Parallel precursor delivery system with flow ratio control

Abstract

The present disclosure provides precursor delivery system having a carrier gas flow path, a precursor vessel containing a precursor in fluid communication with the carrier gas flow path, and a concentration monitor configured to measure a concentration of a precursor / carrier gas mixture formed in the precursor vessel. A first and second carrier gas mass flow controller, positioned in parallel, are configured to receive a portion of the carrier gas flow, and a first and a second precursor / carrier gas mass flow controller, positioned in parallel, are configured to receive a portion of the precursor / carrier gas mixture. The outputs of the first carrier gas mass flow controller and first precursor / carrier gas mass flow controller are combined to form a first delivery output, and the outputs of the second carrier gas mass flow controller and second precursor / carrier gas mass flow controller are combined to form a second delivery output.

Description

Docket Number: 00790-WOPARALLEL PRECURSOR DELIVERY SYSTEM WITH FLOW RATIO CONTROLFIELD OF THE INVENTION

[0001] The present disclosure relates to precursor delivery systems for semiconductor manufacturing, and more particularly to embodiments of a parallel precursor delivery system with flow ratio control for improved low vapor pressure precursor delivery.BACKGROUND

[0002] In semiconductor manufacturing, precursor delivery systems play a crucial role in transporting chemical substances to processing chambers for deposition processes such as chemical vapor deposition (CVD) and atomic layer deposition (ALD). These systems are responsible for delivering precise amounts of precursor materials, typically in gaseous or vaporized liquid form, to create thin fdms or deposit specific materials onto semiconductor wafers.

[0003] Precursor delivery systems often utilize carrier gases to transport the precursor materials from storage vessels to the processing chambers. The concentration and flow rate of precursors in the carrier gas stream are carefully controlled to achieve desired deposition characteristics. Accurate control of precursor delivery is essential for maintaining consistency and quality in semiconductor device fabrication.

[0004] Conventional precursor delivery systems may employ various components such as mass flow controllers, pressure regulators, and concentration monitors to manage the flow and composition of precursor-carrier gas mixtures. These systems aim to provide stable and reproducible precursor delivery to one or more processing chambers.

[0005] As semiconductor manufacturing processes become more complex and demanding, there is an ongoing need for improved precursor delivery systems. Challenges in precursor delivery include maintaining precise control over gas mixture compositions, accommodating multiple precursors and processing chambers, and optimizing system efficiency.

[0006] Additionally, some precursor materials used in semiconductor manufacturing have low vapor pressures, which can present difficulties in achieving consistent delivery rates. Low vapor pressure precursors may require special handling and delivery techniques to ensure adequate material transport to the processing chambers.

[0007] Efforts to enhance precursor delivery systems often focus on improving flow control, increasing flexibility in gas mixture compositions, and accommodating multiple process requirements. These improvements can contribute to advancements in semiconductor device fabrication by enabling more precise and versatile deposition processes.Docket Number: 00790-WOSUMMARY

[0008] This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the detailed description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.

[0009] According to an aspect of the present disclosure, a precursor delivery system is provided. The precursor delivery system includes at least one carrier gas flow. The system includes at least one precursor vessel containing at least one precursor, the precursor vessel in fluid communication with at least a portion of the carrier gas flow. At least one precursor / carrier gas mix is formed by flowing at least a portion of the at least one carrier gas flow within the at least one precursor within the at least one precursor vessel. The system includes at least one concentration monitor in fluid communication with the at least one pressure vessel, the concentration monitor configured to measure a concentration of the at least one precursor / carrier gas mix. The system further includes a first carrier gas mass flow controller and at least a second carrier gas mass flow controller, the first and second carrier gas mass flow controllers positioned in parallel and configured to equally receive at least a portion of the at least one carrier gas flow. Additionally, the system includes a first precursor / carrier gas mass flow controller and at least a second precursor / carrier gas mass flow controller, the first and second precursor / carrier gas mass flow controllers positioned in parallel and configured to equally receive the at least a portion of the at least one precursor / carrier gas mix. An output of the first carrier gas mass flow controller and an output of the first precursor / carrier gas mass flow controller is combined to form a first output. An output of the second carrier gas mass flow controller and an output of the second precursor / carrier gas mass flow controller is combined to form a second output.

