Patent Application
20250232953
The present disclosure relates to a plasma source of a semiconductor processing system, and, more specifically, relates to a plasma source comprising a coolant leakage detection system capable of detecting the leakage of a cooling medium.
In semiconductor processing, plasma is used in many processes, including deposition of layers, etch of materials, cleaning of chambers, and abatement of effluent gases. Plasma sources have been integrated into multiple components of a semiconductor processing system. These plasma sources typically require cooling to remove heat generated during operation. These plasma sources may use a cooling system which circulates a coolant, such as water, throughout the plasma source to remove heat.
A cooling system may develop a coolant leak due to wear and tear, sputter erosion, electric arcing, and etc. The leaked coolant can be drawn into a plasma region, which is often in a vacuum. Even an introduction of a small amount of coolant into the plasma region may generate adverse effects in the processes. Current methods to detect a leak in a plasma system have relied on observations of any liquid on a floor or any adverse effects on the vacuum region. The current methods may not timely detect a leak. In addition, small leaks, such as pin holes in a cooling systems, may be difficult to be detected by the current methods.
Thus, a need exists for a plasma source with an improved system for detecting a coolant leak.
Disclosed herein are a plasma source including a cooling system capable of detecting a coolant leak, an abatement unit comprising the plasma source, and a method for detecting a coolant leak. In an example, the plasma source includes an RF generation system coupled with a cooling system. The RF generation system includes one or more electrical components operable to generate a plasma in a plasma region, the one or more electrical components comprising a hollow RF antenna. The cooling system includes a coolant channel extending through the plasma source, including the one or more electrical components of the RF generation system, and configured to flow a coolant; a first flow control device coupled to the coolant channel to control a flow of the coolant into the coolant channel and electrically isolated from the hollow RF antenna; a second flow control device coupled to the coolant channel to control a flow of the coolant out of the coolant channel; and a pressure measurement device coupled with the coolant channel to measure a pressure level of the coolant. The coolant channel includes the hollow RF antenna.
In another example, an abatement unit for abating effluent gases of a processing chamber includes a plasma source for abating the effluent gases with plasma; and a controller coupled with the plasma source and configured to control components of the plasma source. The plasma source is configured according to embodiments of the present disclosure.
In another example, the method of detecting a coolant leak of a plasma source. The plasma source includes an RF generation system coupled with a coolant leakage system. The method includes transmitting RF electrical signals along the RF generation system of the plasma source, the RF generation system comprising a hollow RF antenna; circulating a coolant within a coolant channel extending through the RF generation system, the coolant channel comprising the hollow RF antenna; measuring, by a pressure measurement device, a pressure level of the coolant; controlling, by flow control devices coupled with the coolant channel, a flow of the coolant inside the coolant channel according to the RF electrical signals; and determining, by a controller, whether a leak occurs inside the coolant channel based on the pressure level.
So that the manner in which the above recited features of the present disclosure can be understood in detail, a more particular description of the disclosure, briefly summarized above, may be had by reference to embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only exemplary embodiments and are therefore not to be considered limiting of its scope, may admit to other equally effective embodiments.
To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures. It is contemplated that elements and features of one embodiment may be beneficially incorporated in other embodiments without further recitation.
The disclosure contemplates that terms such as “couples,” “coupling,” “couple,” and “coupled” may include but are not limited to welding, fusing, melting together, interference fitting, and/or fastening such as by using bolts, threaded connections, pins, and/or screws. The disclosure contemplates that terms such as “couples,” “coupling,” “couple,” and “coupled” may include but are not limited to integrally forming. The disclosure contemplates that terms such as “couples,” “coupling,” “couple,” and “coupled” may include but are not limited to direct coupling and/or indirect coupling, such as indirect coupling through components such as links, blocks, and/or frames.
Disclosed herein are a cooling system capable of detecting a coolant leak and a plasma source including the cooling system. The cooling system includes a hollow RF antenna which can transmit RF power signals to a plasma chamber and circulate a coolant within an internal coolant channel. The coolant channel contacts external surfaces of a plasma chamber. The coolant within the coolant channel removes heat from the plasma chamber.
The cooling system includes two valves controlling the coolant flow into and out of the coolant channel. The cooling system further includes a pressure measurement device disposed between the valves and the plasma chamber. When the plasma chamber stops generating plasma, the two valves are shut off, thus isolating the coolant within the coolant channel, including the hollow RF antenna, from external influences. The pressure measurement device measures the pressure level of the isolated coolant and transmits the measured pressure level to a controller. The controller determines whether a coolant leak occurs based on the measured pressure level. As the coolant channel, including the hollow RF antenna, contains a limited amount of coolant, even a small leak, such as a leak through a pin hole, can cause a noticeable drop of the pressure level, which is detected by the pressure measurement device. Thus, the present cooling system can detect a small, early stage coolant leak and allow the plasma source and a higher level system to take timely remediation actions.
