Showerhead with integrated bypass channel

Abstract

A showerhead for a processing chamber includes a body having an upper surface, a lower surface, and a side surface that define a plenum, and a plurality of through-holes in the lower surface of the body. The plurality of through-holes are in fluid communication with the plenum and the processing chamber. The showerhead includes an inlet in one of the upper surface and the side surface of the body and a first passage in the body. The first passage connects the inlet to the plenum. The showerhead includes an outlet in one of the upper surface and the side surface of the body and a second passage in the body. The second passage connects the outlet to the plenum.

Description

[Technical Field]

[0001] [CROSS-REFERENCE TO RELATED APPLICATIONS] This application claims the benefit of U.S. Provisional Application No. 63 / 088,940, filed October 7, 2020. The entire disclosures of the above-referenced applications are incorporated herein by reference.

[0002] The present disclosure relates generally to substrate processing systems, and more particularly to a showerhead design with integrated flow channels for gas bypass and minimizing dead legs. [Background technology]

[0003] The background description provided herein is intended to present the contents of the present disclosure generally. Work by the presently named inventors within the scope of what is described in this Background section, as well as aspects of the description that may not otherwise be considered prior art at the time of filing, are not admitted, expressly or impliedly, as prior art against the present disclosure.

[0004] Substrate processing systems for performing deposition and / or etching typically include a processing chamber having a pedestal. A substrate, such as a semiconductor wafer, can be placed on the pedestal during processing. A gas delivery system can introduce a process gas mixture containing one or more precursors into the processing chamber to deposit a film on the substrate or etch the substrate. In some substrate processing systems, materials are deposited on the substrate using an atomic layer deposition (ALD) process. In some substrate processing systems, a plasma can be struck in the processing chamber and / or an RF bias on the pedestal can be used to activate chemical reactions.

[0005] Various gas flow paths within a gas delivery system are used to deliver process gases, carrier gases, oxidizing gases, precursor gases, and / or purge gases to a processing chamber. The gas flow paths are defined by tubing, valves, manifolds, etc. A first gas can be delivered through the gas flow channel during a first portion of the process, and either no gas or a second gas can be delivered during a second portion of the process. The first gas may temporarily remain in the gas flow channel unless a purge process is performed to clear the gas flow channel. The portion of the gas flow channel that holds stagnant gas is called a dead leg. Stagnant gas in a dead leg can decompose and cause defects on the substrate. Summary of the Invention

[0006] A showerhead for a processing chamber includes a body having an upper surface, a lower surface, and a side surface that define a plenum, and a plurality of through-holes in the lower surface of the body. The plurality of through-holes are in fluid communication with the plenum and the processing chamber. The showerhead includes an inlet in one of the upper surface and the side surface of the body and a first passage in the body. The first passage connects the inlet to the plenum. The showerhead includes an outlet in one of the upper surface and the side surface of the body and a second passage in the body. The second passage connects the outlet to the plenum.

[0007] In another feature, the outlet is downstream relative to and in fluid communication with the inlet.

[0008] In another feature, the inlet and outlet are located at opposite ends of the showerhead.

[0009] In another feature, the inlet and outlet are connected to opposite ends of the plenum.

[0010] In another feature, the inlet and outlet are located at opposite ends of the showerhead and connected to opposite ends of the plenum.

[0011] In other features, a system includes a showerhead and first and second valves connected to an inlet and an outlet, respectively, the first valve connected to a gas source, and the second valve connected to an exhaust port of a processing chamber.

[0012] In another feature, the system further comprises a controller configured to close the second valve, open the first valve to supply the first gas from the gas source to the inlet, open the second valve when the second gas is subsequently supplied from the gas source to the inlet through the first valve in place of the first gas, and close the second valve after a predetermined time.

[0013] In another feature, the side extends vertically toward the bottom of the processing chamber and the outlet is located at the bottom end of the side.

[0014] In another feature, the bottom end of the side extends beyond at least a portion of a pedestal disposed within the processing chamber.

[0015] In other features, a system includes a showerhead and first and second valves connected to an inlet and an outlet, respectively, the first valve connected to a gas source, and the second valve in fluid communication with an exhaust port of a processing chamber.

[0016] In another feature, the system further comprises a controller configured to close the second valve, open the first valve to supply the first gas from the gas source to the inlet, open the second valve when the second gas is subsequently supplied from the gas source to the inlet through the first valve in place of the first gas, and close the second valve after a predetermined time.

[0017] In another feature, the lower surface is attached to a sidewall of the processing chamber.

[0018] In another feature, the outlet is located at a bottom end of the sidewall.

[0019] In other features, a system includes a showerhead and first and second valves connected to an inlet and an outlet, respectively, the first valve connected to a gas supply, and the second valve in fluid communication with a processing chamber exhaust port located at the bottom of the processing chamber.

[0020] In another feature, the system further comprises a controller configured to close the second valve, open the first valve to supply the first gas from the gas source to the inlet, open the second valve when the second gas is subsequently supplied from the gas source to the inlet through the first valve in place of the first gas, and close the second valve after a predetermined time.

[0021] In another feature, the showerhead is mounted to a top plate of the processing chamber and has a larger diameter than a pedestal disposed within the processing chamber.

[0022] In other features, the system includes a showerhead and first and second valves disposed on a top plate and connected to an inlet and an outlet, respectively, the first valve connected to a gas supply source, and the second valve connected to an exhaust port of a processing chamber.

[0023] In another feature, the system further comprises a controller configured to close the second valve, open the first valve to supply the first gas from the gas source to the inlet, open the second valve when the second gas is subsequently supplied from the gas source to the inlet through the first valve in place of the first gas, and close the second valve after a predetermined time.

[0024] In other features, the system includes a showerhead and a first valve disposed on the top plate, the first valve connected to the inlet and the gas supply, and the outlets located at the periphery of the showerhead.

[0025] In another feature, the system further comprises a second valve connected to the outlet, the second valve in fluid communication with a processing chamber exhaust port located at the bottom of the processing chamber.

[0026] In another feature, the system further comprises a controller configured to close the second valve, open the first valve to supply the first gas from the gas source to the inlet, open the second valve when the second gas is subsequently supplied from the gas source to the inlet through the first valve in place of the first gas, and close the second valve after a predetermined time.

[0027] Further areas of applicability of the present disclosure will become apparent from the detailed description, claims, and drawings. The detailed description and specific examples are for purposes of illustration only and are not intended to limit the scope of the present disclosure. [Brief explanation of the drawings]

[0028] The present disclosure will become more fully understood from the detailed description and the accompanying drawings, wherein:

[0029] [Figure 1A] FIG. 1A illustrates an example of a substrate processing system including a processing chamber including a showerhead according to the present disclosure. [Figure 1B] FIG. 1B illustrates an example substrate processing system including a processing chamber including a showerhead according to the present disclosure.

[0030] [Figure 2] FIG. 2 is a diagram showing an example of a showerhead having a gas bypass path upstream of the showerhead.

[0031] [Figure 3A] FIG. 3A illustrates an example showerhead having a bore and a gas bypass path downstream of the showerhead in accordance with the present disclosure.

[0032] [Figure 3B] FIG. 3B illustrates an example of a showerhead having a bore and a gas bypass path through the bottom of the bore in accordance with the present disclosure. [Figure 3C]FIG. 3C illustrates an example showerhead having a bore and a gas bypass path through the bottom of the bore in accordance with the present disclosure.

[0033] [Figure 4A] FIG. 4A illustrates an example of a boreless showerhead having a chamber wall defining a bore and having a gas bypass path downstream of the showerhead in accordance with the present disclosure.

[0034] [Figure 4B] FIG. 4B illustrates an example of a boreless showerhead having a chamber wall defining a bore and having a gas bypass path through the bottom of the bore in accordance with the present disclosure.

[0035] [Figure 5A] FIG. 5A illustrates an example of a showerhead mounted on top of a processing chamber with a gas bypass path through the top of the processing chamber and downstream of the showerhead according to the present disclosure.

[0036] [Figure 5B] FIG. 5B illustrates an example of a showerhead mounted on top of a processing chamber with a gas bypass path downstream from the showerhead that opens into the processing chamber according to the present disclosure.

[0037] [Figure 6] FIG. 6 illustrates a method of operating the showerhead of FIGS. 3A-5B to provide a gas bypass path downstream of the showerhead according to the present disclosure.

[0038] In the drawings, reference numbers may be reused to refer to similar and / or identical elements. DETAILED DESCRIPTION OF THE INVENTION

[0039] Showerheads are typically designed to uniformly distribute gas flow to a substrate within a processing chamber. Uniform flow distribution is achieved by restricting gas flow from a plenum within the showerhead to multiple holes in the showerhead faceplate. However, restricting gas flow in this manner presents challenges for rapid purging and / or transitioning from one gas supply to another in processes such as atomic layer deposition (ALD) processes. There is a direct trade-off between rapid ALD cycles / transitions and uniformity; improving one generally results in a deterioration of the other.

[0040] Typically, the entire gas flow is distributed to holes in the faceplate of the showerhead, with all gas passing through the holes into the processing chamber and toward the substrate. Throughout this disclosure, the flow of gas from the showerhead holes into the processing chamber is referred to as the push, and the volume of gas that enters the processing chamber from the showerhead holes and exists between the showerhead and the substrate is referred to as the process volume.