[0010] According to another aspect of the present disclosure, a method of controlling precursor delivery is provided. Specifically, the method includes the steps creating a carrier gas flow within a precursor delivery system. A portion of the carrier gas is directed into at least one precursor vessel containing at least one precursor to form at least one precursor / carrier gas mixture. Thereafter, a concentration of the at least one precursor / carrier gas mixture is measured using at least one concentration monitor. The carrier gas flow is split into parallel paths through a first carrier gas mass flow controller and a second carrier gas mass flow controller. The precursor / carrier gas mixture flow is split into parallel paths through a first precursor / carrier gas mass flow controller and a second precursor / carrier gas mass flow controller. The output of the first carrier gas mass flow controller and an output of the first precursor / carrier gas mass flow controller are combined to form a first delivery output, and the output of the second carrier gas mass flow controller and an output of the second precursor / carrier gas mass flow controller are combined to form a second delivery output.

[0011] According to another aspect of the present disclosure, a semiconductor processing system is disclosed. The system includes a precursor delivery system including a carrier gas source, at least one precursor vessel containing at least one precursor, and at least one concentration monitorDocket Number: 00790-WOconfigured to measure a concentration of a precursor / carrier gas mixture formed in the precursor vessel. Parallel carrier gas mass flow controllers configured to receive carrier gas from the carrier gas source. Similarly, parallel precursor / carrier gas mass flow controllers configured to receive the precursor / carrier gas mixture. The system further includes at least one controller configured to regulate flow through the parallel carrier gas mass flow controllers and the parallel precursor / carrier gas mass flow controllers based on concentration data from the concentration monitor, and combine outputs from one carrier gas mass flow controller and one precursor / carrier gas mass flow controller to form each of multiple delivery outputs.

[0012] The foregoing general description of the illustrative embodiments and the following detailed description thereof are merely exemplary aspects of the teachings of this disclosure and are not restrictive.BRIEF DESCRIPTION OF THE FIGURES

[0013] The drawings disclose illustrative embodiments and are not intended to set forth all embodiments of the methods and apparatus for flow ratio control of precursor delivery systems. Details that may be apparent or unnecessary may be omitted to save space or for more effective illustration. Conversely, some embodiments may be practices without all the detailed disclosed with regard to specific embodiments. When the same reference numbers appear in different drawings, the reference numbers refer to same or similar components or steps. The novel aspects of the methods and devices described herein will become more apparent by consideration of the following figures, wherein:

[0014] Figure 1 shows a schematic diagram of an embodiment of a precursor delivery system employing parallel mass flow controllers; and

[0015] Figure 2 shows a schematic diagram of another embodiment of a precursor delivery system employing parallel mass flow controllers.DETAILED DESCRIPTION

[0016] The following description sets forth exemplary aspects of the present disclosure. It should be recognized, however, that such description is not intended as a limitation on the scope of the present disclosure. Rather, the description also encompasses combinations and modifications to those exemplary aspects described herein.

[0017] The present disclosure relates to methods and apparatus for flow ratio control of precursor delivery systems. In particular, the disclosure describes various configurations of parallel precursor delivery systems that provide improved control over precursor flow and concentration in semiconductor manufacturing processes.Precursor delivery systems play a crucial role in semiconductor fabrication, transporting chemical substances to processing chambers for deposition processes such as chemical vapor deposition (CVD)Docket Number: 00790-WOand atomic layer deposition (ALD). The systems described herein offer solutions for precisely controlling and splitting precursor gas mixtures for delivery to multiple chambers or zones without compromising precursor concentration or system pressure.

[0018] The parallel precursor delivery systems disclosed may incorporate multiple mass flow controllers arranged in parallel configurations. This arrangement allows for independent control of carrier gas flows and precursor / carrier gas mixture flows. By utilizing parallel flow paths, the systems can maintain desired precursor concentrations while providing flexibility in flow distribution to different processing chambers.

[0019] In some cases, the parallel precursor delivery systems may include concentration monitoring capabilities to measure and regulate precursor concentrations in real-time. The systems may also incorporate pressure control devices to manage carrier gas pressures entering precursor vessels.

[0020] The disclosed configurations aim to address limitations of prior art systems by enabling precise flow ratio control without necessitating increased upstream pressures that could negatively impact precursor concentrations. These systems may provide enhanced flexibility in delivering varying precursor concentrations and flow rates to multiple processing chambers simultaneously.

[0021] The precursor delivery system 200 shown in Figure 1 may include a carrier gas input 202 configured to provide a carrier gas flow 204 to the system. In some cases, the carrier gas input 202 may supply a carrier gas comprising nitrogen. Alternatively, the carrier gas may comprise argon, helium, or hydrogen.

[0022] As shown in Figure 1, the carrier gas flow 204 may be split into multiple paths within the precursor delivery system 200. A split carrier gas flow 206 may be directed to a pressure control device 208, while another portion of the carrier gas flow 204 may be directed to one or more mass flow controllers.

