Showerhead device for semiconductor processing system

Abstract

To use a dual showerhead reactor to create constant partial pressures of by-products and residence time of gas molecules across a wafer.SOLUTION: In a semiconductor processing device 1, a structure of a dual showerhead reactor 10 that can be used to create constant partial pressures of by-products and residence time of gas molecules across a wafer 6 can achieve spatially uniform partial pressures, residence times and temperatures for an etchant and by-products, thus leading to uniform etch rates across the wafer. The system can include differential pumping to a reactor 2.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 a showerhead device for a semiconductor processing system. [Background technology]

[0003] 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, where 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 forming 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 pulsating delivery of etchant. For example, in some etching processes, sequential pulses of gas-phase reactants can remove minute amounts of material from a substrate in a controlled and / or selective manner. Summary of the Invention

[0004] According to one aspect, a semiconductor processing apparatus is disclosed. The apparatus may include a reaction chamber and a first exhaust port, the first exhaust port configured to remove vapor from the reaction chamber. The apparatus may also include a showerhead device connected to the reaction chamber and configured to deliver reactant vapor to the reaction chamber. The showerhead device may 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 second showerhead plate including 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 plurality of second exhaust ports configured to remove vapor from the reaction chamber. The apparatus may 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 by a first exhaust port exposed to the reaction chamber, and removing the vapor from the reaction chamber by 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 description 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. [Diagram 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. [Diagram 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 PREFERRED EMBODIMENTS

[0009] Chemical etching of microelectronic materials may have advantages over plasma etching. However, to provide a uniform etch rate across the wafer, the partial pressure, residence time, and temperature of the etching reactants (such as adsorbed reactants and / or etchants) and by-products should not vary significantly spatially above the substrate (such as a wafer). Although showerhead-type reactors can provide a uniform distribution of partial pressure of the inlet gases, the partial pressure of the by-products and the residence time of the gas molecules may not be constant across the wafer. For example, pumping to evacuate the reaction chamber is usually done from the periphery of the wafer, so 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 an etching process (e.g., a CVE process). 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 an adsorbed species on the substrate surface, and then exposes the substrate to a second gas-phase halide reactant having a second halide ligand that converts the adsorbed species to a volatile species, thereby removing at least some material from the film. In various embodiments, the film can be made of W, TiN, TiO 2 , TaN, SiN, AlO 2 , Al 2 O 3 , ZrO 2 , WO 3 , SiOCN, SiOC, SiCN, AlN or HfO 2 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 (CCl 4 or CBr 4and the like). 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 hereby incorporated 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 structure can achieve a spatially uniform partial pressure, residence time, and temperature for both the etching reactants and by-products, thus resulting in a uniform etching rate across the wafer. This apparatus can be used in any of 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 etching conformality to the substrate.

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

[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 can be 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 may be expressed as the measured reduced thickness of the etched material, or as the measured amount of the etched material based on a comparison of what was originally present and what remained 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 feature 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 a continuous flow, and the second bottom reaction chamber can have continuous pumping with leaching of reaction by-products and precursors to reduce pressure spikes. The bottom reaction chamber can supply a constant partial pressure during the precursor exposure time.

[0015] FIG. 1 illustrates a semiconductor processing apparatus 1 including a reactor 2 equipped with a dual showerhead device 10. The reactor 2 includes a reaction chamber 3 having an internal portion 4 between a susceptor 5 and the showerhead device 10. The susceptor plate 5 is within the reactor 2 and is attached to the chamber 3. The susceptor plate 5 extends upwardly 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 disposed above the susceptor 5 and the substrate 6. Although not shown, a gas manifold can supply reactants and an inert gas to the showerhead device 10, which can disperse the supplied gas as an etching 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 an etching reactant (e.g., an etchant or an adsorption reactant) (see, e.g., FIG. 2). The etchant source may be a gas cylinder and / or may include a vaporization device for vaporizing an etchant chemical that is liquid or solid in nature.

