Method and system for monitoring gaseous molecular pollutants

Abstract

A method and system for monitoring gaseous molecular contaminants include a condensation shock bottle and a heating shock bottle, each filled with a sample liquid. A cooler is used to cool the condensation shock bottle below room temperature. A heater is used to heat the heating shock bottle above room temperature. A first tube is connected between the condensation shock bottle and the heating shock bottle. A second tube is inserted into the sample liquid in the heating shock bottle. An air pump is connected to the condensation shock bottle and pumps air, causing the second tube to draw the gas to be monitored and introduce it into the sample liquid in the heating shock bottle.

Description

Technical Field

[0001] The present disclosure relates to a method and system for monitoring gaseous molecular pollutants. Background Art

[0002] The semiconductor integrated circuit (IC) industry has experienced exponential growth. Technological advances in IC materials and design have produced generations of ICs, each with smaller and more complex circuits than the previous one. Over the course of IC evolution, functional density (i.e., the number of interconnected components per chip area) has generally increased, while geometry size (i.e., the smallest component (or wire) that can be formed) has generally decreased. This reduction generally increases production efficiency and reduces associated costs, but it also increases the complexity of processing and manufacturing the ICs. Summary of the Invention

[0003] According to some embodiments of the present disclosure, a method for monitoring gaseous molecular contaminants includes the following steps: A first sample liquid and a second sample liquid are added to a heated shock bottle and a condensing shock bottle, respectively. A first tube extends from the heated shock bottle into the heated shock bottle and further into the first sample liquid. A second tube is connected in series with the heated shock bottle and the condensing shock bottle. An air pump is connected to the condensing shock bottle to draw air, causing the first tube to draw a gas to be monitored and introduce it into the first sample liquid. The heated shock bottle is heated, causing the first sample liquid to evaporate and pass through the second tube to be collected by the condensing shock bottle.

[0004] According to some embodiments of the present disclosure, a method for monitoring gaseous molecular contaminants includes the following steps: A first sample liquid and a second sample liquid are added to a first impinger bottle and a second impinger bottle, respectively; a first tube extends from outside the first impinger bottle into the first impinger bottle and further into the first sample liquid; and a second tube is connected in series between the first impinger bottle and the second impinger bottle. The second impinger bottle is cooled. An air pump connected to the second impinger bottle is used to draw air, causing the first tube to draw a gas to be monitored and introduce it into the first sample liquid.

[0005] According to some embodiments of the present disclosure, a system for monitoring gaseous molecular contaminants includes the following components: a heated shock bottle filled with a first sample liquid; a condensed shock bottle filled with a second sample liquid; a heater for heating the heated shock bottle to a temperature above room temperature; a first tube connected between the heated shock bottle and the condensed shock bottle; a second tube inserted into the heated shock bottle; and an air pump connected to the condensed shock bottle. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] The aspects of the present disclosure are best understood from the following detailed description when read in conjunction with the accompanying drawings. It should be noted that, in accordance with standard industry practice, various features are not drawn to scale. In fact, the dimensions of the various features may be arbitrarily increased or reduced for clarity of discussion.

[0007] Figure 1 is a schematic diagram of a system for monitoring gaseous molecular pollutants according to some embodiments of the present disclosure;

[0008] Figure 2 is a schematic diagram of a system for monitoring gaseous molecular pollutants according to some embodiments of the present disclosure;

[0009] Figure 3 is a schematic diagram of a system for monitoring gaseous molecular pollutants according to some embodiments of the present disclosure;

[0010] Figure 4 is a schematic diagram of a system for monitoring gaseous molecular pollutants according to some embodiments of the present disclosure;

[0011] Figure 5 FIG. 4 is a flow chart of a method for monitoring gaseous molecular pollutants according to some embodiments of the present disclosure.

