A special gas safety control device

Abstract

An embodiment of the present invention provides a special gas safety control method and a semiconductor process equipment, the method comprising: obtaining a chamber pressure value; when the pressure value is greater than a preset pressure threshold, when the second and third gas valves need to be opened, controlling the first circuit to be disconnected and the second and third circuits to be connected, so that the first gas valve is closed and the second and third gas valves are opened; when the first gas valve needs to be opened, controlling the first circuit to be closed and the second and third circuits to be disconnected, so that the first gas valve is opened and the second and third gas valves are closed. By incorporating valve interlocks into the circuit design, the first gas valve, the second gas valve, and the third gas valve are not opened simultaneously, thereby avoiding the risk of software control failure, preventing chemical reactions between the special gases from generating byproducts, causing damage to hardware and injury to personnel, eliminating safety hazards, and protecting the safety of the system and personnel.

Description

[0001] This application is a divisional application of the patent application with the application date of July 29, 2022, application number 202210905961.1, and invention name “A special gas safety control method and semiconductor process equipment”. Technical Field

[0002] The present invention relates to the field of semiconductor technology, and in particular to a special gas safety control method and a semiconductor process equipment. Background Art

[0003] CVD (Chemical Vapor Deposition) is a method for depositing a substance onto a substrate surface in the form of an atomic film. With the advancement of microelectronics and deep-submicron chip technology, the dimensions of devices and materials are constantly decreasing, while the aspect ratios of devices are increasing. The advantages of CVD in filling materials are becoming increasingly apparent, making this process increasingly popular in the semiconductor industry.

[0004] A hallmark of the CVD process is the introduction of multiple process gases into the chamber. Once the chamber environment is in place, the process gases enter simultaneously and adhere to the wafer, reacting on the wafer surface to form the desired thin film. Simultaneously, a vacuum pump is required to continuously remove byproducts and residual reactants. CVD process gases can contain a variety of specialty gases, which are flammable, explosive, toxic, and corrosive, such as H2, WF6, 5% B2H6 / 95% N2, NF3, and SiH4.

[0005] In the prior art, a software program controls the interlocking between valves according to the interlocking conditions of the special gas valves. However, the software has the risk of failure and poses a safety hazard. Summary of the Invention

[0006] In view of the above problems, embodiments of the present invention are proposed to provide a special gas safety control method and corresponding semiconductor process equipment that overcome the above problems or at least partially solve the above problems.

[0007] To address the above-mentioned issues, an embodiment of the present invention discloses a special gas safety control method, which is applied to semiconductor process equipment. The semiconductor process equipment includes: a process chamber and a control circuit; the control circuit includes a first circuit for controlling the on / off of a valve corresponding to a first gas, a second circuit for controlling the on / off of a valve corresponding to a second gas, and a third circuit for controlling the on / off of a valve corresponding to a third gas. The method includes:

[0008] obtaining a pressure value of the process chamber;

[0009] When the pressure value is greater than a preset pressure threshold, when it is necessary to open the second gas corresponding valve and the third gas corresponding valve, the first circuit is controlled to be disconnected, and the second circuit and the third circuit are controlled to be connected, so that the first gas corresponding valve is closed and the second gas corresponding valve and the third gas corresponding valve are opened;

[0010] When the first gas corresponding valve needs to be opened, the first circuit is controlled to be closed, and the second circuit and the third circuit are controlled to be disconnected, so that the first gas corresponding valve is opened and the second gas corresponding valve and the third gas corresponding valve are closed.

[0011] Optionally, it also includes:

[0012] When the pressure value is less than or equal to the preset pressure threshold, the first circuit, the second circuit, and the third circuit are controlled to be connected so that the first gas corresponding valve, the second gas corresponding valve, and the third gas corresponding valve are opened.

[0013] Optionally, the control circuit further includes: a first relay, a second relay, and a third relay, and the method further includes:

[0014] obtaining a pressure value of the process chamber, and when the pressure value is greater than a preset pressure threshold, controlling the second relay to be turned on and the third relay to be turned off via the first relay, so that the second relay controls the on and off of the first circuit, the second circuit, and the third circuit;

[0015] When the pressure value is less than or equal to the preset pressure threshold, the first relay controls the second relay to be disconnected and the third relay to be connected, so that the third relay controls the on and off of the first circuit, the second circuit, and the third circuit.

[0016] Optionally, the first relay includes a first pair of normally closed contacts and a first pair of normally open contacts; when the pressure value is greater than the preset pressure threshold, controlling the second relay to be turned on and the third relay to be turned off by the first relay, so that the second relay controls the on and off of the first circuit, the second circuit, and the third circuit, includes:

[0017] When the pressure value is greater than the preset pressure threshold, the first pair of normally open contacts are controlled by the first relay to remain in an open state to control the third relay to be disconnected, and the first pair of normally closed contacts are controlled by the first relay to remain in a closed state to control the second relay to be connected, so that the second relay controls the on and off of the first circuit, the second circuit and the third circuit.

[0018] Optionally, the second relay includes a second pair of normally closed contacts, a second pair of normally open contacts, and a third pair of normally open contacts; and when the pressure value is greater than a preset pressure threshold and the second gas corresponding valve and the third gas corresponding valve need to be opened, the first circuit is controlled to be disconnected, and the second circuit and the third circuit are controlled to be connected, so that the first gas corresponding valve is closed and the second gas corresponding valve and the third gas corresponding valve are opened, comprising:

[0019] The second pair of normally closed contacts is controlled to be disconnected by the second relay, and the first circuit is controlled to be disconnected. The second pair of normally open contacts and the third pair of normally open contacts are controlled to be closed by the second relay, and the second circuit and the third circuit are controlled to be connected, so that the valve corresponding to the first gas is closed and the valve corresponding to the second gas and the valve corresponding to the third gas are opened.

