Multi-station semiconductor processing using independently adjustable pedestal

Abstract

To provide a method and an apparatus for depositing a material onto a substrate in a multi-station deposition apparatus having a first station and a second station.SOLUTION: A method includes the steps of providing a first substrate on a first pedestal at a first station, providing a second substrate on a second pedestal at a second station, and simultaneously, for a first portion of a deposition process, generating a first plasma at the first station while the first pedestal is separated a first distance from a first showerhead at the first station, thereby depositing a first layer of material on the first substrate, and generating a second plasma at the second station while the second pedestal is separated a second distance from a second showerhead at the second station, the second distance being different from the first distance, thereby depositing a second layer of material on the second substrate.SELECTED DRAWING: Figure 8

Description

Technical Field

[0001] (Cross - Reference to Related Applications) The PCT application form is submitted simultaneously with this specification as part of this application. As identified in the simultaneously submitted PCT application form, each application for which this application claims benefit or priority is hereby incorporated by reference in its entirety as if fully set forth herein.

Background Art

[0002] During semiconductor processing operations, a substrate is typically supported on a pedestal inside a processing chamber, and a plasma may be used to deposit one or more layers of material on the substrate. In commercial - scale manufacturing, each substrate or wafer contains many replicas of the particular semiconductor device being fabricated, and many substrates are required to achieve the desired quantity of devices. The commercial viability of semiconductor processing operations depends largely on the uniformity within a wafer and the process - condition reproducibility between wafers. Accordingly, efforts are made to ensure that a given wafer being processed and each portion of each wafer are exposed to the same processing conditions. Variations in processing conditions and semiconductor processing tools can cause variations in deposition conditions, resulting in unacceptable variations in overall processing and manufacturing. Techniques and apparatus for minimizing processing variations are needed.

Summary of the Invention

Means for Solving the Problems

[0003] The systems, methods, and apparatuses of the present disclosure each have several novel aspects, none of which alone causes the desirable attributes disclosed herein. Included among these aspects are at least the following implementations, although other implementations may be shown in the detailed description or become apparent from the discussion provided herein.

[0004] In some embodiments, a method of depositing a material on a substrate in a multi-station deposition apparatus having a first station and a second station may be provided. The method includes providing a first substrate on a first pedestal of the first station, providing a second substrate on a second pedestal of the second station, and, for a first portion of a deposition process, simultaneously generating a first plasma at the first station while the first pedestal is separated from a first showerhead of the first station by a first distance, thereby depositing a first layer of the material on the first substrate, and generating a second plasma at the second station while the second pedestal is separated from a second showerhead of the second station by a second distance different from the first distance, thereby depositing a second layer of the material on the second substrate.

[0005] In some embodiments, the method further includes, simultaneously, for a second portion of the deposition process, generating a third plasma at the first station while the first pedestal is separated from the first showerhead by a third distance different from the first distance, thereby depositing a third layer of the material on the first substrate, and generating a fourth plasma at the second station while the second pedestal is separated from the second showerhead by a fourth distance different from the second distance, thereby depositing a fourth layer of the material on the second substrate.

[0006] In some such embodiments, the difference between the first distance and the third distance may be substantially the same as the difference between the second distance and the fourth distance.

[0007] In some embodiments, the method further includes, simultaneously, for a second layer of the deposition process, generating a third plasma at the first station while the first pedestal is separated from the first showerhead by the third distance, thereby depositing a third layer of the material on the first substrate, and generating a fourth plasma at the second station while the second pedestal is separated from the second showerhead by the third distance, thereby depositing a fourth layer of the material on the second substrate.

[0008] In some embodiments, the first portion includes N deposition cycles, each of the N deposition cycles simultaneously generating a first plasma at a first station while a first pedestal is separated by a first distance, thereby depositing a first layer of material on a first substrate, and generating a second plasma at a second station while a second pedestal is separated by a second distance, thereby depositing a second layer of material on a second substrate, and igniting and extinguishing the first plasma and the second plasma.

[0009] In some such embodiments, the method may further include, for a second portion of a deposition process including X deposition cycles after the first portion, simultaneously in each of the X deposition cycles, generating a third plasma at a first station while a first pedestal is separated by a third distance from a first showerhead, thereby depositing a third layer of material on a first substrate, and generating a fourth plasma at a second station while a second pedestal is separated by the third distance from a second showerhead, thereby depositing a fourth layer of material on a second substrate, wherein each of the X deposition cycles includes igniting and extinguishing the third plasma and the fourth plasma.

[0010] In some such embodiments, the method may further include, for a second portion of a deposition process including Y deposition cycles before the first portion, simultaneously in each of the Y deposition cycles, generating a third plasma at a first station while a first pedestal is separated by a third distance from a first showerhead, thereby depositing a third layer of material on a first substrate, and generating a fourth plasma at a second station while a second pedestal is separated by the third distance from a second showerhead, thereby depositing a fourth layer of material on a second substrate, wherein each of the Y deposition cycles includes igniting and extinguishing the third plasma and the fourth plasma.

[0011] In some such embodiments, the method comprises adjusting a first pedestal between a first distance and a third distance, adjusting a second pedestal between a second distance and a fourth distance, and for a second portion of a deposition process comprising Z deposition cycles, simultaneously, in each of the Z deposition cycles, generating a third plasma at a first station while the first pedestal is separated from a first showerhead by the third distance, thereby depositing a third layer of material on a first substrate, and generating a fourth plasma at a second station while the second pedestal is separated from a second showerhead by the fourth distance, thereby depositing a fourth layer of material on a second substrate, wherein each of the Z deposition cycles includes igniting and extinguishing the third plasma and the fourth plasma.

[0012] In some such embodiments, each N deposition cycle at the first station and the second station comprises: (i) adsorbing a film precursor on the substrate at that station such that the precursor forms an adsorption-limiting layer on the substrate; (ii) removing at least a portion of the non-adsorbed film precursor from the volume surrounding the adsorbed precursor; (iii) generating a plasma at that station after removing the non-adsorbed precursor in (ii) to react the adsorbed film precursor by forming a layer of material on the substrate at that station; and (iv) removing any desorbed film precursor and / or reaction by-products from the volume surrounding the film layer, if present, after reacting the adsorbed precursor.

[0013] In some other such embodiments, the method may further comprise adjusting the first pedestal from the first distance to the third distance and adjusting the second pedestal from the second distance to the fourth distance, wherein during (iii) of each cycle, the first pedestal may be at the first distance and the second pedestal may be at the second distance, and during one or more of (i), (ii), or (iv) of each cycle, the first pedestal may be at the third distance and the second pedestal may be at the fourth distance.

[0014] In some embodiments, the method may further include providing a third substrate on a third pedestal of a third station in a multi-station deposition apparatus. This portion of the deposition process may further include generating a third plasma at the third station while the third pedestal is separated by a third distance that may be different from the first and second distances from the third showerhead of the third station, thereby simultaneously depositing a third layer of material on the third substrate.

[0015] In some such embodiments, for a second portion of the deposition process, simultaneously, a fourth plasma is generated at the first station while the first pedestal is separated by a fourth distance from the first showerhead, thereby depositing a fourth layer of material on the first substrate, a fifth plasma is generated at the second station while the second pedestal is separated by the fourth distance from the second showerhead, thereby depositing a fifth layer of material on the second substrate, and a sixth plasma is generated at the third station while the fourth and fifth plasmas are being generated simultaneously and while the third pedestal is separated by the fourth distance from the third showerhead, thereby depositing a sixth layer of material on the third substrate.

[0016] In some embodiments, the first plasma may have plasma characteristics of a first value and the second plasma may have plasma characteristics of a second value different from the first value.

[0017] In some such embodiments, the plasma characteristics may include plasma power.

[0018] In some embodiments, the first layer of material on the first substrate may have properties of a first value and the second layer of material on the second substrate may have properties of a second value that are substantially the same as the first value.

[0019] In some embodiments, the first layer of material on the first substrate may have a property of a first value, and the second layer of material on the second substrate may have a property of a second value different from the first value.

[0020] In some such embodiments, the property may be a wet etching rate, a dry etching rate, a composition, a thickness, a density, an amount of crosslinking, a chemical property, a reaction completion, a stress, a refractive index, a dielectric constant, a hardness, an etching selectivity, a stability, and a hermeticity.

[0021] In some embodiments, the first layer of material on the first substrate may have a property of a first value, and the second layer of material on the second substrate may have a property of the first value.

[0022] In some embodiments, the method may further include providing a third substrate on a first pedestal before providing the first substrate and the second substrate, and providing a fourth substrate on a second pedestal before providing the first substrate and the second substrate, and, for a second deposition process, simultaneously generating a third plasma at a first station while the first pedestal is separated from a first showerhead by a third distance, thereby depositing a third layer of material on the third substrate, and generating a fourth plasma at a second station while the second pedestal is separated from a second showerhead by a first distance, thereby depositing a fourth layer of material on the fourth substrate, wherein a first non-uniformity between the property of the first layer of material on the first substrate and the property of the second layer of material on the second substrate is smaller than a second non-uniformity between the property of the third layer of material on the third substrate and the property of the fourth layer of material on the fourth substrate.

[0023] In some embodiments, the first pedestal may apply a chucking force to the first substrate during a first portion of the deposition process, and the second pedestal may apply a chucking force to the second substrate during a first portion of the deposition process.

[0024] In some embodiments, a method of depositing a material on a substrate in a multi-station deposition apparatus having a first station and a second station may be provided. The method includes providing a first substrate on a first pedestal of the first station, providing a second substrate on a second pedestal of the second station, and, for a first portion of the deposition process, simultaneously generating a first plasma at the first station while the first pedestal is separated from a first showerhead of the first station by a first distance, thereby depositing a first layer of the material on the first substrate, and generating a second plasma at the second station while the second pedestal is separated from a second showerhead of the second station by the first distance, thereby depositing a second layer of the material on the second substrate. The method may further include, after the first portion, adjusting the first pedestal to a second distance and the second pedestal to the second distance, and, for a second portion of the deposition process, simultaneously generating a third plasma at the first station while the first pedestal is separated by the second distance, thereby depositing a third layer of the material on the first substrate, and generating a fourth plasma at the second station while the second pedestal is separated by the second distance, thereby depositing a fourth layer of the material on the second substrate.

[0025] In some such embodiments, the first layer of material on the first substrate may have a property of a first value, the second layer of material on the second substrate may have a property of a second value, the third layer of material on the first substrate may have a property of a third value different from the first value, and the fourth layer of material on the second substrate may have a property of a fourth value different from the second value.

[0026] In some such embodiments, the first distance may be longer than the second distance.

[0027] In some embodiments, a multi-station deposition apparatus may be provided. The apparatus may include a processing chamber, a first processing station within the processing chamber including a first showerhead and a first pedestal configured to move vertically with respect to the first showerhead, a second processing station within the processing chamber including a second showerhead and a second pedestal configured to move vertically with respect to the second showerhead, and a controller for controlling the multi-station deposition apparatus to deposit material on substrates at the first and second stations. The controller may provide a first substrate to the first pedestal, provide a second substrate to the second pedestal, move the first pedestal so that the first pedestal is separated from the first showerhead by a first distance, move the second pedestal so that the second pedestal is separated from the second showerhead by a second distance, and simultaneously generate a first plasma at the first station while the first pedestal is separated from the first showerhead by the first distance, thereby depositing a first layer of material on the first substrate, and generate a second plasma at the second station while the second pedestal is separated from the second showerhead by a second distance different from the first distance, thereby depositing a second layer of material on the second substrate, and include control logic for doing so.

[0028] In some such embodiments, the controller may further include control logic for moving the first pedestal so that the first pedestal is separated from the first showerhead by a third distance, moving the second pedestal so that the second pedestal is separated from the second showerhead by a fourth distance, and simultaneously generating a third plasma at the first station while the first pedestal is separated from the first showerhead by the third distance, thereby depositing a third layer of material on the first substrate, and generating a fourth plasma at the second station while the second pedestal is separated from the second showerhead by the fourth distance, thereby depositing a fourth layer of material on the second substrate.