[0012]

Explanation of symbols

[0013] 400: Monitoring system for gaseous molecular pollutants

[0014] 400a: Monitoring system for gaseous molecular pollutants

[0015] 400b: Monitoring system for gaseous molecular pollutants

[0016] 400c: Monitoring system for gaseous molecular pollutants

[0017] 402: Condensation shock bottle

[0018] 403: Top cover

[0019] 404: Sampling liquid

[0020] 406: Pipe body

[0021] 406a: End

[0022] 406b: End

[0023] 408: Pipe body

[0024] 408a: End

[0025] 410: Air Pump

[0026] 412: Cooler

[0027] 413: Heating shock bottle

[0028] 414: Sampling liquid

[0029] 415: Top cover

[0030] 416:tube body

[0031] 416a: End

[0032] 416b: End

[0033] 418: Heater

[0034] 450: Heat insulation board

[0035] 452: Thermal insulation box

[0036] 454: Thermal insulation box

[0037] 500:Method

[0038] 502: Operation

[0039] 504: Operation

[0040] 506: Operation

[0041] 508: Operation

[0042] 510: Operation DETAILED DESCRIPTION

[0043] The following disclosure provides many different embodiments or examples for implementing the different features of the provided subject matter. Specific examples of components and arrangements are described below to simplify the present disclosure. Of course, these are merely examples and are not intended to be restrictive. For example, in the following description, a first feature formed on or above a second feature may include an embodiment in which the first feature and the second feature are formed to be in direct contact, and may also include an embodiment in which an additional feature may be formed between the first feature and the second feature so that the first feature and the second feature may not be in direct contact. In addition, the present disclosure may repeat element symbols and / or letters in various examples. This repetition is for simplicity and clarity purposes, and does not itself represent the relationship between the various embodiments and / or configurations discussed.

[0044] Additionally, for ease of description, spatially relative terms such as "below," "beneath," "lower," "above," "upper," and the like may be used herein to describe the relationship of one element or feature to another (other) element or feature as depicted in the figures. These spatially relative terms are intended to encompass different orientations of the elements in use or operation in addition to the orientation depicted in the figures. The device may be oriented in other ways, and the spatially relative descriptors used herein should likewise be interpreted accordingly.

[0045] In some embodiments, the methods and systems for monitoring gaseous molecular contaminants described herein are used to monitor five major categories of gaseous molecular contaminants: acids, bases, condensables, dopants, and metals. Acids are corrosive substances, such as hydrofluoric acid, sulfuric acid, hydrochloric acid, nitric acid, phosphoric acid, and hydrobromic acid. Bases are corrosive substances, such as ammonia, ammonium hydroxide, methylamine, dimethylamine, and diethanolamine. Dopants are chemical elements that can alter the electrical properties of semiconductor materials, such as boron (B), phosphorus (P), and arsenic (S). Condensables are substances other than water that have a boiling point greater than room temperature at atmospheric pressure and are capable of condensing on clean surfaces. Metal contaminants can arise from the use of copper in the manufacturing process. Metal compounds that exist in gaseous form or have a particle size smaller than that captured by high-efficiency particulate air (HEPA) filters can also become contaminants.

[0046] As semiconductor integrated circuit manufacturing processes have been miniaturized to the nanometer scale and continue to shrink, the impact of gaseous molecular contaminants on the quality, reliability, and yield of semiconductor integrated circuits continues to increase. For example, prolonged exposure of the surface of a finished wafer to fluorine / chlorine-containing air can cause surface aluminum corrosion; copper-processed wafers can also be corroded by sulfides; the stainless steel surface of the tooling machine can be corroded by prolonged exposure to fluorine / chlorine-containing air, generating particles; gaseous molecules react with each other to produce particles that deposit on the mask surface, or cause hazing on the projector lens, affecting exposure power or causing pattern variation; gaseous molecular contaminants adsorbed on the wafer surface can diffuse to the bottom through subsequent thermal processes, thereby altering the product's electrical properties. Therefore, some embodiments of the present disclosure propose the following solutions to monitor gaseous molecular contaminants.

