Dynamic Precursor Dosing for Atomic Layer Deposition

Abstract

The present invention relates to dynamic precursor dosing for atomic layer deposition. Methods and apparatus for controlling precursor flow within a semiconductor processing tool are disclosed. A method may include: flowing a gas through a gas line; before a dosing step, opening one or more ampoule valves to cause a precursor flow to begin flowing from the ampoule through the gas line to a process chamber; closing the one or more ampoule valves to stop the precursor from flowing out of the ampoule; at the beginning of the dosing step, opening a process chamber valve to allow the precursor flow to enter the process chamber; and at the end of the dosing step, closing the process chamber valve to stop the precursor flow from entering the process chamber. A controller may include at least one memory and at least one processor, and the at least one memory may store instructions for controlling at least one processor to control the precursor flow within the semiconductor processing tool.

Description

[0001] This application is a divisional application of the invention patent application with application number 201610865153.1, application date September 29, 2016, applicant is Rum Research Company, and invention name is "Dynamic Precursor Dosing for Atomic Layer Deposition". Technical Field

[0002] The present invention relates to the field of semiconductor processing, and in particular to dynamic precursor dosing for atomic layer deposition. Background Art

[0003] Certain semiconductor manufacturing processes create films on semiconductor wafers by flowing precursors onto the wafer and then activating reactions on the substrate surface, typically with a plasma and / or a second precursor. In one such process, atomic layer deposition ("ALD"), one or more vaporized precursors are flowed from an ampoule onto the semiconductor wafer as part of one or more "dose" steps during an ALD cycle. In some conventional semiconductor processing tools, some ways of delivering precursors to a process chamber result in precursor waste. Summary of the invention

[0004] The systems, methods, and devices of the present disclosure each have several innovative aspects, no single aspect of which is entirely responsible for the desirable properties disclosed herein. These aspects include at least the following implementations, but further implementations will be set forth in the detailed description or will be apparent relative to the discussion provided herein.

[0005] In some implementations, a method for controlling a precursor flow within a semiconductor processing tool is provided. The method may include: (a) passing a gas flow through a gas line; (b) before a dosing step, opening one or more valves of an ampoule to start a precursor flow from the ampoule through the gas line to a process chamber; (c) closing one or more valves of the ampoule to stop the precursor from flowing out of the ampoule; (d) at the beginning of the dosing step, opening a process chamber valve to enable the precursor flow to enter the process chamber; and (e) at the end of the dosing step, closing the process chamber valve to stop the precursor flow from entering the process chamber.

[0006] In some further implementations, opening the one or more valves of the ampoule in (b) can occur before the dosing step for an amount of time substantially equal to a line fill time, wherein the line fill time is the time required for the precursor to flow from the ampoule to the processing chamber.

[0007] In some further implementations, closing one or more valves of the ampoule in (c) can occur before closing the process chamber valve in (e) by an amount of time substantially equal to a line fill time, wherein the line fill time is the time required for the precursor to flow from the ampoule to the process chamber.

[0008] In some further implementations, opening the process chamber valve in (d) can occur an amount of time after opening the valve of the ampoule in (b) that can be substantially equal to a line fill time, wherein the line fill time is the time required for the precursor to flow from the ampoule to the process chamber.

[0009] In some further implementations, closing the process chamber valve in (e) can occur an amount of time after closing one or more valves of the ampoule in (c) that can be substantially equal to a line fill time, wherein the line fill time is the time required for the precursor to flow from the ampoule to the process chamber.

[0010] In some further implementations, closing the one or more flow valves of the ampoule in (c) can occur an amount of time after opening the flow valves of the ampoule in (b) that can be substantially equal to the adsorption time.

[0011] In some further implementations, closing the process chamber valve in (e) can occur an amount of time after opening the process chamber valve in (d) that can be substantially equal to the adsorption time.

[0012] In some such implementations, opening one or more valves of the ampoule in (b) may occur an amount of time that may be substantially equal to a line fill time before the dosing step begins, wherein the line fill time is the time required for the precursor to flow from the ampoule to the processing chamber; closing one or more flow valves of the ampoule in (c) may occur an amount of time that may be substantially equal to an adsorption time after the flow valve of the ampoule is opened in (b); opening the processing chamber valve in (d) may occur an amount of time that may be substantially equal to the line fill time after the valve of the ampoule is opened in (b); and closing the processing chamber valve in (e) may occur an amount of time that may be substantially equal to the adsorption time after the processing chamber valve is opened in (d).

[0013] In some further such implementations, the adsorption time may be: a time less than the line fill time, a time greater than the line fill time, or a time equal to the line fill time.

[0014] In some further implementations, the one or more valves of the ampoule may be opened before the dosing step to allow the precursor to reach the process chamber when the dosing step begins.

[0015] In some further implementations, the one or more valves of the ampoule can be opened prior to the dosing step, such that the precursor at least partially fills the gas line when the dosing step begins.

[0016] In some further implementations, the one or more valves of the ampoule can be closed before the end of the dosing step, such that substantially no precursor remains in the gas line at the end of the dosing step.

[0017] In some further implementations, the one or more valves of the ampoule can be closed after a certain amount of precursor is in the gas line to achieve a desired adsorption on the wafer.

[0018] In some further implementations, the valve of the process chamber can be closed after the desired adsorption on the wafer has occurred.

[0019] In some further implementations, the valve of the process chamber valve can be closed when substantially no precursor remains in the gas line.

[0020] In some further implementations, the method further includes determining a line fill time, wherein the line fill time is a time required for a precursor to flow from the ampoule to the process chamber.

[0021] In some embodiments, a controller for a semiconductor processing tool including a precursor delivery system may be provided. The controller may include: at least one memory; and at least one processor that may be communicatively connected to the at least one memory and configured to be communicatively connected to the semiconductor processing tool and the precursor delivery system. The at least one memory may store computer executable instructions for controlling the at least one processor to: cause a gas flow through a gas line; before a dosing step, open one or more valves of an ampoule to cause a precursor flow to begin flowing from the ampoule through the gas line to a process chamber; close one or more valves of the ampoule to stop the precursor from flowing out of the ampoule; at the beginning of the dosing step, open a process chamber valve to allow the precursor flow to enter the process chamber; and at the end of the dosing step, close the process chamber valve to stop the precursor flow from entering the process chamber.

[0022] In some embodiments, the memory may further store computer executable instructions for controlling the at least one processor to open the one or more valves of the ampoule before the dosing step to allow the precursor to reach the processing chamber when the dosing step begins.

[0023] In some embodiments, the memory may also store computer executable instructions for controlling the at least one processor to close the one or more valves of the ampoule prior to the dosing step so that substantially no precursor remains in the gas line at the end of the dosing step.

[0024] In some embodiments, the memory may also store computer executable instructions for controlling the at least one processor to close the one or more valves of the ampoule after a certain amount of precursor is in the gas line to achieve desired adsorption on the wafer.

[0025] Specifically, some aspects of the present invention can be described as follows:

[0026] 1. A method for controlling precursor flow within a semiconductor processing tool, the method comprising:

[0027] (a) flowing a gas through a gas line;

[0028] (b) before the dosing step, opening one or more valves of the ampoule to initiate a flow of precursor from the ampoule through the gas line to the process chamber;

[0029] (c) closing one or more valves of the ampoule to stop the precursor from flowing out of the ampoule;

[0030] (d) opening a process chamber valve at the start of the dosing step to allow the precursor flow to enter the process chamber; and

[0031] (e) at the end of the dosing step, closing the process chamber valve to stop the flow of the precursor into the process chamber.

[0032] 2. A method according to claim 1, wherein opening one or more valves of the ampoule in (b) occurs before the dosing step for an amount of time substantially equal to a line fill time, wherein the line fill time is the time required for the precursor to flow from the ampoule to the processing chamber.

[0033] 3. A method according to claim 1, wherein closing the one or more valves of the ampoule in (c) occurs before the closing of the process chamber valve in (e) an amount of time substantially equal to the line fill time, wherein the line fill time is the time required for the precursor to flow from the ampoule to the process chamber.

[0034] 4. A method according to claim 1, wherein opening the process chamber valve in (d) occurs an amount of time after opening the valve of the ampoule in (b) that is substantially equal to a line fill time, wherein the line fill time is the time required for the precursor to flow from the ampoule to the process chamber.

[0035] 5. A method according to claim 1, wherein closing the process chamber valve in (e) occurs an amount of time substantially equal to a line fill time after closing the one or more valves of the ampoule in (c), wherein the line fill time is the time required for the precursor to flow from the ampoule to the process chamber.

[0036] 6. The method of any one of clauses 1, 2, 4 and 5, wherein closing the one or more flow valves of the ampoule in (c) occurs an amount of time substantially equal to the adsorption time after opening the flow valves of the ampoule in (b).

[0037] 7. The method of any of clauses 1-4, wherein closing the process chamber valve in (e) occurs an amount of time substantially equal to the adsorption time after opening the process chamber valve in (d).

