Reactor systems and methods for monitoring lift pin travel in reaction chamber

Abstract

A reactor system with a stuck top pin detection. The system includes a reaction chamber; a base for supporting a wafer within an interior space of the reaction chamber; and a lift for raising and lowering the base within the interior space. Furthermore, the system includes a top pin supported by the base and extending vertically through the base to travel between an upper position and a lower position by moving the base via the lift; and a landing pad disposed in the system for receiving a base of the top pin when it is in the lower position. The system also includes a sensor assembly having a sensor at least partially positioned within the interior space of the reaction chamber. An output signal from the sensor indicates whether the top pin is stuck or engaged during its travel through the base.

Description

[Technical Field]

[0001] This disclosure generally relates to a method and system for lifting a wafer from a pedestal in a wafer processing or reactor system using a top pin, and more specifically, to a method and apparatus for detecting a biting or jamming top pin in a semiconductor processing or reactor system. [Previous Technology]

[0002] Semiconductor processing technologies, including atomic layer deposition (ALD) and chemical vapor deposition (CVD), are commonly used to form thin films of material on substrates, such as silicon wafers. For such processing, reactor systems or tools with reaction chambers are used, with pedestals or substrate holders positioned within the reaction chambers and used to hold the wafer during the wafer processing steps.

[0003] In some reaction system designs, including certain ALD reactor systems or devices, a base is covered, and a top pin extending upward through the base and its cover facilitates wafer unloading by extending a distance above the upper surface of the cover when the base elevator is lowered or in a lower position to lift the wafer away from the base. During this operational phase of the reactor system, the top pin is considered to be in the "upper" position. When the elevator is raised to the upper position to lift or raise the base and its cover, the top pin is configured to travel downward relative to the base such that the top or head of the top pin is flush with or below the upper surface of the cover.

[0004] However, due to several factors, wafer top pins in reactor systems or equipment may become stuck in the upper position. In this undesirable operating condition, the head of the top pin protrudes above the base pouch position when it should be fully retracted below the surface. As a result, the received or dropped wafers may not lie flat on the cover or in the cover (or base) pouch, which can negatively impact wafer handling and lead to the scrapping of produced wafers. For example, a stuck top pin can cause tilted wafers, resulting in uneven deposition due to non-uniform or undesirable wafer temperature distribution, as well as ineffective volumes due to tilted wafers.

[0005] Typically, the problem of stuck or jammed top pins may go undetected until daily monitoring is performed and many wafers are affected. Existing design approaches are not widely effective or adopted. One method of monitoring top pin movement involves using a series of lasers through a lower reaction chamber viewport to try to see if the bottom of the pin is at the appropriate height, indicating that the pin is properly recessed. This is an expensive solution and occupies a viewport that is better suited for visual inspection and maintenance. Furthermore, the viewport or window can fog up due to leaking precursors, such as from the upper reaction chamber to the lower wafer transfer chamber, which will obstruct proper inspection. Another proposed design involves allowing current to pass through or not through the contact pin bottom and pin pad; however, in the reaction chamber, a film of dielectric or similar material may form on the pad or pin, which will change the resistance over time and reduce the accuracy of pin monitoring methods.

[0006] Therefore, there is a need for a method to accurately and cost-effectively detect the occurrence of stuck top pins, so as to alert the user of the reactor system or one of its chambers to stop production until the problem can be identified and resolved. [Summary of the Invention]

[0007] This invention is provided to introduce a series of concepts in a simplified form. These concepts will be described in further detail below in the embodiments of the examples disclosed herein. This invention is not intended to identify key or essential features of the claimed subject matter, nor is it intended to limit the scope of the claimed subject matter.

[0008] More specifically, this specification provides a reactor system with a stuck top pin detection. The system includes a reaction chamber; a base for supporting a wafer within an internal space of the reaction chamber; and a lift for raising and lowering the base within the internal space. Furthermore, the system includes a top pin supported by the base and extending vertically through the base to travel between an upper position and a lower position by moving the base via the lift; and a landing pad disposed in the system for receiving a base of the top pin when it is in the lower position. Obviously, the system also includes a sensor assembly having a sensor at least partially positioned within the internal space of the reaction chamber. An output signal from the sensor indicates whether the top pin is stuck or engaged during its travel through the base.

[0009] In some useful embodiments, the sensor assembly further includes a detection module that displays data based on the sensor's output signal, or processes the sensor's output signal to detect when the top pin jams or engages during its travel through the base. In these embodiments, the output signal provides a sensed temperature or pressure, and the detection module's processing of the output signal includes comparing the sensed temperature or pressure with a predetermined temperature or pressure disturbance related to the travel of a top pin that is not jammed or engaged, or includes comparing the timing of the sensed temperature or pressure with the movement of the elevator.

[0010] In these or other embodiments, the system may also include a cover covering an upper surface of the base, and the sensor may include a temperature sensor located within a channel disposed in a body of the cover, thereby outputting a signal correlated with a sensed temperature of the cover. In this case, the temperature sensor may include a thermocouple or a resistance temperature detector positioned near a central axis of the cover. Additionally, the temperature sensor may include a conduit extending away from the thermocouple or resistance temperature detector for carrying the output signal, and the conduit may include two or more coils within the interior space of the reaction chamber. In the same or other cases, the temperature sensor may include a thermocouple or a resistance temperature detector positioned at a radial distance from an edge of the cover, the radial distance being in the range of 40 mm to 60 mm.

[0011] In other embodiments of the system, the sensor may include a temperature sensor located within the landing pad, thereby outputting a signal correlated with a sensed temperature of the landing pad. In this embodiment, the temperature sensor may include a thermocouple or a resistance temperature detector located in a head of the landing pad, the head of the landing pad being adapted to receive the base of the top pin.

