Showerhead device for semiconductor processing system

Abstract

To provide a showerhead device which enables control of the conformality and uniformity of an etch process.SOLUTION: In a semiconductor processing apparatus 1, in order to create constant partial pressures of by-products and residence time of gas molecules across a wafer, a reactant gas (e.g., an etch gas) enters into a dual showerhead device 10 at a gas inlet 16 and into an upper plenum 24, and flows towards a susceptor plate 5 holding the wafer 6. Gas outlet apertures 20 of the dual showerhead remove vapors from a chamber 3 through a pump 9 connected to an internal or lower showerhead plenum 22. A second gas outlet line 26 can also be utilized to remove vapors through the pump 9.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to U.S. Provisional Patent Application No. 62 / 875,909, filed July 18, 2019, the contents of which are incorporated herein by reference in their entirety for all purposes.

[0002] background The present invention relates generally to showerhead devices for semiconductor processing systems. [Background technology]

[0003] Vapor deposition processes such as atomic layer deposition (ALD) are well known. ALD processes typically utilize alternating and sequential delivery of gas-phase reactants to a substrate in a controlled and highly conformal manner to deposit a layer of material. Here, efficient removal of reactants between pulses is important to minimize undesired reactions in the gas phase. Thin films deposited by ALD are used in a wide range of applications, such as the formation of integrated circuits. Controlled removal of material is also highly desirable. Exemplary processes for controllably removing material to define circuits and other structures are chemical vapor etching (CVE) or atomic layer etching (ALE). Some CVE processes employ a pulsed delivery of etchant. For example, in some etching processes, sequential pulses of gas-phase reactants can remove small amounts of material from a substrate in a controlled and / or selective manner. Summary of the Invention

[0004] According to one embodiment, a semiconductor processing apparatus is disclosed. The apparatus can include a reaction chamber and a first exhaust port configured to remove vapor from the reaction chamber. The apparatus can also include a showerhead device connected to the reaction chamber and configured to deliver reactant vapor to the reaction chamber. The showerhead device can include a gas inlet configured to supply reactant vapor into the showerhead device, a first showerhead plate in fluid communication with the gas inlet, the first showerhead plate including a plurality of openings, a plurality of inlet ports in fluid communication with the plurality of openings, the plurality of inlet ports configured to deliver reactant vapor to the reaction chamber, and a second showerhead plate including a plurality of second exhaust ports configured to remove vapor from the reaction chamber. The apparatus can also include one or more pumps connected to the first exhaust port and the plurality of second exhaust ports, the one or more pumps configured to remove vapor from the reaction chamber through the first exhaust port and the plurality of second exhaust ports.

[0005] According to one aspect, a semiconductor processing apparatus is disclosed. The apparatus can include a reaction chamber, a reaction chamber exhaust port configured to remove vapor from the reaction chamber, and a showerhead device including a plurality of distributed inlet openings in fluid communication with a reaction vapor source and the reaction chamber, and a plurality of distributed exhaust openings in fluid communication with a pump and the reaction chamber.

[0006] According to one aspect, a method of etching a substrate is disclosed that includes providing a reactant vapor into a showerhead device, conveying the reactant vapor to a reaction chamber through a plurality of distributed inlet openings in the showerhead device, removing the vapor from the reaction chamber through a first exhaust port exposed to the reaction chamber, and removing the vapor from the reaction chamber through a plurality of second exhaust ports in the showerhead device.

[0007] These and other features, aspects, and advantages of the present invention will now be described with reference to drawings of several embodiments that are intended to illustrate, not limit, the invention. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 illustrates a schematic side view of a reactor having a dual showerhead device according to some embodiments. [Figure 2] FIG. 2 illustrates a side cross-sectional view of a dual showerhead device according to some embodiments. [Figure 3A] FIG. 3A illustrates a gas inlet for a showerhead device according to some embodiments. [Figure 3B] FIG. 3B illustrates a schematic three-dimensional perspective view of the gas inlet of FIG. 3A. [Figure 3C] FIG. 3C illustrates the gas inlet of FIG. 3A including an insert. [Figure 4] FIG. 4 illustrates a schematic side cross-sectional view of a portion of a dual showerhead device according to some embodiments. [Figure 5] FIG. 5 illustrates a top plan view of a second showerhead plate of the lower portion of the showerhead device of FIG. 4, according to some embodiments. [Figure 6] FIG. 6 illustrates a top plan view of a second showerhead plate according to some embodiments. [Figure 7] FIG. 7 illustrates a reactor with a dual showerhead and a movable susceptor according to some embodiments. DETAILED DESCRIPTION OF THE INVENTION

[0009] Chemical etching of microelectronic materials may have advantages over plasma etching. However, to provide uniform etching rates across the wafer, the partial pressures, residence times, and temperatures of etching reactants (such as adsorbed reactants and / or etchants) and byproducts should not vary significantly spatially above the substrate (such as a wafer). While showerhead-type reactors can provide uniform distribution of the partial pressures of the inlet gases, the partial pressures of the byproducts and the residence times of the gas molecules may not be constant across the wafer. For example, because pumping to evacuate the reaction chamber is typically performed from the periphery of the wafer, molecules entering from the center of the showerhead have a longer residence time in the reactor compared to molecules entering from the edge of the wafer.

