Flowover vapor precursor supply

Abstract

Various embodiments relate to systems and methods for determining a precursor dose. The system may include a flow divider configured to split a carrier gas flow into a first path and a second path; an ampoule containing a precursor, a first filling volume located in the first path and a second filling volume located in the second path, and a pressure gauge configured to measure the differential pressure between (i) a first position in the first path and (ii) a second position in the second path.

Description

[Background technology]

[0001] [References] As part of this application, an application data sheet is filed concurrently with this specification. As identified in the concurrently filed application data sheet, each application to which this application claims benefit or priority is incorporated herein by reference in its entirety for any purpose.

[0002] Various semiconductor processing methods involve supplying one or more precursors to a processing chamber. In some cases, flow-over-vapor techniques are used. Such techniques are particularly useful when supplying corrosive, low-vapor-pressure precursors that may decompose or corrode when heated. The background information provided herein is intended to provide a general context for this disclosure. Any research by the inventors named at this time, as well as any other description that cannot be considered prior art at the time of filing for any other reason, within the scope described in this background information section, shall not be recognized as prior art to this disclosure, whether express or implied. [Overview of the project]

[0003] Various examples herein relate to systems and methods for determining the dose of a precursor and / or supplying it to a processing chamber. Such systems and methods are particularly useful in the context of flow-over vapor precursors. In one aspect of the disclosed example, a system is provided for supplying a dose of a precursor to a processing chamber, the system comprising: an inlet configured to allow a flow of carrier gas to enter the system; a flow divider in fluid communication with the inlet and configured to divide the flow of carrier gas into a first stream and a second stream, the first stream being supplied to a first path and the second stream being supplied to a second path; a first filling volume located in the first path through which the first stream passes, and a second filling volume located in the second path through which the second stream passes; an ampoule containing a precursor, the ampoule located in the second path, the precursor being accompanied by the second stream when the second stream passes through the ampoule at a sufficiently high temperature; and a pressure gauge configured to measure the differential pressure between (i) a first position located in the first path and (ii) a second position located in the second path.

[0004] In some examples, the system includes a first filling volume and a second filling volume. In many such examples, the first position is within the first filling volume and the second position is within the second filling volume. In these and other examples, the first and second filling volumes may precisely coincide with each other. In these and other examples, the system may further include a fourth flow control device located in a first path and a fifth flow control device located in a second path, where the fourth and fifth flow control devices precisely coincide with each other. In some such examples, the fifth flow control device may be located upstream of the ampoule in the second path.

[0005] In various examples, the second path may include a first leg and a second leg, the ampoule may be located within the second leg, and a plurality of valves may be provided in the second path to either (a) allow the ampoule to be in fluid communication with the inlet and the second filling volume such that the second stream passing through the second filling volume contains both the carrier gas and the precursor, or (b) prevent fluid communication between the ampoule and the inlet or the second filling volume such that the second stream passing through the second filling volume contains the carrier gas but not the precursor.

[0006] In some examples, the system may further include a controller configured to measure the differential pressure between a first position and a second position. In some such examples, the controller may further be configured to determine the dose of precursor to be supplied to the processing chamber based on the measured differential pressure between the first position and the second position. In these and other examples, the controller may be configured to determine the dose of precursor to be supplied to the processing chamber based on the measured differential pressure between the first position and the second position, corrected by a zero error that takes into account the difference between the first and second paths. In some such examples, the zero error may correspond to the differential pressure between the first and second filling volumes after the first and second filling volumes have been evacuated to their reference pressures and while the ampoule is not in fluid communication with the second filling volume. In these and other examples, the first path may be maintained at a first temperature and the second path at a second temperature, with the first and second temperatures being within approximately 1°C of each other. In these or other examples, the controller may be configured to cause the processing chamber to supply a target dose of precursor when a target differential pressure is reached between a first position and a second position.

[0007] In another aspect of the disclosed example, a system is provided for supplying a dose of a precursor to a processing chamber, the system comprising: an inlet configured to allow a flow of carrier gas to enter the system; a flow divider having fluid communication with the inlet and configured to divide the flow of carrier gas into a first stream and a second stream, the first stream being supplied to a first path and the second stream being supplied to a second path; a first flow control device, a second flow control device, and a third flow control device, the first and second flow control devices each located in the first path and the third flow control device located in the second path, the first stream being supplied to the first flow control device and A first flow control device, a second flow control device, and / or a third flow control device, wherein the second stream passes through a second flow control device, and at least one of the first flow control device, a second flow control device, and / or a third flow control device is a variable flow control device configured to provide a variable flow resistance; an ampoule containing a precursor, the ampoule being placed in a second path, and the precursor being accompanied by the second stream when the second stream passes through the ampoule at a sufficiently high temperature; and a pressure gauge configured to measure the differential pressure between (i) a first position located in the first path and (ii) a second position located in the second path.

[0008] In some examples, the system includes a controller configured to measure the differential pressure between a first and a second position while the carrier gas flow is at a first temperature low enough that the precursor is substantially not entrained into the second stream, to adjust the variable flow resistance of a variable flow control device so that the differential pressure between the first and second positions is zero, and to raise the temperature of the carrier gas from the first temperature to a second temperature high enough that the precursor is entrained into the second stream, and to measure the differential pressure between the first and second positions while the carrier gas flow is at the second temperature.

[0009] Another aspect of the disclosed example provides a method for determining a dose of precursor to be supplied to a processing chamber, the method comprising: dividing a flow of carrier gas into a first stream supplied to a first path and a second stream supplied to a second path; passing the second stream over an ampoule located in the second path, the ampoule containing a precursor, and the precursor being carried along with the second stream as it passes over the ampoule at a sufficiently high temperature; passing the first stream over a first packing volume located in the first path and passing the second stream over a second packing volume located in the second path; measuring the differential pressure between the first packing volume and the second packing volume; and determining a dose of precursor to be supplied to a processing chamber based on the measured differential pressure between the first packing volume and the second packing volume.

[0010] In some examples, the step of determining the dose of precursor supplied to the processing chamber may include the step of determining a corrected differential pressure between a first packing volume and a second packing volume, the corrected differential pressure corresponding to a measured differential pressure corrected by zero error, taking into account the difference between the first path and the second path.

[0011] In some examples, the method may further include the step of determining the zero error by measuring the differential pressure between the first and second filling volumes while the first and second filling volumes are evacuated to their reference pressures and while the ampoule is not in fluid communication with the second filling volume. In some such examples, the method may further include the step of determining a corrected differential pressure between the first and second filling volumes by subtracting the zero error from the measured differential pressure between the first and second filling volumes, and the dose of the precursor is determined based on the corrected differential pressure between the first and second filling volumes.

[0012] In these or other examples, the method may further include the step of giving a warning and / or stopping the operation of the processing chamber when it is detected that the zero error is greater than the threshold zero error.

[0013] In various examples, the method may further include the step of supplying a precursor of the target dose to the processing chamber when a target differential pressure between the first filling volume and the second filling volume is reached.

[0014] In these or other examples, the first stream and the second stream may be provided to a third filling volume, additional gas may be provided to the third filling volume to further dilute the precursor, and the third filling volume may be discharged to the processing chamber when a target pressure is reached within the third filling volume.