[0029] In some such embodiments, the third distance may be different from the fourth distance.

[0030] In some such embodiments, the third distance may be the same as the fourth distance.

[0031] In some other such embodiments, the controller may further include control logic for simultaneously generating a third plasma at a third station and a fourth plasma at a fourth station before simultaneously generating a first plasma at a first station and a second plasma at a second station.

[0032] In some other such embodiments, the controller may further include control logic for simultaneously generating a third plasma at a third station and a fourth plasma at a fourth station after simultaneously generating a first plasma at a first station and a second plasma at a second station.

[0033] In some embodiments, the first pedestal may be configured to apply a chucking force to the first substrate, the second pedestal may be configured to apply a chucking force to the second substrate, and the controller may further include control logic for causing the first pedestal to apply a chucking force to the first substrate and the second pedestal to apply a chucking force to the second substrate during a first portion of the deposition process.

[0034] In some such embodiments, the first chucking force and the second chucking force may be electrostatic forces.

[0035] In some such embodiments, the first chucking force and the second chucking may be applied by a vacuum.

[0036] In some embodiments, a multi-station deposition apparatus may be provided. The apparatus includes a processing chamber, a first processing station within the processing chamber that includes a first showerhead and a first pedestal configured to move vertically with respect to the first showerhead, a second processing station within the processing chamber that includes a second showerhead and a second pedestal configured to move vertically with respect to the second showerhead, and a controller for controlling the multi-station apparatus to deposit material on substrates at the first and second stations. The controller provides a first substrate to the first pedestal, provides a second substrate to the second pedestal, moves the first pedestal so that the first pedestal is separated from the first showerhead by a first distance, moves the second pedestal so that the second pedestal is separated from the second showerhead by the first distance, and simultaneously generates a first plasma at the first station while the first pedestal is separated from the first showerhead by the first distance, thereby depositing a first layer of material on the first substrate, and generates a second plasma at the second station while the second pedestal is separated from the second showerhead by the first distance, thereby depositing a second layer of material on the second substrate, and includes control logic for doing so. The method may further include, after simultaneously generating the first plasma and the second plasma, moving the first pedestal so that the first pedestal is separated from the first showerhead by a second distance, after simultaneously generating the first plasma and the second plasma, moving the second pedestal so that the second pedestal is separated from the first showerhead by the second distance, and simultaneously generating a third plasma at the first station while the first pedestal is separated from the first showerhead by the second distance, thereby depositing a third layer of material on the first substrate, and generating a fourth plasma at the second station while the second pedestal is separated from the second showerhead by the second distance, thereby depositing a fourth layer of material on the second substrate.

[0037] In some such embodiments, the first distance may be longer than the second distance.

[0038] In some embodiments, a multi-station deposition apparatus may be provided. The apparatus may include a processing chamber, a first processing station within the processing chamber that includes a first showerhead and a first pedestal configured to move vertically with respect to the first showerhead, and a second processing station within the processing chamber that includes a second showerhead and a second pedestal configured to move vertically with respect to the second showerhead. The first pedestal may be separated from the first showerhead by a first distance, and the second pedestal may be separated from the second showerhead by a second distance different from the first distance.

[0039] In some embodiments, the apparatus may further include a third processing station within the processing chamber that includes a third showerhead and a third pedestal configured to move vertically with respect to the third showerhead, where the third pedestal is separated from the third showerhead by a third distance that is the same as the first distance.

[0040] In some such embodiments, the apparatus may further include a fourth processing station within the processing chamber that includes a fourth showerhead and a fourth pedestal configured to move vertically with respect to the fourth showerhead, where the fourth pedestal is separated from the fourth showerhead by a fourth distance different from the first distance, the second distance, and the third distance.

[0041] In some such embodiments, the apparatus may further include a fourth processing station within the processing chamber that includes a fourth showerhead and a fourth pedestal configured to move vertically with respect to the fourth showerhead, where the fourth pedestal is separated from the fourth showerhead by a fourth distance that is the same as the first distance or the second distance.

[0042] In some embodiments, the apparatus may further include a third processing station within the processing chamber, including a third showerhead and a third pedestal configured to move vertically with respect to the third showerhead, where the third pedestal is separated from the third showerhead by a third distance different from the first distance and the second distance.

[0043] In some such embodiments, the apparatus may further include a fourth processing station within the processing chamber, including a fourth showerhead and a fourth pedestal configured to move vertically with respect to the fourth showerhead, where the fourth pedestal is separated from the fourth showerhead by a fourth distance different from the first distance, the second distance, and the third distance.

[0044] In some such embodiments, the apparatus may further include a fourth processing station within the processing chamber, including a fourth showerhead and a fourth pedestal configured to move vertically with respect to the fourth showerhead, where the fourth pedestal is separated from the fourth showerhead by a fourth distance that is the same as the first distance, the second distance, or the third distance.

[0045] In some embodiments, a method of depositing a material on a substrate in a multi-station deposition apparatus having a first station and a second station may be provided. The method may include providing a first substrate on a first pedestal of the first station, providing a second substrate on a second pedestal of the second station, and, for a first portion of the deposition process, simultaneously flowing a precursor over the first substrate at the first station while the first pedestal is separated from the first showerhead of the first station by a first distance, and flowing a precursor over the second substrate at the second station while the second pedestal is separated from the second showerhead of the second station by a second distance different from the first distance.

[0046] In some embodiments, the method may further include, simultaneously for a second portion of the deposition process, flowing a precursor over a first substrate at a first station while a first pedestal is separated from a first showerhead by a third distance, and flowing a precursor over a second substrate at a second station while a second pedestal is separated from a second showerhead by a fourth distance different from the second distance.

[0047] In some such embodiments, the first portion may include N deposition cycles, each of the N deposition cycles may include, simultaneously, flowing a precursor over a first substrate at a first station while a first pedestal is separated by a first distance, and flowing a precursor over a second substrate at a second station while a second pedestal is separated by a second distance.

[0048] In some other such embodiments, for a second portion of the deposition process that includes P deposition cycles, the method may further include, simultaneously in each of the P deposition cycles, flowing a precursor over a first substrate at a first station while a first pedestal is separated from a first showerhead by a third distance, and flowing a precursor over a second substrate at a second station while a second pedestal is separated from a second showerhead by a fourth distance.

[0049] In some other such embodiments, for a second portion of the deposition that includes X deposition cycles after the first portion, the method may further include, simultaneously in each of the X deposition cycles, flowing a precursor over a first substrate at a first station while a first pedestal is separated from a first showerhead by a third distance, and flowing a precursor over a second substrate at a second station while a second pedestal is separated from a second showerhead by a third distance.

[0050] In some other such embodiments, the method may further include, for a second portion of the deposition process that includes a deposition cycle of Y before the first portion, flowing a precursor over the first substrate at the first station while the first pedestal is separated from the first showerhead by a third distance during each deposition cycle of Y, and flowing a precursor over the second substrate at the second station while the second pedestal is separated from the second showerhead by the third distance.

[0051] In some embodiments, a method of depositing a material on a substrate in a multi-station deposition apparatus having a first station and a second station may be provided. The method may include providing a first substrate on a first pedestal of the first station, providing a second substrate on a second pedestal of the second station, and, for a first portion of the deposition process, simultaneously flowing a precursor over the first substrate at the first station while the first pedestal is separated from the first showerhead of the first station by a first distance, and flowing a precursor over the second substrate at the second station while the second pedestal is separated from the second showerhead of the second station by the first distance. The method may further include, after the first portion, adjusting the first pedestal to a second distance and the second pedestal to the second distance, and, for a second portion of the deposition process, simultaneously flowing a precursor over the first substrate at the first station while the first pedestal is separated by the second distance, and flowing a precursor over the second substrate at the second station while the second pedestal is separated by the second distance.

[0052] In some embodiments, a method of depositing a material on a substrate in a multi-station deposition apparatus having a first station and a second station may be provided. The method includes providing a first substrate on a first pedestal of a first station, providing a second substrate on a second pedestal of a second station, and for a first portion of a deposition process, simultaneously generating a first plasma at the first station while the first pedestal is separated from a first showerhead of the first station by a first distance, and simultaneously flowing a precursor over the first substrate, thereby depositing a first layer of the material on the first substrate, and generating a second plasma at the second station while the second pedestal is separated from a second showerhead of the second station by a second distance different from the first distance, and simultaneously flowing the precursor over the second substrate, thereby depositing a second layer of the material on the second substrate.

[0053] In the drawings, which are to be regarded in the light of the appended drawings, in which like reference numerals refer to like elements, various implementations disclosed herein are shown by way of example and not as limitations.

Brief Description of the Drawings

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DETAILED DESCRIPTION OF THE INVENTION

[0069] In this application, the terms "semiconductor wafer", "wafer", "substrate", "wafer substrate", and "partially fabricated integrated circuit" are used interchangeably. One of ordinary skill in the art will understand that the term "partially fabricated integrated circuit" may refer to a silicon wafer that is in one of many stages of fabricating an integrated circuit thereon. Wafers or substrates used in the semiconductor device industry typically have a diameter of 200 mm, or 300 mm, or 450 mm. The following detailed description assumes that the present invention is implemented for use with such wafers. However, the present invention is not so limited. The workpiece may be of various shapes, sizes, and materials. In addition to semiconductor wafers, other workpieces that may utilize the present invention include various articles such as printed circuit boards, magnetic recording media, magnetic recording sensors, mirrors, optical elements, and microelectromechanical elements.

[0070] The techniques and apparatus described herein may improve inter-station consistency of the properties of various deposited materials by adjusting the gap between the pedestal and the showerhead during plasma generation. In many plasma-assisted deposition processes, such as atomic layer deposition (ALD) or plasma-enhanced chemical vapor deposition (PECVD), the showerhead and the pedestal are separated by a certain distance or gap, and the plasma is generated inside this gap to facilitate reactions on the wafer. The distance between the showerhead and the pedestal during plasma generation has been found to affect various properties of the materials deposited on the substrate, such as material thickness, dry etch rate (DER), and wet etch rate (WER). Changing or independently controlling the distance between the showerhead and the pedestal at multiple stations for plasma-assisted processing may change the characteristics of the plasma, such as plasma power and the characteristics of the plasma sheath on the wafer. Independently controlling the pedestal height at multiple stations may further affect processes other than plasma, such as precursor materials, during adsorption-limited processes (e.g., ALD) and during gas-phase processes such as CVD including PECVD.

[0071] Because there is a relationship between the distance and the properties of the resulting material and plasma characteristics, the techniques and apparatuses of this specification utilize pedestals at different distances from the showerhead to adjust the properties of the deposited material and reduce station-to-station variations. In some embodiments, by changing the showerhead-pedestal gap to adjust the properties of the material at one or more stations with respect to one or more other stations, the difference in the properties of the material between stations can be reduced, and as a result, the properties of the material can be adjusted at one or more stations. In certain embodiments, the pedestal distance is adjusted during deposition (e.g., during the process of depositing a layer by a number of cycles of ALD) to create a film having different values of properties throughout the material. For example, the distance can be adjusted during deposition so that within the material, one section of the material has properties of one value, such as density, WER, or DER of one value, and another section of the material has properties of another value.

[0072] I. Examples of Deposition Apparatuses One or more layers of material are deposited on a substrate using several semiconductor processes. Examples of deposition processes include chemical vapor deposition ("CVD"), plasma CVD ("PECVD"), atomic layer deposition ("ALD"), low pressure CVD, ultra-high vacuum CVD, physical vapor deposition ("PVD"), and conformal film deposition ("CFD"). Some CVD processes may deposit a film on the wafer surface by flowing one or more gas reactants into the reactor, thereby forming film precursors and by-products. The precursors are transferred to the wafer surface, adsorbed by the wafer at the wafer surface, diffused into the wafer, and deposited on the wafer by chemical reactions including plasma generation in PECVD. Some other deposition processes involve a number of film deposition cycles that each create a "separate" film thickness. ALD is one such film deposition method, but any technique used in an iterative sequential matter that places thin layers of film underneath can be considered to involve a number of deposition cycles.