[0010] Various embodiments disclosed herein can be used in etching processes (e.g., CVE processes). Any suitable etching chemistry can be used in the disclosed embodiments. As an example, the process can include one or more etching cycles, where each cycle exposes the substrate to a first gas-phase halide reactant having a first halide ligand to form adsorbed species on the substrate surface, and then exposes the substrate to a second gas-phase halide reactant having a second halide ligand to convert the adsorbed species to volatile species, thereby removing at least some material from the film. In various embodiments, the film can include W, TiN, TiO, TaN, SiN, AlO, AlO, ZrO, WO, SiOCN, SiOC, SiCN, AlN, or HfO. The first gas-phase halide can be a metal halide (such as Nb, Ta, Mo, Sn, V, Re, Te, W, and Group 5 and 6 transition metals). The second gas phase halide can be a carbon-based halide (such as CCl or CBr). Further examples of various etching chemistries and processes that can be used in conjunction with the disclosed embodiments can be found throughout International Patent Application No. PCT / US2017 / 065170, which is incorporated herein by reference in its entirety.

[0011] A dual showerhead reactor can be used to create a constant partial pressure of by-products and a uniform residence time of gas molecules across the substrate. The dual showerhead configuration can achieve spatially uniform partial pressure, residence time, and temperature for both the etch reactants and by-products, thus resulting in a uniform etch rate across the wafer. This device can be used in either a steady-state partial pressure mode, a partial pressure pulse mode, or a total pressure pulse mode, or a combination thereof, depending on which mode is preferred to achieve the desired etch conformality to the substrate.

[0012] Additionally, this device can be integrated with differential pumping to the reactor. It is possible to tailor the residence time distribution and partial pressure profile within the reactor, and thus the etching profile of the substrate (e.g., wafer) by adjusting the pumping speed and conductance of the showerhead device and reaction chamber. For example, the device can be used in a steady-state mode (e.g., constant etching reactant (e.g., etchant) flow), a partial pressure pulse mode (e.g., pulsating the etchant flow while holding the total pressure constant), a pressure pulse mode (e.g., constant etchant flow, pulsating the total pressure), or a total pulse mode (e.g., pulsating the partial and total pressure), or a combination thereof. The pulse mode and pumping mode may determine the partial pressure and residence time distribution of the etchant gas above the wafer under dynamic flow conditions, thereby controlling the conformality and uniformity of the etching process.

[0013] In various embodiments, the etch conformality of the etching process used in conjunction with the disclosed embodiments can be greater than 50%, greater than 80%, greater than 90%, greater than 95%, greater than 98%, or greater than 99%. In some embodiments, the etch selectivity can also be controlled. The etch selectivity can be expressed as a percentage and calculated by [(etched material on surface A) - (etched material on surface B)] / (etched material on surface A). The amount of etching can be measured in various ways. For example, the amount of etching can be expressed as a measured reduced thickness of the etched material, or as a measured amount of etched material based on a comparison of what was originally present to what remains after the etching process. In some embodiments, the selectivity for the etching process is greater than about 10%, greater than about 50%, greater than about 75%, greater than about 85%, greater than about 90%, greater than about 93%, greater than about 95%, greater than about 98%, greater than about 99%, or greater than about 99.5%. In some embodiments, the aspect ratio of the etched features can be greater than about 2:1, 3:1, 5:1, 10:1, 20:1, 40:1, or 100:1.

[0014] For example, the first, upper chamber of the showerhead device can have continuous flow and the second, bottom reaction chamber can have continuous pumping with percolation of reaction byproducts and precursors to reduce pressure spikes. The bottom reaction chamber can provide a constant partial pressure during precursor exposure.