[0012] In other exemplary embodiments, the sensor includes a gas inlet in the landing pad, a pressure sensor disposed outside the reaction chamber, and a flow line that fluidly couples the landing pad to the pressure sensor, thereby outputting a signal correlated with a sensed pressure in the flow line. In this embodiment, the gas inlet may include an orifice in a head of the landing pad. Then, when the top pin is in the lower position, the base of the top pin blocks or obstructs gas flow through the orifice, and the sensor assembly may further include a gas pump coupled to the flow line, the gas pump being operable to extract gas from the interior space of the reaction chamber through the landing pad and the flow line.

[0013] According to some aspects of the specification, a method for monitoring the movement of a top pin in a reaction chamber is provided. The method includes using a temperature sensor to sense the temperature of a base cover under an operating state of the reaction chamber. The method also includes comparing the temperature of the base cover with a predetermined range of expected temperatures for the operating state of the reaction chamber. The method further involves generating a warning message or updating a graphical user interface (GUI) indicating a stuck top pin when the comparison result determines that the temperature of the base cover exceeds the predetermined range of expected temperatures.

[0014] In some embodiments of this method, the operating state of the reaction chamber is related to dropping a wafer onto one of the upper surfaces of the base cover. In these or other embodiments of the method, the temperature sensor includes a thermocouple or a resistance temperature detector located within the base cover.

[0015] All of these embodiments are intended to fall within the scope of this disclosure. Those skilled in the art will readily understand these and other embodiments from the following detailed description of some embodiments with reference to the accompanying drawings. This disclosure is not limited to any of the specific embodiments(s) discussed.

Implementation Method

[0017] While certain embodiments and examples are disclosed below, those skilled in the art will understand that this disclosure extends beyond the specific embodiments and / or uses disclosed herein, as well as their obvious modifications and equivalents. Therefore, it is intended that the scope of this disclosure should not be limited to the specific embodiments described herein.

[0018] The illustrations presented herein are not intended to be actual views of any particular material, device, structure, or apparatus, but are merely representations used to describe embodiments of the present disclosure.

[0019] As described below in more detail, the various details and embodiments of this disclosure can be used in conjunction with reactor systems having one or more reaction chambers configured for a variety of deposition processes, including but not limited to ALD, CVD, metal-organic chemical vapor deposition (MOCVD), molecular beam epitaxy (MBE), physical vapor deposition (PVD), plasma-enhanced chemical vapor deposition (PECVD), and plasma etching. Embodiments of this disclosure can also be used in semiconductor processing systems configured to process substrates with reactive precursors, which may also include etching processes such as, for example, reactive ion etching (RIE), capacitively coupled plasma etching (CCP), and electron cyclotron resonance etching (ECR).

[0020] The inventors recognized the importance of sensing or detecting when a top pin engages or jams to prevent or delay its movement from an upper position to a lower position. To address this problem, a reactor system is described herein configured to provide a relatively simple and cost-effective method for detecting the occurrence of one or more jamming pins and, in response, alerting the reactor system operator to address the aforementioned problem. In short, the reactor system design includes a sensor assembly adapted to sense or detect when a top pin engages or jams, causing it to be temporarily or permanently held in an upper position (its top or head above the surface of the base or base cover). The detection module or routines running by the processor of the sensor assembly process sensor signals (or sensor data) to determine when a pin is stuck or engaged (e.g., by identifying temperature or pressure disturbances from normal operating parameters, by identifying when the top pin is not mated to the pin pad, etc.), and in some cases, the response is to generate a stuck pin warning, which is transmitted (e.g., via a graphical user interface (GUI), via text message, or etc.) to the operator of the reactor system to take action.

[0021] The sensor assembly can use a variety of sensors to sense stuck top pins in the reactor system. In one embodiment, the sensor is disposed on a pin landing pad to sense a stuck top pin, for example, by detecting the absence of a pin during operation when the pin should be received on the pad. In this case, the sensor may be in the form of a capacitive sensor disposed on each pin landing pad (e.g., suitable for a particular chamber environment under vacuum, such as 300°C or the like, and having a small size for mounting on the pin landing pad). In other embodiments (shown in detail in the figures), the sensor assembly is configured for thermal monitoring or pressure monitoring to detect stuck top pins.

[0022] The advantage of each of these technologies lies in their durability and low cost relative to the chamber environment. For thermal sensing, thermocouples are known to be useful in the low-pressure and thermal environments associated with semiconductor processing. For pressure sensing, a small leak can be used to allow pressure detection outside the chamber in an ambient, non-harsh environment with relatively inexpensive, durable, and small-footprint components that do not affect the service of the reactor system.

[0023] Thermal monitoring may include monitoring the temperature of the landing pin or base cover. In a landing pin embodiment, thermal monitoring is performed on each of the pin landing pads, wherein a detection module or algorithm operates to find temperature changes (i.e., expected temperature changes) associated with the hot pin contacting the cooler landing pad. In this implementation, a temperature sensor (e.g., a thermocouple or a resistance temperature detector (RTD)) is placed from the rear onto the underside of the pin pad surface (e.g., where the pin remains when the lift is in a lower or reduced position to expose the pin for wafer transfer).

[0024] The concept used in the thermal monitoring embodiment is that when the pin is on the pad, the temperature sensor will be at one temperature, and when the pin leaves the pad, the temperature sensor and the pad will be at a different or second temperature. The detection module / software can use an algorithm that searches for absolute temperature or rapid temperature changes during lift movement to compare the current reactor system behavior with a set of predefined or known "good" or expected behaviors when the top pin is not stuck. If no temperature change occurs at all, or occurs at a different time relative to other top pins, an alert or warning can be issued to stop manufacturing and initiate visual troubleshooting. Deposits on the pin or pad should not substantially alter the behavior from this known temperature baseline. A similar monitoring algorithm can be used when the temperature sensor is placed in the base or its cover.

