System and method for controlling foreline pressure

Abstract

Disclosed herein is a system and method for controlling pressure in a foreline of a processing system that reduces variations in foreline pressure. In one example, a processing system is provided that includes a first process chamber, a first pump, a foreline, and a first foreline pressure control system. The first pump has an inlet and an outlet. An inlet of the first pump is coupled to a discharge port of the first process chamber. The foreline is coupled to an outlet of the first pump. A first foreline pressure control system is fluidly coupled to the foreline downstream of the first pump. The first foreline pressure control system is operable to control pressure in the foreline independently of operation of the first pump.

Description

background Technical Field

[0001] Embodiments of the present disclosure relate generally to pressure control in semiconductor equipment and methods for pressure control in semiconductor equipment, and more particularly, to pressure control in a foreline of a semiconductor processing chamber. Background Art

[0002] In semiconductor manufacturing, integrated circuits (ICs) are formed on semiconductor substrates through various manufacturing steps, including etching, deposition, ion implantation, and annealing. Most of these manufacturing steps are performed in a processing chamber that is maintained under vacuum during processing. Undesirable pressure variations within the processing chamber can lead to process non-uniformities across the surface of a substrate being processed in the processing chamber, or between substrates processed over a period of time in the processing chamber. Process non-uniformities can manifest as variations in deposition or etch rates, etch depth, and etch verticality, among others.

[0003] Semiconductor manufacturers typically have multiple production lines, each of which includes multiple processing chambers of the same type designed to perform the same type of process, such as etching. Chamber-to-chamber pressure variations between chambers of the same or different production lines make it difficult to maintain processing throughput and can introduce undesirable variations between finished devices.

[0004] Therefore, there is a need for improved pressure control in semiconductor devices and manufacturing techniques. Summary of the invention

[0005] Disclosed herein is a system and method for controlling pressure in a foreline of a processing system, the system and method reducing variations in the foreline pressure. In one example, a processing system is provided, the processing system comprising a first process chamber, a first pump, a foreline, and a first foreline pressure control system. The first pump has an inlet and an outlet. The inlet of the first pump is coupled to a discharge port of the first process chamber. The foreline is coupled to the outlet of the first pump. The first foreline pressure control system is fluidically coupled to the foreline downstream of the first pump. The first foreline pressure control system is operable to control the pressure in the foreline independently of the operation of the first pump.

[0006] In another example, a processing system includes a first processing chamber, a first pump, a second processing chamber, a second pump, a second foreline segment, a foreline, a first pressure control system, a second pressure control system, and an abatement system fluidly disposed on the foreline. The first pump has an inlet coupled to an exhaust port of the first processing chamber, and an outlet coupled to an inlet of the first foreline segment. The second pump has an inlet coupled to an exhaust port of the second processing chamber, and an outlet coupled to an inlet of the second foreline segment. The foreline is coupled to outlets of the first and second foreline segments. The first pressure control system interfaces with the first foreline segment. The second pressure control system interfaces with the second foreline segment. The first pressure control system is operable to control the pressure in the first foreline segment independently of the operation of each of the first pump and the second pump. The second pressure control system is operable to control the pressure in the second foreline segment independently of the control of the pressure within the first foreline.

[0007] In yet another example, a method of controlling pressure in a processing system is provided, the method comprising measuring, at a first time, a first foreline pressure downstream of a first pump coupled to an exhaust port of a first processing chamber; comparing the measured first foreline pressure to a first set point; and adjusting the first foreline pressure based on a comparison between the measured first foreline pressure and the first set point via a first pressure control system interfaced with the foreline downstream of the first pump. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] In order to be able to understand the above-mentioned features of the present disclosure in detail, the present disclosure briefly summarized above can be described in more detail with reference to the embodiments, some of which are illustrated in the accompanying drawings. However, it should be noted that the accompanying drawings illustrate only exemplary embodiments and therefore should not be considered as limiting the scope of the present disclosure, which may allow other equally effective embodiments.