[0015] In another aspect of the disclosed example, a method is provided for determining the dose of a precursor provided to a processing chamber. The method includes dividing a flow of carrier gas into a first stream supplied to a first path and a second stream supplied to a second path; passing the first stream through a first flow control device and a second flow control device, each of the first flow control device and the second flow control device being disposed in the first path; passing the second stream through a third flow control device disposed in the second path and passing the second stream through an ampoule disposed in the second path or over the ampoule, the ampoule containing the precursor, at least one of the first flow control device, the second flow control device, and / or the third flow control device being a variable flow control device configured to provide a variable flow resistance; measuring a differential pressure between a first position disposed in the first stream and a second position disposed in the second stream while the carrier gas is at a first temperature; adjusting the variable flow resistance of the variable flow control device so that the differential pressure between the first position and the second position becomes zero; raising the temperature of the carrier gas to a second temperature high enough to entrain a portion of the precursor in the second stream; measuring a differential pressure between the first position and the second position while the carrier gas is at the second temperature; and determining the dose of the precursor based at least in part on the differential pressure measurements at the first temperature and the second temperature.

[0016] These and other aspects are described further below with reference to the drawings.

Brief Description of the Drawings

[0017] [Figure 1] FIG. 1 shows a system for providing dose control that may be used in an example where a flow-over vaporizer is used for precursor supply.

[0018] [Figure 2] FIG. 2 shows a flowchart of a method for providing dose control in an example where a flow-over vaporizer is used for precursor supply.

[0019] [Figure 3] Figure 3 shows a flowchart of a method for calculating zero-error correction, which may be used in several examples.

[0020] [Figure 4] Figure 4 is a graph showing pressure versus time, which may be used to calculate the dose of a precursor according to various examples herein. [Figure 5] Figure 5 is a graph showing pressure versus time, which may be used to calculate the dose of a precursor according to various examples herein.

[0021] [Figure 6] Figure 6 shows a system for providing dose control that can be used in various implementation forms.

[0022] [Figure 7] Figure 7 shows a flow diagram of a method in which flow-over vapor is used to provide dose control for precursor supply.

[0023] [Figure 8] Figure 8 shows examples of deposition systems that may include the dose control system shown in Figure 1, based on various examples. [Modes for carrying out the invention]

[0024] The following explanation provides numerous specific details to fully understand the presented examples. The disclosed examples may be implemented without some or all of these specific details. In other examples, well-known process operations are not described in detail to avoid unnecessarily obscuring the disclosed examples. While the disclosed examples are described with specific examples, it should be understood that this is not intended to limit the scope of the disclosed examples.

[0025] Many semiconductor processing methods involve supplying one or more precursors to a processing chamber. Such processing methods include, but are not limited to, deposition, etching, substrate processing, and conditioning methods. Specific examples of methods that can benefit from the techniques disclosed herein include, but are not limited to, atomic layer deposition, chemical vapor deposition, atomic layer etching, and epitaxy.

[0026] Some precursors are relatively easy to supply, while others present greater difficulties. For example, liquid and solid precursors often need to be vaporized before being supplied to a vapor-based processing chamber. Direct vaporization and vapor supply via appropriate piping (often referred to as a direct vapor draw technique) may be used. Such direct vaporization may be avoided due to problems associated with heating certain precursors. For example, some low vapor pressure precursors decompose when heated and / or corrode downstream processing equipment. In such cases, it is often preferable to use a flow-over vapor precursor supply system. Examples of such precursors include, but are not limited to, MoO2Cl2, MoCl5, WCl5, and HFCl4.

[0027] In a flow-over vapor system, an inert carrier gas at a sufficiently low temperature (e.g., often one or more of Ar, He, N2, etc.) is flowed over an ampoule containing the relevant precursor, which is supplied to the processing chamber. The physical flow of the inert gas entrains the vaporized molecules of the precursor and increases the vaporization rate by constantly evacuating the headspace above the ampoule to prevent recondensation.

[0028] In such flow-over vapor systems, the vaporization rate of the precursor cannot be directly measured. While the combined flow rate of the precursor and inert gas can be measured, the precursor and inert gas are indistinguishable in the combined flow, making it difficult or impossible to accurately measure the flow of the precursor, in contrast to the inert gas.

[0029] Various techniques have been used to estimate the flow of precursors in flow-over vapor supply systems. Each of these techniques has its drawbacks. For example, one technique involves bypassable differential measurement. In this technique, the pressure in the filling volume in the precursor supply piping system is compared between (1) when the filling volume is not in fluid communication with the ampoule (e.g., when the ampoule is effectively bypassed so that no precursor is present in the filling volume) and (2) when the filling volume is in fluid communication with the ampoule containing the precursor (while the ampoule is opened and made to equilibrium with the filling volume). The gradual increase in pressure between (1) and (2) is attributable to the precursor, and the dose of the precursor is estimated based on this increase. This technique is relatively simple and works when the precursor has a vapor pressure substantially larger (e.g., greater than 10 times) than the gauge error of the pressure sensor used to measure the pressure in the filling volume. However, this technique is far less reliable for precursors with relatively low vapor pressures (e.g., less than about 1.5 times the gauge error). In such cases, random gauge errors effectively invalidate the signal from the precursor, making reliable measurements impossible. For example, the pressure sensor typically operates in the Torr range, while the precursor may have a partial pressure in the mTorr range. A further drawback of this technique is that it does not truly represent the flow rate of the precursor supplied to the processing chamber, as it relates to the precursor supply rate achieved by spontaneous evaporation, rather than the precursor supply rate achieved when the inert gas flow actively sweeps the precursor out of the ampoule. Furthermore, these two pressure measurements are taken at different times rather than simultaneously, which can introduce even more errors.

[0030] Another technique used to estimate precursor flow in flow-over vapor systems involves measuring the velocity of sound. For example, the concentration of a precursor in a combined precursor-inert gas flow may be estimated using a Piezocon gas concentration sensor, available from Veeco, Plainview, New York. In this technique, an acoustic pulse propagates through the gas sample and is measured. The time required for the pulse to propagate is determined, and the velocity of sound passing through the sample is calculated. This information, along with temperature and other gas-specific physical attributes, is used to calculate the concentrations of individual gases (e.g., precursor and inert gas) in the sample. While this technique has the advantage of being a direct measurement, it exhibits a low signal-to-noise ratio when the precursor concentration is low (e.g., when the combined precursor-inert gas flow contains less than approximately 0.2% precursor). Therefore, there are many situations in which such a technique is not particularly useful.

[0031] Further techniques used to estimate precursor flows in flow-over vapor systems include Fourier transform infrared spectroscopy (FTIR). This technique involves measuring the infrared spectrum of absorption or emission of a combined flow of precursor and inert gas. FTIR spectrometers simultaneously collect high-resolution spectral data over a wide spectral range, showing how much light a sample absorbs at each wavelength. FTIR techniques can be very accurate if signature lines in the spectrum can be identified and attributed to the associated precursor. However, such techniques are very expensive. Furthermore, FTIR techniques involve signal averaging. Such signal averaging is impractical due to the relatively short timeframes / temporal resolutions involved in many precursor supply schemes (e.g., particularly in the context of atomic layer deposition, atomic layer etching, and other processing methods where the precursor supply pulse is short (e.g., less than 1 second)).

[0032] In various examples herein, a novel technique is used for measuring the dose of a precursor supplied to a processing chamber in the context of a flow-over vapor precursor supply system. Generally speaking, this technique involves splitting the carrier gas flow into a first and second stream, adding the precursor to the second stream, and measuring the differential pressure between the first and second streams. In some examples, this technique involves providing two packing volumes within the precursor supply system and measuring the differential pressure between these two packing volumes. In other cases, these packing volumes may be omitted, and the differential pressure between the first and second streams may be measured directly. Compared to the bypassable differential measurement technique described above, some examples herein use two (rather than one) packing volumes (or other measurement spots), thereby enabling simultaneous, rather than asynchronous, measurement of (a) a combined flow of precursor and inert gas, and (b) a flow of inert gas only. This simultaneous measurement represents a significant improvement over the asynchronous measurement described above.

