System and method for detecting wafer outgassing in vacuum load lock using residual gas sensor

Abstract

Disclosed herein is a system and method for detecting and / or minimizing outgassing contamination released from a sample into a tool, the system comprising: a tool configured to characterize a sample under test wherein operating conditions characterizing the tool include reaching a vacuum level of 10-6 torr or greater; a load lock chamber; and a time-of-flight residual gas analyzer (TOF-RGA) sensor in fluid flow communication with the load lock chamber, the TOF-RGA configured to provide a real-time measurement of a composition of a gas released from the sample under test into the load lock chamber.

Description

TECHNICAL FIELD

[0001] The present disclosure relates generally to the manufacturing and metrology of samples. BACKGROUND

[0002] Samples, such as but not limited to wafers and semiconductors, are typically manufactured and inspected within vacuum environments, such as those that occur in semiconductor device production processes. Tools that operate under vacuum conditions, including scanning electron microscopes (SEMs), are commonly used for sample characterization, where each sample is housed in a load lock chamber and transferred into a vacuum chamber of the tool. Insertion of samples into these tools typically requires gas pumping to achieve the required vacuum level. However, such samples typically undergo outgassing, i.e., emission of gases therefrom, for example including during the pumping process. Outgassing from the samples can result in tool contamination, cross-contamination between samples, tool health and performance degradation, and reduced high voltage immunity.

[0003] Accordingly, there is a need in the art for methods for rapidly detecting outgassing from samples prior to insertion into a high vacuum environment, i.e., in a load lock. SUMMARY

[0004] According to some embodiments of the present disclosure, aspects of the present disclosure relate to the manufacturing and metrology of samples.

[0005] More specifically, but not exclusively, according to some embodiments of the present disclosure, aspects of the present disclosure relate to the manufacturing and characterization of samples, such as wafers, photoresists, semiconductor devices, and / or components thereof.

[0006] Accordingly, according to an aspect of some embodiments, there is provided a system for detecting / minimizing outgassing contamination from a tested sample into a characterization tool.

[0007] Advantageously, according to some embodiments, the disclosed system facilitates minimizing outgassing contamination into a process chamber of a tool, thereby minimizing cross-contamination, and facilitating health and performance of the tool.

[0008] Advantageously, according to some embodiments, the disclosed system enables rapid outgassing detection.

[0009] Advantageously, according to some embodiments, the disclosed system enables differentiation between water and organic outgassing.

[0010] According to some embodiments, there is provided a system for detecting and / or minimizing outgassing contamination from a sample into a characterization tool, the system comprising:

[0011] a main chamber comprising a characterization tool configured to characterize a sample, wherein operating conditions of the characterization tool include reaching a vacuum level of up to 10 -5 tor or higher;

[0012] a load lock chamber configured to receive the sample;

[0013] a time-of-flight residual gas analyzer (TOF-RGA) sensor in fluid flow communication with the load lock chamber, wherein the TOF-RGA sensor is configured to provide real-time measurements of outgassing amounts released from a tested sample in the load lock chamber;

[0014] and a controller configured to receive measurements from the TOF-RGA sensor, to calculate the outgassing amounts detected in the load lock chamber and to trigger transfer of the sample from the load lock chamber to the main chamber only when the outgassing amounts detected in the load lock chamber are at or below a predetermined threshold, thereby reducing the risk of cross-contamination of other / next tested samples and facilitating maintenance of tool health, and to transfer the sample into the characterization chamber.

[0015] According to some embodiments, calculating the outgassing amounts includes calculating a sum of peaks in a predetermined range. According to some embodiments, the calculation includes distinguishing between water and organic outgassing,

[0016] According to some embodiments, the system further comprises a pump configured to generate a vacuum in the load lock chamber, and a pressure monitor configured to monitor pressure within the load lock chamber. According to some embodiments, the controller is configured to trigger measurements by the TOF-RGA sensor when a signal provided by the pressure monitor indicates that a first predetermined pressure level has been obtained. According to some embodiments, the controller is configured to trigger transfer of the sample when a signal provided by the pressure monitor indicates that a second predetermined pressure is substantially equal to a pressure in the main chamber, or when a signal provided by the pressure monitor indicates that a predetermined third threshold has been reached; or when a signal provided by the pressure monitor indicates that a predetermined amount of time has elapsed.

[0017] According to some embodiments, outgassing sensitivity of the TOF-RGA sensor is in the range of 10 -4 tor to 10 -10 tor.

[0018] According to some embodiments, the TOF-RGA sensor provides a measurement time of the composition of the gas of 30 seconds or less. According to some embodiments, the TOF-RGA sensor provides a measurement time of the composition of the gas of 5 seconds or less.