[0073] As device sizes and feature sizes continue to shrink in the semiconductor industry, and 3D device structures are increasingly recognized in integrated circuit (IC) design, the ability to deposit thin conformal films (even if not flat, a film of material having a uniform thickness with respect to the shape of underlying structures) has continued to increase in importance. ALD is an optimal film-forming technique for conformal deposition due to the fact that a single thin film of material is deposited in only a single cycle of ALD, and the thickness is limited by the amount of one or more film precursor reactants that may be adsorbed on the substrate surface prior to the film-forming chemical reaction itself (i.e., forming an adsorption-limiting layer). In this case, multiple "ALD cycles" are used to build up a film of the desired thickness, and since each layer is thin and conformal, the resulting film substantially matches the shape of the underlying device structure. In certain embodiments, each ALD cycle includes the following steps. 1. Expose the substrate surface to a first precursor. 2. Purge the reaction chamber in which the substrate is disposed. 3. Activate the reactants on the substrate surface, typically using plasma and / or a second precursor. 4. Purge the reaction chamber in which the substrate is disposed.

[0074] The duration of each ALD cycle may typically be less than 25 seconds, or less than 10 seconds, or less than 5 seconds. One or more plasma exposure steps of the ALD cycle may consist of short durations, such as a duration of 1 second or less. The plasma may consist of other durations longer than 1 second, such as 2 seconds, 5 seconds, or 10 seconds in an example.

[0075] FIG. 1 depicts a substrate processing apparatus for depositing a film on a semiconductor substrate using any number of processes. The apparatus 100 of FIG. 1 has a single processing chamber 110 with a single substrate holder 118 (e.g., pedestal) within an internal volume that may be maintained under vacuum by a vacuum pump 130. Also fluidly connected to the chamber for delivering (e.g.) film precursors, carrier gases and / or purge gases and / or process gases, secondary reactants, etc. are a gas delivery system 102 and a showerhead 104. Further, FIG. 1 also shows facilities for generating plasma inside the processing chamber. The apparatus schematically illustrated in FIG. 1 is generally for performing ALD, but may be adapted for performing other film deposition operations such as conventional CVD, particularly plasma CVD.

[0076] For clarity, the processing apparatus 100 is depicted as a stand-alone processing station having a processing chamber body 110 for maintaining a low-pressure environment. However, as described herein, it will be appreciated that a plurality of processing stations may be included within a common processing tool environment, e.g., within a common reaction chamber. For example, FIG. 2 depicts an implementation of a multi-station processing tool and will be discussed in more detail below. Further, in some implementations, it will be appreciated that one or more hardware parameters of the processing apparatus 100, including the hardware parameters discussed in detail herein, may be programmatically adjusted by one or more system controllers.

[0077] The processing station 110 is in fluid communication with a gas delivery system 102 for delivering a process gas that may include liquids and / or gases to a distribution showerhead 104. The gas delivery system 102 includes a mixing vessel 106 for mixing and / or conditioning the process gas for delivery to the showerhead 104. One or more mixing vessel inlet valves 108 and 108A may control the introduction of the process gas into the mixing vessel 106.

[0078] Some reactants may be stored in liquid form before vaporization and after delivery to the processing chamber 110. The implementation of FIG. 1 includes a vaporization point 112 for vaporizing the liquid reactants supplied to the mixing vessel 106. In some implementations, the vaporization point 112 may be a heated liquid injection module. In some other implementations, the vaporization point 112 may be a heated vaporizer. In yet other implementations, the vaporization point 112 may be excluded from the processing station. In some implementations, a liquid flow controller (LFC) may be provided upstream of the vaporization point 112 to control the mass flow of the liquid to be vaporized and delivered to the processing chamber 110.

[0079] The showerhead 104 delivers a processing gas and / or reactant (e.g., a film precursor) towards the substrate 114 at the processing station, and the flow of the processing gas and / or reactant is controlled by one or more valves (e.g., valves 108, 108A, and 116) upstream of the showerhead. In the implementation shown in FIG. 1, the substrate 114 is disposed below the showerhead 104 and shown resting on the pedestal 118. The showerhead 104 may have any suitable shape and may have any suitable number and arrangement of ports for distributing the processing gas to the substrate 114. In some implementations with two or more stations, the gas delivery system 102 can independently control the flow of the processing gas and / or reactant to each station such that the gas may flow to one station but not to another, including valves or other flow control structures upstream of the showerhead. Further, the gas delivery system 102 may be configured to independently control the processing gas and / or reactant delivered to each station within a multi-station apparatus such that the gas composition provided to different stations is different, e.g., the partial pressures of the gas composition may vary simultaneously between stations.

[0080] In FIG. 1, the showerhead 104 and pedestal 118 are electrically connected to an RF power supply 122 and a matching network 124 to supply power to the plasma. In some implementations, the plasma energy may be controlled by controlling one or more of the process station pressure, gas concentration, RF source power, RF source frequency, and plasma power pulse timing (e.g., via a system controller having appropriate machine-readable instructions and / or control logic). For example, the RF power supply 122 and the matching network 124 may be operated at any suitable power to form a plasma having a desired radical species composition. Similarly, the RF power supply 122 may provide RF power at any suitable frequency and power. The apparatus 100 also includes a DC (direct current) power supply 126 configured to provide direct current to the pedestal, which may be the ESC 118, to generate an electrostatic clamping force and provide it to the electrostatic chuck (ESC) 118 and the substrate 114. The pedestal 118 may also have one or more temperature control elements 128 configured to heat and / or cool the substrate 114. The pedestal 118 is also configured to raise and lower to various heights or distances as measured between the pedestal surface and the showerhead. This includes positioning at different heights during deposition processing. In addition to the mobility of the pedestal 118, the pedestal 118 may also have features similar to other pedestals, such as a standard pedestal made of aluminum or ceramic with a heating feature configured to heat the pedestal up to between about 100°C and 650°C, or a coolant pedestal with a cooling feature configured to cool the pedestal to a temperature below 100°C.Some examples of pedestals are now U.S. Patent No. 7,941,039, U.S. Patent Application Publication No. 11 / 851,310, filed September 6, 2007, entitled "PEDESTAL HEAT TRANSFER AND TEMPERATURE CONTROL", and now U.S. Patent No. 9,337,067, U.S. Patent Application Publication No. 13 / 467,861, filed May 9, 2012, entitled "HIGH TEMPERATURE ELECTROSTATIC CHUCK WITH RADIAL THERMAL CHOKES".

[0081] In some embodiments, the pedestal described herein may be configured to hold a wafer in place. This may include a pedestal that uses some other type of clamping force that increases frictional loading between the wafer and the pedestal / chuck to enhance gravity to prevent relative movement between the wafer and the pedestal / chuck. One type of chuck used in such operations is an "electrostatic chuck", or ESC. Some ESCs hold a wafer in place by applying a direct current ("DC") voltage to one or more clamping electrodes within the ESC such that the wafer and the one or more clamping electrodes act as a capacitive circuit, which is completed by the presence of plasma within the chamber, so this design may be limited to use within a processing chamber where a plasma environment exists during wafer processing. The one or more clamping electrodes are typically thin, flat structures parallel to the entire plane of the wafer and often extend over an area equal to the wafer size. The electrostatic force generated due to the capacitive effect provides the clamping force. Such a configuration is sometimes referred to as "monopolar". Another type of chuck is a chuck that uses a gas flow within the pedestal to create a pressure drop, or vacuum, between the wafer and the pedestal, and the pressure drop then creates an attractive force that clamps the wafer to the pedestal. This may be considered the chucking force applied by the vacuum.

[0082] In some implementations, the apparatus may be controlled using appropriate hardware and / or appropriate machine-readable instructions within a system controller that provides control instructions via a series of input / output control (IOC) instructions. In one example, instructions for plasma ignition or for setting plasma conditions for plasma maintenance are provided in the form of a plasma activation recipe within a process recipe. In some cases, the process recipes are arranged in sequence such that all instructions for a process are executed concurrently in that process. In some implementations, instructions for setting one or more plasma parameters may be included in a recipe that precedes the plasma process. For example, a first recipe may include instructions for setting the flow rate of an inert gas (e.g., helium) and / or a reactant gas, instructions for setting the power set point of a plasma generator, and a time delay instruction for the first recipe. A subsequent second recipe may include instructions for enabling the plasma generator and a time delay instruction for the second recipe. A third recipe may include instructions for disabling the plasma generator and a time delay instruction for the third recipe. It will be appreciated that these recipes may be further subdivided and / or repeated in any suitable manner within the scope of the present disclosure.

[0083] As described above, a multi-station substrate processing tool may include two or more processing stations. FIG. 2 depicts an example of a multi-station processing apparatus. Various efficiencies may be achieved by using a multi-station processing apparatus such as that shown in FIG. 2, not only in terms of equipment costs and operating costs, but also in terms of throughput increase. In an example, a single vacuum pump may be used to create a single high-vacuum environment for all four processing stations, such as by exhausting used process gas, etc. for all four processing stations. Depending on the implementation form, each processing station may have its own dedicated showerhead for gas delivery, but may share the same gas delivery system. Similarly, certain elements of the plasma generator equipment may be shared among the processing stations (e.g., the power supply), but depending on the implementation form, certain aspects may be specific to a processing station (e.g., when applying a plasma generation potential using a showerhead). Again, it should be understood that such efficiencies may also be achieved to a greater or lesser extent by using more or fewer processing stations per processing chamber, such as 2, 3, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, or 16, or even more processing stations per reaction chamber.

[0084] The substrate processing apparatus 200 of FIG. 2 employs a single substrate processing chamber 210 that encompasses a number of substrate processing stations, and each of the number of processing stations may be used to perform a processing operation on a substrate held, for example, on a pedestal, in that processing station, by a wafer holder. In this particular implementation form, the multi-station substrate processing apparatus 200 is shown as having four processing stations 231, 232, 233, and 234. Other similar multi-station processing apparatuses may have more or fewer processing stations depending on the implementation form, for example, depending on the desired parallel wafer processing level, size / space constraints, cost constraints, etc. Also shown in FIG. 2 are a substrate handler robot 236 and a controller 238.

[0085] As shown in FIG. 2, the multi-station processing tool 200 has a substrate loading port 240 and a robot 236 configured to move substrates from a cassette loaded through pod 242 into the processing chamber 210 through the atmosphere port 240 and onto one of four stations 231, 232, 233, or 234.

[0086] The depicted processing chamber 210 shown in FIG. 2 provides four processing stations 231, 232, 233, or 234. The height or distance of the pedestal at each of these stations is individually controllable such that the pedestal can be raised or lowered to a different distance from any of the other pedestals.

[0087] RF power is generated by an RF power system 222 and distributed to each of stations 231, 232, 233, or 234. Similarly, a DC power supply 226 is distributed to each of the stations. The RF power system may include one or more RF power supplies, such as a high frequency (HFRF) source and a low frequency (LFRF) source, an impedance matching module, and a filter. In certain implementations, the power supply may be limited to only a high frequency source or a low frequency source. The distribution system of the RF power system may be symmetric with respect to the reactor and may have a high impedance. As a result of this symmetry and impedance, approximately equal amounts of power are delivered to each station.

[0088] FIG. 2 also depicts an implementation of substrate transfer equipment 290 for transferring substrates between processing stations 231, 232, 233, and 234 inside the processing chamber 214. It will be appreciated that any suitable substrate transfer equipment may be employed. Non-limiting examples include wafer carousels and wafer handling robots.

[0089] FIG. 2 also depicts the processing conditions and hardware state of the processing tool 200, as well as the implementation of the system controller 238 employed to control the processing stations of the processing tool 200. The system controller 238 may include one or more memory elements 244, one or more mass storage devices 246, and one or more processors 248. The processor 248 may include one or more CPUs, ASICs, one or more general-purpose computers and / or one or more dedicated computers, one or more analog and / or digital input / output connections, one or more step motor controller boards, etc.

