a second reactant gas source and a second pressure controller; the second set of mass flow controllers includes a plurality of second mass flow controllers; each second mass flow controller is used for controlling one path of second reaction gas, and the output pipelines of the second mass flow controllers are connected to output the mixed multiple paths of second reaction gas to the second pressure controller.

In an embodiment of the first aspect, the first intake valve and the first exhaust valve are one and the other of a normally open valve and a normally closed valve, respectively; the first air inlet valve and the first air outlet valve are controlled by a first control flow passage supplied by the first pilot valve module to switch the open/close state, and a first electromagnetic valve which is coupled with and controlled by the control unit is arranged in the first control flow passage.

In an embodiment of the first aspect, the first intake valve is a normally closed valve and the first exhaust valve is a normally open valve.

In an embodiment of the first aspect, the second intake valve and the second exhaust valve are one and the other of a normally open valve and a normally closed valve, respectively; the second air inlet valve and the second air outlet valve are controlled by a second control flow passage supplied by a second pilot valve module to switch the open/close state, and a second electromagnetic valve which is coupled with and controlled by the control unit is arranged in the second control flow passage.

In an embodiment of the first aspect, the second intake valve is a normally closed valve and the second exhaust valve is a normally open valve.

A second aspect of the present disclosure provides a plasma processing apparatus, comprising: the reactive gas switching system according to any one of the first aspects.

As described above, the embodiments of the present disclosure provide a reactive gas switching system and a plasma processing apparatus, the reactive gas switching system including: a first pressure controller communicated in a first transfer line for delivering a first reactant gas; the second pressure controller is communicated in a second transmission pipeline for conveying a second reaction gas; a first valve block comprising: a first intake valve and a first exhaust valve; the first intake valve and the first exhaust valve are configured to be opened/closed in opposite states; a second valve block comprising: a second intake valve and a second exhaust valve; the second intake valve and the second exhaust valve are configured to be opened/closed in opposite states; the control unit is used for setting states of the first air inlet valve and the second air inlet valve, and reaching corresponding first preset flow by setting ventilation duration of the first air inlet valve and preset pressure parameters of the first pressure controller; and setting the ventilation time length of the second air inlet valve and the preset pressure parameter of the second pressure controller to reach the corresponding second preset flow. On one hand, the pressure control meter is matched with exhaust to effectively reduce the pressure in the pipeline, so that pressure fluctuation caused by breath holding is avoided; on the other hand, the valve group can be utilized to rapidly switch gas, and the gas flow is accurately controlled through the press fit time.

Drawings

Fig. 1 shows a schematic structural diagram of a reactive gas switching system in an embodiment of the disclosure.

Fig. 2 shows a schematic diagram of the open and closed states of the first intake valve and the first exhaust valve in an embodiment of the present disclosure.

Fig. 3 shows a schematic diagram of the open and closed states of the second intake valve and the second exhaust valve in an embodiment of the present disclosure.

Fig. 4 shows a schematic structural diagram of a reactive gas switching system in a further embodiment of the present disclosure.

Fig. 5 shows a schematic structural diagram of a reactive gas switching system in a further embodiment of the present disclosure.

Fig. 6 shows a schematic structural diagram of a reactive gas switching system in another embodiment of the present disclosure.

Fig. 7 shows a schematic structural view of a plasma processing apparatus in an embodiment of the present disclosure.

Detailed Description

Other advantages and effects of the present disclosure will be readily apparent to those skilled in the art from the following detailed description of the embodiments of the disclosure given by way of specific examples. The disclosure may be embodied or applied in other specific forms and details, and various modifications and alterations may be made to the details of the disclosure in various respects, all without departing from the spirit of the disclosure. It should be noted that, without conflict, the embodiments of the present disclosure and features of the embodiments may be combined with each other.

The embodiments of the present disclosure will be described in detail below with reference to the attached drawings so that those skilled in the art to which the present disclosure pertains can easily implement the same. The present disclosure may be embodied in many different forms and is not limited to the embodiments described herein.

