ABATEMENT WATER FLOW CONTROL SYSTEM AND OPERATION METHOD THEREOF

A system including a water flow controller arranged to transmit electrical signals between a fluoride ion clean tool and a fluoride emission abatement system is provided. Fluoride gas is configured to be released from the fluoride ion clean tool and lead to the fluoride emission abatement system, and water is introduced to the fluoride emission abatement system so as to process the fluoride gas. The water flow controller further includes a receiver for accepting electrical signals from a detector. The detector is configured to measure a flow rate of fluoride gas introduced to the fluoride ion clean tool. In addition, a computing unit is configured to process electrical signals from the detector. A transmitter is configured to send commands to an actuator of the fluoride emission abatement system so as to adjust water introduced to the fluoride emission abatement system based on a processing result of the computing unit.

FIELD

The present disclosure relates to an abatement water flow control system and operation method thereof.

BACKGROUND

In the semiconductor production industry, various processing steps are used to fabricate integrated circuits on a semiconductor wafer. These steps include the deposition of layers of different materials including metallization layers, passivation layers and insulation layers on the wafer substrate, as well as photoresist stripping and sidewall passivation polymer layer removal. In modern memory devices, for example, multiple layers of metal conductors are required for providing a multi-layer metal interconnection structure in defining a circuit on the wafer. Chemical vapor deposition (CVD) processes are widely used to form layers of materials on a semiconductor wafer.

CVD processes include thermal deposition processes, in which a gas is reacted with the heated surface of a semiconductor wafer substrate, as well as plasma-enhanced CVD processes, in which a gas is subjected to electromagnetic energy in order to transform the gas into a more reactive plasma. However, in plasma process chambers used to carry out these various CVD processes, materials such as polymers are coated onto the chamber walls and other interior chamber components and surfaces during the processes. These polymer coatings frequently generate particles which inadvertently become dislodged from the surfaces and contaminate the wafers.

To remove the residue materials from the chamber walls, cleaning gases, such as fluorocarcon gases, are used. During the cleaning process, the F ions will be recomposed into F2, SiF4, COF2 or other fluoride compounds. However, fluoride compounds are known pollutants. For example, fluoride compounds diffuse undesirable odor. Moreover, fluoride compounds exert a considerable global warming potential (GWP) effect on the environment. Increasingly, governments and international treaties are requiring that the venting of high-GWP chemicals be reduced or eliminated. Measures to reduce fluoride compound contaminations on the environment are continuously being sought.

DETAILED DESCRIPTION OF THE DISCLOSURE

Throughout the various views and illustrative embodiments, like reference numerals are used to designate like elements. Reference will now be made in detail to exemplary embodiments illustrated in the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the description to refer to the same or like parts. In the drawings, the shape and thickness may be exaggerated for clarity and convenience. This description will be directed in particular to elements forming part of, or cooperating more directly with, an apparatus in accordance with the present disclosure. It is to be understood that elements not specifically shown or described may take various forms. Reference throughout this specification to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, the appearances of the phrases “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. It should be appreciated that the following figures are not drawn to scale; rather, these figures are merely intended for illustration.

In the drawings, like reference numbers are used to designate like or similar elements throughout the various views, and illustrative embodiments of the present disclosure are shown and described. The figures are not necessarily drawn to scale, and in some instances the drawings have been exaggerated and/or simplified in places for illustrative purposes. One of ordinary skill in the art will appreciate the many possible applications and variations of the present disclosure based on the following illustrative embodiments of the present disclosure.

It will be understood that singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. Furthermore, relative terms, such as “bottom” and “top,” may be used herein to describe one element's relationship to other elements as illustrated in the Figures.

It will be understood that elements described as “under” or “below” other elements would then be oriented “over” or “above” the other elements. The exemplary terms “under” or “below” can, therefore, encompass both an orientation of over and under.

FIG. 1is a system including a water flow controller in accordance with some embodiments of the present disclosure.