[0023] Referring to Figure 2, a similar configuration may be employed in the precursor delivery system 300. A carrier gas input 302 may provide a carrier gas flow 304 to the system. The carrier gas flow 304 may be divided, with a split carrier gas flow 306 directed to multiple pressure controllers 308a, 308b. The remaining portion of the carrier gas flow 304 may be routed to one or more carrier gas mass flow controllers.

[0024] In some cases, the splitting of the carrier gas flow may allow for independent control of carrier gas pressure and flow rate in different parts of the precursor delivery system. This configuration may provide flexibility in managing precursor concentration and overall gas flow within the system.

[0025] As shown in Figure 1, the precursor delivery system 200 may include a precursor vessel 210 containing a precursor material 212. In some cases, the precursor vessel 210 may be in fluidDocket Number: 00790-WOcommunication with a pressure control device 208. The pressure control device 208 may be configured to regulate the pressure of carrier gas flowing into the precursor vessel 210.

[0026] In some implementations, as shown in Figure 2, the precursor delivery system 300 may include a first precursor vessel 310a and a second precursor vessel 310b. The first precursor vessel 310a may contain a first precursor material 312a, while the second precursor vessel 310b may contain a second precursor material 312b. The first and second precursor materials 312 may be different chemical substances used in semiconductor manufacturing processes.

[0027] A first pressure controller 308a may be associated with the first precursor vessel 310a, and a second pressure controller 308b may be associated with the second precursor vessel 310b. These pressure controllers 308a, 308b may regulate the pressure of carrier gas flowing into their respective precursor vessels 310a, 310b.

[0028] In some cases, the pressure of carrier gas flowing into the first precursor vessel 310a and the second precursor vessel 310b may be the same. In other cases, the pressure of carrier gas flowing into the first precursor vessel 310a may be different from the pressure of carrier gas flowing into the second precursor vessel 310b. This flexibility in pressure control may allow for optimization of precursor delivery based on the specific properties of each precursor material 312 and the requirements of the semiconductor manufacturing process.

[0029] In some cases, the precursor delivery system 200 of Figure 1 may be configured to form a precursor carrier gas mixture 214 within the precursor vessel 210. The split carrier gas flow 206 from the pressure control device 208 may be directed into the precursor vessel 210 containing the precursor material 212. As the split carrier gas flow 206 passes through the precursor vessel 210, the carrier gas may interact with the precursor material 212, resulting in the formation of the precursor carrier gas mixture 214.

[0030] Referring to Figure 2, the precursor delivery system 300 may be configured to form multiple precursor carrier gas mixtures simultaneously. The split carrier gas flow 306 may be directed to the first pressure controller 308a and the second pressure controller 308b. In some cases, the first pressure controller 308a may regulate the pressure of the carrier gas flowing into the first precursor vessel 310a, while the second pressure controller 308b may regulate the pressure of the carrier gas flowing into the second precursor vessel 310b.

[0031] As the carrier gas flows through the first precursor vessel 310a, a first precursor gas mixture 314a may be formed. Similarly, as the carrier gas flows through the second precursor vessel 310b, a second precursor gas mixture 314b may be formed. In some cases, the concentrations of precursor within the first precursor gas mixture 314a and the second precursor gas mixture 314b may be the same. In other cases, the concentrations may be different, providing flexibility in precursor delivery to different processing chambers or zones.Docket Number: 00790-WO

[0032] The precursor carrier gas mixtures formed in the precursor vessels may then flow to their respective concentration monitors. For example, in Figure 1, the precursor carrier gas mixture 214 may flow to the concentration monitor 216. In Figure 2, the first precursor gas mixture 314a may flow to the first concentration monitor 316a, while the second precursor gas mixture 314b may flow to the second concentration monitor 316b.

[0033] Referring to Figure 1, the precursor delivery system 200 may include a concentration monitor 216 configured to measure the concentration of precursor within a precursor / carrier gas mixture 214. In some cases, the concentration monitor 216 may be in fluid communication with the precursor vessel 210. The concentration monitor 216 may be positioned downstream of the precursor vessel 210 to receive the precursor / carrier gas mixture 214 flowing from the precursor vessel 210.

[0034] In some implementations, the concentration monitor 216 may be configured to provide concentration data 218 to a delivery system controller 220. The concentration data 218 may represent real-time measurements of the precursor concentration within the precursor / carrier gas mixture 214. This communication between the concentration monitor 216 and the delivery system controller 220 may allow for continuous monitoring and adjustment of precursor concentrations within the precursor delivery system 200.