[0025] Pressure or vacuum sensing embodiments include a sensor assembly configured to monitor pressure or pressure changes to determine when or whether a top pin descends to contact the corresponding landing pad, which alters gas conduction through the orifice in the pad by increasing resistance or blocking the orifice. In some embodiments, a hole is drilled through the pin-pad assembly to allow a small amount of gas flow from the lower chamber (e.g., an inert gas such as nitrogen) to the front of the process or other dedicated venting device when the pin is in the upper position. When the pin and its base contact the pad, the orifice is blocked or at least partially blocked, and the pressure below the drain hole in the pad drops and approaches the pressure of the venting device. A pressure sensor can be used to identify when or whether this occurs. Alternatively, a pressure switch can be used to detect flow or low flow conditions in the pad assembly and trigger a digital output / signal for each pin. The detection module can then be used to trigger a warning or alert during lift movement or operation, based on, for example, a comparison of the pins with each other or a comparison of the pins with a known or predetermined acceptable or expected ("good") pressure baseline.

[0026] Figure 1 is a simplified cross-sectional view of a portion of a reaction chamber 100, which may be disposed in a reactor system. The chamber 100 has a sidewall 104 in which a viewing port 106 is provided for visual inspection of the internal space of the chamber 100. The chamber 100 has a conventional layout having a lift 120 movable upward and downward between an upper and lower position (or a wafer loading and unloading position), as indicated by arrow 121. The lift 120 supports and moves a base 130, which has a cover 132 adapted with an upper surface 133 for supporting a wafer (not shown) during a deposition process in the chamber 100, wherein the lift 120 and the base 130 are shown in the lower position in Figure 1.

[0027] To facilitate wafer loading and unloading, a landing pad assembly 140 is shown, which includes a fixed landing pad 142. Additionally, a plurality of top pins are provided, each top pin being paired with a landing pad assembly 140 (e.g., three top pin pairs each paired with one landing pad assembly 140). As shown, a top pin 150 is configured to mate with the landing pad assembly 140. The top pin 150 includes an elongated body or shaft 152 extending through a channel in the base 130 and the cover 132, and a head 154 is disposed at the top or tip of the body 152. When the base 130 is in a lower position due to the movement 121 of the lifter, the head 154 extends above the upper surface 133 of the cover 132.

[0028] For this purpose, the top pin 150 includes a base 156 at the bottom end or base of the body 152, which engages with the landing pad 142 to stop or limit the downward movement of the pin 150 using the lift 120. A spring 158 extends above the outer surface of the body 152 and contacts the lower portion of the base 130 (or another component attached to the base 130), and is compressed when the lift 120 moves 121 to the lower position, and is released when the lift 120 moves 121 to the upper or raised position to move to its resting configuration. When deposition or other processes may occur in the chamber 100, this causes the pin 150 to descend to be flush with or below the surface 133 of the cover 132. However, when the pin 150 is stuck or engaged, the spring force may be insufficient to properly move the pin 150 downward, or this movement may be delayed.

[0029] Figure 2 is an enlarged view of a portion of the reaction chamber 100 of Figure 1, showing in more detail the top pin 150 and landing pad assembly 140. As shown, the pin guide / sleeve 260 is configured to engage with the lower surface of the base 130, serving to guide the vertical movement of the body 152 of the top pin 150. The pin guide / sleeve 260 also acts as a mating surface for the upper end of the spring 158 to limit its upward movement and is aided by the downward movement of the lift and base 130. In Figure 2, the base 130 is in the upper or raised position, and the spring 158 has been released to its rest (or near-so) position to move the pin body 152 downward relative to the base 130 and the cover 132, such that the head 154 of the top pin 150 is recessed or flush with the upper surface 133 of the cover 132, as required for wafer placement / support on the cover 132 during processing. A gap 270 with a high hgap (e.g., 15 mm to 35 mm or greater) is formed between the landing pad 142 and the base 156 of the top pin 150.

[0030] As can be seen from Figures 1 and 2, the conventional chamber and top pin design allows the base 130 to move downwards for wafer loading, which pushes the pin 150 upwards when the bottom or base 156 of the pin 150 contacts the landing pad 142 (which can be mounted to the base plate of the chamber 100). The base 130 moves upwards by the movement 121 of the elevator 120 within the chamber 100 to handle the wafer received on the surface 133 of the cover 132. The top pin 150 travels upwards with the base 130 and is no longer in contact with the landing pad 142. A spring 158 forces the pin head 154 to retract into the base 130 or its cover 132. When the wafer is in place, it may be difficult to track the position of the pin head 154 within the chamber 100 from an available side viewport (such as a viewport 106 in the side wall 104 of the chamber 100).

[0031] Now, turning first to a thermal monitoring method for detecting stuck pins, Figure 3 illustrates a schematic diagram of a portion of a reactor system 300 configured according to this specification to detect stuck or engaged pins using temperature sensors positioned in the landing pads. The inventors recognized that the pins will have a higher temperature when in the processing position (where the elevator and base are in an elevated or up position) compared to the landing pads, which will be at a lower steady-state temperature. With this in mind, a temperature sensor can be installed in-situ on each pin landing pad to monitor temperature changes as the pin rests against the pin to detect when the pin is stuck, for example, when the temperature of one pad does not increase as expected or in a similar manner to the other pads.

[0032] As shown in Figure 3, the reactor system 300 includes a reaction or vacuum chamber 310 having an internal space 315 for processing wafers. The chamber 310 can typically be configured similarly to the chamber 100 of Figure 1, having landing or pin pads 318 (as shown in Figure 4 and understandable from Figures 1 and 2) arranged to engage with a similar number of top pins supported on a base. A sensor assembly 320 is included in the reactor system 300 and is adapted to detect when one of the top pins becomes stuck via thermal monitoring in the internal space 315 of the chamber 310.

[0033] The sensor assembly 320 includes temperature sensors 322, 324, and 326 (shown as thermocouples, but may take other forms, such as RTDs or similar) in space 315. More specifically, thermocouples 322, 324, and 326 are mounted in each of a pin or landing pad 318 in space 315 (three are shown in this non-limiting example). A communication line 329 extends outward from each thermocouple 322, 324, and 326 out of chamber 310 via a TC feed channel 328.