[0015] FIG. 1 illustrates a semiconductor processing apparatus 1 including a reactor 2 with a dual showerhead device 10. The reactor 2 includes a reaction chamber 3 having an interior portion 4 between a susceptor 5 and the showerhead device 10. A susceptor plate 5 resides within the reactor 2 and is attached to the chamber 3. The susceptor plate 5 extends upward from the base of the chamber 3. The susceptor plate 5 supports a substrate 6 (e.g., a wafer) during processing. The dual showerhead device 10 can be positioned above the susceptor 5 and the substrate 6. Although not shown, a gas manifold can supply reactants and inert gases to the showerhead device 10, which can distribute the supplied gases to etch material across the width of the substrate 6. The inlet manifold 11 can be fluidly connected to a reactant source, such as a source of etching reactants (e.g., etchant or adsorption reactant) (see, for example, FIG. 2). The etchant source may be a gas cylinder and / or may include a vaporization device for vaporizing etchant chemicals that are liquid or solid in nature.

[0016] In some embodiments, the dual showerhead 10 can include multiple gas inlets 18 (orifices) and multiple gas outlets 20 (orifices) or exhaust ports. The inlet and outlet openings 18 and 20 do not need to be in direct communication with each other, but can both be in direct fluid communication with the reaction chamber 3 below them. In some embodiments, a second gas outlet line 26 or exhaust port can provide direct fluid communication with the reaction chamber 3 for removing gases from the reaction chamber 3. As demonstrated in FIG. 1 , reactant gases (e.g., etching gases) can enter the dual showerhead device 10 at the gas inlets 16, enter the upper plenum 24, and flow toward the susceptor plate 5 holding the wafer 6. The gas outlet openings 20 of the dual showerhead 10 remove vapor from the chamber 3 through a pump 9 connected to an internal or lower showerhead plenum 22. The second gas outlet line 26 can also be utilized to remove vapor through the pump 9. In some embodiments, the same pump 9 can be used with both gas outlet lines 20, 26. In other embodiments, both gas outlets 20, 26 have separate pumps 9 connected to each of the gas outlet lines 20, 26. In some embodiments, a valve 38 is connected to each gas outlet line 20, 26 and operates in series with the pumps 9 to control the flow of gas out of the reactor chamber 3.

[0017] Thus, in the embodiment of FIG. 1 , semiconductor processing apparatus 1 can include a reaction chamber 3 and a reaction chamber exhaust port 7 configured to remove vapor from reaction chamber 3. Showerhead device 10 can include a plurality of distributed inlet openings 18 in fluid communication with a reactant vapor source and reaction chamber 3. Showerhead device 10 can include a plurality of distributed exhaust openings 20 in fluid communication with a pump 9 and reaction chamber 3. The same pump 9 or different pumps 9 can be connected to showerhead 10 and reaction chamber 3. In the illustrated embodiment, an internal plenum 22 (e.g., defined between two plates) in a lower portion 14 of showerhead 10 can be in communication with pump 9. Inlet opening 18 extends through showerhead device 10 and can, in some embodiments, bypass internal plenum 22. Inlet opening 18 can be in communication with an upper plenum 24 above lower portion 14 of showerhead 10. FIG. 1 shows a simple side gas inlet 16 in communication with upper plenum 24. However, as will be better understood from the description of FIGS. 2-3C below, upper plenum 24 may instead communicate with an inlet manifold that distributes reactant vapors throughout upper plenum 24 .

[0018] One or more pumps 9 can draw residual gases from the exhaust port 20 of the showerhead device 10 and from the exhaust port 7 of the reaction chamber 3. In some embodiments, the pumping speed of gases through the exhaust port 7 of the reaction chamber 3 in the showerhead device 10 is about 25 m / s. 3 / hour ~ approx. 5000m 3 The speed of the pump 9 can be varied in the range of 50 m / s. 3 / hour~about 2500m 3 / time, e.g. 100m 3 / hour~about 2000m 3 / hour. In some embodiments, the pumping speed of gas through the exhaust port 7 of the reaction chamber 3 into the reaction chamber 3 is about 25 m / s. 3 / hour ~ approx. 5000m3 / time range, and the pump speed is approximately 50m 3 / hour~about 2500m 3 / hour, for example, about 100m 3 / hour~about 2000m 3 / hour. In various embodiments, the pump speed (or valve 38 in communication with the common pump 9) can be adjusted to draw different flow rates of exhaust gas from the exhaust ports 7 of the showerhead device 10 and the reaction chamber 3. In some embodiments, the ratio of the pumping rate of gas through the exhaust port 20 in the showerhead device 10 to the pumping rate of gas through the exhaust port 7 of the reaction chamber 3 can be in the range of 100:1 to 1:100, 50:1 to 1:50, 10:1 to 1:10, 5:1 to 1:5, 2:1 to 1:2, or 1.5:1 to 1:1.5. Adjusting the pumping speed can adjust the etching process. Beneficially, the differential pumping systems and techniques disclosed herein and illustrated in FIG. 1 can improve the uniformity and conformality of etching techniques.