[0038] 8. The method according to clause 1, wherein:

[0039] opening the one or more valves of the ampoule in (b) occurs an amount of time substantially equal to a line fill time before the dosing step begins, wherein the line fill time is the time required for precursor to flow from the ampoule to the process chamber;

[0040] Closing the one or more flow valves of the ampoule in (c) occurs an amount of time substantially equal to the adsorption time after opening the flow valves of the ampoule in (b);

[0041] opening the process chamber valve in (d) occurs an amount of time substantially equal to the line fill time after opening the valve of the ampoule in (b); and

[0042] Closing the process chamber valve in (e) occurs an amount of time substantially equal to the adsorption time after opening the process chamber valve in (d).

[0043] 9. The method of clause 8, wherein the adsorption time is selected from the group consisting of: a time less than the line fill time, a time greater than the line fill time, and a time equal to the line fill time.

[0044] 10. The method according to any one of clauses 1, 3, 4 and 5, wherein the one or more valves of the ampoule are opened before the dosing step to allow the precursor to reach the process chamber at the beginning of the dosing step.

[0045] 11. The method according to any one of clauses 1, 3, 4 and 5, wherein the one or more valves of the ampoule are opened before the dosing step to allow the precursor to at least partially fill the gas line at the beginning of the dosing step.

[0046] 12. The method according to any one of clauses 1, 2, 4 and 5, wherein the one or more valves of the ampoule are closed before the end of the dosing step so that substantially no precursor remains in the gas line at the end of the dosing step.

[0047] 13. The method of any one of clauses 1, 2, 4 and 5, wherein the one or more valves of the ampoule are closed after a certain amount of precursor is in the gas line to achieve a desired adsorption on the wafer.

[0048] 14. The method of any one of clauses 1 to 4, wherein the process chamber valve is closed after the desired adsorption on the wafer has occurred.

[0049] 15. The method according to any one of clauses 1 to 4, wherein the process chamber valve is closed when substantially no precursor remains in the gas line.

[0050] 16. The method according to any one of clauses 1 to 5, further comprising:

[0051] A line fill time is determined, wherein the line fill time is the time required for precursor to flow from the ampoule to the process chamber.

[0052] 17. A controller for a semiconductor processing tool including a precursor delivery system, the controller comprising:

[0053] at least one memory; and

[0054] at least one processor communicatively coupled to the at least one memory and configured to communicatively couple to the semiconductor processing tool and the precursor delivery system, wherein the at least one memory stores computer executable instructions for controlling the at least one processor to:

[0055] passing a gas flow through a gas line;

[0056] Prior to the dosing step, opening one or more valves of the ampoule to initiate a flow of precursor from the ampoule through the gas line to the process chamber;

[0057] closing the one or more valves of the ampoule to stop the precursor from flowing out of the ampoule;

[0058] At the beginning of the dosing step, opening a process chamber valve to allow the precursor flow to enter the process chamber; and

[0059] At the end of the dosing step, the process chamber valve is closed to stop the flow of the precursor into the process chamber.

[0060] 18. The controller of clause 17, wherein the memory further stores computer executable instructions for controlling the at least one processor to:

[0061] The one or more valves of the ampoule are opened before the dosing step to allow the precursor to reach the process chamber at the beginning of the dosing step.

[0062] 19. A controller according to clause 17 or 18, wherein the memory further stores computer executable instructions for controlling the at least one processor to:

[0063] The one or more valves of the ampoule are closed prior to the dosing step such that substantially no precursor remains in the gas line at the end of the dosing step.

[0064] 20. A controller according to clause 17 or 18, wherein the memory further stores computer executable instructions for controlling the at least one processor to:

[0065] The one or more valves of the ampoule are closed after a certain amount of precursor is in the gas line to achieve a desired adsorption on the wafer.

[0066] 21. A precursor delivery system, the system comprising:

[0067] ampoule;

[0068] a plurality of gas lines for fluid connection with the ampoule and the processing chamber;

[0069] a plurality of valves configured to control fluid flow into and out of the ampoule and into the processing chamber through at least the plurality of gas lines; and

[0070] A controller for controlling fluid flow in the precursor delivery system, the controller comprising control logic to:

[0071] passing a gas flow through a gas line;

[0072] Prior to the dosing step, opening one or more valves of the ampoule to initiate a flow of precursor from the ampoule through the gas line to the process chamber;

[0073] closing the one or more valves of the ampoule to stop the precursor from flowing out of the ampoule;

[0074] At the beginning of the dosing step, opening a process chamber valve to allow the precursor flow to enter the process chamber; and

[0075] At the end of the dosing step, the process chamber valve is closed to stop the flow of the precursor into the process chamber. BRIEF DESCRIPTION OF THE DRAWINGS

[0076] Figure 1 A schematic diagram of an exemplary precursor delivery system is depicted.

[0077] Figure 2 Depicted Figure 1 An example of a gas line segment of an exemplary precursor delivery system in FIG.

[0078] Figure 3 Depicted is a graphical representation of an exemplary experiment that may be used to determine line fill time.

[0079] Figure 4 Depicted is a graphical representation of the operation and timing of valves for a first exemplary implementation of a precursor delivery system when adsorption time may be less than line fill time.

[0080] Figure 5 A precursor delivery system of a first exemplary implementation is depicted at the end of precursor loading.

[0081] Figure 6 A precursor delivery system of a first exemplary implementation is depicted at the beginning of a dosing step.

[0082] Figure 7 Depicted is a graphical representation of the operation and timing of valves for a second exemplary implementation of a precursor delivery system when the adsorption time may be greater than the line fill time.

[0083] Figure 8 The precursor delivery system of the second exemplary implementation is depicted at the beginning of the dosing step.

[0084] Fig. 9 The precursor delivery system of the second exemplary implementation is depicted with the ampoule valve closed.

[0085] Fig.10 Depicted is a graphical representation of the operation and timing of valves for a third exemplary implementation of a precursor delivery system when adsorption time may be equal to line fill time.

[0086] Fig.11 The precursor delivery system of the third exemplary implementation is depicted at the beginning of the dosing step.

[0087] Fig.12 The precursor delivery system of the third exemplary implementation is depicted at the end of the dosing step.

[0088] Fig.13 Some exemplary data are described that demonstrate that use of the implementations discussed herein can result in reduced use of precursors in at least some cases.

[0089] Fig.14 An exemplary controller for a semiconductor processing tool including a precursor delivery system is depicted. DETAILED DESCRIPTION

[0090] In the following description, many specific details are stated in order to provide a thorough understanding of the provided concept. The provided concept can be implemented without some or all of these specific details. In other cases, known process operations are not described in detail to avoid unnecessarily making the described concept difficult to understand. Although some concepts will be described in conjunction with specific embodiments, it should be understood that these embodiments are not intended to be limiting.

[0091] There are many concepts and implementations described and illustrated herein. Although some features, attributes and advantages of the implementations discussed herein have been described and illustrated, it should be understood that many other features, attributes and advantages of the present disclosure, as well as different and / or similar implementations, features, attributes and advantages are apparent from the description and illustration. In this way, the above-mentioned implementations are merely exemplary. They are not intended to be exhaustive, nor are they intended to limit the present disclosure to the precise forms, technologies, materials and / or configurations disclosed. Many modifications and variations are feasible according to the present disclosure. It should be understood that other implementations can be utilized, and operational changes can be made without departing from the scope of the present disclosure. In this way, the scope of the present disclosure is not limited only to the above description, because the description of the above-mentioned implementations has been provided for the purpose of illustration and description.

[0092] The present invention is neither limited to any single aspect nor to implementation, nor to any single combination and / or permutation of these aspects and / or implementations. In addition, each of the aspects of the present disclosure and / or its implementation can be used alone or in combination with one or more aspects and / or its implementation in other aspects. For simplicity, many of these permutations and combinations will no longer be discussed and / or illustrated separately herein.

[0093] Disclosed herein are methods and apparatus for improving the delivery of precursors to a processing chamber during certain semiconductor manufacturing processes that use film deposition on a semiconductor substrate or wafer, some of which may involve multiple film deposition cycles, each cycle producing a "discrete" film thickness. Atomic layer deposition ("ALD") is one such film deposition method, but any technique for putting down one or more thin film layers, including those used in a repetitive, sequential manner, and any technique that can be viewed as involving multiple deposition cycles, may be applicable to the present disclosure. Certain implementations of depositing thin films on semiconductor wafers may involve a cyclic process that may include two half reactions on the surface of the wafer. The first half reaction may include adsorption of one or more precursors on the surface of the wafer, and the second half reaction may include converting the adsorbed precursor or precursors into a film or layer.

[0094] For example, ALD is a film forming technique that is well suited for the deposition of conformal films due to the fact that a single cycle of ALD deposits only a single thin layer of material, the thickness of which is limited by the amount of one or more film precursor reactants that can be adsorbed on the substrate surface (i.e., forming an adsorption limiting layer) prior to the film forming chemical reaction itself. Multiple "ALD cycles" can then be used to build up a film of the desired thickness, and because each layer is thin and conformal, the resulting film is substantially conformal to the shape of the underlying device structure. In certain implementations, each ALD cycle includes the following steps: (1) exposing the substrate surface to a first precursor, (2) purging a reaction chamber in which the substrate is placed, (3) activating a reaction of the substrate surface, typically with a plasma and / or a second precursor, and (4) purging the reaction chamber in which the substrate is placed. The first step listed here may be referred to as a "dosing step", the second step may be referred to as a "sweeping step", the third step may be referred to as a "radio frequency (RF) step", and the fourth step may be referred to as an "RF sweeping step".