[0034] The sensor assembly 320 includes a processor 330 that executes software, code, or instructions (possibly in memory 340) to provide the functionality of the detection module 332 (including processing signals from thermocouples 322, 324, and 326). Furthermore, the sensor assembly 320 includes memory or data storage 340 managed by the processor 330 to facilitate the operation of the detection module 332. For this purpose, memory 340 may store a set of predetermined baseline parameters or setpoints 344 for use in the operation of the system 300. These may include the expected temperature and / or temperature increase of the pad 318 when the top pin rests against or contacts the pad 318. Parameters 344 may also include the timing of the elevator movement to allow the detection module 332 to match the elevator movement (and corresponding base position) with the measured temperature of the pad 318.

[0035] For example, module 332 may determine that an expected temperature disturbance (rise in pad temperature) for one or more pads 318 is not seen or is delayed, and in response, may generate an alert or warning that a pin may be stuck. This alert may be transmitted to the user or operator of system 300, such as via a graphical user interface (GUI) 350 on a monitor / display device. In some cases, the outputs of thermocouples 322, 324, and 326 (sensed pad temperatures) are displayed on the GUI 350 to provide real-time (or near-real-time) monitoring of the pad temperature and / or temperature changes between pads 318 (e.g., when a pin is expected to move against pad 318 via a lift). For example, tests may indicate that there may be a delay of 3 to 4 seconds in the case of a pin getting stuck, and this delay of the temperature disturbance may be used by the detection module as an indicator of a stuck pin (e.g., a delay greater than "X" generates an alert, or a delay in the range of "Y to Z" generates such an alert).

[0036] Figure 4 illustrates a simplified cross-sectional view of a portion of the reaction chamber 400, in which thermal monitoring provided by system 300 can be implemented. As shown, the chamber 400 includes an internal space 405 in which a lift 420 is provided to support and selectively raise and lower a base 430. A plurality of (e.g., three) top pins are supported by the base 430 and move with it during operation of the lift 420. The base 430 is shown in an upper or raised position. In this operating state of the chamber 400, the top pins 450 are also raised such that their bottom or base 456 is spaced apart from the corresponding pin or landing pad 442.

[0037] The landing pad 442 (and other pads in the chamber 400) is modified to include temperature sensors (not visible in FIG. 4, but shown in FIG. 3, 5 and 6), such as thermocouples or RTDs, and communication or connection wires / lines 443 are shown as communicatively connecting the temperature sensors in the landing pad 442 to other components of the sensor assembly (e.g., assembly 320 in FIG. 3) (e.g., processor 330 and / or TC feed channel) to provide their output data / signals (e.g., sensed temperature of pad 442) for display and / or further processing.

[0038] Figure 5 is an enlarged view of the reaction chamber of Figure 4, showing in cross-section more details of the design supporting thermal monitoring to detect the pin or landing pad that is holding the top pin in place. View 550 is further enlarged to show the modifications to the landing pad 442 in more detail. As shown, the top pin 450 is in the lower or pin-stop position (e.g., in response to the lowering of the elevator base), wherein its base 456 rests against or abuts against the upper surface of the pin or landing pad 442. In this position, heat from the pin 450 is transferred to the pad 442 via conduction, causing its temperature to rise.

[0039] Compared to conventional pads, the pin pad 442 is modified to have an increased thickness (or head thickness) tpad to allow the thermocouple 545 to be mounted within the pad 442. For example, the thickness may be increased by 2 to equal or greater than 4 mm to allow the thermocouple 545 to be received in a recess or channel within the pad 442. This allows the thermocouple 545 to contact the material of the pad 442 and be close to the upper surface of the base 456 of its abutment / receive pin 450 (e.g., actual proximity is such as within 0.5 mm to 2 mm or similar) to facilitate temperature monitoring. Generally, as shown, the thermocouple 545 is positioned at or near the center of the pad 442 to obtain more accurate readings.

[0040] In some applications of the thermal monitoring concept, it may be necessary to monitor other components in the reaction chamber to detect a stuck or jammed pin. In one useful instance, the inventors determined that it may be necessary to monitor the temperature of the base cover, rather than the temperature of the pin or landing pad, to detect the presence of a stuck or jammed top pin based on temperature changes.

[0041] During wafer processing, when the cold wafer is dropped or placed on the upper surface of the pedestal (i.e., when the pedestal is raised by the elevator so that the head of the top pin, under spring force, becomes concave or flush with the cover surface when operating normally or not jammed), the pedestal cover will experience expected temperature disturbances or changes. When no temperature drop is observed or the temperature drop is not delayed, this baseline range or parameter (e.g., a temperature drop of 2 °C to 8 °C or similar, where in some chamber designs some tests show 2.5 °C to 3 °C, while others show a drop of 5 °C to 6 °C) can be used to detect jamming pins. Temperature sensors such as thermocouples can be provided in the pedestal cover to monitor its temperature.

[0042] This alternative embodiment will be implemented by modifying the system 300 of FIG3, wherein (typically) a single thermocouple installed within the base cover rather than within the landing pad (or the head of such a pad) replaces the three thermocouples 322, 324, 326. The baseline parameter 344 may be modified to provide the expected temperature changes of the base cover and / or the timing of such changes in relation to the movement of the elevator, and the detection module 322 will process the sensed temperature of the base cover to identify possible jamming or pin-locking conditions (e.g., a small temperature drop (e.g., a difference in sensed temperature drop of 2 °C to 3 °C) or delayed temperature disturbances), wherein alerts / warnings or monitoring data are transmitted to the user, such as via the GUI 350.

[0043] FIG6 is a side cross-sectional view of a portion of a reaction chamber 600 according to another embodiment of this specification, having a base cover 632 adapted for thermal monitoring. FIG7 is an enlarged view of a portion of the base cover 630 of FIG6 before the insertion of a thermocouple 670 (or other temperature sensor), illustrating additional features of the modified cover. As shown, the chamber 600 includes an internal space 605 in which a lift 620 is provided, which supports and raises and lowers the base 630. The cover 632 is located above the base 630 to move with it and has an upper surface 633 facing upward in the space 605. During wafer processing operations, before deposition and other processes, a cold wafer is dropped onto the surface, and the base cover 632 is configured to provide thermal monitoring for detecting stuck top pins (not shown, but can be understood from FIG1 to FIG5).