[0033] Figure 1 shows a simplified diagram of a flow-over vapor gas supply system that may be used in various examples. A carrier gas source 101 (for example, an inert gas, typically as described above) supplies the carrier gas to the system via an inlet 101a. The carrier gas then flows into a flow divider 102, which divides the flow into two streams. The first stream enters a first path 180 (illustrated as extending upward from the flow divider 102) and functions as a reference stream as no precursor gas is added to this stream. The second stream enters a second path 181 (illustrated as extending downward from the flow divider 102) and is the stream to which the precursor gas is added. Specifically, the second stream is divided into a first leg 177 and a second leg 178, and the precursor is supplied via an ampoule 103 located in the second leg 178. The ampoule 103 is an ampoule designed for flow-over vapor applications.

[0034] Each of these first and second paths 180 and 181 may include any flow control devices, such as a first mass flow controller 104a in the first path 180 and a second mass flow controller 104b in the second path 181. Other types of flow control devices, such as limiting flow orifices, may be used instead of, or in addition to, the first and second mass flow controllers 104a and 104b. These flow control devices are not required to perform the method described herein, but they facilitate the control and achievement of such a method. If such flow control devices are used, they may be precisely matched between the first and second paths 180 and 181. In other words, the first and second mass flow controllers 104a and 104b may be precisely matched in terms of manufacturer, batch, material, material properties, shape, size, etc. Similarly, processing conditions (e.g., temperature) may also be precisely matched. If other types of flow control devices are used, they may be similarly precisely matched in terms of the same characteristics. As used herein, the term "precise match" is intended to mean that the relevant hardware parts differ by less than about 1% with respect to the relevant characteristics (e.g., dimensions, properties, etc.). In some cases, this precise match may be even more precise, with differences of less than about 0.5% or less than about 0.1%. With respect to temperature, the first path 180 and the second path 181 may be in precise match by ensuring that the paths are within about 1°C of each other, possibly within about 0.5°C of each other, or within 0.1°C of each other. Alternatively, the first path 180 and the second path 181 may be kept isothermal, minimizing or eliminating temperature changes in each path. Similarly, streams within a path may be in precise match by ensuring that the streams are within a range of about 1°C, about 0.5°C, or about 0.1°C of each other. Alternatively, the streams may be kept isothermal, minimizing or eliminating temperature changes in each stream.

[0035] In Figure 1, the second mass flow controller 104b is shown downstream of the ampoule 103, but other arrangements are possible. For example, it may be beneficial to place the second mass flow controller 104b upstream of the ampoule 103 to prevent corrosive or other harsh chemical reactions from exposing the second mass flow controller 104b.

[0036] A first filling volume 105a is provided in the first path 180, and a second filling volume 105b is provided in the second path 181. Similar to the mass flow controllers 104a and 104b, the first filling volume 105a and the second filling volume 105b may precisely match each other with respect to one or more of the characteristics described above. For example, the first filling volume 105a and the second filling volume 105b may be produced by the same manufacturer, from the same batch, using the same material, to have the same material properties, the same shape and size, and they may be maintained at the same temperature, etc.

[0037] The differential pressure gauge 106 directly measures the differential pressure between the first filling volume 105a and the second filling volume 105b. The pressure difference is due to a precursor. The differential pressure gauge 106 allows for a much more precise and accurate measurement of the pressure difference between the first filling volume 105a and the second filling volume 105b compared to measuring and comparing the individual pressures of the first and second filling volumes 105a and 105b. Similarly, the differential pressure gauge 106 allows for simultaneous measurement of the first and second streams in the first filling volume 105a and the second filling volume 105b, which is a substantial advantage over previous methods involving asynchronous measurement for a single filling volume.

[0038] After passing through the first filling volume 105a, the first path 180 can direct the first stream to the vacuum source 108 and / or the third filling volume 105c. In contrast to the first filling volume 105a and the second filling volume 105b, the third filling volume 105c has little to no advantage from precisely matching the other filling volumes. For this reason, the third filling volume 105c may be different from the first filling volume 105a and the second filling volume 105b.

[0039] After passing through the second filling volume 105b, the second path 181 can direct the second stream to the vacuum source 108 and / or the third filling volume 105c. The first and second streams may optionally merge at the third filling volume 105c. The third filling volume 105c may be supplied by an additional gas source 109. The gas source 109 may supply an inert gas or another processing gas to the third filling volume 105c. In some cases, the gas supplied by the gas source 109 may be the same type of gas as the gas supplied by the carrier gas source 101. In other cases, these two gases may be different. The gas stream introduced by the gas source 109 may be called the third gas stream or third stream. The third gas stream may also include a third mass flow controller 104c or other type of flow control device. After passing through the third filling volume 105c, the combined gas flow may be sent to the processing chamber 107 and / or vacuum source 108. The processing chamber 107 is where the substrate is processed. Valves 150, 151, 152, 153, 154, 155, 156, 157, 158, 159, 160, 161, 162, 163, and 164 may be provided to control the flow through the system as needed. In various examples, the third filling volume 105c may be discharged into the processing chamber 107 once a target pressure is reached within the third filling volume 105c.

[0040] In addition to precisely matching the first mass flow controller 104a and the second mass flow controller 104b, and precisely matching the first filling volume 105a and the second filling volume 105b, it is desirable to match the remaining portions of the first path 180 and the second path 181 in the gas supply system as closely as possible. For example, the length and diameter of the piping used between similar portions of the first path 180 and the second path 181 may be identical or substantially the same (e.g., they may differ by only about 10% or less, or about 5% or less, or about 1% or less). This matching ensures that the measurement provided by the differential pressure gauge 106 accurately represents the pressure added as a result of the precursor from the ampoule 103, rather than differences in shape or other factors between the first path 180 and the second path 181. The pressure difference between the first packing volume 105a and the second packing volume 105b, resulting from the shape (e.g., heterogeneity between the first path 180 and the second path 181) or other non-precursor-related factors, can be measured and removed from calculations, as further described below.

[0041] Figure 2 shows a flowchart illustrating a method for measuring the dose of precursor supplied to a processing chamber using the flow-over vapor precursor supply system shown in Figure 1. As used herein, "dose" of precursor is understood to mean the amount (e.g., mass of precursor) of precursor supplied to the processing chamber for processing a substrate (or for processing a group of substrates simultaneously). The dose is supplied to the processing chamber by flowing a precursor-containing stream into the chamber over a period of time. The method in Figure 2 is described in the context of Figure 1. The method begins with operation 201, in which a first filling volume 105a, a second filling volume 105b, and a third filling volume 105c are filled / evacuated to their reference pressures. This can be achieved by opening valves 160, 161, and 163 while ensuring all other valves are closed. After the filling volumes have been filled / evacuated to the reference pressures, valves 160, 161, and 163 are closed. Next, in operation 203, the first filling volume 105a and the second filling volume 105b are pressurized while the second path 181 and the second stream are in fluid communication with the ampoule 103. This can be achieved by opening valves 151, 152, 155, 156, and 157. After the first filling volume 105a and the second filling volume 105b have been pressurized, all valves can be closed.