In the description of the present disclosure, references to the terms "one embodiment," "some embodiments," "examples," "particular examples," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present disclosure. Furthermore, the particular features, structures, materials, or characteristics may be combined in any suitable manner in any one or a group of embodiments or examples. Furthermore, various embodiments or examples, as well as features of various embodiments or examples, presented in this disclosure may be combined and combined by those skilled in the art without contradiction.

Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In the representations of the present disclosure, "a set" means two or more, unless specifically defined otherwise.

For the purpose of clarity of the present disclosure, components that are not related to the description are omitted, and the same or similar components are given the same reference numerals throughout the specification.

Throughout the specification, when a device is said to be "connected" to another device, this includes not only the case of "direct connection" but also the case of "indirect connection" with other elements interposed therebetween. In addition, when a certain component is said to be "included" in a certain device, unless otherwise stated, other components are not excluded, but it means that other components may be included.

Although the terms first, second, etc. may be used herein to connote various elements in some examples, the elements should not be limited by the terms. These terms are only used to distinguish one element from another element. For example, a first interface, a second interface, etc. Furthermore, as used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context indicates otherwise. It will be further understood that the terms "comprises," "comprising," "includes," and/or "including" specify the presence of stated features, steps, operations, elements, modules, items, categories, and/or groups, but do not preclude the presence, presence or addition of one or more other features, steps, operations, elements, modules, items, categories, and/or groups. The terms "or" and/or "as used herein are to be construed as inclusive, or meaning any one or any combination. Thus, "A, B or C" or "A, B and/or C" means "any of the following: a, A is as follows; b, a step of preparing a composite material; c, performing operation; a and B; a and C; b and C; A. b and C). An exception to this definition will occur only when a combination of elements, functions, steps or operations are in some way inherently mutually exclusive.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the language clearly indicates the contrary. The meaning of "comprising" in the specification is to specify the presence of stated features, regions, integers, steps, operations, elements, and/or components, but does not preclude the presence or addition of other features, regions, integers, steps, operations, elements, and/or components.

Although not differently defined, including technical and scientific terms used herein, all terms have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. The term append defined in commonly used dictionaries is interpreted as having a meaning that is consistent with the meaning of the relevant technical literature and the currently prompted message, and is not excessively interpreted as an ideal or very formulaic meaning, so long as no definition is made.

In the etching process of the plasma processing apparatus, the through silicon via etching requires the etching (etc) and Deposition (DEP) operations to be alternately switched with each other, and thus two paths of gases are required to be used in the etching process and to be switched with each other. However, in the related art, an etching system generally uses a gas Mass Flow Controller (MFC) to control the feeding and stopping of two process gases into the reaction chamber, on the one hand, when the related valve is closed, the pressure is increased due to closed-off gas-blocking of the pipeline, so that high-pressure gas is fed into the reaction chamber when the subsequent valve is opened, resulting in uncontrollable gas flow and affecting the chamber pressure. On the other hand, the switching time of the MFC is slow, and since it is provided at the gas source, even if it is closed, the reaction gas still exists in the line between the MFC and the reaction chamber, resulting in a large delay in the time for the complete switching between the final reaction gases to succeed.

In view of this, the embodiments of the present disclosure provide a reactive gas switching system that solves the problems in the related art.

As shown in fig. 1, a schematic structural diagram of a reactive gas switching system in an embodiment of the present disclosure is shown.

The reactant gas switching system 100 is used to switch at least a first reactant gas or a second reactant gas suitable for different types of operations into a reaction chamber 500 of a semiconductor processing apparatus. In some embodiments, the first reactive gas may be a reactive gas for etching and the second reactive gas may be a reactive gas for deposition; alternatively, the first reactive gas may be a reactive gas for deposition and the second reactive gas may be a reactive gas for etching. In some embodiments, the reactive gases of different operation types to be switched may be two or more, such as three, four, or more, with embodiments being given by way of example only and not limitation.