[0047] Please refer to Figure 1, which illustrates a schematic diagram of a system for monitoring gaseous molecular contaminants according to some embodiments of the present disclosure. The system 400 for monitoring gaseous molecular contaminants includes a condensation shock bottle 402, a cooler 412, a heating shock bottle 413, a heater 418, and an air pump 410. Both the condensation shock bottle 402 and the heating shock bottle 413 are used to hold sample liquids (404, 414). A tube 406 is connected between the condensation shock bottle 402 and the heating shock bottle 413. For example, one end 406a of the tube 406 passes through the top cap 415 of the heating shock bottle 413 and is inserted into the heating shock bottle 413 (this end 406a of the tube 406 is not inserted into the sample liquid 414), and the other end 406b of the tube 406 passes through the top cap 403 of the condensation shock bottle 402 and is inserted into the sample liquid 404 in the condensation shock bottle 402. One end 416b of tube 416 passes through the top cap 415 of heated impinger bottle 413 and is inserted into sample liquid 414. The other end 416a of tube 416 is positioned outside heated impinger bottle 413, thereby introducing the gas to be monitored. Air pump 410 utilizes tube 408, which passes through the top cap 403 and connects to the interior of condensation impinger bottle 402 (the bottom end 408a of tube 408 is not inserted into sample liquid 404). This pump begins pumping air, causing the internal pressures of condensation impinger bottle 402 and heated impinger bottle 413 to decrease, allowing tube 416 to introduce the gas to be monitored into sample liquid 414. The gas to be monitored is then introduced into sample liquid 404 through tube 406. In some embodiments, one end 416b of tube 416 is positioned near the bottom of heated impinger bottle 413, allowing the gas to be monitored to continue to be introduced even as the sample liquid 414 gradually decreases in level due to evaporation from heat. In some embodiments, one end 416b of the tube 416 abuts the bottom of the heated shock bottle 413, allowing the monitored gas to be continuously introduced even as the sample liquid 414 evaporates and the liquid level gradually decreases. In some embodiments, the materials of the condensation shock bottle, heated shock bottle, and each tube may include plastic, metal, glass, or the like. In some embodiments, the tubes 406 and 408 are airtightly joined to the top cover 403 to prevent air leakage that affects the efficiency of gas extraction and sampling. In some embodiments, the tubes 406 and 416 are airtightly joined to the top cover 415 to prevent air leakage that affects the efficiency of gas extraction and sampling.

[0048] System 400 for monitoring gaseous molecular contaminants incorporates a heated impinger bottle 413 and a heater 418 to enhance sampling efficiency through heating and humidification. During sampling in system 400, cooler 412 cools condensing impinger bottle 402 to below room temperature, while heater 418 heats heated impinger bottle 413 above room temperature, increasing the saturation ratio of the sampled liquid for the gaseous molecular contaminants. In some embodiments, cooler 412 cools condensing impinger bottle 402 to the freezing point of the sampled liquid, while heater 418 heats heated impinger bottle 413 to a temperature between 60°C and 65°C.

[0049] System 400 for monitoring gaseous molecular contaminants is designed with a two-stage sampling process. The first stage utilizes a heated shock vial 413 and heater 418 to increase the enthalpy of the sample liquid. The second stage utilizes a condensing shock vial 402 and cooler 412 to adiabatically cool the sample vapor, causing it to supersaturate and convert to a liquid state using the gaseous molecular contaminants as condensation nuclei. At the end of the sampling period, the sample liquid in the heated shock vial 413 of the first stage is heated and evaporated and transferred to the condensing shock vial 402 of the second stage. In other words, at the end of the sampling period, the sample liquid in the heated shock vial 413 has been completely evaporated, and the sample liquid collected in the condensing shock vial 402 of the second stage is directly supplied to an inductively coupled plasma mass spectrometer for subsequent analysis.

