阅读说明：本技术 气相化学反应器和其使用方法 (Gas phase chemical reactor and method of using same ) 是由 A·J·尼斯坎恩 于 2019-06-03 设计创作，主要内容包括：公开了一种气相化学反应器、包括所述反应器的系统,以及使用所述反应器和系统的方法。示范性反应器包括反应室且被配置成向反应室内提供前体历时一个浸渍期,例如其中停止向所述反应室供应所述前体且在开始吹洗反应室之前的时期。这允许在衬底处理期间在反应室内获得相对较高滞留时间、相对较高前体分压和/或相对较高绝对压力。(a gas phase chemical reactor, a system including the reactor, and methods of using the reactor and system are disclosed. An exemplary reactor includes a reaction chamber and is configured to provide a precursor into the reaction chamber for an immersion period, e.g., a period in which the supply of the precursor to the reaction chamber is stopped and before purging of the reaction chamber begins. This allows relatively high residence times, relatively high precursor partial pressures, and/or relatively high absolute pressures to be obtained within the reaction chamber during substrate processing.)

1. A gas phase chemical reactor, comprising:

A reaction chamber for processing a substrate;

A load/unload chamber comprising an opening for receiving the substrate and a valve for sealing the opening;

a susceptor having a top surface to receive the substrate, wherein the susceptor is movable within the load/unload chamber, and wherein the top surface of the susceptor defines at least a portion of a bottom section of the reaction chamber when the substrate is in a processing position;

A vacuum source for evacuating the load/unload chamber; and

A controller for controlling a precursor delivery process and an evacuation process, the controller comprising a memory programmed to enable the controller to perform the steps of:

When the susceptor is in the processing position,

Providing a precursor to the reaction chamber while evacuating the load/unload chamber with the vacuum source; and

Stopping the flow of the precursor, an

Evacuating the reaction chamber by moving the susceptor into the load/unload chamber.

2. The gas phase chemical reactor of claim 1, further comprising a protective cover to protect the valve.

3. The gas phase chemical reactor of claim 2, further comprising an inert gas source, wherein inert gas from the inert gas source is provided between an inner wall of the load/unload chamber and a surface of the protective shield.

4. The gas phase chemical reactor of claim 1, further comprising a shaft for moving the pedestal and a protective cover surrounding at least a portion of the shaft.

5. The gas phase chemical reactor of claim 4, wherein the protective cover comprises a bellows.

6. The gas phase chemical reactor of claim 1, wherein a seal is formed between the reaction chamber and the load/unload chamber during processing of the substrate.

7. The gas phase chemical reactor of claim 1, wherein a ratio of an internal volume of the load/unload chamber to an internal volume of the reaction chamber is greater than 5 to 1.

8. The gas phase chemical reactor of claim 1, wherein the step of moving the susceptor to the load/unload chamber includes exposing the substrate to a second pressure of the load/unload chamber that is lower than a first pressure within the reaction chamber.

9. The gas phase chemical reactor of claim 1, further comprising a guide to guide a gas flow from the reaction chamber to the load/unload chamber.

10. The gas phase chemical reactor of claim 2, wherein the protective shield does not contact an inner wall of the load/unload chamber when the valve is moved from an open position to a closed position.

11. The gas phase chemical reactor of claim 1, wherein the memory is programmed to enable the controller to perform the following steps after stopping the precursor flow:

Exposing the substrate to the precursor in the reaction chamber for an immersion period; and

after the immersion period, the reaction chamber is evacuated by moving the susceptor to the loading/unloading chamber.

12. A system comprising the gas phase chemical reactor of claim 1.

13. The system of claim 12, further comprising a direct plasma device.

14. the system of claim 13, further comprising a remote plasma device.

15. The system of claim 14, further comprising a showerhead gas distribution device.

16. The system of claim 12, further comprising a robotic arm to transfer the substrate from outside the gas phase chemical reactor through the opening onto the susceptor.

17. A method, comprising the steps of:

Moving the susceptor from the loading/unloading position to the processing position;

When the susceptor is in the processing position,

Supplying the precursor to the reaction chamber while evacuating the load/unload chamber; and

Stopping the flow of the precursor; and

Moving the susceptor into the load/unload chamber to expose the substrate to a second pressure lower than the first pressure.

18. The method of claim 17, further comprising opening a valve to receive the substrate, closing the valve to seal the opening, and protecting the valve with a protective cover.

19. The method of claim 17, further comprising using a carrier gas during only a portion of the step of providing a precursor.

20. The method of claim 17, further comprising the step of providing a purge gas during or after the step of moving the pedestal into the load/unload chamber.