The reactant gas switching system 100 includes two gas flow paths corresponding to a first reactant gas source 200 for providing a first reactant gas and a second reactant gas source 300 for providing a second reactant gas, respectively. Specifically, the reactive gas switching system 100 includes: a first pressure controller 101 and a first valve set corresponding to a first reactant gas delivery, and a second pressure controller 102 and a second valve set corresponding to a second reactant gas delivery.

The first pressure controller 101 is connected to a first transfer line 103 for transferring a first reaction gas. The first pressure controller 101 is located at a front stage of the first valve group. The first pressure controller 101 may be preset with a preset pressure value for matching the pressure of the first reaction gas output from the first transmission line 103 to the first valve group with the preset pressure value.

The first valve group comprises a first inlet valve 104 and a first outlet valve 105. The first air inlet valve 104 is communicated with the first air inlet pipeline 106 from the first transmission pipeline 103 to the reaction cavity 500, and is used for switching on/off the first air inlet pipeline 106. The first exhaust valve 105 is connected in the first exhaust line 107 from the first transfer line 103 to an exhaust gas channel (forwarding), for switching on/off the first exhaust line 107.

The first intake valve 104 and the first exhaust valve 105 are configured to be opened/closed in opposite states, i.e., in a "conjugate" relationship, so as to be restricted to the delivery of the first reaction gas to the reaction chamber 500 through the first intake pipe 106 or the discharge of the first reaction gas through the first exhaust pipe 107. Specifically, when the first intake valve 104 is in an open state, the first exhaust valve 105 is in a closed state. Alternatively, when the first intake valve 104 is in a closed state, the first exhaust valve 105 may be in an open state. In some embodiments, the opposite open/close state between the first intake valve 104 and the first exhaust valve 105 may be such that there is no "hard conjugate" relationship with opening and closing. Illustratively, the first intake valve 104 and the first exhaust valve 105 are one and the other of a normally open valve and a normally closed valve, respectively. Normally closed valves remain closed and open only when needed. Normally open valves remain open and only when needed will the valve be closed.

Referring to fig. 2, the first intake valve 104 is a normally closed valve, and the first exhaust valve 105 is exemplified as a normally open valve. That is, the state in which the exhaust gas is not introduced into the reaction chamber 500 is maintained in a normal state. The first intake valve 104 and the first exhaust valve 105 may be controlled by a first control flow path 401 to switch the open/close state, and the first control flow path 401 may be provided with fluid by a first pilot valve module, and the fluid may be gas or liquid. In a further example, a first electromagnetic valve 402 is disposed in the first control flow channel 401, and the first electromagnetic valve 402 may be a two-position two-way electromagnetic valve, and may receive a control signal to open/close the first control flow channel 401. As can be seen from fig. 2, in a normal state, the first electromagnetic valve 402 disconnects the first control flow passage 401, the first intake valve 104 is in a normally closed state, and the first exhaust valve 105 is in a normally open state. When the first reaction gas is required to be introduced into the reaction chamber 500, the first electromagnetic valve 402 changes its state to turn on the first control flow channel 401, the first air inlet valve 104 is opened, the first air outlet valve 105 is closed, and the first reaction gas is introduced into the reaction chamber 500 through the first transmission line 103 and the first air inlet line 106.

The second pressure controller 102 communicates with a second transfer line 108 for transferring a second reaction gas, corresponding to the first pressure controller 101. The second pressure controller 102 is located at a front stage of the second valve block. The second pressure controller 102 may be preset with a preset pressure value for matching the pressure value of the second reaction gas output from the second transmission line 108 to the second valve group with the preset pressure value. The preset pressure values of the first pressure controller 101 and the second pressure controller 102 may be the same or different.

Corresponding to the first valve group, the second valve group comprises a second inlet valve 109 and a second outlet valve 110, as shown in fig. 1. The second air intake valve 109 is communicated with the second air intake line 111 from the second transfer line 108 to the reaction chamber 500 for turning on/off the second air intake line 111. The second exhaust valve 110 is connected to a second exhaust line 112 from the second transmission line 108 to the exhaust passage, for switching on/off the second exhaust line 112.