[0019] According to some embodiments, the TOF-RGA sensor provides a real-time measurement of the composition of the gas with a pressure of up to 10 -4 tor.

[0020] According to some embodiments, the TOF-RGA sensor is replaceable.

[0021] According to some embodiments, the characterization tool is selected from the group consisting of: a scanning electron microscope (SEM), a focused ion beam (FIB), a transmission electron microscope (TEM), a scanning probe microscope (SPM). Each possibility is a separate embodiment.

[0022] According to some embodiments, the tested sample includes photoresist or organic residues from a previous process step.

[0023] According to some embodiments, the controller is further configured to trigger an alarm if the outgassing amount exceeds the predetermined threshold for a predetermined amount of time.

[0024] According to some embodiments, there is provided a method for detecting and / or minimizing outgassing from a sample, the method comprising:

[0025] positioning a tested sample into a load lock chamber of a characterization tool;

[0026] activating a pump associated with the load lock chamber to achieve a first predetermined vacuum level in the load lock;

[0027] upon reaching the first predetermined vacuum level, performing a residual mass analysis by a TOF-RGA sensor fluidically connected to the load lock chamber to identify an amount of gas released from the tested sample into the load lock chamber; and

[0028] transferring the sample into a main chamber of the characterization tool only if the detected amount of gas is below a predetermined threshold, thereby reducing the risk of cross-contamination of other / next tested samples and facilitating maintaining tool health.

[0029] According to some embodiments, the method further comprises maintaining the tested sample in the load lock chamber for a predetermined amount of time if the detected amount of gas is above the predetermined threshold.

[0030] According to some embodiments, the sample is transferred into the main chamber of the characterization tool if the detected amount of the gas is at or below the predetermined threshold during the predetermined amount of time.

[0031] According to some embodiments, the sample is removed from the load lock chamber if the detected amount of the gas remains above the predetermined threshold during the predetermined amount of time.

[0032] According to some embodiments, calculating the outgassing amount includes calculating a sum of peaks in a predetermined range.

[0033] According to some embodiments, the sample is water.

[0034] Certain embodiments of the present disclosure can include some, all, or none of the advantages described above. One or more other technical advantages can be readily apparent to those skilled in the art in light of the attached drawings, descriptions, and claims. Moreover, while the above advantages have been enumerated for the embodiments, various embodiments can include all, some, or none of the enumerated advantages.

[0035] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. In the case of conflict, the patent specification, including definitions, will control. As used herein, the indefinite articles "a" and "an" mean "at least one" or "one or more," unless context clearly indicates otherwise. BRIEF DESCRIPTION OF DRAWINGS

[0036] Some embodiments of the present disclosure are described herein with reference to the accompanying drawings. The description, together with the drawings, makes apparent preferred Figure One enable those skilled in the art to practice some embodiments. The drawings are for purposes of illustration only and are not attempted to show structural details of embodiments in more detail than is necessary for a fundamental understanding of the embodiments. For purposes of clarity, not every component of some embodiments is shown in the drawings. In addition, two or more separate objects in the same drawing figure can be shown as a single object. In particular, some objects can be exaggerated in scale, while others can be omitted or simplified in scale. The drawings are intended to assist in understanding the principles of some embodiments.

[0037] In the drawings:

[0038] Figure 1 A block diagram of a system for detecting and / or minimizing outgassing contamination into a tool according to some embodiments is presented;

[0039] Figure 2 A flowchart of a method of inserting a sample into a vacuum system through a load lock according to some embodiments is presented;

[0040] Figure 3 is an example of an empirically derived plot of partial pressure as a function of mass-to-charge ratio in atomic mass units (amu) detected by a TOF-RGA sensor positioned on and in fluid flow communication with a vacuum chamber, in accordance with some embodiments; and

[0041] Figure 4 is an example of an empirically derived plot of partial pressure as a function of mass-to-charge ratio in atomic mass units (amu) detected by a quadrupole-RGA sensor positioned on and in fluid flow communication with a vacuum. DETAILED DESCRIPTION

[0042] The principles, uses and implementations of the teachings herein can be better understood with reference to the accompanying description and figures. Upon careful consideration of the present description and accompanying figures, one skilled in the art will be able to implement the teachings of the present disclosure without undue effort or experimentation.

[0043] According to an aspect of some embodiments, there is provided a system for detecting, controlling and / or minimizing organic outgassing contamination released from a sample into a tool, such as a characterization / metrology tool, a manufacturing tool, and the like.

[0044] According to an aspect of some embodiments, there is provided a method for detecting, controlling and / or minimizing organic outgassing contamination released into a tool, such as a characterization / metrology tool, a manufacturing tool, and the like.