Referring toFIG. 1, a system10including a water flow controller100is provided. In some embodiments, the system10is a semiconductor wafer process system. In certain embodiments, the system10is an integrated circuit process system, a liquid-crystal display process system or a light-emitting diode process system. The water flow controller100is configured to adjust water distribution in the system10for numerous processes. For example, water is introduced to the system10for a chemical vapor deposition (CVD) process. Alternatively, the water flow controller100is applicable in processes used in the fabrication of integrated circuits or semiconductor wafer substrates.

In some embodiments in accordance with the present disclosure, the water flow controller100has a receiver102connected with a computing unit104. In addition, the computing unit104is connected with a transmitter106. The receiver102accepts electrical signals from a sensor or detector wirelessly or through a physical interface. The signals indicate an operation condition of the system10. The computing unit104receives the electrical signals from the receiver102and processes such electrical signals. For example, the computing unit104extracts a value from the electrical signal and compares such value with a predetermined value. Based on the comparison result, the computing unit104sends a command to another device in the system100through the transmitter106wirelessly or through a physical interface. In some embodiments, the command sent by the computing unit104serves to adjust water distribution in the system10.

In some embodiments in accordance with the present disclosure, the computing unit104is a general purpose microprocessor known in the art. For example, the computing unit104includes an application-specific integrated circuit (ASIC), reduced instruction set processor (RISC), or programmable logic controller (PLC). In another example, the computing unit104is a central processing unit (CPU) or a microprocessor.

In some embodiments in accordance with the present disclosure, the system10includes a fluoride ion clean tool200connected with a fluoride emission abatement system300through a foreline202. In certain embodiments, the fluoride ion clean tool200includes a chemical vapor deposition (CVD) process chamber. During normal operation of the fluoride ion clean tool200, material residues gradually accumulate on the interior surfaces of the fluoride ion clean tool200. The material residues include silicon nitride and silicon dioxide, for example. Particles from the residues have a tendency to break off and potentially contaminate devices being fabricated on subsequent wafers processed in the fluoride ion clean tool200. Accordingly, the particles are arranged to be periodically removed from the interior surfaces of the fluoride ion clean tool200for optimum processing. During clean operation of the fluoride ion clean tool200, fluoride compound gas (alternatively “fluoride gas”), or fluoride ion is introduced to the fluoride ion clean tool200to react with the particles. Exhaust fluoride gas, such as F2, NF3, C2F6, SiF4 or the like, is generated and lead to the fluoride emission abatement system300through the foreline202. Water is provided at the fluoride emission abatement system300to react with the exhaust fluoride gas so as to reduce the amount of fluoride compound being released to the environment.

In some embodiments in accordance with the present disclosure, the fluoride ion clean tool200is connected with a gas source204for containing fluoride gas to be introduced to the fluoride ion clean tool200. A valve206is arranged between the fluoride ion clean tool200and the gas source204to control the fluoride gas output flow. In some embodiments, the fluoride gas includes F2, NF3, C2F6 or SiF4. In certain embodiments, an actuator of the valve206is connected to a central control unit (not depicted) of the system10. Accordingly, the valve is configurable by the central control unit depending on the condition of the system10. For example, the amount of fluoride gas introduced to the fluoride ion clean tool200is adjusted based on the condition of the system10.

In some embodiments in accordance with the present disclosure, the fluoride ion clean tool200is or is part of a semiconductor wafer process tool, an integrated circuit process tool, a liquid-crystal display process tool or a light-emitting diode process tool.

In some embodiments in accordance with the present disclosure, a pump208is arranged between the fluoride ion clean tool200and the fluoride emission abatement system300. The pump208serves to provide a suction force to lead fluoride gas out of the fluoride ion clean tool200and into the fluoride emission abatement system300. In some embodiments, the pump208continues to generate a suction force. In certain embodiments, the pump208is equipped with an actuator, and the actuator is configured to receive commands from the central control unit of the system10. Accordingly, the suction force generated by the pump208is adjustable based on the condition of the system10. In some embodiments, the pump208is a dry pump.