[0009] Figure 1 According to certain aspects of the present disclosure, a schematic diagram of a processing system having a processing chamber coupled to a foreline equipped with a foreline pressure control system is shown.

[0010] Figure 2 According to certain aspects of the present disclosure, a schematic diagram of a foreline pressure control system utilizing a modulating valve having a controller coupled to a process chamber pressure control system is shown.

[0011] Figure 3According to certain aspects of the present disclosure, a schematic diagram of a foreline pressure control system utilizing a mass flow controller coupled to a process chamber pressure control system is shown.

[0012] Figure 4 According to certain aspects of the present disclosure, a schematic diagram of a foreline pressure control system utilizing a modulating valve having a controller and a mass flow controller coupled to a process chamber pressure control system is shown.

[0013] Figure 5 According to certain aspects of the present disclosure, a schematic diagram of a plurality of processing systems is shown having each processing chamber coupled to a foreline equipped with a foreline pressure control system, each foreline coupled to other forelines via a common foreline.

[0014] Figure 6 According to certain aspects of the present disclosure, is a flow chart of a method for controlling pressure in a foreline.

[0015] To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures. It is understood that elements and features of one embodiment may be beneficially incorporated in other embodiments without further recitation.

[0016] Many of the details, dimensions, angles, and other features shown in the figures are merely illustrations of specific embodiments. Accordingly, other implementations may have other details, components, dimensions, angles, and features without departing from the spirit or scope of the present disclosure. In addition, other embodiments of the present disclosure may be practiced without some of the details described below. DETAILED DESCRIPTION

[0017] The present disclosure discloses systems and methods for controlling pressure in a foreline of a processing system. It has been found that changes in the foreline pressure of a processing system pose challenges to the control of pressure within a processing chamber, which can cause uniformity within semiconductor wafer processing. To address these issues, a foreline pressure control system is disclosed herein that enables the foreline pressure to be controlled in a manner that beneficially reduces pressure fluctuations within the processing chamber. The foreline pressure control system can communicate with a processing system controller to accommodate changes in set points during different stages of substrate processing within the processing system, thereby enabling improved processing uniformity in various stages of substrate processing where the internal processing chamber pressure may change. The foreline pressure system leverages a modulating valve and / or gas injection together with a pressure feedback control sequence to maintain the pressure in the foreline at a desired target set point. This advantageously results in more uniform substrate processing, increased yield, reduced waste, increased processing efficiency, and reduced cost of ownership.

[0018] Figure 1 A schematic diagram of a processing system 150 is depicted, the processing system 150 including a processing chamber 100 connected to a foreline pressure control system 140. The foreline pressure control system 140 is configured to control the pressure in a foreline 130 coupled to the processing chamber 100, thereby reducing pressure variations within the processing chamber itself. The processing chamber 100 is a vacuum processing chamber, such as an etch reactor processing chamber, an ion implantation chamber, a deposition chamber, a plasma treatment chamber, an atomic layer deposition chamber, etc. The processing chamber 100 can be, for example, a processing chamber for performing a deposition process, an etching process, an annealing process, or a cleaning process on a substrate 120. Representative chambers for performing a deposition process include deposition chambers, such as a plasma enhanced chemical vapor deposition (PECVD) chamber, a chemical vapor deposition (CVD) chamber, or a physical vapor deposition (PVD) chamber. Representative chambers for performing an etching process include a reactive ion etching chamber and an inductively coupled plasma etching chamber, etc.

[0019] The processing chamber 100 has a chamber body 102 having an interior volume 104 and a substrate support 118. A gas source 106 is coupled to the chamber body 120 through a gas inlet 108 to provide, for example, a reactive gas for processing. A plasma 116 may be formed within the interior volume 104 of the processing chamber 100 by applying RF power to a plasma generator 110. The RF power is provided from the RF power source 114 to the plasma generator 110 through a matching circuit 112.