[0044] In this case, the sensor assembly will include a temperature sensor 670, which may be in the form of a thermocouple (e.g., a TC with a stainless steel (SS) sheath). Its head or sensor element 674 is located at the end of a channel 638 (e.g., a drilled hole) in the body of the base cover 632, such that it is located at or near the axial center of the cover 632. As shown in FIG7, the channel 638 extends from the inlet 782 to an internally positioned end wall 784, against which the sensor element (or TC) 674 is positioned on the assembly. The sensor element or end (or TC or RTD) may be positioned at a sensing location substantially close to the surface 633 of the cover 632 (e.g., 0.5 mm to 2 mm from the surface 633 of the cover) to provide more accurate temperature sensing.

[0045] To facilitate the maintenance and installation of the temperature sensor 670, several slots / windows 788 (e.g., machined slots or similar) are provided on the bottom surface of the base cover 632 to provide access to the channel 638, allowing an assembler to push or guide the temperature sensor 670 along the channel 638. Screw holes 789 are provided in the lower surface of the cover 632 to allow the insertion of fixing screws to secure the sensor 670 in the channel 638. Since the lift 620 will repeatedly rise and fall (e.g., in some cases, a vertical travel of 40 mm is expected), conventional thermocouples may be damaged due to stretching and fatigue. Therefore, the sensor line 678 is shown in a pigtail configuration with two, three, or more coils to provide a spring-like effect, which provides relief and adjustment for movement of the cover 632 on the lift 620 and base 630, and prevents wear or damage to the sensor 670.

[0046] In some embodiments, a less centered sensing position may be selected to reduce the overall length of the portion of the sensor (or wire) within the body of the cover (e.g., from about 6 inches to about 3 inches or less). For example, FIG8 is a side cross-sectional view of the reaction chamber 600 of FIG6, illustrating an additional base cover configuration for facilitating thermal monitoring for detecting a stuck top pin, and FIG9 is an enlarged view of a portion of the base cover 832 of FIG8 before the insertion of the thermocouple 674, illustrating additional features of the modified cover 832.

[0047] As shown, the design is similar to that of Figure 6, with several differences. The channel 838 in the body of the cover 832 for receiving and positioning the thermocouple 674 is much shorter, and its radial distance (or distance from the outer edge of the cover 832) d can be in the range of 40 mm to 60 mm, rather than the entire radius of the cover 832 as shown in Figure 6 (or a smaller amount, such as 10 mm to 20 mm less than the radius of the cover). The thermocouple 674 will again be located near the surface 833 of the cover 832 within the channel 838, and it is believed that the temperature measurement will be equivalent to that achieved by the embodiments of Figures 6 and 7.

[0048] As seen in Figure 9, the shortened hole / channel 838 exits via an outlet 882 on the side of the cover 832 rather than via the bottom surface of the cover 832. The notch or window shown in Figure 7 is also eliminated because the sensor wire is less likely to become bent or deformed in the shorter operating channel 838. As shown in Figure 8, the channel 838 terminates at an inner end wall 884, where the thermocouple / sensor element 674 will be positioned abutting against the inner end wall 884 in its final sensing position during assembly. A screw hole 889 in the bottom surface of the body of the cover 832 is provided near this end wall 884 to allow the insertion of a fixing screw (not shown) to secure the sensor 670 within the cover 832. The hole / channel 838 may have two diameters for receiving the sensor element / TC 674 with a smaller outer diameter near the end wall 884 and the sheathed wire with a larger outer diameter near the channel inlet 882.

[0049] Now, turning to the use of pressure monitoring to detect stuck top pins, Figure 10 illustrates a schematic diagram of a portion of reactor system 1000 configured according to this specification to utilize a pressure sensor having an inlet set or positioned in a landing pad within the reaction chamber to detect stuck or jammed top pins. The inventors recognized that by providing a gas flow through the pin or landing pad within the reaction chamber, pressure changes can be monitored to detect stuck top pins. Specifically, a continuous vacuum pump can be provided from the base of the pin pad through a central orifice. Then, as the pin rises, absolute pressure is sensed, and when the base of the pin contacts the pin pad and covers or blocks the orifice or pressure sensor inlet, exhaust pressure is sensed. When the pin rests against the pin pad, pressure drop can be monitored by individual sensors for each pin (e.g., pressure sensors, pressure gauges, etc.), and based on this monitored pressure, an alert or warning can be generated and transmitted to the operator of system 1000.

[0050] As shown in FIG10, the reactor system 1000 includes a reaction or vacuum chamber 1010 having an internal space 1015 for processing wafers. The chamber 1010 may generally be configured similarly to the chamber 100 of FIG1, having landing or pin pads 1022 (as shown in FIG4 and understood from FIG1 and FIG2) arranged to engage with a similar number of top pins 1018 supported on a base. A sensor assembly 1020 is included in the reactor system 1000 and is adapted to detect when one of the top pins 1018 is stuck by pressure monitoring of airflow through an inlet in each of the pads 1022 disposed within the internal space 1015 of the chamber 1010.

[0051] The sensor assembly 1020 includes a pressure sensor 1028 fluidly connected via separate gas flow lines 1026. Each gas flow line 1026 is coupled to one of the inlets / holes 1024 in one of the pads 1022 and extends from the interior space 1015 of the chamber 1010 to an external space or location outside the chamber 1010. For example, each pressure sensor 1028 may take the form of a pressure sensor, a pressure switch, or other pressure sensing device fluidly connected to the line 1026, and may provide a vacuum pump 1029 to provide continuous vacuum pumping from the base of each pin pad 1022. In this way, the pressure sensor 1028 will generate a signal or output indicating an absolute or near-absolute pressure when the pin 1018 is raised, and an exhaust pressure or near-exhaust pressure when the base of the pin 1018 is on or in contact with the pin pad 1022.