In some embodiments in accordance with the present disclosure, the fluoride emission abatement system300is connected with a water source302. Water (H2O) is provided from the water source302through a valve304to the fluoride emission abatement system300. In certain embodiments, water is used to interact with fluoride gas so as to turn fluoride gas into liquid HF. Accordingly, the amount of fluoride gas released to the environment is lessened. In some embodiments, water is introduced to the fluoride emission abatement system300continuously. In certain embodiments, the fluoride emission abatement system300is a scrubber.

In some embodiments in accordance with the present disclosure, the amount of water introduced to the fluoride emission abatement system300is adjustable by the valve304. The valve is equipped with an actuator306. The actuator306is configured to receive commands, which are based on the processing result of the computing unit104, from the transmitter106of the water flow controller100. Depending on the operation condition of the system10or the fabrication plant facilitating the system10, the computing unit104sends out different commands to the actuator306so as to adjust the valve304.

In some embodiments in accordance with the present disclosure, electrical signals are transmitted between the fluoride ion clean tool200and the fluoride emission abatement system300through the water flow controller100. For example, signal of the processing status of the fluoride ion clean tool200is transmitted to the water flow controller100. After processing the signal, the water flow controller100sends a command to the fluoride emission abatement system300. Accordingly, the fluoride emission abatement system300adjusts its processing status in response to the command from the water flow controller100. In certain embodiments, when the fluoride ion clean tool200is in normal operation, the fluoride emission abatement system300reduces its processing rate due to the lessened output of fluoride gas from the fluoride ion clean tool200.

In some embodiments in accordance with the present disclosure, a detector210is provided in the system10. The detector210is configured to measure a flow rate of fluoride compound, such as the fluoride gas, introduced to the fluoride ion clean tool200. Thereafter, the detector210sends electronic signals containing the information of the flow rate to the receiver102. The computing unit104is configured to process such electronic signals received from the detector210. For example, the computing unit104compares the flow rate with a predetermined value. If the flow rate is above the predetermined value, the computing unit104determines that the fluoride ion clean tool200is in a clean operation. A command to increase water introduction is generated and sent through the transmitter106to the actuator306. Accordingly, the actuator306adjusts the valve304so as to increase water introduction to the fluoride emission abatement system300. The increased amount of water reduces the chance of fluoride gas being released to the environment.

In some embodiments in accordance with the present disclosure, when the fluoride gas is being introduced to the fluoride ion clean tool200at a first flow rate, the water flow controller100adjusts the water introduction to the fluoride emission abatement system300at a first water flow rate. In addition, when the fluoride gas is being introduced to the fluoride ion clean tool200at a second flow rate, the water flow controller100adjusts the water introduction to the fluoride emission abatement system300at a second water flow rate. When the first flow rate is higher than the second flow rate, the first water flow rate is higher than the second water flow rate. In other words, when fluoride gas is introduced to the fluoride ion clean tool200at a higher flow rate, i.e., when the fluoride ion clean tool200is in the clean operation, more water is introduced to the fluoride emission abatement system300to process the fluoride gas. Contrarily, when fluoride gas is introduced to the fluoride ion clean tool200at a lower velocity, i.e., when the fluoride ion clean tool200is in the normal operation, less water is needed at the fluoride emission abatement system300. In certain embodiments, water is introduced to the fluoride emission abatement system300at a flow rate between about 8 LPM (liter per minute) and about 12 LPM when the when the fluoride ion clean tool200is in the clean operation. In addition, water is introduced to the fluoride emission abatement system300at a flow rate between about 0 LPM and about 5 LPM when the when the fluoride ion clean tool200is in the normal operation.

In some embodiments in accordance with the present disclosure, the detector210is disposed between the gas source204and the fluoride ion clean tool200. For example, the detector210is disposed at the valve206. Alternatively, the detector210is disposed at the pump208, the foreline202, or the fluoride ion clean tool200itself. In certain embodiments, the detector is a flow meter at the fluoride emission abatement system300so as to detect the flow rate of fluoride gas introduced to the fluoride emission abatement system300.