The second inlet valve 109 and the second outlet valve 110 are configured to be opened/closed in opposite states, i.e., in a "conjugate" relationship, so as to be restricted to supply the second reaction gas to the reaction chamber 500 through the second inlet pipe 111 or discharge the second reaction gas through the second outlet pipe 112. Specifically, when the second intake valve 109 is in an open state, the second exhaust valve 110 is in a closed state. Alternatively, when the second intake valve 109 is closed, the second exhaust valve 110 may be opened. In some embodiments, the opposite open/close states between the second intake valve 109 and the second exhaust valve 110 may also be a "hard conjugate" relationship. Illustratively, the first intake valve 104 and the first exhaust valve 105 are one and the other of a normally open valve and a normally closed valve, respectively.

Referring to fig. 3, the second intake valve 109 is a normally closed valve, and the second exhaust valve 110 is exemplified as a normally open valve. That is, the state in which the exhaust gas is not introduced into the reaction chamber 500 is maintained in a normal state. The second intake valve 109 and the second exhaust valve 110 may be controlled to switch the open/close state by a second control flow path 403, and the second control flow path 403 may be supplied by a second pilot valve module. In a further example, a second solenoid valve 404 is disposed in the second control flow path 403, and the second solenoid valve 404 may be a two-position two-way solenoid valve, and may receive a control signal to open/close the second control flow path 403. As can be seen from fig. 3, the second electromagnetic valve 404 normally opens the second control flow path 403, the second intake valve 109 is normally closed, and the second exhaust valve 110 is normally open. When the second reaction gas is required to be introduced into the reaction chamber 500, the second electromagnetic valve 404 changes its state to turn on the second control flow channel 403, the second air inlet valve 109 is opened, the second air outlet valve 110 is closed, and the second reaction gas is introduced into the reaction chamber 500 through the second transmission line 108 and the second air inlet line 111.

In some embodiments, the first intake valve 104, the first exhaust valve 105, the second intake valve 109, and the second exhaust valve 110 may be selectively responsive to a fast control valve, such as an atomic layer deposition diaphragm valve (ALD valve), having a fast response time (< 8 ms), and capable of rapidly switching the feed and shut-off of more than two gases.

In some embodiments, the first pressure CONTROLLER 101 and the second pressure CONTROLLER 102 are implemented as pressure control gauges (PRESSURE CONTROLLER/UNIVERSAL PRESSURE CONTROLLER, PC), which may be set to the pressure values.

According to the embodiment, due to the exhaust valves in the first valve group and the second valve group, the exhaust valve is kept open for exhausting when the reaction gas is not conveyed in the normal state, so that the pipeline of the whole system is not completely closed to hold breath, and the stability of the pipeline pressure is facilitated. The pressure control of the first pressure controller 101 and the second pressure controller 102 can be matched to better stabilize the pipeline pressure at the required pressure value.

In addition, by using the pipeline pressure precisely controlled by the first/second pressure controller and matching with the time (i.e. ventilation time) for controlling the conduction of the first/second air inlet pipeline through the first/second air inlet valve, the flow rate of the first/second reaction gas fed into the reaction cavity can be precisely controlled.

The mathematical relationship between fluid flow and line pressure, flow rate, and time is described below.

The flow formula of the fluid is as follows:

Q=A·v （1）

wherein Q is flow; a is the sectional area of the pipeline.

A=πD ² /4（2）

Wherein D is the diameter of the pipeline; v is the flow rate.

Substitution of formula (2) into (1) yields:

Q=πD ² ·v/4 （3）

for flow rate calculations in hydrodynamics, differential pressure (ΔP) is also an important factor. According to boyle's law, there is a relationship between differential pressure and flow rate:

（4）

wherein ΔP is the differential pressure, unit pressure; η is the viscosity of the fluid; l is the pipe length (in meters); d is the diameter of the pipeline; q is the flow.

From the formula (3) and the formula (4), the formula (5) can be obtained:

v=ΔP/(η·L) （5）；

let the outlet pressure of the first pressure controller or the second pressure controller be P. V=q·t is also obtained, and t is the ventilation time of the first intake valve or the second intake valve.