[0020] Residual gas, such as unreacted or reacted gas from the interior volume 104 of the processing chamber 100, is exhausted from the interior volume 104 through the chamber exhaust port 122. A throttle valve 124 is disposed near the chamber exhaust port 122 to control the pressure within the interior volume 104 of the processing chamber 100. An outlet of the throttle valve 124 is coupled to an inlet of a chamber exhaust pump 126. An outlet of the chamber exhaust pump 126 is coupled to a foreline 130.

[0021] The foreline 130 serves as a conduit for routing residual gas out of the processing chamber 100 through the chamber exhaust pump 126 and the throttle valve 124. A foreline pressure control system 140 is coupled to the foreline 130 downstream of the chamber exhaust pump 126 and upstream of a foreline pump 136. The foreline pump 136 is used to maintain flow within the foreline 130 away from the processing chamber 100.

[0022] The residual gas in the foreline 130 may contain materials that are not desired to be released into the atmosphere or that may damage downstream equipment (e.g., the foreline pump 136). For example, the residual gas may contain compounds and / or etchants from the etching process. Residual gas that is not suitable for atmospheric release can be adjusted to a safe state by an optional pre-pump abatement system 134. The optional pre-pump abatement system 134 can be located upstream of the foreline pump 136 on the foreline 130. The pre-pump abatement system includes, but is not limited to, units that can assist in process gas disposal, which can be plasma or absorption type. Other abatement systems can be used to dispose of residual gas downstream of the foreline pump 136. Figure 1 Optional emission treatment equipment is shown. Traditional examples of abatement systems include traps and or scrubbers.

[0023] In general, the processing chamber 100 is communicatively coupled to a system controller 128. The system controller 128 is configured to control the operation of the processing chamber 100. The system controller 128 or other appropriately proposed controllers may be configured to control the pressure for the foreline 130. In one example, the controller configured to control the pressure for the foreline 130 is configured to determine or measure the pressure within the foreline 130, compare the determined or measured pressure with a set point, and provide instructions to a control system interfaced with the foreline 130 based on the comparison between the determined or measured foreline pressure and the set point. The set point may be retrieved from a memory accessible by the controller. The memory may include a process recipe for controlling a process within the process chamber. The process recipe may include different foreline pressure step points associated with various stages of the process recipe, wherein each stage of the process recipe causes the processing chamber to experience different operating and / or processing conditions, such as different processing chamber pressures, different processing chamber gas compositions, and the like. When the system controller 128 controls the operation of the processing chamber and a different controller controls the pressure of the foreline 130, the set points associated with different stages of the process are communicated from the system controller 128 to a second controller that is different from the first controller. The set point for one stage in the process can be different from the set point for a second stage. For example, but not limited to, the set point for a first stage such as processing a substrate in the presence of a first gas can be different from the set point for a second stage of the process such as processing a substrate in the presence of a second gas. In another non-limiting example, the set point for a first stage such as plasma processing a substrate can be different from the set point for a second stage of the process such as cleaning the chamber after removing the substrate.

[0024] In one example, the process chamber 100 is communicatively coupled to a single controller (e.g., system controller 128) that is configured to instruct pressure control to a pressure control device that is capable of regulating the pressure in the foreline 130. In some embodiments, the process chamber controller (e.g., system controller 128) Figure 1 The system controller 128 shown in FIG. 1 may be configured to provide instructions to a foreline pressure control system 140 , which may or may not include a second controller separate and distinct from the system controller 128 .

[0025] In such Figure 1In one embodiment shown, the processing chamber 100 is communicatively coupled to a system controller 128. The system controller 128 may contain hardware and software that enables an operator to, for example, instruct, set, start, or stop desired functions of the system. The system controller 128 controls the operation of the processing chamber 100, such as the operation of the throttle valve 124, the first pump 126, the RF power source 114, the gas source 106, and the like, so that the substrate 120 can be processed within the processing chamber 100.