[0041] In ALD processes, gas cycles / transitions occur frequently (e.g., on the order of 100–2,000 per substrate). A single step in an ALD cycle can last on the order of 0.1–10 seconds. The transition from Gas A to Gas B occurs by forcing Gas A into the showerhead plenum along with Gas B and then purging or evacuating Gas A from the showerhead plenum. Specifically, to transition from Gas A to Gas B, Gas A is forced out of the plenum in the showerhead with Gas B and then through the showerhead holes into the process volume. Minimizing dead volume between the valve controlling the cycling (hereafter referred to as the ALD valve) and the showerhead helps make this process faster. Therefore, the ALD valve is mounted as close to the showerhead inlet as possible.

[0042] However, this still leaves the volume between the ALD valve and the substrate as a dead volume, defined almost entirely by the showerhead geometry. For example, the feed line from the gas box to the ALD valve may typically have a volume on the order of 100-400 cc, the showerhead volume may typically be on the order of 300-600 cc for ALD processes, and the showerhead holes may have a volume on the order of 2-10 cc. Therefore, diverting the gas flow after the plenum volume and before the showerhead holes can significantly improve (i.e., reduce) cycle time.

[0043] In addition to longer ALD cycle times, the transition phase between gas cycles and flow conditions adversely affects process performance. Gas flow through the showerhead becomes relatively non-uniform as the gas flow develops to a saturated, steady state. This non-uniformity in gas flow impacts substrate uniformity, especially for processes sensitive to gas flow uniformity. Therefore, if the gas flow during the transition phase is diverted from the substrate and the substrate is exposed only to the fully developed gas flow, it is possible to improve substrate uniformity in addition to improving cycle time.

[0044] The present disclosure provides an exit path from the showerhead plenum to the chamber exhaust that diverts gas flow from the process volume and represents a less restrictive path compared to the showerhead hole pattern. Throughout this disclosure, the flow of gas that is diverted from the showerhead holes and from the process volume to the chamber exhaust via an exit path downstream of the showerhead plenum is referred to as pull.

[0045] Some substrate processing systems according to the present disclosure include a showerhead with an inlet point of connection (POC) from an ALD valve located near the edge or center of the processing chamber. Gases received from the ALD valve at the inlet are distributed to a pre-distribution plenum, a primary plenum, the showerhead holes, and the substrate, in that order. A post-distribution plenum having an equal and opposite shape to the primary plenum can be provided according to the present disclosure. The post-distribution plenum can be connected to a bypass line that runs directly to the chamber exhaust. The bypass line POC can be located on the opposite edge of the showerhead from the inlet POC, but can also be located elsewhere. Throughout this disclosure, an arrangement of two elements described as two elements positioned opposite each other includes an arrangement in which the two elements are positioned 180 degrees apart from each other, as well as other alternative arrangements of the two elements.

[0046] Because the primary plenum presents approximately 10 times less pressure drop than the showerhead holes (constituting 10 times less restriction), gas can flow through the post-distribution plenum if the bypass path through the post-distribution plenum is open. In some embodiments, the present disclosure provides a control valve for the post-distribution plenum that can be opened to bypass gas flow through the post-distribution plenum during the right phase of an ALD cycle.

[0047] In another embodiment, gas flow can be diverted from the showerhead plenum through a passageway that leads to the bottom of the showerhead bore, as described below. Because the bore terminates below the process volume (below the pedestal), gases diverted to the bottom of the showerhead bore can then be directed to the chamber exhaust without affecting the substrate. In this approach, valves can be installed within the processing chamber to control whether the passageway is open or closed.

[0048] Therefore, while in some systems for diverting waste gases, the diversion occurs at a valve manifold block located upstream of the showerhead, leaving the showerhead as a dead volume, the present disclosure provides a diversion path that is integrated into the showerhead and downstream of the showerhead. Specifically, instead of diverting gases upstream from the showerhead, the present disclosure provides a diversion path for gases in the showerhead plenum to exit the showerhead, thereby ensuring that the diverted gases do not flow to the substrate (i.e., the diversion path does not go to the process volume). The diversion path is fluidly connected to the showerhead plenum and allows gases in the plenum to exit downstream from the plenum relatively quickly. The diversion path represents a minimal dead leg between the location of the diversion valve and the process volume, leaving only the showerhead holes as dead legs, rather than the entire showerhead.

[0049] This disclosure is organized as follows. First, an example of a substrate processing system that can use a showerhead designed in accordance with the present disclosure is shown and described with reference to FIGS. 1A and 1B. An example of a gas bypass path upstream of the showerhead is shown and described with reference to FIG. 2. Then, examples of various showerhead configurations including a gas bypass path designed in accordance with the present disclosure are shown and described with reference to FIGS. 3A-5B. Next, a method of operating the showerhead shown in FIGS. 3A-5B and providing a gas bypass path in accordance with the present disclosure is shown and described with reference to FIG. 6.

[0050] 1A and 1B illustrate an example of a substrate processing system 100 including a processing chamber 102 configured to process a substrate using thermal atomic layer deposition (T-ALD). The processing chamber 102 surrounds the other components of the substrate processing system 100. The processing chamber 102 includes a substrate support (e.g., a pedestal) 104. During processing, a substrate 106 is positioned on the pedestal 104.

[0051] One or more heaters 108 (e.g., a heater array) may be disposed in a ceramic plate disposed on the metal base plate of the pedestal 104 to heat the substrate 106 during processing. One or more additional heaters, called zone heaters or primary heaters (not shown), may be disposed in ceramic plates above or below the heater 108. Additionally, although not shown, a cooling system may be disposed in the base plate of the pedestal 104 including cooling channels through which a coolant may be flowed to cool the pedestal 104, and one or more temperature sensors may be disposed in the pedestal 104 to sense the temperature of the pedestal 104.

[0052] The processing chamber 102 includes a gas distribution device 110, such as a showerhead, that introduces and distributes process gases into the processing chamber 102. Various examples of showerhead configurations designed in accordance with the present disclosure are shown and described in detail with reference to FIGS. 3A-5B. In one example shown, the showerhead 110 can include a stem portion 112 having one end connected to the top surface of the processing chamber 102. A base portion of the showerhead 110 is generally cylindrical and extends radially outward from the opposite end of the stem portion 112 at a location spaced from the top surface of the processing chamber 102. The base portion includes a plenum 113 and a faceplate 114 that includes a plurality of outlets or features (e.g., slots or through-holes) that distribute gases toward the substrate 106.

[0053] Further, although not shown, the showerhead 110 can include a heating plate and a cooling plate. The heating plate can include one or more heaters, and the cooling plate can include cooling channels through which a coolant can be circulated. Additionally, one or more temperature sensors can be disposed within the showerhead 110 to sense the temperature of the showerhead 110.

[0054] A gas delivery system 130 includes one or more gas sources 132-1, 132-2, ..., and 132-N (collectively, gas sources 132), where N is an integer greater than 1. The gas sources 132 can supply process gases, cleaning gases, purge gases, inert gases, etc. The gas sources 132 are connected to a valve manifold 140 by valves 134-1, 134-2, ..., and 134-N (collectively, valves 134) and mass flow controllers 136-1, 136-2, ..., and 136-N (collectively, mass flow controllers 136). In the example shown in FIG. 1B, the valve manifold 140 includes a plurality of valves 111-1, 111-2, ..., and 111-N (collectively, valves 111) that can be controlled to supply one or more gases from the gas sources 132 to the showerhead 110. Valve manifold 140 is located in close proximity to processing chamber 102 so that when a mixture of gases is used, the mixing of gases that occurs within valve manifold 140 occurs as close as possible to the point of entry into processing chamber 102. The output of valve manifold 140 is connected to showerhead 110. A second valve 115 connects a bypass path from plenum 113 to the chamber exhaust, as described in more detail below. In some processes, a remotely generated plasma, not shown, can be supplied to processing chamber 102.

[0055] A fluid delivery system 139 supplies coolant to the cooling system in the pedestal 104 and to the cooling channels in the showerhead 110. A temperature controller 150 can be connected to the heater 108, zone heaters, and temperature sensors in the pedestal 104 and the heating plate and temperature sensor in the showerhead 110. The temperature controller 150 can control the power supply to the heater 108 and zone heaters in the pedestal 104 and the flow of coolant through the cooling system to control the temperature of the pedestal 104 and the substrate 106. The temperature controller 150 can also control the power supply to the heaters disposed in the heating plate of the showerhead 110 and the flow of coolant through the cooling channels disposed in the cooling plate of the showerhead 110 to control the temperature of the showerhead 110.

[0056] A valve 156 and a pump 158 can be used to maintain a sub-atmospheric pressure in the processing chamber 102 during substrate processing and to evacuate reactants from the processing chamber 102. A system controller 160 controls components of the substrate processing system 100, including the valve 111 and the second valve 115 in the valve manifold 140, as described in more detail below.

[0057] Throughout the following description, the showerhead inlet is shown and described as being connected to an ALD valve connected via a gas line to a gas source (e.g., element 130 shown in FIG. 1A ). Alternatively, the inlet can be connected to a valve manifold (e.g., element 140 shown in FIG. 1A ) comprising multiple valves (e.g., element 111 shown in FIG. 1B ) connected via multiple gas lines to multiple gas sources, one or more valves in the valve manifold can be controlled and operated as described below with reference to the ALD valve.