[0042] Next, in operation 205, the differential pressure between the first filling volume 105a and the second filling volume 105b is measured using a differential pressure gauge 106, also called a pressure gauge. This differential pressure is the measured differential pressure ΔP meas This is called the second stream and is at least partially due to the presence of precursor molecules accompanying the second stream after the second stream has passed over ampoule 103. In various examples, this measurement may be corrected by subtracting a “zero error,” as will be further described later in the context of Figures 3 and 5. In these or other examples, operation 205 may further include determining the precursor dose based on the measured differential pressure. Techniques for calculating the precursor dose based on the measured differential pressure will be further described later in the context of Figures 4 and 5.

[0043] In operation 207, gas is flowed from the first and second filling volumes 105a and 105b to the third filling volume 105c. This can be achieved by opening valves 158 and 159. After the gas has flowed from the first and second filling volumes 105a and 105b to the third filling volume 105c, valves 158 and 159 can be closed. In operation 209, additional gas may be introduced into the third filling volume 105c via an additional gas source 109. This additional gas is often argon or other inert gas used to dilute the composite stream of precursor and carrier gas to a desired precursor concentration. If this dilution may increase the associated pressure measurement error, it may be preferable to perform this dilution downstream of the precursor dose measurement (e.g., downstream of the differential pressure gauge 106, as shown in the figure) so that the additional gas does not contribute to the differential pressure measurement. In other words, it may be preferable to measure the precursor dose using as little carrier gas as possible and then dilute the precursor and carrier gas stream later as needed to reduce measurement errors. Additional gas may be supplied to the third filling volume 105c by opening valve 162. Valve 162 may remain open until the third filling volume 105c reaches the target pressure. At this point, valve 162 (and all other valves) may be closed. Next, in operation 211, gas is flowed from the third filling volume 105c into the processing chamber 107. This can be achieved by opening valve 164. At this point, the gas stream contains the precursor gas from ampoule 103, the carrier gas from carrier gas source 101, and any additional gas from additional gas source 109. This gas stream flows into the processing chamber and interacts with the semiconductor substrate, for example, in a deposition or etching process.

[0044] The method described in Figure 2 may be performed at any desired frequency. In some cases, the method may be performed each time a precursor is supplied to the processing chamber. In periodic processes in which a precursor is repeatedly administered to the processing chamber, such as atomic layer deposition or atomic layer etching, the method may be performed during each cycle or once every n cycles. In some cases, the method may be performed once per substrate or once per batch of substrates (for example, a batch is defined as a collection of substrates processed in a single chamber between a first chamber cleaning and a second chamber cleaning, with processing usually taking place at different times so that the substrates are processed sequentially). In some cases, the method may be performed regularly, such as once an hour, once a day, or once a week. Many different schedules are possible.

[0045] As described above, the first path 180 and the second path 181 (and any components therein, such as the first mass flow controller 104a and the second mass flow controller 104b, and the first filling volume 105a and the second filling volume 105b) should be matched to each other as precisely as possible. This match allows the differential pressure (ΔP) measured by the differential pressure gauge to be precisely matched. meas This ensures that the differential pressure (ΔP) accurately represents the pressure rise resulting from the precursor originating from ampoule 103, rather than any difference in shape or other factors between the first path 180 and the second path 181. To compensate for differences in these paths, zero-error correction can be performed. In this technique, the differential pressure (if any) between the first path 180 and the second path 181 is measured in the absence of the precursor from ampoule 103. The measured differential pressure at this point is the "zero-error" (ΔP) zec This is called the zero error (ΔP) and represents the baseline difference between the first path 180 and the second path 181. zec ) is the measured differential pressure (ΔP meas ) is subtracted, and the corrected differential pressure (ΔP) takes into account the difference between the first path 180 and the second path 181. cor ) will be decided.

[0046] Figure 3 shows a flowchart explaining a method for measuring and correcting zero error. This method may be used in the context of Figure 2 to improve the accuracy of the differential pressure values used to calculate the dose of the precursor. In other words, the method of Figure 2 may be modified to include one or more of the steps described in Figure 3. Similar to Figure 2, the method of Figure 3 is described with respect to the system shown in Figure 1. The method of Figure 3 begins at operation 301, where the first filling volume 105a and the second filling volume 105b are injected / vented to their reference pressures. This can be achieved by opening valves 160 and 161 while other valves remain closed. After the first filling volume 105a and the second filling volume 105b reach the reference pressure, valves 160 and 161 are closed. Next, in operation 303, a differential pressure gauge 106 is used to measure the differential pressure between the first filling volume 105a and the second filling volume 105b. This differential pressure is called "zero error" and is represented by the symbol ΔP zec and is denoted by the symbol ΔP

[0047] As described above, the zero error represents the difference between the first path 180 and the second path 181, which is independent of the presence of the precursor from the ampoule 103. To account for these differences and thereby improve the accuracy of the method of Figure 2, when implementing the method of Figure 2, the zero error (ΔP meas ) can be subtracted from the measured differential pressure (ΔP zec ). Therefore, the method of Figure 3 continues at operation 305 by subtracting the zero error (ΔP meas ) from the differential pressure (ΔP zec ) measured in operation 205 of Figure 2, thereby calculating a corrected differential pressure called ΔP cor . In other words, ΔP cor = ΔP meas - ΔP zec . Next, this corrected differential pressure ΔP cor can be used to calculate the dose of the precursor provided to the processing chamber 107.

[0048] Zero-error measurement can be used to flag a system if it is operating outside the range of acceptable parameters. For example, a threshold zero-error may be selected based on expected or normal performance. If the zero-error is measured to be greater than this threshold, the controller may issue a warning indicating that the system is not functioning as expected. Alternatively, or in addition to this, the controller may shut down the device to prevent further processing of the board until the problem causing the increase in zero-error can be addressed.

[0049] Some of the operations described in Figure 3 may be performed only once. For example, operations 301 and 303 are performed only once, resulting in zero error (ΔP zec ) may be saved for future use. In other words, the corrected differential pressure (ΔP cor ) is zero error (ΔP zec Since the corrected differential pressure (ΔP) can be calculated using previously measured and stored values, cor Operations 301 and 303 do not need to be performed every time it is required to calculate the zero error. Of course, the zero error can be remeasured at any desired frequency to account for differences between the first and second streams that may occur, for example, over time or under different processing conditions.

[0050] In certain cases, the method in Figure 2 is modified to include all of the operations in Figure 3. For example, zero error (ΔP zec Operations 301 and 303 may be performed first, followed by operations 201, 203, and 205, in order to establish and measure the zero error (ΔP) between the first filling volume 105a and the second filling volume 105b in operation 205. zec Using ) as explained in operation 305, correct the differential pressure (ΔP cor This corrected differential pressure (ΔP) is calculated. cor Using the method described herein, the dose of the precursor provided by ampoule 103 is calculated. The method in Figure 2 is followed by operations 207, 209, and 211, and if necessary, the precursor is passed into processing chamber 107.

[0051] In a similar example, the method in Figure 2 is modified to include some, but not all, of the operations in Figure 3. For example, this method is performed as described in the previous example, but without performing operations 301 and 303. Instead, the corrected differential pressure (ΔP cor ) is zero error (ΔP zec It is calculated based on the previously saved value of ).

[0052] Zero error (ΔP zec ) may be measured once or multiple times, for example, when the system is otherwise idle (e.g., not actually processing a board). Zero error (ΔP zec If the differential pressure (ΔP) is measured multiple times, correct the differential pressure (ΔP cor The zero error used to calculate the zero error may be the most recently measured zero error, or the average of such measurements.