21. the method of claim 17, further comprising exposing a substrate to the precursor within the reaction chamber at a first pressure for an immersion period; and after the soak period, moving the susceptor into the load/unload chamber to expose the substrate to a second pressure lower than the first pressure.

Technical Field

The present disclosure relates generally to gas phase apparatuses and methods. More specifically, exemplary embodiments of the invention relate to gas phase chemical reactors suitable for precursor impregnation applications, systems including such reactors, and methods of using the reactors and systems.

Background

Gas phase chemical reactors can be used for a variety of applications, such as depositing material on a surface of a substrate and/or etching material. A typical gas phase chemical reactor comprises a reaction chamber; a gate valve that opens to receive a substrate and closes during substrate processing; and one or more gas sources coupled to the reaction chamber.

During substrate processing, one or more precursors are flowed into the reaction chamber to deposit and/or react with materials on the substrate surface to etch the materials. Generally, during substrate processing, the gas flow reaches steady state and continues; that is, after a period of time, unreacted gas and any gaseous by-products are continuously removed from the reaction chamber as the gas is introduced into the reaction chamber.

as an example, during a typical Atomic Layer Deposition (ALD) process, a first precursor is provided to a reaction chamber, either in a continuous manner for a period of time or as a step, in order to remove unreacted first precursor and/or any gaseous by-products of the first precursor during said step. This facilitates the precursor flow across the substrate surface during said step. The substrate is then exposed to a reduced pressure and/or a purge gas to further remove any excess precursor and/or by-products during the purge step. When the same and/or other precursors are desired, these steps can be repeated until a film of the desired thickness is obtained.

While such techniques work relatively well in some applications, in other applications, continuously flowing one or more precursors during substrate processing can produce undesirable waste of unreacted precursors, undesirably extend substrate processing time, and/or produce films with undesirable characteristics. In addition, it can be difficult to obtain the desired concentration, partial pressure, and/or absolute reaction chamber pressure to drive some reactions using such techniques. For example, in some ALD processes (e.g., using SAM.24 (Air liquid) as a silicon precursor), the precursor may be able to quickly reach an initial growth rate saturation level, but the precursor may not reach full growth rate saturation at typical precursor partial pressures, even though the pulse time is relatively long; thus, the growth rate of the deposited film may be below a desired value₄and NH₃When depositing TiN, NH₃It is desirable to have a relatively high concentration or partial pressure to produce undesired/poisons in the formation of by-productsPrime ahead driving the film-forming reaction to completion). Such high partial pressures may be difficult to achieve with typical reactors. In addition, the formation of self-assembled monolayers may require relatively long exposure times and/or relatively high precursor concentrations/partial pressures to achieve desired film properties, and such conditions may be difficult to achieve with typical reactors. Furthermore, chemical vapor reactors typically employ relatively expensive gas distribution devices to uniformly distribute the gas over the substrate surface; such a design may be desirable when the precursor is continuously flowed across the substrate surface. Accordingly, improved vapor phase chemical processing apparatus and methods are desired.

Any discussion of the problems provided in this section is included in the disclosure merely to provide a background for the invention and should not be taken as an admission that any or all of the discussion is known at the time of completion of the invention.

Disclosure of Invention

Various embodiments of the present disclosure provide an apparatus and method capable of providing an extended residence time, partial pressure, and/or absolute pressure of one or more precursors within a reaction chamber of a gas phase chemical reactor. As set forth in more detail below, the various systems and methods allow for relatively less precursor usage and waste as compared to conventional apparatus and methods, thereby enabling a reduction in costs associated with processing substrates. The exemplary systems and methods can also facilitate high growth rates and/or drive reactions that may not otherwise occur. Additionally or alternatively, exemplary embodiments enable relatively rapid pumping/evacuation of gas from a reaction zone or chamber within a gas phase chemical reactor. Further, some exemplary systems and methods do not require the use of relatively expensive gas distribution devices to achieve the desired process uniformity.