[0020] Optionally, when the valve corresponding to the first gas needs to be opened, controlling the first circuit to be closed, and controlling the second circuit and the third circuit to be disconnected, so that the valve corresponding to the first gas is opened and the valve corresponding to the second gas and the valve corresponding to the third gas are closed, includes:

[0021] The second pair of normally closed contacts is controlled by the second relay to remain in a closed state, and the first circuit is controlled to be connected. The second pair of normally open contacts and the third pair of normally open contacts are controlled by the second relay to remain in an open state, and the second circuit and the third circuit are controlled to be disconnected, so that the valve corresponding to the first gas is opened and the valve corresponding to the second gas and the valve corresponding to the third gas are closed.

[0022] Optionally, when the pressure value is less than or equal to the preset pressure threshold, controlling the second relay to be disconnected and the third relay to be connected by the first relay, so that the third relay controls the on and off of the first circuit, the second circuit, and the third circuit, includes:

[0023] When the pressure value is less than or equal to the preset pressure threshold, the first pair of normally closed contacts are controlled to open and the second relay is controlled to disconnect through the first relay, and the first pair of normally open contacts are controlled to close and the third relay is controlled to be connected, so that the third relay controls the on and off of the first circuit, the second circuit and the third circuit.

[0024] Optionally, the third relay includes a fourth pair of normally open contacts, a fifth pair of normally open contacts, and a sixth pair of normally open contacts; and when the pressure value is less than or equal to the preset pressure threshold, controlling the first circuit, the second circuit, and the third circuit to be connected so that the valve corresponding to the first gas, the valve corresponding to the second gas, and the valve corresponding to the third gas are opened includes:

[0025] The fourth pair of normally open contacts, the fifth pair of normally open contacts and the sixth pair of normally open contacts are controlled to be closed through the third relay, and the first circuit, the second circuit and the third circuit are controlled to be connected, so that the first gas corresponding valve, the second gas corresponding valve and the third gas corresponding valve are opened.

[0026] Optionally, the first gas is NF3, the second gas is H2, and the third gas is SiH4.

[0027] An embodiment of the present invention further discloses a semiconductor process device, comprising: a process chamber, and a control circuit; the control circuit comprising a first circuit for controlling the on / off of a valve corresponding to a first gas, a second circuit for controlling the on / off of a valve corresponding to a second gas, and a third circuit for controlling the on / off of a valve corresponding to a third gas; the semiconductor process device further comprising:

[0028] A controller for obtaining a pressure value of the process chamber; when the pressure value is greater than a preset pressure threshold, when it is necessary to open the second gas corresponding valve and the third gas corresponding valve, controlling the first circuit to be disconnected, and controlling the second circuit and the third circuit to be connected, so that the first gas corresponding valve is closed and the second gas corresponding valve and the third gas corresponding valve are opened; when it is necessary to open the first gas corresponding valve, controlling the first circuit to be closed, and controlling the second circuit and the third circuit to be disconnected, so that the first gas corresponding valve is opened and the second gas corresponding valve and the third gas corresponding valve are closed.

[0029] Optionally, the controller is also used to control the first circuit, the second circuit and the third circuit to be connected when the pressure value is less than or equal to the preset pressure threshold, so that the first gas corresponding valve, the second gas corresponding valve and the third gas corresponding valve are opened.

[0030] Optionally, the control circuit also includes: a first relay, a second relay and a third relay. The controller is also used to obtain the pressure value of the process chamber. When the pressure value is greater than the preset pressure threshold, the first relay controls the second relay to be connected and the third relay to be disconnected, so that the second relay controls the on and off of the first circuit, the second circuit and the third circuit; when the pressure value is less than or equal to the preset pressure threshold, the first relay controls the second relay to be disconnected and the third relay to be connected, so that the third relay controls the on and off of the first circuit, the second circuit and the third circuit.

[0031] Optionally, the first relay includes a first pair of normally closed contacts and a first pair of normally open contacts; the controller is used to control the first pair of normally open contacts to remain in an open state and control the third relay to be disconnected when the pressure value is greater than a preset pressure threshold, and to control the first pair of normally closed contacts to remain in a closed state and control the second relay to be connected, so that the second relay controls the on and off of the first circuit, the second circuit and the third circuit.

[0032] Optionally, the second relay includes a second pair of normally closed contacts, a second pair of normally open contacts and a third pair of normally open contacts; the controller is used to control the second pair of normally closed contacts to be disconnected through the second relay, control the first circuit to be disconnected, and control the second pair of normally open contacts and the third pair of normally open contacts to be closed through the second relay, control the second circuit and the third circuit to be connected, so that the first gas corresponding valve is closed and the second gas corresponding valve and the third gas corresponding valve are opened.

[0033] Optionally, the controller is used to control the second pair of normally closed contacts to remain in a closed state through the second relay, control the first circuit to be connected, and control the second pair of normally open contacts and the third pair of normally open contacts to remain in an open state through the second relay, control the second circuit and the third circuit to be disconnected, so that the first gas corresponding valve is opened and the second gas corresponding valve and the third gas corresponding valve are closed.

[0034] Optionally, the controller is used to control the first pair of normally closed contacts to open and the second relay to disconnect through the first relay when the pressure value is less than or equal to the preset pressure threshold, and to control the first pair of normally open contacts to close and the third relay to turn on through the first relay, so that the third relay controls the on and off of the first circuit, the second circuit and the third circuit.