[0090] The system controller 238 may execute machine-readable system control instructions 250 on the processor 244, and in some implementations, the system control instructions 250 are loaded from the mass storage device 246 into the memory element 244. The system control instructions 250 may include instructions for controlling timing, the mixing of gas and liquid reactants, the pressure of the chamber and / or station, the temperature of the chamber and / or station, the wafer temperature, the target power level, the RF power level, the RF exposure time, and the DC power and duration for clamping the substrate, substrate pedestal, chuck, and / or susceptor position, plasma formation at each station, the flow of gas and liquid reactants, the vertical height of the pedestal, and other parameters of the specific processes performed by the processing tool 200. These processes may include, but are not limited to, various types of processes related to depositing a film on a substrate. The system control instructions 258 may be configured in any suitable manner.

[0091] In some implementations, the system control software 258 may include input / output control (IOC) instructions for controlling the various parameters described above. For example, each step of one or more deposition processes may include one or more instructions for the system controller 250 to execute. For example, instructions for setting processing conditions for a primary film deposition process may be included in the corresponding deposition recipe, and similarly, instructions for setting processing conditions for a capping film deposition may be included in the corresponding deposition recipe. In some implementations, the processing recipes are arranged continuously, such that all instructions for a process are executed concurrently in that process.

[0092] In some implementations, other computer-readable instructions and / or programs stored in the mass storage device 254 and / or the memory element 256 associated with the system controller 250 may be employed. Examples of programs or sections of programs include a substrate positioning program, a process gas control program, a pressure control program, a heater control program, and a plasma control program.

[0093] In some implementations, a user interface may exist associated with the system controller 250. The user interface may include a display screen, graphical software displays of the apparatus and / or processing conditions, and user input devices such as a pointing device, keyboard, touch screen, microphone, and the like.

[0094] In some implementations, the parameters adjusted by the system controller 250 are related to the processing conditions. Non-limiting examples include the composition and flow rate of the process gas, temperature, pressure, plasma conditions (RF bias power level, frequency, exposure time, etc.). Additionally, the controller may be configured to independently control conditions within the processing station. For example, the controller may provide instructions to ignite the plasma at some stations but not all stations. These parameters may be provided to the user in the form of a recipe that may be input using the user interface.

[0095] Signals for monitoring the processes may be provided from various process tool sensors via the analog and / or digital input connections of the system controller 250. Signals for controlling the processes may be output to the analog and / or digital output connections of the process tool 200. Non-limiting examples of process tool sensors that may be monitored include mass flow controllers (MFCs), pressure sensors (such as pressure gauges), thermocouples, load sensors, OES sensors, metrology equipment for measuring the physical properties of waves in-situ, and the like. Using the data obtained from these sensors along with appropriately programmed feedback and control algorithms, the process conditions may be maintained.

[0096] The system controller 250 may provide machine-readable instructions for implementing the deposition process. The instructions may control various process parameters such as DC power levels, RF bias power levels, inter-station variations such as RF power parameter variations, frequency adjustment parameters, pressure, temperature, and the like. The instructions may control the parameters to operate the in-situ film stack deposition in accordance with the various implementations described herein.

[0097] The system controller typically includes one or more memory elements and one or more processors configured to execute machine-readable instructions such that the apparatus performs the operations according to the processes disclosed herein. A machine-readable non-transitory medium containing instructions for controlling the operations according to the substrate doping processes disclosed herein may be coupled to the system controller.

[0098] As mentioned above, throughput can be increased by processing multiple substrates at multiple processing stations within a common substrate processing chamber, which enables parallel film deposition on multiple substrates while simultaneously using common processing equipment among the various stations. Some multi-station substrate processing tools can be used to process wafers simultaneously during equal numbers of cycles (e.g., in some ALD processes). Given this configuration of processing stations as well as substrate loading and transfer equipment, various processing sequences are possible that enable film deposition, for example in the illustrative example, N cycles of film deposition for ALD processing or equivalent exposure durations for CVD processing, to be performed in parallel (e.g., simultaneously) across multiple substrates.

[0099] As discussed above, various efficiencies may be achieved by using a multi-station processing apparatus with respect to not only equipment costs and operating costs but also throughput increase. However, as a result of processing multiple substrates simultaneously in a common chamber, differences between deposited materials may result, including, for example, differences in average film thickness, differences in uniformity across the entire wafer surface, differences in physical properties such as wet etching rate (WER) and dry etching rate (DER), differences in chemical properties, and differences in optical properties. There may be various thresholds for acceptable inter-station deviations in material properties, but it is desirable to reduce these differences in order to repeatedly produce uniform substrates for commercial-scale manufacturing.

[0100] Use various handling means to achieve stable film deposition across different substrates. Some of these handling means include indexing the substrate through a number of processing stations inside the processing chamber over the course of the deposition process, i.e., depositing a portion of the film of the substrate at one station for each substrate and a portion at one or more other processing stations. As a result, any systematic differences in deposition occurring at different stations are averaged out. For example, in an ALD process performing a total of N cycles on four wafers in a four-station processing chamber, N / 4 cycles can be performed on each wafer at each station, and each wafer is transferred to a different station after each completion of N / 4 cycles. This type of "sequential mode" processing or "sequential processing" is beneficial in several ways, but other characteristics of this operating mode make this operating mode less appealing. For example, some implementations of the sequential mode involve a significant amount of substrate loading / unloading and opening / closing of the processing chamber. In some operating modes, the processing chamber has to be opened and closed four times for the loading / unloading operation in order for the substrate to receive N depositions assigned to itself across four stations, and each time, it involves restoring the environment inside the chamber to environmental conditions suitable for deposition (e.g., temperature, pressure, flow rate, etc.).

[0101] The "static mode" may involve the same amount of indexing to place four wafers into positions for deposition using a 90° transfer rotation of the cassette in which the wafers are placed inside the processing chamber when using one station for the loading operation, but in the static mode, intervening depositions are not performed during the transfer rotation, so the chamber is opened and closed only once. As a result, it is also possible to load all four wafers (one by one) into the multi-station chamber before deposition. Even when the chamber remains closed and the internal pressure remains relatively static, the indexing of the wafers from one station to the next delays the process.

[0102] Since sequential processing and static mode processing involve time and activity, it may be advantageous to utilize another processing sequence, herein called "fixed mode", that involves no indexing at all. In fixed mode, the chamber is opened, wafers are loaded onto all of the stations, the chamber is closed, and all depositions are performed in parallel and simultaneously on all of the wafers while the wafers remain at their respective corresponding stations, the deposition cycle is completed, the chamber is opened, and the wafers are removed. Thus, each substrate receives all of its film depositions while positioned at only one of the processing stations. This fixed mode processing may be used for any type of deposition process including, for example, CVD and ALD. The fixed mode processing results in a higher deposition throughput since there are no delays associated with indexing in other modes.

[0103] As stated above, the fixed mode does not always achieve consistent film deposition between different substrates due to processing inconsistencies between different stations. For example, processing conditions at one station, such as different RF frequencies between stations or different temperatures at each station, may not exactly match the processing conditions at another station, and as a result, wafers processed at one station may have different properties than wafers processed at another station.

[0104] II. Relationship between the properties of the deposited material and the showerhead - pedestal distance As stated explicitly above, this specification describes techniques and apparatus for improving inter-station alignment of the properties of various deposited materials by adjusting the gap between the pedestal and the showerhead during plasma generation. In many plasma-assisted deposition processes such as ALD or PECVD, the showerhead and pedestal are separated by a certain distance or gap, and the plasma is generated within this gap to facilitate reactions on the wafer. Unless otherwise stated herein, the term "gap" or "distance" refers to this spatial relationship between the showerhead and the pedestal, and additionally, the gap or distance of a station is synonymous with the gap or distance of the pedestal. FIG. 3 depicts a schematic cross-sectional view of a dual-station processing chamber of a substrate processing tool. Each station of FIG. 3 may include the same features described above in FIGS. 1 and 2, but only shows some features for illustration purposes. In this case, the first station includes a showerhead 104A and a pedestal 118A separated by a first distance D1, and similarly the second station includes a showerhead 104B and a pedestal 118B separated by a first distance D2, which is the same as D1 in this example. This gap or distance may be measured between the outer surface of the showerhead, such as a faceplate, and the outer surface of the pedestal, such as the surface supporting the substrate.

[0105] The distance between the showerhead and the pedestal during plasma generation has been found to affect various properties of the material deposited on the substrate, such as material thickness, DER, and WER. Figure 4 plots the material thickness for substrates processed at different distances between the showerhead and the pedestal. In the data of Figure 4, four sets of four substrates each were processed in a four-station chamber. Each set was positioned at a different distance from the other sets, and the remaining processing conditions were the same. The average thickness of the material measured on the 16 substrates is shown in Figure 4, where the horizontal axis is the distance in inches between the pedestal and the showerhead, and the vertical axis is the average thickness of the material deposited on the substrate. As can be understood, the overall thickness of the deposited material decreased as the gap decreased. In the example, set 4 with a maximum gap of approximately 0.657 inches (16.7 mm) resulted in an average thickness of the deposited material between about 302 angstroms (Å) and 300 Å, while for a shorter distance of 0.505 inches (12.8 mm), set 3 resulted in a material thickness between 298 Å and 300 Å, and for the minimum distance of 0.020 inches (0.508 mm), set 1 resulted in a material thickness between 288 Å and 290 Å.

[0106] Figure 5 plots the wet etching rate (WER) for substrates processed at different distances between the showerhead and the pedestal. Materials were deposited on eight substrates under the same conditions except that the distance was different for all eight substrates. The average WER measured for the material on each substrate is shown in Figure 5, where the horizontal axis is the distance in inches between the pedestal and the showerhead, and the vertical axis is the average WER of the material deposited on the substrate. As can be understood, the WER changes as the distance changes, and similar to the material thickness shown in Figure 4, generally the WER decreases as the distance decreases, but with some non-linear variations. In the example, the WER at a distance of 0.320 inches (8.13 mm) is smaller than the WER at distances of 0.340 inches (8.64 mm) and 0.300 inches (7.62 mm).

[0107] Changing the distance between the pedestal and the showerhead may also change the characteristics of the plasma, such as the plasma power and the plasma sheath. This was found by correlating the data in FIG. 4 above regarding material thickness versus pedestal distance with the data of materials deposited at different power levels while the distance remained static. In one example seen in FIG. 6, the power was increased while all other processing conditions remained the same, including the distance that included reducing the deposited thickness. FIG. 6 plots the material thickness for substrates processed at different power levels. In this case, material was deposited on 11 substrates, including being at the same distance, with the deposition conditions remaining the same and the power being varied for each deposition process. The average thickness of the material measured for each substrate is shown, with the horizontal axis being the plasma power in watts (W) and the vertical axis being the average thickness of the material deposited on the substrate. As can be understood, as the plasma power decreased, the average thickness on the substrate decreased. When interpreted together with the data in FIG. 4 showing that reducing the gap reduces the deposited thickness, FIGS. 6 and 4 suggest an inverse correlation between the distance and the plasma power such that reducing the gap increases the power applied to the substrate on the pedestal. Based on this relationship, the power applied to the substrate can be adjusted by adjusting the gap.

[0108] III. Examples of Techniques Due to the relationship between the distance and the properties of the resulting material and plasma characteristics, the techniques and apparatus herein utilize pedestals at different distances to adjust the properties of the deposited material and reduce inter-station variations. In some embodiments, to adjust the properties of the material at one of the stations, the difference in the properties of the material between stations can be reduced by changing the gap between the showerhead and the pedestal, which may be considered as adjusting the properties of the material at that station. Additionally, the distance can be adjusted during deposition to create films with different property values throughout the material. For example, during deposition, the distance can be adjusted to have one value of a property, such as density, WER, or DER, in one section of the material and another value of the property in another section of the material within the material. The step of positioning the pedestals at different distances relative to each other during deposition may be implemented in various ways.