[0058] 2 shows an example of a showerhead 300 with a gas bypass path upstream of the showerhead 300. The showerhead 300 has a bore 301, a plenum 302, and a faceplate 304 containing multiple outlets or features (e.g., slots or through-holes). A valve (referred to as an ALD valve as described above) 306 connected to a gas supply via a first gas line 314 is located near the edge or center of a processing chamber 308 adjacent to an inlet 310 of the showerhead 300. The inlet 310 is adjacent to the plenum 302. A passage 312 in the showerhead 300 between the inlet 310 and the plenum 302 connects the inlet 310 to the plenum 302.

[0059] A first port of the ALD valve 306 is connected to a gas supply via a first gas line 314. A second port of the ALD valve 306 is connected to the inlet 310 via a second gas line 316. A third port of the ALD valve 306 is connected to an exhaust facility via a third gas line (called a gas bypass path) 318, to which a chamber exhaust 320 is connected.

[0060] During an ALD process, in each ALD cycle, the showerhead 300 receives gas A, followed by gas B, from a gas supply through first and second gas lines 314, 316 via an ALD valve 306. The gases enter the showerhead 300 through an inlet 310 and a passage 312 into a plenum 302 of the showerhead 300.

[0061] When receiving each gas, the first and second ports of ALD valve 306 are open, and the third port of ALD valve 306 is closed. The showerhead 300 distributes each gas from the plenum 302 through an outlet in the faceplate 304 toward a substrate 322 disposed on a pedestal 324 within a processing chamber 308.

[0062] When transitioning from Gas A to Gas B in an ALD cycle, Gas B is flowed through the first and second ports of ALD valve 306, and a third port of ALD valve 306, connected to gas bypass path 318, is opened to bypass Gas A to an exhaust facility connected to chamber exhaust 320. The third port of ALD valve 306 is then closed, and Gas B is dispersed from plenum 302 through an outlet in faceplate 304 toward substrate 322. This process is repeated when transitioning from Gas B to Gas A.

[0063] In the showerhead 300, the entire gas flow in the plenum 302 is distributed to the holes in the faceplate 304, with all gases passing through the holes in the faceplate 304 into the processing chamber 308 toward the substrate 322. To transition from Gas A to Gas B, Gas B first pushes Gas A from the plenum 302 through the holes in the faceplate 304 into the process volume (the region between the showerhead faceplate 304 and the substrate 322), and then Gas B flows from the plenum 302 through the holes in the faceplate 304 into the process volume.

[0064] The ALD valve 306 is mounted as close as possible to the gas inlet 310 of the showerhead 300 to minimize the amount of dead volume between the ALD valve 306 and the showerhead 300. However, this still leaves the volume between the ALD valve 306 and the substrate 322 as dead volume that is almost completely defined by the geometry of the showerhead 300.

[0065] 3A-5B show various examples of showerhead designs according to the present disclosure that include a gas bypass path downstream of the showerhead plenum rather than upstream of the showerhead. By bypassing the gas flow after the plenum volume and before the showerhead holes, cycle time is significantly improved (i.e., reduced) and uniformity is improved.

[0066] 3A-3C show showerheads with a bore. 4A and 4B show boreless showerheads in which the walls of the processing chamber define the bore. 5A and 5B show showerheads attached to the top of a processing chamber (e.g., mounted directly to the top of the processing chamber or mounted using a chandelier-like stem portion). Each of these configurations, with their respective gas bypass paths, will now be described in further detail.

[0067] 3A shows an example of a showerhead 350 having a bore 351 and a gas bypass path downstream of a plenum 352 of the showerhead 350 in accordance with the present disclosure. The showerhead 350 includes the plenum 352 and a faceplate 354 that includes multiple outlets or features (e.g., slots or through-holes).

[0068] A first valve (also referred to as an ALD valve, as discussed above) 356 is located at the edge or center of the processing chamber (e.g., element 102 shown in FIG. 1A ) adjacent to an inlet 360 of a showerhead 350. The inlet 360 is adjacent to a plenum 352. A first passage 362 in the showerhead 350 between the inlet 360 and the plenum 352 connects the inlet 360 to the plenum 352.

[0069] A first port of first valve 356 is connected to a gas source (e.g., element 130 shown in FIG. 1A) via first gas line 364. A second port of first valve 356 is connected to inlet 360 via second gas line 366. First valve 356 is not connected to an exhaust facility to which a chamber exhaust (e.g., similar to element 320 shown in FIG. 2) is connected.

[0070] The showerhead 350 includes an outlet 368 at an opposite end from the inlet 360. The outlet 368 is proximate to the plenum 352. A second valve 372 is disposed at an opposite end of the showerhead 350 from the first valve 356. The second valve 372 is proximate to the edge of the processing chamber. A second passage 370 in the showerhead 350 between the outlet 368 and the plenum 352 connects the outlet 368 to the plenum 352. A first port of the second valve 372 is connected to the outlet 368 via a third gas line 374. A second port of the second valve 372 is connected to an exhaust facility to which the chamber exhaust is connected via a fourth gas line 376.

[0071] The second passage 370, the third gas line 374, and the second valve 372 constitute a gas bypass path for the showerhead 350. The gas bypass path formed by the second passage 370, the third gas line 374, and the second valve 372 (hereinafter, gas bypass paths 370, 374, 372) is integrated into the showerhead 350 and is downstream of the plenum 352 of the showerhead 350.

[0072] During an ALD process, in each ALD cycle, the showerhead 350 receives Gas A, followed by Gas B, from a gas supply through first and second gas lines 364, 366 via a first valve 356. Gases enter the showerhead 350 through an inlet 360 and a first passage 362 into a plenum 352 of the showerhead 350. A controller (e.g., element 160 shown in FIG. 1A ) controls the first and second valves 356, 372 to operate the ports of the first and second valves 356, 372 as follows:

[0073] When receiving each gas, the first and second ports of the first valve 356 are open, and the first port of the second valve 372 is closed. The second port of the second valve 372 may be open or closed. The showerhead 350 distributes each gas through an outlet in the faceplate 354 toward a substrate 380 disposed on a pedestal 382 within the processing chamber.

[0074] When transitioning from Gas A to Gas B in an ALD cycle, Gas B is flowed into plenum 352 through first and second ports of first valve 356, first and second gas lines 364, 366, inlet 360, and first passage 362. The first port (and second port, if closed) of second valve 372 is opened to connect plenum 352 to gas bypass paths 370, 374, 372. Residual Gas A in plenum 352 is diverted through gas bypass paths 370, 374, 372 and via fourth gas line 376 to an exhaust facility.

[0075] During the transition, gas bypass paths 370, 374, 372 divert gas flow from the process volume to the chamber exhaust, representing a less restrictive path to the chamber exhaust compared to the hole pattern in the showerhead 350. The first port (and optionally the second port) of the second valve 372 is then closed, and Gas B is dispersed from the plenum 352 toward the substrate 380 via an outlet in the faceplate 354. This process is repeated when transitioning from Gas B to Gas A.

[0076] During each transition, gas bypass paths 370, 374, 372 provide a path for gases in plenum 352 to exit showerhead 350 so that the path does not go to substrate 380 (i.e., does not go to the process volume between showerhead 350 and substrate 380). Gas bypass paths 370, 374, 372 allow gases in plenum 352 to exit downstream from plenum 352 relatively quickly, representing a minimal dead leg between second valve 372 and the process volume, leaving only the volume of the holes in faceplate 354 as the dead leg, rather than the entire showerhead 350.

[0077] 3B and 3C show an example of a showerhead 400 having a bore 401 and a gas bypass path through a valve at the bottom of the bore 401 of the showerhead 400 in accordance with the present disclosure. In FIG. 3C, the outer diameter of the bore 401 is approximately the same as the diameter of the sidewall of a processing chamber 402 (e.g., element 102 shown in FIG. 1A). During transition, gas passes through a valve at the bottom of the bore 401 and enters a region of the processing chamber 402 below a pedestal 404 disposed within the processing chamber 402. Because the gas passes through the bottom of the bore 401 and into the region below the pedestal 404, the gas exiting the gas bypass path does not react with a substrate 406 disposed on the pedestal 404. Instead, the gas from the gas bypass path exits the processing chamber 402 through a chamber exhaust 408.

[0078] 3B, showerhead 400 includes a plenum 410 and a faceplate 412 that includes a plurality of outlets or features (e.g., slots or through-holes). Showerhead 400 includes an inlet 414 adjacent to plenum 410. A first passageway 416 within showerhead 400 between inlet 414 and plenum 410 connects inlet 414 to plenum 410.

[0079] A first valve (also referred to as an ALD valve, as discussed above) 418 is located at the edge or center of the processing chamber 402 adjacent to the inlet 414 of the showerhead 400. A first port of the first valve 418 is connected to a gas source (e.g., element 130 shown in FIG. 1A ) via a first gas line 420. A second port of the first valve 418 is connected to the inlet 414 via a second gas line 422. The first valve 418 is not connected to the exhaust facility to which the chamber exhaust 408 is connected.