[0095] Some implementations of semiconductor processing using precursors may include hardware, and methods may be performed, to transport the precursor to a processing chamber. In certain implementations of semiconductor processing, liquid precursors may need to be evaporated, i.e., vaporized, before being transported and / or deposited on a semiconductor wafer. The liquid precursor may be contained in an ampoule and a carrier gas, which may be an inert gas (such as argon), a non-inert gas (such as oxygen), or a non-inert gas mixture (such as oxygen and argon), which may flow through the ampoule to carry the evaporated precursor to the semiconductor processing chamber. The carrier gas may be "pushed" (wherein the gas is forced through a line) or "pulled" (wherein the gas (possibly by a vacuum) is pulled through a line) through the ampoule to carry the evaporated precursor. Throughout this disclosure, the term "precursor" may be used to describe a precursor in both a liquid and a gaseous state.

[0096] Figure 1 A schematic representation of an exemplary precursor delivery system is depicted. As can be seen, the exemplary precursor delivery system 100 includes a flow controller 102 connected to a series of pipes and valves through which fluids (e.g., liquids and / or gases) can flow, an ampoule 104, a mixing assembly 126, and a processing chamber 128. In general, the direction of fluid flow can be from Figure 1 to the right of Figure 1 , such general direction is indicated by three white arrows on the left side. For example, the flow controller 102 can be considered to be placed upstream of the ampoule 104 and the mixing assembly 126. Figure 1 In , gas lines and / or conduits of the exemplary precursor delivery system 100 are depicted as lines (which may be, for example, solid, dashed, or dotted lines), and valves are depicted as "butterfly knots" (e.g., two opposing triangles); open valves are not shaded, while closed valves are shaded. Figure 1 All valves are shown in the open state.

[0097] Flow controller 102 is connected downstream of valve 106 and upstream of the rest of the system. A propulsion gas or other fluid may flow into the system and may flow through flow controller 102. In some implementations, flow controller 102 controls the flow of the propulsion gas or other fluid. Flow controller 102 is upstream of valve 108, which is upstream of valve 110, and after valve 110 there is a junction between valve 112 and valve 114. Ampoule 104 includes two valves, namely valve 114 and valve 116, which allow gas to flow into and / or out of ampoule 104. Valve 112 is a bypass valve that allows gas to bypass ampoule 104, or avoid ampoule 104, including when valves 114 and / or 116 may be closed. Between valves 116 and 112 is another connection point, after which, for example, downstream, are valves 118 and valve 120, followed by a mixing assembly 126. Downstream of the mixing assembly 126 is a third connection point between valves 122 and 124. Valve 124 flows to the foreline 130 that does not flow into the process chamber 128, while valve 122 allows flow to the process chamber 128. For purposes of this disclosure, the terms "gas line segment" and / or "gas line" may be used to describe one or more portions of an exemplary precursor delivery system that may connect the ampoule 104 to the mixing assembly 126 and may include valves 116, 118, and 120. In some embodiments, a gas line segment may also be considered to include the line between the mixing assembly 126 and the valve 122, and / or the line between the valve 122 and the process chamber 128. Figure 2 Depicted Figure 1FIG. 1 is an exemplary gas line segment of an exemplary precursor delivery system in FIG. As can be seen, the gas line segment includes a gas line from the ampoule 104 to the process chamber 128 .

[0098] For purposes of the present disclosure, the terms "ampoule valve 114 / 116" and / or "ampoule valve" may be used to describe valves 116 and 114, such that when "ampoule valve 114 / 116" is open, valves 114 and 116 are open and precursor may flow out of the ampoule and into the gas line segment, and when "ampoule valve 114 / 116" is closed, valves 116 and 114 are closed such that no precursor may flow into the gas line segment. In some configurations, when "ampoule valve 114 / 116" may be opened, valve 112 may therefore be closed; similarly, when "ampoule valve 114 / 116" may be closed, valve 112 may be opened. Similarly, valve 122 may be considered a "process chamber valve 122" because it may allow or prevent flow into process chamber 128, while valve 124 may be considered a "foreline valve 124" because it may allow or prevent flow into foreline 130. Valve 112 may be considered a "bypass valve 112" because it allows or permits fluid to flow into ampoule 104 or to bypass or circumvent ampoule 104.

[0099] Some other precursor delivery systems may have some different components and / or configurations, but the implementations discussed herein may still be applicable to such other systems. Figure 1 As depicted in , it can be part of a semiconductor processing tool and can be connected to one or more process chambers. For exemplary purposes, the precursor delivery system discussed herein includes one process chamber, but in some implementations, it can include more than one process chamber.

[0100] The precursor delivery system can be implemented in many ways to provide the precursor to the processing chamber 128. In some implementations, the precursor can be caused to flow into the precursor delivery system when, for example, a push gas (e.g., an inert gas, such as argon, or a non-inert gas, such as oxygen) is caused to flow through the open valves 108, 110, and 114 into the ampoule 104 by the flow controller 102. In this case, the valve 112 can be closed. The vaporized precursor in the ampoule 104 can be pushed out of the ampoule 104 by the push gas and into the mixing assembly 126 through the open valves 116 and 118. In some such cases, the precursor can be caused to flow through the open valve 122 into the processing chamber 128, during which the valves 112 and 124 can be closed.

[0101] The time it takes for the vaporized precursor to flow from the ampoule 104 to the process chamber 128 can be considered the "line fill time". However, the line fill time can also be considered the time it takes for the precursor to flow from the ampoule 104 to other locations that may be upstream of the process chamber 128 (e.g., at the process chamber valve 122). Gas line filling can be considered the process of loading precursor into a gas line, such that a partially filled gas line is a gas line that may contain some but not all of the precursor, while a fully filled gas line may contain substantially all of the precursor. The time it takes for a wafer to adsorb a certain amount or a certain percentage of the precursor can be considered the "adsorption time". The adsorption time can be a saturation time, a time that is shorter than the saturation time, or a time that is longer than the saturation time. The saturation time is the time required for the surface of a workpiece (e.g., a wafer or substrate) to be fully saturated with the precursor. Saturation can be considered the point at which additional precursor cannot be adsorbed onto the workpiece surface or otherwise physically and / or chemically associated with the workpiece surface.

[0102] Some current general implementations of precursor delivery will now be discussed. In one current general implementation, during one or more steps of the ALD cycle, a push gas can be continuously flowed into the ampoule 104, such as by the flow controller 102, so that the vaporized precursor flows continuously downstream of the ampoule 104, but the continuous flow of precursor is diverted away from the processing chamber 128 during steps where it is not desired that the precursor be delivered to the processing chamber 128, and the continuous flow of precursor is directed into the processing chamber 128 when the precursor is needed in the processing chamber 128, such as during a dosing step. For example, during steps where the precursor is not delivered to the processing chamber 128, such as during an RF step, the valve 122 can be closed and the valve 124 can be opened, thereby diverting the precursor to the foreline 130; conversely, when the precursor is desired in the processing chamber 128, the valve 124 can be closed and the valve 122 can be opened. However, such continuous flow of vaporized precursors has many disadvantages, including, but not limited to, the use of large amounts of precursor and / or precursor waste.

[0103] In some other current general implementations, activation of the ampoule valve may be tied to (e.g., coupled to, and / or dependent on) the start and / or stop of a step in the process. For example, the ampoule valve 114 / 116 may be opened at the start of a dosing step or an RF sweep step, and the ampoule valve 114 / 116 may be closed at the end of the dosing step. In some such implementations, precursor flow from the ampoule 104 to the processing chamber 128 may be started at the same time as the start of a processing step (e.g., an RF sweep step), and precursor flow may be stopped at the end of the dosing step. This approach has many disadvantages, including but not limited to waste of precursor and / or use of extra time (which slows wafer throughput).

[0104] For example, in some current implementations where the precursor flows from the ampoule 104 to the processing chamber 128 at the beginning of the dosing step, the total dosing step time includes at least the line filling time plus the adsorption time. In addition, after the dosing step, the precursor may remain in the gas line section between the ampoule 104 and the processing chamber 128, which may be referred to as a "slug". The slug may be diverted (i.e., "dumped") away from the processing chamber 128 to the foreline 130 because condensation may occur in the gas line section if the slug is used in a subsequent wafer processing step, which may result in undesirable wafer defects. Some of the disadvantages of this embodiment include, among others, long dosing times, which reduce throughput (i.e., processing efficiency and total processing time), as well as waste of precursor.

[0105] Another example involves precursor beginning to flow from the ampoule 104 to the processing chamber 128 at the beginning of an RF sweep step, which is prior to the dosing step. In some such cases where the RF sweep step takes less time than the line fill time, the RF sweep step may be maintained longer than necessary to allow the precursor to reach the processing chamber 128, which may adversely affect throughput, wafer uniformity, and may waste other materials used in the RF sweep step. In some other cases where the RF sweep step takes more time than the line fill time, the precursor may reach the processing chamber 128 before the RF sweep step is completed, which may require some of the precursor to be diverted away from the processing chamber 128 and discarded, thereby wasting the precursor. In addition, as discussed above, after the dosing step is completed, the precursor may remain in the gas line between the ampoule and the processing chamber 128 and may be discarded, thereby wasting additional precursor.