[0052] The sensor assembly 1020 includes a processor 1030 that executes software, code, or instructions (possibly in memory 1034) to provide functionality for the detection module 1032, including processing signals from the pressure sensor 1028 to detect a stuck or engaged pin. Furthermore, the sensor assembly 1020 includes memory or data storage 1034 managed by the processor 1030 to facilitate the operation of the detection module 1032. For this purpose, memory 1034 may store a set of predetermined baseline parameters or setpoints 1036 for use in the operation of the system 1000. These may include the expected timing and (in some cases) magnitude of pressure drops in the conduits 1026 (each associated with a pad 1022 and a top pin 1018).

[0053] For example, a test can be performed to determine the pressure drop experienced when the elevator in chamber 1010 moves to position the pin 1018 against the pad 1022, and these values ​​can be stored as a parameter / setpoint 1036 to identify when a stuck pin 1018 (e.g., when no pressure drop is observed for an expected or delayed time) abuts or contacts the pad 1022 (and covers or blocks the inlet 1024 to the line 1026 (which may take the form of a drain hole in the pad 1022)). Parameter 344 may also include the timing of the elevator movement to allow the detection module 332 to match the elevator movement (and corresponding base position) with the measured temperature of the pad 318.

[0054] Module 1032 may cause the pressure sensed by sensor 1028 to be displayed on a GUI 1040 on a monitoring device such as a user's. In other cases, module 1032 may process the signal from sensor 1028 and baseline parameters / setpoint 1036 to determine if a anticipated pressure change (an increase or decrease in pressure in line 1026) is not seen or delayed for one (or more) of pads 1022, and in response, may generate an alert or warning that may be causing pin 1018 to jam. This alert may be transmitted to the operator or user of system 1000, such as via GUI 1040 on a monitor / display device. In some cases, the outputs (sensing pressure) of thermocouples 322, 324 and 326 are also displayed on GUI 1040 to provide real-time (or near-real-time) monitoring of pressure changes between pad 1022 (or line 1026) (e.g., sensing pressure when pin 1018 is expected to rest against pad 1022 as it moves via the lift).

[0055] FIG11 is a side cross-sectional view of a pin-pad assembly 1140 configured according to this specification, such as a pad 1022 in the sensor assembly 1020 of FIG10, and a top pin 150 in a lower position. For pressure monitoring, the top pin 150 does not need to be modified, and its components may be those described in FIG2, including a body 152 and a base 156 (having a lower flat surface) at the lower end or lower part of the body 152.

[0056] To monitor pressure, a new pin or landing pad assembly 1140 is provided for each top pin 150. As shown, the assembly 1140 includes a pin pad 1142 having an elongated body 1144 and a head 1143 extending from the upper end of the body 1144 to receive the base 156 of the pin 150 during operation of the reactor system. The pin pad 1142 is configured to provide a gas flow path from the reaction chamber (e.g., the internal space 1015 of chamber 1010 in FIG. 10) to a gas flow line 1160 that extends out of the chamber. For this purpose, the head 1143 includes a drain hole or through-hole 1145, which serves as an inlet for gas flow to the pressure sensor and extends from the upper surface of the head 1143 through the body 1144.

[0057] The landing pad 1142 is supported on the base 1146 (which in turn is supported on the lower assembly of the reaction chamber). The base 1146 includes a channel 1147 defining a gas flow path through the base 1146, and when the landing pad 1142 is connected to the base 1146, an inlet or through-hole 1145 is fluidly coupled to the channel 1147, allowing gas to flow through the assembly 1140. As shown, a coupling or sealing member 1150 (e.g., a C-seal or the like) is provided to couple a gas flow line 1160 to the base 1146, such that the channel 1147 is coupled to the pipe / line 1160 (or its inlet).

[0058] As illustrated in Figure 10, the pump can be coupled to line 1160 to draw gas from the space surrounding assembly 1140 through inlet 1145 and passage 1147, and the pressure in line 1160 can be monitored to determine if pin 150 is stuck (improperly moving up and down through the base). When pin 150 is in the lower position (as shown in Figure 11) and pin base 156 abuts against the land or head 1143 of pin pad 1142 (e.g., pin 150 covers or blocks drain hole or through hole / inlet 1145), gas flow is blocked or at least obstructed. When pin 150 is later raised (by operation of a lift mechanism that moves the base), flow through inlet 1145 is restored.

[0059] Figure 12 is a top perspective view of a portion of the reactor system 1200, showing the internal space 1215 of the reaction chamber 1210, which includes three pin assemblies of Figure 11, each pin assembly paired with a top pin. As a specific example, pin assembly 1140 is shown to be paired with and receive top pin 150 (shown in the lower position). Pin assembly 1140 is mounted to the lower wall 1212 of chamber 1210 and configured to receive top pin 150 during its vertical travel (e.g., during elevator movement through and using the base (not shown in Figure 12, but can be understood from Figures 1 and 4)).

[0060] The internal space 1215 of chamber 1210 is further defined by sidewall 1214, and each pad assembly 1140 is provided with individual and separate gas lines to sense the pressure of the gas flowing through each assembly 1140 during operation of system 1200. As shown, gas flow line 1160 is coupled to landing pad assembly 1140 and extends along the upper surface of bottom wall 1212 to sidewall 1214. It then passes through sidewall 1214 and is coupled to outer section 1261. Pressure sensor 1266 is in fluid communication with outer section 1261 of flow line 1160 and operates to sense pressure in the line, which will change according to the position of top pin 150 relative to the pad of assembly 1140 (e.g., pad 1142 in FIG. 11). In this way, the pressure at each pad assembly 1140 (of which three are shown to correspond to the three top pins) can be sensed and compared with each other or with a expected baseline to determine whether one or more of the top pins 150 may be stuck or locked (e.g., a change in the timing or amount of pressure change determined by the detection module to indicate a stuck pin 150).