[0053] By measuring the differential pressure between the first filling volume 105a and the second filling volume 105b (whether or not it is corrected as described in Figure 3), it becomes possible to calculate the dose of precursor provided by the flow-over vapor system shown in Figure 1. Zero error correction (ΔP zec Without considering ), the measured differential pressure (ΔP meas One technique for calculating the precursor dose based on (ΔP) is described below in the context of Figure 4. Zero error correction (ΔP zec This includes taking into account the measured differential pressure (ΔP meas Another technique for calculating the precursor dose based on ) will be discussed later in the context of Figure 5.

[0054] Figure 4 shows a graph of pressure versus time. The pressure is the measured differential pressure (ΔP) between the first filling volume 105a and the second filling volume 105b, as measured by the differential pressure gauge 106. measThis refers to the differential pressure between two filled volumes. As mentioned above, since the error associated with absolute pressure measurements is relatively large compared to the small gradual pressure increase added by the precursor from ampoule 103, it is particularly beneficial to directly measure the differential pressure between these two filled volumes rather than measuring the absolute pressure in each filled volume and calculating the difference between them. By using differential pressure gauge 106, the signal-to-noise ratio of the obtained measurements is significantly reduced. This results in a significant improvement in accuracy compared to the previous dose calculation method.

[0055] As shown in Figure 4, at time (t), the measured differential pressure is ΔP meas (t) is the result. The dose of the precursor can be calculated from this measurement using standard chemistry, for example, PV = nRT, or n = PV / (RT), where P is the measured differential pressure at time t (e.g., ΔP). meas (t)) where V is the individual volume of the first filling volume 105a and the second filling volume 105b, R is the ideal gas constant, and T is the temperature. As those skilled in the art will understand, if one or more related gases exhibit non-ideal behavior, modified calculations can be used.

[0056] The technique shown in Figure 4 above provides a reasonable estimate of the dose of the precursor provided by ampoule 103, but does not take into account the zero-error correction mentioned above in relation to Figure 3. To improve the accuracy of the dose calculation, the measured differential pressure (ΔP meas Instead of ) corrected differential pressure (ΔP cor ) can be used. Figure 5 shows a graph similar to that shown in Figure 4, but with zero error (ΔP zec This further illustrates the zero error, which is measured as described in Figure 3 and treated as a constant for the calculations in Figure 5. Corrected differential pressure (ΔP cor ) can be calculated for a given time as follows: that is, ΔP cor (t) = ΔP meas (t)-ΔP zec Subsequently, the precursor dose was measured using standard chemistry as described in relation to Figure 4, to improve accuracy, and the differential pressure (ΔP) was measured. meas Instead of ) corrected differential pressure (ΔP corIt is calculated using ).

[0057] Using the techniques described in relation to Figures 4 and 5, a precursor of the target dose can be supplied to a processing chamber for processing the substrate. Those skilled in the art will understand that the target dose can be achieved by selecting an appropriate target differential pressure (e.g., a measured differential pressure or a corrected differential pressure, depending on whether zero error correction is required). Once the differential pressure reaches the target, the precursor of the target dose is entrained in the carrier gas supplied to the second stream, and the dose is then available to the substrate in the processing chamber.

[0058] Figure 6 shows another example of a simplified precursor supply system. This example is very similar to the one shown in Figure 1, except that in this case, no packing volume is required. A carrier gas source 601 (similar to carrier gas source 101 in Figure 1) supplies carrier gas to the system through inlet 601a at a first pressure P1. The carrier gas then flows into a flow divider 602, which divides this flow into a first stream and a second stream. The first stream enters the first path 680, and the second stream enters the second path 681. An ampoule 603 (similar to ampoule 103 in Figure 1) is located in the second path 681 and contains a precursor for flow-over vapor applications. A first flow control device 676 (which may be, for example, a valve or other type of variable resistance orifice) is located in the first path 680. Furthermore, a second flow control device 699a is located in the first path 680, and a third flow control device 699b is located in the second path 681. Flow control devices 699a and 699b may each be fixed orifices providing a fixed resistance. Alternatively, flow control devices 699a and / or 699b may be variable orifices capable of providing a variable resistance. In many cases, flow control devices 699a and 699b may operate as fixed orifices for the purpose of obtaining accurate baseline measurements for determining the differential pressure, as described below in relation to Figure 7. The positions of flow control devices 676, 699a, and 699b, as well as the ampoule 603, are interchangeable. Generally speaking, the structures made up of the various flow paths / orifices / ampoules shown in Figure 6 are analogous to a Wheatstone bridge in an electrical circuit. A Wheatstone bridge allows for the measurement of an unknown electrical resistance by balancing two legs of the bridge circuit, but one leg of the bridge circuit contains an element with an unknown electrical resistance. Ampoule 603 is similar to the element in the Wheatstone bridge with an unknown electrical resistance.

[0059] A differential pressure gauge 606 (similar to differential pressure gauge 106) is provided to measure the differential pressure between (i) a position 605a located in the first path 680 and (ii) a position 605b located in the second path 681. Positions 605a and 605b may be located within the piping or other hardware for the first path 680 and the second path 681, respectively. In other words, no separate filling volume is required, and the differential pressure measurement can be performed directly between the first stream in the first path 680 and the second stream in the second path 681. In various examples, the differential pressure gauge 606 includes a membrane that physically separates the first stream in the first path 680 and the second stream in the second path 681.

[0060] The first path 680 and the second path 681 merge again at position 682 to form a stream 675 at pressure P2, which may be supplied to a processing chamber, mixing vessel, or other processing hardware. Although Figure 6 omits many of the features shown in Figure 1, it is understood that the example in Figure 6 may be implemented in the system of Figure 1 (e.g., omitting the first and second filling volumes described) or in a similar system. Thus, the features of Figure 1 may be combined with the example in Figure 6 as desired in particular cases.

[0061] As explained in relation to Figure 1, the first path 680 and the second path 681 may precisely coincide with each other in order to provide substantially identical flow resistance in the two paths. Similarly, positions 605a and 605b may precisely coincide with each other with respect to the position in the first path 680 and the position in the second path 681, respectively. The first flow control device 676 may be adjusted to achieve substantially identical flow resistance in the first path 680 and the second path 681, as will be further described later. In some cases, an arbitrary empty ampoule (not shown) may be provided in the first path 680 to mimic the effect of the ampoule 603 in the second path 681.

[0062] Figure 7 shows a flow chart of a method for measuring the dose of precursor supplied to a processing chamber using the precursor supply system shown in Figure 6. For clarity, the method in Figure 7 will be described with reference to the precursor supply system in Figure 6. The method in Figure 7 begins with operation 701, in which carrier gas is supplied from carrier gas source 601 to flow divider 602 at temperature T1, and flow divider 602 divides the carrier gas flow into a first stream passing through a first path 680 and a second stream passing through a second path 681. In operation 703, the differential pressure between the first stream and the second stream is measured at temperature T1. This measurement is performed via differential pressure gauge 606, which measures the differential pressure between (i) position 605a in the first path 680 and (ii) position 605b in the second path 681. In operation 704, the first flow control device 676 may be adjusted so that the differential pressure between position 605a and position 605b is zero, or as close to zero as possible.

[0063] The temperature T1 is set low enough so that the precursor is not substantially entrained into the second stream in the second pathway 681. The ideal T1 temperature depends on the identity and volatility of the precursor, and a relatively low T1 is used for more volatile precursors to avoid entraining the precursor in the second pathway 681 during operation 703. Essentially, operation 703 is used to create a baseline that can be compared to subsequent differential pressure measurements.

