High-speed gas exchange apparatus, system, and method
The gas distribution system with a switching valve and proportional flow control valves addresses the inefficiencies of conventional systems by stabilizing gas flow rapidly and reducing gas consumption, improving process uniformity and efficiency in semiconductor processing.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- APPLIED MATERIALS INC
- Filing Date
- 2026-02-09
- Publication Date
- 2026-05-26
AI Technical Summary
Existing gas supply systems for semiconductor processing chambers require multiple dedicated gas sticks, leading to increased gas consumption and high costs, and conventional methods for stabilizing gas flow result in long settling times, affecting process uniformity and efficiency.
A gas distribution system with a common housing containing two reservoirs and a switching valve that alternates between them, coupled with proportional flow control valves, allows for rapid gas switching and stable gas supply without relying on foreline dumping, reducing the need for dedicated gas sticks and minimizing gas consumption.
The system achieves stable, high-speed gas flow stabilization with minimal settling time, enhancing process uniformity and throughput while reducing gas consumption and hardware costs, enabling faster cycling between gases and a wider process window.
Smart Images
Figure 2026086631000001_ABST
Abstract
Description
Technical Field
[0001]
[0001] Embodiments of the present disclosure generally relate to substrate processing systems. In particular, embodiments of the present disclosure relate to methods and apparatuses for providing process gases to a substrate processing system.
Background Art
[0002]
[0002] The formation of semiconductor devices generally takes place within a substrate processing platform that includes multiple chambers. In some cases, a multi-chamber processing platform or cluster tool is used to sequentially perform two or more processes on a single substrate within a controlled environment.
[0003]
[0003] During the manufacturing of semiconductor devices, a stable process gas flow into the processing chamber is desired to provide process uniformity and minimize processing defects. Generally, the flow rate of the process gas increases over time from zero to a steady state by opening the gas delivery valve. In some processes, the duration of the gas flow until it settles to a steady state accounts for a significant portion of the total gas flow time. In such processes, a relatively long settling time leads to undesirable processing results. To reduce, and in some cases eliminate, the settling time, some gas supply systems maintain a steady process flow by diverting the entire flow into the chamber foreline when flow into the chamber is not needed. When needed, the entire flow is quickly switched from the foreline to the processing chamber with little to no settling time, resulting in improved process uniformity and processing results. Dividing the process gas flow between the foreline and the processing chamber has proven to be an effective technique for obtaining desired process results, but it utilizes a large amount of process gas. Furthermore, the supply hardware for providing the precursor flow is expensive and often requires dedicated gas sticks for supplying process gas to different areas of the processing chamber, such as the inner and outer regions of the showerhead. The need for multiple dedicated gas sticks only leads to the further undesirable consequence of increased gas consumption.
[0004]
[0004] Therefore, there is a need to supply process gas to the processing chamber using an optimized amount of gas without using multiple dedicated gas sticks. [Overview of the project]
[0005]
[0005] In some embodiments, a gas distribution device is provided having a first reservoir having a first upstream end and a first downstream end, and a second reservoir having a second upstream end and a second downstream end. A reservoir switching valve is in fluid communication with the first downstream end of the first reservoir and the second downstream end of the second reservoir. The reservoir switching valve is operable to selectively connect the first reservoir to the outlet of the reservoir switching valve when in a first state, and to selectively connect the second reservoir to the outlet of the reservoir switching valve when in a second state. A plurality of proportional flow control valves are provided, each having an inlet connected in parallel to the outlet of the reservoir switching valve. The plurality of proportional flow control valves have outlets configured to supply gas to a processing chamber.
[0006]
[0006] In some embodiments, a semiconductor processing system is provided which has a process chamber having a process space for processing a substrate. The process chamber has a first process gas inlet and a second process gas inlet. The system includes a gas distribution assembly which has a first reservoir having a first upstream end and a first downstream end, and a second reservoir having a second upstream end and a second downstream end. A reservoir switching valve is in fluid communication with the first downstream end of the first reservoir and the second downstream end of the second reservoir. The reservoir switching valve is operable to selectively couple the first reservoir to the outlet of the reservoir switching valve when in a first state, and to selectively couple the second reservoir to the outlet of the reservoir switching valve when in a second state. The first and second proportional flow control valves have inlets connected in parallel to the outlet of the reservoir switching valve, the first proportional flow control valve has an outlet connected to the first inlet of the processing chamber, and the second proportional flow control valve has an outlet connected to the second inlet of the processing chamber.
