Systems and methods for controlling foreline pressure

Abstract

Disclosed herein are systems and methods for controlling pressure in a foreline of a processing system that reduce foreline pressure fluctuations. In one embodiment, a processing system is provided that includes a first processing 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 the outlet of the first processing chamber. The foreline is coupled to the outlet of the first pump. The first foreline pressure control system is fluidly connected 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

[Technical Field]

[0001] FIELD OF THE DISCLOSURE

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

[0002] 2. Description of Related 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 processing chambers that are maintained under vacuum during processing. Unwanted pressure fluctuations within the processing chamber can result in process non-uniformities over time across the surface of a substrate being processed in the processing chamber, or between substrates being processed in the processing chamber. Process non-uniformities can manifest as variations in deposition or etch rate, etch depth, and etch verticality, among other things.

[0003]

[0003] Semiconductor manufacturers typically have multiple manufacturing lines, each line equipped with 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 on the same or different manufacturing lines can make processing yields difficult to maintain and can introduce undesirable variations between finished devices.

[0004]

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

[0005] Systems and methods for controlling pressure in a foreline of a processing system that reduce foreline pressure fluctuations are disclosed herein. In one embodiment, a processing system is provided that includes a first processing 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 the outlet of the first processing chamber. The foreline is coupled to the outlet of the first pump. The first foreline pressure control system is fluidly connected 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.

[0006] In another embodiment, 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 a removal system fluidly disposed in the foreline. The first pump has an inlet coupled to an exhaust port of the first processing chamber and an exhaust port 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 exhaust port coupled to an inlet of the second foreline segment. The foreline is coupled to the exhaust ports of the first and second foreline segments. The first pressure control system is operative to control pressure in the first foreline segment independently of operation of each of the first and second pumps. The second pressure control system is operable to control the pressure in the second foreline segment independently from controlling the pressure in the first foreline.

[0007]

[0007] In yet another embodiment, a method for controlling pressure in a processing system is provided that includes measuring a first foreline pressure downstream of a first pump connected to an exhaust port of a first processing chamber at a first time, comparing the measured first foreline pressure to a first set point, and adjusting the first foreline pressure by a first pressure control system coupled to the foreline downstream of the first pump based on the comparison between the measured first foreline pressure and the first set point.

[0008]

[0008] So that the above-mentioned features of the present disclosure may be understood in detail, a more particular description of the present disclosure, briefly summarized above, will be had by reference to embodiments. Some embodiments are illustrated in the accompanying drawings. It should be noted, however, that the accompanying drawings illustrate only exemplary embodiments and therefore should not be considered to limit the scope of the present disclosure, as other equally effective embodiments may also be permitted. [Brief explanation of the drawings]

[0009] [Figure 1]

[0009] FIG. 1 is a schematic diagram of a processing system having a processing chamber coupled to a foreline with a foreline pressure control system according to certain aspects of the present disclosure. [Figure 2]

[0010] FIG. 1 is a schematic diagram of a foreline pressure control system utilizing a regulator valve having a controller coupled to a process chamber pressure control system in accordance with certain aspects of the present disclosure. [Figure 3]

[0011] FIG. 1 is a schematic diagram of a foreline pressure control system utilizing a mass flow controller coupled to a process chamber pressure control system, in accordance with certain aspects of the present disclosure. [Figure 4]

[0012] FIG. 1 is a schematic diagram of a foreline pressure control system utilizing a regulator valve having a controller and a mass flow controller coupled to a process chamber pressure control system in accordance with certain aspects of the present disclosure. [Figure 5]

[0013] 1 is a schematic diagram of a multiple processing system having each processing chamber connected to a foreline with a foreline pressure control system, each foreline being connected to other forelines through a common foreline, in accordance with certain aspects of the present disclosure; [Figure 6]

[0014] FIG. 1 is a flow diagram of a method for controlling pressure in a foreline in accordance with certain aspects of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0010]

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

[0011]

[0016] Many of the details, dimensions, angles, and other features shown in the drawings are merely illustrative of particular implementations. Thus, other implementations may have other details, components, dimensions, angles, and features without departing from the spirit or scope of the present disclosure. Additionally, further implementations of the present disclosure may be practiced without some of the details described below.