[0016] In some embodiments, the dual showerhead 10 can include a plurality of gas inlets 18 (openings) and a plurality of gas outlets 20 (openings) or exhaust ports. The inlet opening 18 and the outlet opening 20 may not communicate directly with each other, but both can communicate directly fluidly with the reaction chamber 3 below them. In some embodiments, the second gas outlet line 26 or exhaust port can provide direct fluid communication with the reaction chamber 3 to remove gas from the reaction chamber 3. As demonstrated in FIG. 1, the reactant gas (e.g., etching gas) enters the dual showerhead device 10 at the gas inlet 16, enters the upper plenum 24, and can flow towards the susceptor plate 5 holding the wafer 6. The gas outlet opening 20 of the dual showerhead 10 removes vapor from the chamber 3 through a pump 9 connected to the 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, valves 38 are connected to each gas outlet line 20, 26 and operate in series with the pump 9 to control the flow of gas exiting the reactor chamber 3.

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

[0018] One or more pumps 9 can draw residual gas 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 the gas through the exhaust port 7 of the reaction chamber 3 in the showerhead device 10 can vary in the range of about 25 m 3 / hour to about 5000 m 3 / hour, and the speed of the pump 9 is about 50 m 3 / hour to about 2500 m 3 / hour, for example 100 m 3 / hour to about 2000 m 3 / hour. In some embodiments, the pumping speed of the gas through the exhaust port 7 of the reaction chamber 3 in the reaction chamber 3 can be about 25 m 3 / hour to about 5000 m3 It can be varied within a range of time, and the pump speed is about 50 m 3 / hour to about 2500 m 3 / hour, for example, about 100 m 3 / hour to about 2000 m 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 showerhead device 10 and the exhaust port 7 of the reaction chamber 3. In some embodiments, the ratio of the pumping speed of the gas through the exhaust port 20 in the showerhead device 10 to the pumping speed of the gas through the exhaust port 7 of the reaction chamber 3 in the reaction chamber 3 can be within the range of 100:1 to 1:100, within the range of 50:1 to 1:50, within the range of 10:1 to 1:10, within the range of 5:1 to 1:5, within the range of 2:1 to 1:2, or within the range of 1.5:1 to 1:1.5. By adjusting the pumping speed, the etching process can be adjusted. Advantageously, the differential pumping system and technique disclosed herein and shown in FIG. 1 can improve the uniformity and conformality of the etching technique.

[0019] In various embodiments disclosed herein, the adjustment of the residence time of the gas species or plasma species can be used in a plasma etching reactor. Therefore, in some embodiments, the apparatus 1 can be used with a plasma etching reactor. For example, for an RF plasma reactor, as is known in the art, a remote plasma can be formed inside the showerhead 10 (the upper part 12 and the lower part 14 of the showerhead 10 function as plasma electrodes), or in situ within the reaction chamber 3 (the showerhead device 10 and the susceptor 5 and / or the wall of the reaction chamber 3 function as plasma electrodes). The embodiments disclosed herein can also be applied to adjust the plasma itself. In other embodiments, the apparatus 1 disclosed herein can be used in an etching reactor that is not a plasma etching reactor, and / or in a reactor not used for a deposition process.

[0020] In various embodiments, a throttle valve can be provided to adjust the pump 9 for adjusting the residence time by adjusting an effective pumping speed and / or using the showerhead device 10 with 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 gas molecules can be defined as τ, where τ = v / s, where v is the volume of the reaction space and s is the effective volume pumping speed. s can be defined as the total effective pumping speed and may depend on the number of holes in the showerhead device 10 and the distance x between the inlet 18 and the outlet hole 20 of the showerhead device 10. The 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. The various embodiments disclosed herein provide solutions for a constant reaction space environment, as shown, for example, 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 spacing distance x can range from a few millimeters to a few centimeters, such as in the range of 1 mm to 5 cm, 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 dispersing and exhausting gas onto 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) for supplying into an upper portion 12 of the showerhead device 10. The upper portion 12 may include an upper showerhead plate 13 (which can have a cylindrical or disk-shaped body) and an upper plenum 24 thereunder. The upper showerhead plate 13 can 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 can be manufactured separately and joined by welding both components together. In other embodiments, the inlet manifold 11 and the upper showerhead plate 13 can be joined together using a mechanical joint. In yet other embodiments, the dual showerhead 10 can be manufactured from a single piece of material. The connection between components of the showerhead 10 can result in a vacuum-type or non-vacuum-type seal. In some embodiments, a space is provided between the upper portion 12 and the lower portion 14 of the showerhead device 10, which creates the upper showerhead plenum 24.