According to at least one example embodiment of the present disclosure, a gas phase chemical reactor includes a reaction chamber for processing a substrate; a load/unload chamber including an opening to receive a substrate and a valve (e.g., a gate valve) to seal the opening; a pedestal having a top surface to receive a substrate, wherein the pedestal is movable within a load/unload chamber, and wherein the top surface of the pedestal defines at least a portion of a bottom section of the reaction chamber when a substrate is in a processing position; and a vacuum source for evacuating the load/unload chamber. The gas phase chemical reactor can further include a controller, for example, to control the precursor delivery process and the evacuation process. The controller includes a memory programmed to enable the controller to perform the steps of: providing a precursor into the reaction chamber while the susceptor is in the processing position, while evacuating the load/unload chamber; stopping the precursor flow; and evacuating the reaction chamber by moving the susceptor into the load/unload chamber. Additionally, the gas phase chemical reactor may include a protective shield (e.g., a plate) to protect the valves. The protective cover is attachable to the valve. According to various aspects of these embodiments, the protective cover extends beyond at least a top surface of the gate valve. According to a further exemplary aspect, a gas phase chemical reactor includes an inert gas source, wherein inert gas from the inert gas source is provided between an inner wall of a loading/unloading chamber and a surface of a protective cover. The gas phase chemical reactor may also include a movable shaft coupled to the susceptor. In these cases, the gas phase chemical reactor may include a protective cover (e.g., bellows) surrounding at least a portion of the movable shaft and a shaft opening located in the bottom of the load/unload chamber. As discussed in more detail below, according to various examples, the volumes of the reaction chamber and the load/unload chamber can be configured to facilitate rapid pumping of the reaction chamber. For example, the volume ratio of the reaction chamber interior volume to the load/unload chamber interior volume can be in the range of about 1:5 to about 1:160, about 1:10 to about 1:80, or about 1:20 to about 1: 60. The gas phase chemical reactor described herein may include a showerhead gas distribution arrangement. In at least some instances, the exemplary gas phase chemical reactor may not include a showerhead gas distribution or similar device, and thus may be less complex and/or less expensive than other gas phase chemical reactors. According to other aspects, the gas phase chemical reactor comprises a guide to guide the gas flow from the reaction chamber to the loading/unloading chamber, e.g. during the purging step. The guide can be further configured to mitigate contact of gas from the reaction chamber with the load/unload chamber walls. In these cases, the gas phase chemical reactor may not include a protective cover.

According to other exemplary embodiments of the present disclosure, a system includes a gas phase chemical reactor, such as those described herein, and one or more other components, such as a vacuum source, one or more precursor sources, one or more purge gas sources, one or more carrier gas sources, a transfer or robotic arm, and the like.

According to yet another exemplary embodiment of the present disclosure, a method (e.g., for processing a substrate) comprises the steps of: moving the susceptor from the loading/unloading position to the processing position; providing a precursor into the reaction chamber while the susceptor is in the processing position (e.g., by providing a vacuum or maintaining a vacuum within the load/unload chamber); stopping the precursor flow; and moving the susceptor into the loading/unloading chamber. The substrate may be exposed to a second pressure, e.g., a pressure lower than the first pressure, while the substrate is moved into the load/unload chamber. The method can further comprise the steps of: the valve is opened to receive the substrate, closed to seal the opening and/or protected with a protective cover. Additionally or alternatively, the method may comprise providing a carrier gas during all or a portion of the step of providing the precursor.

The foregoing summary and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure or the invention.

Drawings

Embodiments of the present disclosure may be more completely understood by reference to the detailed description and claims, taken in conjunction with the following illustrative drawings.

Fig. 1 illustrates a system including a gas phase chemical reactor in a loading/unloading position according to at least one embodiment of the present disclosure.

Fig. 2 illustrates a system including a gas phase chemical reactor in a processing location according to at least one embodiment of the present disclosure.

FIG. 3 illustrates a portion of a system including a gas phase chemical reactor in a purge position according to at least one embodiment of the present disclosure.

Fig. 4 illustrates a valve and a protective cover according to at least one embodiment of the present disclosure.

Fig. 5 illustrates a method according to at least one embodiment of the present disclosure.

Fig. 6 illustrates a pressure map in accordance with at least one embodiment of the present disclosure.

Fig. 7 illustrates a portion of another system including a gas phase chemical reactor according to at least one embodiment of the present disclosure.

It will be appreciated that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help improve understanding of the illustrated embodiments of the present disclosure.

Detailed Description

The description of the exemplary implementations of the methods and systems provided below is exemplary only and is for illustrative purposes only; the following description is not intended to limit the scope of the present disclosure or the claims. Furthermore, references to multiple embodiments having the described features are not intended to exclude other embodiments having other features or other embodiments incorporating different combinations of the described features.

Any range indicated in this disclosure may include or exclude the endpoints. Additionally, any variable values indicated (whether they are indicated by "about" or not) may refer to exact or approximate values and include equivalent values, and may refer to average, median, representative, multiple values, and the like.

as used herein, precursor refers to one or more gases that participate in a chemical reaction. The chemical reaction may take place in the gas phase and/or between the gas phase and the substrate surface and/or a substance on the substrate surface.