[0080] A second valve 424 and a third valve 426 are disposed at the bottom of the bore 401 at opposite ends of the bore 401. Second and third passages 428 and 430 in the bore 401 between the plenum 410 and first ports of the second and third valves 424, 426 connect opposite ends of the plenum 410 to the first ports of the second and third valves 424, 426, respectively. The second ports of the second and third valves 424, 426 are configured to open into the processing chamber 402 and are in fluid communication with a chamber exhaust 408 connected to an exhaust facility.

[0081] The second and third passages 428, 430 and the second and third valves 424, 426 constitute a gas bypass path for the showerhead 400. The gas bypass path formed by the second and third passages 428, 430 and the second and third valves 424, 426 (hereinafter, bypass paths 428, 424, 430, 426) is integrated into the showerhead 400 and is downstream of the plenum 410 of the showerhead 400.

[0082] During an ALD process, in each ALD cycle, the showerhead 400 receives Gas A, followed by Gas B, from a gas supply through first and second gas lines 420, 422 via a first valve 418. Gases enter the showerhead 400 through an inlet 414 and a first passage 416 into a plenum 410 of the showerhead 400. A controller (e.g., element 160 shown in FIG. 1A ) controls the first, second, and third valves 418, 424, 426 to operate the ports of the first, second, and third valves 418, 424, 426 as follows:

[0083] When receiving each gas, the first and second ports of the first valve 418 are open, and the first ports of the second and third valves 424, 426 are closed. The second ports of the second and third valves 424, 426 may be open or closed. The showerhead 400 distributes each gas through an outlet in the faceplate 412 toward a substrate 406 disposed on a pedestal 404 in the processing chamber 402.

[0084] When transitioning from Gas A to Gas B in an ALD cycle, Gas B is flowed into plenum 410 through first and second ports of first valve 418, first and second gas lines 420, 422, inlet 414, and first passageway 416. First ports (and second ports, if closed) of second and third valves 424, 426 are opened to connect plenum 410 to gas bypass paths 428, 424, 430, 426. Residual Gas A in plenum 410 is diverted through gas bypass paths 428, 424, 430, 426 into the exhaust system via chamber exhaust 408. Because the second ports of the second and third valves 424 , 426 open into the processing chamber 402 below the pedestal 404 , residual gas A exiting the second ports of the second and third valves 424 , 426 does not react with the substrate 406 .

[0085] During the transition, gas bypass paths 428, 424, 430, 426 divert gas flow from the process volume to the chamber exhaust 408, presenting a less restrictive path to the chamber exhaust 408 compared to the hole pattern of the showerhead 400. The first port (and optionally the second port) of the second and third valves 424, 426 are then closed, and Gas B is dispersed from the plenum 410 towards the substrate 406 via an outlet in the faceplate 412. This process is repeated when transitioning from Gas B to Gas A.

[0086] During each transition, the gas bypass paths 428, 424, 430, 426 provide a path for gases in the plenum 410 to exit the showerhead 400 so that the path does not go to the substrate 406 (i.e., does not go to the process volume between the showerhead 400 and the substrate 406). The gas bypass paths 428, 424, 430, 426 allow gases in the plenum 410 to exit downstream from the plenum 410 relatively quickly, representing minimal dead legs between the second and third valves 424, 426 and the process volume, leaving only the volume of the holes in the faceplate 412 as the dead legs, rather than the entire showerhead 400.

[0087] In some embodiments, the second and third valves 424, 426 may be omitted. Gases from the plenum 410 can enter the region of the processing chamber 402 below the pedestal 404 through the passages 428, 430 and flow toward the chamber exhaust 408 without reacting with the substrate 406.

[0088] 4A shows an example of a boreless showerhead 450 according to the present disclosure having a chamber wall defining a bore 451 and having a gas bypass path downstream of the showerhead 450. The showerhead 450 includes a plenum 452 and a faceplate 454 including a plurality of outlets or features (e.g., slots or through-holes).

[0089] A first valve (also referred to as an ALD valve, as discussed above) 456 is located at the edge or center of the processing chamber (e.g., element 102 shown in FIG. 1A ) adjacent to an inlet 460 of a showerhead 450. The inlet 460 is adjacent to a plenum 452. A first passage 462 in the showerhead 450 between the inlet 460 and the plenum 452 connects the inlet 460 to the plenum 452.

[0090] A first port of first valve 456 is connected to a gas source (e.g., element 130 shown in FIG. 1A) via a first gas line 464. A second port of first valve 456 is connected to inlet 460 via a second gas line 466. First valve 456 is not connected to an exhaust facility to which a chamber exhaust (e.g., similar to element 408 shown in FIG. 3C) is connected.

[0091] The showerhead 450 includes an outlet 468 at an opposite end from the inlet 460. The outlet 468 is proximate to the plenum 452. A second valve 472 is disposed at an opposite end of the showerhead 450 from the first valve 456. The second valve 472 is proximate to the edge of the processing chamber. A second passage 470 in the showerhead 450 between the outlet 468 and the plenum 452 connects the outlet 468 to the plenum 452. A first port of the second valve 472 is connected to the outlet 468 via a third gas line 474. A second port of the second valve 472 is connected to an exhaust facility to which the chamber exhaust is connected via a fourth gas line 476.

[0092] The second passage 470, the third gas line 474, and the second valve 472 constitute a gas bypass path for the showerhead 450. The gas bypass path formed by the second passage 470, the third gas line 474, and the second valve 472 (hereinafter, gas bypass paths 470, 474, 472) is integrated into the showerhead 450 and is downstream of the plenum 452 of the showerhead 450.

[0093] During an ALD process, in each ALD cycle, the showerhead 450 receives Gas A, followed by Gas B, from a gas supply through first and second gas lines 464, 466 via a first valve 456. Gases enter the showerhead 450 through an inlet 460 and a first passage 462 into the plenum 452. A controller (e.g., element 160 shown in FIG. 1A ) controls the first and second valves 456, 472 to operate the ports of the first and second valves 456, 472 as follows:

[0094] When receiving each gas, the first and second ports of the first valve 456 are open, and the first port of the second valve 472 is closed. The second port of the second valve 472 can be open or closed. The showerhead 450 distributes each gas through an outlet in the faceplate 454 toward a substrate 480 positioned on a pedestal 482 within the processing chamber.

[0095] When transitioning from Gas A to Gas B in an ALD cycle, Gas B is flowed into plenum 452 through first and second ports of first valve 456, first and second gas lines 464, 466, inlet 460, and first passageway 462. The first port (and second port, if closed) of second valve 472 is opened to connect plenum 452 to gas bypass paths 470, 474, 472. Residual Gas A in plenum 452 is diverted through gas bypass paths 470, 474, 472 and via fourth gas line 476 to an exhaust facility.

[0096] During the transition, gas bypass paths 470, 474, 472 divert gas flow from the process volume to the chamber exhaust, representing a less restrictive path to the chamber exhaust compared to the hole pattern in the showerhead 450. The first port (and optionally the second port) of the second valve 472 is then closed, and Gas B is dispersed from the plenum 452 toward the substrate 480 via an outlet in the faceplate 454. This process is repeated when transitioning from Gas B to Gas A.

[0097] During each transition, gas bypass paths 470, 474, 472 provide a path for gases in plenum 452 to exit showerhead 450 so that the path does not go to substrate 480 (i.e., does not go to the process volume between showerhead 450 and substrate 480). Gas bypass paths 470, 474, 472 allow gases in plenum 452 to exit downstream from plenum 452 relatively quickly, representing a minimal dead leg between second valve 472 and the process volume, leaving only the volume of the holes in faceplate 454 as the dead leg, rather than the entire showerhead 450.

[0098] 4B shows an example of a boreless showerhead 500 according to the present disclosure, having a chamber wall defining a bore 501 and having a gas bypass path through a valve at the bottom of the bore 501. During transition, gas passes through the bottom of the bore 501 into a region of the processing chamber below a pedestal 504 disposed within the processing chamber (e.g., similar to element 102 shown in FIG. 1A). Because the gas passes through the bottom of the bore 501 into a region below the pedestal 504, the gas exiting the gas bypass path does not react with a substrate 506 disposed on the pedestal 504. Instead, the gas from the gas bypass path exits the processing chamber through a chamber exhaust (e.g., similar to element 408 shown in FIGS. 3A-3C).

[0099] The showerhead 500 includes a plenum 510 and a faceplate 512 that includes a plurality of outlets or features (e.g., slots or through-holes). The showerhead 500 includes an inlet 514 adjacent to the plenum 510. A first passage 516 in the showerhead 500 between the inlet 514 and the plenum 510 connects the inlet 514 to the plenum 510.

[0100] A first valve (also referred to as an ALD valve, as discussed above) 518 is located at the edge or center of the processing chamber adjacent to the inlet 514 of the showerhead 500. A first port of the first valve 518 is connected to a gas source (e.g., element 130 shown in FIG. 1A ) via a first gas line 520. A second port of the first valve 518 is connected to the inlet 514 via a second gas line 522. The first valve 518 is not connected to the exhaust facility to which the chamber exhaust is connected.