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

[0024] Figures 3A - 3C illustrate various embodiments of the gas inlet manifold 11 above the showerhead device 10. As can be seen in Figure 3A, the gas inlet manifold 11 can have a main line 40. As can be seen in Figures 3A and 3B, the gas channels 42 can branch from the main line 40. The gas channels 42 branch from the main line 40 in multiple directions at multiple points. The main line 40 can have a slightly conical shape, where the inner diameter d of the main line 40 decreases towards the center of the showerhead. By decreasing the inner diameter d towards the center of the showerhead 10, the gas entering the showerhead 10 through the inlet 16 can move to each channel 42 in a more uniform manner. In some embodiments, as can be seen in Figure 3C, an insert 44 is mounted within the main line 40 to bifurcate the flow path. The insert 44 obstructs the flow within the main line 40 to cause the gas to flow to each branch 42 in a more uniform manner.

[0025] Figures 4 and 5 show that the lower portion 14 of the showerhead device 10 can include two plates 30, 32, and these plates define a lower or inner plenum 22 therebetween. FIG. 5 illustrates the second showerhead plate 32 shown in FIG. 4. In some embodiments, the illustrated lower or inner plenum 22 includes a hollow channel 23 that forms several concentric rings on the base of the second showerhead plate 32, while the first showerhead plate 30 can be made flat to cover the channel 23. In some embodiments, the inlet opening 18 formed in the second plate 32 is between the channels 23 and thus bypasses the inner plenum 22 (or channel) and aligns with the inlet opening 18 in the first plate 30. In the illustrated embodiment, the gas outlet opening 20 is formed through the bottom of the channel 23. The channel 23, or inner plenum 22, is connected to the pump 9 as described above. The precursor inlet opening 18, the exhaust opening 20, the hollow channel 23, and the connection 25 to the pump 9 can be arranged in a distribution pattern throughout the lower portion of the showerhead device. For example, the pattern illustrated in FIG. 5 for the reactant inlet opening, the exhaust port, and the hollow channel 23 is a circular pattern. One skilled in the art will understand that the ports of the illustrated pattern may be an incomplete pattern and that the pattern can be continuous around the entire base of the showerhead plate. In some embodiments, the precursor inlet port 18, the exhaust port 20, the hollow channel 23, and the connection 25 to the pump 9 can be arranged in patterns that are similar to or different from 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 the pump 9 that are 90 degrees relative 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 the pump 9.

[0026] FIG. 6 illustrates a top plan view of a second shower head plate 32 of the lower portion 14 of the shower head device 10 according to another embodiment. The second shower head plate 32 of FIG. 6 can have channels 23 shaped in any suitable manner to define a lower or internal 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 shower head plate 32 can include a plurality of channels 23, each channel 23 having a different pattern or a similar pattern. An inlet opening 18 can be formed outside the channels 23, while an exhaust opening 20 can be formed in fluid communication with the channels 23, while the channels 23 are connected to one or more pumps 9.

[0027] As described above, FIG. 7 illustrates a reactor 2 having the dual showerhead device 10 and a movable susceptor plate 50. The movable susceptor 50 can create a reactor 2 with a dynamic reaction space. The 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 at any time when desired, cycle by cycle, half-cycle by half-cycle, or periodically. The movable susceptor plate 50 can be adjusted through an external operation driver unit 52. The external operation driver unit 52 can comprise an analog motor or a digital motor and can be mechanically and electrically connected to the movable susceptor plate 50, whereby the external operation driver unit 52 can adjust the movable susceptor plate 50 (e.g., up and down). Using the external operation driver unit 52 connected to the apparatus 1, the gap between the wafer 6 and the showerhead device 10 (or the top plate in the case of a cross-flow reactor) can be changed over time if desired. In some embodiments, the movable susceptor plate 50 can move a distance in the range of 1 mm to 200 mm, 2 mm to 100 mm, 2 mm to 50 mm, or 3 mm to 30 mm. In some embodiments, the susceptor plate can move a distance in the range of 0.1 mm to 50 mm, 0.1 mm to 30 mm, or 0.1 mm to 20 mm. In some embodiments, the external operation driver 52 can rotate the movable susceptor plate 50. In various embodiments, the control system can communicate electrically 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 processes used in apparatus 1. In one example of an operation that utilizes both injection and evacuation through the overhead showerhead device 10, the reactants (e.g., etchant) and the evacuation process can be pulsed or alternated during the process for dynamic pressure control. Therefore, the reactant dosage can be split into a plurality of short pulses, which can improve the distribution of reactant molecules into the reaction chamber, facilitating diffusion across the entire substrate and / or rapid gas dispersion due to pressure gradients within 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 level of pressure and a higher level of pressure. The pressure gradient resulting in the reaction space during the switch-on phase pushes the precursor molecules efficiently across the entire reaction space, while the pressure gradient resulting in the reaction space during the switch-off phase pulls the gaseous reaction by-products away from the surface of the reaction space towards the gas outlet. When a relatively long conventional pulse (e.g., 1 second) is released into the reaction chamber 3, the pressure can equalize, thereby losing the dynamic dispersion effect and most of the gas flow tends to go directly towards the gas outlet. When several short pulses (e.g., 0.3 seconds three times) are released, a much more uniform distribution is achieved within the same time range.