FIGS. 2A to 2Care systems including a water flow controller in accordance with some embodiments of the present disclosure.

Referring toFIG. 2A, in some embodiments, the water flow controller100is configured to receive electrical signals from a central control unit400of the fabrication plant facilitating the system10. Alternatively, the water flow controller100is connected with a central control unit400so as to receive the signal. The signal transmitted from the central control unit400contains the condition of the fabrication plant, or processing status of other process tools within the fabrication plant. An exemplary process tool is a semiconductor wafer processing tool. The computing unit104of the water flow controller100receives the signal via the receiver102and processes the signal. Depending on the conditions transmitted, the computing unit104generates commands to be transmitted to the actuator306through the transmitter106. Accordingly, water introduction to the fluoride emission abatement system300is manipulated based on the commands. For example, when another process tool in the fabrication plant requests more water, water introduction to the fluoride emission abatement system300is lessened. In certain embodiments, in response to the water decrease, the water flow controller100is configured to send a command to a mass flow controller (MFC) of the fluoride ion clean tool200so as to reduce fluoride gas from being introduced to the fluoride ion clean tool200.

In some embodiments in accordance with the present disclosure, the central control unit400is a manufacturing execution system (MES) at the fabrication plant. The manufacturing execution system monitors all the operations in fabrication plants, and relays messages to the sub-control systems, such as system10, to maintain smooth cooperation between systems.

In some embodiments in accordance with the present disclosure, the fluoride emission abatement system300is connected with a waste processor308. The waste processor308receives exhaust fluoride compound and/or exhaust water from the fluoride emission abatement system300and performs further processing. For example, the waste processor separates the exhaust fluoride compound and the exhaust water and outputs them to the environment through different forelines3082,3084to reduce contamination. In some embodiments, the waste processor308has a detector310. The detector310measures the concentration of fluoride compound at the waste processor308and transmits such information in the form of electrical signal to the receiver102. The processor104compares such concentration with a predetermined value and determines whether a specific event has occurred. For example, a concentration of fluoride compound over a predetermined value indicates that the fluoride ion clean tool200is in a clean operation. Accordingly, the processor104sends a command to the actuator306through the transmitter106to adjust water introduction to the fluoride emission abatement system300. In certain embodiments, water introduction to the fluoride emission abatement system300is increased when the fluoride ion clean tool200is in a clean operation. In some embodiments, water introduction to the fluoride emission abatement system300is decreased when the fluoride ion clean tool200is in an idle mode.

In some embodiments in accordance with the present disclosure, water introduction to the fluoride emission abatement system300is adjusted according to a gas flow rate detected at the waste processor308. For example, the detector310is a flow meter for detecting fluoride compound gas flow rate at the waste processor308. The flow rate information is transmitted to the processor104and compared with a predetermined value. In certain embodiments, if the fluoride compound gas flow rate is below a predetermined value, the processor104sends a command to the actuator306through the transmitter106and decreases water introduction to the fluoride emission abatement system300.

Referring toFIG. 2B, in some embodiments, the system10includes a sensor for detecting ambient condition in the system10. For example, the sensor312is a pressure sensor arranged at the fluoride emission abatement system300. The sensor312detects a pressure in the fluoride emission abatement system300and transmits such information to the water flow controller100. The processor104receives such information through the receiver102. A processing result is acquired to be used to control the actuator306so as to manipulate the valve304. Accordingly, water introduction to the fluoride emission abatement system300is adjusted based on the pressure in the fluoride emission abatement system300. In some embodiments, a higher pressure in the fluoride emission abatement system300indicates that that the fluoride ion clean tool200is in the clean mode. Therefore, more water is introduced to the fluoride emission abatement system300to process the fluoride gas.