[0061] Benefits, other advantages, and solutions to problems have been described herein with reference to specific embodiments. However, benefits, advantages, solutions to problems, and any elements that may cause any benefit, advantage, or solution to occur or become more apparent should not be construed as essential, necessary, or fundamental features or elements of this disclosure.

[0062] References to features, advantages, or similar language throughout this specification do not imply that all features and advantages achievable with this disclosure are, or are contained herein, any single embodiment of the invention. Rather, references to features and advantages should be understood as meaning that a particular feature, advantage, or characteristic described with respect to the same embodiment is included in at least one embodiment of the subject matter disclosed herein. Therefore, the discussion of features and advantages and similar language throughout this specification may, but are not necessarily, refer to the same embodiments.

[0063] Furthermore, the features, advantages, and characteristics described in this disclosure may be combined in any suitable manner in one or more embodiments. Those skilled in the art will recognize that the subject matter of this application may be practiced without having one or more of the specific features or advantages of a particular embodiment. In other instances, additional features and advantages may be recognized in certain embodiments, which may not be present in all embodiments of this disclosure. Furthermore, in some instances, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring the nature of the subject matter of this disclosure.

[0064] The scope of this disclosure is therefore limited only by the appended claims, wherein, unless expressly stated otherwise, reference to an element in the singular form is not intended to mean "one and only one," but rather "one or more." It should be understood that, unless otherwise specifically stated, "a / an" and / or "the" can include one or more, and reference to an item in the singular form can also include items in the plural form. Furthermore, the term "plurality" can be defined as "at least two." As used herein, when used with a list of items, the phrase "at least one" means that different combinations of one or more of the listed items may be used, and possibly only one of the listed items may be required. An item may be a particular object, thing, or category. Furthermore, when phrases like "at least one of A, B, and C" are used in the claims, it is intended that the phrase be interpreted as meaning that A can exist alone in one embodiment, B can exist alone in one embodiment, C can exist alone in one embodiment, or any combination of elements A, B, and C can exist in a single embodiment; for example, A and B, A and C, B and C, or A, B, and C. In some cases, "at least one of item A, item B, and item C" can mean, for example, but not limited to, two items A, one item B, and ten items C; four items B and seven items C; or some other suitable combination.

[0065] All scope and ratio limitations disclosed herein may be combined. Unless otherwise specified, the terms "first," "second," etc., are used herein only as labels and are not intended to impose any order, position, or hierarchy requirements on the items referred to by such terms. Furthermore, references to items such as "second" do not require or exclude the existence of items such as "first" or lower numbered items, and / or items such as "third" or higher numbered items.

[0066] Any reference to attachment, fixation, connection, or the like may include permanent, removable, temporary, partial, complete, and / or any other feasible attachment option. Additionally, any reference to no contact (or similar phrase) may also include reduced contact or minimal contact. In the foregoing description, certain terms may be used, such as “up,” “down,” “upper,” “lower,” “horizontal,” “vertical,” “left,” “right,” and the like. Where applicable, these terms are used to provide some clarification in dealing with relative relationships. However, these terms are not intended to imply absolute relationships, positions, and / or orientations. For example, with respect to an object, simply turning the object over can transform the “upper” surface into the “lower” surface. Nevertheless, it remains the same object.

[0067] Additionally, in this specification, examples of one element being "coupled" to another element can include direct and indirect coupling. Direct coupling can be defined as one element being coupled to another element and having some contact with it. Indirect coupling can be defined as coupling between two elements, wherein the coupled elements do not directly contact each other, but have one or more additional elements between them. Furthermore, as used herein, securing one element to another element can include both direct and indirect securing. Additionally, as used herein, "adjacent" does not necessarily mean contact. For example, one element may be adjacent to another element without contacting that element.

[0068] Although exemplary embodiments of the present disclosure are presented herein, it should be understood that the disclosure is not limited thereto. For example, although reactor systems are described together with various specific configurations, the disclosure is not necessarily limited to these examples. Various modifications, changes, and enhancements may be made to the systems and methods presented herein without departing from the spirit and scope of the disclosure.

[0069] The subject matter of this disclosure includes all novel and non-obvious combinations and sub-combinations of the various systems, components and configurations and other features, functions, actions and / or properties disclosed herein, as well as any and all equivalents thereof. [Simplified Explanation of the Diagram]

[0016] Although this specification concludes with the claims specifically pointed out and explicitly asserted as being entitled to the embodiments of this disclosure, the advantages of the embodiments of this disclosure can be more readily appreciated from the description of certain examples of the embodiments when read in conjunction with the accompanying drawings. Element numbersed similarly throughout the drawings are intended to be identical. Figure 1 is a simplified cross-sectional view of a portion of a reaction chamber having a known layout, having a base with a cover adapted to support the wafer during the deposition process, and showing a known top pin and landing pad assembly. Figure 2 is an enlarged view of a portion of the reaction chamber of Figure 1, showing the top pin and landing pad assembly in more detail. Figure 3 illustrates a schematic diagram of a portion of a reactor system configured according to this specification to detect a stuck top pin using a temperature sensor positioned in the landing pad. Figure 4 is a simplified cross-sectional view of a portion of a reaction chamber similar to Figure 1, adapted to provide thermal monitoring using a pin in the chamber or a temperature sensor in the landing pad. Figure 5 is an enlarged view of the reaction chamber of Figure 4, showing in cross-section more details of the pin or landing pad design supporting thermal monitoring. Figure 6 is a side cross-sectional view of a portion of the reaction chamber according to another embodiment of this specification, having a base cover adjusted for thermal monitoring. Figure 7 is an enlarged view of a portion of the base cover of Figure 6 before thermocouple insertion, illustrating additional features of the modified cover. Figure 8 is a side cross-sectional view of the reaction chamber of Figure 6, illustrating an additional base cover configuration for facilitating thermal monitoring for detecting a stuck top pin. Figure 9 is an enlarged view of a portion of the base cover of Figure 8 before thermocouple insertion, illustrating additional features of the modified cover. Figure 10 illustrates a schematic diagram of a portion of a reactor system configured according to this specification to detect a stuck top pin using a pressure sensor having an inlet set or positioned in the landing pad within the reaction chamber. Figure 11 is a side sectional view of a pin assembly of this specification, such as a top pin used in the sensor assembly of Figure 10, and in the lower position. Figure 12 is a top perspective view of a portion of a reactor system, showing the interior space of a reaction chamber comprising three pin assemblies of Figure 11, each pin assembly being paired with a top pin.