[0045] According to an aspect of some embodiments, there is provided a method for manufacturing a semiconductor device, wherein the method includes detecting, controlling and / or minimizing organic outgassing contamination released into a tool.

[0046] Advantageously, in some embodiments, the disclosed system and method are configured to provide rapid analysis of outgassing released / emanated from a sample.

[0047] As used herein, the terms“sample” and“specimen” can be interchangeable, according to some embodiments.

[0048] As used herein, the term "sample" can refer to any specimen suitable for undergoing a process or inspection in a tool operation under vacuum environment, according to some embodiments. The term "sample" can refer to a semiconductor device and / or components / elements thereof, according to some embodiments. The term "sample" can refer to a wafer (e.g., Si wafer, GaAs wafer, etc.), a diode, a transistor, an integrated circuit, etc., and / or any components / elements thereof, according to some embodiments. The term "sample" can refer to an electronic device and / or components / elements thereof, according to some embodiments. The term "sample" can refer to an energy storage device or components / elements thereof, according to some embodiments. The term "sample" can refer to an optoelectronic device or any components / elements thereof, according to some embodiments. The term "sample" can refer to a photoresist, according to some embodiments.

[0049] In some embodiments, results of the outgassing analysis can be obtained in about 5 seconds or less. Thereby, in some embodiments, the disclosed systems and methods facilitate manufacturing processes of the sample while maintaining performance and health of the manufacturing / metrology tool. In some embodiments, the disclosed systems and methods can substantially not cause disruptions or hindrances to delay the manufacturing / metrology processes.

[0050] Advantageously, in some embodiments, the disclosed systems and methods are configured to distinguish between water and organic outgassing.

[0051] Advantageously, in some embodiments, the disclosed systems and methods have high sensitivity of outgassing detection. In some embodiments, the disclosed systems and methods are capable of detecting outgassing up to about 10 -5 Torr of outgassing. -10 Torr of outgassing.

[0052] Reference is made to Figure 1 which presents a block diagram of a system 100 for detecting, controlling and / or minimizing outgassing contamination from a sample into a tool, according to some embodiments. In some embodiments, the system 100 can be used for characterizing and / or manufacturing the sample.

[0053] The system 100 includes a characterization tool 102. According to some embodiments, the characterization tool 102 can include any type of characterization / metrology tool and / or process tool having operating conditions of vacuum levels up to about 10 -6 Torr or higher, about 10 -7 Torr or higher, about 10 -8 Torr or higher, and about 10 -9 Torr or higher. Each possibility is a separate embodiment.

[0054] According to some embodiments, the characterization tool 102 can include any type of characterization / metrology tool and / or process tool having a vacuum chamber and a load lock (i.e., a load lock chamber). According to some embodiments, the characterization tool 102 can include any tool type, including chambers that operate or are capable of reaching operating conditions in high vacuum (HV) and ultra-high vacuum (UHV) states.

[0055] In some embodiments, the characterization tool 102 can include a tool utilized in a process for manufacturing a sample. According to some embodiments, the characterization tool 102 can include a process tool configured to manufacture a semiconductor device or a component thereof. Alternatively, or additionally, in some embodiments, the characterization tool 102 can be configured to characterize a sample.

[0056] According to some embodiments, the characterization tool 102 can include a scanning electron microscope (SEM), a high resolution SEM (HR-SEM), a focused ion beam (FIB) setup, a transmission electron microscope (TEM), an X-ray photoelectron spectroscopy tool (XPS), an ultraviolet photoelectron spectroscopy (UPS) tool, any type of scanning probe microscope (SPM), etc. Each possibility is a separate embodiment. As one non-limiting example, the characterization tool 102 can include a scanning tunneling microscope (STM). Each possibility is a separate embodiment.

[0057] According to some embodiments, the characterization tool 102 can be configured to perform one or more manufacturing processes on a sample. According to some embodiments, the characterization tool 102 can be configured to deposit one or more features onto a sample.

[0058] According to some embodiments, the characterization tool 102 includes a main chamber 130. According to some embodiments, the main chamber 130 can include, among other things, a chemical vapor deposition (CVD) chamber, a physical vapor deposition (PVD) chamber, a plasma deposition chamber, an atomic layer deposition (ALD) chamber, a sputtering chamber, a thermal evaporation chamber. Each possibility is a separate embodiment. According to some embodiments, the processing tool and the characterization tool are separate tools.

[0059] According to some embodiments, the main chamber 130 can include a characterization chamber. As one non-limiting example, the main chamber 130 can include a vacuum chamber of a SEM, e.g., in which a sample under test is characterized / inspected.