[0064] In operation 705, the temperature of the carrier gas rises to T2. T2 is greater than T1 and high enough to entrain the desired amount of precursor from ampoule 603 into the second stream of the second path 681. Next, in operation 707, the differential pressure between the first stream at position 605a and the second stream at position 605b is measured again, this time at temperature T2. The amount of precursor entrained into the carrier gas can be determined using the difference between (a) the differential pressure measured in operation 707 when substantially no precursor is present in the second stream and (b) the differential pressure measured in operation 703 when the precursor is present in the second stream. For example, it can be assumed that all or substantially all of the difference in differential pressure at the two temperatures is due to the introduction of the precursor. Therefore, the degree of change in differential pressure indicates the amount of precursor supplied.

[0065] The dose control systems described in Figures 1 and 6 may be incorporated into any type of apparatus or system for processing semiconductor substrates. Dose control systems are particularly useful in apparatus / systems where precise dose control is desired in flow-over vapor systems. Such systems are especially beneficial for supplying low vapor pressure precursors, particularly those that decompose, corrode, or cause other problems when heated. The dose control systems described herein may be used in connection with deposition, etching, substrate processing, etc. Since the systems described herein can be incorporated into many different types of substrate processing apparatuses, the details of the processing apparatus (e.g., processing chamber 107 in Figure 1) are not particularly relevant. Therefore, for brevity, only a single deposition apparatus example will be described. However, it should be understood that the dose control systems described herein are applicable to many different types of substrate processing apparatuses.

[0066] Figure 8 schematically shows an example of a process station 600 that may be used to deposit material using atomic layer deposition (ALD) and / or chemical vapor deposition (CVD), both of which may be plasma-assisted. The precursor is supplied to the process station 800 using a precursor supply system 801 corresponding to the dose control system shown in Figure 1. For example, the precursor supply system 801 may include some or all of the features shown in the dose control system of Figure 1 (except for the processing chamber 107 corresponding to the process chamber body 802). For illustrative purposes, the process station 800 is shown as a standalone process station having a process chamber body 802 to maintain a low-pressure environment. However, it is understood that multiple process stations 800 may be included in a common process tool environment. Furthermore, it is understood that in some examples, one or more hardware parameters of the process station 800 and / or the precursor supply system 801 may be programmatically adjusted by one or more computer controllers, including those described in detail herein.

[0067] The process station 800 is in fluid communication with a precursor supply system 801 for supplying process gas to a distribution shower head 806. The precursor supply system 801 includes some or all of the features of the dose control system described in relation to Figure 1. Of course, one or more additional shower heads or other inlets (not shown) may be provided for supplying additional precursors or process gases. Similarly, two or more precursor supply systems 801 may be provided, for example, if two or more flowover vapor precursors are administered to the process chamber body 802. The precursor supply system 801 may also include additional features for supplying precursors, as desired. For example, the precursor supply system 801 may include various mixing vessels and / or vaporization points (not shown) for vaporizing liquid precursors. Furthermore, any of the components of the precursor supply system 801, including any of the components of the dose control system in Figure 1, may be heat-traceable or otherwise temperature-controlled.

[0068] In some examples, the precursor supply system may further include a liquid injector for vaporizing and introducing a liquid-phase precursor. For example, the liquid injector may inject pulses of the liquid precursor into the carrier gas stream upstream of the mixing vessel. Generally speaking, the precursor supply system may be modified from the dose control system shown in Figure 1 to include various additional features as needed to supply all relevant precursors and process gases to the process chamber body 802.

[0069] In some examples, a liquid flow controller or other controller may be provided to control the mass flow rate of the liquid for vaporization and supply to the process station 800. For example, the liquid flow controller (LFC) may include a thermal mass flow meter (MFM) located downstream of the LFC. The plunger valve of the LFC may be adjusted according to a feedback control signal provided by a proportional-integral-derivative (PID) controller that communicates electrically with the MFM. However, stabilizing the liquid flow using feedback control may take more than one second. This may extend the dosing time of the liquid precursor. Therefore, in some examples, the LFC may be dynamically switched between feedback control mode and direct control mode. In some examples, the LFC may be dynamically switched from feedback control mode to direct control mode by disabling the LFC's sensing tube and PID controller.

[0070] The showerhead 806 distributes process gas toward the substrate 812. In the example shown in Figure 8, the substrate 812 is positioned below the showerhead 806 and is shown resting on a base 808. It is understood that the showerhead 806 may have any suitable shape and may have any suitable number and arrangement of holes for distributing process gas toward the substrate 812.

[0071] In some examples, a small volume 807 is positioned beneath the showerhead 806. By performing the ALD and / or CVD processes on a small volume rather than the entire volume of the process station, the exposure and sweeping time of the precursor may be reduced, the time required to change process conditions (e.g., pressure, temperature, etc.) may be reduced, and the exposure of the process station's robotics to process gases, etc., may be limited. Examples of the dimensions of the small volume include, but are not limited to, volumes of 0.1 liters to 2 liters. This small volume also affects productivity throughput. While the deposition rate per cycle decreases, the cycle time also decreases simultaneously. In certain cases, the effect of the latter is dramatic enough to improve the overall throughput of the module for a given target film thickness.

[0072] In some examples, the base 808 may be raised or lowered to expose the substrate 812 to the microvolume 807 and / or to change the volume of the microvolume 807. For example, during the substrate transport stage, the base 808 may be lowered to allow the substrate 812 to be loaded onto the base 808. During the deposition process stage, the base 808 may be raised to position the substrate 812 within the microvolume 807. In some examples, the microvolume 807 may completely enclose the substrate 812 and a portion of the base 808 to form a region of high flow impedance during the deposition process.

[0073] Optionally, the base 808 may be lowered and / or raised during parts of the deposition process to modulate the process pressure, precursor concentration, etc., within the microvolume 807. In scenarios where the process chamber body 802 remains at a reference pressure during the deposition process, the microvolume 807 may be evacuated by lowering the base 808. Examples of the ratio of the microvolume to the process chamber volume include, but are not limited to, a volume ratio of 1:600 ​​to 1:10. In some examples, it is understood that the height of the base may be programmatically adjusted by an appropriate computer controller.

[0074] In an alternative scenario, the plasma density may be varied during plasma activation and / or processing cycles included in the deposition process by adjusting the height of the base 808. At the end of the deposition process stage, the base 808 may be lowered during another substrate transport stage to allow removal of the substrate 812 from the base 808.

[0075] The examples of minute volume changes described herein refer to height-adjustable pedestals, but it is understood that in some examples the position of the shower head 806 relative to the pedestal 808 may be adjusted to change the volume of the minute volume 807. Furthermore, it is understood that the vertical position of the pedestal 808 and / or the shower head 806 may be changed by any suitable mechanism within the scope of this disclosure. In some examples the pedestal 808 may include a pivot axis for rotating the orientation of the substrate 812. In some examples it is understood that one or more of these adjustment examples may be performed programmatically by one or more suitable computer controllers.