[0035] Optionally, the third relay includes a fourth pair of normally open contacts, a fifth pair of normally open contacts and a sixth pair of normally open contacts; the controller is used to control the closure of the fourth pair of normally open contacts, the fifth pair of normally open contacts and the sixth pair of normally open contacts through the third relay, and control the connection of the first circuit, the second circuit and the third circuit, so that the first gas corresponding valve, the second gas corresponding valve and the third gas corresponding valve are opened.

[0036] Optionally, the first gas is NF3, the second gas is H2, and the third gas is SiH4.

[0037] The embodiments of the present invention include the following advantages:

[0038] In an embodiment of the present invention, a pressure value of the process chamber is obtained; when the pressure value is greater than a preset pressure threshold, when it is necessary to open the valve corresponding to the second gas and the valve corresponding to the third gas, the first circuit is controlled to be disconnected, and the second circuit and the third circuit are controlled to be connected, so that the valve corresponding to the first gas is closed and the valve corresponding to the second gas and the valve corresponding to the third gas are opened; when it is necessary to open the valve corresponding to the first gas, the first circuit is controlled to be closed, and the second circuit and the third circuit are controlled to be disconnected, so that the valve corresponding to the first gas is opened and the valve corresponding to the second gas and the valve corresponding to the third gas are closed. By incorporating valve interlocks into the circuit design, when the process chamber pressure reaches the preset threshold, the first and second gas valves and the first and third gas valves will not be opened simultaneously, thereby avoiding the risk of software control failure, preventing chemical reactions between the specialty gases from generating byproducts that could damage hardware and injure personnel, eliminating safety hazards, and protecting the safety of the system and personnel. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 This is a flowchart of a method for safety control of special gases provided by an embodiment of the present invention;

[0040] Figure 2 This is a schematic diagram of a special gas safety control principle provided by an embodiment of the present invention;

[0041] Figure 3 This is a structural block diagram of a semiconductor process equipment provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0042] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0043] The present invention uses the tungsten chemical vapor deposition process (CVD W process) as an example. The CVD W process is primarily used for depositing tungsten metal thin films in the 28-14nm technology generation. The specialty gases used in the CVD W equipment include: H2, WF6, 5% B2H6 / 95% N2, NF3, and SiH4. The Material Safety Data Sheet (MSDS) for each gas is as follows:

[0044] 1.H2:

[0045] Hazard Overview: Hydrogen is a colorless, odorless, flammable compressed gas stored in high-pressure cylinders. Fire or explosion can occur at any time when the hydrogen content in the air exceeds 4%.

[0046] Molecular weight: 2.016.

[0047] Boiling point: (1 atmosphere) -423.0F (-252.8C).

[0048] Chemical stability: stable.

[0049] Incompatibility: Oxidizing agents.

[0050] 2.B2H6:

[0051] Hazard Overview: A colorless, highly toxic, extremely flammable gas sold mixed with argon, helium, hydrogen, or nitrogen. The gas has a sickening sweet odor. It can be fatal if inhaled or absorbed through the skin.

[0052] Molecular weight: 27.67.

[0053] Boiling point: (1 atmosphere) -135.1F (-92.8C).

[0054] Chemical stability: Unstable.

[0055] Incompatibilities: Oxidizing agents, aluminum, lithium, halides and metal oxides.

[0056] 3.WF6:

[0057] Hazard Overview: Toxic, corrosive, non-flammable liquefied gas that hydrolyzes into corrosive hydrofluoric acid upon contact with moisture. Inhalation or contact with skin can cause severe chemical burns.

[0058] Molecular weight: 297.8.

[0059] Boiling point: (1 atmosphere) 62.7F (17.2C).

[0060] Chemical stability: stable.

[0061] Reactivity: Hydrolysis produces hydrofluoric acid and tungsten oxyfluoride.

[0062] 4.NF3:

[0063] Hazard Overview: Toxic, non-flammable compressed gas. It is an oxidizer and can cause or promote combustion of metallic and non-metallic materials.

[0064] Molecular weight: 71.0.

[0065] Boiling point: (1 atmosphere) -200.3F (-129.1C).

[0066] Chemical stability: stable.

[0067] Incompatibility: Oils, greases, hydrocarbons.

[0068] 5.SiH4:

[0069] Hazard Overview: Silane is a colorless, air-reactive, asphyxiating gas that will typically burn upon contact with air and emit thick, white, amorphous silicon dioxide fumes.

[0070] Molecular weight: 32.12.

[0071] Boiling point: (1 atmosphere) -169.0F (-111.7C).

[0072] Chemical stability: spontaneous combustion, will spontaneously combust when exposed to air.

[0073] Incompatibilities: Air, other oxidizing agents and moisture.

[0074] It can be seen that gas safety design is an important part of CVD W equipment.

[0075] Among the special gases used in CVD W machines, H2 and SiH4 are reducing agents, while NF3 is an oxidizing agent. The chemical bond energy of NF3 is relatively weak and unstable. Under certain conditions, NF3 can react chemically with H2. The chemical equation is:

[0076] NF3+3H2=NH3+6HF

[0077] NF3 can react chemically with SiH4, and the chemical equation is:

[0078] 8NF3+3SiH4=4N2+3SiF4+12HF

[0079] The reaction products, SiF4 and NH3, can contaminate the chamber and piping. Furthermore, HF, one of the reactants, is toxic and corrosive, potentially damaging hardware and posing safety risks. Since gas concentration is proportional to chamber pressure, when chamber pressure is below a certain value (e.g., 10 Torr), the gas concentration is low and the gas molecules are inactive, making chemical reactions less likely and eliminating the need for electrical interlocking.