If the gas is an ideal gas with a mass of M and a molar mass of μ, the ideal state equation can be expressed as:

P·v=n·R·T （7）

wherein, R is a universal gas constant, the value of which is related to the unit of a state parameter, and R=8.31J/(mol seed K) in the international system of units; t is the temperature; n is M/mu, and in the embodiment, the gas feed quantity of the reaction chamber can be represented.

Substituting the previous formula into formula (7), one can obtain:

n=P·v/（R·T）=P·Q·t/（R·T）=P·A·ΔP·t/（η·L·R·T）（8）

based on the principle of formula (8), the first preset flow rate of the corresponding first reaction gas can be determined by setting the ventilation duration in the open state of the first intake valve 104 and the preset pressure parameter of the first pressure controller 101. And, by setting the ventilation duration in the open state of the second air inlet valve 109 and the preset pressure parameter of the second pressure controller 102, the second preset flow of the corresponding second reaction gas can be determined.

In some embodiments, see fig. 1, the reactant gas switching system 100 may include a control unit 113. The control unit 113 is configured to set the open/close states of the first intake valve 104, the first exhaust valve 105, the second intake valve 109, and the second exhaust valve 110. Specifically, the control unit 113 may be coupled to and control the first solenoid valve 402 and the second solenoid valve 404 in fig. 2 and 3 to control the valve states of the first valve bank and the second valve bank by setting on/off of the first control flow path 401 and the second control flow path 403, thereby achieving the alternating switching of etching and deposition. For example, in general, the control unit 113 may set the first intake valve 104 and the second intake valve 109 to be in opposite open/closed states to alternatively deliver the first reactant gas or the second reactant gas to the reaction chamber 500. For example, the control unit 113 sends opposite valve control instructions to the first solenoid valve 402 and the second solenoid valve 404, respectively, to turn on the first control flow passage 401 and turn off the second control flow passage 403, or to turn off the first control flow passage 401 and turn on the second control flow passage 403. Alternatively, in some specific cases, the control unit 113 may send the same valve control command to the first solenoid valve 402 and the second solenoid valve 404, so that the first intake valve 104 and the second intake valve 109 are opened and closed simultaneously. Therefore, the opposite valve state between the first air inlet valve 104 and the second air inlet valve 109 can be actually in a "soft conjugate" state, and can be changed by a valve control command, so that the valve has better flexibility and can adapt to the normal scenes with opposite opening and closing of two air paths and the specific scenes with the same opening and closing.

In some embodiments, the first reactant gas source 200 may have a mass flow controller, which is connected to the first gas inlet line and is located in front of the first pressure controller 101, for outputting the first reactant gas to the first pressure controller 101 with a precise control of various gas ratios. The second reactant gas source 300 may have a mass flow controller for outputting a second reactant gas to the second pressure controller 102 that precisely controls the ratio of the various gases.

As shown in fig. 4, a schematic structural diagram of a reactive gas switching system 100 in a further embodiment of the present disclosure is shown.

In contrast to the embodiment of fig. 1, in addition to the first pressure controller 101, the second pressure controller 102, the first valve set, the second valve set, etc., in the embodiment of fig. 4, the first reactant gas source 200 communicates with the first set of mass flow controllers 201 and the second reactant gas source communicates with the second set of mass flow controllers 301.

The first set of mass flow controllers 201 is in communication between the first reactant gas source 200 and the first pressure controller 101. The first set of mass flow controllers 201 includes a plurality of first mass flow controllers. Each of the first mass flow controllers is used for controlling one path of first reaction gas, and output pipelines of the first mass flow controllers are connected to output the mixed multiple paths of first reaction gas to the first pressure controller 101. In some embodiments, the flow parameters of the first reactive gases controlled by the first mass flow controllers may be all different or partially the same, and by mixing multiple paths of the first reactive gases according to a preset ratio to achieve a precise required ratio, the mixed first reactive gases are output to the first pressure controller 101, which is more beneficial to precisely controlling the pipeline pressure and the respective ratio contents of the first reactive gases fed into the reaction chamber 500.