[0060] In some embodiments, characterization tool 102 can optionally include or be in communication with an electron beam (e-beam) source. In some embodiments, main chamber 130 can optionally include one or more electron sensors / detectors. In some embodiments, main chamber 130 can include or be in communication with one or more additional sensors / detectors such as, but not limited to, optical sensors, electrical sensors, and the like or combinations thereof.

[0061] In some embodiments, characterization tool 102 can include a plurality of main chambers 130 (not depicted). In some embodiments, the plurality of main chambers 130 can include one or more characterization chambers and / or one or more process chambers or any combination thereof. Each possibility is a separate embodiment. As one non-limiting example, the plurality of main chambers 130 can include one characterization chamber and a plurality of process chambers.

[0062] In some embodiments, main chamber 130 of characterization tool 102 can be maintained at a vacuum level of about 10 -5 Torr or higher, about 10 -6 Torr or higher, about 10 -7 Torr or higher, about 10 -8 Torr or higher, and about 10 -9 Torr or higher. Each possibility is a separate embodiment. In some embodiments, main chamber 130 of characterization tool 102 can be maintained at a UHV state. In some embodiments, main chamber 130 of characterization tool 102 can be maintained at a vacuum level in a range from about 10 -5 Torr to about 10 -10 Torr.

[0063] According to some embodiments, and as Figure 1 schematically depicted, main chamber 130 includes a worktable 150 configured to house a sample 152. In some embodiments, worktable 150 can be movable.

[0064] In some embodiments, sample 152 is configured to undergo at least one process and / or analysis in characterization tool 102 such as, but not limited to, a characterization / inspection process, a fabrication process such as, but not limited to, a deposition process, an etching process, and the like, or combinations thereof.

[0065] In some embodiments, the characterization tool 102 includes a vacuum pump 120 configured to reduce pressure within the characterization tool 102. According to some embodiments, a load lock chamber 110 is further included, configured to receive the sample 152 prior to its arrival to the main chamber 130. According to some embodiments, the load lock chamber 110 can be connected to the main chamber 130 via a sealed door 113. According to some embodiments, the load lock chamber 110 includes a sample holder 112 configured to hold the sample 152. The load lock chamber 110 is associated with a second vacuum pump 124 configured to reduce vacuum in the load lock chamber 110.

[0066] Once the sample 152 is loaded into the load lock chamber 110, the pressure therein can be reduced to a first predefined value by the vacuum pump 124.

[0067] According to some embodiments, the characterization tool 102 includes a time of flight residual gas analyzer (TOF-RGA) sensor 140. According to some embodiments, the TOF-RGA sensor 140 can be positioned at any positioning / location on the load lock chamber 110. According to some embodiments, the TOF-RGA sensor 140 is in constant gas flow connection with the load lock chamber 110. According to some embodiments, measurements by the TOF-RGA sensor 140 can be initiated upon reaching the first predefined pressure level, e.g., via a command received from the controller 160. According to some embodiments, the first predefined pressure value is in the range of about 10 -3 Torr to about 10 -4 Torr. In some embodiments, the pressure within the load lock chamber 110 can be further reduced to be substantially equal to the pressure maintained within the main chamber 130 (e.g., between about 10 -5 Torr to about 10 -8 Torr), optionally, while the TOF-RGA sensor 140 continues to measure.

[0068] According to some embodiments, the TOF-RGA sensor 140 is configured to provide real-time measurements of the composition of gases released from the sample 152. According to some embodiments, the TOF-RGA sensor 140 provides measurements of the composition of gases released from the sample in the range of about 1 second to about 5 seconds, about 1 second to about 10 seconds, about 1 second to about 20 seconds, and about 1 second to about 30 seconds. Each possibility is a separate embodiment.

[0069] According to some embodiments, the measurement time of the TOF-RGA sensor 140 to provide a composition of the gases released from the sample can be about 30 seconds or less, about 20 seconds or less, about 10 seconds or less, about 5 seconds or less, about 4 seconds or less, about 3 seconds or less, about 2 seconds or less, about 1 second or less. Each possibility is a separate embodiment.

[0070] In some embodiments, the sampling rate of the TOF-RGA sensor 140 to acquire a substantially complete mass spectrum of the gases released from the sample 152 into the load lock 110 can be up to about 250 milliseconds. According to some embodiments, utilizing the system 100 in a production line, such as in a manufacturing process of semiconductor devices, can be substantially free of throughput time disruptions / obstructions.

[0071] According to some embodiments, the TOF-RGA sensor 140 is configured to distinguish between water / hydrated outgassing and organic outgassing. Thereby, in some embodiments, the risk of cross-contamination of other / following samples is reduced, and maintaining the health and performance of the characterization tool 102 is facilitated.