[0007]
[0007] In some embodiments, a method is provided for supplying a gas to the process space of a process chamber. The method includes supplying a first process gas from a first reservoir to the process space through a reservoir switching valve in a first state. Supplying the first process gas to the process space includes maintaining a first gas pressure range in the first reservoir and controlling the flow of the first process gas from the first reservoir to one or more areas of the process space using a plurality of proportional flow control valves located upstream of the process space. The reservoir switching valve is switched to a second state. A second process gas is supplied to the process space through a reservoir switching valve in a second state. The second process gas is supplied from a second reservoir. Supplying the second process gas includes maintaining a second gas pressure range in the second reservoir and controlling the flow of the second process gas from the second reservoir to one or more areas of the process space using a plurality of proportional flow control valves located upstream of the process space.
[0008]
[0008] To enable a detailed understanding of the features of the present disclosure described above, a more specific description of the present disclosure, which has been briefly summarized above, can be obtained by reference to embodiments, some of which are illustrated in the accompanying drawings. However, it should be noted that the accompanying drawings show only exemplary embodiments and should not be considered to limit the scope of the present disclosure, and other equally valid embodiments may also be permitted. [Brief explanation of the drawing]
[0009] [Figure 1]
[0009] A schematic diagram of a gas distribution system according to an embodiment of the present disclosure is shown. [Figure 2]
[0010] This diagram shows a schematic representation of a gas distribution system used to distribute gas to multiple regions within a single process chamber. [Figure 3]
[0011] A flowchart of the method according to the embodiments of this disclosure is shown. [Modes for carrying out the invention]
[0010]
[0012] For ease of understanding, the same reference numerals were used to indicate identical elements common to the figures where possible. Elements and features of one embodiment are considered to be usefully incorporated into several other embodiments without additional description.
[0011]
[0013] Multiple embodiments of this disclosure provide substrate processing systems having a stable process gas supply that improves throughput and enhances processing efficiency. One or more embodiments of this disclosure are described in relation to plasma etching processing chambers. However, the gas distribution system may be used in other types of processing chambers, such as chemical vapor deposition chambers, atomic layer deposition chambers, injection chambers, or other processing chambers. In particular, the gas distribution system described herein provides very high-speed flow stabilization. Thereafter, the flow may be turned on or switched between gases in a manner that causes little to no flow rate settling time. This results in a very stable gas supply that promotes process uniformity and defect deduction. Furthermore, very high-speed flow stabilization also enables faster cycling between gases, thus enabling a larger process window and a wider variety of processes. Moreover, since the gas distribution system does not rely on dumping (releasing) the process gas flow into the foreline to enable fast flow stabilization as done in conventional systems, it favorably reduces the amount and cost of process gas required to run cyclic processes such as trench etching processes. Furthermore, the gas distribution system disclosed herein further reduces the cost of expensive process gas supply hardware by eliminating the need for dedicated gas sticks in conventional processing chambers to supply process gas to different processing areas of the processing chamber.
[0012]
[0014] Figure 1 shows a schematic diagram of a gas distribution system 100. The gas distribution system 100 includes a common housing 108 for distributing gas to multiple process areas 101. The processing areas 101 are either separate processing chambers or separate process areas within a single process chamber. Figure 2 shows a gas distribution system used to distribute gas to multiple areas within a single process chamber 203 according to one embodiment. Although Figure 1 shows three process areas 101, more or fewer process areas 101 may also be used in the gas distribution system 100 of this disclosure.