[0035] Referring to Figure 2, the precursor delivery system 300 may include a first concentration monitor 316a and a second concentration monitor 316b. The first concentration monitor 316a may be associated with the first precursor vessel 310a, while the second concentration monitor 316b may be associated with the second precursor vessel 310b. In some cases, the first concentration monitor 316a may be configured to measure the concentration of a first precursor gas mixture 314a flowing from the first precursor vessel 310a. Similarly, the second concentration monitor 316b may be configured to measure the concentration of a second precursor gas mixture 314b flowing from the second precursor vessel 310b.

[0036] The first concentration monitor 316a may be configured to provide first concentration data 318a to a system controller 320. Likewise, the second concentration monitor 316b may be configured to provide second concentration data 318b to the system controller 320. This configuration may allow for independent monitoring and control of multiple precursor concentrations within the precursor delivery system 300.

[0037] In some implementations, the system controller 320 may use the first concentration data 318a and the second concentration data 318b to make adjustments to various components of the precursor delivery system 300. For example, the system controller 320 may adjust the settings of the first pressure controller 308a or the second pressure controller 308b based on the received concentration data. This feedback mechanism may help maintain desired precursor concentrations throughout the operation of the precursor delivery system 300.Docket Number: 00790-WO

[0038] As shown in Figure 1, the precursor delivery system 200 may include a delivery system controller 220 configured to manage various components and operations within the system. In some cases, the delivery system controller 220 may be in communication with the concentration monitor 216. The concentration monitor 216 may provide concentration data 218 to the delivery system controller 220, allowing the delivery system controller 220 to monitor and potentially adjust the concentration of precursor within the precursor carrier gas mixture 214.

[0039] In some implementations, the delivery system controller 220 may generate and distribute control signals to various components of the precursor delivery system 200. For example, the delivery system controller 220 may output a first control signal 222 to the first carrier gas controller 226 and a second control signal 222' to the second carrier gas controller 228. These control signals may allow the delivery system controller 220 to regulate the flow of carrier gas through the respective mass flow controllers.

[0040] Referring to Figure 2, the precursor delivery system 300 may include a system controller 320 that performs similar functions to the delivery system controller 220 described in Figure 1. The system controller 320 may generate a control signal 322 that is distributed to various components within the precursor delivery system 300. In some cases, the system controller 320 may receive a monitor output signal 324 from the first concentration monitor 316a and the second concentration monitor 316b, providing information about the concentrations of precursors in the respective precursor gas mixtures.

[0041] The delivery system controller 220 (See Figure 1) and the system controller 320 (See Figure 2) may be configured to selectively adjust the concentration of precursor within the precursor carrier gas mixture. This adjustment may be based on the concentration data received from the concentration monitors. For example, if the concentration of precursor in the precursor carrier gas mixture 214 is lower than desired, the delivery system controller 220 may adjust the control signals sent to the carrier gas controllers or the pressure control device 208 precursor gas controllers to increase the concentration.

[0042] In some cases, the carrier gas mass flow controllers and precursor / carrier gas mass flow controllers may be in communication with external controllers, such as process chamber controllers. This communication may allow for coordination between the precursor delivery system and the processing chambers, ensuring that the appropriate precursor concentrations and flow rates are maintained for specific semiconductor manufacturing processes.

[0043] The system controllers may also manage the operation of multiple precursor vessels and their associated components. For instance, in the precursor delivery system 300 shown in Figure 3, the system controller 320 may independently control the first pressure controller 308a and the second pressure controller 308b to manage the carrier gas flow into the first precursor vessel 310a and the second precursor vessel 310b, respectively. This independent control may allow for the generation ofDocket Number: 00790-WOprecursor gas mixtures with different concentrations or compositions, providing flexibility in precursor delivery to different processing chambers or zones.

[0044] As shown in Figure 1, the precursor delivery system 200 may include a first carrier gas controller 226 and a second carrier gas controller 228. In some cases, the first carrier gas controller 226 and the second carrier gas controller 228 may be positioned in parallel and configured to receive the carrier gas flow 204. The parallel arrangement of the first carrier gas controller 226 and the second carrier gas controller 228 may allow for independent control of carrier gas flow to different parts of the precursor delivery system 200.

[0045] In some implementations, the precursor delivery system 200 may also include a first precursor / carrier gas controller 230 and a second precursor / carrier gas controller 232. The first precursor / carrier gas controller 230 and the second precursor / carrier gas controller 232 may be positioned in parallel and configured to receive the precursor carrier gas mixture 214 from the concentration monitor 216. This parallel configuration of the first precursor / carrier gas controller 230 and the second precursor / carrier gas controller 232 may enable independent control of precursor / carrier gas mixture flow to different processing chambers or zones.