[0019] In various embodiments disclosed herein, adjusting the residence time of gaseous or plasma species can be used in plasma etch reactors. Thus, in some embodiments, the apparatus 1 can be used with plasma etch reactors. For example, for RF plasma reactors, a remote plasma can be formed in the showerhead 10 (the upper and lower portions 12 and 14 of the showerhead 10 function as plasma electrodes) or in situ in the reaction chamber 3 (the showerhead device 10 and the susceptor 5 and / or the walls of the reaction chamber 3 function as plasma electrodes), as is known in the art. The embodiments disclosed herein can also be applied to adjusting the plasma itself. In other embodiments, the apparatus 1 disclosed herein can be used in etch reactors that are not plasma etch reactors and / or reactors not used for deposition processes.

[0020] In various embodiments, the showerhead device 10 can be used to provide a throttle valve to adjust the effective pumping speed and / or to regulate the pump 9 to adjust the residence time using an appropriate value of the distance x between the inlet 18 and the outlet opening 20 of the showerhead device 10. In various embodiments, the residence time of a gas molecule can be defined as τ, where τ = v / s, where v is the volume of the reaction space and s is the effective volumetric pumping speed. s can be defined as the total effective pumping speed and can depend on the number of holes in the showerhead device 10 and the distance x between the inlet 18 and the outlet holes 20 of the showerhead device 10. Residence time can describe how long a particular gas species spends inside the reaction space before being pumped out through the exhaust line 26.

[0021] In some reactors 2 (both plasma reactors and thermal etching reactors), the volume of the reaction space may be constant. Various embodiments disclosed herein provide solutions to constant reaction space environments, for example, as shown in FIG. 7. In various embodiments, the residence time can range from 0.1 ms to 10 seconds. For example, the residence time can range from 0.1 ms to 1 ms, 1 ms to 10 ms, 10 ms to 1 s, 1 s to 5 s, 5 s to 10 s, or 5 s to 1 min. The separation distance x can range from a few millimeters to a few centimeters, for example, from 1 mm to 5 cm, or from 1 mm to 1 cm.

[0022] FIG. 2 illustrates a cross-sectional view of a semiconductor processing apparatus 1 including a dual showerhead device 10 for distributing and exhausting gases over a substrate 6, according to various embodiments. In some embodiments, the dual showerhead 10 has an inlet manifold 11 (e.g., a conically shaped top portion) that feeds into an upper portion 12 of the showerhead device 10. The upper portion 12 may include an upper showerhead plate 13 (which may comprise a cylindrical or disc-shaped body) and an upper plenum 24 therebelow. The upper showerhead plate 13 may be disposed above a second, lower portion 14 of the showerhead device 10. In some embodiments, the inlet manifold 11 and the upper showerhead plate 13 may be fabricated separately and then joined by welding both components together. In other embodiments, the inlet manifold 11 and the upper showerhead plate 13 may be joined together using a mechanical joint. In other embodiments, the dual showerhead 10 may be fabricated from a single piece of material. The connections between the components of the showerhead 10 may provide vacuum-type or non-vacuum-type seals. In some embodiments, a space is provided between the upper portion 12 and the lower portion 14 of the showerhead device 10 , which creates an upper showerhead plenum 24 .

[0023] An inlet manifold 11 can be attached near the upper portion 12. The inlet manifold 11 can be connected to a source of reactant vapor, allowing reactant gas from a tank or vaporizer to flow from the inlet manifold 11 into the showerhead device 10. Several channels 42 or branches can be formed in the inlet manifold 11, which can be in fluid communication with one or more gas inlet openings 18, such as by an upper plenum 24. Reactant vapor entering the showerhead device 10 through the inlet manifold 11 can travel through channels 15 defined in the upper showerhead plate 13. In some embodiments, the lower portion 14 of the showerhead device 10 can include both inlet ports 18 (openings) and outlet or exhaust ports 20 (openings). The reactant inlet openings 18 are in fluid communication with the inlet manifold gas channels 42 and gas inlets 16 by the upper plenum 24, thereby allowing gas to flow from the showerhead device 10 and into the reaction chamber 3. In some embodiments, outlet or exhaust openings 20 can draw residual gases into showerhead device 10 through vacuum pressure applied by a vacuum source, such as pump 9. As shown, reaction chamber gas outlet port 7 can draw gases from reaction chamber 3 and can be in fluid communication with one or more pumps 9. Gas outlet line 26 can be connected to one or more pumps 9, which can create a vacuum pressure that draws residual and other gases into exhaust port 20 of showerhead device 10 and into reaction chamber exhaust port 7. The gas inlet 16 and gas outlet 26 structure of showerhead device 10, together with reactant chamber exhaust port 7, can enable reactor 2 to have spatially uniform partial pressures, residence times, and temperatures for the etchant gas and for its by-products.