[0109] Thus, in some embodiments, the pedestal distance can include changing the distance during deposition and can be different relative to each other throughout the deposition. This can include (i) the pedestals starting at different distances from each other and remaining at these different distances for the entire deposition, (ii) the pedestals starting at the same distance from each other and then changing to different distances in subsequent deposition processes, (iii) the pedestals starting at different distances and then changing to the same distance in subsequent deposition processes, (iv) the pedestals starting at different distances and then changing to other different distances in subsequent deposition processes, and (v) being at different distances within each deposition cycle. In some other embodiments, the pedestals can remain at the same distance relative to each other throughout the deposition, but the distance can be changed relative to the showerhead throughout the deposition.

[0110] A. Examples of Techniques Using Pedestals at Different Distances In a first example of the technique, the distances may be adjusted or regulated prior to deposition such that two or more pedestals are at different distances from each other prior to deposition and remain at these different distances throughout all deposition processes. FIG. 7 depicts a schematic cross-sectional view of a dual-station processing chamber of a substrate processing tool according to various embodiments. In this case, the same chamber as in FIG. 3 is depicted, but the first pedestal and the second pedestal are shown at different distances from each other, with a first distance D1 being shorter than a second distance D2. FIG. 8 depicts a first example of a technique for performing film deposition in a multi-station semiconductor processing chamber, and this technique is described using the chamber of FIG. 7. At block 801, a first substrate 114A is positioned on a first pedestal 118A of a first station, and at block 803, a second substrate 114B is positioned on a second pedestal 118B of a second station. Although not depicted in FIG. 8, the distance of each pedestal may be adjusted before or after positioning a substrate on the pedestal. In some additional embodiments, blocks 801 and 803 may be performed in reverse order or simultaneously.

[0111] When these pedestals are in their corresponding different positions, in order to deposit materials simultaneously on both the first substrate 114A and the second substrate 114B, plasma may be generated simultaneously at the first station and the second station. This simultaneous plasma generation and deposition is represented by block 805 which includes blocks 805A and 805B. In block 805A, the first plasma is generated at the first station, while in block 805B, the second plasma is generated simultaneously at the second station. As further shown in blocks 805A and 805B, by this simultaneous plasma generation, a first layer of material is deposited on the first substrate 114A and a second layer of material is deposited on the second substrate 114B. As used herein, a "layer" of material may include a number of sub-layers of the material, may be the entire layer of material deposited after the deposition process is completed, and may further include a single and distinct layer or sub-layer of material, such as a single and distinct layer of material deposited by ALD. In some embodiments, these first and second layers may have substantially the same characteristics as each other, such as WER, DER, and thickness (substantially the same means, for example, within a range of 10%, 5%, 1%, 0.5%, or 0.1% of each other). As a result, better alignment between stations may be provided such that stations at different distances create the same overall material thickness.

[0112] In an example, if the thicknesses between two stations do not match within a certain threshold range of each other, the distance can be adjusted at one of the stations, and at the adjusted station, the deposited thickness can be changed so that the thicknesses become closer together. For example, referring to FIG. 4, at a distance of 0.35 inches (8.89 mm), station 3 has an average thickness of about 297 Å, while station 1 has an average thickness of slightly less than 296 Å. This variation can be reduced by increasing the distance of station 1 (marked by the dashed line and x in FIG. 4) to about 0.45 so that the deposited thickness at station 1 becomes approximately the same as the thickness at station 3, which is about 297 Å. Thus, in this example, while station 3 is at a distance of 0.35 inches (8.89 mm) and station 1 is at a distance of 0.45 inches (11.4 mm), the simultaneous plasma generation and deposition of blocks 805A and 805B may be performed simultaneously to create deposited materials having substantially the same thickness.

[0113] In some embodiments, these first and second layers may have different properties from each other, such as different densities or thicknesses. As a result, it may still result in better alignment with respect to other material properties. In an example, the materials may have different densities from each other, but may still result in the same thickness (which may be due to other processing conditions such as deposition rate).

[0114] In some embodiments, the pedestal may be at a different distance for only a part of the deposition process in order to change the properties of only a part of the deposited material. Depositing first and second layers with different properties may be advantageous for finely tuning the properties of only one part of the deposited material.

[0115] In a second example of the technique illustrated in FIG. 9, in some implementations, the pedestals may start at the same distance from each other and then be changed to different distances in subsequent deposition processes. FIG. 9 depicts a second example of a technique for performing film deposition in a multi-station semiconductor processing chamber. Blocks 901-905 are the same as blocks 801-805 in FIG. 8, but as illustrated in FIG. 9, prior to the simultaneous plasma generation and deposition of block 905, at block 907, while the pedestals are positioned at the same distance, materials are simultaneously deposited on two substrates. As can be understood, at block 907A, the first pedestal is at a third distance, and at block 907B, the second pedestal is at the same third distance. After performing the simultaneous plasma generation and deposition of block 907, at block 909, the first pedestal is adjusted to a first distance and the second pedestal is adjusted to a second distance. After this adjustment, the simultaneous plasma generation and deposition of block 905 is performed, during which the first pedestal and the second pedestal are at different distances.

[0116] FIGS. 10A-10E, which depict an example of the sequence of pedestal movement in an example of a multi-station processing chamber, further illustrate the second technique. The chambers of FIGS. 10A-10E are similar to the chambers of FIGS. 3 and 7 and have significant differences with respect to distance. As pointed out above, the pedestals within the chambers of FIGS. 10A-10E are movable pedestals configured to be moved and positioned at various distances. In FIG. 10A, the first station and the second station are both at a third distance corresponding to block 907 of FIG. 9. After the deposition of block 907, block 909 is performed to move the pedestals as seen in FIG. 10B. In this case, in FIG. 10B, the first pedestal is at a first distance and the second pedestal is at a second distance. When positioned as such in FIG. 10B, the simultaneous plasma generation and deposition of block 905 of the second example of the technique may be performed. In this example of the technique, the first distance, the second distance, and the third distance are all different from each other.

[0117] In some other embodiments, the pedestals may be at different distances for the first part of the full deposition process and then changed to the same distance for the second part of the deposition process. In this third example of the technique, blocks 905 and 907 are exchanged and block 909 is modified. In this case, blocks 901, 903, and 905 are sequentially performed such that the first simultaneous plasma generation and deposition on the first and second substrates is performed while the first pedestal and the second pedestal are at different distances. After performing block 905, a modified block 909 is performed that adjusts the distance of the pedestals so that the pedestals are at the same third distance, and then the simultaneous plasma generation and deposition of block 907 is performed. Referring back to the illustrations of FIGS. 10A and 10B, the third example of the technique may first be positioned as depicted in FIG. 10B and then subsequently positioned as depicted in FIG. 10A.

[0118] In some other embodiments, the simultaneous plasma generation and deposition may first be performed on the substrates while the substrates are at the same distance and then subsequently only one of the pedestal distances is adjusted. In the fourth example of the technique, referring to FIG. 9, blocks 901, 903, and 907 may be sequentially performed, but block 909 is different in that it adjusts only the distance of the first pedestal to a first distance while the second pedestal remains at a second distance. In this example, the first distance and the third distance are different from each other and the second distance is the same as the third distance. Following this adjustment, the simultaneous plasma generation and deposition of block 905 is performed while the first pedestal is at a different distance from the second pedestal, but the second pedestal is at the same distance as in block 907.

[0119] In some such embodiments, the first section of the material may be deposited simultaneously on two substrates under a set of processing conditions, and the properties of the first section on each substrate may not be matched. The distance of one of the stations may be adjusted, and the simultaneous deposition of the second section of the material may be performed on the two substrates. Different distances of one of the stations may change the second section of the material so that the values of the properties of the first section may be closer. For example, the overall target thickness of the deposited material may be 280 Å on both substrates. After the first deposition, the thicknesses of the first section of the material may be different from each other, for example, 275 Å and 272 Å. By adjusting one of the stations to different distances, the thickness of the material deposited at that station may be changed so that the second section has different thicknesses, but the overall thickness of the first and second sections together may be closer to each other. In this example, the second section of the material at the adjusted station may be 8 Å, and at the other station, the second section of the material may be 5 Å, thereby resulting in a matching material thickness of 280 Å on both substrates after the second deposition.

[0120] Similarly, a fifth example of the technique may include performing simultaneous plasma generation and deposition on a substrate first while the pedestals are at different distances, and then adjusting only one of the pedestals so that only that pedestal is at the same distance as the other pedestal for subsequent simultaneous plasma generation and deposition. Referring to FIG. 9, this may include, in sequential order, adjusting the first pedestal from a first distance to a second distance such that both pedestals are at the same distance, i.e., the second distance, in blocks 901, 903, 905, different adjustment blocks 909, and then performing block 907.

[0121] In a sixth example of the technique, the substrate may be positioned at different distances for one portion of the deposition process and then at other different distances for another portion of the deposition process. FIG. 11 depicts a sixth technique for performing film deposition in a multi-station semiconductor processing chamber. In this case, blocks 1101-1105 are the same as blocks 801-805 described above with respect to FIGS. 8 and 9, as well as blocks 901, 903, and 905. In this case, in FIG. 11, blocks 1101, 1103, and 1105 are performed, and then adjustment block 1109 adjusts the first pedestal to a third distance different from the first distance and adjusts the second pedestal to a fourth distance different from the second distance. After the pedestals are at these other different distances, at block 1107, another simultaneous deposition is performed on two substrates.

[0122] Referring to FIGS. 10B and 10C, block 1105 corresponds to the chamber of FIG. 10B, while block 1107 corresponds to the chamber of FIG. 10C. In FIG. 10C, the first station is at a third distance and the second station is at a fourth distance. The first distance is shorter than the third distance, but in some embodiments this may be reversed such that the first distance is longer than the third distance. This may also be the same for the second and fourth distances.

[0123] In some embodiments, the amount by which each station is adjusted may be different for each station. In some other embodiments, it may be desirable to maintain the pedestals at different distances from each other but adjust the pedestals by the same amount. This may provide uniform control and adjustment of properties to all of the substrates. By way of example, the difference between the first and third distances may be the same as the difference between the second and fourth distances.

[0124] B. Example of a Technique Using Pedestals at the Same Distance As stated explicitly above, in some embodiments the pedestals may remain at the same distance relative to each other, but are positioned at different distances relative to the showerhead during deposition processing. This concept is illustrated in FIG. 12 depicting a seventh example of a technique for performing film deposition in a multi-station semiconductor processing chamber. In this case, blocks 1201 and 1203 are the same as blocks 801 and 803 described above. At block 1205, both the first pedestal and the second pedestal are positioned at the same first distance from their corresponding showerheads, and a first plasma and a second plasma are simultaneously generated at the station to deposit a first layer of material and a second layer of material on the first substrate and the second substrate, respectively. At block 1209, both the first pedestal and the second pedestal are adjusted to the same second distance, and then at block 1207, a third plasma and a fourth plasma are simultaneously generated at the station to deposit a third layer of material and a fourth layer of material on the first substrate and the second substrate, respectively. Referring to FIGS. 10D and 10E, these figures correspond to the seventh example of the technique. FIG. 10D corresponds to block 1205 where the first pedestal 118A and the second pedestal 118B are both at the same first distance. FIG. 10E corresponds to block 1207 where the first pedestal 118A and the second pedestal 118B are both at the same second distance.

[0125] In this case, the pedestals remain at the same distance relative to each other during deposition processing, but are at different distances relative to the showerhead. These embodiments may produce deposited materials with different property values throughout the material. In an example, the material deposited on the first substrate has two different properties within the material, such as two different densities or WERs. The distance may be adjusted several more times to create additional values and gradients within the deposited material.

[0126] In some embodiments, as depicted in FIGS. 10D and 10E, the first distance may be longer than the second distance. Performing some deposition while the pedestal is initially far from the showerhead may be advantageous for some deposition processes. As described above and as seen in FIGS. 4 and 6, plasma power reduction is associated with an increase in the pedestal-showerhead distance, and using this seventh example of the technique, the substrate may initially be exposed to lower power to protect the substrate. After depositing some layers of material on the substrate, the plasma power may be increased by reducing the distance. For example, depositing some silicon oxide on a carbon substrate may cause some carbon consumption or damage during processing. However, when some carbon is exposed at the start of deposition, this consumption and damage can be reduced by positioning the pedestal at a longer distance and exposing the substrate to lower plasma power. Once some deposition has occurred and the carbon is protected and no longer exposed, the plasma power can be increased by reducing the distance.