[0101] A second valve 524 and a third valve 526 are disposed at opposite ends of the bottom of bore 501. Second and third passages 528 and 530 in bore 501 are connected to first ports of second and third valves 524, 526, respectively. Second and third passages 528 and 530 in bore 501 are also connected to fourth and fifth passages 529 and 531, respectively, in showerhead 500, which are connected to first and second opposing ends of plenum 510, respectively.

[0102] For example, to connect a second passage 528 in the bore 501 to a fourth passage 529 in the showerhead 500, mating holes and slots may be present in the bore 501 and the showerhead 500, respectively (or vice versa), with a seal surrounding the holes and slots. Similarly, to connect a third passage 530 in the bore 501 to a fifth passage 531 in the showerhead 500, mating holes and slots may be present in the bore 501 and the showerhead 500, respectively (or vice versa), with a seal surrounding the perimeter.

[0103] Thus, a first end of the plenum 510 is connected to a first port of a second valve 524 via a fourth passage 529 in the showerhead 500 and a second passage 528 in the bore 501, and a second end of the plenum 510 is connected to a first port of a third valve 526 via a fifth passage 531 in the showerhead 500 and a third passage 530 in the bore 501. Second ports of the second and third valves 524, 526 are configured to open into the processing chamber and are in fluid communication with a chamber exhaust connected to an exhaust facility.

[0104] The fourth, second, fifth, and third passages 529, 528, 531, 530 and the second and third valves 524, 526 constitute a gas bypass path for the showerhead 500. The gas bypass paths formed by the fourth, second, fifth, and third passages 529, 528, 531, 530 and the second and third valves 524, 526 (hereinafter, gas bypass paths 529, 528, 524, 531, 530, 526) are integrated into the showerhead 500 and are downstream of the plenum 510 of the showerhead 500.

[0105] During an ALD process, in each ALD cycle, the showerhead 500 receives Gas A, followed by Gas B, from a gas supply through first and second gas lines 520, 522 via a first valve 518. Gases enter the showerhead 500 through an inlet 514 and a first passage 516 into a plenum 510. A controller (e.g., element 160 shown in FIG. 1A ) controls the first, second, and third valves 518, 524, 526 to operate the ports of the first, second, and third valves 518, 524, 526 as follows:

[0106] When receiving each gas, the first and second ports of the first valve 518 are open, and the first ports of the second and third valves 524, 526 are closed. The second ports of the second and third valves 524, 526 may be open or closed. The showerhead 500 distributes each gas through an outlet in the faceplate 512 toward a substrate 506 disposed on a pedestal 504 within the processing chamber.

[0107] When transitioning from Gas A to Gas B in an ALD cycle, Gas B is flowed into plenum 510 through first and second ports of first valve 518, first and second gas lines 520, 522, inlet 514, and first passageway 516. First ports (and second ports, if closed) of second and third valves 524, 526 are opened to connect plenum 510 to gas bypass paths 529, 528, 524, 531, 530, 526. Residual Gas A in plenum 510 is diverted through gas bypass paths 529, 528, 524, 531, 530, 526 into the exhaust system via the chamber exhaust. Because the second ports of the second and third valves 524 , 526 open into the processing chamber below the pedestal 504 , residual gas A exiting the second ports of the second and third valves 524 , 526 does not react with the substrate 506 .

[0108] During the transition, gas bypass paths 529, 528, 524, 531, 530, 526 divert gas flow from the process volume to the chamber exhaust, representing a less restrictive path to the chamber exhaust compared to the hole pattern of the showerhead 500. The first port (and optionally the second port) of the second and third valves 524, 526 are then closed, and Gas B is dispersed from the plenum 510 toward the substrate 506 via an outlet in the faceplate 512. This process is repeated when transitioning from Gas B to Gas A.

[0109] During each transition, gas bypass paths 529, 528, 524, 531, 530, 526 provide a path for gases in plenum 510 to exit showerhead 500 so that the path does not go to substrate 506 (i.e., does not go to the process volume between showerhead 500 and substrate 506). Gas bypass paths 529, 528, 524, 531, 530, 526 allow gases in plenum 510 to exit downstream from plenum 510 relatively quickly, representing minimal dead legs between second and third valves 524, 526 and the process volume, leaving only the volume of holes in faceplate 512 as the dead legs, rather than the entire showerhead 500.

[0110] In some embodiments, the second and third valves 524, 526 may be omitted. Gases from the plenum 510 can enter the region of the processing chamber below the pedestal 504 through passages 528, 530 and flow toward the chamber exhaust without reacting with the substrate 506.

[0111] FIG. 5A shows an example of a showerhead 550 according to the present disclosure. The showerhead 550 is attached to the top of a processing chamber 551 (e.g., element 102 shown in FIG. 1A), with only the top and sidewalls shown. The showerhead 550 is mounted flush with (i.e., directly on) the top of the processing chamber 551 or is mounted using a chandelier-like stem portion 553. The showerhead 550 includes a plenum 552 and a faceplate 554 that includes multiple outlets or features (e.g., slots or through-holes). The showerhead 550 includes a gas bypass path downstream of the plenum 552 according to the present disclosure.

[0112] A first valve (also referred to as an ALD valve, as discussed above) 556 is located at the edge or center of the processing chamber 551 adjacent to an inlet 560 of the showerhead 550. The inlet 560 is adjacent to a plenum 552. A first port of the first valve 556 is connected to a gas source (e.g., element 130 shown in FIG. 1A) via a first gas line 564. A second port of the first valve 556 is connected to the chamber wall via a second gas line 566. The first valve 556 is not connected to the exhaust facility to which the chamber exhaust is connected.

[0113] A second valve 572 is located at the opposite end of the showerhead 550 from the first valve 556. The second valve 572 is proximate the edge of the processing chamber 551 and the outlet 568 of the showerhead 550. A first port of the second valve 572 is connected to the chamber wall via a third gas line 574. A second port of the second valve 572 is connected to an exhaust facility via a fourth gas line 576 to which the chamber exhaust is connected.

[0114] A first passage 562 in the showerhead 550 between the inlet 560 and a first end of the plenum 552 connects the inlet 560 to the first end of the plenum 552. A second passage 570 in the showerhead 550 between the outlet 568 and a second end opposite the first end of the plenum 552 connects the outlet 568 to the second end of the plenum 552. A third passage 567 in the chamber wall connects to the second gas line 566. A fourth passage 569 in the chamber wall connects to the third gas line 574.

[0115] When the showerhead 550 is connected to the processing chamber 551 by the stem portion 553, a fifth gas line 571 is connected between the inlet 560 and a third passage 567 in the chamber wall, and a sixth gas line 573 is connected between the outlet 568 and a fourth passage 569 in the chamber wall. Thus, when the showerhead 550 is connected to the processing chamber 551 by the stem portion 553, a second port of the first valve 556 is connected to the inlet 560 of the showerhead 550 via the second gas line 566, the third passage 567 in the chamber wall, and the fifth gas line 571, and a second port of the second valve 572 is connected to the outlet 568 of the showerhead 550 via the third gas line 574, the fourth passage 569 in the chamber wall, and the sixth gas line 573.

[0116] If the showerhead 550 is mounted flush with (i.e., directly to) the processing chamber 551 without the stem portion 553, the fifth and sixth gas lines 571, 573 are omitted. A third passage 567 in the chamber wall is connected to a first passage 562 in the showerhead 550 at an inlet 560, and a fourth passage 569 in the chamber wall is connected to a second passage 570 in the showerhead 550 at an outlet 568. For example, at each of the inlet 560 and outlet 568, a mating hole and slot may be present in the chamber wall and showerhead 550, respectively (or vice versa), with a seal surrounding the hole and slot.

[0117] Thus, when the showerhead 550 is mounted flush with the processing chamber 551, the second port of the first valve 556 is connected to a first end of the plenum 552 via a second gas line 566, a third passage 567 in the chamber wall, and a first passage 562 in the showerhead 550, and the second port of the second valve 572 is connected to a second end of the plenum 552 via a third gas line 574, a fourth passage 569 in the chamber wall, and a second passage 570 in the showerhead 550.

[0118] The second passage 570 in the showerhead 550, the sixth gas line 573, if present (depending on whether the showerhead 550 is attached to the processing chamber 551 directly or via a stem portion 553), the fourth passage 569 in the chamber wall, the third gas line 574, and the second valve 572 constitute a gas bypass path for the showerhead 550. The gas bypass path formed by the second passage 570, the sixth gas line 573, if present, the fourth passage 569, the third gas line 574, and the second valve 572 (hereinafter, gas bypass paths 570, 573, 569, 574, 572) is integrated into the showerhead 550 and is downstream of the plenum 552 of the showerhead 550.

[0119] During an ALD process, in each ALD cycle, the showerhead 550 receives Gas A, followed by Gas B, from a gas supply through first and second gas lines 564, 566, a third passage 567, and, if present, a fifth gas line 571 via a first valve 556. Gases enter the plenum 552 through an inlet 560 and a first passage 562. A controller (e.g., element 160 shown in FIG. 1A ) controls the first and second valves 556, 572 to operate the ports of the first and second valves 556, 572 as follows:

[0120] When receiving each gas, the first and second ports of the first valve 556 are open, and the first port of the second valve 572 is closed. The second port of the second valve 572 can be open or closed. The showerhead 550 distributes each gas through an outlet in the faceplate 554 toward a substrate 580 disposed on a pedestal 582 within the processing chamber 551.