In some embodiments in accordance with the present disclosure, the sensor212is a chemical sensor arranged at the fluoride ion clean tool200. The sensor212detects concentration of fluoride gas at the fluoride ion clean tool200. The fluoride gas includes, but is not limited to, F2, NF3, C2F6, and SiF4. The sensor212transmits the detected concentration information to the processor104through the receiver102. The processor104compares the concentration with a predetermined value to determine the operation mode of the fluoride ion clean tool200. Based on the processing result, the actuator306of the valve304is manipulated so as to adjust water introduction to the fluoride emission abatement system300. In certain embodiments, when concentration of fluoride gas detected at the fluoride ion clean tool200is over about 1.0 ppm., the water flow controller100increases water introduction to the fluoride emission abatement system300so as to reduce fluoride compound contamination on the environment.

In some embodiments in accordance with the present disclosure, the sensor314is a fluoride concentration sensor arranged at the foreline202. The sensor314is configured to detect concentration of fluoride gas released from the fluoride ion clean tool200. The concentration is transmitted to the water flow controller100for processing. Based on the processing result, the water introduction to the fluoride emission abatement system300is adjusted. For example, if the fluoride concentration at the foreline202is over a predetermined value, the computing unit104determines that the fluoride ion clean tool200is in clean operation. Accordingly, more water is allowed to the fluoride emission abatement system300to process the excess fluoride gas from the fluoride ion clean tool200.

In some embodiments in accordance with the present disclosure, the water flow controller100is arranged at the fluoride emission abatement system300, as depicted inFIG. 2B. In certain embodiments, the water flow controller100is arranged at the fluoride ion clean tool200, as depicted inFIG. 2C. Alternatively, the water flow controller100is arranged at any position in the system10deemed reasonable to persons having ordinary skill in the art.

Referring toFIG. 2C, in some embodiments, the water flow controller100is arranged at the fluoride ion clean tool200. The controller100receives electrical signals with ambient condition at the fluoride ion clean tool200from the sensor212and processes such ambient condition by the processor104. The transmitter106sends the processing result to an actuator306of a valve304so as to adjust water introduction to the fluoride emission abatement system300. In certain embodiments, the system10has a first valve304and a second valve304′. Water is introduced continuously to the fluoride emission abatement system300through the second valve304′. On the other hand, the first valve304is manipulated by the water flow controller100so as to adjust water introduction through the first valve304. For example, when the fluoride ion clean tool200is in a clean mode, more water is needed to process the excessive fluoride gas at the fluoride emission abatement system300. Therefore, water is allowed to flow through both the first valve304and the second valve304′. On the other hand, when the fluoride ion clean tool200is in normal operation, less water is needed to process the fluoride gas at the fluoride emission abatement system300. Therefore, water is not allowed to flow through the first valve304. Accordingly, water introduction to the fluoride emission abatement system300is controlled based on the processing status of the fluoride ion clean tool200. In certain embodiments, the valves304,304′ can be adjusted manually. For example, a processing status of the fluoride ion clean tool200is displayed at a panel of the fluoride ion clean tool200or the water flow controller100. Based on the information displayed, technicians of the fabrication plant adjust the valve304,304′ to manipulate water introduction to the fluoride emission abatement system300. In some embodiments, the valves304,304′ are on/off valves, which are easier for technicians to operate.

FIG. 3illustrates communications between components in a system including a water flow controller in accordance with some embodiments of the present disclosure.

Referring toFIG. 3, the detector210/sensor212,312,314continue to detect a processing status of the fluoride ion clean tool or an ambient condition in the system10(collectively the “operation information”). In step S102, the operation information is transmitted to the receiver102. In step S104, the operation information is transmitted to the computing unit104. Accordingly, the computing unit104processes the operation information and compares the operation information with some predetermined values, such as, fluoride compound gas concentration, pressure or flow rate. If the processing result indicates that the processing status of the fluoride ion clean tool is not changed, the computing unit104ignores the latest operation information and continues to process the next one. If the processing result indicates that the processing status of the fluoride ion clean tool is changed, for example, from a normal operation to a clean operation, in operation S106, the computing unit104sends a command to the transmitter106. In operation S108, The transmitter106relays the command to the actuator306. As a result, the water flow controller manipulates water introduction to the fluoride ion clean tool based on the processing status of the fluoride ion clean tool.