The systems, reactors, and methods described herein can be used in a variety of applications where, for example, it is desirable for one or more gases (e.g., one or more precursors) to have a relatively high concentration, a relatively high partial pressure, and/or a relatively high residence time within a reaction chamber; reduction in precursor waste that would otherwise occur is expected; and/or a relatively high absolute pressure within the reaction chamber is desired. By way of example, the exemplary systems, reactors, and methods can be used in Atomic Layer Deposition (ALD) applications where partial pressures and sums of one or more precursors are desiredOr increased concentration, for example, when the precursors reach soft growth rate saturation using typical ALD processing techniques (e.g., using sam.24 precursors and oxygen plasma); for use in ALD reactions where high partial pressures are desired to drive the film formation process and/or reduce undesired by-product formation/poisoning, e.g., using TiCl₄And NH₃Performing ALD to deposit TiN; in reactions where high partial pressures of precursors are desired (e.g., single precursor reactions), such as during the formation of self-assembled monolayers; and conventional ALD processes (e.g., aluminum oxide formation using Trimethylaluminum (TMA) and an oxidizing agent such as water), wherein one or more precursors are typically distributed across the substrate surface using a relatively expensive gas distribution device such as a showerhead. Although the systems, reactors, and methods are described below in the context of an ALD reactor, the systems, reactors, and methods are not limited thereto unless otherwise indicated.

turning now to the drawings, fig. 1-3 illustrate a system 100 according to at least one embodiment of the present disclosure. Fig. 1 shows the system 100 in a loading/unloading position. Fig. 2 shows the system 100 in a processing position. FIG. 3 illustrates a portion of the system 100 in a purge position.

The system 100 includes a gas phase chemical reactor 102 that includes a reaction chamber 104 and a load/unload chamber 106, a first precursor source 107, a second precursor source 108, a purge gas source 110, a gas distribution device 112, a pedestal 114, a vacuum source 116, and a controller 134. The system 100 also includes a valve (e.g., gate valve) 124 to seal the opening 120 in the load/unload chamber 106; and a protective shield 126 to protect the valve 124 from exposure to process gases used within the reaction chamber 104 and purged through the load/unload chamber 106. A valve actuator 136, which may be coupled to the controller 134, may be used to cause the valve 124 to open and close. The system 100 may optionally include a remote plasma unit 144 to activate one or more of the gas precursor sources 1-7, 1-8 and/or the purge/carrier gas source 110. Additionally or alternatively, system 100 may include a direct plasma system, wherein, for example, susceptor 144 or a portion thereof forms an electrode of a direct plasma device, gas distribution device 112 may form another electrode, and/or system 100 may include an inductively coupled plasma device.

As described in more detail below, during operation of the system 100, a substrate (not shown) can be transferred through the opening 120 onto a susceptor within the load/unload chamber 106 and moved into the reaction chamber 104 (e.g., using the shaft 128). During a processing session, the reaction chamber 104 may be isolated from the load/unload chamber 106 and the substrate may be exposed to one or more precursors within the reaction chamber 104 (e.g., from sources 107, 108) while maintaining a vacuum (e.g., a pressure lower than the pressure in the reaction chamber 104) within the load/unload chamber 106. As used herein, the term isolation does not require a complete seal, but also includes a substantial seal and/or tortuous path between the reaction chamber 104 and the load/unload chamber 106 such that gas from the precursor sources 107, 108 cannot flow continuously through the reaction chamber 104, but rather the amount of precursor continues to rise over a period of time and can remain substantially constant during immersion (e.g., within ten percent, five percent, or one percent of the peak minus any reduction due to chemical reactions within the reaction chamber 104). The substrate can remain within the reaction chamber 104 while the precursors are introduced into the reaction chamber 104 and used for the immersion period. As used herein, the immersion period refers to a period of time after the flow of gas from the precursor source is stopped while the reaction chamber 104 is isolated from the load/unload chamber 106 so that the substrate remains in contact with the precursor within the reaction chamber 104 for a period of time after the flow of precursor is turned off. At the end of the immersion period, the substrate is lowered into the load/unload chamber 106. At this point, the reaction chamber 104 can be evacuated using the pressure differential between the reaction chamber 104 and the load/unload chamber 106 and/or the vacuum provided by the vacuum source 116. A purge gas (e.g., from purge gas source 110) may optionally be provided to further facilitate purging of any unreacted precursors and/or byproducts. These steps may be repeated for the same or different precursors until the desired film is formed on the surface of the substrate.