[0072] In some embodiments, the TOF-RGA sensor 140 can be configured to monitor peaks of specific gas molecules. Alternatively, or additionally, in some embodiments, the TOF-RGA sensor 140 can be configured to monitor a range of peaks above a predefined value and / or and, for example, as Figure 3 depicted. As one non-limiting example, the TOF-RGA sensor 140 can have a mass range of about 1 amu to 300 amu, and can be configured to sum substantially all predefined contaminants detected in the load lock chamber within a predefined range of the mass range of the TOF-RGA sensor.

[0073] In some embodiments, monitoring and / or detecting a range of peaks can advantageously reduce the detection time of the TOF-RGA sensor 140 for outgassing. In some embodiments, the on / off switching of the TOF-RGA sensor 140 can be fast, for example, in a range of about 2 seconds to 5 minutes, between 1 second to 1 minute, or between 1 second and 30 seconds. Each possibility is a separate embodiment. Thereby, in some embodiments, a rapid vent to pump recovery is facilitated, and in turn, the turnaround time for outgassing detection between samples is optimized. In some embodiments, the TOF-RGA sensor 140 can provide a high sampling rate of up to about 250 milliseconds to acquire a substantially complete outgassing mass spectrum.

[0074] In some embodiments, the on / off switching of the TOF-RGA sensor 140 (i.e., the vent to pump recovery time between samples) can be 7 seconds to 5 minutes.

[0075] According to some embodiments, the residual mass analysis can include monitoring peaks having a predefined value for one or more of the specific gas composition (e.g., specific gas molecules), e.g., as Figure 4 depicted. Thereby, in some embodiments, materials released / evolved from the sample are distinguished. Alternatively, or additionally, in some embodiments, the residual mass analysis can include monitoring the sum of the range of peaks above a predefined value. Each possibility is a separate embodiment.

[0076] According to some embodiments, the TOF-RGA sensor 140 provides real-time measurements of the composition of the gas having a pressure of up to about 10 -4 Torr.

[0077] According to some embodiments, the outgassing detection capability / sensitivity of the TOF-RGA sensor 140 is in the range of about 10 -4 Torr to about 10 -10 Torr. According to some embodiments, the outgassing capability / sensitivity of the TOF-RGA sensor 140 is in the range of about 10 -4 Torr to about 10 -10 Torr, about 10 -5 Torr to about 10 -10 Torr, about 10 -5 Torr to about 10 -7 Torr, about 10 -5 Torr to about 10 -8 Torr, about 10 -6 Torr to about 10 -10 Torr, about 10 -7 Torr to about 10 -10 Torr, about 10 -8 Torr to about 10 -10 Torr, about 10 -9 Torr to about 10 -10 Torr. Each possibility is a separate embodiment.

[0078] In some embodiments, the TOF-RGA sensor 140 provides gas analysis at a pressure range of substantially about 10 -3 Torr to about 10 -4 Torr. Each possibility is a separate embodiment.

[0079] In some embodiments, the TOF-RGA sensor 140 can be replaceable.

[0080] Advantageously, in some embodiments, the TOF-RGA sensor 140 enables detection of outgassing from the sample 152 in the load lock chamber 110 prior to entry of the sample 152 into the main chamber 130, thereby enabling opening of the door 113 between the load lock chamber 110 and the main chamber 130 only when the detected outgassing is reduced to at or below a predefined pressure. Thus, in some embodiments, outgassing in the main chamber 130 is minimized and / or avoided, thereby reducing / minimizing the risk of high voltage immunity reduction and improving the health and / or performance of the tool.

[0081] According to some embodiments, the characterization chamber 102 can include a pressure monitor 142 configured to monitor pressure (i.e., vacuum level). In some embodiments, the pressure monitor 142 can be configured to monitor pressure in the load lock chamber 110.

[0082] According to some embodiments, the controller 160 is configured to control operation of the system 100. More specifically, in some embodiments, the controller 160 can be configured to control and / or synchronize operation and / or functionality of one or more of the following: the load lock chamber 110, the main chamber 130, opening / closing of the door 113, the vacuum pump 120, the TOF-RGA sensor 140, and / or the workbench 150.

[0083] According to some embodiments, the controller 160 can be further configured to alarm, e.g., alarm a user, a different system or component, upon detecting a sum of ranges of peaks that are higher than a predefined value.

[0084] According to some embodiments, the controller 160 can output instructions, e.g., to a user, a different system or component. According to some embodiments, the instructions can include, among other things, transferring the sample into the main chamber of the tool. According to some embodiments, the instructions can include, among other things, removing the sample from the load lock chamber without transferring the sample into the main chamber of the tool. According to some embodiments, the instructions can include, among other things, a timeout alarm, as detailed elsewhere herein.