A controller of the plasma source or a higher level system may compare the measured pressure level with a predetermined threshold to determine a leak. Other methods may also be implemented to determine a leak, such as by observing a trend of the pressure levels over a period, comparing the pressure level with a history of the pressure level, or any other suitable methods. After a leak is determined, the controller may turn off the coolant system, transmit a message to an operator, or take any other mitigation and/or notification tasks.
The processing platform 104 includes a plurality of processing chambers 110, 112, 120, 128, the one or more load lock chambers 122, and a transfer chamber 136 that is coupled to the one or more load lock chamber 122. The transfer chamber 136 can be maintained under vacuum, or can be maintained at an ambient (e.g., atmospheric) pressure. Two load lock chambers 122 are shown in
In one or more embodiments, the factory interface 102 includes at least one docking station 109 and at least one factory interface robot 114 to facilitate the transfer of substrates 124. The docking station 109 is configured to accept one or more front opening unified pods (FOUPs). Two FOUPS 106A, 106B are shown in the implementation of
Each of the load lock chambers 122 has a first port interfacing with the factory interface 102 and a second port interfacing with the transfer chamber 136. The transfer chamber 136 has a vacuum robot 130 disposed therein. The vacuum robot 130 has one or more blades 134 (two are shown in
The controller 144 is coupled to the processing system 100 and is used to control processes and methods, such as the operations of the methods described herein (for example the operations of the methods as described in other parts of the present disclosure). The controller 144 includes a central processing unit (CPU) 138, a memory 140 containing instructions, and support circuits 142 for the CPU. The controller 144 controls various items directly, or via other computers and/or controllers.
The processing chamber 200 further includes a vacuum pump 214 and a plurality of gas sources 232. A remote plasma source 252 may be coupled with the gas feed of one or more of the gas sources 232 and configured to energize each process gas independently or energize a mixture of two or more of the process gases. The energized process gas is provided to the chamber 200 via a top baffle 236. The vacuum pump 214 is coupled to the processing chamber 200 and configured to adjust the vacuum level within the process region 246 via a valve 216. Vacuum pump 214 is also configured to evacuate spent gases from the processing chamber 200.
The processing chamber 200 also includes a gas plenum 238 contained between the lid 224 and a showerhead 234. The gas sources 232 provide process gases into the gas plenum 238 via a top baffle 236. The gas showerhead 234 includes a plurality of conduits that allow the process gases to flow through.
The processing chamber 200 includes a plurality of plasma sources 226, 228, 230 disposed at various locations of the processing chamber 200 to energize the process gases. As shown in
The pre-pump abatement system 304 may include a plasma abatement unit, such as an Aeris® abatement unit available from Applied Materials, Inc., located in Santa Clara, California, among other suitable systems. The pre-pump abatement system 304 includes a plasma source 314, a reagent delivery unit 312, and a controller 316. The plasma source 314 may be a remote plasma source, an in-line plasma source, or other suitable plasma source for generating a plasma within a treatment region of the pre-pump abatement system 304. According to an embodiment, the plasma source 314 includes a coolant detection leakage system as described in the present disclosure. The reagent delivery unit 312 delivers one or more reagents into the foreline 318 or treatment region according to instructions by the controller 316. The controller 316 is configured to control operations of the pre-pump abatement unit 304. The controller 316 may be similarly configured as the controller 144.
The RF generation system 406 includes an RF power source 408, an impedance matching network 409, a dielectric body 404, and an RF antenna 422 which are connected by a plurality of electrical connections 412. The RF power source 408 is configured to generate RF electric signals. The impedance matching network 409 is configured to match the impedance between the RF power source 408 and the RF antenna 422. The dielectric body 404 includes the dielectric wall 424 and the plasma region 420. According to an embodiment, the dielectric body 404 may be of any shape, such as a tubular shape or any other suitable shapes. The dielectric wall 424 is made of a dielectric material, such as ceramic, quartz or any other suitable materials.
The RF antenna 422 is conductive and is capable of transmitting the RF power signals with little loss. According to an embodiment, the RF antenna 422 is disposed around an external surface 403 of the dielectric body 404, such as the dielectric wall 424, and forms loops around the dielectric wall 424. The RF antenna 422 may be made of a conductive material, such as copper or another other suitable materials.