[0106] In such current exemplary implementations, and other current exemplary implementations not discussed herein, the precursor delivery system is not configured to optimize line fill time and dosing time while reducing precursor usage. Such systems have significant disadvantages, including, but not limited to, adversely affecting line fill time, dosing step time, throughput, and causing wafer defects.

[0107] The inventors of the present invention have developed new methods, implementations, devices and techniques to dynamically provide and efficiently utilize precursors in semiconductor processing while achieving low defect rates. In some implementations, the opening and closing of the ampoule valve 114 / 116 can be decoupled from the start and / or stop of the processing step as described above, so that the ampoule valve 114 / 116 can be opened and / or closed independently of the start and stop of the processing step. In some such implementations, the operation of the ampoule valve 114 / 116 can be independent of the ALD step in the processing chamber. In some implementations, the precursor can also flow discontinuously. As discussed in more detail below, in order to deliver the desired amount of precursor to the processing chamber at the beginning of the dosing step, the implementations and techniques of the present invention can adjust, in particular: (A) the duration of the opening of the ampoule valve 114 / 116 and / or (B) the time when the ampoule valve 114 / 116 is opened before the dosing step.

[0108] For example, using Figure 1 , the ampoule valve 114 / 116 may be opened at a specific time before the dosing step to fill or partially fill the gas line segment before the dosing step so that the precursor reaches the processing chamber 128 at the beginning of the dosing step. The time that the ampoule valve 114 / 116 may be opened before the dosing step may depend on, among other things: the hardware of the precursor delivery system and / or semiconductor processing tool; one or more process parameters such as, for example, push gas flow rate, ampoule temperature, and / or headspace pressure; gas phase line fill time; and / or desired adsorption time. The ampoule valve 114 / 116 may remain open for a specific time in order to draw (i.e., load) an appropriate and / or desired amount of precursor from the ampoule 104 for the desired amount of wafer adsorption and / or the amount of precursor required within the gas line segment.

[0109] The ampoule valve 114 / 116 may also be closed after an appropriate and / or desired amount of precursor has flowed out of the ampoule 104. In some implementations, the desired amount of precursor may be sufficient for saturation of the wafer, for less adsorption than saturation, or more than may be required for desired adsorption and / or saturation; the amount may be variable, may vary between cycles, and / or may be controlled by a user. After all or most of the precursor has flowed into the process chamber 128, the dosing step may end, e.g., the process chamber valve 122 may be closed, such that at the end of the dosing step, the desired amount of adsorption has occurred and substantially no precursor remains in the gas line segment. In some such implementations, there may be a continuous push gas flow, e.g., a flow that does not stop during the cyclic process and / or that begins before the ampoule valve 114 / 116 is opened and stops after the process chamber valve 122 is closed.

[0110] In some of the new implementations, the timing of the valves can be associated with the start and / or stop of certain deposition operations, such as the start and stop of an ALD dosing step. The time between opening the ampoule valve 114 / 116 and the start of the dosing step may be equivalent to (or based on) the gas line fill time (as discussed above, which may be the time required for the gas to flow from the ampoule 104 to the inlet of the processing chamber 128). In addition, the ampoule valve 114 / 116 may remain open for a time equivalent to (or based on) the time required to meet the process requirements for adsorbing the precursor to the workpiece surface (as discussed above, which may be the saturation time or a percentage of the saturation time).

[0111] As mentioned above, the time at which the ampoule valve 114 / 116 is opened and / or the duration that the ampoule valve 114 / 116 is opened may depend on the adsorption time and / or the line fill time.The line fill time may be determined by a number of different methods. Figure 3 Depicted is a graphical representation of an exemplary experiment that may be used to determine line fill time. Figure 3 In particular, some of the parameters, data and results of this exemplary experiment are included. As can be seen, the entire dosing step 332 is depicted with the dosing time in seconds on the x-axis and the deposition rate on the y-axis. The RF sweep step 334 is shown in FIG. Figure 3 , indicating that such a step may be performed before the dosing step 332, and the cleaning step 336 is shown in Figure 3 , indicating that such a step may be performed after the dosing step 332. In such an experiment, the deposition rate of the wafer is measured to vary the duration of the dosing step 332 in order to determine the line fill time and the adsorption time (in this case, the saturation time is measured). Figure 3 The dosing step 332 has three parts, the first part is the pipeline filling time 338 which can occur between approximately point 344 and approximately point 346, the second part is the adsorption time 340 (which can be the saturation time) which can occur between approximately point 346 and approximately point 348, and the third part is the post-saturation 342 which can occur between approximately point 348 and approximately point 350.

[0112] In passing Figure 3 Depicted and referenced Figure 1In an experiment with an exemplary precursor delivery system in FIG. 3 , immediately before the dosing step 332 begins, ampoule valves 114 / 116 are closed, valves 106, 108, 110, 112, 118, 120, and 124 are opened, and valve 122 is closed, so that no precursor flows from ampoule 104, but push gas flows through the system and bypasses ampoule 104 through valve 112. At time zero of dosing step 332, i.e., at point 344, ampoule valves 114 / 116 are opened and valve 112 is closed to begin flowing precursor from ampoule 104 to process chamber 128. As can be seen in FIG. Figure 3 As seen in FIG. 3 , the deposition rate remains at approximately zero until approximately 0.16 seconds, represented by point 346, when deposition begins, meaning that the precursor reaches the process chamber 128 and begins depositing the precursor on the wafer, resulting in a line fill time 338 of approximately 0.16 seconds. Figure 3 The second portion of the dosing phase 332 in FIG. 3 , i.e., adsorption time 340, depicts the time for the wafer to reach the desired adsorption, which here is saturation, after which no further material is adsorbed by the wafer, and occurs at about 0.3 seconds after the start of the dosing step 332 (i.e., at point 348). Thus, for this example, the saturation time is about 0.15 seconds. During the third portion of the dosing phase 332, i.e., post-saturation 342, the precursor flows into the processing chamber 128, but no further adsorption occurs.

[0113] exist Figure 3 In the example shown, the line fill time (about 0.16 seconds) is approximately the same as the adsorption (e.g., saturation) time (about 0.15 seconds). Based on these findings, the inventors have determined that, in some cases, vapor in a completely or substantially filled line (e.g., precursor within a gas line segment from approximately valve 116 to approximately processing chamber 128) can transport all or most of the precursor that may be required for the desired adsorption and / or saturation. However, in some other embodiments where different process conditions may be used, this may not be true. In addition, the inventors have determined that line filling can be started accurately to avoid or reduce precursor waste, and the precursor flow into the gas line segment, for example, from ampoule 104, can be stopped before the end of the dosing step, for example by closing ampoule valve 114 / 116, so that the gas line segment that has been filled with precursor can be used for the remaining dosing steps, and / or the precursor flow can be decoupled from the ALD step in the chamber.

[0114] In some implementations, the measurement steps described above can be performed to determine the line fill time and / or saturation / adsorption time for a cycle, step, or process. Such information can then be used, for example, to determine the timing and duration of ampoule valve opening and closing relative to a dosing step of an ALD process. In some implementations, the measurements can be taken before, during, and / or after an ALD cycle, and can be repeated throughout a cycle, step, and / or semiconductor production process.

[0115] Some exemplary implementations showing the timing of the opening and closing of the ampoule valve relative to the dosing step and the opening and closing of the process chamber valve will now be discussed. As described above, the timing of the opening and / or closing of the ampoule valve can depend on the adsorption time and / or the line fill time. Three exemplary situations are discussed involving: the adsorption time can be less than the line fill time, the adsorption time can be more than the line fill time, and the adsorption time can be substantially equal to the line fill time. In discussing these exemplary implementations, the use of Figure 1 However, these exemplary implementations are not limited to Figure 1 The precursor delivery system of the present invention can be applied to any precursor delivery system of any semiconductor processing tool. In addition, in such an exemplary implementation, the push gas can flow continuously through the system.

[0116] In a first exemplary implementation, the adsorption time may be less than the line fill time. Figure 4 Depicted is a graphical representation of the operation and timing of valves for a first exemplary implementation of a precursor delivery system when the adsorption time may be less than the line fill time. Figure 4 In the depicted graph, time is on the x-axis and moves from left to right, but without specific units, as the units vary depending on many factors, including, but not limited to, process steps, precursors, push gas, and process conditions; the y-axis contains valve operation, that is, the "opening" or "closing" of four valves, including the process chamber valve 122, the foreline valve 124, the ampoule valves 114 / 116, and the bypass valve 112. As can be seen, before any precursor is loaded into the system, that is, before the first time point 452, the process chamber valve 122 is closed, the foreline valve 124 is opened, the ampoule valves 114 / 116 are closed, and the bypass valve is opened, thereby allowing the push gas, in particular, to flow from the flow controller 102 through the bypass valve 112, not into the ampoule 104, but into the mixing assembly 126, and through the foreline 130.

[0117] exist Figure 4At approximately the first time point 452 in FIG. 4 , the ampoule valve 114 / 116 opens and the bypass valve 112 closes, thereby allowing the push gas to flow into the ampoule 104 and allowing the precursor to begin flowing into the system. In this exemplary implementation, the ampoule valve 114 / 116 can be opened before the process chamber valve 122 is opened, and it can be open for a period of time that is equal to or substantially equal to the adsorption time 460. The ampoule valve 114 / 116 can be closed at approximately the second time point 454, which can also be before the process chamber valve 122 is opened. Figure 4 In the embodiment of the present invention, the gas line segment can be loaded with precursor between approximately the first time point 452 and approximately the second time point 454, but in a similar Figure 4 In some such implementations of the illustrated implementation, the gas line segment between the ampoule 104 and the process chamber 128 may not be sufficiently filled and loaded with precursor at the end of loading at approximately the second time point 454. This may enable a desired amount of precursor to be delivered into the gas line segment and / or into the process chamber 128.