[0013]
[0015] The common housing 108 includes two or more gas reservoirs (e.g., a first gas reservoir 114 and a second gas reservoir 124). In some embodiments, which may be combined with other embodiments described herein, the common housing may or may not be temperature-controlled. Although the first and second reservoirs 114, 124 are depicted within the common housing 108, the gas distribution system 100 described herein may also include embodiments that do not have a common housing 108. In some embodiments, which may be combined with other embodiments described herein, the first and second reservoirs 114, 124 are located in close proximity to and coupled to a plurality of process regions 101. The first gas reservoir 114 includes a first upstream end 113 and a first downstream end 115. The second gas reservoir 124 includes a second upstream end 123 and a second downstream end 125. Pressure gauges (e.g., a first pressure gauge 116 for the first reservoir 114, a second pressure gauge 126 for the second reservoir 124) are coupled to the corresponding reservoirs and can measure the pressure in the corresponding reservoirs. In some embodiments that can be combined with other embodiments described herein, each reservoir includes two or more pressure gauges configured to measure the pressure at different points between the upstream end (e.g., 113, 123) and the downstream end (e.g., 115, 125) of each reservoir.
[0014]
[0016] One or more regulators (e.g., a first regulator 110 for the first reservoir 114) are coupled to the first upstream end 113 of the first reservoir 114, and one or more regulators (e.g., a second regulator 120 for the second reservoir 124) are coupled to the second upstream end 123 of the second reservoir 124. Each regulator (110, 120) is any suitable gas regulator or any suitable mass flow controller known in the art. Each regulator provides supply pressure (or input pressure) to each of the first and second reservoirs (114, 124). The regulators can be any mechanically or electrically controlled proportional pressure control components. Each regulator (110, 120) is coupled to the corresponding filling valve. The corresponding filling valves are coupled to the corresponding reservoirs (e.g., a first filling valve 112 for a first reservoir 114, a second filling valve 122 for a second reservoir 124). Each filling valve 112, 122 is either fully open or fully closed to allow gas to flow through or to prevent gas from flowing through. Alternatively, each filling valve 112, 122 is a variable-open valve that allows adjustment of the flow profile through the valve. Each filling valve 112, 122 is selected from fast-acting valves, solenoid valves, and piezo valves. The filling valves 112, 122 are fast-acting valves that can transition between positions (e.g., open / closed) within 50 milliseconds, e.g., within 40 milliseconds, or within 30 milliseconds, or within 10 to 20 milliseconds. In some embodiments that may be combined with other embodiments described herein, the filling valves 112, 122 are gas-operated normally closed (NC) fast-acting valves that engage when the reservoir is within about 90% of the pressure setpoint and are configured to pulse supply at intervals of about 100 ms or less until the pressure in the reservoir is within an acceptable range. The first regulator 110 and the first filling valve 112 are operable to maintain the pressure in the first reservoir 114 within a substantially constant pressure range, and the second regulator 120 and the second filling valve 122 are operable to maintain the pressure in the second reservoir 124 within a substantially constant pressure range.
[0015]
[0017] Regulators 110, 120 and filling valves 112, 122 are coupled to the first gas source 109a and the second gas source 109b via inlet lines. Each process gas from each gas source is used to fill the corresponding reservoirs 114, 124, exit the corresponding reservoirs, and flow to the reservoir switching valve 134. The switching valve 134 is one or more valve clusters, such as a three-way valve, configured to switch from a first gas from the first reservoir 114 to a second gas from the second reservoir 124, and to release each of the first and second gases downstream. Although the switching valve 134 is depicted as a three-way valve in the drawings, several other embodiments, such as one or more valve clusters, are conceivable for systems with three or more reservoirs. The reservoir switching valve is in fluid communication with the first downstream end of the first reservoir and the second downstream end of the second reservoir. During operation, the reservoir switching valve 134 can be operated to selectively connect the first reservoir to the outlet 135 of the reservoir switching valve 134 when it is in a first state. When the reservoir switching valve 134 is in a second state, it can be operated to selectively connect the second reservoir to the outlet 135 of the reservoir switching valve 134.