[0026] During processing of the substrate 120, the system controller 100 controls various internal conditions of the processing chamber 100, such as pressure, temperature, and the like. For example, when etching the substrate 120 within the processing chamber 100, the system controller 128 controls the pressure within the internal volume 104 during different stages of the etching process. Each stage of the etching process can have a different target internal volume pressure, which can be maintained via operation of the gas source 106, the throttle valve 124, and / or the first pump 136 as directed by the system controller 128. For example, one stage of the etching process can have a first target internal volume pressure that is different from a second target internal volume pressure at another stage of the etching process. Each target internal volume pressure has an associated foreline target pressure set point.

[0027] The system controller 128 is configured to provide a foreline target pressure set point to a foreline pressure system controller 144 of the foreline pressure control system 140. The system controller 128 transmits a signal indicating the foreline target pressure set point to the foreline pressure control system 140. The foreline pressure control system 140 operates to maintain the foreline pressure at or near the foreline target pressure set point. The foreline pressure system controller 144 of the foreline pressure control system 140 includes a pressure sensor 142 and a pressure regulating device 146. The pressure sensor 142 provides foreline pressure information to the foreline pressure system controller 144. The foreline pressure system controller 144 controls the operation of the pressure regulating device 146 to adjust the pressure in the foreline 130 based on the foreline target pressure set point. The foreline pressure information provided to the foreline pressure system controller 144 by the sensor 142 can also be utilized to control the operation of the pressure regulating device 146 to adjust the pressure in the foreline 130 based on the sensed foreline pressure.

[0028] Figure 2 An exemplary schematic diagram is depicted of the foreline pressure control system 140. As described above, the foreline pressure control system 140 includes a pressure sensor 142, a foreline pressure system controller 144, and a pressure regulating device 146. Figure 2The pressure regulating device 146 shown in FIG. 1 includes an actuator 248 coupled to a modulating valve 246 .

[0029] In general, the pressure sensor 142 may be a pressure sensor suitable for measuring the pressure within the foreline 130. In other words, the pressure sensor 142 may be a pressure sensor suitable for determining the pressure within the foreline 130. The pressure may be mechanically sensed and then converted into a digital or serial soft link signal for feedback of the signal by connecting the pressure sensor 142 to an output line 252 of the foreline pressure system controller 144. The output line 252 is communicatively coupled to the foreline pressure system controller 144 to provide an input pressure signal to the foreline pressure system controller 144. The input pressure signal is used as a state regulator of the pressure sensor 142 to adjust the foreline 130 pressure by modulation of the modulation valve 246.

[0030] The foreline pressure system controller 144 is configured to receive the pressure from the system controller 128 ( Figure 1 250 ) receives the communication, and receives the communication from the pressure sensor 142 through the output line 252. The foreline pressure system controller 144 processes the communication and outputs a voltage signal to the actuator 248. The actuator 248 is mechanically coupled to the modulating valve 246. For example, the foreline pressure system controller 144 can receive a signal indicating the desired foreline 130 pressure (i.e., the set point) from the system controller 128. The pressure sensor 142 will provide the current pressure state to the foreline pressure system controller 144 through the output line 252. The sensed pressure signal is compared with the set point by the foreline pressure system controller 144. Based on this comparison, the foreline pressure system controller 144 will instruct the actuator 248 to operate the throttling modulating valve 246 to increase, decrease or maintain the pressure in the foreline 130 through the output line 254. The rapid response of the pressure feedback and the throttling modulating valve 246 provided to the foreline pressure system controller 144 by the pressure sensor 142 enables the desired set point pressure to be maintained in the foreline 130.

[0031] The actuator 248 may be a motor, a pneumatic or hydraulic actuator, or other suitable actuator for controlling the operation of the regulating valve 246. The modulating valve 246 may be one of various types of typical valves, such as a butterfly valve, a ball valve, a V-ball valve, a gate valve, a stop valve, or an angle valve, suitable for controlling the pressure of a gas line. The modulating valve 246 may be fast acting, with a throttling speed of less than one second.