The second set of mass flow controllers 301 is in communication between the second reactant gas source 300 and the second pressure controller 102; the second set of mass flow controllers 301 includes a plurality of second mass flow controllers; each of the second mass flow controllers is configured to control one path of the second reaction gas, and output pipelines of the second mass flow controllers are connected to mix the multiple paths of the second reaction gas and output the mixed second reaction gas to the second pressure controller 102. In some embodiments, the flow parameters of the second reaction gases controlled by the second mass flow controllers may be all different or partially the same, and by mixing the multiple paths of second reaction gases according to a preset ratio to achieve a precise required ratio, the mixed second reaction gases are output to the second pressure controller 102, which is more beneficial to precisely controlling the pipeline pressure and the respective ratio contents of the second reaction gases fed into the reaction chamber 500.

Based on the above embodiments, it can be appreciated that the reaction gas flows toward one end of the reaction chamber 500 or toward one end of the exhaust passage. The gas path resistance at the exhaust channel is typically greater than the line resistance at one end of reaction chamber 500.

For this reason, it can be seen that fig. 5 shows a schematic structural diagram of a reactant gas switching system according to still another embodiment of the present disclosure.

The reactant gas switching system of the embodiment of fig. 5 is illustrated with the addition of a flow restrictor 114 to the reactant gas switching system 100 of fig. 1.

Specifically, the first air inlet pipe 106 and the second air inlet pipe 111 have a common section in communication with the reaction chamber 500, and the restrictor 114 is provided in the common section. The restrictor 114 serves to increase the line resistance to the same resistance at the utility section as at the exhaust passage. Further, the first valve group and the second valve group can keep the gas path resistance environment as the same as possible when the flow direction of the reaction gas is switched (the flow direction is switched to the reaction chamber 500 or the exhaust channel), and the flow speed fluctuation and the pressure fluctuation generated during the switching are reduced. In a further example, the resistance of the restrictor 114 may be empirically set, or the resistance of the restrictor 114 may be continuously adjusted according to the measured flow rate at the exhaust channel, where the resistance (or flow rate) at both ends of the reaction chamber 500 and the exhaust channel may be the same when the pressure of the first pressure controller 101 and the second pressure controller 102 is stable.

In some embodiments, regarding the automatic adjustment of the resistance of the flow restrictor 114, for example, the resistance of the flow restrictor 114 may be adjusted by feedback control (e.g., PID) to bring the resistances measured by the first and second resistance sensors close to equal by providing a first resistance sensor and a second resistance sensor in the exhaust passage, respectively, and in the common section. The outlet of the air inlet valve is consistent with the outlet pressure of the air outlet valve (namely, the two paths of pressure drops are consistent), and the pressure can be ensured not to fluctuate during switching.

In some embodiments, as shown in fig. 6, a schematic structural diagram of a reactive gas switching system in another embodiment of the present disclosure is shown. In the system of fig. 6, automatic adjustment of restrictor 114 resistance may be achieved. Illustratively, the exhaust passage communicates with the pumping pump 700 and the reaction chamber 500 communicates with the setup chamber pumping pump 600 (e.g., molecular pump). A pressure gauge 800 is installed on the reaction chamber 500. When the resistance of the restrictor 114 is adjusted, the pumping speed between the pumping pump 700 and the chamber pressure pump 600 is controlled by the control unit 113, and the valve opening of the gas path and the exhaust channel between the reaction chamber 500 and the first and second reaction gas sources is kept unchanged, so that any group of exhaust valves and intake valves are switched from the exhaust and intake states to the intake and exhaust states. The restrictor opening is adjusted according to the pressure fluctuation exhibited by pressure gauge 800 of reaction chamber 500. Through the multiple adjustments, the reading of the pressure gauge 800 gradually becomes stable when the state is switched, and the opening of the restrictor 114 is the target opening, i.e. is adjusted to the target resistance.