In some embodiments in accordance with the present disclosure, operations S102and S104are repeated continuously. In other words, latest operation information continues to be sent to the computing unit104through the receiver102. The computing unit104does not send out commands to adjust the actuator306until the computing unit104determines that a processing status of the fluoride ion clean tool has changed. For example, when the computing unit104determines that the fluoride ion clean tool has changed from a clean operation to a normal operation, in operation S106′, a command to adjust the actuator306is sent through the transmitter106. In operation S108′, the command to reduce the water flow rate running through the valve is transmitted to the actuator306. Accordingly, the water flow controller reduces water introduction to the fluoride emission abatement system based on the operation information of the fluoride ion clean tool.

In some embodiments in accordance with the present disclosure, the processing status of the fluoride ion clean tool is not limited to normal operation and clean operation. For example, the fluoride ion clean tool further has an idle mode, during which no operation is performed at the fluoride ion clean tool. In certain embodiments, the water flow controller is configured to provide different kinds of configuration in response to different processing statuses of the fluoride ion clean tool.

FIG. 4is a flow diagram of a method for manufacturing semiconductor wafer in accordance with some embodiments of the present disclosure.

Referring toFIG. 4, in operation S202, fluoride gas is provided at the fluoride ion clean tool to conduct a clean operation. In operation S204, the fluoride gas is lead out from the fluoride ion clean tool and to a fluoride emission abatement system. In operation S206, water is introduced to the fluoride emission abatement system so as to process the fluoride gas. In some embodiments, after the fluoride gas is processed, liquid HF is generated. In operation S208, a status of the clean operation of the fluoride ion clean tool is detected. In operation S210, based on the status of the clean operation, water introduction to the fluoride emission abatement system is manipulated. In certain embodiments, when the fluoride ion clean tool is in the clean operation, i.e., when more fluoride gas is introduced to the fluoride ion clean tool, more water is provided to the fluoride emission abatement system to process the excess fluoride gas. The various operations ofFIG. 4are discussed below in more detail in association with behavioral views corresponding to the operations of the flow diagram.

FIGS. 5A to 5Dare behavioral views of an apparatus in various stages corresponding to the method ofFIG. 4.

InFIG. 5A, the fluoride ion clean tool200is in normal operation. In some embodiments, the fluoride ion clean tool200is a chemical vapor deposition (CVD) tool at this stage. No or only little fluoride gas is introduced to the fluoride ion clean tool200. In addition, only little water is introduced to the fluoride emission abatement system300for purposes of cooling, maintaining steam concentration or others. Processing status of the fluoride ion clean tool200is transmitted in the form of electronic signals from the detector210or other detectors to the water flow processor100. Alternatively, flow rate of the fluoride gas is recorded as an indicator of the processing status of the fluoride ion clean tool200. In certain embodiments, water introduction to the fluoride emission abatement system300is maintained at a certain flow rate when the processing status of the fluoride ion clean tool200is not changed.

InFIG. 5B, the fluoride ion clean tool200is in clean operation. In other words, fluoride gas is introduced to the fluoride ion clean tool200from the gas source204through the valve206. A detector captures the status of the clean operation of the fluoride ion clean tool200and sends an electrical signal to the water flow controller100. Alternatively, the detector210captures a flow rate of fluoride gas introduced to the fluoride ion clean tool200and transmits such information to the water flow controller100. The computing unit104of the water flow controller100processes the electrical signal and generates a result. Based on the result, a command is sent to the actuator306of the valve304. Accordingly, the valve is opened and water is introduced to the fluoride emission abatement system300at a certain flow rate. In certain embodiments, the water flow controller100is configured to provide more water to the fluoride emission abatement system300right after the status of the clean operation is changed. In other words, water is pre-introduced to the fluoride emission abatement system300awaiting fluoride gas from the fluoride ion clean tool200.