[0032] Figure 3 An exemplary schematic diagram of another foreline pressure control system 300 is depicted. The foreline pressure control system 300 may be used instead of Figure 1Similar to the foreline pressure control system 140 , the foreline pressure control system 300 includes a pressure sensor 142 , a foreline pressure system controller 144 and a pressure regulating device 146 . Figure 3 The pressure regulating device 146 of the foreline pressure control system 300 depicted in FIG. 1 includes a mass flow controller 346, a gas source 306, and an injection port 358. The injection port 358 is disposed on the foreline 130. The operation of the mass flow controller 346 is controlled by the foreline pressure system controller 144 to regulate the amount of gas provided by the gas source 306 into the foreline 130 through the injection port 358.

[0033] Similar to Figure 2 The operation of the modulating valve 246 is performed by the foreline pressure system controller 144 via the input line 256 from the Figure 1 The system controller 128 receives the communication and receives the communication from the pressure sensor 142 through the output line 252. The foreline pressure system controller 144 will process the communication and deliver a voltage signal to the mass flow controller 346 through the output signal line 354 to control the amount of gas from the gas source 306 to flow to the injection port 358 and into the foreline 130. The gas source 306 is coupled to the inlet of the mass flow controller 346 through the gas supply line 308. The gas line 310 couples the gas output of the mass flow controller 346 to the injection port 358 so that gas can be controllably delivered from the gas source 306 to the foreline 130 at a dynamic rate so that the pressure in the foreline 342 can be maintained or adjusted to a desired target set point based on the pressure sensed by the pressure sensor 342.

[0034] In one embodiment, the gas source 306 may be one or more cylinder gas bottles. In another embodiment, the gas source 306 may be utility gas provided with the building. The gas source 306 may be configured to provide an inert gas, such as helium, neon, and argon. However, other non-reactive gases, such as air, may also be utilized.

[0035] Figure 4 An exemplary schematic diagram of a foreline pressure control system 400 is depicted. The foreline pressure control system 400 may be used in place of Figure 1 Similar to the foreline pressure control system 140 , the foreline pressure control system 400 includes a pressure sensor 142 , a foreline pressure system controller 144 and a pressure regulating device 146 . Figure 4The pressure regulating device 146 of the foreline pressure control system 400 shown in FIG. 1 includes both an actuator 248 coupled to a modulating valve 246, and a gas source 306 coupled to an injection port 358 through a mass flow controller 346. The injection port 358 is disposed on the foreline 130. The operation of the mass flow controller 346 and the modulating valve 246 is controlled by the foreline pressure system controller 144 to adjust the amount of gas provided into the foreline 130 through the injection port 358 by the gas source 306, and / or to control the conductance within the foreline 130 using the modulating valve 246.

[0036] The foreline pressure system controller 144 can receive the pressure from the system controller 128 (such as Figure 1 254) and receives communications from the pressure sensor 142 via the output line 252. The foreline pressure system controller 144 will process the communications and control the operation of one or both of the mass flow controller 346 and the modulating valve 246 to control the pressure in the foreline 130. In one example, a voltage signal is provided to one or both of the actuators 248 that throttle the modulating valve 246 to open or close or between the two via the output line 254, and / or allow a determined amount of gas from the gas source 306 to flow to the injection port 358 via the mass flow controller 346. The gas source 306 is coupled to the inlet of the mass flow controller 346 via the gas supply line 308. Gas line 310 couples the output of mass flow controller 346 to injection port 358 so that gas can be delivered from gas source 306 to foreline 130 at a dynamic rate so that the pressure in foreline 342 can be maintained at or adjusted to a desired pressure based on a target set point provided by system controller 128 and a state indication of pressure sensed by pressure sensor 342. Feedback adjustments are continuously received by foreline pressure system controller 144 to achieve pressure control of foreline 130 and ultimately to achieve pressure control from Figure 1 The pressure of the processing chamber 100 is controlled.