[0127] C. Use of Examples of Techniques Using Various Deposition Processes As stated above, all of the examples of the technique may be used in various deposition processes such as CVD and ALD. Referring to FIG. 8, for example, the simultaneous plasma generation and deposition of block 805 may be all CVD deposition processes for the first substrate and the second substrate.

[0128] For a cyclic deposition process such as ALD, the simultaneous plasma generation and deposition of blocks 805, 905, and 907, and 1105 and 1107 described above may be performed for each cycle of deposition so as to repeat these blocks throughout the deposition process. As stated above, a typical ALD cycle includes (1) exposure of the substrate surface to a first precursor, (2) purging of the reaction chamber in which the substrate is disposed, typically accompanied by plasma and / or a second precursor, activation of the reaction on the substrate surface, and (4) purging of the reaction chamber in which the substrate is disposed. FIG. 13 depicts a flowchart of an example sequence of operations for forming a film of material on a substrate via an ALD process. As can be understood from FIG. 13, item 1 above corresponds to block 1358, item 2 above corresponds to block 1360, item 3 above corresponds to block 1362, item 4 above corresponds to block 1364, the four blocks are performed during N cycles, and then the process stops.

[0129] The simultaneous plasma generation and deposition of the examples of the techniques described herein, such as blocks 805, 905, and 907, and 1105 and 1107, may be considered as the activation step, i.e., 1362 of step 3 of the basic ALD cycle. As stated above, this activation step is performed in each deposition cycle, and each cycle includes a step of igniting the plasma and then extinguishing the plasma. For example, in the first example of the technique of FIG. 8, if the entire deposition process includes N cycles, the simultaneous plasma generation and deposition block 805 may be performed in each of the N cycles.

[0130] In techniques involving multiple simultaneous plasma generation and deposition blocks, such as the example of the technique of FIG. 9, the entire deposition process may be divided into two or more parts, each part having a specific number of deposition cycles, and for the cycles of each part, only one of the simultaneous plasma generation and deposition blocks is performed. In an example, one part may have X cycles and another part may have Y cycles, and one of the simultaneous plasma generation and deposition blocks is performed in each of the X cycles, while the other simultaneous plasma generation and deposition block is performed in each of the Y cycles. Referring to FIG. 9 in the example, block 907 may be performed in each of the X cycles, and block 905 may be performed in each of the Y cycles, so that block 907 is performed X times and block 907 is performed Y times.

[0131] All other examples of the technique may be performed similarly so that each simultaneous plasma generation and deposition block is performed during a specific number of deposition cycles in one part of the entire deposition process. In another example, in the sixth example of the technique of FIG. 11, the entire deposition process may have two parts, the first part having N cycles and the second part having Z cycles. FIG. 14 depicts another example of the technique showing the same sixth example of the technique of FIG. 11. In this case, block 1405 corresponding to block 1105 is performed in each of the N cycles of the first part so as to perform block 1105 N times, and then block 1107 is performed in each of the Z cycles of the second part so as to perform block 907 Z times.

[0132] In some other periodic embodiments, the pedestals may be at different positions throughout each deposition cycle. For example, referring back to FIG. 8, the deposition process may again have N deposition cycles. Each of the N deposition cycles may perform block 805. Additionally, the pedestals may be at different distances in other parts of the deposition process. In an example, the first pedestal and the second pedestal may both be positioned at a third distance during the adsorption step of each cycle and then adjusted to a first distance and a second distance during each activation step. In some other embodiments, the first pedestal and the second pedestal may both be positioned at the same distance for the activation step, i.e., for simultaneous plasma generation and material deposition, and then both be positioned at the same but different distances for another one or more steps of each cycle, such as the adsorption step.

[0133] In all of the examples of the techniques described herein, depending on other processing conditions, the first and second layers deposited, or the materials deposited simultaneously on the substrate, may be the same or different. In an example, the first and second layers deposited, or the materials deposited simultaneously on the substrate, may have the same thickness or different densities. Similarly, in FIGS. 8, 9, and 11, one or more characteristics of the plasma generated at each station may be different from each other. Referring to FIG. 8 in an example, the first plasma and the second plasma generated at different stations may have different plasma powers from each other. However, in some examples, depending on the overall processing conditions, the first plasma and the second plasma generated at different distances may have the same plasma power from each other.

[0134] In some embodiments, the techniques described herein are used in a static mode, such that the substrate remains at the same station for all deposition processes. In some other embodiments, the techniques may be used in other processing modes, such as sequential processing. For example, two or more substrates may be loaded into the chamber and only half of the total deposition may be performed on these substrates. Thereafter, the first two or more substrates are transferred to another station, two or more new substrates are loaded into the chamber, and the other half of the deposition process is simultaneously performed on the first two or more substrates and the two or more new substrates. This completes the deposition on the first two or more substrates and the first half of the deposition on the second two or more substrates. Thereafter, the first two or more substrates are unloaded from the chamber, the second two or more substrates are transferred to another station, and a third set of two or more substrates is loaded. This process may be repeated. During this sequential processing, the stations may be at different distances, as described herein. This may be considered a 2×4 technique.

[0135] Throughout the examples of the techniques described herein, unless otherwise noted, the substrate remains in a fixed position on the corresponding pedestal until it is unloaded and is not moved with respect to the pedestal except during loading and unloading onto the pedestal.

[0136] D. Additional Techniques for Calibration In some embodiments, a calibration deposition process may be performed to determine a showerhead-to-pedestal distance and relate that distance to property values of different materials. The calibration deposition process may include positioning a first set of substrates at a station, positioning the pedestal at a first distance, and simultaneously generating, at the station, a plasma to deposit a material on the first set of substrates, and determining values of properties of the resulting material, such as thickness, WER, DER, and density, by measurement or the like. Next, a second set of substrates may be loaded onto the pedestal, the pedestal may be set at a second distance, and the deposition process may be repeated for the second set of substrates, in which case values of properties of the resulting material may also be determined. This deposition and determination may be performed for N sets of substrates at N different distances. The values of the properties of the material determined for each station are associated with the distance at which deposition was performed at that station, and this information can be used with any of the above techniques to adjust the pedestal distance to deposit a known value of the property of the material.

[0137] For example, referring back to FIG. 4, this may be considered data obtained from a calibration deposition process. In this case, deposition was performed on four sets of substrates at different distances for each set, and the average material thickness obtained after each deposition was measured. Thus, this determined data can be used later to adjust the distance of each pedestal to create a known thickness at that station. As described above, the pedestal of station 1 can be adjusted to a distance of 0.45 inches (11.4 mm) to match the thickness of station 3 at a distance of 0.35 inches (8.89 mm). Similarly, FIG. 5 may provide calibration data regarding WER that can be used in later processing to adjust the WER value at a particular station at different distances. To reduce non-uniformity between stations, after calibration data collection, adjustments tailored to the process can be used.

[0138] In another example, the multi-station processing chamber may be subject to inspection or maintenance, after which the first set of substrates is loaded into the chamber, deposition is performed, and material properties such as thickness are measured. If there is non-uniformity between the substrates, the distance of one or more pedestals can be adjusted to reduce this non-uniformity. In FIG. 4, if the thickness measured for station 3 is 299 Å while the other three stations are about 296 Å, the distance of station 3 can be adjusted to 0.35 inches (8.89 mm) to create a deposition thickness of about 296 Å, as indicated by the correlation in the calibration data of FIG. 4.

[0139] IV. Additional Equipment The techniques and apparatus described herein are not limited to multi-station chambers having only two stations, but are applicable to any number of stations, such as 3, 4, 6, 8, 10 stations, etc. In some such embodiments, when two or more of the pedestals are at different distances from each other, at least some deposition may be performed, which may also include the step of positioning some of the pedestals at the same distance. FIGS. 15A and 15B depict an example of a sequence of pedestal movements in a second example of a multi-station processing chamber having four processing stations. Each of these four stations is the same as FIGS. 7 and 10A - 10E such that each station has a showerhead, a pedestal, and a substrate on the pedestal. In FIG. 15A, the pedestals in all four stations are at different distances from each other, the first station is at a first distance D1, the second station is at a second distance D2, the third station is at a third distance D3, and the fourth station is at a fourth distance D4. Simultaneous plasma generation and deposition at the four stations while the stations are all at different distances may be performed for all or part of the total deposition process for the four substrates 114A - 114D. In some embodiments, two or more pedestals may be at different distances, while on the other hand, two or more pedestals may be at the same distance. In FIG. 15B, the first station, the second station, and the third station are all at different distances, while on the other hand, the third station and the fourth station are at the same distance D3. Again, simultaneous plasma generation and deposition at the four stations while the stations are at these distances may be performed for all or part of the total deposition process for the four substrates 114A - 114D.

[0140] The adjustment to the distances described above may also be performed on a multi-station processing chamber having three or more stations. For example, similar to the second example of the technique of FIG. 9, all of the three or more stations may be at the same distance for the first part of the overall deposition process, including N deposition cycles, after which the distance is adjusted so that, for another part of the deposition process, such as for X deposition cycles, the three or more stations are at different distances from each other. Additionally, the order of these parts of the deposition process may be reversed such that three or more stations are at different distances to start deposition and then are changed to the same distance in a subsequent deposition process. Further, as in the sixth technique, two or more pedestals may be at different distances from each other for one part of the overall deposition process and then adjusted to other different distances in the second part of the overall deposition process. Referring to FIG. 15A by way of example, four stations may be at four different distances D1 - D4 for the first part of the deposition process and then all adjusted to distances D5 - D8 respectively for the second part of the deposition process.

[0141] In some embodiments, a semiconductor processing tool or apparatus may have a controller with program instructions for performing any or all of the examples of the techniques described herein. By way of example, the apparatus may have the features of the substrate processing apparatus 200 of FIG. 2, including a processing chamber 210 with a number of processing stations (e.g., stations 231 - 234). Additionally, each pedestal within the apparatus is configured to be positioned at various distances, such as being adjusted before, during, and after operation.

[0142] The controller 238 includes controlling the apparatus to execute the techniques described above and may have program instructions to deposit material on a substrate at a station. The program instructions include providing a first substrate on a first pedestal at station 231, providing a second substrate on a second pedestal at station 232, moving the first pedestal such that the first pedestal is separated from the first showerhead by a first distance, moving the second pedestal such that the second pedestal is separated from the second showerhead by a second distance, and simultaneously generating a first plasma at the first station while the first pedestal is separated from the first showerhead by the first distance, thereby depositing a first layer of material on the first substrate, and generating a second plasma at the second station while the first plasma is being generated simultaneously and while the second pedestal is separated from the second showerhead by the second distance, thereby depositing a second layer of material on the second substrate. The controller may also include additional instructions for adjusting the distance of each pedestal, including moving the first pedestal to a third distance, moving the second pedestal to a fourth distance, and then simultaneously generating a third plasma at the first station while the first pedestal is separated from the first showerhead by the third distance, thereby depositing a third layer of material on the first substrate, and generating a fourth plasma at the second station while the third plasma is being generated simultaneously and while the second pedestal is separated from the second showerhead by the fourth distance, thereby depositing a fourth layer of material on the second substrate.