[0016]
[0018] Conventional gas distribution assemblies do not use switching valves downstream of the distribution lines. Instead, conventional gas distribution assemblies use multiple distribution lines from each gas source, with each distribution line corresponding to a different process station or process area. Conventional distribution assemblies continuously flow gas that is branched to either a foreline 138 or a high-speed pulse supply valve that pulses gas into the process space. It has been found that the total number of distribution lines used in the process can be minimized by incorporating a switching valve 134 that can switch between a first reservoir 114 and a second reservoir 124. Instead, the switching valve 134 alternately switches between the first and second process gases according to the process recipe, and the gas flows to multiple proportional flow control valves (140a, 140b, 140c, etc.). The multiple proportional flow control valves have inlets coupled in parallel to the outlets of the reservoir switching valve 134.
[0017]
[0019] A diverter valve 136 is positioned between the switching valve 134 and the proportional flow control valves 140a, 140b, and 140c. The diverter valve 136 is used to purge gas from each of the reservoirs into the foreline 138. The diverter valve 136 can also be operated to direct the gas flow to each of the multiple proportional flow control valves (e.g., 140a, 140b, and 140c) into each process region 101. The multiple proportional flow control valves have inlets coupled in parallel to the outlet of the diverter valve 136.
[0018]
[0020] Each of the proportional flow control valves is coupled to a corresponding process region 101. Each of the multiple proportional flow control valves (e.g., 140a, 140b, 140c) can divide the gas flow between each process region 101. Each of the multiple proportional flow control valves (e.g., 140a, 140b, 140c) is an electrically actuated piezoelectric flow control valve (e.g., a piezo valve). Each of the multiple proportional flow control valves is coupled to a heater. Downstream of each proportional flow control valve are normally open solenoid valves (NO valves), such as gas-pressure-operated valves 142a, 142b, 142c. The gas-pressure-operated valves are used to regulate the gas flow through them and are used in conjunction with pressure gauges 144a, 144b, 144c.
[0019]
[0021] The gas distribution system 100 includes a controller 190. The controller 190 is coupled to various components of the gas distribution system 100 to control their operation. The controller 190 may be a single controller controlling the system, or multiple controllers controlling individual parts of the system. In some embodiments, each of the proportional flow control valves is communicatively coupled to the controller 190. The controller 190 controls the flow ratio between the proportional flow control valves 142a, 142b, and 142c.
[0020]
[0022] In some embodiments that may be combined with other embodiments described herein, the controller 190 includes a central processing unit (CPU) 192, memory 194, and support circuitry 196. The controller 190 controls the gas distribution system 100 either directly or via a computer (or controller) associated with a particular process chamber and / or support system component. The controller 190 is one or any form of a general-purpose computer processor used in industrial settings to control various chambers and subprocessors. The controller's memory 194 or computer-readable medium is one or more readily available memories, such as random access memory (RAM), read-only memory (ROM), floppy disks, hard disks, optical storage media (e.g., compact discs or digital video discs), flash drives, or any other form of local or remote digital storage. The support circuitry 196 is coupled to the CPU 192 to support the processor in a conventional manner. These circuits include caches, power supplies, clock circuits, input / output circuits, and subsystems, etc. One or more processes are stored in memory as software routines that are executed or invoked to control the operation of the system or individual components in the manner described herein. The controller 190 includes one or more configurations that include any commands or functions for controlling flow rates, gas valves, gas sources, or other processes for performing various configurations.
[0021]
[0023] The controller 190 is connected to one or more of the regulators 110, 120, filling valves 112, 122, switching valve 134, diverter valve 136, proportional flow control valves 140a, 140b, 140c, or gas pressure operated valves 142a, 142b, 142c. The controller 190 has one or more configurations. In some embodiments that can be combined with other embodiments described herein, the controller 190 has a configuration for opening and closing one or more of the filling valves 112, 122. In some embodiments that can be combined with other embodiments described herein, the controller 190 has a configuration for monitoring pressure using one or more of the pressure gauges 116, 126, 144a, 144b, 144c.