[0050] In some embodiments, heater 418 can be an electromagnetic heater, an infrared heater, a resistive heater, a ceramic heater, a hot air heater (a fan heater or a blower heater), an electric heating tube heater (e.g., a hot plate heater, a flange heater, a fin heater, or an immersion heater), an electric radiant heater (e.g., a quartz halogen heater, a white quartz radiant tube, a blackbody radiant tube, or a gold-plated figure-eight tube), a heating plate heater (e.g., a mica heater, a silicone heater, a ceramic heater, a fiberglass heating tape, or an etched heater), a cast heater (e.g., a cast copper or cast aluminum heater), or similar heating devices. Heater 418 can directly heat impingement bottle 413 to achieve higher heating efficiency, or heater 418 can heat impingement bottle 413 through a water barrier to achieve a more stable temperature. In some embodiments, cooler 412 can be a refrigerator containing thermoelectric cooling chips of varying sizes or a similar cooling device. The cooler 412 can directly cool down the condenser impingement bottle 402 to obtain a higher cooling efficiency, or the cooler 412 can cool down the condenser impingement bottle 402 through water to obtain a more stable temperature.

[0051] In some embodiments, the warming shock bottle 413 and the condensing shock bottle 402 should be separated by a sufficient distance, and / or the cooler 412 and the heater 418 should be separated by a sufficient distance to avoid mutual heating and cooling processes affecting each other.

[0052] Experiments have confirmed that, under the same clean room conditions, the gaseous molecular contaminants in the clean room were sampled using the gaseous molecular contaminant monitoring system 400 and the sampling wafer for comparison. After the sampling wafer was sampled for a predetermined time, it was then pickled with hydrofluoric acid to extract a sampled water sample, which was then analyzed using an inductively coupled plasma mass spectrometer (a blank background wafer control was also sampled for comparison). If the sampling efficiency of the gaseous molecular contaminant monitoring system 400 was compared with the sampling efficiency of the sampling wafer (ppb / hr), the improvement was more than approximately 32 times for boron, more than approximately 5 times for phosphorus, and more than approximately 7 times for arsenic. The gaseous molecular contaminant monitoring system 400 not only improves the sampling concentration value, but also completes the sampling in a shorter time, which is conducive to immediate response and control of the impact caused by excessively high concentrations of gaseous molecular contaminants.

[0053] Please refer to Figure 2 , which illustrates a schematic diagram of a system for monitoring gaseous molecular contaminants according to some embodiments of the present disclosure. System 400a for monitoring gaseous molecular contaminants differs from system 400 primarily in that a heat shield 450 is added between the heating shock bottle 413 and the condensing shock bottle 402, and / or between the cooler 412 and the heater 418, to prevent the heating and cooling processes from interfering with each other. In system 400a for monitoring gaseous molecular contaminants, the distance between the heating shock bottle 413 and the condensing shock bottle 402, and / or the distance between the cooler 412 and the heater 418, is shorter than the corresponding distances in system 400. Heat shield 450 is used to prevent the heating and cooling processes from interfering with each other. The remaining configurations and arrangements of this system are the same as those of system 400 and are therefore not further described. In some embodiments, the material of heat shield 450 may include mica, silicon fiber, glass fiber, high-temperature resistant polymer material, or the like.

[0054] Please refer to Figure 3, which illustrates a schematic diagram of a system for monitoring gaseous molecular contaminants according to some embodiments of the present disclosure. System 400b for monitoring gaseous molecular contaminants differs from system 400 primarily in that it includes a thermal insulation box 452 to surround the heating shock bottle 413 and the heater 418, thereby preventing the heating and cooling processes from interfering with each other. In system 400b for monitoring gaseous molecular contaminants, the distance between the heating shock bottle 413 and the condensing shock bottle 402, and / or the distance between the cooler 412 and the heater 418, is shorter than the corresponding distances in system 400. Thermal insulation box 452 serves to prevent the mutual influence of heating and cooling, thereby shortening the distance between the cooling and heating sources. The remaining configurations and settings of this system are the same as those of system 400 and are therefore not further described. In some embodiments, thermal insulation box 452 may be made of mica, silicon fiber, glass fiber, high-temperature resistant polymer material, or the like.