[0121] When transitioning from Gas A to Gas B in an ALD cycle, Gas B is flowed into plenum 552 through the first and second ports of first valve 556, first and second gas lines 564, 560, third passage 567, fifth gas line 571, if present, inlet 560, and first passage 562. The first port (and second port, if closed) of second valve 572 is opened to connect plenum 552 to gas bypass paths 570, 573, 569, 574, 572. Residual Gas A in plenum 552 is diverted through gas bypass paths 570, 573, 569, 574, 572 and through fourth gas line 576 to an exhaust facility.

[0122] During the transition, gas bypass paths 570, 573, 569, 574, 572 divert gas flow from the process volume to the chamber exhaust, representing a less restrictive path to the chamber exhaust compared to the hole pattern in the showerhead 550. The first port (and optionally the second port) of the second valve 572 is then closed, and Gas B is dispersed from the plenum 552 towards the substrate 580 via an outlet in the faceplate 554. This process is repeated when transitioning from Gas B to Gas A.

[0123] During each transition, gas bypass paths 570, 573, 569, 574, 572 provide a path for gases in plenum 552 to exit showerhead 550 so that the path does not go to substrate 580 (i.e., does not go to the process volume between showerhead 550 and substrate 580). Gas bypass paths 570, 573, 569, 574, 572 allow gases in plenum 552 to exit downstream from plenum 552 relatively quickly, representing a minimal dead leg between second valve 572 and the process volume, leaving only the volume of holes in faceplate 554 as the dead leg, rather than the entire showerhead 550.

[0124] 5B shows an example of a showerhead 600 with a gas bypass path downstream of the showerhead 600 according to the present disclosure. The showerhead 600 is attached to the top of a processing chamber 601 (e.g., element 102 shown in FIG. 1A), with only the top and side walls shown. The showerhead 600 is mounted flush with (i.e., directly on) the top of the processing chamber 601 or is mounted using a chandelier-like stem portion 603.

[0125] The outer diameter of the showerhead 600 is larger than the outer diameter of a pedestal 604 disposed within the processing chamber 601. During transition, gases pass around the showerhead 600 and enter the processing chamber 601. Because the diameter of the showerhead 600 is larger than the diameter of the pedestal 604, gases exiting around the showerhead 600 tend to flow toward the bottom of the processing chamber 601 without reacting with the substrate 506 disposed on the pedestal 604. Gases exiting around the showerhead 600 flow toward the bottom of the processing chamber 601 and exit the processing chamber 601 through a chamber exhaust port (e.g., similar to element 408 shown in Figures 3A-3C).

[0126] The showerhead 600 includes a plenum 610 and a faceplate 612 including a plurality of outlets or features (e.g., slots or through-holes). The showerhead 600 includes an inlet 614 adjacent to the plenum 610. A first passageway 616 within the showerhead 500 between the inlet 614 and the plenum 610 connects the inlet 614 to the plenum 610. The showerhead 600 includes outlets 615 and 617 at first and second opposing ends of the showerhead 600. Second and third passageways 619 and 621 within the showerhead 500 between the outlets 615 and 617 and the opposing ends of the plenum 610 connect the outlets 615 and 617, respectively, to the plenum 610.

[0127] A first valve (also referred to as an ALD valve, as discussed above) 618 is located at the edge or center of the processing chamber 601 adjacent to the inlet 614 of the showerhead 500. A first port of the first valve 618 is connected to a gas supply (e.g., element 130 shown in FIG. 1A ) via a first gas line 620. A second port of the first valve 618 is connected to the chamber wall via a second gas line 622. A fourth passage 623 in the chamber wall is connected to the second gas line 622. The first valve 614 is not connected to the exhaust facility to which the chamber exhaust is connected.

[0128] When the showerhead 600 is connected to the processing chamber 601 by the stem portion 603, the third gas line 625 is connected between the inlet 614 and the fourth passage 623 in the chamber wall. Thus, when the showerhead 600 is connected to the processing chamber 601 by the stem portion 603, the second port of the first valve 618 is connected to the inlet 614 of the showerhead 600 via the second gas line 622, the fourth passage 623 in the chamber wall, and the third gas line 625.

[0129] When the showerhead 600 is mounted flush with (i.e., directly to) the processing chamber 601 without the stem portion 603, the third gas line 625 is omitted. The fourth passage 623 in the chamber wall is connected to the first passage 616 in the showerhead 600 at the inlet 614. For example, at the inlet 614, a mating hole and slot may be present in the chamber wall and the showerhead 600, respectively (or vice versa), with a seal surrounding the hole and slot. Thus, when the showerhead 600 is mounted directly to the processing chamber 601, the second port of the first valve 618 is connected to the first end of the plenum 610 via the second gas line 622, the fourth passage 623 in the chamber wall, and the first passage 616 in the showerhead 600.

[0130] In this embodiment, second and third passages 619, 621 within showerhead 600 and outlets 615, 617 of showerhead 600 constitute a gas bypass path for showerhead 600. The gas bypass path formed by second and third passages 619, 621 and outlets 615, 617 (hereinafter gas bypass paths 619, 615, 621, 617) is integrated into showerhead 600 and is downstream of plenum 610 of showerhead 600.

[0131] In another embodiment, second and third valves 624 and 626 may be positioned proximate outlets 615 and 617, respectively, of plenum 610. First ports of second and third valves 624 and 626 may be connected to outlets 615 and 617 via fourth and fifth gas lines 628 and 630, respectively. Second ports of second and third valves 624 and 626 are configured to open into processing chamber 601 and are in fluid communication with a chamber exhaust connected to an exhaust facility. Again, because the diameter of showerhead 600 is larger than the diameter of pedestal 604, gases exiting the second ports of second and third valves 624 and 626 do not react with substrate 606 on the pedestal and flow toward the bottom of processing chamber 601 and exit through the chamber exhaust.

[0132] In this other embodiment including second and third valves 624, 626, second and third passages 619 and 621, fourth and fifth gas lines 628 and 630, and second and third valves 624 and 626 within showerhead 600 constitute a gas bypass path for showerhead 600. The gas bypass path formed by second and third passages 619, 621, fourth and fifth gas lines 628, 630, and second and third valves 624, 626 (hereinafter gas bypass paths 619, 628, 624, 621, 630, 626) is integrated into showerhead 600 and is downstream of plenum 610 of showerhead 600.

[0133] During an ALD process, in each ALD cycle, the showerhead 600 receives Gas A, followed by Gas B, from a gas supply through first and second gas lines 620, 622, a fourth passage 623, and, if present (i.e., when the showerhead is attached with stem portion 603), a third gas line 625 via a first valve 618. Gases enter the plenum 610 through an inlet 614 and a first passage 616. A controller (e.g., element 160 shown in FIG. 1A ) controls the ports of the first valve 618 and second and third valves 624, 626, if present, to operate as follows:

[0134] When receiving each gas, the first and second ports of the first valve 618 are open, and the first ports of the second and third valves 624, 626 (if used) are closed. The second ports of the second and third valves 624, 626 may be open or closed. In the absence of the second and third valves 624, 626, the outlets 615 and 617 of the showerhead 600 are in fluid communication with the processing chamber 601. The showerhead 600 distributes each gas through the outlets in the faceplate 612 toward a substrate 606 disposed on a pedestal 504 within the processing chamber 601.

[0135] When transitioning from Gas A to Gas B in an ALD cycle, Gas B is flowed into plenum 610 through first and second ports of first valve 618, first and second gas lines 620, 622, fourth passage 623, third gas line 625, if present, inlet 614, and first passage 616. If second and third valves 624, 626 are not used, residual Gas A in plenum 610 is diverted through passages 619, 621 and outlets 615, 617 (i.e., through gas bypass paths 619, 615, 621, 617) into processing chamber 601 and further to the exhaust facility via the chamber exhaust. Alternatively, if second and third valves 624, 626 are used, the first ports (and second ports, if closed) of second and third valves 624, 626 are opened to connect plenum 610 to gas bypass paths 619, 628, 624, 621, 630, 626. Residual gas A in plenum 610 is diverted through gas bypass paths 619, 628, 624, 621, 630, 626 into the exhaust facility via the chamber exhaust port.

[0136] During the transition, gas bypass paths 619, 615, 621, 617 (or gas bypass paths 619, 628, 624, 621, 630, 626) divert gas flow from the process volume to the chamber exhaust and represent a less restrictive path to the chamber exhaust compared to the hole pattern of the showerhead 600. Gas B is then dispersed from the plenum 610 toward the substrate 606 via an outlet in the faceplate 612. Alternatively, if second and third valves 624, 626 are used, the first ports (and optionally the second ports) of the second and third valves 624, 626 are closed and Gas B is dispersed from the plenum 610 toward the substrate 606 via an outlet in the faceplate 612. This process is repeated when transitioning from Gas B to Gas A.

[0137] During each transition, gas bypass paths 619, 615, 621, 617 (or gas bypass paths 619, 628, 624, 621, 630, 626) provide a path for gases in plenum 610 to exit showerhead 600 so that the path does not go to substrate 606 (i.e., does not go to the process volume between showerhead 600 and substrate 606). Gas bypass paths 619, 615, 621, 617 (or gas bypass paths 619, 628, 624, 621, 630, 626) allow gases in plenum 610 to exit downstream from plenum 610 relatively quickly, representing minimal dead legs between outlets 615, 617 and the process volume, or between second and third valves 624, 626 and the process volume, leaving only the volume of the holes in faceplate 612 as dead legs, rather than the entire showerhead 600.