In some embodiments, the restrictor 114 may be a flow limiting plate, and may be specifically implemented by a metal plate with holes, and is installed at the pipe joint and directly clamped by the male and female heads, so that the flow rate balancing effect is better at two ends although the structure is simple.

Embodiments of the present disclosure may also provide a plasma processing apparatus, including: the reactive gas switching system as described in the previous embodiment.

The principle and possible structure of the plasma processing apparatus may be exemplarily described with reference to fig. 7.

The plasma processing apparatus has a reaction chamber 500. An upper electrode 501 and a lower electrode 502 may be disposed in the reaction chamber 500, the lower electrode 502 having a pedestal 503 and an electrostatic chuck 504 (ESC) positioned above the pedestal 503, the electrostatic chuck 504 being configured to hold and chuck a wafer. A confinement ring 505 is disposed about the periphery of the pedestal 503 to separate a processing region 506 between the upper and lower electrodes 502 above the confinement ring 505 and an exhaust region 507 below the confinement ring 505. The processing region 506 applies a radio frequency electric field for ionizing the introduced reactant gases into a plasma for etching or deposition of the wafer. The exhaust region 507 communicates with an exhaust device 508, such as a vacuum pump or the like, for extracting contaminants generated by the reaction.

The reaction chamber 500 is connected to at least a first reaction gas source 200 and a second reaction gas source 300 for etching and deposition gas sources through the reaction gas switching system 100 in any of the embodiments of the present disclosure. An exhaust passage in the reactant gas switching system 100 may be communicated to the exhaust region to exhaust the excess reactant gas.

It should be noted that the number of the reactive gas sources is not limited to two, and for example, there may be a plurality of etching reactive gases and/or deposition reactive gases required based on the requirements of different etching processes and/or different deposition processes, so that a larger number of reactive gas sources may be provided. It will be appreciated that as shown in fig. 1 or 4, each additional reactant gas source may be provided with a corresponding pressure controller, valve block, and a set of mass flow controllers for the additional reactant gas source.

In summary, embodiments of the present disclosure provide a reactive gas switching system and a plasma processing apparatus, where the reactive gas switching system includes: a first pressure controller communicated in a first transfer line for delivering a first reactant gas; the second pressure controller is communicated in a second transmission pipeline for conveying a second reaction gas; a first valve block comprising: a first intake valve and a first exhaust valve; the first intake valve and the first exhaust valve are configured to be opened/closed in opposite states; a second valve block comprising: a second intake valve and a second exhaust valve; the second intake valve and the second exhaust valve are configured to be opened/closed in opposite states; the control unit is used for setting states of the first air inlet valve and the second air inlet valve, and reaching corresponding first preset flow by setting ventilation duration of the first air inlet valve and preset pressure parameters of the first pressure controller; and setting the ventilation time length of the second air inlet valve and the preset pressure parameter of the second pressure controller to reach the corresponding second preset flow. On one hand, the pressure control meter is matched with exhaust to effectively reduce the pressure in the pipeline, so that pressure fluctuation caused by breath holding is avoided; on the other hand, the valve group can be utilized to rapidly switch gas, and the gas flow is accurately controlled through the press fit time.

The above embodiments are merely illustrative of the principles of the present disclosure and its efficacy, and are not intended to limit the disclosure. Modifications and variations may be made to the above-described embodiments by those of ordinary skill in the art without departing from the spirit and scope of the present disclosure. Accordingly, it is intended that all equivalent modifications and variations which a person having ordinary skill in the art would accomplish without departing from the spirit and technical spirit of the present disclosure be covered by the claims of the present disclosure.