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

[0030] Here, an example of an etching process is described. During the exposure of precursor A, the gap between the wafer 6 and the showerhead device 10 can be about 3 mm and can be optimized for the delivery of reactant A. The gap between the wafer 6 and the showerhead device 10 can be adjusted as appropriate during purging. During the exposure time of reactant B, the gap can be adjusted appropriately to deliver reactant B. The disclosed embodiments provide flexibility as appropriate for each step of the process. The apparatus described herein can be used in an etching process including a plasma etching process. In the case of a plasma process, parameters such as the plasma sheath width, ion bombardment, residence time, plasma density, etc. can be adjusted and optimized according to any step of the process.

[0031] While certain embodiments have been described, these embodiments are presented by way of example only and are not intended to limit the scope of the disclosure. In fact, the novel methods and systems described herein may be embodied in a variety of other forms. Further, various omissions, substitutions, and changes in the systems and methods described herein may be made without departing from the spirit of the 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 disclosure. Accordingly, the scope of the disclosure is defined only by reference to the appended claims.

[0032] Features, materials, characteristics, or groups described in connection with a particular aspect, embodiment, or example are to be understood as applicable to any other aspect, embodiment, or example described in this section or any other part of this specification, unless inconsistent therewith. All features disclosed in this specification (including any appended claims, abstract, and drawings), and / or all steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and / or steps are mutually exclusive. The protection is not limited to the details of any of the foregoing embodiments. The protection extends to any novel one, or any novel combination, of the features disclosed in this specification (including any appended claims, abstract, and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.

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

[0034] Moreover, operations may be depicted in the drawings or described in the specification in a particular order, and such operations need not be performed in the particular order or sequential order shown to achieve the desired result, nor do all operations need to be executed. Other operations not depicted or described can be incorporated into the exemplary methods and processes. For example, one or more additional operations can be executed before, after, simultaneously with, or between any of the described operations. Further, in other implementations, the operations may be rearranged or the order of the operations may be changed. 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 the steps shown in the figures. Depending on the embodiment, some of the above steps may be excluded, and other steps may be added. Additionally, 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 this disclosure. Also, the separation of the various system components in the above-described embodiments should not be understood to be required in all embodiments. Also, of course, the described components and systems will typically be integrated together within a single product or can be packaged within multiple products.

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

[0036] Conditional language such as "can," "could," "might," "may," etc., unless otherwise stated or otherwise understood within the context in which it is used, is generally intended to convey that a particular embodiment includes a particular feature, element, and / or step, while other embodiments do not. Thus, such conditional language is not generally intended to imply that a feature, element, and / or step is required in any way in one or more embodiments, or that one or more embodiments necessarily include logic for determining whether these features, elements, and / or steps are included in or implemented in any particular embodiment, regardless of user input or instruction.

[0037] Phrases using conjunctions such as "at least one of X, Y, and Z" are understood in the context in which they are generally used, unless otherwise stated, to convey that the item, term, etc. may be any of X, Y, or Z. Thus, such phrases using conjunctions are 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] Terms such as "about," "approximately," "generally," and "substantially" used in this specification to indicate a degree, when used in this specification, still represent a value, amount, or characteristic that is close to the described value, amount, or characteristic that implements the desired function or achieves the desired result. For example, the terms "about," "approximately," "generally," and "substantially" may refer to amounts within less than 10%, less than 5%, less than 1%, less than 0.1%, and less than 0.01% of the described amount. As another example, in certain embodiments, the terms "generally parallel" and "substantially parallel" refer to values, amounts, or characteristics that deviate 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 degree or less.