[0055] Please refer to Figure 4 , which illustrates a schematic diagram of a system for monitoring gaseous molecular contaminants according to some embodiments of the present disclosure. System 400c for monitoring gaseous molecular contaminants differs from system 400 in that a thermal insulation box 452 is added to surround the heating shock bottle 413 and heater 418, and a thermal insulation box 454 is added to surround the condensing shock bottle 402 and cooler 412, thereby preventing the heating and cooling processes from interfering with each other. In system 400c for monitoring gaseous molecular contaminants, the distance between the heating shock bottle 413 and the condensing shock bottle 402, and / or the distance between the cooler 412 and the heater 418, is shorter than the corresponding distances in system 400. Thermal insulation boxes 452 and 454 are used together to prevent the mutual influence of heating and cooling, thereby shortening the distance between the cold and heat sources. The other configurations and settings of this system are the same as those of system 400 for monitoring gaseous molecular contaminants, and therefore will not be described in detail. In some embodiments, the material of the thermal insulation box 452 and the thermal insulation box 454 may include mica, silicon fiber, glass fiber, high temperature resistant polymer material or similar materials.

[0056] Please also refer to Figures 1 to 5 , Figure 5 FIG5 is a flow chart of a method for monitoring gaseous molecular contaminants according to some embodiments of the present disclosure. The method 500 includes the following operations to monitor gaseous molecular contaminants.

[0057] In operation 502, a sample liquid (e.g., deionized water) is added to the condensing impinger bottle 402 and the warming impinger bottle 413. In some embodiments, equal amounts of deionized water are added to the condensing impinger bottle 402 and the warming impinger bottle 413. In some embodiments, unequal amounts of deionized water are added to the condensing impinger bottle 402 and the warming impinger bottle 413. The amount of sample liquid in the warming impinger bottle 413 is proportional to the sampling time. Longer sampling times may require adding more sample liquid to the cold warming impinger bottle 413 to extend the end point at which the sample liquid evaporates.

[0058] In operation 504, a tube 406 is used to connect the condensation impinger bottle 402 and the heated impinger bottle 402 in series. The tube 406 is used to guide the gas to be monitored that is not dissolved in the sample liquid 414 of the heated impinger bottle 402 into the sample liquid 404 of the condensation impinger bottle 402. Therefore, one end 406a of the tube 406 is inserted into the heated impinger bottle 413 but not into the sample liquid 414 to receive the gas to be monitored in the heated impinger bottle 413. The other end 406b of the tube 406 is inserted into the sample liquid 404 of the condensation impinger bottle 402, thereby introducing the gas to be monitored into the sample liquid 404 and increasing its solubility.

[0059] In operation 506, a tube 416 is inserted into the sample liquid 414 in the heated impinger bottle 413. The tube 416 is used to introduce the external gas to be monitored into the sample liquid 414. Therefore, one end 416a of the tube 416 is positioned outside the heated impinger bottle 413 to receive the external gas to be monitored, while the other end 416b of the tube 416 is inserted below the liquid level of the sample liquid 414 to increase the solubility of the gas to be monitored. During the sampling process, the sample liquid 414 in the heated impinger bottle 413 gradually decreases in level due to evaporation. In some embodiments, to increase the solubility of the gas, the bottom end 416b of the tube 416 should be as close to or as close to the bottom surface of the heated impinger bottle 413 as possible, allowing the tube 416 to remain within the gradually decreasing sample liquid 414. During the sampling process, the sample liquid 404 in the condensation impinger bottle 402 gradually rises in level due to condensation of the evaporated sample liquid 414 from the heated impinger bottle 413. In some embodiments, the bottom end 406 b of the sampling tube 406 may be close to or abut against the bottom surface of the condensation impingement bottle 402 .