[0080] When the process chamber pressure reaches a certain value (e.g., greater than 10 Torr), the above chemical reactions must be prevented from occurring. The NF3 and H2 valves must not be opened at the same time, and the NF3 and SiH4 valves must not be opened at the same time.

[0081] In the prior art, the opening and closing of the special gas valve is controlled by software according to preset interlocking conditions. For example, when one or more of the conditions such as the chamber cover is closed, the pressure difference between the gas cabinet and the environment is greater than the alarm value, and the chamber gas cabinet door is closed are not met, the special gas valve is not allowed to open, which can prevent the leakage of special gases into the air; when one or more of the alarms such as the coolant leakage alarm, the chamber overtemperature sensor alarm, and the smoke sensor alarm are detected, the special gas valve is closed, and the special gas circulation can be prohibited in time when an abnormal situation occurs to prevent more serious hazards.

[0082] Although the interlocking between valves is done by software in the current design, there is a risk of software failure, and this function needs to be added to the electrical design.

[0083] One of the core concepts of the embodiments of the present invention is to provide a new special gas valve control method, which controls the switching of the special gas valve through a circuit so that when the pressure in the process chamber is greater than a preset pressure threshold, the first gas valve and the second gas valve will not be opened at the same time, and the first gas valve and the third gas valve will not be opened at the same time, thereby avoiding the risk of software control failure, preventing chemical reactions between special gases from generating by-products, causing hardware damage and personal injury, eliminating safety hazards, and protecting the safety of the system and personnel.

[0084] Reference Figure 1 , shows a flowchart of the steps of a special gas safety control method provided by an embodiment of the present invention, which is applied to semiconductor process equipment. The semiconductor process equipment includes: a process chamber, and a control circuit; the control circuit includes a first circuit for controlling the on / off of a valve corresponding to a first gas, a second circuit for controlling the on / off of a valve corresponding to a second gas, and a third circuit for controlling the on / off of a valve corresponding to a third gas. The method may specifically include the following steps:

[0085] Step 101, obtaining the pressure value of the process chamber;

[0086] Illustratively, in an embodiment of the present invention, the control circuit may further include a controller (PLC, Programmed Logic Controller) configured to obtain a pressure value signal of the process chamber and output a level signal to the control circuit.

[0087] In one embodiment of the present invention, the control circuit further includes: a first relay, a second relay and a third relay, and the method further includes: obtaining the pressure value of the process chamber, and when the pressure value is greater than the preset pressure threshold, controlling the second relay to be connected and the third relay to be disconnected through the first relay, so that the second relay controls the on and off of the first circuit, the second circuit and the third circuit; when the pressure value is less than or equal to the preset pressure threshold, controlling the second relay to be disconnected and the third relay to be connected through the first relay, so that the third relay controls the on and off of the first circuit, the second circuit and the third circuit.

[0088] As an example, in an embodiment of the present invention, the second relay and the third relay can be controlled to be on and off by the first relay; the first circuit, the second circuit and the third circuit can be controlled to be on and off by the second relay and / or the third relay.

[0089] For example, the PLC can transmit a control signal to the first relay to control the corresponding contact of the first relay to close or open, thereby controlling the corresponding contacts of the second and third relays to close or open. When the pressure value of the process chamber is greater than a preset pressure threshold, the first relay can control the second relay to close and the third relay to open, so that the second relay controls the on and off of the first, second, and third circuits. When the pressure value is less than or equal to the preset pressure threshold, the first relay can control the second relay to open and the third relay to close, so that the third relay controls the on and off of the first, second, and third circuits.

[0090] Step 102: When the pressure value is greater than a preset pressure threshold and it is necessary to open the second gas corresponding valve and the third gas corresponding valve, the first circuit is controlled to be disconnected and the second circuit and the third circuit are controlled to be connected, so that the first gas corresponding valve is closed and the second gas corresponding valve and the third gas corresponding valve are opened.

[0091] For example, the control circuit may include a first circuit, a second circuit, and a third circuit, wherein the first circuit may control the on / off of the first gas valve, the second circuit may control the on / off of the second gas valve, and the third circuit may control the on / off of the third gas valve.

[0092] For example, if the pressure in the process chamber exceeds a preset pressure threshold, it indicates a high concentration of specialty gases within the process chamber, making it easy for the specialty gases to react with each other and contaminate the process chamber and pipelines. When the second and third gas valves need to be opened, the first circuit can be disconnected and the second and third circuits can be connected, closing the first gas valve and opening the second and third gas valves.

[0093] In one embodiment of the present invention, the first relay includes a first pair of normally closed contacts and a first pair of normally open contacts; when the pressure value is greater than the preset pressure threshold, the first pair of normally open contacts are controlled by the first relay to remain in an open state to control the third relay to be disconnected, and the first pair of normally closed contacts are controlled by the first relay to remain in a closed state to control the second relay to be connected, so that the second relay controls the on and off of the first circuit, the second circuit and the third circuit.

[0094] For example, the first relay may include a first pair of normally closed contacts and a first pair of normally open contacts. When the process chamber pressure is greater than a preset pressure threshold, the PLC may output a low-level signal to the first relay. Upon receiving the low-level signal, the first relay may control the first pair of normally open contacts to remain in an open state, thereby disconnecting the third relay, and may control the first pair of normally closed contacts to remain in a closed state, thereby connecting the second relay. When the second relay is in the connected state, it may control the on and off of the first circuit, the second circuit, and the third circuit.