[0012]

[0017] The present disclosure provides a system and method for controlling the pressure in the foreline of a processing system. It has been found that fluctuations in the foreline pressure of a processing system can present challenges for controlling the pressure within a processing chamber and affect uniformity within the processing of semiconductor wafers. 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 a processing chamber. The foreline pressure control system can communicate with a processing system controller to accommodate setpoint changes at various stages of substrate processing within the processing system, thereby improving process uniformity through various stages of substrate processing where internal processing chamber pressure may vary. The foreline pressure system utilizes a regulator valve and / or gas injection in conjunction with a pressure feedback control sequence to maintain the pressure within the foreline at a desired target setpoint. This advantageously results in more uniform processing of substrates, increased yield, reduced waste, improved processing efficiency, and reduced cost of ownership.

[0013]

[0018] FIG. 1 shows a schematic diagram of a 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 within a foreline 130 coupled to the processing chamber 100, which in turn reduces pressure fluctuations within the processing chamber itself. The processing chamber 100 may be a vacuum processing chamber such as an etch reactor processing chamber, an ion implantation chamber, a deposition chamber, a plasma processing chamber, an atomic layer deposition chamber, or the like. The processing chamber 100 may be, for example, a processing chamber for performing deposition processes, etching processes, annealing processes, or cleaning processes, among others, on a substrate 120. Exemplary chambers for performing deposition processes include deposition chambers such as plasma-enhanced chemical vapor deposition (PECVD) chambers, chemical vapor deposition (CVD) chambers, or physical vapor deposition (PVD) chambers. Exemplary chambers for performing etching processes include reactive ion etch chambers and inductively coupled plasma etch chambers, among others.

[0014]

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

[0015]

[0020] Residual gases, such as unreacted or reacted gases from the interior volume 104 of the processing chamber 100, are exhausted from the interior volume 104 through a chamber exhaust port 122. A throttle valve 124 is disposed proximate to the chamber exhaust port 122 to control the pressure within the interior volume 104 of the processing chamber 100. The exhaust port of the throttle valve 124 is connected to the inlet of a chamber exhaust pump 126. The exhaust port of the chamber exhaust pump 126 is connected to a foreline 130.

[0016]

[0021] The foreline 130 serves as a conduit for directing residual gases exiting 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 the foreline pump 136. The foreline pump 136 is utilized to maintain flow in the foreline 130 away from the processing chamber 100.

[0017]

[0022] Residual gases in the foreline 130 may contain materials that are undesirable for release to the atmosphere or that could damage downstream equipment, such as the foreline pump 136. For example, the residual gases may include compounds and / or etchants from an etching process. Residual gases unsuitable for release to the atmosphere can be conditioned to a safe state via an optional pre-pump removal system 134. The optional pre-pump removal system 134 may be located upstream of the foreline pump 136 on the foreline 130. Pre-pump removal systems include, but are not limited to, units that can serve for process gas treatment, which may be plasma or absorption-type. Other removal systems may also be used to treat residual gases downstream of the foreline pump 136. FIG. 1 illustrates an optional exhaust treatment system. Examples of conventional removal systems include traps and / or scrubbers.

[0018]

[0023] Generally, 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 suitably proposed controller, may be configured to control the pressure in the foreline 130. In one embodiment, the controller configured to control the pressure in the foreline 130 is configured to determine or measure the pressure in the foreline 130, compare the determined or measured pressure to a setpoint, and command a control system associated with the foreline 130 based on the comparison between the determined or measured foreline pressure and the setpoint. The setpoint may be read from a memory accessible to the controller. The memory may include a process recipe for controlling processing in the processing chamber. The process recipe may include different foreline pressure step points associated with various stages of the process recipe, each stage of the process recipe subjecting the processing chamber to different operating and / or processing conditions, such as different process chamber pressures, different process chamber gas compositions, etc. When the system controller 128 controls the operation of the processing chamber and a separate controller controls the pressure in the foreline 130, setpoints associated with different process stages are communicated from the system controller 128 to a second controller different from the first controller. The setpoint for one stage of a process may be different from the setpoint for a second stage. For example, but not by way of limitation, the setpoint for a first stage, such as processing a substrate in the presence of a first gas, may be different from the setpoint for a second stage of a process, such as processing a substrate in the presence of a second gas. In another non-limiting example, the setpoint for a first stage, such as plasma processing a substrate, may be different from the setpoint for a second stage of a process, such as cleaning the chamber after removing the substrate.