[0143] The foregoing disclosure has focused on adjusting the pedestal position to control deposition parameters, but the same control may be used to control etching characteristics in an etching process. Some semiconductor fabrication processes involve patterning and etching various materials including conductors, semiconductors, and dielectrics. Some examples include conductors such as metal or carbon, semiconductors such as silicon or germanium, and dielectrics such as silicon oxide, aluminum oxide, zirconium dioxide, hafnium dioxide, silicon nitride, and titanium nitride. Atomic layer etching (“ALE”) processes use sequential self-limiting reactions to remove thin layers of material. Generally, an ALE cycle is the minimum set of operations used to perform an etching process such as etching a monolayer at one time. The result of one ALE cycle is to etch at least a portion of a film layer on a substrate surface. Typically, an ALE cycle includes a modification operation to form a reaction layer, followed by a removal operation to remove or etch only this reaction layer. The cycle may include certain auxiliary operations such as removing one of the reactants or by-products. Generally, one cycle encompasses one instance of a particular sequence of operations.

[0144] As an example, a conventional ALE cycle may include operations of (i) delivering reactant gas, (ii) purging the reactant gas from the chamber, (iii) delivering removal gas and optional plasma, and (iv) purging the chamber. In some embodiments, etching may be performed anisotropically. The modification operation generally forms a less reactive surface layer that is thinner in thickness than the unmodified material. In an example of the modification operation, the substrate may be chlorinated by introducing chlorine into the chamber. Chlorine is used as an example of an etchant species or etching gas, but it will be understood that different etching gases may be introduced into the chamber. The etching gas may be selected according to the type and chemical properties of the substrate to be etched. Plasma may be ignited, and for the etching process, chlorine may react with the substrate, i.e., chlorine may react with the substrate or may be adsorbed on the surface of the substrate. The species generated from the chlorine plasma can be generated directly by forming plasma in the processing chamber containing the substrate, or can be generated remotely in a processing chamber not containing the substrate and supplied into the processing chamber containing the substrate.

[0145] Accordingly, any of the above techniques and apparatuses may be used for etching. In some embodiments, instead of depositing a layer of material at each station, the technique may remove a portion of the material at each station. This may result in greater wafer-to-wafer non-uniformity in the etching process or deposition process. For example, in FIG. 8, operation 805 may be an etching stage, in which, for the first portion of the etching process, a first plasma and a second plasma are simultaneously generated while a first pedestal and a second pedestal are separated by a first distance and a second distance, respectively, to remove a first portion of the material and a second portion of the material from a first substrate and a second substrate, respectively.

[0146] The above has focused on controlling the pedestal distance for plasma-based operations, but all of the above techniques may be applied to other aspects or stages of semiconductor processing, such as while the substrate is being exposed to precursors. This may include during the irradiation stage of an ALD cycle, or during the concurrent plasma and precursor exposure of PECVD, for example. For instance, the techniques described above and shown in FIGS. 8-12, FIG. 14, and FIGS. 15A and 15B relate to plasma generation, but the disclosed techniques are of course extended to exposure to processes where the precursors contact the substrate. In some embodiments, for a first portion of a deposition process, the technique may simultaneously include flowing a precursor over a first substrate at a first station while a first pedestal is separated from a first showerhead of the first station by a first distance, and flowing a precursor over a second substrate at a second station while a second pedestal is separated from a second showerhead of the second station by a second distance different from the first distance.

[0147] In some other embodiments, a deposition process step that includes concurrent plasma generation and exposure to a precursor may, for a first portion of the deposition process, simultaneously (i) generate a first plasma at a first station and concurrently flow a precursor over a first substrate while a first pedestal is separated from a first showerhead of the first station by a first distance, thereby depositing a first layer of material on the first substrate, and (ii) generate a second plasma at a second station and concurrently flow a precursor over a second substrate while a second pedestal is separated from a second showerhead of the second station by a second distance different from the first distance, thereby depositing a second layer of material on the second substrate.

[0148] In addition to the claims recited in this disclosure, it is to be understood that the following additional implementations fall within the scope of this disclosure.

[0149] Embodiment 1: A multi-station deposition apparatus, comprising a processing chamber, a first showerhead, and a first pedestal configured to move vertically with respect to the first showerhead, a first processing station in the processing chamber, a second showerhead, and a second pedestal configured to move vertically with respect to the second showerhead, a second processing station in the processing chamber, and a controller for controlling the multi-station apparatus to deposit material on a substrate at the first station and the second station, the controller providing a first substrate to the first pedestal, providing a second substrate to the second pedestal, moving the first pedestal so that the first pedestal is separated from the first showerhead by a first distance, moving the second pedestal so that the second pedestal is separated from the second showerhead by a second distance, and simultaneously generating a first plasma at the first station while the first pedestal is separated from the first showerhead by the first distance, thereby depositing a first layer of material on the first substrate, and generating a second plasma at the second station while the second pedestal is separated from the second showerhead by a second distance different from the first distance, thereby depositing a second layer of material on the second substrate.

[0150] Embodiment 2: The apparatus according to Embodiment 1, wherein the controller further comprises control logic for moving the first pedestal so that the first pedestal is separated from the first showerhead by a third distance, moving the second pedestal so that the second pedestal is separated from the second showerhead by a fourth distance, and simultaneously generating a third plasma at the first station while the first pedestal is separated from the first showerhead by the third distance, thereby depositing a third layer of material on the first substrate, and generating a fourth plasma at the second station while the second pedestal is separated from the second showerhead by the fourth distance, thereby depositing a fourth layer of material on the second substrate.

[0151] Embodiment 3: The apparatus according to Embodiment 2, wherein the third distance is different from the fourth distance.

[0152] Embodiment 4: An apparatus according to Embodiment 2, wherein the third distance is the same as the fourth distance.

[0153] Embodiment 5: An apparatus according to Embodiment 4, wherein the controller further comprises control logic for simultaneously generating a third plasma at a third station and a fourth plasma at a fourth station before simultaneously generating a first plasma at a first station and a second plasma at a second station.

[0154] Embodiment 6: An apparatus according to Embodiment 4, wherein the controller further comprises control logic for simultaneously generating a third plasma at a third station and a fourth plasma at a fourth station after simultaneously generating a first plasma at a first station and a second plasma at a second station.

[0155] Embodiment 7: An apparatus according to Embodiment 1, wherein the first pedestal may be configured to apply a first chucking force to a first substrate, the second pedestal may be configured to apply a second chucking force to a second substrate, and the controller further includes control logic for causing the first pedestal to apply the first chucking force to the first substrate and the second pedestal to apply the second chucking force to the second substrate during a first portion of the deposition process.

[0156] Embodiment 8: An apparatus according to Embodiment 7, wherein the first chucking force and the second chucking force are electrostatic forces.

[0157] Embodiment 9: An apparatus according to Embodiment 7, wherein the first chucking force and the second chucking are applied by a vacuum.

[0158] Embodiment 10: A multi-station deposition apparatus, the apparatus comprising: a processing chamber; a first processing station within the processing chamber, including a first showerhead and a first pedestal configured to move vertically with respect to the first showerhead; a second processing station within the processing chamber, including a second showerhead and a second pedestal configured to move vertically with respect to the second showerhead; and a controller for controlling the multi-station deposition apparatus to deposit material on substrates at the first station and the second station, the controller providing a first substrate to the first pedestal, providing a second substrate to the second pedestal, moving the first pedestal so that the first pedestal is separated from the first showerhead by a first distance, moving the second pedestal so that the second pedestal is separated from the second showerhead by the first distance, and while the first pedestal is separated from the first showerhead by the first distance, generating a first plasma at the first station, thereby depositing a first layer of material on the first substrate, and while the second pedestal is separated from the second showerhead by the first distance, generating a second plasma at the second station, thereby depositing a second layer of material on the second substrate, after generating the first plasma and the second plasma simultaneously, moving the first pedestal so that the first pedestal is separated from the first showerhead by a second distance, after depositing the first plasma and the second plasma simultaneously, moving the second pedestal so that the second pedestal is separated from the first showerhead by the second distance, and while the first pedestal is separated from the first showerhead by the second distance, generating a third plasma at the first station, thereby depositing a third layer of material on the first substrate, and while the second pedestal is separated from the second showerhead by the second distance, generating a fourth plasma at the second station, thereby depositing a fourth layer of material on the second substrate, the multi-station deposition apparatus comprising control logic for this purpose.

[0159] Embodiment 11: The apparatus of Embodiment 10, wherein the first distance is longer than the second distance.

[0160] Embodiment 12: A multi-station deposition apparatus, the apparatus comprising: a processing chamber; a first processing station in the processing chamber, including a first shower head and a first pedestal configured to move vertically with respect to the first shower head; and a second station in the processing chamber, including a second shower head and a second pedestal configured to move vertically with respect to the second shower head, wherein the first pedestal is separated from the first shower head by a first distance, and the second pedestal is separated from the second shower head by a second distance different from the first distance.

[0161] Embodiment 13: The apparatus according to Embodiment 12, further comprising a third processing station in the processing chamber, including a third shower head and a third pedestal configured to move vertically with respect to the third shower head, wherein the third pedestal is separated from the third shower head by a third distance equal to the first distance.

[0162] Embodiment 14: The apparatus according to Embodiment 13, further comprising a fourth processing station in the processing chamber, including a fourth shower head and a fourth pedestal configured to move vertically with respect to the fourth shower head, wherein the fourth pedestal is separated from the fourth shower head by a fourth distance different from the first distance, the second distance, and the third distance.

[0163] Embodiment 15: The apparatus according to Embodiment 13, further comprising a fourth processing station in the processing chamber, including a fourth shower head and a fourth pedestal configured to move vertically with respect to the fourth shower head, wherein the fourth pedestal is separated from the fourth shower head by a fourth distance equal to the first distance or the second distance.

[0164] Embodiment 16: The apparatus of Embodiment 12, further comprising a third processing station in the processing chamber, including a third shower head and a third pedestal configured to move vertically with respect to the third shower head, wherein the third pedestal is separated from the third shower head by a third distance different from the first distance and the second distance.

[0165] Embodiment 17: The apparatus of Embodiment 16, further comprising a fourth processing station in the processing chamber, including a fourth shower head and a fourth pedestal configured to move vertically with respect to the fourth shower head, wherein the fourth pedestal is separated from the fourth shower head by a fourth distance different from the first distance, the second distance, and the third distance.

[0166] Embodiment 18: The apparatus of Embodiment 16, further comprising a fourth processing station in the processing chamber, including a fourth shower head and a fourth pedestal configured to move vertically with respect to the fourth shower head, wherein the fourth pedestal is separated from the fourth shower head by a fourth distance the same as the first distance, the second distance, or the third distance.

[0167] Embodiment 19: A method of depositing a material on a substrate in a multi-station deposition apparatus having a first station and a second station, the method comprising: providing a first substrate on a first pedestal of the first station; providing a second substrate on a second pedestal of the second station; and, for a first portion of the deposition process, simultaneously flowing a precursor over the first substrate at the first station while the first pedestal is separated from the first shower head of the first station by a first distance, and flowing a precursor over the second substrate at the second station while the second pedestal is separated from the second shower head of the second station by a second distance different from the first distance.

[0168] Embodiment 20: The method of Embodiment 19, wherein, simultaneously, for the second part of the deposition process, while the first pedestal is separated from the first showerhead by a third distance, a precursor is flowed onto the first substrate at the first station, and while the second pedestal is separated from the second showerhead by a fourth distance different from the second distance, a precursor is flowed onto the second substrate at the second station.

[0169] Embodiment 21: The method of Embodiment 19, wherein the first part includes N deposition cycles, and each of the N deposition cycles includes, simultaneously, flowing a precursor onto the first substrate at the first station while the first pedestal is separated by a first distance, and flowing a precursor onto the second substrate at the second station while the second pedestal is separated by a second distance.

[0170] Embodiment 22: The method of Embodiment 21, wherein, for the second part of the deposition process including P deposition cycles, in each of the P deposition cycles simultaneously, while the first pedestal is separated from the first showerhead by a third distance, a precursor is flowed onto the first substrate at the first station, and while the second pedestal is separated from the second showerhead by a fourth distance, a precursor is flowed onto the second substrate at the second station.

[0171] Embodiment 23: The method of Embodiment 21, wherein, for the second part of the deposition process including X deposition cycles after the first part, in each of the X deposition cycles simultaneously, while the first pedestal is separated from the first showerhead by a third distance, a precursor is flowed onto the first substrate at the first station, and while the second pedestal is separated from the second showerhead by a third distance, a precursor is flowed onto the second substrate at the second station.