In some embodiments in accordance with the present disclosure, ambient condition in the system10is detected to be used as water adjustment bases for the water flow controller100. For example, ambient condition at the fluoride ion clean tool200or the fluoride emission abatement system300is detected by a sensor (not depicted). In some embodiments, the sensor is a chemical sensor for detecting fluoride gas concentration at the fluoride ion clean tool200. A fluoride concentration over a predetermined value indicates that the fluoride ion clean tool200is in clean operation. The computing unit104generates a processing result and sends a command to the actuator306through the transmitter106. Accordingly, the water flow controller100adjusts the actuator306and allows more water to be introduced to the fluoride emission abatement system300. In certain embodiments, the sensor is a flow meter for detecting flow rate of fluoride gas introduced to the fluoride emission abatement system300. A flow rate lower than a predetermined value indicates that the fluoride ion clean tool200is not in clean operation. Accordingly, the water flow controller100adjusts the actuator306and reduces water introduction to the fluoride emission abatement system300.

InFIG. 5C, the fluoride ion clean tool200continues to be cleaned. In addition, the fluoride gas lead out of the fluoride ion clean tool200has reached the fluoride emission abatement system300. Because water has been pre-introduced to the fluoride emission abatement system300, fluoride gas are more thoroughly processed by and reacted with water. Accordingly, less fluoride compounds, such as F2, NF3, C2F6 or SiF4, will be released to the environment. In some embodiments, the water flow controller100continues to receive electrical signals from the detector210or other sensors. Accordingly, the water flow controller100determines whether the status of the clean operation of the fluoride ion clean tool200maintains the same. If so, the flow rate of water introduction to the fluoride emission abatement system300will be maintained.

InFIG. 5D, fluoride gas introduction to the fluoride ion clean tool200is reduced to little or zero. In other words, the fluoride ion clean tool200is now not in the clean operation. Electrical signals representing processing status of the fluoride ion clean tool200is transmitted to the water flow controller100from the sensor210or other detectors. After the computing unit104determines that the processing status of the fluoride ion clean tool200has changed, water introduction to the fluoride emission abatement system300is adjusted. In certain embodiments, the flow rate of water introduction to the fluoride emission abatement system300is maintained for a specific period to ensure that residue fluoride gas from the fluoride ion clean tool200are fully processed.

In some embodiments in accordance with the present disclosure, a processing status of one or more semiconductor wafer process tools or stages in the same fabrication plant is transmitted to the water flow controller100. Based on such information, the water flow controller100manipulates water introduction to the fluoride emission abatement system300. For example, when one semiconductor wafer process tool or stage in the same fabrication plant is in a water-poor condition (i.e. requires more water), the water flow controller100reduces water introduction to the fluoride emission abatement system300to accommodate such needs. In certain embodiments, the water flow controller100transmits the water-poor condition to the fluoride ion clean tool200. Accordingly, the fluoride ion clean tool200will not enter into the clean operation due to the insufficient amount of water available at the water source302.

In some embodiments, a system includes a fluoride ion clean tool connected with a fluoride emission abatement system through a foreline is provided. The system further includes a water flow controller arranged to transmit electrical signals between the fluoride ion clean tool and the fluoride emission abatement system. Fluoride gas is introduced to the fluoride ion clean tool for clean process. Thereafter, fluoride gas is released from the fluoride ion clean tool and lead to the fluoride emission abatement system. In addition, water is introduced to the fluoride emission abatement system so as to process the fluoride gas. The water-processed fluoride compound poses less contamination on the environment.

In some embodiments, the water flow controller includes a receiver connected with a computing unit. The receiver accepts electrical signals from a detector in the system. The detector in configured to measure a flow rate of fluoride gas introduced to the fluoride ion clean tool. The computing unit processes the electrical signals to reach a result. Based on the processing result of the computing unit, a transmitter sends commends to an actuator of the fluoride emission abatement system so as to adjust water introduced to the fluoride emission abatement system.

In some embodiments, the fluoride ion clean tool is part of a semiconductor wafer process tool, an integrated circuit process tool, a liquid-crystal display process tool or a light-emitting diode process tool.