[0076] Returning to the example shown in Figure 8, the showerhead 806 and base 808 electrically communicate with the RF power supply 814 and matching network 816 for powering the plasma. In some examples, the plasma energy may be controlled by controlling one or more of the process station pressure, gas concentration, RF power supply output, RF power supply frequency, and plasma output pulse timing. For example, the RF power supply 814 and matching network 816 may operate at any suitable output to form a plasma having a desired composition of radical species. Examples of suitable outputs are included above. Similarly, the RF power supply 814 may provide an RF output of any suitable frequency. In some examples, the RF power supply 814 may be configured to control a high-frequency RF power supply and a low-frequency RF power supply independently of each other. Examples of low-frequency RF frequencies include, but are not limited to, frequencies between 50 kHz and 600 kHz. Examples of high-frequency RF frequencies include, but are not limited to, frequencies between 1.8 MHz and 2.45 GHz. It is understood that any suitable parameters may be discretely or continuously modulated to provide plasma energy for surface reactions. As a non-limiting example, the plasma output may be pulsed intermittently to reduce ion bombardment to the substrate surface compared to a continuously powered plasma.

[0077] In some examples, the plasma may be monitored in situ by one or more plasma monitors. In some scenarios, the plasma output may be monitored by one or more voltage sensors, current sensors (e.g., VI probes). In other scenarios, the plasma density and / or process gas concentration may be measured by one or more emission spectrometers (OES). In some examples, one or more plasma parameters may be programmed to adjust based on measurements from such in-situ plasma monitors. For example, OES sensors may be used in a feedback loop for programmed control of the plasma output. In some examples, it is understood that other monitors may be used to monitor the plasma and other process characteristics. Such monitors include, but are not limited to, infrared (IR) monitors, acoustic monitors, and pressure transducers.

[0078] In some examples, the plasma may be controlled via input / output control (IOC) sequence instructions. In some examples, instructions for setting the plasma conditions of a plasma process stage may be included in the corresponding plasma activation recipe stage of the deposition process recipe. In some cases, process recipe stages may be arranged sequentially so that all instructions for a deposition process stage are executed concurrently with that process stage. In some examples, instructions for setting one or more plasma parameters may be included in a recipe stage preceding a plasma process stage. For example, a first recipe stage may include instructions for setting the flow rates of the inert gas and / or precursor gas, instructions for setting the plasma generator to an output setpoint, and a time delay instruction for the first recipe stage. A second subsequent recipe stage may include instructions for enabling the plasma generator and a time delay instruction for the second recipe stage. A third recipe stage may include instructions for deactivating the plasma generator and a time delay instruction for the third recipe stage. It is understood that these recipe stages may be further subdivided and / or repeated in any suitable manner within the scope of this disclosure.

[0079] Depending on the deposition process, plasma ignition may last on the order of several seconds or more. In certain implementations, much shorter plasma ignition may be used. These are on the order of 10 milliseconds to 1 second, typically around 20 milliseconds to 80 milliseconds, with 50 milliseconds being a specific example. Such very short RF plasma ignitions require extremely rapid plasma stabilization. To achieve this, the plasma generator may be configured to allow the frequency to float while impedance matching is preset to a specific voltage. Conventionally, high-frequency plasmas are generated at an RF frequency of about 13.56 MHz. In the various examples disclosed herein, the frequency is allowed to float to a value different from this standard. By fixing the impedance matching to a specific voltage while allowing the frequency to float, the plasma can be stabilized more quickly, which can be particularly important when using very short plasma ignitions associated with certain deposition cycles.

[0080] In some examples, the base 808 may be temperature-controlled via a heater 810. Furthermore, in some examples, pressure control of the deposition process station 800 may be provided by a butterfly valve 818. As shown in the example in Figure 8, the butterfly valve 818 controls the vacuum provided by a downstream vacuum pump (not shown). However, in some examples, pressure control of the process station 800 may be adjusted by changing the flow rate of one or more gases introduced into the process station 800.

[0081] In some implementations, the controller may be part of a system that may be part of the examples described above. Such a system may include a semiconductor processing apparatus that includes one or more processing tools, one or more chambers, one or more platforms for processing, and / or specific processing components (such as a wafer pedestal, gas flow system, etc.). These systems may be integrated with electronics to control pre-processing, processing, and post-processing operations of semiconductor wafers or substrates. The electronics may be referred to as “controllers” and may control various components or sub-components of one or more systems. Depending on the processing requirements and / or the type of system, the controller may be programmed to control any of the processes disclosed herein, including supplying processing gases, measuring and calculating precursor doses, setting temperatures (e.g., heating and / or cooling), pressure settings, vacuum settings, power settings, radio frequency (RF) generator settings in some systems, RF matching circuit settings, frequency settings, flow rate settings, fluid supply settings, position settings and operation settings, tools and other transport tools, and / or loading and unloading wafers into and out of load locks connected to or interfaced to specific systems.

[0082] Broadly speaking, a controller may be defined as an electronic device having various integrated circuits, logic, memory, and / or software that receive and issue instructions, control operations, enable cleaning operations, endpoint measurement, and so on. The integrated circuits may include a chip as firmware that stores program instructions, a chip defined as a digital signal processor (DSP), an application-specific integrated circuit (ASIC), and / or one or more microprocessors, or a microcontroller that executes program instructions (e.g., software). Program instructions are communicated to the controller in the form of various individual settings (or program files) that may define operating parameters for performing a particular process on or for a semiconductor wafer, or for a system. In some examples, the operating parameters may be part of a recipe defined by a process engineer to achieve one or more processing steps during the manufacturing of one or more layers, materials, metals, oxides, silicon, silicon dioxide, surfaces, circuits, and / or dies of a wafer.

[0083] In some implementations, the controller may be integrated with the system, coupled to it, or otherwise connected to a computer networked to the system, or a combination thereof. For example, the controller may be all or part of a factory's host computer system, or a “cloud,” enabling remote access to wafer processing. The computer may, by enabling remote access to the system, monitor the current progress of manufacturing operations, examine the history of past manufacturing operations, examine trends or metrics of multiple manufacturing operations, change parameters of the current operation, set subsequent processing steps for the current operation, or start a new process. In some examples, the remote computer (e.g., a server) may provide process recipes to the system over a network which may include a local network or the internet. The remote computer may include a user interface that enables the input or programming of parameters and / or settings, which are transmitted from the system to the remote computer. In some examples, the controller receives instructions in the form of data specifying the parameters of each processing step performed during one or more operations. The parameters may be specific to the type of process being performed and the type of tool that the controller is configured to interface with or control. Therefore, as described above, the controller may be distributed, for example, by including one or more separate controllers connected to a network and operating toward a common purpose such as the processes and control described herein. An example of a distributed controller for such purposes may be one or more integrated circuits on a chamber that communicate with one or more integrated circuits located remotely (e.g., at the platform level or as part of a remote computer) that are combined to control the processes on the chamber.

[0084] Examples of systems include, but are not limited to, plasma etching chambers or modules, deposition chambers or modules, spin rinse chambers or modules, metal plating chambers or modules, cleaning chambers or modules, bevel edge etching chambers or modules, physical vapor deposition (PVD) chambers or modules, chemical vapor deposition (CVD) chambers or modules, atomic layer deposition (ALD) chambers or modules, atomic layer etching (ALE) chambers or modules, ion implantation chambers or modules, track chambers or modules, and other semiconductor processing systems related to or used in the manufacturing and / or production of semiconductor wafers.

[0085] As described above, depending on one or more process steps performed by the tool, the controller may communicate with one or more of the following: other tool circuits or modules, other tool components, cluster tools, other tool interfaces, adjacent tools, neighboring tools, tools located throughout the factory, a main computer, another controller, or tools used for material transport to load and unload wafer containers to and from tool locations and / or load ports within the semiconductor manufacturing plant.

[0086] In this specification, the term "approximately" applied to numerical values ​​is intended to refer to values ​​within ±10% of the stated value.