[0118] Figure 5 A precursor delivery system of a first exemplary implementation is depicted at the end of precursor loading. Figure 4 , Figure 5 The exemplary precursor delivery system 100 is shown immediately before approximately the second time point 454. Figure 5 (as well as Figure 6 , 8 , 9, 11 and 12), as indicated by the inset in the lower right corner, the solid line indicates no flow, the dotted line indicates the push gas, and the dashed line indicates the precursor. Figure 5 As can be seen in FIG. 1 , a gas line segment (e.g., from the junction between valves 114 and 116 to the junction of valves 122 and 124) contains both precursor and push gas. In this exemplary implementation, the amount of precursor that may be loaded into the gas line segment may not completely fill the gas line segment, but may be sufficient for the desired adsorption or desired processing. Figure 5 Also shown is bypass valve 112 closed, allowing propulsion gas to enter ampoule 104 , and process chamber valve 122 closed and foreline valve 124 open, allowing propulsion gas to be diverted to foreline 130 rather than enter process chamber 128 .

[0119] Refer to Figure 4, at approximately the next time point, the third time point 456, the dosing step begins. Between the end of loading at approximately the second time point 454 and the beginning of the dosing step at approximately the third time point 456, the ampoule valve 114 / 116 can be closed, the bypass valve 112 can be opened, the foreline valve 124 can be opened, and the process chamber valve 122 can be closed. In some exemplary implementations, the dosing step can begin after the start of precursor loading (e.g., the first time point 452) by an amount of time equal to or substantially equal to the amount of time of the line fill time 462. As previously described, the line fill time 462 can be considered to be the time for the precursor to travel from the ampoule 104 to the process chamber 128. This timing will cause the precursor to arrive at the process chamber 128 at approximately the third time point 456, which can be the beginning of dosing, such as the beginning of the dosing step.

[0120] At this third time point 456, the precursor delivery system may be Figure 6 See. Figure 6 Depicted is a precursor delivery system of a first exemplary implementation at the beginning of a dosing step. As can be seen, ampoule valves 114 / 116 are closed, bypass valve 112 is open, foreline valve 124 is closed, and process chamber valve 122 is open, all of which allow precursor in a gas line section to enter process chamber 128.

[0121] Return to reference Figure 4 , the chamber valve 122 may be opened for an amount of time that allows a desired amount of precursor to enter the process chamber 128. This amount of time may be equal to or approximately equal to the adsorption time 460, as shown in FIG. Figure 4 , the adsorption time 460 may be between approximately the third time point 456 and approximately the fourth time point 458. Once the process chamber valve 122 has been open for the desired amount of time (which may be the adsorption time 460), the process chamber valve 122 may be closed and the foreline valve 124 may be opened, as depicted at approximately the fourth time point 458; this fourth time point 458 may be considered the end of the dosing step. At such a time, in some embodiments, there may be little or no precursor remaining in the gas line segment.

[0122] In a second exemplary implementation, the adsorption time may be greater than the line fill time. Figure 7 Depicts a graphical representation of the operation and timing of valves for a second exemplary implementation of a precursor delivery system when the adsorption time may be greater than the line fill time. Figure 4 In the chart, Figure 7, time is on the x-axis and moves from left to right, while the y-axis contains the operation of the valves, i.e., the "opening" or "closing" of the same four valves, including the process chamber valve 122, the foreline valve 124, the ampoule valves 114 / 116, and the bypass valve 112. As can be seen, before any precursor is loaded into the system, i.e., before the first time point 752, the process chamber valve 122 is closed, the foreline valve 124 is opened, the ampoule valves 114 / 116 are closed, and the bypass valve is opened, thereby allowing the propulsion gas, in particular, to flow from the flow controller 102 through the bypass valve 112, not into the ampoule 104, but into the mixing assembly 126, and through the foreline 130.

[0123] exist Figure 7 At approximately the first time point 752 in the embodiment, the ampoule valve 114 / 116 can be opened and the bypass valve 112 can be closed, thereby allowing the push gas to flow into the ampoule 104 and allowing the precursor to begin to flow into the system. In this second exemplary implementation, the ampoule valve 114 / 116 can be opened before the process chamber valve 122 is opened, and it can be opened for a time period equal to or substantially equal to the time period of the adsorption time 760. The ampoule valve 114 / 116 can be closed at approximately the third time point 756, which can be after the process chamber valve 122 is opened at approximately the second time point 754 (which is different from the first exemplary implementation). In some such implementations, the ampoule valve 114 / 116 can remain open after the precursor arrives and enters the process chamber 128, so that the ampoule valve 114 / 116 and the chamber valve 122 are both opened together for a period of time.

[0124] exist Figure 7 At approximately the second time point 754 in the dosing step, the dosing step begins. The second time point 754 may occur after the first time point 752 has passed an amount of time that may be equal to or substantially equal to the pipeline fill time 762. Figure 7 As can be seen in FIG. 7 , a gas line segment can be completely filled with a precursor, for example, a gas line segment from approximately the ampoule 104 to approximately the process chamber 128 can contain a precursor at approximately the second time point 754. The process chamber valve 122 is also opened at or approximately the second time point 754, which can be approximately the time when the precursor reaches the process chamber valve 122.

[0125] Figure 8 The precursor delivery system of the second exemplary implementation is shown at the beginning of the dosing step. Figure 8 Depicted Figure 7 754. As can be seen, the bypass valve 112 is closed and the precursor flows from the ampoule 104 through the open process chamber valve 122 and into the process chamber 128.

[0126] Return to reference Figure 7 , between approximately the second time point 754 and approximately the third time point 756, both the process chamber valve 122 and the ampoule valve 114 / 116 are open. As described above, at the third time point 756, the ampoule valve 114 / 116 may be closed while the process chamber valve 122 may remain open, and such closing of the ampoule valve 114 / 116 may be performed after the ampoule valve 114 / 116 is opened (i.e., at approximately the first time point 752) by an amount equal to or substantially equal to the adsorption time 760. As further described in Figure 7 As can be seen in FIG. 7 , the third time point 756 may occur before the process chamber valve 122 is closed by an amount equal to or substantially equal to the line fill time 762 .

[0127] Fig. 9 The precursor delivery system of the second exemplary implementation is depicted with the ampoule valve closed. Figure 8 Depicted Figure 7 756. As can be seen, the ampoule valves 114 / 116 are closed, while the bypass valve 112 is open.

[0128] exist Figure 7 At approximately the fourth time point 758 in FIG. 7 , the process chamber valve 122 is closed and the foreline valve 124 is opened. As described above, because the ampoule valves 114 / 116 may be closed at an amount equal to or substantially equal to the line fill time 762 before the process chamber valve 122 is closed, the gas line segment may contain little or no precursor at the fourth time point 758 when the process chamber valve 122 is closed.

[0129] In a third exemplary implementation, the adsorption time may be equal to the line fill time. Fig.10 Depicts a graphical representation of the operation and timing of valves for a third exemplary implementation of a precursor delivery system when the adsorption time may be equal to the line fill time. Figure 4 and 7 , time is on the x-axis and moves from left to right, while the y-axis contains the operation of the valves, i.e., the "opening" or "closing" of the same four valves, including the process chamber valve 122, the foreline valve 124, the ampoule valves 114 / 116, and the bypass valve 112. As can be seen, before any precursor is loaded into the system, i.e., before the first time point 1052, the process chamber valve 122 is closed, the foreline valve 124 is opened, the ampoule valves 114 / 116 are closed, and the bypass valve is opened, thereby allowing the propulsion gas, in particular, to flow from the flow controller 102 through the bypass valve 112, not into the ampoule 104, but into the mixing assembly 126, and through the foreline 130.

[0130] exist Fig.10At a first time point 1052 in FIG. 1 , the ampoule valve 114 / 116 can be opened and the bypass valve 112 can be closed, thereby enabling the push gas to flow into the ampoule 104 and allowing the precursor to begin flowing into the system. In this third exemplary implementation, the ampoule valve 114 / 116 can be opened before the process chamber valve 122 is opened, and it can be opened for a time period that is equal to or substantially equal to the time period of the adsorption time 1060, and the adsorption time 1060 and the line fill time 1062 can be the same. Fig.10 This is shown with the ampoule valve 114 / 116 open for an amount of time equal to or substantially equal to the adsorption time 1060 , which is equal to or substantially equal to the line fill time 1062 .

[0131] Both events occur at or approximately the second time point 1054. As mentioned above, the ampoule valve 114 / 116 may be closed at or approximately the second time point 1054, and the chamber valve 122 may be opened at or approximately the second time point 1054. Fig.11 The precursor delivery system of a third exemplary implementation is depicted at the beginning of the dosing step. Fig.11 Depicted in Fig.10 1054. As can be seen, the bypass valve 112 is closed and the precursor flows from the ampoule 104 through the open process chamber valve 122 and into the process chamber 128.