[0019]

[0024] In one example, processing chamber 100 is communicatively coupled to a single controller (e.g., system controller 128) configured to direct pressure control to pressure control devices capable of adjusting pressure in foreline 130. In some embodiments, the processing chamber controller (system controller 128 depicted in FIG. 1 ) can be configured to direct a foreline pressure control system 140, which may or may not include a second controller that is separate and distinct from system controller 128.

[0020]

[0025] 1 , the processing chamber 100 is communicatively coupled to a system controller 128. The system controller 128 may include, for example, hardware and software that allows an operator to command, configure, start, or stop desired functions of the system. The system controller 128 controls the operation of the processing chamber 100 (e.g., operation of the throttle valve 124, the first pump 126, the RF power source 114, the gas source 106, etc.) to enable the substrate 120 to be processed in the processing chamber 100.

[0021]

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

[0022]

[0027] System controller 128 is configured to provide a foreline target pressure setpoint to a foreline pressure system controller 144 of foreline pressure control system 140. System controller 128 sends a signal indicative of the foreline target pressure setpoint to foreline pressure control system 140. Foreline pressure control system 140 operates to maintain the foreline pressure at or near the foreline target pressure setpoint. Foreline pressure system controller 144 of foreline pressure control system 140 includes a pressure sensor 142 and a pressure regulation device 146. Pressure sensor 142 provides foreline pressure information to foreline pressure system controller 144. Foreline pressure system controller 144 controls operation of pressure regulation device 146 to regulate the pressure in foreline 130 based on the foreline target pressure setpoint. The foreline pressure information provided by the sensor 142 to the foreline pressure system controller 144 may also be utilized to control the operation of a pressure regulation device 146 that adjusts the pressure within the foreline 130 based on the sensed foreline pressure.

[0023]

[0028] 2 shows an exemplary schematic diagram of foreline pressure control system 140. As described above, foreline pressure control system 140 includes pressure sensor 142, foreline pressure system controller 144, and pressure regulation device 146. Pressure regulation device 146 shown in FIG. 2 includes an actuator 248 coupled to a regulator valve 246.

[0024]

[0029] Generally, pressure sensor 142 may be any pressure sensor suitable for measuring the pressure within foreline 130. In other words, pressure sensor 142 may be any pressure sensor suitable for determining the pressure within foreline 130. The pressure may be mechanically sensed and converted to a digital or serial soft link signal that is then used for a feedback signal through output wires 252 connecting pressure sensor 142 to foreline pressure system controller 144. Output wires 252 are communicatively coupled to foreline pressure system controller 144 to provide an input pressure signal to foreline pressure system controller 144. The input pressure signal serves as a condition regulator for pressure sensor 142 to regulate foreline 130 pressure by adjusting regulator valve 246.

[0025]

[0030] Foreline pressure system controller 144 is configured to receive communications from system controller 128 (shown in FIG. 1) via input wires 256 and from pressure sensor 142 via output wires 252. Foreline pressure system controller 144 processes the communications and outputs a voltage signal to actuator 248. Actuator 248 is mechanically coupled to regulator valve 246. For example, foreline pressure system controller 144 may receive a signal from system controller 128 indicating a desired foreline 130 pressure, i.e., a set point. Pressure sensor 142 provides a current pressure status to foreline pressure system controller 144 via output wires 252. The sensed pressure signal is compared to the set point by foreline pressure system controller 144. Based on the comparison, foreline pressure system controller 144 commands actuator 248 via output line 254 to operate throttle regulator valve 246 to increase, decrease, or maintain pressure in foreline 130. The pressure feedback provided by pressure sensor 142 to foreline pressure system controller 144 and the rapid response of throttling valve 246 facilitate maintaining a desired set point pressure in foreline 130 .