Referring again to fig. 1, the reactor 102 may be formed of, for example, stainless steel, titanium, and/or aluminum, among others. Further, the reactor 102 may be a stand-alone reactor or form part of an integrated tool that may include similar or different reaction chambers. According to an exemplary embodiment of the present disclosure, the reaction chamber 104 is relatively small (e.g.For processing substrates having a diameter of about 300mm, the internal volume of the reaction chamber 104 may be about 0.5 to about 1 or about 0.7dm³). The relatively small internal volume allows for high partial and/or absolute pressures to be quickly reached using relatively small amounts of precursor, which in turn facilitates fast, inexpensive processing of the substrate. According to further examples, the internal volume ratio of the internal volume of the load/unload chamber 106 to the internal volume of the reaction chamber 104 may be relatively high. For example, the volume ratio of the interior volume of the load/unload chamber 106 to the interior volume of the reaction chamber 104 can be in the range of about 5:1 to about 160:1, about 10:1 to about 80:1, or about 20:1 to about 60:1, or greater than 5, 60, or 160. The relatively high volume ratio allows the reaction chamber 104 to be rapidly purged when the load/unload chamber 106 is maintained at a lower pressure than the reaction chamber 104, which in turn facilitates rapid processing of the substrate.

According to some examples of the present disclosure, the load/unload chamber 106 may have a relatively simple design — for example, the bottom portion (the portion below the load/unload chamber where the gate valve is attached to the actuator 136) can have a substantially hollow cylindrical shape with a bottom. This allows the bottom part to be easily removed and replaced and/or cleaned. Additionally or alternatively, the system 100 may include a removable (e.g., disposable) liner, as shown in fig. 7. Additionally or alternatively, the load/unload chamber 106 may include a purge gas inlet near the interface with the reaction chamber 104. Further facilitating purging of any reactants and mitigating contact of the reactants with the inner surface of the load/unload chamber 106. The walls of the load/unload chamber 106 (e.g., one or more of the walls 146, 148, and/or 150) may be heated (e.g., to a temperature above the condensation temperature of the precursors and/or any reaction byproducts) to reduce any condensation thereon.

First precursor source 107 and second precursor source 108 may include any material suitable for gas phase reactions. The precursors within the sources 107, 108 may initially be solid, liquid, or gas. In the case of solids and liquids, the precursor can be converted to the gaseous state by heating, using a bubbler, or the like.

The purge/carrier gas source 110 may comprise any suitable gas or material that becomes capable of purging the reaction chamber 104 and/or a gas suitable as a carrier gas. Exemplary purge and/or carrier gases include argon, nitrogen, and/or hydrogen. When a carrier gas is provided, the carrier gas may be mixed with one or more gases (e.g., from first precursor source 107 and/or second precursor source 108) at and/or before mixer 122. Although the system 100 is shown with two precursor sources and one purge/carrier gas source, the system 100 may include any suitable amount of precursor sources, purge gas sources, and/or carrier gas sources, and in some cases, need not include purge gas sources and/or carrier gas sources. Further, although illustrated as being coupled with the gas distribution device 112, the purge gas source 110 or another purge gas source may additionally or alternatively be coupled with the load/unload chamber 106 to directly purge the load/unload chamber 106 and/or to serve as a gas curtain as described below.

The gas distribution apparatus 112 may be configured to provide vertical (as shown) or horizontal gas flow to the reaction chamber 104. An exemplary Gas mixing and Gas distribution apparatus is described in U.S. patent No. 8,152,922 entitled "Gas Mixer and Manifold Assembly for ALD Reactor" to Schmidt et al, 4/10/2012, the contents of which are incorporated herein by reference to the extent not inconsistent with this disclosure. As an example, the gas distribution system 112 may include a showerhead. However, according to other embodiments, the gas distribution arrangement 112 need not include a showerhead, but may include a relatively simple gas inlet.

the susceptor 114 may be formed of, for example, SiC or SiC-coated graphite. According to some examples of the present disclosure, the pedestal 114 may include apertures to allow the lift pins to retract into the pedestal 114 during processing and extend above the top surface 115 of the pedestal 114 during the substrate transfer process. Exemplary susceptor and lift pin mechanisms are disclosed in U.S. application No. 15/672,096 entitled "SUBSTRATE lift mechanism and REACTOR INCLUDING the SAME," the contents of which are incorporated by reference herein without conflict with the present disclosure.

the vacuum source 116 may include a vacuum source capable of being turned on or offany suitable vacuum source that provides the desired pressure in the chamber 104. The vacuum source 116 may comprise, for example, a dry vacuum pump, either alone or in combination with a turbomolecular pump. According to various examples of the disclosure, the vacuum source 116 is configured to provide about 1 to about 10 to the reactor 102 and, in particular, the load/unload chamber 106^-6About 0.1 to about 10^-4Or about 10^-2To about 10^-3The pressure of the tray. One or more vacuum sources 116 may be coupled to the reaction chamber 104 and/or the load/unload chamber 106.

the valve 124 may comprise any suitable valve, such as a gate valve, to seal the opening 120 in the load/unload chamber 106. According to an exemplary embodiment of the present disclosure, the valve 124 is a gate valve, including a plate 402, as shown in fig. 4. An actuator 136, which may be coupled to the controller 134, may be used to cause the valve 124 to open or close (e.g., move up and down).