[0022]
[0024] The gas distribution system 100 is suitable for several different processes, but one particular application is through-silicon via (TSV) etching. This is an application that uses a low-frequency bias and a low-temperature environment to form deep trenches in a silicon substrate. One type of etching system is in situ plasma etching, in which trenches are formed by repeatedly and alternately removing and depositing material on the substrate within a single reactor having removal plasma and deposition plasma. Another type of etching system is remote plasma etching, in which trenches are formed using plasma generated in a remote reactor before being introduced onto the substrate located in a primary reactor (e.g., process chamber 203 shown in Figure 2). Substrate processing involves alternately depositing and etching a film on the substrate by continuously supplying deposition gas and etching gas. Only two gas sources 109a and 109b are depicted in Figures 1 and 2, but alternative or additional gas sources are also possible. In this method, an etching gas is provided in a series of pulses to incrementally etch trenches or other features into the substrate, while a deposition gas is provided between etching pulses of the etching gas to coat and protect the sidewalls of the trenches or other features being etched into the substrate.
[0023]
[0025] Figure 2 depicts a reactor 200 having a process chamber 203 and a gas distribution system 100 that distributes gas to multiple regions within the process space 202 of the process chamber 203. The process chamber 203 includes a lid 204, a power supply 215 and matching network 217, a bias power supply 220 and matching network 221, an electrostatic chuck 240, and the gas distribution system 100. Proportional flow control valves 140a and 140b of the gas distribution system 100 direct the gas to a nozzle assembly 207 coupled to the lid 204 of the process chamber 203. Proportional flow control valve 140a is coupled to the edge nozzle of the nozzle assembly 207 via a first gas inlet 232, and the edge nozzle directs the gas to the edge regions of the process space 202. Proportional flow control valve 140b is coupled to the central nozzle of the nozzle assembly 207 via a second gas inlet 234, and the central nozzle directs the gas to the central region of the process space 202. The first gas inlet 232 is located outside the second gas inlet 234 with respect to the vertical centerline of the processing chamber. While the drawing depicts the second gas inlet as being in the center of the nozzle assembly 207, other positions, such as those offset from the center, are also possible. The radial position of the second gas inlet 234 (e.g., from the centerline of the nozzle assembly 207) may be offset from the radial position of the first gas inlet 232. A proportional flow control valve 140c directs the gas to a side nozzle 205 located on the side 206 of the process chamber 203. Although three proportional flow control valves are depicted in the drawing, more or fewer proportional flow control valves are possible to direct the gas to more or less of the process space 202 for customized adjustment of the gas flow.
[0024]
[0026] A power supply 215 for generating and maintaining a plasma process is coupled to a process chamber 203 via a generator (not shown) that can take the form of one or more antennas or coils. The power supply 215 is operable to generate a radio frequency in the range of from about 12 MHz to about 13.5 MHz with a pulse supply capability, and power in the range of from about 10 watts to about 7500 watts, for example from about 300 watts to about 5000 watts, and further includes a dynamic matching network 217. The power supply 215 includes a dual tunable source such that the radio frequency is changed during an etching cycle. In some embodiments, which may be combined with other embodiments described herein, the power supply 215 includes a remote plasma source that can be attached to the process chamber 203 and generates a high level of plasma dissociation. The process chamber 203 includes in-situ source power, remote plasma source power, or a combination of both. In some embodiments, which may be combined with other embodiments described herein, the plasma is generated with remote plasma source power and transferred to the process chamber 203, and the in-situ source power 215 maintains the generated plasma within the process chamber 203. An etching cycle is performed where the power range of the power supply 215 may be increased or decreased during the etching cycle and / or pulsed during the etching cycle.