According to an embodiment, the RF antenna 422 is hollow. As shown in
Electrical connections 412 are also conductive and capable of transmitting the RF power signals with little loss. Electrical connections 412 are made of a conductive material, such as copper, aluminum, or any other suitable materials. But, the electrical connections 412 do not function as liquid channels and do not have an internal channel to flow the coolant 401.
During a plasma generation, the RF power source 408 generates RF electrical signals and transmits the RF electrical signals to the RF antenna 422 via the electric connections 412 and the impedance matching network 409. When process gases 432 flow into the plasma region 420, the process gases 432 are energized by the RF electrical signals transmitted by the RF antenna 422. According to an embodiment, the RF antennas 422 generates an inductively coupled plasma inside the plasma region 420.
As shown in
The coolant channel 410 is configured to flow the coolant 401 through electrical components of the RF generation system 406 to remove heat. An arrow 434 indicates a flow direction of the coolant 401. The coolant channel 410 includes a plurality of channel segments extending through various electrical components of the RF generation system, such as a channel segment 407 in the RF power source 408, a channel segment 436 in the impedance matching network 409, and the RF antenna 422 functioning as its own channel segment. In an embodiment, the plurality of channel segments are serially connected such that the coolant 401 sequentially flows from one electric component to another one of the RF generation system 402. In another embodiment, the channel segments may be connected in parallel.
The first and second flow control devices are configured to control the flow of the coolant 401 into and out of the coolant channel 410. According to an embodiment, the coolant inlet 428 is electrically isolated from the RF generation system 406. The coolant outlet 431 is also electrically isolated from the RF generation system 406. In an embodiment, the channel segments 407 and 436 function as electrical insulators. For example, the channel segments 407 and 436 are made of non-conductive materials, such as rubber, plastic, or any other suitable materials. Although the channel segments 407 and 436 are connected with the RF antenna 422 and the electrical connections 412, electrical signals of the RF generation system 406 may not transmit to the flow control devices because the channel segments 407 and 436 are electrical insulators.
According to an embodiment, the pressure measurement device 418 of the cooling system 402 is configured to detect a pressure of the coolant 401 inside the coolant channel 410. The pressure measurement device 418 may be any device that is capable of measuring a pressure of the coolant 401, such as a pressure gauge or any other suitable devices.
The pressure measurement device 418 may be disposed at any suitable locations along the coolant channel 410. For example, the pressure measurement device 418 may be disposed between the second flow control device 416 and the coolant outlet 431. The pressure measurement device 418 may also be disposed between the first flow control device 414 and the coolant inlet 428. According to an embodiment, the pressure measurement device 418 may be coupled with the controller 316 of the pre-pump abatement unit 304, which is coupled with the controller 144 of the processing system 100. According to another embodiment, the pressure measurement device 418 may be directly coupled with the controller 144 or other system-level controllers. Any one of the controllers 316 and 144 may be configured to determine whether leakage occurs in the coolant channel 410 based on the measured pressure value.
The pressure measurement device 418 is configured to measure pressure levels of the coolant inside the coolant channel 410 during a plasma generation process and/or after a plasma generation process. The pressure measurement device 418 also transmits the measured pressure levels to the controllers 316 and/or 144. The controllers 316 and 144 are configured to receive operational parameters of the pump 426 and the plasma region 420, which are used to determine whether a pressure fluctuation is related to a coolant leak or not. A leak determining method may include examining an immediate change of the pressure level, comparing the measured pressure level with a predetermined threshold or a recorded history of the pressure levels, and any other information.
After a plasma generation process is completed, the first and second flow control devices 414 and 416 are shut off to isolate the coolant 401 inside the coolant channel 410. After the flow control devices are shut off, any pressure fluctuation measured by the pressure measurement device 418 is likely cause by a coolant leak. In an example, when the pressure measurement device 418 detects a pressure drop instantly after the shutoff of the flow control devices, the controllers 316 and 144 can determine that a leak may occur inside the coolant channel 410.
It is contemplated that one or more aspects disclosed herein may be combined. Moreover, it is contemplated that one or more aspects disclosed herein may include some or all of the aforementioned benefits. While the foregoing is directed to embodiments of the present disclosure, other and further embodiments of the disclosure may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.
This application claims benefit from U.S. Provisional Application Ser. No. 63/545,714, filed Oct. 25, 2023, the contents of which is incorporated by reference in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 63545714 | Oct 2023 | US |