[0026]

[0031] Actuator 248 may be a motor, a pneumatic or hydraulic actuator, or other suitable actuator for controlling the operation of regulator valve 246. Regulator valve 246 may be one of various types of typical valves suitable for controlling the pressure in a gas line, such as, for example, a butterfly valve, a ball valve, a V-ball valve, a gate valve, a globe valve, or an angle valve. Regulator valve 246 may be fast acting, having a throttle speed of less than one second.

[0027]

[0032] FIG. 3 shows an exemplary schematic diagram of another foreline pressure control system 300. The foreline pressure control system 300 can be used in place of the foreline pressure control system 140 shown in FIG. 1. Like 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 regulation device 146. The pressure regulation device 146 of the foreline pressure control system 300 shown in FIG. 3 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 through the injection port 358 into the foreline 130.

[0028]

[0033] Similar to the operation of regulator valve 246 of FIG. 2, foreline pressure system controller 144 receives communications from system controller 128 of FIG. 1 via input wire 256 and from pressure sensor 142 via output wire 252. Foreline pressure system controller 144 processes the communications and sends a voltage signal via output signal line 354 to mass flow controller 346, which controls the amount of gas flowing from gas source 306 to injection port 358 and foreline 130. Gas source 306 is coupled to the inlet of mass flow controller 346 via gas supply line 308. Gas line 310 couples the gas output of mass flow controller 346 to injection port 358, enabling gas to be controllably delivered from gas source 306 to foreline 130 at a dynamic rate that allows the pressure in foreline 342 to be maintained or adjusted to a desired target set point based on the pressure sensed by pressure sensor 342.

[0029]

[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 facility gas provided in 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.

[0030]

[0035] FIG. 4 shows an exemplary schematic diagram of a foreline pressure control system 400. The foreline pressure control system 400 can be used in place of the foreline pressure control system 140 shown in FIG. 1. Like 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 regulation device 146. The pressure regulation device 146 of the foreline pressure control system 400 shown in FIG. 4 includes both an actuator 248 coupled to a regulator valve 246 and a gas source 306 coupled to an injection port 358 by a mass flow controller 346. The injection port 358 is located on the foreline 130. The operation of the mass flow controller 346 and the regulator valve 246 is controlled by the foreline pressure system controller 144 to adjust the amount of gas provided by the gas source 306 to the foreline 130 through the injection port 358 and / or to control the conductance in the foreline 130 using the regulator valve 246.

[0031]

[0036] The foreline pressure system controller 144 may receive communications from the system controller 128 (shown in FIG. 1) via input wires 256 and from the pressure sensor 142 via output wires 252. The foreline pressure system controller 144 processes the communications and controls the operation of one or both of the mass flow controller 346 and the throttle valve 246 to control the pressure in the foreline 130. In one embodiment, a voltage signal is provided to the actuator 248, the throttle valve 246, or both to open, close, or something in between via output line 254 and / or to allow a determined amount of gas from the gas source 306 to flow through the mass flow controller 346 to an inlet 358. The gas source 306 is coupled to the inlet of the mass flow controller 346 via a gas supply line 308. Gas line 310 connects the output of mass flow controller 346 to inlet port 358, allowing gas to be controllably delivered from gas source 306 to foreline 130 at a dynamic rate that allows the pressure in foreline 342 to be maintained or adjusted to a desired pressure based on a target set point provided by system controller 128 and a status indication of the 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 the pressure of processing chamber 100 of FIG.

[0032]

[0037] In one embodiment, a feedforward pressure control scheme is contemplated to predict pressure fluctuations. Equipment behavior during steady-state operation is empirically analyzed to determine system fluctuations. For example, an initial pressure pulse starting a downstream equipment while the processing chamber is processing a substrate may cause a pressure fluctuation of, for example, 5 mTorr in the processing chamber until the pressure is adjusted using an embodiment of the foreline pressure control system 300. This adjustment is recorded in the control logic and used to predict pressure fluctuations the next time the equipment is started, thereby reducing or substantially eliminating system pressure fluctuations.