[0025]
[0027] A bias power supply 220 for applying a bias to a substrate is coupled to a process chamber 203 and a chuck 240. The bias power supply 220 is operable to generate a radio frequency of about 2 MHz having a pulse supply capability and a low power range from about 10 watts to about 500 watts, and further includes a dynamic matching network 221. The bias power supply 220 can generate a selectable radio frequency range from about 100 kHz to about 13.56 MHz having a pulse supply capability and a power range from about 10 watts to about 2000 watts. In some embodiments that can be combined with other embodiments described herein, an etching cycle includes a deposition operation and an etching operation that are periodically repeated. After the etching operation of the etching cycle, the radio frequency and / or wattage of the bias power supply 220 may be increased or decreased relative to the previous etching operation of the etching system. In one example, the bias power supply 220 is greater during the etching operation compared to the deposition operation.
[0026]
[0028] FIG. 3 shows a flow diagram of a process 300 for distributing gas according to multiple embodiments of the present disclosure. The method includes, in operation 302, supplying a first process gas from a first reservoir 114 to a process region 101 through a reservoir switching valve in a first state. The first reservoir 114 is filled using a first gas source 109a, and a first gas pressure range is maintained within the first reservoir. A first process gas flow from the first reservoir to one or more regions of the process space 202 is controlled using a plurality of proportional flow control valves disposed upstream of the process space 202.
[0027]
[0029] For etching applications, two or more gas sources may be coupled to the first reservoir 114. In addition to the etchant, one or more of oxygen, helium, and argon may be provided. In some embodiments, which may be combined with other embodiments described herein, a plasma sustaining gas such as argon is provided. In some embodiments, which may be combined with other embodiments described herein, a gas distribution assembly is configured for silicon etching, and the first process gas is an etching gas such as a fluoride-containing gas, a sulfur-containing gas, or a gas containing one or both of fluoride and sulfur. The first process gas is supplied to the process space 202 at a rate of about 10 sccm to about 3000 sccm for a predetermined duration. In some embodiments, the first process gas is an etching gas that etches a portion of the features in the substrate located in the process space 202.
[0028]
[0030] In conventional processes, a high-speed valve is switched on / off at a specific high frequency, such as a pulse, to control the amount of gas introduced into the process space 202. In the gas distribution system 100 described herein, a proportional flow control valve, such as a piezo valve, is used instead to control the amount of gas introduced into a specific area of the process space 202. Thus, the gas distribution system of this disclosure eliminates the use of valves having a pulse supply mechanism. Each proportional flow control valve is controlled by a controller 190 and uses a process time of about 0.2 seconds or more, for example, about 0.3 seconds or more, for example, about 1 to 2 seconds, or about 0.3 to about 0.5 seconds for each process operation.
[0029]
[0031] In operation 304, the gas flow is switched from the first reservoir to the second gas from the second reservoir. Specifically, the reservoir switching valve 134 is switched from the first state to the second state, thereby allowing the second gas from the second reservoir to flow through the outlet of the reservoir switching valve 134. The switching valve 134 directs the gas to a plurality of proportional flow control valves (140a, 140b, 140c). The plurality of proportional flow control valves are operable to divide the gas flow through them into predetermined ratios to the process space 202. The controller 190 is communicatively coupled to the reservoir switching valve 134 and controls the synchronous switching of the gas to predetermined time sequences of flow controller operations, such as valve timing control. The controller 190 is communicatively coupled to the plurality of proportional flow control valves 140a, 140b, 140c and to gas pressure-operated valves downstream of the proportional flow control valves for regulating the gas flow to each region of the process space 202. By adjusting the gas flow to each region of the process space 202, the processing of the substrate and the uniformity of the processing are improved. In some embodiments that may be combined with other embodiments described herein, the switching from the first reservoir 114 to the second reservoir 124 occurs substantially simultaneously with opening the first filling valve 112 to refill the partially depleted first reservoir 114. Alternatively, the filling valve 112 is opened when the first pressure gauge 116 reaches the lower limit pressure of the reservoir and / or closed when the first pressure gauge 116 reaches the upper limit pressure. In some embodiments that may be combined with other embodiments described herein, the first and second filling valves are piezo valves used to maintain the pressures of the first and second reservoirs within a predetermined range, such as between about 100 Torr and about 1000 Torr, depending on the process. Similar process control is applicable to the second reservoir to switch from the second reservoir to the first reservoir during processing.