[0132] Similar to the ampoule valves 114 / 116, the chamber valve 122 can remain open for an amount of time equal to or substantially equal to the adsorption time 1060 and the line fill time 1062, which are equal to each other. In addition, the chamber valve 122 can be closed at approximately the third time point 1056. In such an implementation, the gas line segment is fully filled before the dosing step begins at approximately the second time point 1054. Fig.12 The precursor delivery system of the third exemplary implementation is depicted at the end of the dosing step. Fig.12 Depicted in Fig.10 1056. As can be seen, bypass valve 112 is open, ampoule valves 114 / 116 are closed, process chamber valve 122 is closed, and foreline valve 124 is open, allowing push gas to flow through the system and through foreline 130. At the end of the dosing step, such as at time 1056, all or substantially all of the precursor is exhausted from the gas line segment.

[0133] In this third exemplary implementation, the first time point 1052 can be considered as the beginning of precursor loading into the system, the time point 1054 can be considered as both the end of precursor loading and the beginning of the dosing step, and the time point 1056 can be considered as the end of the dosing step.

[0134] In all such implementations, the push gas can flow continuously. This continuous flow can ensure continuous flow of precursors and continuous purging of gas lines. When the ampoule valve 114 / 116 is closed, the push gas can bypass the ampoule and pass through the bypass valve 112, so that the push gas continues to flow toward the processing chamber 128.

[0135] In some implementations, the gas line segment can exhaust substantially all of the precursor at the end of the dosing step, while in some implementations, some precursor can remain within the gas line segment.

[0136] In some implementations, the duration that the ampoule valve 114 / 116 may be opened may be more or less than the saturation time and / or the adsorption time.

[0137] As discussed above, in some implementations, the timing of the operation of the valve can use the line fill time, the adsorption time, or some other time setting. Additionally, the reference frame for the operation of the valve can be the start of a dosing step, the stop of a dosing step, any other event during a dosing step, and / or any event during an ALD cycle.

[0138] In some implementations, including the three exemplary implementations discussed above, an amount of precursor may be sent through the gas line, which amount of precursor may be more than the amount necessary for the desired adsorption amount. The additional precursor may also be sent so that it arrives before the dosing step begins, after the dosing step, and / or after the desired adsorption / saturation has been achieved. In some such embodiments, some precursor may be accumulated in the foreline before and / or after the dosing step. In some such implementations, the duration that the ampoule valve can be opened, the timing when the ampoule valve can be opened and / or closed, the duration that the chamber valve can be opened, and / or the timing when the chamber valve can be opened may be different from the duration that the ampoule valve can be opened, and / or the timing when the chamber valve can be opened as discussed above. Figures 4 to 12 However, to reduce waste, excess precursor may be limited to about 20% or less (or about 10% or less) of the amount required for adsorption / saturation.

[0139] Furthermore, in some implementations, each event (e.g., opening of the ampoule valve, closing of the chamber valve) may not occur precisely at a predetermined point in time. Additionally, the position of the precursor at each point in time may not be as precise as discussed above. In some cases, the phrase "substantially" has been used at least with respect to timing and amount, and the term may mean within ±15% of the referenced item (e.g., time or amount). For example, if the adsorption time is 0.1 seconds, the time substantially equal to the adsorption time may be between about 0.09 seconds and about 0.11 seconds.

[0140] Additionally, the timing of the valve may not be exactly equal to the line fill time and / or adsorption time. Additionally, there may be timing delays that cause system delays, such as the time it takes to open or close the valve. In some embodiments, an ALD valve may be used that may have a timing delay of 25 milliseconds. In the implementations herein, there may also be a margin of error that may also be 25 milliseconds.

[0141] In addition, the timing when the ampoule valve opens and / or the duration of its opening may not be constant for each processing cycle (such as an ALD cycle). In some implementations, a dynamic feedback loop can be created to accurately provide the same number of moles of precursor / cycle desired for each cycle, which may be less than, equal to, or greater than the adsorption amount. The amount of precursor delivered in a flow-through gas phase system as described herein may depend on several factors, including ampoule temperature, headspace pressure, and push gas flow rate. If one or more of these parameters deviate from the expected set point throughout the process during deposition (e.g., due to changes in the level of precursor in the ampoule), the amount of precursor delivered for each ampoule valve opening time will deviate accordingly. The feedback loop can be created by sensor data (e.g., measurements) from, for example, ampoule thermocouples, pressure gauges, and MFCs, and a controller. In one example, a pressure gauge (e.g., a manometer) is located at the entrance of the process chamber (e.g., through valve 122). The arrival of the precursor in the process chamber can be notified by a pressure change detected by the pressure gauge. By dynamically controlling the ampoule open / close timing based on such a feedback loop, precursor delivery can be made more robust and repeatable between cycles. Feedback loops can be made, measurements and / or adjustments made during dosing / deposition steps, between steps within a cycle, between cycles, and / or between processes.

[0142] As described above, prior to one or more processing cycles, a measurement and / or calibration step (e.g., as described above and in Figure 3 ) can be performed to determine the adsorption time and / or pipeline filling time. Such determination can be performed similarly to that described above, for example, based on sensors or monitoring equipment that can detect one or more factors that affect precursor delivery and / or processing parameters and / or experimental steps, such as discussed above. The collected information can be used to adjust or change the timing when the ampoule valve is opened and / or the duration of such opening (for example, when it is closed). This can be performed between dosing steps, during dosing steps, between cycles, or between treatments.

[0143] The methods, embodiments, and implementations discussed herein provide numerous improvements and advantages for semiconductor processing. Some important goals of semiconductor processing may include, for example, increasing wafer yield, reducing materials, including reducing precursors, waste / usage, and improving or maintaining wafer uniformity. For example, Fig.13 Depicted are some exemplary data that indicate that the use of the implementations discussed herein can result in reduced precursor usage in at least some cases. As can be seen, the results in the right column (chart labeled "Chemical Utilization") show that the precursor is reduced from 0.323 grams per wafer to 0.225 grams per wafer. The top row represents the data shown in the middle and bottom rows. The middle row, labeled "Typical Processing," shows the utilization of chemicals for a specific semiconductor process using a typical general precursor dosing sequence, while the bottom row, labeled "New Process," shows the same semiconductor process but utilizing the utilization of chemicals delivered at least in part according to the implementations discussed herein. The bottom row shows that for the same dosing time of 0.15 seconds, the ampoule valve 114 / 116 opening time is reduced from 0.3 seconds to 0.2 seconds without adversely affecting the deposition rate and uniformity of the film. The deposition rate (depR) and NU%(R / 2) (half-range non-uniformity) are improved using the new process, which may be due to the longer ampoule valve 114 / 116 closed time resulting in an improved precursor renewal rate in the ampoule 104. The shorter ampoule valve 114 / 116 open time results in reduced precursor consumption. The new process reduces precursor waste.

[0144] Some other advantages of the present invention include, but are not limited to, reduced waste of precursor; reduced defects in wafers, which can be caused by eliminating stagnant gas line volume, by having a fully purged gas line section that may result from a continuously flowing push gas, and / or by eliminating the operation of chamber valves in the presence of precursor; and / or a reduction in dosing time and / or dosing steps, thereby improving yield.

[0145] In some implementations, the controller is part of a system, which can be part of the examples described herein. The controller can include "logic", such as the opening and closing logic of an ampoule valve or multiple ampoule valves, as described above, or other control logic discussed herein. The logic can be implemented as: software (with or without associated hardware for executing software instructions), hardware designed or configured to perform certain operations, and combinations thereof. Such a system may include semiconductor processing equipment, including one or more processing tools, one or more processing chambers, one or more platforms for processing, and / or specific processing components (including but not limited to wafer bases, gas flow systems, precursor delivery systems, gas pipelines, pipes, valves, ampoules, etc.). These systems can be integrated with electronic devices (e.g., logic) for controlling their operations before, during, and after processing semiconductor wafers or substrates. The electronic device (or logic) can be referred to as a "controller", which can control various components or sub-components of one or more systems, including, but not limited to, valves that can be configured to control the flow of fluid through one or more parts of the system or multiple systems, which can include through gas pipelines, ampoules, pipes, and / or processing chambers.

[0146] Depending on the processing requirements and / or the type of system, the controller can be programmed, designed and / or configured to control any of the processes disclosed herein, including delivery of process gases, temperature settings (e.g., heating and / or cooling), pressure settings, vacuum settings, power settings, radio frequency (RF) generator settings, RF matching circuit settings, frequency settings, flow rate settings, fluid delivery settings, position and operation settings, refilling ampoules, wafer transfer in and out of tools and other transfer tools, flow of fluids (e.g., precursors or push gases) through gas lines, ampoules, mixing assemblies, and / or processing chambers, and / or load locks connected to or interfaced with a specific system.

[0147] Broadly speaking, a controller can be defined as an electronic device having various integrated circuits, logic, memory, and / or software that receive instructions, issue instructions, control operations, enable cleaning operations, enable endpoint measurements, and the like. The integrated circuit can include a chip in the form of firmware that stores program instructions, a digital signal processor (DSP), a chip defined as an application specific integrated circuit (ASIC), and / or one or more microprocessors or microcontrollers that execute program instructions (e.g., software). The program instructions can be instructions that are transmitted to the controller in various individually set forms (or program files) that define operating parameters for performing a specific process on or for a semiconductor wafer or system. In some implementations, the operating parameters can be part of a recipe defined by a process engineer for completing one or more processing steps during the preparation of one or more (kinds of) layers, materials, metals, oxides, silicon, silicon dioxide, surfaces, circuits, and / or dies of a wafer.