[0085] According to an aspect of some embodiments, there is provided a method for detecting outgassing from a sample. Reference is made to Figure 2 FIG. 2 shows a flowchart 200 of a method for detecting and / or minimizing outgassing, according to some embodiments. According to some embodiments, the method can include a process for manufacturing a semiconductor device, wherein outgassing is detected. According to some embodiments, the method can include characterizing a sample, such as but not limited to a semiconductor device. Each possibility is a separate embodiment.

[0086] According to some embodiments, at step 202, the method includes positioning / loading the sample into a load lock chamber of a characterization tool. In some embodiments, the characterization tool can include, among other things, a SEM, a FIB, a TEM, an XPS, an UPS, an SPM (e.g., an STM), etc. Each possibility is a separate embodiment. Alternatively, or additionally, in some embodiments, the characterization tool can include a process / fabrication tool. According to some embodiments, the process / fabrication tool can include a deposition chamber / tool, such as, but not limited to, a CVD chamber / tool, a PVD chamber / tool, a plasma deposition chamber / tool, an ALD chamber / tool, a sputtering chamber / tool, a thermal evaporation chamber / tool, an etching chamber / tool, a cleaning chamber / tool, etc., or any combination thereof. Each possibility is a separate embodiment. As one non-limiting example, the process / fabrication tool can include a wafer fabrication tool. As another non-limiting example, the process / fabrication tool can include a semiconductor device fabrication tool / chamber.

[0087] According to some embodiments, at step 204, the method includes periodically initiating pumping and venting to achieve a predetermined vacuum level in the load lock chamber. According to some embodiments, the predetermined vacuum level can be substantially equal to a vacuum level maintained in a main chamber of the tool to facilitate operation of the main chamber and / or the tool. Alternatively, in some embodiments, the predetermined vacuum level can be lower than a vacuum level maintained in a main chamber of the tool.

[0088] According to some embodiments, the pumping and venting can be performed by a vacuum pump of the tool.

[0089] According to some embodiments, step 204 can optionally include monitoring the pressure / vacuum level in the load lock chamber by a pressure monitor of the tool. In some embodiments, the pressure monitor can take one or more measurements while the sample is positioned within the load lock chamber.

[0090] According to some embodiments, the sample can spontaneously outgas while positioned within the load lock chamber of the tool. According to some embodiments, the sample can outgas during the pumping and venting process.

[0091] According to some embodiments, at step 206, the method includes performing residual mass analysis by the TOF-RGA sensor to identify, in real-time, a composition of gases released / emanated from the sample while being maintained within the load lock chamber of the tool.

[0092] According to some embodiments, the residual mass analysis can include monitoring peaks having a predefined value for one or more of a particular gas composition (e.g., a particular gas molecule). Alternatively, or additionally, in some embodiments, the residual mass analysis can include monitoring a sum of a range of peaks above a predefined value. Each possibility is a separate embodiment.

[0093] In some embodiments, monitoring and / or detecting the range of peaks can advantageously reduce the detection time of outgassing by the TOF-RGA sensor. In some embodiments, the on / off switching of the TOF-RGA sensor and the subsequent stabilization / equilibration can be fast, e.g., in the range of about 2 seconds to 5 minutes, typically in the range of 2 seconds to 1 minute, or in the range of 2 seconds to 30 seconds. Each possibility is a separate embodiment.

[0094] According to some embodiments, step 206 can further include distinguishing, by the TOF-RGA sensor, water from organic outgassing released from the sample into the load lock chamber in real time. In some embodiments, detecting the composition of the gases released / evolved from the sample can include detecting the partial pressure of each of the gases that have been released / evolved, thereby enabling its detection and identification.

[0095] According to some embodiments, if no organic outgassing is detected, or if the organic outgassing is below a predetermined threshold, the method can optionally include step 208a, transferring the sample to a main chamber for inspection. According to some embodiments, the instructions to include transferring the sample to a main chamber of the tool can be based at least in part on one or more of: detecting a predefined level of outgassing by the TOF-RGA sensor, detecting a substantially insignificant level of outgassing, determining that the outgassing from the sample is substantially free of undesirable gases based on analysis by the TOF-RGA sensor, and the like or any combination thereof. As one non-limiting example, step 208a can optionally include detecting, based at least in part on the TOF-RGA sensor, that the sample has substantially reached a steady state (i.e., the sample has substantially completed outgassing) and / or reached a substantially insignificant outgassing level from the steady state.