[0087] conclusion While the above embodiments are described in some detail for the purpose of clarifying understanding, it will be apparent that certain modifications and variations can be carried out within the scope of the appended claims. Furthermore, there are many alternative ways to implement the processes, systems, and apparatus of these embodiments. Therefore, these embodiments are considered illustrative and not restrictive, and are not limited to the details given herein.

Claims

1. A system for supplying a precursor to a processing chamber, wherein the system is An inlet configured to allow the flow of carrier gas to enter the system, A flow divider having fluid communication with the inlet and configured to divide the flow of the carrier gas into a first stream and a second stream, wherein the first stream is supplied to a first path and the second stream is supplied to a second path, A first filling volume arranged in the first path through which the first stream passes, and a second filling volume arranged in the second path through which the second stream passes, An ampoule containing the precursor and placed in the second path, wherein when the second stream passes through the ampoule at a sufficiently high temperature, the precursor is carried along with the second stream, (i) a pressure gauge configured to measure the differential pressure between a first position located in the first path and (ii) a second position located in the second path, A system that includes this.

2. The system according to claim 1, The first position is located within the first filling volume, and the second position is located within the second filling volume. A system in which the first filling volume and the second filling volume precisely match each other.

3. The system according to claim 2, The system further includes a fourth flow control device located in the first path and a fifth flow control device located in the second path. A system in which the fourth flow control device and the fifth flow control device are precisely matched to one another.

4. The system according to claim 3, The fifth flow control device is located upstream of the ampoule in the second path of the system.

5. The system according to claim 2, The second path includes a first leg and a second leg, and the ampoule is placed within the second leg. A system comprising a plurality of valves in the second path, which either (a) allow the ampoule to be in fluid communication with the inlet and the second filling volume such that the second stream passing through the second filling volume contains both the carrier gas and the precursor, or (b) prevent fluid communication between the ampoule and the inlet or the second filling volume such that the second stream passing through the second filling volume contains the carrier gas but does not contain the precursor.

6. The system according to claim 1, A system further comprising a controller configured to measure the differential pressure between the first position and the second position.

7. The system according to claim 6, The controller is further configured to cause the system to determine the dose of precursor supplied to the processing chamber based on the measured differential pressure between the first position and the second position.

8. The system according to claim 7, The controller is configured to determine the dose of precursor supplied to the processing chamber based on the measured differential pressure between the first and second positions, corrected by zero error, taking into account the difference between the first and second paths.

9. The system according to claim 8, The zero error corresponds to the differential pressure between the first and second filling volumes after the first and second filling volumes have been evacuated to their reference pressures and while the ampoule is not in fluid communication with the second filling volume.

10. The system according to claim 9, A system in which the first path is maintained at a first temperature, the second path is maintained at a second temperature, and the first and second temperatures are within approximately 1°C of each other.

11. The system according to claim 6, The controller is configured to supply a target dose of precursor to the processing chamber when it reaches a target differential pressure between the first position and the second position.

12. A system for supplying a precursor to a processing chamber, wherein the system is An inlet configured to allow the flow of carrier gas to enter the system, A flow divider having fluid communication with the inlet and configured to divide the flow of the carrier gas into a first stream and a second stream, wherein the first stream is supplied to a first path and the second stream is supplied to a second path, A first flow control device, a second flow control device, and a third flow control device, wherein the first flow control device and the second flow control device are each arranged in the first path, the third flow control device is arranged in the second path, the first stream passes through the first flow control device and the second flow control device, the second stream passes through the third flow control device, and at least one of the first flow control device, the second flow control device, and / or the third flow control device is a variable flow control device configured to provide a variable flow resistance, An ampoule containing the precursor and placed in the second path, wherein when the second stream passes through the ampoule at a sufficiently high temperature, the precursor is carried along with the second stream. (i) a pressure gauge configured to measure the differential pressure between a first position located in the first path and (ii) a second position located in the second path, A system that includes this.

13. The system according to claim 12, The differential pressure between the first and second positions is measured while the flow of the carrier gas is at a first temperature low enough that the precursor is not substantially entrained in the second stream. The variable flow resistance of the variable flow control device is adjusted so that the differential pressure between the first position and the second position is zero. The temperature of the carrier gas is raised from the first temperature to a second temperature that is sufficiently high so that the precursor is entrained in the second stream. While the flow of the carrier gas is at the second temperature, the differential pressure between the first position and the second position is measured. The system further includes a controller configured to measure the differential pressure between the first position and the second position.

14. A method for determining the dose of a precursor supplied to a processing chamber, wherein the method is A process of dividing the carrier gas flow into a first stream supplied to a first path and a second stream supplied to a second path, A step of passing the second stream over an ampoule arranged in the second path, wherein the ampoule contains the precursor, and when the second stream passes over the ampoule at a sufficiently high temperature, the precursor is carried along with the second stream. The process of passing the first stream through a first filling volume arranged in the first path, and passing the second stream through a second filling volume arranged in the second path, A step of measuring the differential pressure between the first filling volume and the second filling volume, A step of determining the dose of precursor to be supplied to the processing chamber based on the measured differential pressure between the first filling volume and the second filling volume, A method that includes this.

15. The method according to claim 14, A method comprising the step of determining the dose of precursor supplied to the processing chamber, the step of determining a corrected differential pressure between the first filling volume and the second filling volume, wherein the corrected differential pressure corresponds to the measured differential pressure corrected by zero error, taking into account the difference between the first path and the second path.

16. The method according to claim 14, A method further comprising the step of determining zero error by measuring the differential pressure between the first and second filling volumes while the first and second filling volumes are being evacuated to their reference pressures and while the ampoule is not in fluid communication with the second filling volume.

17. The method according to claim 16, The process further includes determining a corrected differential pressure between the first and second filling volumes by subtracting the zero error from the measured differential pressure between the first and second filling volumes. A method in which the dose of the precursor is determined based on the corrected differential pressure between the first filling volume and the second filling volume.

18. The method according to claim 16, A method further comprising the steps of issuing a warning and / or stopping the operation of the processing chamber when it is detected that the zero error is greater than a threshold zero error.

19. The method according to claim 14, A method further comprising the step of supplying a target dose of precursor to the processing chamber when a target differential pressure is reached between the first filling volume and the second filling volume.

20. The method according to claim 14, The first stream and the second stream are supplied to the third filling volume. To further dilute the precursor, an additional gas is supplied to the third packing volume. A method wherein the third filling volume is discharged into the processing chamber when a target pressure is reached within the third filling volume.

21. A method for determining the dose of a precursor supplied to a processing chamber, wherein the method is A process of dividing the carrier gas flow into a first stream supplied to a first path and a second stream supplied to a second path, A step of passing the first stream through a first flow control device and a second flow control device, wherein the first flow control device and the second flow control device are each located in the first path, A step of passing the second stream through a third flow control device arranged in the second path, passing the second stream through an ampoule arranged in the second path, or passing it over an ampoule, wherein the ampoule contains the precursor, and at least one of the first flow control device, the second flow control device, and / or the third flow control device is a variable flow control device configured to provide a variable flow resistance, The process involves measuring the differential pressure between a first position located in the first stream and a second position located in the second stream while the carrier gas is at a first temperature. A step of adjusting the variable flow resistance of the variable flow control device so that the differential pressure between the first position and the second position becomes zero, A step of raising the temperature of the carrier gas to a second temperature that is sufficiently high to enclose a portion of the precursor in the second stream, The steps include measuring the differential pressure between the first position and the second position while the carrier gas is at the second temperature, A step of determining the dose of the precursor based at least partially on the differential pressure measurements at the first and second temperatures, A method that includes this.

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