[0095] For example, Figure 2 The diagram shows a schematic diagram of a specialty gas safety control system according to an embodiment of the present invention. KA01 is the first relay, KA02 is the second relay, and KA03 is the third relay. The first relay KA01 includes a first pair of normally closed contacts 11 and 12 for controlling the on / off operation of the second relay KA02, and a first pair of normally open contacts 13 and 14 for controlling the on / off operation of the third relay KA03. When the process chamber pressure exceeds a preset pressure threshold of 10 Torr, the PLC outputs a low level to the zero contact of the first relay KA01. At this point, the normally open contacts 13 and 14 of the first relay KA01 open, while the normally closed contacts 11 and 12 close. This causes the third relay KA03 to open, and the second relay KA02 to open. At this point, the KA02 relay controls the on / off operation of the circuit.

[0096] In one embodiment of the present invention, the second relay includes a second pair of normally closed contacts, a second pair of normally open contacts and a third pair of normally open contacts; the second pair of normally closed contacts is controlled by the second relay to remain in a closed state, and the first circuit is controlled to be connected; and the second relay is controlled by the second pair of normally open contacts and the third pair of normally open contacts to remain in an open state, and the second circuit and the third circuit are controlled to be disconnected, so that the first gas corresponding valve is closed and the second gas corresponding valve and the third gas corresponding valve are opened.

[0097] Exemplarily, the second relay may include a second pair of normally closed contacts, a second pair of normally open contacts, and a third pair of normally open contacts. When the process chamber pressure is greater than a preset pressure threshold, the first relay controls the second relay to be connected and the third relay to be disconnected. The second relay may control the second pair of normally closed contacts to remain closed, thereby connecting the first circuit, and control the second pair of normally open contacts and the third pair of normally open contacts to remain disconnected, thereby disconnecting the second circuit and the third circuit, thereby closing the first gas valve and opening the second and third gas valves.

[0098] In one embodiment of the present invention, the first gas is NF3, the second gas is H2, and the third gas is SiH4.

[0099] As an example, the first gas may be NF3, the second gas may be H2, and the third gas may be SiH4.

[0100] For example, Figure 2 The figure shows a schematic diagram of a special gas safety control principle provided by an embodiment of the present invention. The second relay KA02 includes a second pair of normally closed contacts 21 and 22, which can control the on-off of the NF3 valve by controlling the on-off of the first circuit; includes a second pair of normally open contacts 23 and 24, which can control the on-off of the H2 valve by controlling the on-off of the second circuit; and includes a third pair of normally open contacts 25 and 26, which can control the on-off of the SiH4 valve by controlling the on-off of the third circuit. When the process chamber pressure is greater than 10Torr, the KA02 relay controls the on / off of the circuit. When the H2 and SiH4 valves need to be opened, the PLC's NF3 and the H2 and SiH4 valve opening switching signals can output high-level signals. The KA02 relay receives the high-level signal and can control KA02's contacts 23, 24 and contacts 25, 26 to close, and contacts 21, 22 to disconnect. At this time, the circuits controlling the H2 and SiH4 valves are connected, and the circuit controlling the NF3 valve is disconnected. The H2 and SiH4 valves are allowed to open, and the NF3 valve is closed.

[0101] Step 103: When the valve corresponding to the first gas needs to be opened, the first circuit is controlled to be closed, and the second circuit and the third circuit are controlled to be disconnected, so that the valve corresponding to the first gas is opened and the valve corresponding to the second gas and the valve corresponding to the third gas are closed.

[0102] For example, if the pressure value of the process chamber is greater than a preset pressure threshold, when the first gas valve needs to be opened, the first circuit can be controlled to be closed, and the second circuit and the third circuit can be controlled to be disconnected, so that the first gas valve is opened and the second gas valve and the third gas valve are closed, thereby achieving the first gas valve and the second gas valve not being opened at the same time, and the first gas valve and the third gas valve not being opened at the same time.

[0103] In one embodiment of the present invention, the second pair of normally closed contacts is controlled by the second relay to remain in a closed state, controlling the first circuit to be connected, and the second pair of normally open contacts and the third pair of normally open contacts are controlled by the second relay to remain in an open state, controlling the second circuit and the third circuit to be disconnected, so that the valve corresponding to the first gas is opened and the valve corresponding to the second gas and the valve corresponding to the third gas are closed.

[0104] For example, when the second relay is turned on, when it is necessary to open the NF3 valve, the second relay can control the second pair of normally closed contacts to remain in a closed state to connect the first circuit, and control the second pair of normally open contacts and the third pair of normally open contacts to remain in an open state to disconnect the second circuit and the third circuit, thereby controlling the NF3 valve to open and the H2 valve and the SiH4 valve to close.

[0105] For example, when the KA02 relay is connected, when the NF3 valve needs to be opened, the PLC's NF3 and H2, SiH4 valve opening switching signals can output low-level signals. The KA02 relay receives the low-level signal and can control the normally open contacts 23, 24 and normally open contacts 25, 26 of KA02 to be disconnected, and the normally closed contacts 21, 22 to be closed. At this time, the circuit controlling the H2 valve and SiH4 valve is disconnected, and the circuit controlling the NF3 valve is connected, the H2 valve and SiH4 valve are closed, and the NF3 valve is allowed to open.

[0106] In one embodiment of the present invention, when the pressure value is less than or equal to the preset pressure threshold, the first circuit, the second circuit and the third circuit are controlled to be connected so that the first gas corresponding valve, the second gas corresponding valve and the third gas corresponding valve are opened.