[0037] In one embodiment, a feed-forward pressure control scheme is considered to predict changes in pressure. An empirical analysis of the equipment operation under steady-state operation is performed to determine system fluctuations. For example, an initial pressure pulse to start a piece of downstream equipment while the processing chamber is processing a substrate may cause a pressure change inside the processing chamber, such as a 5 mTorr pressure change, until the pressure is adjusted using an embodiment of the foreline pressure control system 300. This adjustment can be recorded in the control logic and used to predict the pressure change when the equipment is next started up, thereby reducing or substantially eliminating system pressure changes.

[0038] In one embodiment of the foreline pressure control system 300, the feedback signal may be delayed through the use of, for example, a timer algorithm or a valve position indicator. Figure 4 Embodiments provide for controlling the foreline pressure using both the injection of gas into the foreline 130 and the throttling of the flow within the foreline 130. For example, the system controller 128 provides a first target set point corresponding to a first time or stage of a process performed in the processing chamber 100 to the foreline pressure system controller 144. The initial response to controlling the pressure may be providing a voltage signal to the actuator 248, which throttles the modulating valve 246. If the target set point pressure is not reached, the foreline pressure system controller 144 may then initiate a voltage signal to the mass flow controller 346 to allow a determined amount of gas to be injected into the foreline 130. In another embodiment, the mass flow controller is first used to change the foreline pressure, and then the valve is modulated if necessary. In yet another embodiment, a modulating valve stem position indicator is used.

[0039] In yet another embodiment, the system controller 128 provides a second target set point to the foreline pressure system controller 144, the second target set point corresponding to a second time or stage of a process performed in the processing chamber 100 that is different from the previous time / stage. The foreline pressure system controller 144 provides instructions to one or both of the modulating valve 246 and the mass flow controller 346 to cause the foreline pressure to begin to coincide with the second set point.

[0040] Figure 5 An exemplary schematic diagram depicting a network 550 of processing chambers 500 is shown. Figure 5 , three process chambers 500a, 500b, 500c are shown in the example depicted in FIG, but the network 550 includes one or more process chambers 500 coupled to a common foreline 560. In one embodiment, each process chamber 500a, 500b, and 500c of the network 550 of process chambers 500 is coupled to the common foreline 130 via a respective one of the foreline segments 530a, 530b, 530c. Figure 5 Independent foreline pressure control systems 540a, 540b, and 540c are shown, but each foreline 530a, 530b, 530c can be coupled together upstream of a single foreline pressure control system. Figure 5A common optional pre-pump abatement system 534, foreline pump 536, and optional exhaust disposal device 532 are shown, but for each of the process chambers 500a, 500b, 500c, there may be a separate optional pre-pump abatement system 534, foreline pump 536, and optional exhaust disposal device 532 within the network 550 of process chambers 500. In another embodiment, the process chambers 500a, 500b, and 500c are coupled to a single foreline pressure control system and multiple downstream devices in parallel, for example, one path may be the optional pre-pump abatement system 534, foreline pump 536, and another path may be the foreline pump 536 and optional exhaust disposal device 532.

[0041] During normal processing operations, the pressure of the processing chambers 500a, 500b, 500c can vary. Each processing chamber 500a, 500b, 500c is regulated by their independent system controllers 528a, 528b, 528c, which communicate with their corresponding foreline pressure control systems 544a, 544b, 544c to regulate the pressure in the foreline 530a, 530b and 530c. In one example, the system controllers 528a, 528b, 528c are operable to maintain the pressure variation within each processing chamber 500a, 500b, 500c to less than 50mTorr. Therefore, the implementation of the foreline pressure control system 544a, 544b, 544c can be as follows Figure 2 , Figure 3 or Figure 4 Any combination shown can be used to control the pressure within the structure of the foreline 530a, 530b and 530c.