The protective shield 126 may be used to protect the valve 124 from reactive species while purging the contents of the reaction chamber 104 to the load/unload chamber 106. The boot 126 may be formed of, for example, stainless steel, titanium, or aluminum, and may have a height (H) and/or length (L) that is slightly (e.g., about 2%, 5%, 10%, 15%, or 20%) greater than the valve 124. As shown in fig. 4, the protective cover 126 may be fixedly or removably attached to the valve 124 using one or more fasteners 404, 406, which may be or include, for example, welds, bolts, screws, and the like. Alternatively, the valve 124 and the boot 126 may have a unitary construction. To further protect the valve 124, a flow of inert gas (e.g., nitrogen, argon, etc.) may be provided (e.g., 25 to 100sccm) between the valve 124 and/or the inner wall 137 of the reactor 102/load/unload chamber 106 and the protective shield 126 to form a gas curtain that prevents or reduces gas from the reaction chamber 104 from reaching the valve 124 during the purging process. Further, the protective cover 126 may be configured such that the protective cover 126 does not contact the inner wall of the loading/unloading chamber 106 when the protective cover 126 is moved. Alternatively, the protective cover 126 may be configured such that when the valve 124 is partially or fully closed, the protective cover 126 forms a hard seal on the topmost interior surface of the load/unload chamber 106 (e.g., over the opening 120), thereby reducing the need for a sealing gas flow.

The shaft 128 may be configured to move up and down to facilitate loading and unloading of substrates through the opening 120 and to move substrates to a processing position within the reaction chamber 104. In some embodiments, the shaft 128 may also rotate during substrate processing and/or during substrate loading/unloading operations; however, in some instances, it may not be necessary or desirable to rotate the shaft 128. The shaft 128 may also receive and retain various wiring, such as heaters, thermocouples, and the like embedded in and/or attached to the pedestal 114. Although the system 100 is described in connection with an axis of upward and downward movement, according to other exemplary embodiments of the present disclosure, the susceptor may move horizontally between the load/unload chamber and the reaction chamber, or the susceptor may remain stationary and the reaction chamber and/or the load/unload chamber may move relative to the susceptor.

In the example shown, the system 100 also includes a protective cover 130 (e.g., a bellows) to seal the shaft 128 and the load/unload chamber 106 from exposure to the environment outside of the reactor 102 and to protect a portion of the shaft and/or components attached thereto from exposure to chemicals.

The system 100 may also include guides 132 to direct the flow of gas from the reaction chamber 104 to the load/unload chamber 106 and away from the valve 120 during the purging process. The guide 132 may be formed of, for example, stainless steel, titanium, or aluminum, and includes an angled or curved surface to direct the flow of gas from the reaction chamber 104 away from the valve 124.

The controller 134 may be coupled to one or more of the shaft 128, the valve actuator 136, and/or the valves 138 and 142, mass flow controllers coupled to one or more of the first precursor source 107, the second precursor source 108, and the purge/carrier gas source 110, etc. to perform the various steps as described herein. For example, the controller 134 may include memory programmed to enable the controller 134 to perform the following steps:

When the susceptor is in the processing position,

Providing the precursor to the reaction chamber while evacuating the load/unload chamber with a vacuum source;

Stopping precursor flow, an

the reaction chamber is evacuated by moving the susceptor into the load/unload chamber.

The memory may be programmed to enable the controller to perform the following steps after stopping the precursor flow:

Exposing the substrate to the precursor in the reaction chamber for an immersion period; and

After the immersion period, the reaction chamber is evacuated by moving the susceptor to the loading/unloading chamber.

Additionally or alternatively, the controller 134 may be configured to cause the system 100 to automatically perform any of the methods described herein.

As mentioned above, fig. 1 shows the system 100 in a loading/unloading position. In this position, the valve 124 is in an open position, allowing a robot or transfer arm 118 to be used to load and/or remove substrates from the surface 115 of the pedestal 114. Once the substrate is loaded onto the susceptor, the valve 124 is closed to seal the load/unload chamber 106 and expose the load/unload chamber 106 (and the reaction chamber 104) to the vacuum source 116. For example, the load/unload chamber 106 may be exposed to the vacuum source 116 to achieve a pressure within the load/unload chamber 106 of about 1 to about 10^-6About 0.1 to about 10^-4Or about 10^-2To about 10^-3and (4) supporting.