[0172] Embodiment 24: A method according to Embodiment 21, further comprising, for a second part of the deposition process including a deposition cycle of Y, before the first part, flowing a precursor material onto the first substrate at the first station while the first pedestal is separated from the first showerhead by a third distance during each of the deposition cycles of Y, and flowing a precursor material onto the second substrate at the second station while the second pedestal is separated from the second showerhead by a third distance.

[0173] Embodiment 25: A method of depositing a material on a substrate in a multi-station deposition apparatus having a first station and a second station, the method comprising providing a first substrate on a first pedestal of the first station, providing a second substrate on a second pedestal of the second station, for a first part of the deposition process, simultaneously flowing a precursor material onto the first substrate at the first station while the first pedestal is separated from the first showerhead of the first station by a first distance, and flowing a precursor material onto the second substrate at the second station while the second pedestal is separated from the second showerhead of the second station by a first distance, after the first part, adjusting the first pedestal to a second distance and the second pedestal to the second distance, and for a second part of the deposition process, simultaneously flowing a precursor material onto the first substrate at the first station while the first pedestal is separated by the second distance, and flowing a precursor material onto the second substrate at the second station while the second pedestal is separated by the second distance.

[0174] Embodiment 26: A method of depositing a material on a substrate in a multi-station deposition apparatus having a first station and a second station, the method comprising: providing a first substrate on a first pedestal of the first station; providing a second substrate on a second pedestal of the second station; for a first portion of the deposition process, simultaneously generating a first plasma at the first station while the first pedestal is separated from a first showerhead of the first station by a first distance, flowing a precursor simultaneously over the first substrate, thereby depositing a first layer of material on the first substrate, and generating a second plasma at the second station while the second pedestal is separated from a second showerhead of the second station by a second distance different from the first distance, flowing a precursor simultaneously over the second substrate, thereby depositing a second layer of material on the second substrate.

[0175] In the following description, numerous specific details are set forth in order to provide a thorough understanding of the presented concepts. The presented concepts may be practiced without some or all of these specific details. In other instances, well-known processing operations have not been described in detail in order not to obscure the concepts being described needlessly. Although some concepts are described in connection with specific embodiments, it will be understood that these embodiments are not intended to be limiting.

[0176] Unless the content of the present disclosure clearly requires otherwise, throughout this specification and the claims, terms such as "comprise", "comprising", etc. shall be construed in an inclusive sense as opposed to an exclusive or exhaustive sense, that is, in the sense of "including but not limited to". Words using the singular or plural generally also include the plural or singular respectively. Additionally, words such as "herein", "under this specification", "above", "below" and words of similar meaning refer to the entire application as a whole and not to any particular layer of the application. When using the word "or" with reference to a list of two or more items, the word shall cover the following interpretations for the word, namely, any of the items in the list, all of the items in the list, and all of any combination of the items in the list. The term "implementation" refers not only to the implementation of the techniques and methods described herein, but also to the physical objects that embody the structure and / or incorporate the techniques and / or methods described herein. In this specification, the term "substantially" means within a range of 5% of the reference value unless otherwise specified. For example, substantially vertical means parallel within a range of ±5%.

Claims

1. A method of depositing a material on a substrate in a multi-station deposition apparatus having a first station and a second station, comprising: providing a first substrate on a first pedestal of the first station; providing a second substrate on a second pedestal of the second station; for a first portion of a deposition process, simultaneously: generating a first plasma at the first station while the first pedestal is separated from a first showerhead of the first station by a first distance, thereby depositing a first layer of the material on the first substrate; generating a second plasma at the second station while the second pedestal is separated from a second showerhead of the second station by a second distance different from the first distance, thereby depositing a second layer of the material on the second substrate; and a method comprising the steps.

2. The method according to claim 1, wherein for a second portion of the deposition process, simultaneously: generating a third plasma at the first station while the first pedestal is separated from the first showerhead by a third distance different from the first distance, thereby depositing a third layer of the material on the first substrate; generating a fourth plasma at the second station while the second pedestal is separated from the second showerhead by a fourth distance different from the second distance, thereby depositing a fourth layer of the material on the second substrate; and further comprising the steps.

3. The method according to claim 2, wherein the difference between the first distance and the third distance is substantially the same as the difference between the second distance and the fourth distance.

4. The method according to claim 1, wherein for a second layer of the deposition process, simultaneously: generating a third plasma at the first station while the first pedestal is separated from the first showerhead by a third distance, thereby depositing a third layer of the material on the first substrate; generating a fourth plasma at the second station while the second pedestal is separated from the second showerhead by the third distance, thereby depositing a fourth layer of the material on the second substrate; and further comprising the steps.

5. The method according to claim 1, wherein The first part includes a deposition cycle of N, Each of the deposition cycles of N simultaneously generating the first plasma at the first station while the first pedestal is separated by the first distance, thereby depositing the first layer of the material on the first substrate, and generating the second plasma at the second station while the second pedestal is separated by the second distance, thereby depositing the second layer of the material on the second substrate; igniting and extinguishing the first plasma and the second plasma A method comprising. **Claim 6** The method according to claim 5, For a second part of the deposition process including a deposition cycle of X after the first part, in each of the deposition cycles of X, simultaneously, generating a third plasma at the first station while the first pedestal is separated from the first shower head by a third distance, thereby depositing a third layer of the material on the first substrate, generating a fourth plasma at the second station while the second pedestal is separated from the second shower head by the third distance, thereby depositing a fourth layer of the material on the second substrate, and each of the deposition cycles of X includes igniting and extinguishing the third plasma and the fourth plasma A method further comprising the step of. **Claim 7** The method according to claim 5, For a second part of the deposition process including a deposition cycle of Y before the first part, in each of the deposition cycles of Y, simultaneously, generating a third plasma at the first station while the first pedestal is separated from the first shower head by a third distance, thereby depositing a third layer of the material on the first substrate, generating a fourth plasma at the second station while the second pedestal is separated from the second shower head by the third distance, thereby depositing a fourth layer of the material on the second substrate, and each of the deposition cycles of Y includes igniting and extinguishing the third plasma and the fourth plasma A method further comprising the step of. **Claim 8** The method according to claim 5, adjusting the first pedestal between the first distance and the third distance Adjusting the second pedestal between the second distance and the fourth distance; For a second portion of the deposition process including a deposition cycle of Z, in each of the deposition cycles of Z, simultaneously, Generating a third plasma at the first station while the first pedestal is separated from the first showerhead by the third distance, thereby depositing a third layer of the material on the first substrate; Generating a fourth plasma at the second station while the second pedestal is separated from the second showerhead by the fourth distance, thereby depositing a fourth layer of the material on the second substrate, wherein each of the deposition cycles of Z includes igniting and extinguishing the third plasma and the fourth plasma; A method further comprising the step.

9. The method according to claim 5, wherein each of the deposition cycles of N at the first station and the second station comprises: (i) Adsorbing a film precursor on the substrate at the station such that the precursor forms an adsorption-limiting layer on the substrate; (ii) Removing at least a portion of the unadsorbed film precursor from the volume surrounding the adsorbed precursor; (iii) Reacting the adsorbed film precursor by generating a plasma at the station after removing the unadsorbed precursor in (ii) to form a layer of the material on the substrate at the station; (iv) Removing the desorbed film precursor and / or reaction by-products, if present after reacting the adsorbed precursor, from the volume surrounding the film layer. A method comprising.

10. The method according to claim 9, comprising: Adjusting the first pedestal from the first distance to the third distance; Adjusting the second pedestal from the second distance to the fourth distance; Further comprising, For (iii) of each cycle, the first pedestal is at the first distance and the second pedestal is at the second distance; For one or more of (i), (ii), or (iv) of each cycle, the first pedestal is at the third distance and the second pedestal is at the fourth distance.

11. The method according to claim 1, further comprising the step of providing a third substrate on a third pedestal of a third station in the multi-station deposition apparatus, wherein the first part of the deposition process further comprises, simultaneously, generating a third plasma at the third station while the third pedestal is separated from a third showerhead of the third station by a third distance, thereby depositing a third layer of the material on the third substrate, wherein the third distance is different from the first distance and the second distance. **Claim 12** The method according to claim 11, for the second part of the deposition process, simultaneously, generating a fourth plasma at the first station while the first pedestal is separated from the first showerhead by a fourth distance, thereby depositing a fourth layer of the material on the first substrate, generating a fifth plasma at the second station while the second pedestal is separated from the second showerhead by the fourth distance, thereby depositing a fifth layer of the material on the second substrate, generating a sixth plasma at the third station while the fourth plasma and the fifth plasma are being generated simultaneously and while the third pedestal is separated from the third showerhead by the fourth distance, thereby depositing a sixth layer of the material on the third substrate step The method further comprising. **Claim 13** The method according to claim 1, wherein the first plasma has plasma characteristics of a first value, wherein the second plasma has plasma characteristics of a second value different from the first value. **Claim 14** The method according to claim 13, wherein the plasma characteristics comprise plasma power. **Claim 15** The method according to claim 1, wherein the first layer of the material on the first substrate has properties of a first value, wherein the second layer of the material on the second substrate has properties of a second value substantially the same as the first value. **Claim 16** The method according to claim 1, wherein the first layer of the material on the first substrate has properties of a first value, wherein the second layer of the material on the second substrate has properties of a second value different from the first value. **Claim 17** The method according to claim 15, wherein the property is selected from the group consisting of wet etching rate, dry etching rate, composition, thickness, density, amount of crosslinking, chemical properties, reaction completion, stress, refractive index, dielectric constant, hardness, etching selectivity, stability, and hermeticity.

18. The method according to claim 1, wherein the first layer of the material on the first substrate has a property of a first value, the second layer of the material on the second substrate has the property of the first value.

19. The method according to claim 1, wherein before providing the first substrate and the second substrate, providing a third substrate on the first pedestal; before providing the first substrate and the second substrate, providing a fourth substrate on the second pedestal; for a second deposition process, simultaneously, generating a third plasma at the first station while the first pedestal is separated from the first shower head by a third distance, thereby depositing a third layer of the material on the third substrate; generating a fourth plasma at the second station while the second pedestal is separated from the second shower head by the first distance, thereby depositing a fourth layer of the material on the fourth substrate, wherein a first non-uniformity between the property of the first layer of the material on the first substrate and the property of the second layer of the material on the second substrate is smaller than a second non-uniformity between the property of the third layer of the material on the third substrate and the property of the fourth layer of the material on the fourth substrate step and a method further comprising.

20. The method according to claim 1, wherein the first pedestal applies a chucking force to the first substrate during the first part of the deposition process, the second pedestal applies a chucking force to the second substrate during the first part of the deposition process.

21. A method of depositing a material on a substrate in a multi-station deposition apparatus having a first station and a second station, comprising: providing a first substrate on a first pedestal of the first station; providing a second substrate on a second pedestal of the second station; for a first part of a deposition process, simultaneously, While the first pedestal is separated from the first showerhead of the first station by a first distance, generate a first plasma at the first station, thereby depositing a first layer of the material on the first substrate. While the second pedestal is separated from the second showerhead of the second station by the first distance, generate a second plasma at the second station, thereby depositing a second layer of the material on the second substrate; After the first portion, adjusting the first pedestal to a second distance and the second pedestal to the second distance; For a second portion of the deposition process, simultaneously, While the first pedestal is separated by the second distance, generate a third plasma at the first station, thereby depositing a third layer of the material on the first substrate; While the second pedestal is separated by the second distance, generate a fourth plasma at the second station, thereby depositing a fourth layer of the material on the second substrate step A method comprising.

22. The method according to claim 21, wherein The first layer of the material on the first substrate has a property of a first value; The second layer of the material on the second substrate has the property of a second value; The third layer of the material on the first substrate has the property of a third value different from the first value; The second layer of the material on the second substrate has the property of a fourth value different from the second value.

23. The method according to claim 21, wherein the first distance is longer than the second distance.

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