[0042] Figure 6 6 is a flow chart of a method 600 for controlling pressure in a foreline, such as the foreline 130 of the processing system 150, 660 or other suitable processing chamber. The method 600 begins at operation 610 by measuring a first foreline pressure downstream of a first pump coupled to an exhaust port of a first processing chamber at a first time. As described above, the first foreline pressure may be measured by the pressure sensor 142 and provided to the foreline pressure system controller 144. The first time may be associated with a first stage of a process performed in the processing chamber 100.

[0043] At operation 620, the measured first foreline pressure is compared with a first foreline pressure set point by a foreline pressure control system. The first foreline pressure set point may be provided to the foreline pressure control system in any suitable manner. In one example, the foreline pressure control system obtains the first foreline pressure set point from a system controller that controls the operation of the processing system. The first foreline pressure set point may be associated with a particular stage or time of a substrate process performed in the processing system. In some embodiments, a plurality of foreline pressure set points are provided to the foreline pressure control system from the system controller in batches or over time, wherein each foreline pressure set point is associated with a different time or stage of a substrate process performed in the processing system. The pressure within the processing chamber may be different at different times or stages of performing a substrate process in the processing system.

[0044] At operation 630, the first foreline pressure is adjusted by operation of a first pressure control system interfaced with the foreline downstream of the first pump based on a comparison between the measured first foreline pressure and a first set point. The first foreline pressure may be adjusted by varying the flow conductance of the foreline by operation of a throttle valve disposed downstream of a pump coupled to the chamber exhaust. Additionally or alternatively, the first foreline pressure may be adjusted by introducing a gas into the foreline disposed downstream of a pump coupled to the chamber exhaust.

[0045] The method 600 may also include measuring a second foreline pressure downstream of a second pump coupled to an exhaust port of the second process chamber, comparing the measured second foreline pressure to a second set point, and adjusting the second foreline pressure by a second pressure control system interfaced with the foreline downstream of the second pump based on the comparison between the measured second foreline pressure and the second set point.

[0046] Thus, methods and systems for controlling pressure in a foreline independent of the operation of a pump or throttle valve coupled immediately downstream of a chamber exhaust have been disclosed. The foreline pressure control system reduces pressure fluctuations both within the foreline and within the processing chamber. The foreline pressure control system accommodates changes in set points during different stages of substrate processing, enabling improved processing uniformity, increased throughput, reduced waste, improved processing efficiency, and lower cost of ownership.

[0047] While the foregoing is directed to embodiments of the present disclosure, other and further embodiments of the disclosure may be derived without departing from the basic scope thereof, the scope of which is determined by the appended claims.

Claims

1. A processing system comprising: A controller, the controller being configured to: determining, at a first time, a first foreline pressure in a foreline downstream of a first pump coupled to an exhaust port of a first processing chamber; comparing the determined first foreline pressure to a first set point; and Based on the comparison between the determined first foreline pressure and the first set point, instructions are provided to a first pressure control system interfaced with the foreline downstream of the first pump to adjust the first foreline pressure.

2. The processing system of claim 1, wherein the first pressure control system comprises: A foreline pressure system controller is configured to receive the first set point from a system controller configured to control operation of the first process chamber.

3. The processing system of claim 2, further comprising: the first pressure control system; a pressure sensor coupled to the foreline pressure system controller; and A foreline pressure regulating device is coupled to the foreline pressure system controller and is configured to control the pressure in the foreline based on the pressure indicator obtained by the pressure sensor.

4. The processing system of claim 3, wherein the foreline pressure regulating device comprises a modulating valve disposed in the foreline.

5. The treatment system of claim 4, wherein the modulating valve has a throttling speed of less than 1 second.

6. The processing system of claim 3, wherein the foreline pressure regulating device comprises a gas injection system configured to introduce gas into the foreline downstream of the first pump.

7. The processing system of claim 6, wherein the gas injection system further comprises a mass flow controller.

8. The processing system of claim 6, wherein the gas injection system further comprises a gas source.

9. The processing system of claim 8, wherein the gas source is configured to supply nitrogen, air, helium, neon, or argon.