[0039] The scope of the present disclosure is not intended to be limited by the specific disclosure of the preferred embodiments in this section or other parts of this specification, and may also be defined by the claims presented in this section or other parts of this specification, or claims presented in the future. The words of the claims should be construed broadly based on the words employed in the claims and not limited to the examples described in this specification or during the application procedure, which should be construed as non-limiting.

Claims

1. 1. A semiconductor processing apparatus, comprising: a reaction chamber and a first exhaust port, the reaction chamber 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 plenum disposed between the gas inlet and the first showerhead plate, the plenum configured to transport vapor from the gas inlet to the plurality of openings; and 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 outlet openings configured to remove vapor from the reaction chamber; and one or more pumps connected to the reaction chamber exhaust port and the plurality of outlet openings, the one or more pumps configured to remove vapors from the reaction chamber through the reaction chamber exhaust port and the outlet openings; the first showerhead plate and the second showerhead plate cooperate to define channels in fluid communication with the plurality of outlet openings and the one or more pumps; the showerhead device comprises an upper portion and a lower portion separated by the plenum, the upper portion comprising a second plurality of openings, and the lower portion comprising the first showerhead plate and the second showerhead plate.

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 showerhead device.

4. A semiconductor processing apparatus as described in claim 3, further comprising a motor drive connected to the susceptor, the motor drive configured to adjust the 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 the plurality of inlet ports bypass the 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 outlet openings are positioned along concentric rings on the second plate.

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

10. The semiconductor processing apparatus of claim 1, further comprising a control system configured to deliver etching reactants from an etching reactant source to the reaction chamber.

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

12. The semiconductor processing apparatus of claim 11, wherein the control system is configured to conformally deliver the etching reactants to the substrate so that etching conformality is greater than 50%.

13. The semiconductor processing apparatus of claim 11, wherein the control system is configured to selectively deliver the etching reactants to the substrate so that the etching selectivity is greater than 10%.

14. A semiconductor processing apparatus comprising: a reaction chamber; a reaction chamber exhaust port configured to remove vapors from the reaction chamber; 1. A showerhead device comprising: a plurality of distributed inlet openings in fluid communication with a reactant vapor source and said reaction chamber; a gas inlet configured to supply a reactant vapor into the showerhead device; a plenum disposed between the gas inlet and the inlet opening, the plenum configured to convey vapor from the gas inlet to the inlet opening; a showerhead device comprising: a pump; and a plurality of distributed exhaust openings in fluid communication with the reaction chamber, the plurality of distributed exhaust openings configured to remove vapor from the reaction chamber; the showerhead device comprising an upper portion and a lower portion separated by the plenum; the showerhead device comprises a first showerhead plate disposed above a second showerhead plate; the lower portion of the showerhead device comprises the first showerhead plate and the second showerhead plate, and the upper portion comprises a second plurality of exhaust openings; The first showerhead plate and the second showerhead plate cooperate to define a channel in fluid communication with the plurality of exhaust openings and the pump.

15. The semiconductor processing apparatus of claim 14, wherein 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.

16. The semiconductor processing apparatus of claim 14, further comprising a gas inlet including multiple branched gas inlet lines for delivering steam to the showerhead device.

17. A semiconductor processing apparatus comprising: a reaction chamber; 1. A showerhead device comprising: a gas inlet configured to supply a reactant vapor into the showerhead device; an internal plenum in communication with the pump; a plurality of exhaust openings in fluid communication with the interior plenum and the reaction chamber, the plurality of exhaust openings configured to remove vapors from the reaction chamber; a plurality of inlet openings in fluid communication with a reactant vapor source and the reaction chamber, the plurality of inlet openings extending through the showerhead device and bypassing the interior plenum, the inlet openings in fluid communication with an upper plenum, the upper plenum being disposed between the gas inlet and the showerhead device; the internal plenum comprises a zigzag pattern; the showerhead device comprising two showerhead plates, the zigzag pattern being defined by grooves in one of the plates and covered by the other of the plates.

18. The semiconductor processing apparatus of claim 17, further comprising a reaction chamber exhaust port.

19. The semiconductor processing apparatus of claim 17, further comprising one or more pumps in fluid communication with the plurality of exhaust openings.

20. The semiconductor processing apparatus of claim 1, further comprising an inlet manifold, the inlet manifold being positioned between the gas inlet and the plenum.

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