In some embodiments, the water flow controller manipulates water introduction to the fluoride emission abatement system at a first water flow rate when fluoride gas is introduced to the fluoride ion clean tool at a first flow rate. In addition, the water flow controller manipulates water introduction to the fluoride emission abatement system at a second water flow rate when fluoride gas is introduced to the fluoride ion clean tool at a second flow rate. When the first flow rate is higher than the second flow rate, the first water flow rate is higher than the second water flow rate. In certain embodiments, the first water flow rate is between 8 LPM and about 12 LPM, and the second water flow rate is between about 0 and about 5 LPM.

In some embodiments, when the flow rate of fluoride gas introduced to the fluoride ion clean tool is above a predetermined value, the water flow controller increases water introduction to the fluoride emission abatement system.

In some embodiments, the water flow controller is connected with a central control unit of a fabrication plant facilitating the system. The water flow controller receives from the central control unit a signal of processing status of semiconductor wafer processing tools within the fabrication plant. In certain embodiments, the water flow controller manipulates water introduction to the fluoride emission abatement system according to the signal transmitted from the central control unit.

In some embodiments, the detector is a flow meter arranged at the fluoride emission abatement system for measuring a flow rate of fluoride compound at the fluoride emission abatement system.

In some embodiments, the water flow controller is connected with a sensor. The sensor detects an ambient condition in the system and transmits the ambient condition to the water flow controller. Based on the ambient condition, the water flow controller manipulates water introduction to the fluoride emission abatement system. In certain embodiments, the sensor is a pressure sensor for detecting a pressure in the fluoride emission abatement system.

In some embodiments, the sensor is a chemical sensor for detecting concentration of fluoride gas in the fluoride ion clean tool. In certain embodiments, the fluoride gas includes F2, NF3, C2F6 or SiF4. In some embodiments, the water flow controller increases the water introduction to the fluoride emission abatement system when concentration of the fluoride gas is over about 1.0 ppm.

In some embodiments, a system having a fluoride ion clean tool connected with a fluoride emission abatement system through a foreline is provided. Fluoride gas is used at the fluoride ion clean tool for cleaning, and released to the fluoride emission abatement system. Water is introduced to the fluoride emission abatement system from a water source so as to process the fluoride gas. The fluoride emission abatement system is connected with a waste processor, and fluoride gas released from the fluoride ion clean tool is lead to the waste processor after being processed by the fluoride emission abatement system.

In some embodiments, a water flow controller is provided at the system. The water flow controller is connected with an actuator, which is configured to control water introduction from the water source to the fluoride emission abatement system. The water flow controller includes a receiver for accepting electrical signals from a detector. The detector is arranged to measure a concentration of fluoride compound at the waste processor. In addition, a computing unit is arranged to process the electrical signals from the detector to reach a result. Based on the processing result of the computing unit, a transmitter sends commends to the actuator so as to adjust water introduced to the fluoride emission abatement system.

In some embodiments, the fluoride ion clean tool includes a chemical vapor deposition (CVD) process chamber.

In some embodiments, the water flow controller is arranged to adjust water introduction to the fluoride emission abatement system based on a gas flow rate detected at the waste processor.

In some embodiments, a method for manufacturing semiconductor wafer is provided. A clean operating at a fluoride ion clean tool is conducted by providing fluoride gas to the fluoride ion clean tool. The fluoride gas is lead from the fluoride ion clean tool to a fluoride emission abatement system. Water is introduced to the fluoride emission abatement system so as to process the fluoride gas. Status of the clean operation of the fluoride ion clean tool is detected. Based on the status of the clean operation, water introduction to the fluoride emission abatement system is adjusted.

In some embodiments, an ambient condition at the fluoride ion clean tool is detected. In certain embodiments, the ambient condition is compared with a predetermined value, and a comparison result is generated accordingly. Based on the comparison result, water introduction to the fluoride emission abatement system is manipulated.

In some embodiments, a processing status from a different semiconductor wafer process system is received. Based on the processing status of the different semiconductor wafer process system, water introduction to the fluoride emission abatement system is manipulated.