After the substrate has been loaded onto the susceptor 114, the susceptor 114 is raised to a processing position, as shown in FIG. 2. In this position, the top surface 115 of the susceptor 114 forms at least a portion or bottom of the reaction chamber 104. One or more precursor gases are flowed across the surface of the substrate once the substrate is in the processing position. The precursor flow is then stopped for an impregnation period. During this time, the partial pressure and/or absolute pressure of the one or more precursors within the reaction chamber 104 can be maintained by sealing the reaction chamber 104 from the load/unload chamber 106. A seal may be formed between the base surface 302 and the inner surface 304 of the reaction chamber 104. The surfaces 302 and 304 may be machined and mated (e.g., with linearly matching inclined surfaces as shown) to provide a substantial seal between the reaction chamber 104 and the load/unload chamber 106.

the susceptor 114 may then be lowered to purge the reaction chamber 104, as shown in FIG. 3. The purge of reaction chamber 104 may be generated at least in part by a pressure differential between load/unload chamber 106 and reaction chamber 104 and/or by supplying a purge gas (e.g., by supplying purge gas from purge gas source 110 through gas distribution device 112).

Fig. 7 illustrates another system 700 according to an exemplary embodiment of the present disclosure. System 700 is similar to system 100, except that system 700 includes a relatively simple inlet 722 instead of gas distribution apparatus 112. The system 700 also includes a reaction chamber 704 defined by an upper surface 702 of the reaction chamber, rather than the gas distribution device. This relatively simple design may make manufacturing easier and/or less expensive relative to system 100. The system 700 also shows a liner 740 and a cooling/condensing plate 716, which may be used to collect precursors and/or byproducts during the purging step. Any combination of liners 740 and cooling/condensing panels 716 may similarly be included in system 100.

fig. 5 shows a method 500 according to an exemplary embodiment of the present disclosure. The method 500 includes loading a substrate onto a susceptor (step 502); closing the valve (step 504); reducing the pressure within the reactor load/unload chamber (step 506); moving the base to a processing position (step 508); optionally reducing, i.e., further reducing, the pressure within the reaction chamber (step 510); initiating a flow of precursor gas (step 512); optionally flowing a carrier gas (step 514) stopping the flow of the precursor gas and optionally stopping the flow of the carrier gas (step 516); dipping the substrate in the presence of one or more precursors (step 518); lowering the pedestal to initiate a purging process (step 520); optionally repeating steps 506-520 for the same or different precursors (step 522); and unloading the substrate (step 524).

during step 502, a valve (e.g., valve 124) is in an open position to allow a substrate to be placed onto a pedestal (e.g., pedestal 114) in a reactor load/unload chamber (e.g., load/unload chamber 106). The valve is then closed during step 504. Once the valve is closed, an inert gas may be provided between the valve or an inner surface of the reactor (e.g., an inner surface of the load/unload chamber) and the protective plate to protect the valve from exposure to chemicals used during substrate processing. Alternatively, the gas curtain may be provided continuously between the valve/inner surface and the protective plate, or at any time prior to the purging process. After the valves are closed, the load/unload chamber and the reaction chamber may be exposed to a vacuum source (e.g., vacuum source 116) to achieve a desired pressure within the reactor and/or the load/unload chamber during step 506. The substrate may then be placed within the reaction chamber by moving the susceptor during step 508, and the reaction chamber may optionally be exposed to the same or a different vacuum source for a period of time during step 510. During step 508, a seal or substantial seal (e.g., a tortuous path) may be formed between the reaction chamber and the load/unload chamber such that relatively little gas flows between these chambers. Alternatively, a small space between the reaction chamber and the loading/unloading chamber may be maintained during a flow-type reaction step that may be performed in addition to or instead of the impregnation step described below. At step 512, one or more precursor gases are flowed over the substrate surface for a period of time. To assist in providing the one or more precursors, heat may be applied to the one or more precursor sources and/or a bubbler may be used. The carrier gas may be flowed in parallel with one or more precursor gases and may be mixed at mixer 122 and/or may be mixed with precursor gases within the precursor sources (e.g., sources 107, 108). According to some examples of the disclosure, the carrier gas flows only for a portion (e.g., the second half) of the time that the precursor gas flows. At step 516, the flow of precursor gas and optionally any carrier gas is stopped for an impregnation period (step 518). During the immersion period, the reaction chamber may be operated non-isothermally — for example, the susceptor may be at one temperature and the top surface of the reaction chamber may be at another temperature, such that the temperature within the reaction chamber changes as the precursor, carrier gas, and/or purge gas is introduced into the reaction chamber. For example, the temperature of the top surface of the reaction chamber may be higher than the temperature of the susceptor, which may cause the surface of the substrate to receive heat from the top surface as the susceptor moves to the processing position. Also, the substrate may cool as it moves away from the top surface. The duration of the dipping period (step 518) may vary depending on the application and may range, for example, from about 0.2 to about 600 seconds, from about 1 to about 60 seconds, or from about 5 to about 30 seconds. After the immersion period, the susceptor is lowered (step 520) so that unreacted precursors and/or reaction byproducts can be blown out of the reaction chamber, through the load/unload chamber and toward the vacuum source. During steps 506 through 520, the reaction chamber and/or the load/unload chamber may continue to be exposed to the vacuum source to facilitate purging the reaction chamber as the base is moved during step 520. For example, the load/unload chamber may be maintained at a desired pressure during one or more of steps 506-518 or 520. Additionally or alternatively, the reaction chamber may be exposed to a vacuum source prior to moving the susceptor; this has the advantage of keeping the load/unload chamber relatively clean. As shown, the method 500 may repeat performing step 506-520 for the same (e.g., for self-assembled monolayers) or different precursors (e.g., different precursors used in ALD deposition). To facilitate the purging step, one or more purging gases may be supplied to the reaction chamber and/or the load/unload chamber. The substrate may then be removed by moving the susceptor to the load/unload position and opening the valve at step 524.