[0024] 3A-3C illustrate various embodiments of a gas inlet manifold 11 above a showerhead device 10. As seen in FIG. 3A, the gas inlet manifold 11 can have a main line 40. As seen in FIGS. 3A and 3B, gas channels 42 can branch from the main line 40. The gas channels 42 branch off from the main line 40 at multiple points and in multiple directions. The main line 40 can have a slightly conical shape, where the inner diameter d of the main line 40 decreases toward the center of the showerhead. By decreasing the inner diameter d toward the center of the showerhead 10, gas entering the showerhead 10 through the inlet 16 can travel to each channel 42 in a more uniform manner. In some embodiments, as seen in FIG. 3C, an insert 44 is installed in the main line 40, bifurcating the flow path into two. The insert 44 disrupts the flow in the main line 40, forcing gas to flow more uniformly to each branch 42.

[0025] 4 and 5 show that the lower portion 14 of the showerhead device 10 can include two plates 30, 32 that define a lower or internal plenum 22 therebetween. FIG. 5 illustrates the second showerhead plate 32 shown in FIG. 4. In some embodiments, the illustrated lower or internal plenum 22 comprises hollow channels 23 that form several concentric rings on the base of the second showerhead plate 32, while the first showerhead plate 30 can be flat to cover the channels 23. In some embodiments, the inlet openings 18 formed in the second plate 32 are between the channels 23, thus bypassing the internal plenum 22 (or channels) and aligning with the inlet openings 18 in the first plate 30. In the illustrated embodiment, the gas outlet openings 20 are formed through the bottom of the channels 23. The channels 23, or internal plenum 22, connect to the pump 9, as described above. The precursor inlet openings 18, exhaust openings 20, hollow channels 23, and connections 25 to pumps 9 can be arranged in a distributed pattern throughout the lower portion of the showerhead device. For example, the pattern illustrated in FIG. 5 for the reactant inlet openings, exhaust ports, and hollow channels 23 is a circular pattern. One skilled in the art will understand that the illustrated pattern of ports can be an incomplete pattern and the pattern can continue around the entire base of the showerhead plate. In some embodiments, the precursor inlet ports 18, exhaust ports 20, hollow channels 23, and connections 25 to pumps 9 can be arranged in a similar or different pattern to each other. As shown in FIG. 5 , in some embodiments, the lower portion 14 of the showerhead device 10 can have four connections 25 to pumps 9 at 90 degrees to each other. In other embodiments, the lower portion 14 of the showerhead device 10 can have more or fewer than four connections 25 to pumps 9.

[0026] FIG. 6 illustrates a top plan view of a second showerhead plate 32 of the lower portion 14 of the showerhead device 10, according to another embodiment. The second showerhead plate 32 of FIG. 6 can have channels 23 shaped in any suitable manner to define a lower or interior plenum 22. The channels 23 can take several different shapes and patterns. For example, the hollow channels 23 can be arranged in a zigzag pattern or a labyrinth pattern, as shown in FIG. 6. In some embodiments, the second showerhead plate 32 can include multiple channels 23, each having a different or similar pattern. Inlet openings 18 can be formed outside the channels 23, while exhaust openings 20 can be formed in fluid communication with the channels 23, which in turn are connected to one or more pumps 9.

[0027] FIG. 7 illustrates a reactor 2 having a dual showerhead device 10 and a movable susceptor plate 50, as described above. The movable susceptor 50 can create a reactor 2 with a dynamic reaction space. A dynamic reaction space can include adjusting the distance between the movable susceptor plate 50 and the showerhead device 10. For example, the reaction space can be changed whenever desired, every cycle, every half cycle, or periodically. The movable susceptor plate 50 can be adjusted through an external motion driver unit 52. The external motion driver unit 52 can include an analog or digital motor and can be mechanically and electrically connected to the movable susceptor plate 50, allowing the external motion driver unit 52 to adjust the movable susceptor plate 50 (e.g., up and down). The external motion driver unit 52 connected to the apparatus 1 can be used to change the gap between the wafer 6 and the showerhead device 10 (or the top plate in the case of a crossflow reactor) over time, if desired. In some embodiments, the movable susceptor plate 50 can move a distance in a range of 1 mm to 200 mm, a range of 2 mm to 100 mm, a range of 2 mm to 50 mm, or a range of 3 mm to 30 mm. In some embodiments, the susceptor plate can move a distance in a range of 0.1 mm to 50 mm, a range of 0.1 mm to 30 mm, or a range of 0.1 mm to 20 mm. In some embodiments, an external motion driver 52 can rotate the movable susceptor plate 50. In various embodiments, a control system can be in electrical communication with the motor drive, and the control system is configured to adjust the distance between the movable susceptor plate 50 and the showerhead device 10 during etching.