[0107] For example, if the pressure value of the process chamber is less than or equal to the preset pressure threshold, it means that the concentration of the special gas in the process chamber is low, and the gas molecules are inactive and not prone to chemical reactions. No electrical interlocking is required, and the first circuit, the second circuit and the third circuit can be controlled to be connected to open the NF3 valve, the H2 valve and the SiH4 valve.

[0108] In one embodiment of the present invention, when the pressure value is less than or equal to the preset pressure threshold, the first pair of normally closed contacts are controlled to open and the second relay is controlled to disconnect through the first relay, and the first pair of normally open contacts are controlled to close and the third relay is controlled to connect through the first relay, so that the third relay controls the on and off of the first circuit, the second circuit and the third circuit.

[0109] For example, when the pressure value of the process chamber is less than or equal to a preset pressure threshold, the PLC can output a high-level signal to the first relay. The first relay receives the high-level signal and can control the first pair of normally closed contacts to open to disconnect the second relay, and control the first pair of normally open contacts to close to connect the third relay, thereby controlling the third relay to control the on and off of the first circuit, the second circuit and the third circuit.

[0110] For example, when the pressure value of the process chamber is less than or equal to 10 Torr, the PLC can output a high-level signal to the first relay KA01. KA01 receives the high-level signal and can control the normally closed contacts 11 and 12 to open, so that the second relay KA02 is disconnected, and control the normally open contacts 13 and 14 to close, so that the third relay KA03 is turned on. KA03 controls the on and off of the circuit.

[0111] In one embodiment of the present invention, the fourth pair of normally open contacts, the fifth pair of normally open contacts and the sixth pair of normally open contacts are controlled to be closed by the third relay, and the first circuit, the second circuit and the third circuit are controlled to be connected, so that the first gas corresponding valve, the second gas corresponding valve and the third gas corresponding valve are opened.

[0112] Illustratively, when the third relay is turned on, the third relay can control the fourth pair of normally open contacts, the fifth pair of normally open contacts and the sixth pair of normally open contacts to close, so that the first circuit, the second circuit and the third circuit are connected, thereby controlling the valves corresponding to NF3, H2 and SiH4 to open.

[0113] For example, Figure 2As shown is a schematic diagram of a special gas safety control principle provided by an embodiment of the present invention. The third relay KA03 includes a fourth pair of normally open contacts 31 and 32, which can control the on-off of the NF3 valve by controlling the on-off of the first circuit, includes a fifth pair of normally open contacts 33 and 34, which can control the on-off of the H2 valve by controlling the on-off of the second circuit, and includes a sixth pair of normally open contacts 35 and 36, which can control the on-off of the SiH4 valve by controlling the on-off of the third circuit.

[0114] When the process chamber pressure drops below 10 Torr, the PLC outputs a high-level signal to the zero contact of relay KA01. This closes normally-open contacts 13 and 14, while disconnecting normally-closed contacts 11 and 12. This prevents KA02 from receiving a high-level signal. KA02 then disconnects, and the zero contact of KA03 receives a 24V high-level signal. KA03 then controls the circuit. Relay KA03 closes its normally-open contacts 31, 32, 33, 34, and 35, 36, activating the signals to open the H2, NF3, and SiH4 valves, causing them to open. This ensures that the H2, NF3, and SiH4 valves are not electrically mutually exclusive when the chamber pressure is below 10 Torr.

[0115] In an embodiment of the present invention, a pressure value of the process chamber is obtained; when the pressure value is greater than a preset pressure threshold, when it is necessary to open the valve corresponding to the second gas and the valve corresponding to the third gas, the first circuit is controlled to be disconnected, and the second circuit and the third circuit are controlled to be connected, so that the valve corresponding to the first gas is closed and the valve corresponding to the second gas and the valve corresponding to the third gas are opened; when it is necessary to open the valve corresponding to the first gas, the first circuit is controlled to be closed, and the second circuit and the third circuit are controlled to be disconnected, so that the valve corresponding to the first gas is opened and the valve corresponding to the second gas and the valve corresponding to the third gas are closed. By incorporating valve interlocks into the circuit design, when the process chamber pressure reaches the preset threshold, the first and second gas valves and the first and third gas valves will not be opened simultaneously, thereby avoiding the risk of software control failure, preventing chemical reactions between the specialty gases from generating byproducts that could damage hardware and injure personnel, eliminating safety hazards, and protecting the safety of the system and personnel.

[0116] It should be noted that for the sake of simplicity, the method embodiments are described as a series of actions. However, those skilled in the art should be aware that the embodiments of the present invention are not limited by the order of the actions described, because according to the embodiments of the present invention, certain steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also be aware that the embodiments described in this specification are all preferred embodiments, and the actions involved are not necessarily required by the embodiments of the present invention.

[0117] Reference Figure 3 , shows a structural block diagram of a semiconductor process equipment provided by an embodiment of the present invention. The semiconductor process equipment 301 includes: a process chamber, a control circuit; the control circuit includes a first circuit for controlling the on / off of a valve corresponding to a first gas, a second circuit for controlling the on / off of a valve corresponding to a second gas, and a third circuit for controlling the on / off of a valve corresponding to a third gas. The semiconductor process equipment also includes:

[0118] The controller 3011 is used to obtain the pressure value of the above-mentioned process chamber; when the above-mentioned pressure value is greater than a preset pressure threshold, when it is necessary to open the above-mentioned second gas corresponding valve and the above-mentioned third gas corresponding valve, the first circuit is controlled to be disconnected, and the above-mentioned second circuit and the above-mentioned third circuit are controlled to be connected, so that the above-mentioned first gas corresponding valve is closed and the above-mentioned second gas corresponding valve and the above-mentioned third gas corresponding valve are opened; when it is necessary to open the above-mentioned first gas corresponding valve, the first circuit is controlled to be closed, and the above-mentioned second circuit and the above-mentioned third circuit are controlled to be disconnected, so that the above-mentioned first gas corresponding valve is opened and the above-mentioned second gas corresponding valve and the above-mentioned third gas corresponding valve are closed.