[0060] In operation 508, air pump 410, connected to condensation shock bottle 402 via tube 408, begins pumping air, providing a driving force for the flow of the monitored gas. Because tube 408 is inserted into condensation shock bottle 402 but not into sample liquid 404, the internal pressure of condensation shock bottle 402 decreases, allowing the monitored gas to flow from heated shock bottle 413 into condensation shock bottle 402. Simultaneously, the internal pressure of heated shock bottle 413 decreases, allowing tube 416 to continuously direct the external monitored gas into sample liquid 414 in heated shock bottle 413. Undissolved monitored gas is then directed by tube 406 into sample liquid 404 in condensation shock bottle 402.

[0061] In operation 510, the condensation shock vial 402 is cooled to a temperature below room temperature or near the freezing point of the sample liquid using the cooler 412, and the heated shock vial 413 is heated to a predetermined temperature above room temperature using the heater 418. In some embodiments, the cooler 412 is used to cool the condensation shock vial 402 to the freezing point of the sample liquid, and the heater 418 is used to heat the heated shock vial 413 to approximately 60°C to 65°C. In other embodiments, the condensation shock vial 402 is cooled to the freezing point of the sample liquid, and the heated shock vial 413 is heated to approximately 60°C to 65°C, so that the supersaturation ratio of the sample liquid in the condensation shock vial to the heated and humidified gaseous molecular contaminants reaches approximately 28 to 32. When the temperature heated by the heater 418 is below approximately 60°C, the effect of increasing the supersaturation ratio of the gaseous molecular contaminants is less significant. When the temperature heated by the heater 418 is above approximately 65°C, the time it takes for the sample liquid to evaporate completely is too short, which affects the sampling efficiency of the gaseous molecular contaminants. The temperature heated by heater 418 affects the time it takes for the sample liquid in heated shock bottle 413 to completely evaporate. The higher the heating temperature, the shorter the time it takes for the sample liquid to completely evaporate. When the sample liquid in heated shock bottle 413 completely evaporates, the effectiveness of heating and humidifying the monitored gas is reduced, and the efficiency of sampling gaseous molecular contaminants is also reduced. Therefore, the operator can adjust the cooling temperature of cooler 412 and the heating temperature of heater 418 based on the amount of sample liquid, the desired sampling time, and other conditions to achieve the desired monitoring time. At the end of sampling, the sample liquid in heated shock bottle 413 is completely evaporated and transferred to condensing shock bottle 402. Only the sample liquid 404 in condensing shock bottle 402 needs to be removed for measurement and analysis by the analyzer. In other operations, the distance between heated shock bottle 413 and condensing shock bottle 402 can be increased, or a heat shield 450 can be placed between heated shock bottle 413 and condensing shock bottle 402 to prevent the heating and cooling processes from interfering with each other. In other operations, a thermal insulation box ( 452 or 454 ) is provided to surround at least one of the heating shock bottle 413 and the condensing shock bottle 402 to prevent the heating and cooling processes from affecting each other.

[0062] After measuring and analyzing the concentration of gaseous molecular pollutants using the aforementioned method, these pollutants can be removed from the air using a chemical filter. A chemical filter contains a large amount of adsorbent. When air passes through the filter, gas molecules diffuse from the airstream onto the outer surface or pores of the adsorbent. These molecules then enter the pores and adsorb on the adsorbent surface. Gas molecules adsorbed on the surface diffuse to deeper, inner pore surfaces. Therefore, the adsorbent material facilitates adsorption or ion exchange reactions of gaseous molecular pollutants on the adsorbent surface. Chemical filters can contain a variety of filter media to target the five aforementioned categories of gaseous molecular pollutants: acids, bases, condensates, dopants, and metal contaminants. However, a single chemical filter typically cannot remove all gaseous molecular pollutants simultaneously. The filter media composition can be tailored to the type of gaseous molecular pollutants to be removed. The lifespan of a chemical filter depends on the average and peak concentrations of gaseous molecular pollutants in the environment, as well as the outlet concentration limit. The lifespan of a chemical filter may also depend on the filter's pressure drop, outgassing, efficiency, and filter media capacity. After measuring and analyzing the concentration of gaseous molecular pollutants in the above manner, it can be used to determine the frequency of replacement or regeneration of the chemical filter, and can also be used to adjust the composition of the filter material in the chemical filter.