[0028] The control system can also be configured to control the process used in the apparatus 1. In one example of operation utilizing both injection and evacuation through the overhead showerhead device 10, the reactant (e.g., etchant) and evacuation processes can be pulsed or alternated during the process for dynamic pressure control. Therefore, the reactant dose can be divided into multiple short pulses, which can improve the distribution of reactant molecules within the reaction chamber and facilitate rapid gas dispersion by diffusion and / or pressure gradients across the substrate during each reactant or purge pulse. The switch-on and switch-off phases can be repeated at least twice for the reactants. As a result, the pressure in the reaction space rapidly fluctuates between a low pressure level and a higher pressure level. The resulting pressure gradient within the reaction space during the switch-on phase effectively pushes precursor molecules throughout the reaction space, while the resulting pressure gradient within the reaction space during the switch-off phase pulls gaseous reaction byproducts toward the gas outlet and away from the surfaces of the reaction space. When a conventional relatively long pulse (e.g., 1 second) is released into the reaction chamber 3, the pressure can be equalized, thereby eliminating the dynamic dispersion effect, and most of the gas flow tends to go directly toward the gas outlet. When several short pulses (e.g., three times 0.3 seconds each) are released, a much more uniform distribution is achieved within a similar time range.

[0029] The local pressure gradient enhances the exchange of gases within the reaction space and enhances the exchange of molecules between the substrate surface and the gas phase of the reaction space. Multiple identical gas pulses per step, whether a purge step or a reactant step, have been found to be particularly advantageous when processing (e.g., etching) wafers with high aspect ratio features, such as deep, narrow trenches or vias, within a semiconductor substrate. Therefore, the process of multiple consecutive identical vapor pulses and the resulting pressure fluctuations is particularly advantageous for etching surfaces containing vias and trenches with aspect ratios greater than 20:1, and more specifically, vias and trenches with aspect ratios greater than 40:1. The pressure fluctuations allow for more uniform distribution and / or coverage of surfaces within such vias and trenches in a shorter total time than a single long pulse. Therefore, the total process time (or cycle time for cyclical processing) is reduced.

[0030] An example of an etching process will now be described. During precursor A exposure, the gap between the wafer 6 and the showerhead device 10 can be approximately 3 mm and optimized for reactant A delivery. During purge, the gap between the wafer 6 and the showerhead device 10 can be adjusted accordingly. During reactant B exposure, the gap can be adjusted appropriately to deliver reactant B. The disclosed embodiments advantageously provide flexibility for each step of the process. The apparatus described herein can be used in etching processes, including plasma etching processes. For plasma processes, the plasma sheath width, ion bombardment, residence time, plasma density, etc. can be adjusted and optimized for any step of the process.

[0031] While certain specific embodiments have been described, these embodiments are presented by way of example only and are not intended to limit the scope of the present disclosure. Indeed, the novel methods and systems described herein may be embodied in a variety of other forms. Furthermore, various omissions, substitutions, and modifications may be made in the systems and methods described herein without departing from the spirit of the present disclosure. The appended claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the present disclosure. Accordingly, the scope of the present disclosure is defined solely by reference to the appended claims.

[0032] It should be understood that any feature, material, characteristic, or group described in connection with a particular aspect, embodiment, or example is applicable to any other aspect, embodiment, or example described in this section or elsewhere in this specification, unless inconsistent therewith. All features disclosed herein (including any accompanying claims, abstract, and drawings), and / or all steps of any method or process so disclosed, may be combined in any combination, except where at least some of such features and / or steps are mutually exclusive. Protection is not limited to the details of any foregoing embodiment. Protection extends to any novel, or any novel combination, of features disclosed herein (including any accompanying claims, abstract, and drawings), or any novel, or any novel combination of steps of any method or process so disclosed.

[0033] Furthermore, certain features described in this disclosure in the context of separate implementations can also be implemented in combination in a single implementation. Conversely, various features described in the context of a single implementation can also be implemented in multiple implementations separately or in any suitable combination of components. Furthermore, while features may be described above as functioning in a particular combination, one or more features from a claimed combination can, in some cases, be deleted from the combination, and the combination may be claimed as a component of the combination or as a variation of the component of the combination.