[0046] Referring to Figure 2, the precursor delivery system 300 may incorporate a similar parallel arrangement of mass flow controllers. The precursor delivery system 300 may include a first carrier gas controller 326a and a second carrier gas controller 326b positioned in parallel. In some cases, the first carrier gas controller 326a and the second carrier gas controller 326b may be configured to receive and regulate the carrier gas flow 304.

[0047] The precursor delivery system 300 may also include a first precursor / carrier flow controller 328a and a second precursor / carrier flow controller 328b positioned in parallel. In some implementations, the first precursor / carrier flow controller 328a and the second precursor / carrier flow controller 328b may be configured to receive and regulate the first precursor gas mixture 314a from the first concentration monitor 316a.

[0048] Additionally, the precursor delivery system 300 may include a third precursor / carrier flow controller 332a and a fourth precursor / carrier flow controller 332b positioned in parallel. The third precursor / carrier flow controller 332a and the fourth precursor / carrier flow controller 332b may be configured to receive and regulate the second precursor gas mixture 314b from the second concentration monitor 316b.

[0049] In some cases, the parallel arrangement of the carrier gas controllers and precursor flow controllers may allow for flexible and independent control of gas flows within the precursor delivery system 300. This configuration may enable the delivery of different precursor concentrations or flow rates to multiple processing chambers simultaneously.

[0050] The delivery system controller 220 (See Figure 2) or the system controller 320 (See Figure 3) may be in communication with the parallel mass flow controllers. In some implementations,Docket Number: 00790-WOthe delivery system controller 220 or the system controller 320 may send control signals to adjust the flow rates of the parallel mass flow controllers based on the concentration data received from the concentration monitors. This feedback mechanism may allow for precise control of precursor concentrations and flow rates throughout the precursor delivery system.

[0051] In some cases, the precursor delivery system 200 may include multiple mass flow controllers configured to regulate the flow of carrier gas and precursor / carrier gas mixtures. As shown in Figure 1, the first carrier gas controller 226 may output a first regulated carrier flow 240, while the second carrier gas controller 228 may output a second regulated carrier flow 244. These regulated carrier flows may be independently controlled based on the first control signal 222 and the second control signal 222' received from the delivery system controller 220.

[0052] The precursor delivery system 200 may also include mass flow controllers for regulating the flow of precursor / carrier gas mixtures. In some implementations, a first precursor / carrier gas controller 230 may output a first regulated precursor flow 242, while a second precursor / carrier gas controller 232 may output a second regulated precursor flow 246. The first regulated precursor flow 242 and the second regulated precursor flow 246 may be derived from the precursor carrier gas mixture 214 that has passed through the concentration monitor 216.

[0053] In some cases, the regulated flows from the carrier gas controllers and precursor gas controllers may be combined to form final delivery outputs. For example, the first regulated carrier flow 240 from the first carrier gas controller 226 may be combined with the first regulated precursor flow 242 from the first precursor / carrier gas controller 230 to form a first delivery output 250.Similarly, the second regulated carrier flow 244 from the second carrier gas controller 228 may be combined with the second regulated precursor flow 246 from the second precursor / carrier gas controller 232 to form a second delivery output 252.

[0054] Referring to Figure 2, the precursor delivery system 300 may employ a similar configuration with additional regulated flows. The first carrier gas controller 326a may output a first regulated carrier flow 336, while a first precursor / carrier flow controller 328a may output a first regulated precursor flow 338. In some cases, a third precursor / carrier flow controller 332a may output a third regulated precursor flow 340. These regulated flows may be combined to form a first chamber output 360.

[0055] The precursor delivery system 300 may also include a second carrier gas controller 326b that outputs a second regulated carrier flow 350. A second precursor / carrier flow controller 328b may output a second regulated precursor flow 352, and a fourth precursor / carrier flow controller 332b may output a fourth regulated precursor flow 354. These regulated flows may be combined to form a second chamber output 362.

[0056] In some implementations, the regulated flows and their combinations may be controlled by the system controller 320 based on the concentration data received from the first concentrationDocket Number: 00790-WOmonitor 316a and the second concentration monitor 316b. This configuration may allow for precise control of precursor concentrations and flow rates in the final delivery outputs, which may be directed to different processing chambers or zones within a semiconductor manufacturing system.