Claims

1. A reactor system with a stuck top pin detection, comprising: a reaction chamber; a base for supporting a wafer in an interior space of the reaction chamber; a lift coupled to the base and configured to raise and lower the base in the interior space; a top pin supported by the base and extending vertically through the base to travel between an upper position and a lower position by moving the base via the lift; a landing pad for receiving a base of the top pin when the top pin is in the lower position; and a sensor assembly having a sensor at least partially located in the interior space of the reaction chamber, wherein an output signal of the sensor indicates whether the top pin is stuck or engaged during travel through the base.

2. The reactor system as claimed in claim 1, wherein the sensor assembly further includes a detection module that displays data based on the output signal of the sensor, or processes the output signal of the sensor, to detect when the top pin gets stuck or latches during its travel through the base.

3. The reactor system as claimed in claim 2, wherein the output signal provides a sensed temperature or pressure, and wherein the processing of the output signal by the detection module includes comparing the sensed temperature or pressure with a predetermined temperature or pressure disturbance related to the movement of the top pin that is not stuck or engaged, or includes comparing the timing of the sensed temperature or pressure with the movement of the elevator.

4. The reactor system as claimed in claim 1, further comprising a cover covering an upper surface of the base, wherein the sensor includes a temperature sensor located in a channel disposed in a body of the cover, thereby the output signal being correlated with a sensed temperature of the cover.

5. The reactor system as claimed in claim 4, wherein the temperature sensor comprises a thermocouple or a resistance temperature detector located near one of the central axes of the cover.

6. The reactor system as claimed in claim 5, wherein the temperature sensor includes a conduit extending away from the thermocouple or the resistance temperature detector for carrying the output signal, and wherein the conduit includes two or more coils in the interior space of the reaction chamber.

7. The reactor system as claimed in claim 4, wherein the temperature sensor comprises a thermocouple or a resistance temperature detector located at a radial distance from one edge of the lid, the radial distance being in the range of 40 mm to 60 mm.

8. The reactor system as claimed in claim 1, wherein the sensor includes a temperature sensor located within the landing pad, whereby the output signal is correlated with a sensed temperature of the landing pad.

9. The reactor system as claimed in claim 8, wherein the temperature sensor comprises a thermocouple or a resistance temperature detector located in a head of the landing pad, the head of the landing pad being adapted to receive the base of the top pin.

10. The reactor system of claim 1, wherein the sensor includes a gas inlet in the landing pad, a pressure sensor disposed outside the reaction chamber, and a flow line that fluidly couples the landing pad to the pressure sensor, wherein the output signal is correlated with a sensed pressure in the flow line.

11. The reactor system of claim 10, wherein the gas inlet is contained in an orifice in a head of the landing pad, wherein when the top pin is in the lower position, the base of the top pin blocks or impedes gas flow through the orifice, and wherein the sensor assembly further includes a gas pump coupled to the flow line, the gas pump being operable to extract gas from the interior space of the reaction chamber through the landing pad and the flow line.

12. A reactor system with a stuck top pin detection, comprising: a reaction chamber; a base having a cover and for supporting a wafer in an interior space of the reaction chamber; a lift for raising and lowering the base in the interior space; a top pin supported by the base and extending vertically through the base to travel between an upper position and a lower position by moving the base via the lift; a landing pad for receiving a base of the top pin when the top pin is in the lower position; and a sensor assembly including a temperature sensor positioned in a channel disposed in the cover, wherein an output signal of the temperature sensor provides a sensed temperature of the cover.

13. The reactor system as claimed in claim 12, wherein the sensor assembly further includes a detection module that displays temperature data of the lid based on the sensed temperature, or processes the sensed temperature to detect when the top pin gets stuck or latches during travel through the base.

14. The reactor system as claimed in claim 13, wherein the processing of the output signal by the detection module includes comparing the sensed temperature with a predetermined temperature disturbance related to the movement of the top pin that is not stuck or engaged, or includes comparing the timing of the sensed temperature with the movement of the elevator.

15. The reactor system as claimed in claim 12, wherein the temperature sensor comprises a thermocouple or a resistance temperature detector located near a central axis of the cover.

16. The reactor system of claim 12, wherein the temperature sensor includes a conduit extending away from the temperature sensor for carrying the output signal, and wherein the conduit includes two or more coils in the interior space of the reaction chamber.

17. The reactor system as claimed in claim 12, wherein the temperature sensor is located in a channel disposed in one body of the cover, wherein the temperature sensor comprises a thermocouple or a resistance temperature detector, which is positioned in the channel at a radial distance from one edge of the cover, the radial distance being in the range of 40 mm to 60 mm.

18. A method for monitoring the movement of a top pin in a reaction chamber, comprising: sensing a temperature of a base cover in an operating state of the reaction chamber using a temperature sensor; comparing the temperature of the base cover with a predetermined range of expected temperatures for the operating state of the reaction chamber; and generating an alert message or updating a graphical user interface (GUI) indicating a stuck top pin when the comparison result determines that the temperature of the base cover exceeds the predetermined range of expected temperatures.

19. The method as described in claim 18, wherein the operating state of the reaction chamber is related to dropping a wafer onto one of the upper surfaces of the base cover.

20. The method as described in claim 18, wherein the temperature sensor includes a thermocouple or a resistance temperature detector positioned within the base cover.

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