[0138] 6 illustrates a method 650 for operating the showerhead shown in FIGS. 3A-5B and providing a gas bypass path downstream of the showerhead, according to the present disclosure. For example, method 650 can be performed by a controller (e.g., element 160 shown in FIG. 1A ) during an ALD process performed in a processing chamber (e.g., element 102 shown in FIG. 1A ) using any of the showerheads shown in FIGS. 3A-5B . In the following description, the term control refers to operations performed by the controller.

[0139] In 652, the control opens an inlet valve (e.g., ALD valve 356, 418, 456, 518, 556, or 618 shown in FIGS. 3A-5B) and closes one or more outlet valves (e.g., elements 372, 424 and 426, 472, 524 and 526, 572, or 624 and 626 shown in FIGS. 3A-5B). In 654, the control supplies a gas (e.g., Gas A) via the inlet valve to an inlet of a showerhead (e.g., elements 360, 414, 460, 514, 560, or 614 shown in FIGS. 3A-5B).

[0140] In 656, control determines whether the time to switch gas supplies has arrived (i.e., transition from supplying Gas A to supplying Gas B). Control returns to 654 if the time to switch gas supplies has not arrived. Control proceeds to 658 if the time to switch gas supplies has arrived.

[0141] At 658, control opens one or more outlet valves. If the configuration shown in FIG. 5B does not include valves 624, 624, control skips this step and proceeds to 660. At 660, control switches the gas supply to the showerhead inlet through the inlet valve (i.e., supplies Gas B). At 662, control closes one or more outlet valves after a predetermined time has elapsed since opening the one or more valves. Again, if the configuration shown in FIG. 5B does not include valves 624, 624, control skips this step and proceeds to 664.

[0142] In 664, control determines whether the process (e.g., ALD) being performed in the processing chamber using the showerhead is complete. Control returns to 656 to continue switching the gases supplied to the showerhead until the process is complete. Control terminates when the process is complete. By controlling one or more output valves located downstream of the showerhead during gas transitions in this manner, method 650 provides one or more gas bypass paths downstream of the showerhead, as described above.

[0143] The foregoing description is merely exemplary in nature and is in no way intended to limit the disclosure, its application, or uses. The broad teachings of the disclosure can be embodied in a variety of forms. Accordingly, while the disclosure includes specific examples, the true scope of the disclosure should not be limited to such examples, as other modifications will become apparent upon review of the drawings, the specification, and the following claims.

[0144] It should be understood that one or more steps in a method may be performed in a different order (or simultaneously) without altering the principles of the present disclosure. Moreover, while each embodiment is described above as having certain features, any one or more of these features described with respect to any embodiment of the present disclosure may be implemented in other embodiments and / or combined with any features of other embodiments (even if such combination is not explicitly described). In other words, the described embodiments are not mutually exclusive, and it is within the scope of the present disclosure to interchange one or more embodiments.

[0145] Spatial and functional relationships between elements (e.g., modules, circuit elements, semiconductor layers, etc.) are described using various terms such as "connected," "engaged," "coupled," "adjacent," "next to," "on," "above," "below," and "disposed." Also, when a relationship between a first element and a second element is described in the above disclosure, unless expressly described as "direct," the relationship may be a direct relationship where no other intervening elements exist between the first element and the second element, or an indirect relationship where one or more intervening elements (spatial or functional) exist between the first element and the second element. As used herein, the phrase "at least one of A, B, and C" should be interpreted in the sense of a logical (A or B or C) using a non-exclusive logical OR, and not in the sense of "at least one of A, at least one of B, and at least one of C."

[0146] In some embodiments, the controller is part of a system, and such a system may be part of the examples described above. Such a system may include semiconductor processing equipment, including one or more processing tools, one or more chambers, one or more processing platforms, and / or specific processing components (e.g., pedestals, gas flow systems, etc.). These systems may be integrated with electronics for controlling system operation before, during, and after processing of semiconductor wafers or substrates. Such electronics may be referred to as a "controller" and may control various components or subcomponents of one or more systems.

[0147] The controller may be programmed to control any of the processes disclosed herein depending on the processing requirements and / or type of system, including process gas delivery, temperature settings (e.g., heating and / or cooling), pressure settings, vacuum settings, power settings, radio frequency (RF) generator settings, RF matching circuit settings, frequency settings, flow rate settings, fluid delivery settings, position and motion settings, wafer transfer to and from tools and other transport tools connected or interfaced with a particular system, and / or wafer transfer to and from load locks.

[0148] Broadly, a controller may be defined as an electronic device having various integrated circuits, logic, memory, and / or software that receives instructions, issues instructions, controls operations, enables cleaning operations, enables endpoint measurements, etc. Integrated circuits may include chips in the form of firmware that store program instructions, digital signal processors (DSPs), chips defined as application specific integrated circuits (ASICs), and / or one or more microprocessors, i.e., microcontrollers, that execute program instructions (e.g., software).

[0149] Program instructions may be instructions communicated to the controller in the form of various individual settings (or program files) that define operational parameters for performing a particular process on or for a semiconductor wafer or for a system. The operational parameters may, in some embodiments, be part of a recipe defined by a process engineer to accomplish one or more processing steps in the fabrication of one or more layers, materials, metals, oxides, silicon, silicon dioxide, surfaces, circuits, and / or wafer dies.

[0150] The controller, in some embodiments, may be part of, coupled to, or a combination of a computer that is integrated with, coupled to, or otherwise networked to the system. For example, the controller may be in the "cloud" or all or part of a fab host computer system, allowing remote access of wafer processing. The computer may provide remote access to the system to monitor the current progress of a fabrication operation, review the history of past fabrication operations, review trends or performance criteria from multiple fabrication operations, modify parameters of a current process, set up processing steps following the current process, or initiate a new process.

[0151] In some examples, a remote computer (e.g., a server) can provide a process recipe to the system over a network. Such a network may include a local network or the Internet. The remote computer may include a user interface that allows entry or programming of parameters and / or settings, which are then communicated from the remote computer to the system. In some examples, the controller receives instructions in the form of data. Such data identifies parameters for each processing step to be performed during one or more operations. It should be understood that the parameters may be specific to the type of process being performed and the type of tool the controller is configured to interface with or control.

[0152] Thus, as discussed above, the controller may be distributed, for example, by having one or more individual controllers networked together and cooperating toward a common purpose (such as the processes and controls described herein). An example of a distributed controller for such a purpose would include one or more integrated circuits on the chamber that communicate with one or more integrated circuits located remotely (e.g., at the platform level or as part of a remote computer) and coupled to control the processes in the chamber.

[0153] Exemplary systems may include, but are not limited to, a plasma etch chamber or module, a deposition chamber or module, a spin rinse chamber or module, a metal plating chamber or module, a cleaning chamber or module, a bevel edge etch chamber or module, a physical vapor deposition (PVD) chamber or module, a chemical vapor deposition (CVD) chamber or module, an atomic layer deposition (ALD) chamber or module, an atomic layer etch (ALE) chamber or module, an ion implantation chamber or module, a tracking chamber or module, and any other semiconductor processing system that may be associated with or used in the fabrication and / or manufacturing of semiconductor wafers.