[0033]

[0038] In one embodiment of the foreline pressure control system 300, the feedback signal may be delayed, for example, through the use of a timer algorithm or a valve position indicator. The embodiment of FIG. 4 combines gas injection into the foreline 130 and flow throttling within the foreline 130 to control the foreline pressure. For example, the system controller 128 provides the foreline pressure system controller 144 with a first target setpoint corresponding to a first time or phase of the process being performed in the processing chamber 100. The initial response to the control pressure may be to provide a voltage signal to the throttle valve 246 of the actuator 248. If the target setpoint pressure is not achieved, the foreline pressure system controller 144 may then initiate a voltage signal to the mass flow controller 346 to inject a determined amount of gas into the foreline 130. In another embodiment, the mass flow controller is first utilized to vary the foreline pressure, followed by the regulator valve as needed. In yet another embodiment, a regulator valve stem position indicator is utilized.

[0034]

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

[0035]

[0040] FIG. 5 shows an exemplary schematic diagram of a network 550 of processing chambers 500. Although the example shown in FIG. 5 shows three processing chambers 500a, 500b, and 500c, the network 550 may comprise one or more processing chambers 500 coupled to a common foreline 560. In one embodiment, each processing chamber 500a, 500b, and 500c of the network 550 of processing chambers 500 is coupled to the common foreline 130 by a respective one of foreline segments 530a, 530b, and 530c. Although FIG. 5 shows independent foreline pressure control systems 540a, 540b, and 540c, each foreline 530a, 530b, and 530c may be coupled together upstream of a single foreline pressure control system. 5 shows a common optional pre-pump removal system 534, foreline pump 536, and optional exhaust treatment device 532, there may be a separate optional pre-pump removal system 534, foreline pump 536, and optional exhaust treatment device 532 for each processing chamber 500a, 500b, 500c in the network 550 of processing chambers 500. In another embodiment, the processing chambers 500a, 500b, and 500c are connected in parallel to a single foreline pressure control system and multiple downstream devices, for example, one path may be the optional pre-pump removal system 534, foreline pump 536, and another path may be the foreline pump 536 and optional exhaust treatment device 532.

[0036]

[0041] The processing chambers 500a, 500b, and 500c may experience pressure fluctuations during normal processing operations. Each processing chamber 500a, 500b, and 500c is regulated by an independent system controller 528a, 528b, and 528c, which communicates with a respective foreline pressure control system 544a, 544b, and 544c to regulate the pressure within the forelines 530a, 530b, and 530c. In one embodiment, the system controllers 528a, 528b, and 528c are operable to maintain pressure fluctuations within each processing chamber 500a, 500b, and 500c below 50 mTorr. Accordingly, embodiments of the foreline pressure control systems 544a, 544b, and 544c may be configured in any combination as shown in FIGS. 2, 3, or 4 to control the pressure within the foreline 530a, 530b, and 530c architectures.

[0037]

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

[0038]

[0043] In operation 620, the measured first foreline pressure is compared to a first foreline pressure setpoint by the foreline pressure control system. The first foreline pressure setpoint 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 setpoint from a system controller that controls the operation of the processing system. The first foreline pressure setpoint may be associated with a particular stage or time of a substrate process being performed in the processing system. In some embodiments, multiple foreline pressure setpoints are provided collectively or over time from the system controller to the foreline pressure control system, where each foreline pressure setpoint is associated with a different time or stage of a substrate process being performed in the processing system. Different times or stages of a substrate process being performed in the processing system may result in different pressures in the processing chamber.

[0039]

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

[0040]

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

[0041]

[0046] Thus, a method and system are disclosed for controlling pressure in the foreline independently of the operation of the pump and throttle valve connected immediately downstream of the chamber exhaust. The foreline pressure control system reduces pressure fluctuations both within the foreline and within the processing chamber. The foreline pressure control system accommodates setpoint changes at various stages of substrate processing, enabling improved process uniformity, increased yield, reduced waste, improved processing efficiency, and reduced cost of ownership.