[0119] In an optional embodiment of the present invention, the controller is further configured to control the first circuit, the second circuit and the third circuit to be connected when the pressure value is less than or equal to a preset pressure threshold, so that the valve corresponding to the first gas, the valve corresponding to the second gas and the valve corresponding to the third gas are opened.

[0120] In an optional embodiment of the present invention, the above-mentioned circuit also includes: a first relay, a second relay and a third relay. The above-mentioned controller is also used to obtain the pressure value of the above-mentioned process chamber. When the above-mentioned pressure value is greater than a preset pressure threshold, the above-mentioned first relay controls the above-mentioned second relay to be connected and the above-mentioned third relay to be disconnected, so that the above-mentioned second relay controls the on and off of the above-mentioned first circuit, the above-mentioned second circuit and the above-mentioned third circuit; when the above-mentioned pressure value is less than or equal to the preset pressure threshold, the above-mentioned first relay controls the above-mentioned second relay to be disconnected and the above-mentioned third relay to be connected, so that the above-mentioned third relay controls the on and off of the above-mentioned first circuit, the above-mentioned second circuit and the above-mentioned third circuit.

[0121] In an optional embodiment of the present invention, the first relay includes a first pair of normally closed contacts and a first pair of normally open contacts; the controller is configured to control the first pair of normally open contacts to remain in an open state and control the third relay to be disconnected when the pressure value is greater than a preset pressure threshold, and to control the first pair of normally closed contacts to remain in a closed state and control the second relay to be connected, so that the second relay controls the on and off of the first circuit, the second circuit and the third circuit.

[0122] In an optional embodiment of the present invention, the second relay includes a second pair of normally closed contacts, a second pair of normally open contacts and a third pair of normally open contacts; the controller is used to control the second pair of normally closed contacts to be disconnected through the second relay, control the first circuit to be disconnected, and control the second pair of normally open contacts and the third pair of normally open contacts to be closed through the second relay, control the second circuit and the third circuit to be connected, so that the first gas corresponding valve is closed and the second gas corresponding valve and the third gas corresponding valve are opened.

[0123] In an optional embodiment of the present invention, the controller is configured to control the second pair of normally closed contacts to remain in a closed state through the second relay, control the first circuit to be connected, and control the second pair of normally open contacts and the third pair of normally open contacts to remain in an open state through the second relay, control the second circuit and the third circuit to be disconnected, so that the valve corresponding to the first gas is opened and the valve corresponding to the second gas and the valve corresponding to the third gas are closed.

[0124] In an optional embodiment of the present invention, the above-mentioned controller is used to control the above-mentioned first pair of normally closed contacts to open and the above-mentioned second relay to disconnect when the above-mentioned pressure value is less than or equal to a preset pressure threshold value, and to control the above-mentioned first pair of normally open contacts to close and the above-mentioned third relay to connect through the above-mentioned first relay, so that the above-mentioned third relay controls the on and off of the above-mentioned first circuit, the above-mentioned second circuit and the above-mentioned third circuit.

[0125] In an optional embodiment of the present invention, the above-mentioned third relay includes a fourth pair of normally open contacts, a fifth pair of normally open contacts and a sixth pair of normally open contacts; the above-mentioned controller is used to control the closure of the above-mentioned fourth pair of normally open contacts, the above-mentioned fifth pair of normally open contacts and the above-mentioned sixth pair of normally open contacts through the above-mentioned third relay, and control the above-mentioned first circuit, the above-mentioned second circuit and the above-mentioned third circuit to be connected, so that the above-mentioned first gas corresponding valve, the above-mentioned second gas corresponding valve and the above-mentioned third gas corresponding valve are opened.

[0126] In an optional embodiment of the present invention, the first gas is NF3, the second gas is H2, and the third gas is SiH4.

[0127] As for the device embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment.

[0128] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0129] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, apparatus, or computer program products. Thus, embodiments of the present invention may take the form of a fully hardware embodiment, a fully software embodiment, or an embodiment combining software and hardware. Furthermore, embodiments of the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0130] The embodiments of the present invention are described with reference to the flowcharts and / or block diagrams of the methods, terminal devices (systems), and computer program products according to the embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of the processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing terminal device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing terminal device generate instructions for implementing the process in the flowchart and / or block diagram. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0131] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing terminal device to operate in a specific manner, so that the instructions stored in the computer readable memory produce a manufactured product including an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0132] These computer program instructions can also be loaded onto a computer or other programmable data processing terminal device so that a series of operating steps are executed on the computer or other programmable terminal device to produce a computer-implemented process, thereby providing instructions for executing on the computer or other programmable terminal device to implement the process. Figure 1 a process or multiple processes and / or boxes Figure 1A step that specifies a function in one or more boxes.

[0133] Although the preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they become aware of the basic creative concepts. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the embodiments of the present invention.

[0134] Finally, it should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device that includes a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or terminal device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article, or terminal device that includes the element.