10. The processing system of claim 8, wherein the gas source comprises at least one of: a facility gas supply, ambient air, or a gas cylinder.

11. The processing system of claim 2, wherein the system controller is configured to output the first set point and the second set point to the foreline pressure system controller, the first set point and the second set point being based on target foreline pressures from different stages of a process performed in the processing chamber.

12. The processing system of claim 3, wherein the foreline pressure regulating device is operable to maintain the foreline pressure within 50 mTorr of the set point.

13. The processing system of claim 1, further comprising: the first process chamber, the first process chamber having the controller coupled to the first process chamber; a first pump having an inlet and an outlet, the inlet of the first pump being coupled to the exhaust port of the first process chamber, the outlet of the first pump being coupled to the foreline; and The first foreline pressure control system is fluidly coupled to the foreline downstream of the first pump, the first foreline pressure control system being operable to control pressure in the foreline independent of operation of the first pump.

14. The processing system of claim 13, further comprising: An abatement system is fluidly coupled to the foreline downstream of the first foreline pressure control system.

15. The processing system of claim 13, wherein the foreline comprises a first feed zone coupled to a main zone and a second feed zone coupled to the first processing chamber and the second feed zone coupled to the second processing chamber.

16. The processing system of claim 15, further comprising: A second foreline pressure control system is coupled to the second feed zone, the second foreline pressure control system being operable to control pressure in the second feed zone independently of the first foreline pressure control system.

17. The processing system of claim 1, further comprising: The first pressure control system, wherein the first pressure control system includes a pressure sensor, a modulating valve, a front-stage pipeline pressure system controller and a second pressure control system, and the second pressure control system includes a mass flow controller, a gas source and a gas injection port.

18. A processing system comprising: a first processing chamber having an exhaust port; a first pump having an inlet coupled to the exhaust port of the first process chamber and an outlet coupled to an inlet of a first foreline segment; a second processing chamber having an exhaust port; a second pump having an inlet coupled to the exhaust port of the second process chamber and an outlet coupled to an inlet of a second foreline segment; A front-stage pipeline, the front-stage pipeline is coupled to the outlets of the first front-stage pipeline section and the second front-stage pipeline section; a first pressure control system, the first pressure control system being connected to the first front-stage pipeline section; and A second pressure control system, the second pressure control system is connected to the second foreline segment, wherein the first pressure control system is operable to control the pressure in the first foreline segment independently of the operation of each of the first pump and the second pump, and the second pressure control system is operable to control the pressure in the second foreline segment independently of the control of the pressure in the first foreline.

19. The processing system of claim 18, further comprising: An abatement system is fluidly coupled to the foreline.

20. A method of controlling pressure in a processing system, the method comprising the steps of: measuring, at a first time, a first foreline pressure downstream of a first pump coupled to an exhaust port of a first process chamber; comparing the measured first foreline pressure to a first set point; and The first foreline pressure is adjusted based on the comparison between the measured first foreline pressure and the first set point by a first pressure control system interfaced with the foreline downstream of the first pump.

21. The method of claim 20, wherein the step of adjusting the first foreline pressure further comprises the following steps: A control valve is throttled or gas is injected into the foreline based on the comparison.

22. The method of claim 20, further comprising the steps of: measuring a second foreline pressure downstream of a second pump coupled to an exhaust port of the second process chamber; comparing the measured second foreline pressure to a second set point; The second foreline pressure is adjusted based on the comparison between the measured second foreline pressure and the second set point by a second pressure control system interfaced with the foreline downstream of the second pump.

23. The method of claim 20, further comprising the steps of: measuring a second foreline pressure downstream of the first pump at a second time; comparing the measured second foreline pressure to a second set point; and The second foreline pressure is adjusted, by the first pressure control system, based on the comparison between the measured second foreline pressure and a second set point, wherein the first set point is based on a first stage of a process performed in the first processing chamber and the second set point is based on a second stage of the process performed in a second processing chamber.

Images