[0154] As noted above, depending on one or more process steps being performed by the tool, the controller may communicate with one or more other tool circuits or modules, other tool components, cluster tools, other tool interfaces, adjacent tools, nearby tools, tools located throughout the factory, a main computer, another controller, or tools used in material transport to and from tool locations and / or load ports in a semiconductor fabrication factory. The present disclosure includes the following application examples: [Application example 1] 1. A showerhead for a processing chamber, comprising: a body having an upper surface, a lower surface, and a side surface defining a plenum; a plurality of through-holes in the lower surface of the body, the through-holes being in fluid communication with the plenum and the processing chamber; an inlet provided on one of the top surface and the side surface of the body; a first passageway in the body, the first passageway connecting the inlet to the plenum; an outlet provided on one of the top surface and the side surface of the body; a second passageway in the body, the second passageway connecting the outlet to the plenum; Equipped with a shower head. [Application example 2] The shower head according to Application Example 1, The showerhead, wherein the outlet is downstream relative to and in fluid communication with the inlet. [Application example 3] The shower head according to Application Example 1, The inlet and the outlet are located at opposite ends of the showerhead. [Application example 4] The shower head according to Application Example 1, The showerhead, wherein the inlet and the outlet are connected to opposite ends of the plenum. [Application example 5] The shower head according to Application Example 1, The showerhead, wherein the inlet and the outlet are located at opposite ends of the showerhead and connected to opposite ends of the plenum. [Application Example 6] The shower head according to Application Example 1, first and second valves connected to the inlet and the outlet, respectively; Equipped with the first valve is connected to a gas source; the second valve is connected to an exhaust port of the processing chamber; system. [Application Example 7] The system according to Application Example 6, closing the second valve and opening the first valve to supply a first gas from the gas source to the inlet; opening the second valve when a second gas is subsequently supplied from the gas source through the first valve to the inlet in place of the first gas; After a predetermined time, the second valve is closed. The system further comprises a controller configured to: [Application Example 8] The shower head according to Application Example 1, the side surfaces extend vertically toward a bottom of the processing chamber; The outlet is located at the bottom end of the side. Shower head. [Application Example 9] The showerhead according to Application Example 8, The showerhead, wherein the bottom end of the side extends beyond at least a portion of a pedestal disposed within the processing chamber. [Application Example 10] The shower head according to Application Example 8, first and second valves connected to the inlet and the outlet, respectively; Equipped with the first valve is connected to a gas source; the second valve is in fluid communication with an exhaust outlet of the processing chamber; system. [Application Example 11] The system according to Application Example 10, closing the second valve and opening the first valve to supply a first gas from the gas source to the inlet; opening the second valve when a second gas is subsequently supplied from the gas source through the first valve to the inlet in place of the first gas; After a predetermined time, the second valve is closed. The system further comprises a controller configured to: [Application Example 12] The shower head according to Application Example 1, The showerhead, wherein the lower surface is attached to a sidewall of the processing chamber. [Application Example 13] The showerhead according to Application Example 12, The showerhead, wherein the outlet is located at a bottom end of the sidewall. [Application Example 14] The shower head according to Application Example 13, first and second valves connected to the inlet and the outlet, respectively; Equipped with the first valve is connected to a gas source; the second valve is in fluid communication with an exhaust port of the processing chamber located at the bottom of the processing chamber; system. [Application Example 15] The system according to Application Example 14, closing the second valve and opening the first valve to supply a first gas from the gas source to the inlet; opening the second valve when a second gas is subsequently supplied from the gas source through the first valve to the inlet in place of the first gas; After a predetermined time, the second valve is closed. The system further comprises a controller configured to: [Application Example 16] The shower head according to Application Example 1, The showerhead is attached to a top plate of the processing chamber and has a diameter larger than a pedestal disposed within the processing chamber. [Application Example 17] The shower head according to Application Example 16, first and second valves disposed on the top plate and connected to the inlet and the outlet, respectively; Equipped with the first valve is connected to a gas source; the second valve is connected to an exhaust port of the processing chamber; system. [Application Example 18] The system according to Application Example 17, closing the second valve and opening the first valve to supply a first gas from the gas source to the inlet; opening the second valve when a second gas is subsequently supplied from the gas source through the first valve to the inlet in place of the first gas; After a predetermined time, the second valve is closed. The system further comprises a controller configured to: [Application Example 19] The shower head according to Application Example 16, a first valve disposed on the top plate; Equipped with the first valve is connected to the inlet and to a gas source; The outlets are located around the periphery of the showerhead. system. [Application Example 20] The system according to Application Example 19, a second valve connected to the outlet Furthermore, the second valve is in fluid communication with an exhaust port of the processing chamber located at the bottom of the processing chamber; system. [Application Example 21] The system according to Application Example 20, closing the second valve and opening the first valve to supply a first gas from the gas source to the inlet; opening the second valve when a second gas is subsequently supplied from the gas source through the first valve to the inlet in place of the first gas; After a predetermined time, the second valve is closed. The system further comprises a controller configured to:

Claims

1. A system comprising:

1. A showerhead for a processing chamber, comprising: a body having an upper surface, a lower surface, and a side surface defining a plenum; a plurality of through-holes in the lower surface of the body, the through-holes being in fluid communication with the plenum and the processing chamber; an inlet provided on one of the top surface and the side surface of the body; a first passageway in the body, the first passageway connecting the inlet to the plenum; an outlet provided on one of the top surface and the side surface of the body; a second passageway in the body, the second passageway connecting the outlet to the plenum; a shower head comprising: first and second valves connected to the inlet and the outlet, respectively; Equipped with the first valve is connected to a gas source; the second valve is connected to an exhaust port of the processing chamber; moreover, closing the second valve and opening the first valve to supply a first gas from the gas source to the inlet; opening the second valve when a second gas is subsequently supplied from the gas source through the first valve to the inlet in place of the first gas; After a predetermined time, the second valve is closed. A controller configured as follows: A system comprising:

2. 10. The system of claim 1, The outlet is downstream relative to and in fluid communication with the inlet.

3. 10. The system of claim 1, The inlet and the outlet are located at opposite ends of the showerhead.

4. 10. The system of claim 1, the inlet and the outlet are connected to opposite ends of the plenum.

5. 10. The system of claim 1, The system wherein the inlet and the outlet are located at opposite ends of the showerhead and connected to opposite ends of the plenum.

6. A showerhead for a processing chamber, comprising: a body having an upper surface, a lower surface, and a side surface defining a plenum; a plurality of through-holes in the lower surface of the body, the through-holes being in fluid communication with the plenum and the processing chamber; an inlet provided on one of the top surface and the side surface of the body; a first passageway in the body, the first passageway connecting the inlet to the plenum; an outlet provided on one of the top surface and the side surface of the body; a second passageway in the body, the second passageway connecting the outlet to the plenum; Equipped with the side surfaces extend vertically toward a bottom of the processing chamber; The outlet is located at the bottom end of the side. Shower head.

7. 7. The showerhead of claim 6, The showerhead, wherein the bottom end of the side extends beyond at least a portion of a pedestal disposed within the processing chamber.

8. The showerhead according to claim 6 ; first and second valves connected to the inlet and the outlet, respectively; Equipped with the first valve is connected to a gas source; the second valve is in fluid communication with an exhaust outlet of the processing chamber; system.

9. 9. The system of claim 8, closing the second valve and opening the first valve to supply a first gas from the gas source to the inlet; opening the second valve when a second gas is subsequently supplied from the gas source through the first valve to the inlet in place of the first gas; After a predetermined time, the second valve is closed. The system further comprises a controller configured to:

10. A showerhead for a processing chamber, comprising: a body having an upper surface, a lower surface, and a side surface defining a plenum; a plurality of through-holes in the lower surface of the body, the through-holes being in fluid communication with the plenum and the processing chamber; an inlet provided on one of the top surface and the side surface of the body; a first passageway in the body, the first passageway connecting the inlet to the plenum; an outlet provided on one of the top surface and the side surface of the body; a second passageway in the body, the second passageway connecting the outlet to the plenum; Equipped with the lower surface is attached to a sidewall of the processing chamber; The showerhead, wherein the outlet is located at a bottom end of the sidewall.

11. The showerhead of claim 10; first and second valves connected to the inlet and the outlet, respectively; Equipped with the first valve is connected to a gas source; the second valve is in fluid communication with an exhaust port of the processing chamber located at the bottom of the processing chamber; system.

12. 12. The system of claim 11, closing the second valve and opening the first valve to supply a first gas from the gas source to the inlet; opening the second valve when a second gas is subsequently supplied from the gas source through the first valve to the inlet in place of the first gas; After a predetermined time, the second valve is closed. The system further comprises a controller configured to:

13. A system comprising:

1. A showerhead for a processing chamber, comprising: a body having an upper surface, a lower surface, and a side surface defining a plenum; a plurality of through-holes in the lower surface of the body, the through-holes being in fluid communication with the plenum and the processing chamber; an inlet provided on one of the top surface and the side surface of the body; a first passageway in the body, the first passageway connecting the inlet to the plenum; an outlet provided on one of the top surface and the side surface of the body; a second passageway in the body, the second passageway connecting the outlet to the plenum; Equipped with the showerhead is attached to a top plate of the processing chamber and has a diameter larger than a pedestal disposed within the processing chamber. A shower head and first and second valves disposed on the top plate and connected to the inlet and the outlet, respectively; Equipped with the first valve is connected to a gas source; the second valve is connected to an exhaust port of the processing chamber; system.

14. 14. The system of claim 13, closing the second valve and opening the first valve to supply a first gas from the gas source to the inlet; opening the second valve when a second gas is subsequently supplied from the gas source through the first valve to the inlet in place of the first gas; After a predetermined time, the second valve is closed. The system further comprises a controller configured to:

15. A system comprising:

1. A showerhead for a processing chamber, comprising: a body having an upper surface, a lower surface, and a side surface defining a plenum; a plurality of through-holes in the lower surface of the body, the through-holes being in fluid communication with the plenum and the processing chamber; an inlet provided on one of the top surface and the side surface of the body; a first passageway in the body, the first passageway connecting the inlet to the plenum; an outlet provided on one of the top surface and the side surface of the body; a second passageway in the body, the second passageway connecting the outlet to the plenum; Equipped with the showerhead is attached to a top plate of the processing chamber and has a diameter larger than a pedestal disposed within the processing chamber. A shower head and a first valve disposed on the top plate; Equipped with the first valve is connected to the inlet and to a gas source; The outlets are located around the periphery of the showerhead. system.

16. 16. The system of claim 15, a second valve connected to the outlet Furthermore, the second valve is in fluid communication with an exhaust port of the processing chamber located at the bottom of the processing chamber; system.

17. 17. The system of claim 16, closing the second valve and opening the first valve to supply a first gas from the gas source to the inlet; opening the second valve when a second gas is subsequently supplied from the gas source through the first valve to the inlet in place of the first gas; After a predetermined time, the second valve is closed. The system further comprises a controller configured to:

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