[0030]
[0032] In operation 306, a second process gas is supplied to the process area 101 from a second reservoir 124. The second reservoir 124 is filled using a second gas source 109b. A second gas pressure range is maintained within the second reservoir. The flow of the second process gas from the second reservoir to one or more regions of the process space 202 is controlled using a plurality of proportional flow control valves located upstream of the process space 202. It is also conceivable that two or more gas sources, such as one or more of oxygen, helium, and argon, be coupled to the second reservoir 124. In some embodiments that may be combined with other embodiments described herein, the second process gas is a deposit gas, such as a polymer deposit gas (e.g., a fluoride-containing gas, a carbon-containing gas, or a gas having one or more of fluoride and carbon, such as fluorinated carbon). The second process gas is supplied to the process space 202 at a pressure of about 10 sccm to about 3000 sccm. In some embodiments, which may be combined with other embodiments described herein, a second process gas is used to deposit a protective polymer layer on the etched portion of the substrate features (e.g., etched in operation 302). Each proportional flow control valve is controlled by controller 190 and uses a process time of about 0.2 seconds or more, e.g., about 0.3 seconds or more, e.g., about 1 to 2 seconds, or about 0.3 to 0.5 seconds for each process operation.
[0031]
[0033] After supplying the second gas to the process space 202, in operation 308, the reservoir switching valve is switched from the second state to the first state. Thus, the first process gas from the first reservoir is again in fluid communication with the process space. Operations 302, 304, 306, and 308 are repeated in predetermined process cycles to form features on the substrate by periodically etching a portion of the feature, depositing a protective polymer layer on the etched portion, then etching another portion of the feature, depositing another polymer layer on the etched portion, and so on, until a desired depth is etched to form the feature. The gas distribution system 100 described herein is used to rapidly switch between gases to process the substrate, such as forming a predetermined profile on a silicon substrate placed in the process space 202.
[0032]
[0034] The high-speed gas exchange assembly described herein is useful in etching systems employing multi-step processes. The same hardware and operating scheme can also be used in other processes, such as atomic layer deposition processes, where rapid gas switching through the processing chamber 203 is required.
[0033]
[0035] The foregoing applies to a number of embodiments of the present disclosure, but other and further embodiments of the present disclosure may be devised without departing from the scope of the present disclosure, which is defined by the following claims.
Claims
1. A first reservoir having a first upstream end and a first downstream end, A second reservoir having a second upstream end and a second downstream end, A reservoir switching valve having fluid communication between the first downstream end of the first reservoir and the second downstream end of the second reservoir, wherein the valve is operable to selectively connect the first reservoir to the outlet of the reservoir switching valve when in a first state, and to selectively connect the second reservoir to the outlet of the reservoir switching valve when in a second state, and A gas distribution device comprising a plurality of proportional flow control valves, each having an inlet connected in parallel to the outlet of the reservoir switching valve, and each having an outlet configured to supply gas to a processing chamber.
2. The gas distribution device according to claim 1, wherein the first reservoir and the second reservoir are arranged in a common housing.
3. A first filling valve and a first regulator, coupled to the first upstream end of the first reservoir and operable to maintain the pressure in the first reservoir within a substantially constant pressure range, and The gas distribution device according to claim 1, further comprising a second filling valve and a second regulator, coupled to the second upstream end of the second reservoir and operable to maintain the pressure in the second reservoir within a substantially constant pressure range.
4. The gas distribution device according to claim 3, wherein the first filling valve and the second filling valve are selected from the group consisting of solenoid valves, piezo valves, fast-acting valves, and combinations thereof.
5. The gas distribution device according to claim 1, wherein each of the plurality of proportional flow control valves is a piezo valve.
6. A first pressure gauge coupled to the first reservoir, and The gas distribution device according to claim 1, further comprising a second pressure gauge coupled to the second reservoir.