[0057] In some cases, the precursor delivery system 200 of Figure 1 may be configured to produce multiple outputs for delivery to one or more processing chambers. The first carrier gas controller 226 may output a first regulated carrier flow 240, while the first precursor / carrier gas controller 230 may output a first regulated precursor flow 242. In some implementations, the first regulated carrier flow 240 and the first regulated precursor flow 242 may be combined to form a first delivery output 250. The first delivery output 250 may be directed to a processing chamber for use in semiconductor manufacturing processes.

[0058] Similarly, the second carrier gas controller 228 may output a second regulated carrier flow 244, and the second precursor / carrier gas controller 232 may output a second regulated precursor flow 246. In some cases, the second regulated carrier flow 244 and the second regulated precursor flow 246 may be combined to form a second delivery output 252. The second delivery output 252 may be directed to the same processing chamber as the first delivery output 250 or to a different processing chamber.

[0059] Referring to Figure 2, the precursor delivery system 300 may be configured to provide multiple outputs with different precursor compositions. The first carrier gas controller 326a may output a first regulated carrier flow 336. The first precursor / carrier flow controller 328a may output a first regulated precursor flow 338, while the third precursor / carrier flow controller 332a may output a third regulated precursor flow 340. In some implementations, the first regulated carrier flow 336, the first regulated precursor flow 338, and the third regulated precursor flow 340 may be combined to form a first chamber output 360.

[0060] The second carrier gas controller 326b may output a second regulated carrier flow 350. The second precursor / carrier flow controller 328b may output a second regulated precursor flow 352, and the fourth precursor / carrier flow controller 332b may output a fourth regulated precursor flow 354. In some cases, the second regulated carrier flow 350, the second regulated precursor flow 352, and the fourth regulated precursor flow 354 may be combined to form a second chamber output 362.

[0061] The first chamber output 360 and the second chamber output 362 may be directed to different processing chambers or different zones within a single processing chamber. In some implementations, the composition and flow rates of the first chamber output 360 and the second chamber output 362 may be independently controlled by adjusting the settings of their respective mass flow controllers.

[0062] The system controller 320 may be configured to manage the composition and flow rates of the first chamber output 360 and the second chamber output 362 based on the concentration data received from the first concentration monitor 316a and the second concentration monitor 316b. ThisDocket Number: 00790-WOconfiguration may allow for precise control of precursor delivery to multiple processing chambers or zones, potentially enabling simultaneous deposition processes with different precursor requirements.

[0063] In some cases, the parallel arrangement of mass flow controllers in the precursor delivery system 300 may allow for flexible adjustment of precursor concentrations and flow rates in the first chamber output 360 and the second chamber output 362 without affecting the upstream pressure in the precursor vessels. This configuration may help maintain consistent precursor concentrations while providing the ability to deliver different precursor mixtures to multiple processing chambers or zones.

[0064] In some cases, a parallel precursor delivery system may be configured to operate with multiple precursor vessels, concentration monitors, and mass flow controllers to create multiple parallel precursor / carrier gas circuits. The parallel precursor delivery system may provide flexible and precise control over precursor delivery to multiple processing chambers or zones.

[0065] The parallel precursor delivery system of Figure 1 may begin operation when the carrier gas input 202 supplies a carrier gas flow 204 to the system. The carrier gas flow 204 may be split, with a portion directed as the split carrier gas flow 206 to the pressure control device 208. The pressure control device 208 may regulate the pressure of the carrier gas entering the precursor vessel 210.

[0066] In the precursor vessel 210, the carrier gas may interact with the precursor material 212 to form the precursor carrier gas mixture 214. The precursor carrier gas mixture 214 may then flow to the concentration monitor 216. The concentration monitor 216 may measure the concentration of precursor in the mixture and provide concentration data 218 to the delivery system controller 220.

[0067] Based on the concentration data 218, the delivery system controller 220 may generate control signals to adjust the flow rates of various components. For example, the delivery system controller 220 may send a first control signal 222 to the first carrier gas controller 226 and a second control signal 222' to the second carrier gas controller 228.

[0068] The first carrier gas controller 226 and the second carrier gas controller 228 may regulate the flow of pure carrier gas, outputting the first regulated carrier flow 240 and the second regulated carrier flow 244, respectively. Simultaneously, the first precursor / carrier gas controller 230 and the second precursor / carrier gas controller 232 may regulate the flow of the precursor carrier gas mixture, producing the first regulated precursor flow 242 and the second regulated precursor flow 246.

[0069] The system may then combine these regulated flows to create the final outputs. The first regulated carrier flow 240 may be combined with the first regulated precursor flow 242 to form the first delivery output 250. Similarly, the second regulated carrier flow 244 may be combined with the second regulated precursor flow 246 to form the second delivery output 252.