[0148] In some implementations, the controller may be part of or coupled to a computer that is integrated with, connected to, or connected to the system or a combination thereof through a network. For example, the controller may be in the "cloud" or all or part of a wafer fab host system that may allow remote access to wafer processing. The computer may enable remote access to the system to monitor the current progress of a manufacturing operation, check the history of past manufacturing operations, check trends or performance criteria for multiple manufacturing operations, change parameters of the current processing, set processing steps to continue the current processing or start a new process. In some instances, a remote computer (e.g., a server) may provide a process recipe to the system through a network that may include a local network or the Internet. The remote computer may include a user interface that allows input or programming of parameters and / or settings, which is then communicated to the system from the remote computer. In some instances, the controller receives instructions in the form of data that specify the parameters of each processing step to be performed during one or more operations. It should be understood that the parameters may be for the type of process to be performed and the type of tool to be connected or controlled by the controller. Thus, as described above, the controller may be distributed, for example, by including one or more discrete controllers that are networked together and work toward a common goal (e.g., the processes and controls described herein). Examples of distributed controllers for these purposes may be one or more integrated circuits within a chamber that communicate with one or more remote integrated circuits (e.g., at a platform level or as part of a remote computer) that are combined to control processes within the chamber.

[0149] Without limitation, example systems may include plasma etch chambers or modules, deposition chambers or modules, spin cleaning chambers or modules, metal plating chambers or modules, cleaning chambers or modules, chamfer edge etch 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 etch (ALE) chambers or modules, ion implantation chambers or modules, track chambers or modules, and any other semiconductor processing system that may be associated with or used in the preparation and / or manufacture of semiconductor wafers.

[0150] As described above, depending on one or more process steps to be performed by the tool, the controller can communicate with one or more other tool circuits or modules, other tool components (e.g., precursor delivery systems), combination equipment tools, other tool interfaces, adjacent tools, neighboring tools, tools located throughout the factory, a host computer, another controller, or tools used in material handling to move containers of wafers to and from tool locations and / or load ports in a semiconductor manufacturing facility.

[0151] In some implementations, the controller may have at least one memory and one or more processors, and the memory may contain instructions for performing the functions necessary to operate the implementations discussed herein. In other implementations, the controller includes a specially designed processor that may or may not operate under the control of software instructions. The controller may be configured to control one or more aspects of a precursor delivery system and / or a semiconductor processing tool that may include a semiconductor processing system. Fig.14 An exemplary controller for a semiconductor processing tool including a precursor delivery system is depicted. As can be seen, the controller 1464 includes a memory 1466 and a processor 1468, and the processor is communicatively connected to the semiconductor processing tool 1470 and the precursor delivery system 1400 (which is a part of the semiconductor processing tool 1470). As previously described, the memory 1466 can contain instructions for, among other things, controlling the precursor delivery system 1400, for example, the memory 1466 can include instructions for controlling one or more ampoule valves, ampoules, one or more process chamber valves, one or more foreline valves, and any other aspects of the precursor delivery system, including but not limited to the flow of precursors and / or push gases through the system.

[0152] As described above, in some implementations, a system for precursor delivery may include one or more of the above-described components, including but not limited to an ampoule configured to contain a precursor and be a component of a substrate processing device (e.g., a semiconductor processing tool), a flow controller, a conduit (e.g., a gas line, a valve, a flow restrictor), the conduit may fluidly connect the ampoule, the flow controller, the mixing assembly, and the processing chamber, and be configured to control the fluid flowing through such a system. A controller may also be part of the system and may be configured to control one or more aspects of the system, including but not limited to the precursor delivery system described above.

[0153] Unless otherwise expressly required in the context of the present invention, throughout the specification and embodiments, the words "include", "comprises" and similar terms are to be interpreted in an inclusive sense as opposed to an exclusive or exhaustive sense; that is, to be interpreted in the sense of "including, but not limited to". Words using the singular or plural number also generally include the plural or singular number, respectively. In addition, the words "herein", "hereafter", "above", "below" and words of similar meaning refer to this application as a whole, not to any specific part of this application. When the word "or" is used in reference to a list of two or more items, the word covers all of the following interpretations of the word: any item in the list, all items in the list, and any combination of items in the list. The term "implementation" refers to the implementation of the techniques and / or methods described herein, as well as the physical objects that concretize the structure and / or combine the techniques and methods described herein.

[0154] There are many concepts and implementations described and illustrated herein. Although some features, attributes and advantages of the implementations discussed herein have been described and illustrated, it should be understood that many other features, attributes and advantages of the present disclosure, as well as different and / or similar implementations, features, attributes and advantages are apparent relative to the description and illustration. In this way, the above-mentioned implementations are merely exemplary. They are not intended to be exhaustive, nor are they intended to limit the present disclosure to the precise form, technology, material and / or configuration disclosed. Many modifications and variations are possible according to the present disclosure. It should be understood that other implementations can be utilized and operational changes can be made without departing from the scope of the present disclosure. In this way, the scope of the present disclosure is not fully limited to the above description, because the description of the above-mentioned implementations is provided for the purpose of illustration and description.

[0155] Importantly, the present disclosure is neither limited to any single aspect nor to implementation, nor to any single combination and / or arrangement of these aspects and / or implementations. In addition, each of the aspects of the present disclosure and / or their implementations can be used alone or in combination with one or more other aspects and / or their implementations. For simplicity, many of these arrangements and combinations will not be discussed and / or described separately herein.

[0156] The pending claims do not include limitations in the form of "means plus function" or "step plus function." (See 35 USC §112(f)). It is Applicant's intent that no claim limitation be relied upon or interpreted under USC §112(f).

Claims

1. A method for controlling precursor delivery within a semiconductor processing tool, the method comprising: (a) prior to a dosing step, initiating the flow of a precursor from a precursor source to a process chamber, wherein said initiating the flow of a precursor from a precursor source to a process chamber occurs an amount of time prior to said dosing step that is substantially equal to a line fill time, wherein said line fill time is the time required for said precursor to flow from said precursor source to said process chamber; (b) stopping the flow of the precursor out of the precursor source; (c) opening a process chamber valve at the start of the dosing step to allow the precursor flow to enter the process chamber; as well as (d) at the end of the dosing step, closing the process chamber valve to stop the flow of the precursor into the process chamber. The method according to claim 1 , wherein the precursor is in liquid form. The method according to claim 1 , wherein the precursor is in a gaseous state.

4. The method of claim 1, wherein (a) further comprises flowing a gas to the process chamber that causes the precursor to move through a gas line.

5. The method according to claim 4, wherein: The gas includes one or more of the following: an inert gas or a non-inert gas.

6. The method according to claim 1, wherein: The precursors include one or more materials for depositing layers of metals, oxides, silicon and silicon dioxide.

7. A precursor delivery system comprising: Precursor source; a plurality of gas pipelines for fluid connection with the precursor source and the processing chamber; a plurality of valves configured to control fluid flow from the precursor source into the process chamber through at least the plurality of gas lines; as well as A controller for controlling fluid flow in the precursor delivery system, the controller comprising control logic to: prior to the dosing step, initiating the flow of a precursor from a precursor source to a process chamber, wherein said initiating the flow of a precursor from a precursor source to a process chamber occurs an amount of time prior to said dosing step that is substantially equal to a line fill time, wherein said line fill time is the time required for said precursor to flow from said precursor source to said process chamber; stopping the flow of the precursor out of the precursor source; At the beginning of the dosing step, opening a process chamber valve to allow the precursor flow to enter the process chamber; as well as At the end of the dosing step, the process chamber valve is closed to stop the flow of the precursor into the process chamber.

8. The precursor delivery system according to claim 7, wherein: The precursor is in a liquid state when flowing into the process chamber.

9. The precursor delivery system according to claim 7, wherein: The precursor source includes a liquid precursor.

10. The precursor delivery system according to claim 7, wherein: When the precursor flows into the process chamber, it is in a gaseous state.

11. The precursor delivery system of claim 7, further comprising a gas source fluidly connected to the plurality of gas lines, wherein: The controller also includes control logic for flowing gas from the gas source to at least one gas line and moving the precursor through the one or more gas lines into the process chamber.

12. The precursor delivery system of claim 11, wherein: The gas includes one or more of the following: an inert gas or a non-inert gas.

13. The precursor delivery system of claim 7, wherein: The precursors include one or more materials for depositing layers of metals, oxides, silicon and silicon dioxide.

14. A method for controlling precursor flow within a semiconductor processing tool, the method comprising: (a) flowing a gas through a gas line; (b) opening one or more valves of the ampoule to initiate the flow of precursor from the ampoule through the gas line into the process chamber, and then performing a process step during which the precursor will be delivered to the wafer in the process chamber, wherein the opening of the one or more valves of the ampoule occurs an amount of time prior to the process step that is substantially equal to a line fill time, wherein the line fill time is the time required for the precursor to flow from the ampoule to the process chamber; (c) closing one or more valves of the ampoule to stop the flow of precursor from the ampoule; (d) opening a process chamber valve to allow the flow of the precursor into the process chamber at the start of the process step, and during the process step, the precursor is delivered to the wafer in the process chamber; as well as (e) at the end of the process step, closing the process chamber valve to stop the flow of the precursor into the process chamber, during which the precursor was delivered to the wafer in the process chamber.