[0034] Furthermore, while operations may be depicted in the figures or described in the specification in a particular order, such operations need not be performed in the particular order shown or in the sequential order to achieve desirable results, nor need all operations be performed. Other operations not depicted or described may be incorporated into the example methods and processes. For example, one or more additional operations may be performed before, after, simultaneously with, or between any of the described operations. Furthermore, operations may be rearranged or the order of operations may be changed in other implementations. Those skilled in the art will understand that in some embodiments, the actual steps performed in the illustrated and / or disclosed processes may differ from those shown in the figures. Depending on the embodiment, some of the above-described steps may be omitted, and other steps may be added. Furthermore, the features and attributes of the specific embodiments disclosed above may be combined in different ways to form additional embodiments, all of which are within the scope of the present disclosure. Also, the separation of various system components in the above-described implementations should not be understood as requiring such separation in all implementations. It will also be appreciated that the components and systems described may typically be integrated together in a single product or packaged into multiple products.

[0035] For purposes of this disclosure, certain aspects, advantages, and novel features have been described herein. Not necessarily all such advantages may be achieved in accordance with any particular embodiment. Thus, for example, one skilled in the art will recognize that the present disclosure may be embodied or carried out in a manner that achieves one advantage or group of advantages as taught herein, without necessarily achieving other advantages as may be taught or suggested herein.

[0036] It will be understood that conditional language such as "can," "could," "might," and "may," unless otherwise specified or understood within the context in which it is used, is generally intended to convey that certain embodiments include certain features, elements, and / or steps, while other embodiments do not. Thus, such conditional language is not generally intended to suggest that features, elements, and / or steps are required in more or less ways in one or more embodiments, or that one or more embodiments necessarily include logic for determining whether those features, elements, and / or steps are included in or performed in any particular embodiment, with or without user input or direction.

[0037] Conjunctive language, such as the phrase "at least one of X, Y, and Z," unless specifically stated otherwise, is understood in the context in which it is generally used to convey that an item, term, etc. may be either X, Y, or Z. Thus, such conjunctive language is not generally intended to suggest that a particular embodiment requires the presence of at least one of X, at least one of Y, and at least one of Z.

[0038] As used herein, words of degree, such as "approximately," "about," "generally," and "substantially," refer to a value, amount, or characteristic that is close to the stated value, amount, or characteristic that still performs a desired function or achieves a desired result. For example, the terms "approximately," "about," "generally," and "substantially" can refer to an amount that is within 10%, 5%, 1%, 0.1%, and 0.01% of the stated amount. As another example, in certain embodiments, the terms "generally parallel" and "substantially parallel" refer to a value, amount, or characteristic that deviates from perfect parallelism by 15 degrees or less, 10 degrees or less, 5 degrees or less, 3 degrees or less, 1 degree or less, or 0.1 degrees or less.

[0039] The scope of the present disclosure is not intended to be limited by the specific disclosure of preferred embodiments in this section or elsewhere herein, and may be defined by the claims presented in this section or elsewhere herein, or presented in the future. Claim language is to be interpreted broadly based on the language employed in the claims, and not limited to the examples described herein or during prosecution, which examples are to be construed as non-limiting.

Claims

1. 1. A semiconductor processing apparatus, comprising: a reaction chamber and a first exhaust port, the first exhaust port configured to remove vapors from the reaction chamber; a showerhead device connected to the reaction chamber and configured to deliver reactant vapor to the reaction chamber, a gas inlet configured to supply the reactant vapor into the showerhead device; a first showerhead plate in fluid communication with the gas inlet, the first showerhead plate comprising a plurality of openings; a second showerhead plate, a plurality of inlet ports in fluid communication with the plurality of openings, the plurality of inlet ports configured to deliver the reactant vapor to the reaction chamber; a second showerhead plate comprising a plurality of second exhaust ports configured to remove vapor from the reaction chamber; and one or more pumps connected to the first exhaust port and the plurality of second exhaust ports, the one or more pumps configured to remove vapor from the reaction chamber through the first exhaust port and the plurality of second exhaust ports; a control system configured to deliver the reactant vapor from a reactant vapor source to the reaction chamber; the first showerhead plate and the second showerhead plate cooperate to define a channel in fluid communication with the plurality of second exhaust ports and the one or more pumps; the showerhead device comprising an upper portion and a lower portion separated by a plenum, the upper portion comprising a second plurality of openings, and the lower portion comprising the first showerhead plate and a second showerhead plate; The control system pulses or alternates the reactant vapor injection and exhaust processes during processing for dynamic pressure control.