[0070] In some implementations, the parallel precursor delivery system may incorporate additional precursor vessels and associated components to create multiple parallel circuits. For example, the precursor delivery system 300 of Figure 2 may include a first precursor vessel 310a andDocket Number: 00790-WOa second precursor vessel 310b, each containing a precursor material 312. The split carrier gas flow 306 may be directed to both the first pressure controller 308a and the second pressure controller 308b, which regulate the carrier gas flow into their respective precursor vessels.

[0071] The first precursor vessel 310a may produce a first precursor gas mixture 314a, while the second precursor vessel 310b may produce a second precursor gas mixture 314b. These mixtures may flow to the first concentration monitor 316a and the second concentration monitor 316b, respectively. The concentration monitors may provide first concentration data 318a and second concentration data 318b to the system controller 320.

[0072] Based on the received concentration data, the system controller 320 may generate control signals to adjust the flow rates of various components. The system controller 320 may send control signals to the first carrier gas controller 326a, second carrier gas controller 326b, first precursor / carrier flow controller 328a, second precursor / carrier flow controller 328b, third precursor / carrier flow controller 332a, and fourth precursor / carrier flow controller 332b.

[0073] These controllers may regulate their respective flows, producing the first regulated carrier flow 336, second regulated carrier flow 350, first regulated precursor flow 338, second regulated precursor flow 352, third regulated precursor flow 340, and fourth regulated precursor flow 354.

[0074] The system may then combine these regulated flows to create the final outputs. The first regulated carrier flow 336, first regulated precursor flow 338, and third regulated precursor flow 340 may be combined to form the first chamber output 360. Similarly, the second regulated carrier flow 350, second regulated precursor flow 352, and fourth regulated precursor flow 354 may be combined to form the second chamber output 362.

[0075] In some cases, the parallel precursor delivery system may be expanded to include additional precursor vessels, concentration monitors, and mass flow controllers, creating multiple parallel precursor / carrier gas circuits. This configuration may allow for the delivery of various precursor mixtures with independently controlled concentrations and flow rates to multiple processing chambers or zones simultaneously.

[0076] A number of implementations have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the disclosure. Accordingly, other implementations are within the scope of the following claims.

Claims

Docket Number: 00790-WOClaims1. A precursor delivery system (200) comprising:a carrier gas flow path (204);a precursor vessel (210) containing a precursor (212) and in fluid communication with the carrier gas flow path (204); anda concentration monitor (216) configured to measure a concentration of a precursor / carrier gas mixture (214) formed in the precursor vessel (210);characterized in that the system comprises a first carrier gas mass flow controller (226) and a second carrier gas mass flow controller (228) positioned in parallel and configured to receive a portion of the carrier gas flow, and a first precursor / carrier gas mass flow controller (230) and a second precursor / carrier gas mass flow controller (232) positioned in parallel and configured to receive a portion of the precursor / carrier gas mixture (214), wherein an output of the first carrier gas mass flow controller (226) and an output of the first precursor / carrier gas mass flow controller (230) are combined to form a first delivery output (250), and an output of the second carrier gas mass flow controller (228) and an output of the second precursor / carrier gas mass flow controller (232) are combined to form a second delivery output (252).

2. The precursor delivery system of claim 1, further comprising a pressure control device (208) configured to regulate a pressure of carrier gas flowing into the precursor vessel (210).

3. The precursor delivery system of claim 2, wherein the pressure control device (208) is positioned upstream of the precursor vessel (210) in the carrier gas flow path (204).

4. The precursor delivery system of any preceding claim, wherein the concentration monitor (216) is disposed downstream of the precursor vessel (210) and is configured to output concentration data (218) representative of the concentration of the precursor / carrier gas mixture (214).

5. The precursor delivery system of any preceding claim, further comprising a system controller (220) in communication with the concentration monitor (216) and the mass flow controllers (226, 228, 230, 232), the system controller (220) being configured to regulate flow through the parallel mass flow controllers based on the concentration data (218) to maintain a target precursor concentration and / or a predetermined flow ratio between precursor / carrier gas mixture and carrier gas at each of the first and second delivery outputs (250, 252).

6. The precursor delivery system of any preceding claim, wherein the first delivery output (250) and the second delivery output (252) are configured to be directed to different processing chambers and / orDocket Number: 00790-WOdifferent zones of a processing chamber, with independently controllable precursor concentrations and total flow rates.