7. A processing chamber including a process space for processing a substrate, the processing chamber having a first process gas inlet and a second process gas inlet, and A semiconductor processing system comprising a gas distribution assembly, wherein the gas distribution assembly is A first reservoir having a first upstream end and a first downstream end, A second reservoir having a second upstream end and a second downstream end, A reservoir switching valve having fluid communication between the first downstream end of the first reservoir and the second downstream end of the second reservoir, wherein the valve is operable to selectively connect the first reservoir to the outlet of the reservoir switching valve when in a first state, and to selectively connect the second reservoir to the outlet of the reservoir switching valve when in a second state, and A semiconductor processing system comprising a first proportional flow control valve and a second proportional flow control valve, each having an inlet connected in parallel to the outlet of the reservoir switching valve, wherein the first proportional flow control valve has an outlet connected to the first process gas inlet of the processing chamber, and the second proportional flow control valve has an outlet connected to the second process gas inlet of the processing chamber.
8. The first reservoir is in fluid communication with the etching gas source, The semiconductor processing system according to claim 7, wherein the second reservoir is in fluid communication with a deposit gas source.
9. The semiconductor processing system according to claim 7, wherein the first process gas inlet is located outside the second process gas inlet with respect to the vertical centerline of the processing chamber.
10. A first regulator coupled to the first upstream end of the first reservoir, the first regulator being operable to maintain the pressure in the first reservoir within a substantially constant pressure range, and The semiconductor processing system according to claim 9, further comprising a second regulator coupled to the second upstream end of the second reservoir, the second regulator being operable to maintain the pressure in the second reservoir within a substantially constant pressure range.
11. The semiconductor processing system according to claim 9, wherein the first process gas inlet is configured to supply the first process gas into the processing chamber through the ceiling or showerhead.
12. The semiconductor processing system according to claim 9, wherein the first process gas inlet is configured to provide the first process gas into the processing chamber by penetrating the side wall of the processing chamber.
13. The semiconductor processing system according to claim 11, wherein the first reservoir and the second reservoir are located in a common housing, and the common housing is temperature-controlled.
14. A method for supplying gas to the process space of a processing chamber, The first process gas is supplied from the first reservoir to the process space through a reservoir switching valve in the first state, Maintaining a first gas pressure range in the first reservoir, Supplying a first process gas, including controlling the flow of a first process gas from the first reservoir to one or more regions of the process space using a plurality of proportional flow control valves located upstream of the process space; Switching the reservoir switching valve to the second state, and The second process gas is supplied from the second reservoir to the process space through the reservoir switching valve in the second state, Maintaining a second gas pressure range in the second reservoir, A method for supplying a second process gas, comprising controlling the flow of a second process gas from a second reservoir to one or more regions of the process space using the plurality of proportional flow control valves located upstream of the process space.
15. Controlling the first process gas flow from the first reservoir to one or more regions of the process space is: Using the first proportional flow control valve among the plurality of proportional flow control valves, the first process gas flow to the first region among the one or more regions of the process space, and The method according to claim 14, further comprising using a second proportional flow control valve among the plurality of proportional flow control valves to control the first process gas flow to a second region among the one or more regions of the process space, wherein the first region is located outside the second region with respect to the vertical centerline of the processing chamber.
16. Controlling the first process gas flow from the first reservoir to one or more regions of the process space is: The method according to claim 15, further comprising distributing the first process gas flow from the first proportional flow control valve and a switching valve in parallel with the second proportional flow control valve.
17. Supplying the first process gas to the process space further includes flowing an etching gas through the process space, The method according to claim 16, wherein supplying the second process gas to the process space further includes flowing a deposit gas into the process space.
18. The method according to claim 14, further comprising switching the reservoir switching valve to periodically etch features in the substrate placed within the process space.
19. Switching the reservoir switching valve in order to periodically etch the features in the substrate is (a) Etching a portion of the feature with an etching gas, (b) Depositing a protective layer on the etched portion of the feature with a deposition gas, (c) The method of claim 18, further comprising periodically repeating (a) and (b) in order to form the feature.
20. The method according to claim 19, further comprising directing a gas into a foreline or the process space in a foreline valve downstream of the reservoir switching valve, wherein the foreline valve is operable to redirect the gas into the foreline or the process space.