Claims

1. A reactive gas switching system for switching at least a first reactive gas or a second reactive gas suitable for different operation types into a reaction chamber of a semiconductor processing apparatus; the reactive gas switching system includes:

a first pressure controller communicated in a first transfer line for delivering a first reactant gas;

the second pressure controller is communicated in a second transmission pipeline for conveying a second reaction gas;

a first valve block comprising: the first air inlet valve is communicated with the first transmission pipeline to a first air inlet pipeline of the reaction cavity; the first exhaust valve is communicated with the first exhaust pipeline from the first transmission pipeline to the exhaust channel; wherein the first intake valve and the first exhaust valve are configured to be opened/closed in opposite states;

a second valve block comprising: the second air inlet valve is communicated with the second transmission pipeline to a second air inlet pipeline of the reaction cavity; the second exhaust valve is communicated in a second exhaust pipeline from the second transmission pipeline to the exhaust channel; wherein the second intake valve and the second exhaust valve are configured to be opened/closed in opposite states;

a common section communicated with the reaction cavity is arranged between the first air inlet pipeline and the second air inlet pipeline, and a restrictor for increasing the pipeline resistance to be the same as the resistance at the position of the exhaust channel is arranged in the common section; the exhaust channel is communicated with the air extracting pump, and the reaction cavity is communicated with the cavity pressure pump; the reaction cavity is provided with a pressure gauge; the pumping speed between the pumping pump and the cavity pressure pump is controlled to be unchanged through a control unit, and the valve opening of a gas path and a valve opening of an exhaust channel between the reaction cavity and a first reaction gas source and a second reaction gas source are kept unchanged, so that a first valve group or a second valve group is switched to adjust the opening of the flow restrictor according to pressure fluctuation displayed by the pressure gauge until the reading of the pressure gauge is stable;

the ventilation time length of the first air inlet valve in the opening state and the preset pressure parameter of the first pressure controller can be set so as to determine the first preset flow of the corresponding first reaction gas; and the ventilation time length of the second air inlet valve in the opening state and the preset pressure parameter of the second pressure controller can be set so as to determine the second preset flow of the corresponding second reaction gas.

2. The reactive gas switching system according to claim 1, wherein the first intake valve and the second intake valve are disposed in opposite open/close states; and/or, the reactive gas switching system comprises: the control unit is used for setting valve states of the first valve group and the second valve group and setting preset pressure parameters of the first pressure controller and the second pressure controller; and/or the first air inlet valve, the first air outlet valve, the second air inlet valve and the second air outlet valve are atomic layer deposition diaphragm valves; and/or the first and second reactant gases are adapted to reactant gases for semiconductor etching and deposition, respectively.

3. The reactive gas switching system according to claim 1, wherein:

a first set of mass flow controllers in communication between a first reactant gas source and a first pressure controller; the first set of mass flow controllers includes a plurality of first mass flow controllers; each first mass flow controller is used for controlling one path of first reaction gas, and the output pipelines of the first mass flow controllers are connected so as to mix multiple paths of first reaction gases and output the mixed gases to the first pressure controller;

a second set of mass flow controllers in communication between a second reactant gas source and a second pressure controller; the second set of mass flow controllers includes a plurality of second mass flow controllers; each second mass flow controller is used for controlling one path of second reaction gas, and the output pipelines of the second mass flow controllers are connected to output the mixed multiple paths of second reaction gas to the second pressure controller.

4. The reactive gas switching system of claim 1, wherein the first intake valve and the first exhaust valve are one and the other of a normally open valve and a normally closed valve, respectively;

the first air inlet valve and the first air outlet valve are controlled by a first control flow passage supplied by the first pilot valve module to switch the open/close state, and a first electromagnetic valve which is coupled with and controlled by the control unit is arranged in the first control flow passage.

5. The reactive gas switching system of claim 4, wherein the first intake valve is a normally closed valve and the first exhaust valve is a normally open valve.

6. The reactive gas switching system of claim 1, wherein the second intake valve and the second exhaust valve are one and the other of a normally open valve and a normally closed valve, respectively;

the second air inlet valve and the second air outlet valve are controlled by a second control flow passage supplied by a second pilot valve module to switch the open/close state, and a second electromagnetic valve which is coupled with and controlled by the control unit is arranged in the second control flow passage.

7. The reactive gas switching system of claim 6, wherein the second intake valve is a normally closed valve and the second exhaust valve is a normally open valve.

8. A plasma processing apparatus, comprising: the reactive gas switching system according to any one of claims 1 to 7.