[0096] According to some embodiments, if organic outgassing is detected and / or above a predetermined threshold, the method can optionally include step 208b, maintaining the sample in the load lock chamber for a predetermined amount of time (timeout), such as up to 5 minutes or up to 2 minutes.

[0097] During the timeout, at step 210, the TOF-RGA sensor continues to perform residual mass analysis. If no further organic outgassing is detected during or at the completion of the timeout, the method can optionally include step 212a, transferring the sample to a main chamber for inspection.

[0098] According to some embodiments, if no further organic outgassing is detected or is below a predetermined threshold level, the method can optionally include step 212a, transferring the sample to a main chamber for inspection.

[0099] Alternatively, if organic gas release is still detected and / or exceeds a predetermined threshold, the method may include step 212b, i.e., removing the sample from the loading lock chamber without transferring it to the main chamber. According to some embodiments, one or more undesirable gases may, among others, include organic gas releases, such as, but not limited to, hydrocarbon gas releases, or any combination thereof. Additionally or alternatively, if organic gas release is still detected and / or exceeds a predetermined threshold, the method may include step 212c, i.e., issuing an alarm, such as an audible alarm or an output message alarm.

[0100] Example

[0101] refer to Figure 3 Graph 300 shows an empirically obtained curve of partial pressure as a function of atomic mass units (amu), detected by a TOF-RGA sensor positioned in a vacuum chamber. The tested samples included those similar to those at approximately 2e -6 Organic pollutants released from photoresist under pressure were examined.

[0102] The TOF-RGA sensor utilized has a mass range of approximately 1 amu to 300 amu. As depicted in graph 300, while the characteristic signal of a specific substance released / emitted from the test sample cannot be easily observed by detecting the release of gas in the loading lock chamber, the TOF-RGA sensor can identify the sum of the released gas values ​​that have reached a predetermined threshold, such as approximately 50 amu or higher (schematically labeled "Σ = contamination"). In other words, in some embodiments, released contamination can be defined as a gas or any other substance having a range of peaks at approximately 50 amu and higher. Gases detected at 50 amu and higher include hydrocarbon contamination. That is, by utilizing the TOF-RGA sensor, rapid detection of the superposition of organic / hydrocarbon contamination released / emitted from the test sample is achieved, thereby advantageously minimizing cross-contamination between different samples and promoting tool health without extending measurement downtime during production.

[0103] refer to Figure 4 The graph 400 shows an empirically obtained partial pressure as a function of amu, detected by a quadrupole RGA sensor positioned in a vacuum chamber. The tested sample included organic contaminants similar to photoresist.

[0104] The quadrupole RGA sensor used in the experimental setup has a mass range of approximately 1 amu to 300 amu. For example... Figure 4As depicted, the quadrupole RGA sensor is characterized by high sensitivity to outgassing detection. In other words, as seen, the empirically obtained plot 400 provides a characteristic signal of the species released / emanated from the sample under test. However, the higher sensitivity comes at the expense of a prolonged equilibration period, which disrupts production time and cost, while in most cases, knowing the exact species of outgassing is typically not necessary.

[0105] In the specification and claims of this application, the words "comprise" and "contain" and variations thereof, are not meant to be limiting, and do not exclude the presence of elements other than those listed.

[0106] As used herein, the term "about" can be used in reference to a value or parameter (e.g., a length of an element) to indicate that the value or parameter is within a continuous range of values including the given value or parameter. According to some embodiments, "about" can indicate that the value or parameter is within 80% and 120% of the given value. For example, a statement that a length of an element is equal to about 1 m is equivalent to a statement that the length of the element is between 0.8 m and 1.2 m. According to some embodiments, "about" can indicate that the value or parameter is within 90% and 110% of the given value. According to some embodiments, "about" can indicate that the value or parameter is within 95% and 105% of the given value.

[0107] As used herein, according to some embodiments, the terms "substantially" and "about" can be interchangeable.

[0108] It will be appreciated that certain features of the disclosure, which are, for clarity, described in the context of separate embodiments, can also be provided in combination in a single embodiment. Conversely, various features of the disclosure, which are, for brevity, described in the context of a single embodiment, can also be provided separately or in any suitable

[0109] Although the stages of the methods according to some embodiments can be described in a particular sequence, the methods of the disclosure can include some or all of the described stages performed in a different order. The methods of the disclosure can include several of the described stages or all of the described stages. Unless explicitly stated otherwise, a particular stage in a disclosed method should not be considered an essential stage of that method.

[0110] While the disclosure has been described in connection with specific embodiments thereof, it will be understood that many modifications, variations and alternatives will be apparent to those skilled in the art. It is intended to cover all such modifications, variations and alternatives included within the scope of the appended claims. It will be understood that the disclosure is not necessarily limited in its application to the details of construction and the arrangement of components and / or methods set forth herein. Other embodiments are capable of being practiced and are encompassed within the scope of the disclosure.