15. The method according to claim 14, wherein: The processing step includes adsorbing the precursor onto the wafer.

16. The method of claim 14, wherein the processing step comprises converting the precursor into a film or layer.

17. The method according to claim 16, characterized in that The processing step also includes using a plasma to activate a reaction of the precursor.

18. The method of claim 16, wherein: The processing step also includes flowing a second process gas into the process chamber, and The second process gas causes activation of the precursor reaction.

19. A precursor delivery system comprising: ampoule; a plurality of gas lines for fluid connection with the ampoule and the processing chamber; a plurality of valves configured to control fluid flow into and out of the ampoule and into the processing chamber through at least the plurality of gas lines; as well as A controller for controlling fluid flow in the precursor delivery system, the controller comprising control logic to: passing a gas flow through a gas line; opening one or more valves of the ampoule to initiate flow of precursor from the ampoule through the gas line into the process chamber, and then performing a process step during which the precursor will be delivered to the wafer in the process chamber, wherein opening the one or more valves of the ampoule occurs an amount of time prior to the process step that is substantially equal to a line fill time, wherein the line fill time is the time required for precursor to flow from the ampoule to the process chamber; closing one or more valves of the ampoule to stop the flow of precursor from the ampoule; At the beginning of the processing step, a process chamber valve is opened to enable the flow of the precursor to enter the process chamber, and during the processing step, the precursor is delivered to the wafer in the process chamber; as well as At the end of the process step, the process chamber valve is closed to stop the flow of the precursor into the process chamber during which the precursor was delivered to the wafer in the process chamber.

20. The precursor delivery system of claim 19, wherein: The processing step includes adsorbing the precursor onto the wafer.

21. The precursor delivery system of claim 19, wherein: The processing step includes converting the precursor into a film or layer.

22. The precursor delivery system of claim 21, further comprising a plasma generator configured to generate plasma, wherein the processing step further comprises causing the plasma generator to generate plasma to activate a reaction of the precursor.

23. The precursor delivery system of claim 21, further comprising a second process gas source, wherein: The processing step also includes flowing a second process gas to the process chamber, and The second process gas causes activation of the precursor reaction.

24. A method for controlling precursor delivery within a semiconductor processing tool, the method comprising: opening one or more valves of the ampoule to initiate flow of precursor from the ampoule through the gas line into the process chamber, and then performing a dosing step, wherein opening the one or more valves of the ampoule occurs an amount of time prior to the dosing step that is substantially equal to a first line fill time, wherein the first line fill time is the time required for precursor to flow from the ampoule to the process chamber; closing one or more valves of the ampoule to stop the flow of precursor from the ampoule; as well as Based on sensor data generated by one or more sensors, the timing of opening and / or closing one or more valves of the ampoule is adjusted for a subsequent dosing step, wherein the sensors are configured to generate sensor data related to factors related to the flow of the precursor from the ampoule to the processing chamber.

25. The method according to claim 24, wherein: Factors related to the precursor flow are one or more of ampoule temperature, headspace pressure in the ampoule, or propulsion gas flow.

26. The method according to claim 24, wherein: The one or more sensors include one or more of the following: an ampoule thermometer, a pressure gauge or a mass flow controller.

27. The method of claim 24, wherein: The one or more sensors include a pressure gauge located at an inlet of the process chamber and configured to detect a pressure change of a gas flowing into the process chamber, The sensor data includes pressure changes of a gas flowing into the process chamber, and The adjusting is based on the sensor data.

28. The method of claim 24, further comprising determining one or more of the following based on the sensor data: adsorption time or line fill time, wherein the adjusting is based on the determination.

29. A precursor delivery system comprising: ampoule; a plurality of gas lines for fluid connection with the ampoule and the processing chamber; a plurality of valves configured to control fluid flow into and out of the ampoule and into the processing chamber through at least the plurality of gas lines; one or more sensors configured to generate sensor data related to factors associated with flow of precursor from the ampoule to the process chamber; as well as A controller for controlling fluid flow in the precursor delivery system, the controller comprising control logic to: opening one or more valves of an ampoule to initiate flow of precursor from the ampoule through the gas line into the process chamber, and then performing a dosing step, wherein opening the one or more valves of the ampoule occurs an amount of time prior to the dosing step that is substantially equal to a first line fill time, wherein the first line fill time is the time required for precursor to flow from the ampoule to the process chamber; closing one or more valves of the ampoule to stop the flow of the precursor from the ampoule; as well as Based on sensor data related to factors related to the precursor flow, the timing of opening and / or closing one or more valves of the ampoule is adjusted for a subsequent dosing step.

30. The precursor delivery system of claim 29, wherein: Factors related to the precursor flow are one or more of ampoule temperature, headspace pressure in the ampoule, or propulsion gas flow.

31. The precursor delivery system of claim 29, wherein: The one or more sensors include one or more of the following: an ampoule thermometer, a pressure gauge or a mass flow controller.

32. The precursor delivery system of claim 29, wherein: The one or more sensors include a pressure gauge located at an inlet of the process chamber and configured to detect a pressure change of a gas flowing into the process chamber, The sensor data includes pressure changes of a gas flowing into the process chamber, and The adjusting is based on the sensor data.

33. The precursor delivery system of claim 29, wherein: The controller also includes control logic to determine one or more of the following based on the sensor data: adsorption time or line fill time, and wherein the adjusting is based on the determining.

34. Semiconductor processing equipment, comprising: a processing chamber configured to receive a wafer; ampoule; a plurality of gas lines for fluid connection with the ampoule and the processing chamber; a plurality of valves configured to control fluid flow into and out of the ampoule and into the processing chamber through at least the plurality of gas lines; as well as A controller comprising control logic to: (a) flowing a gas through a gas line; (b) opening one or more valves of the ampoule to initiate the flow of precursor from the ampoule through the gas line into the process chamber, and then performing a dosing step, wherein the opening of the one or more valves of the ampoule occurs before the dosing step for an amount of time substantially equal to a line fill time, wherein the line fill time is the time required for the precursor to flow from the ampoule to the process chamber; (c) closing one or more valves of the ampoule to stop the flow of precursor from the ampoule; (d) opening a process chamber valve at the beginning of the dosing step to allow the precursor flow to enter the process chamber; as well as (e) at the end of the process step, closing the process chamber valve to stop the flow of the precursor into the process chamber.

35. The semiconductor processing apparatus according to claim 34, wherein: Closing of the one or more valves of the ampoule in (c) occurs before closing of the process chamber valve in (e) a time substantially equal to the line fill time.

36. The semiconductor processing apparatus according to claim 34, wherein: Opening the process chamber valve in (d) is performed after opening the ampoule valve in (b) for an amount of time substantially equal to the line fill time.

37. The semiconductor processing apparatus according to claim 34, wherein: Closing the process chamber valve in (e) is performed after closing the one or more valves of the ampoule in (c) for an amount of time substantially equal to the line fill time.

38. The semiconductor processing apparatus according to claim 34, wherein: Closing the one or more valves of the ampoule in (c) is performed after opening the valve of the ampoule in (b) for an amount of time substantially equal to the adsorption time of the dosing step.

39. The semiconductor processing apparatus according to any one of claims 34 to 38, wherein: Closing the process chamber valve in (e) is performed after opening the process chamber valve in (d) for an amount of time substantially equal to the adsorption time of the dosing step.

40. The semiconductor processing apparatus of claim 34, wherein: before the dosing step begins, opening the one or more valves of the ampoule in (b) occurs for an amount of time substantially equal to the line fill time, Closing the one or more valves of the ampoule in (c) occurs after opening the valve of the ampoule in (b) for an amount of time substantially equal to the adsorption time of the dosing step, opening the process chamber valve in (d) is performed after opening the ampoule valve in (b) for an amount of time substantially equal to the line fill time, After the process chamber valve is opened in (d) for an amount of time substantially equal to the adsorption time, closing the process chamber valve in (e) is performed.

41. The semiconductor processing apparatus according to claim 40, wherein: The adsorption time is selected From: time less than the pipeline fill time, time greater than the pipeline fill time and A time equal to the pipeline filling time.

42. The semiconductor processing apparatus according to any one of claims 34 to 38, wherein: One or more valves of the ampoule are opened prior to the dosing step to allow the precursor to reach the process chamber at the start of the dosing step.

43. The semiconductor processing apparatus according to any one of claims 34 to 38, wherein: One or more valves of the ampoule are opened prior to the dosing step, so that the precursor at least partially fills the gas line at the beginning of the dosing step.

44. The semiconductor processing apparatus according to any one of claims 34 to 38, wherein: After the desired suction of the wafer has occurred, the valve of the process chamber is closed.

45. The semiconductor processing apparatus according to any one of claims 34 to 38, wherein: When substantially no precursor remains in the gas line, the valve of the process chamber is closed.

46. ​​The semiconductor processing apparatus according to any one of claims 34 to 38, wherein: The controller also includes control logic for causing determination of the line fill time.

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