7. The precursor delivery system of any preceding claim, wherein the mass flow controllers positioned in parallel are configured to receive their respective portions of flow from a common manifold such that each parallel path is independently settable while maintaining a substantially constant upstream pressure at the precursor vessel (210).

8. The precursor delivery system of any preceding claim, wherein the system controller (220) is configured to implement closed-loop feedback using the concentration data (218) to adjust setpoints of at least one of the carrier gas mass flow controllers (226, 228) and the precursor / carrier gas mass flow controllers (230, 232) without increasing vessel pressure to compensate for concentration drift.

9. The precursor delivery system of any preceding claim, wherein the carrier gas comprises nitrogen, argon, helium and / or hydrogen.

10. The precursor delivery system of any preceding claim, wherein the precursor comprises a low vapor pressure precursor.

11. A method of controlling precursor delivery in a precursor delivery system (200), the method comprising creating a carrier gas flow (204); flowing a portion of the carrier gas into a precursor vessel (210) containing a precursor (212) to form a precursor / carrier gas mixture (214); and measuring a concentration of the precursor / carrier gas mixture (214) using a concentration monitor (216); characterized in that the method further comprises splitting the carrier gas flow into parallel paths through a first carrier gas mass flow controller (226) and a second carrier gas mass flow controller (228); splitting the precursor / carrier gas mixture into parallel paths through a first precursor / carrier gas mass flow controller (230) and a second precursor / carrier gas mass flow controller (232); combining an output of the first carrier gas mass flow controller (226) with an output of the first precursor / carrier gas mass flow controller (230) to form a first delivery output (250); and combining an output of the second carrier gas mass flow controller (228) with an output of the second precursor / carrier gas mass flow controller (232) to form a second delivery output (252).

12. The method of claim 11, further comprising regulating a pressure of the carrier gas flowing into the precursor vessel (210) using a pressure control device (208) positioned upstream of the precursor vessel (210).

13. The method of claim 11 or 12, further comprising adjusting flow rates through at least one of the parallel carrier gas mass flow controllers (226, 228) and the parallel precursor / carrier gas mass flow controllers (230, 232) based on concentration data (218) received from the concentration monitor (216).Docket Number: 00790-WO14. The method of any of claims 11 to 13, wherein the first delivery output (250) and the second delivery output (252) are directed to different processing chambers and / or different zones and are controlled to have independently settable precursor concentrations and total flow rates.

15. The method of any of claims 11 to 14, wherein maintaining a target concentration at the first and / or second delivery output (250, 252) is achieved by adjusting the parallel mass flow controllers while maintaining a substantially constant upstream pressure at the precursor vessel (210).

16. A semiconductor processing system comprising:a carrier gas source;a precursor vessel (310a, 310b) containing a precursor (312a, 312b);a concentration monitor (316a, 316b) configured to measure a concentration of a precursor / carrier gas mixture (314a, 314b) formed in the precursor vessel; andparallel carrier gas mass flow controllers (326a, 326b) configured to receive carrier gas from the carrier gas source, and parallel precursor / carrier gas mass flow controllers (328a, 328b; 332a, 332b) configured to receive the precursor / carrier gas mixture;characterized in that a controller (320) is configured to regulate flow through the parallel carrier gas mass flow controllers and the parallel precursor / carrier gas mass flow controllers based on concentration data (318a, 318b) from the concentration monitor(s), and combine outputs from one carrier gas mass flow controller and one precursor / carrier gas mass flow controller to form each of multiple delivery outputs (360, 362).

17. The semiconductor processing system of claim 16, wherein the system comprises a first precursor vessel (310a) and a second precursor vessel (310b), each having an associated concentration monitor (316a, 316b), and wherein the controller (320) is configured to form a first chamber output (360) from a combination of a regulated carrier flow (336) with regulated precursor flows (338, 340) and a second chamber output (362) from a combination of a regulated carrier flow (350) with regulated precursor flows (352, 354).

18. The semiconductor processing system of claim 16 or 17, further comprising first and second pressure controllers (308a, 308b) associated with the first and second precursor vessels (310a, 310b), respectively, the controller (320) being configured to independently adjust the pressure controllers (308a, 308b) based on the concentration data (318a, 318b).

19. The semiconductor processing system of any of claims 16 to 18, wherein the multiple delivery outputs (360, 362) are directed to different processing chambers and / or different zones and are independently controllable in precursor concentration and total flow rate.Docket Number: 00790-WO20. The semiconductor processing system of any of claims 16 to 19, wherein the controller (320) is configured to communicate with at least one process chamber controller to coordinate delivery timing, concentration setpoints and total flow setpoints for the multiple delivery outputs (360, 362).

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