[0111] The phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting. The reference to any prior art in this application is not, and should not be taken as, an acknowledgment or any form of suggestion that this prior art forms part of the common general knowledge. Headings of sections are used herein for ease of reference only and do not limit the scope of the examples described in that section or the disclosure in general.

Claims

1. A system for detecting and / or minimizing gaseous contaminants released from a sample into a characterization tool, the system comprising: A main chamber, the main chamber including a characterization tool configured to characterize a sample, wherein the operating conditions of the characterization tool include reaching 10 -5 A vacuum level of Turbo or higher; A loading and locking chamber is configured to receive the sample; A time-of-flight residual gas analyzer (TOF-RGA) sensor is in fluid communication with the loading lock chamber, wherein the TOF-RGA sensor is configured to provide a real-time measurement of the amount of gas released from the test sample in the loading lock chamber; And a controller configured to receive measurements from the TOF-RGA sensor, calculate the amount of gas released detected in the loading lock chamber, and trigger the transfer of the sample from the loading lock chamber to the main chamber only when the amount of gas released detected in the loading lock chamber is at or below a predetermined threshold, thereby reducing the risk of cross-contamination of other / subsequent test samples and promoting the maintenance of tool health. The sample is then transferred to the characterization chamber.

2. The system of claim 1, wherein calculating the amount of gas released includes calculating the sum of peaks within a predetermined range.

3. The system of claim 2, wherein the calculation includes distinguishing between water and organic gas release.

4. The system of claim 1, further comprising: A pump configured to generate a vacuum in the loading locking chamber, and a pressure monitor configured to monitor the pressure within the loading locking chamber.

5. The system of claim 4, wherein the controller is configured to trigger a measurement by the TOF-RGA sensor when a signal provided by the pressure monitor indicates that a first predetermined pressure level has been obtained.

6. The system of claim 4, wherein the controller is configured to trigger the transfer of the sample when: a signal provided by the pressure monitor indicates that a second predetermined pressure is substantially equal to the pressure in the main chamber; or when a signal provided by the pressure monitor indicates that a predetermined third threshold has been reached; or when a signal provided by the pressure monitor indicates that a predetermined amount of time has elapsed.

7. The system of claim 1, wherein the release sensitivity of the TOF-RGA sensor is within 10... -4 Up to 10 -10 Within the scope of the trust.

8. The system of claim 1, wherein the TOF-RGA sensor provides a measurement time of 30 seconds or less for the composition of the gas.

9. The system of claim 1, wherein the TOF-RGA sensor provides a measurement time of 5 seconds or less for the composition of the gas.

10. The system of claim 1, wherein the TOF-RGA sensor provides up to 10 -4 Real-time measurement of the composition of the gas under pressure.

11. The system of claim 1, wherein the TOF-RGA sensor is replaceable.

12. The system of claim 1, wherein the characterization tool is selected from: scanning electron microscopy (SEM), focused ion beam microscopy (FIB), transmission electron microscopy (TEM), and scanning probe microscopy (SPM).

13. The system of claim 1, wherein the tested sample comprises photoresist or organic residues from previous process steps.

14. The system of claim 1, wherein the controller is further configured to trigger an alarm if the amount of gas released exceeds the predetermined threshold for a predetermined time.

15. A method for detecting and / or minimizing gas release from a sample, the method comprising: The sample to be tested is positioned in the loading and locking chamber of the characterization tool; Start the pump associated with the loading locking chamber to achieve a first predetermined vacuum level in the loading locking member; When the first predetermined vacuum level is reached, a residual mass analysis is performed by a TOF-RGA sensor fluidly connected to the loading lock chamber to identify the amount of gas released from the test sample into the loading lock chamber; as well as The sample is transferred to the main chamber of the characterization tool only when the detected gas amount is below a predetermined threshold, thereby reducing the risk of cross-contamination of other / subsequent test samples and promoting the maintenance of tool health.

16. The method of claim 15, further comprising maintaining the test sample in the loading lock chamber for a predetermined time if the detected gas quantity is higher than the predetermined threshold.

17. The method of claim 16, wherein if the amount of gas detected during the predetermined time period is at or below the predetermined threshold, the sample is transferred to the main chamber of the characterization tool.

18. The method of claim 16, wherein if the detected amount of gas remains above the predetermined threshold during the predetermined time period, the sample is removed from the loading lock chamber.

19. The method of claim 15, wherein calculating the amount of gas released includes calculating the sum of peaks within a predetermined range.

20. The method of claim 15, wherein the sample is water.

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