The purge time during step 520 may be relatively short. By way of example, the continuous purge time may be in the range of about 0.1 to about 300 seconds, about 1 to about 60 seconds, or about 2 to about 10 seconds.

It may be desirable to occasionally clean portions of the system, such as the reaction chamber and/or the load/unload chamber. In these cases, the load/unload chamber needs to be cleaned less frequently than the reaction chamber because any deposition reactants are greatly diluted in the load/unload chamber and the residence time of the reactants can be much shorter. Any exemplary cleaning compound includes NF 3.

Fig. 6 shows a pressure diagram illustrating an exemplary pressure 602 within a load/unload chamber (e.g., load/unload chamber 106), a pressure 604 within a reaction chamber (e.g., reaction chamber 104), and a pressure 606 within a precursor source vessel during a process. The process shown begins when the susceptor is in a processing position. As shown, the pressure within the load/unload chamber may be reduced at the beginning of the process and continue to be reduced as the precursor flows until the pressure reaches a low value. The pressure may be maintained at or near a low value until the purging process is initiated, at which time the pressure in the loading/unloading chamber is raised. At the same time, the pressure within the reaction chamber may initially be lower and rise as the precursor and/or carrier gas is introduced into the reaction chamber. In the illustrated example, the carrier gas flow begins after the precursor flow begins. The pressure within the reaction chamber then remains substantially constant during the immersion period and then drops as the substrate moves from the processing position to the purge position (e.g., as shown in fig. 3). The pressure within the reaction chamber may be further reduced to expose the reaction chamber to a vacuum source after the dipping period and before or during the step of moving the susceptor. Also, the pressure within the precursor source vessel may initially be higher (e.g., as a result of heating the vessel) and decrease as the precursor gas is introduced into the reaction chamber. The pressure within the precursor source vessel can then be raised again-e.g., by disconnecting the source precursor from the reaction chamber (e.g., at the beginning of the impregnation period) and/or at the end of the impregnation period.

as noted above, for some types of reactions, it may be desirable for one or more precursors to have a relatively high partial pressure and/or absolute pressure within the reaction chamber. One technique to achieve the desired precursor partial pressure is to heat the precursor source to increase the evaporation rate of the precursor and increase the saturated vapor pressure of the precursor. Additionally or alternatively, a cushion of inert gas may be used to increase the pressure within the reaction chamber during the impregnation period. An exemplary inert gas liner is disclosed in U.S. application No. 12/763,037 entitled "PRECURSOR delivery system," the contents of which are incorporated by reference herein without conflict with the present disclosure. While using a gas cushion does not necessarily increase the precursor dose in the reaction chamber, a gas cushion may be used to increase the total pressure within the reaction chamber, and thus the amount of gas surface collisions may be increased using a precursor gas cushion.

While exemplary embodiments of the present disclosure are set forth herein, it will be understood that the disclosure is not limited thereto. For example, although the apparatus and methods are described in connection with various specific components, the disclosure is not necessarily limited to these configurations. Various modifications, alterations, and enhancements may be made to the apparatus and methods set forth herein without departing from the spirit and scope of the present disclosure.