[0135] The above is a detailed introduction to a special gas safety control method and a semiconductor process equipment provided by the present invention. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. At the same time, for those skilled in the art, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scopes. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A special gas safety control device, characterized in that: Applicable to semiconductor process equipment, the semiconductor process equipment includes a process chamber; the control device includes an electrically connected control circuit and a controller; The control circuit comprises: A first circuit is used to control the on / off of a valve corresponding to the first gas; The second circuit is used to control the on / off of the valve corresponding to the second gas; A third circuit is used to control the on / off of a valve corresponding to a third gas; The controller is used to: Acquiring a pressure value signal of the process chamber; When the pressure value is greater than the preset pressure threshold, when it is necessary to open the second gas corresponding valve and the third gas corresponding valve, the first circuit is controlled to be disconnected, and the second circuit and the third circuit are controlled to be connected, so that the first gas corresponding valve is closed and the second gas corresponding valve and the third gas corresponding valve are opened; when it is necessary to open the first gas corresponding valve, the first circuit is controlled to be closed, and the second circuit and the third circuit are controlled to be disconnected, so that the first gas corresponding valve is opened and the second gas corresponding valve and the third gas corresponding valve are closed; so that when the pressure value of the process chamber is greater than the preset pressure threshold, the first gas corresponding valve and the second gas corresponding valve will not be opened at the same time, and the first gas corresponding valve and the third gas corresponding valve will not be opened at the same time, so as to prevent a chemical reaction between the first gas, the second gas and the third gas from generating by-products.

2. The control device according to claim 1, characterized in that The controller is also used to: when the pressure value is less than or equal to the preset pressure threshold, control the first circuit, the second circuit and the third circuit to be connected, so that the first gas corresponding valve, the second gas corresponding valve and the third gas corresponding valve are opened.

3. The control device according to claim 2, characterized in that The control circuit further includes: a first relay, a second relay, and a third relay; the first relay is electrically connected to the second relay and the third relay respectively; the controller is configured to: When the pressure value is greater than the preset pressure threshold, the first relay is controlled to turn on the second relay and turn off the third relay, so that the second relay controls the on and off of the first circuit, the second circuit, and the third circuit; When the pressure value is less than or equal to the preset pressure threshold, the first relay is controlled to disconnect the second relay and connect the third relay, so that the third relay controls the on and off of the first circuit, the second circuit, and the third circuit.

4. The control device according to claim 3, characterized in that The first relay includes a first pair of normally closed contacts and a first pair of normally open contacts; The first pair of normally open contacts is electrically connected to the third relay, and the first pair of normally closed contacts is electrically connected to the second relay; the controller is specifically configured to: When the pressure value is greater than the preset pressure threshold, the first pair of normally open contacts are controlled to remain in an open state, so as to control the third relay to be disconnected; the first pair of normally closed contacts are controlled to remain in a closed state, so as to control the second relay to be connected, so that the second relay controls the on and off of the first circuit, the second circuit, and the third circuit; When the pressure value is less than or equal to the preset pressure threshold: control the first pair of normally open contacts to remain in a closed state to control the third relay to be turned on, so that the third relay controls the on and off of the first circuit, the second circuit and the third circuit; control the first pair of normally closed contacts to remain in an open state to control the second relay to be turned off.

5. The control device according to claim 4, characterized in that The second relay includes a second pair of normally closed contacts, a second pair of normally open contacts, and a third pair of normally open contacts; The second pair of normally closed contacts is electrically connected to the first circuit, the second pair of normally open contacts is connected to the second circuit, and the third pair of normally open contacts is connected to the third circuit; the controller is specifically configured to: When the pressure value is greater than the preset pressure threshold, when it is necessary to open the second gas corresponding valve and the third gas corresponding valve: the second pair of normally closed contacts are controlled to remain in an open state, so as to control the first circuit to be disconnected, so that the first gas corresponding valve is closed; the second pair of normally open contacts are controlled to remain in a closed state, so as to control the second circuit to be connected, so that the second gas corresponding valve is opened; and the third pair of normally open contacts are controlled to remain in a closed state, so as to control the third circuit to be connected, so that the third gas corresponding valve is opened; When the pressure value is greater than the preset pressure threshold, when it is necessary to open the valve corresponding to the first gas: the second pair of normally closed contacts are controlled to remain in a closed state to control the first circuit to be connected, so that the valve corresponding to the first gas is opened; the second pair of normally open contacts are controlled to remain in an open state to control the second circuit to be disconnected, so that the valve corresponding to the second gas is closed; the third pair of normally open contacts are controlled to remain in an open state to control the third circuit to be disconnected, so that the valve corresponding to the third gas is closed.

6. The control device according to claim 4, characterized in that The third relay includes a fourth pair of normally open contacts, a fifth pair of normally open contacts and a sixth pair of normally open contacts; The fourth pair of normally open contacts is electrically connected to the first circuit, the fifth pair of normally open contacts is electrically connected to the second circuit, and the sixth pair of normally open contacts is electrically connected to the third circuit; the controller is specifically configured to: When the pressure value is less than or equal to the preset pressure threshold: the fourth pair of normally open contacts is controlled to remain in a closed state to control the first circuit to be connected, so that the valve corresponding to the first gas is opened; the fifth pair of normally open contacts is controlled to remain in a closed state to control the second circuit to be connected, so that the valve corresponding to the second gas is opened; the sixth pair of normally open contacts is controlled to remain in a closed state to control the third circuit to be connected, so that the valve corresponding to the third gas is opened.

7. The control device according to claim 1, characterized in that The first gas is NF3, the second gas is H2, and the third gas is SiH4.

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