2. The semiconductor processing apparatus of claim 1 , wherein the one or more pumps comprise a plurality of pumps.

3. The semiconductor processing apparatus of claim 1 , further comprising a susceptor within the reaction chamber facing the first and second showerhead plates.

4. The semiconductor processing apparatus of claim 3 , further comprising a motor drive connected to the susceptor, the motor drive configured to adjust a distance between the susceptor and the showerhead device.

5. The semiconductor processing apparatus of claim 4 , further comprising a control system in electrical communication with the motor drive, the control system configured to adjust the distance between the susceptor and the showerhead device during etching.

6. The semiconductor processing apparatus of claim 1 , wherein said plurality of inlet ports bypass said channel.

7. The semiconductor processing apparatus of claim 1 , wherein the channels form a zigzag pattern.

8. The semiconductor processing apparatus of claim 1 , wherein the plurality of second exhaust ports are located along concentric rings on the second showerhead plate.

9. 10. The semiconductor processing apparatus of claim 1, wherein the gas inlet comprises a plurality of branched inlet lines that deliver the reactant vapor to the first showerhead plate.

10. The semiconductor processing apparatus of claim 9 , further comprising an etching reactant source in fluid communication with the first showerhead plate.

11. 1. A semiconductor processing apparatus, comprising: a reaction chamber; a reaction chamber exhaust port configured to remove vapors from the reaction chamber; a control system configured to deliver a reactant vapor from a reactant vapor source to the reaction chamber; 1. A showerhead device comprising: a plurality of distributed inlet openings in fluid communication with the reactant vapor source and the reaction chamber; a showerhead device comprising a pump and a plurality of distributed exhaust openings in fluid communication with the reaction chamber; the showerhead device comprising a first showerhead plate disposed above a second showerhead plate; the first showerhead plate includes a plurality of inlet openings, and the second showerhead plate includes a plurality of inlet ports and a plurality of exhaust ports; the first showerhead plate and the second showerhead plate cooperate to define a channel in fluid communication with a plurality of second exhaust ports and one or more pumps; the showerhead device comprising an upper portion and a lower portion separated by a plenum, the upper portion comprising a second plurality of openings, and the lower portion comprising the first showerhead plate and the second showerhead plate; The control system pulses or alternates the reactant vapor injection and exhaust processes during processing for dynamic pressure control.

12. The semiconductor processing apparatus of claim 11 , further comprising a gas inlet comprising a plurality of branched gas inlet lines for delivering vapor to the showerhead device.

13. 1. A semiconductor processing apparatus, comprising: a reaction chamber; a control system configured to deliver a reactant vapor from a reactant vapor source to the reaction chamber; 1. A showerhead device comprising: an internal plenum in communication with the pump; a plurality of exhaust openings in fluid communication with the interior plenum and the reaction chamber; a showerhead device comprising a plurality of inlet openings in fluid communication with the reactant vapor source and the reaction chamber, the plurality of inlet openings extending through the showerhead device and bypassing the internal plenum; the internal plenum comprises a labyrinth channel; the showerhead device comprises two showerhead plates, and the labyrinth channel is defined by a groove in one of the two showerhead plates, which is covered by the other of the two showerhead plates; the showerhead device comprising an upper portion and a lower portion separated by a plenum, the upper portion comprising a second plurality of openings, and the lower portion comprising a first showerhead plate and a second showerhead plate; The control system pulses or alternates the reactant vapor injection and exhaust processes during processing for dynamic pressure control.

14. The semiconductor processing apparatus of claim 13 further comprising a reaction chamber exhaust port.

15. The semiconductor processing apparatus of claim 13 further comprising one or more pumps in fluid communication with the plurality of exhaust openings.

16. 1. A method of etching a substrate, comprising: providing a reactant vapor to a showerhead device; conveying the reactant vapor to a reaction chamber through a plurality of distributed inlet openings in the showerhead device; removing vapor from the reaction chamber through a first exhaust port exposed to the reaction chamber; removing vapor from the reaction chamber through a plurality of second exhaust ports in the showerhead device; the showerhead device comprising an upper portion and a lower portion separated by a plenum, the upper portion comprising a second plurality of openings, and the lower portion comprising a first showerhead plate and a second showerhead plate; A control system is configured to deliver the reactant vapor from a reactant vapor source to the reaction chamber, and to pulse or alternate the reactant vapor injection and evacuation process during the process for dynamic pressure control.

17. The method of claim 16 , wherein the method does not etch with a plasma.

18. 17. The method of claim 16, wherein the reactant vapor has a residence time in the reaction chamber ranging from 0.1 ms to 10 seconds.

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