[0042]

[0047] While the above description is directed to embodiments of the present disclosure, other and further embodiments of the disclosure may be devised without departing from the basic scope thereof, the scope of which is determined by the claims that follow.

Claims

1. 1. A processing system comprising a controller, the controller comprising: determining a first foreline pressure at a first time in a foreline downstream of a first pump coupled to an exhaust outlet of a first processing chamber; comparing the determined first foreline pressure to a first set point; commanding a first pressure control system associated with the foreline downstream of the first pump to adjust the first foreline pressure based on a comparison between the determined first foreline pressure and the first setpoint; a processing system configured to:

2. the first pressure control system: a foreline pressure system controller configured to receive the first setpoint from a system controller configured to control operation of the first processing chamber; The processing system of claim 1 , comprising:

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

4. The treatment system of claim 3 , wherein the foreline pressure regulation device comprises a regulator valve disposed in the foreline.

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

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

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

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

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

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

11. 3. 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 various stages of a process performed in the processing chamber.

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

13. the first processing chamber coupled to the controller; a first pump having an inlet and an outlet, the inlet of the first pump being coupled to the outlet of the first processing chamber and the outlet of the first pump being coupled to the foreline; a first foreline pressure control system in fluid communication with the foreline downstream of the first pump, the first foreline pressure control system operable to control pressure within the foreline independently of operation of the first pump; The processing system of claim 1 further comprising:

14. a removal system in fluid communication with the foreline downstream of the first foreline pressure control system; The processing system of claim 13 further comprising:

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

16. a second foreline pressure control system coupled to the second feed section, the second foreline pressure control system operable to control pressure within the second feed section independently of the first foreline pressure control system; The processing system of claim 15 further comprising:

17. 10. The processing system of claim 1, further comprising: a first pressure control system, wherein the first pressure control system comprises a pressure sensor, a regulator valve, and a foreline pressure system controller; and a second pressure control system comprises a mass flow controller, a gas source, and a gas injection port.

18. 1. A processing system comprising: a first processing chamber having an exhaust port; a first pump having an inlet coupled to the exhaust of the first processing chamber and an exhaust coupled to an inlet of a first foreline segment; a second processing chamber having an exhaust port; a second pump having an inlet connected to the exhaust of the second processing chamber and an exhaust connected to the inlet of a second foreline segment; a foreline coupled to the exhaust ports of the first foreline segment and the second foreline segment; a first pressure control system associated with the first foreline segment; a second pressure control system associated with the second foreline segment; wherein the first pressure control system is operable to control the pressure in the first foreline segment independently of operation of a first pump and a second pump, and the second pressure control system is operable to control the pressure in the second foreline segment independently of control of the pressure in the first foreline.

19. a removal system in fluid communication with the foreline; The processing system of claim 18 further comprising:

20. 1. A method for controlling pressure in a processing system, comprising: measuring a first foreline pressure downstream of a first pump coupled to an exhaust outlet of a first processing chamber at a first time; comparing the measured first foreline pressure to a first set point; adjusting the first foreline pressure by a first pressure control system associated with the foreline downstream of the first pump based on a comparison between the measured first foreline pressure and the first set point; A method comprising:

21. adjusting the first foreline pressure; throttling a control valve or injecting gas into the foreline based on the comparison.

21. The method of claim 20, further comprising:

22. measuring a second foreline pressure downstream of a second pump coupled to an exhaust of the second processing chamber; comparing the measured second foreline pressure to a second set point; adjusting the second foreline pressure by a second pressure control system associated with the foreline downstream of the second pump based on a comparison between the measured second foreline pressure and the second set point; 21. The method of claim 20, further comprising:

23. 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; adjusting the second foreline pressure by a second pressure control system based on a comparison between the measured second foreline pressure and the second set point; 21. The method of claim 20, further comprising: wherein the first set point is based on a first stage of a process being performed in the first processing chamber and the second set point is based on a second stage of the process being performed in a second processing chamber.

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