[0063] After measuring and analyzing the concentration of gaseous molecular pollutants in the above manner, the plant-wide control limit can be reduced to local control (microenvironment system) to strictly control the cleanliness level inside the wafer box. The microenvironment system only locally increases the cleanliness around the wafer. The microenvironment system includes a storage container called a front-opening unified pod (FOUP) for transporting wafers and keeping them in a highly clean environment. The FOUP has an opening door at the front, through which the semiconductor wafer is inserted into or removed from the fixture. The FOUP includes a chamber consisting of a shell and a door, the shell is a holder for receiving semiconductor wafers, and the door is a component that opens or closes the shell. The FOUP keeps the semiconductor wafer in an airtight enclosed space to protect the semiconductor wafer from foreign matter or chemical contamination in the atmosphere. The FOUP is usually molded from plastic, and the airtightness between the shell and the door is maintained by a seal made of rubber or the like. The seal can cause leakage and the plastic and rubber can degas gaseous molecular contaminants. When wafers are transferred to or from a FOUP, outside air easily enters the FOUP. Consequently, the moisture and oxygen concentrations in the FOUP tend to increase over time. Furthermore, when semiconductor wafers with photoresist deposited thereon are stored in a FOUP, organic solvents evaporated from the photoresist and deposited on the inner wall of the shell. Consequently, even after the semiconductor wafers with photoresist deposited thereon are removed, the photoresist deposited on the inner wall of the shell evaporates again and contaminates the atmosphere in the FOUP. Moisture, oxygen, and contaminants in the FOUP can contaminate semiconductor wafers and cause yield loss. Using a vacuum pumping and nitrogen filling circulation mode to dilute the accumulated contamination concentration prevents dead corners in the airflow and purifies the gas at a faster rate, a common method for improving cleanliness in FOUPs.

[0064] After measuring and analyzing the concentration of gaseous molecular contaminants using the above method, normal background monitoring data can be established. When product yields are normal, fixed-point and regular testing of the process environment can be performed to establish a background value for gaseous molecular contaminants in the process environment. This value can be used as a reference in the event of future process problems or equipment replacements. Emergency sampling and monitoring can also be performed at appropriate times. When a process problem occurs or a suspected leak of inappropriate gaseous molecular contaminants is present, immediate sampling is required. The test data can be compared with the background value to facilitate appropriate resolution. Monitoring of changes in contaminant concentrations can be standardized, with regular quantitative testing of specific contaminants suspected of significantly impacting product yield to identify their impact and implement appropriate controls. When evaluating the efficiency of filtration equipment, the test values ​​for gaseous molecular contaminants can be used as a reference when selecting and replacing filter media for the process environment, avoiding wasteful replacements.

[0065] Common methods for dealing with gaseous molecular pollutants include removing the pollution source. If the gaseous molecular pollutants are caused by outdoor gases, finding the pollution source and removing it is the best way to improve the situation. However, the chemical raw materials used in general machines usually also cause pollution in the clean room environment. Therefore, the method of removing the pollution source is not suitable for the pollution source generated by the machine. Therefore, the treatment method for machines or other pollution sources where gaseous molecular pollutants cannot be removed is to isolate the pollution source. For example, the aforementioned FOUP is a way to isolate the pollution source. Eliminate or dilute by filtering to reduce environmental pollution. Common methods include installing the aforementioned chemical filter on the air conditioning box and machine in the area. However, the chemical filter can usually only filter a single chemical pollution source, and the filter has its life limit and needs to be measured and replaced regularly.

[0066] While not intended to be limiting, one or more embodiments of the present disclosure provide numerous benefits to integrated circuit lithography systems and related processes. For example, embodiments of the present disclosure provide methods and systems for monitoring gaseous molecular contaminants, providing improved sampling efficiency for gaseous molecular contaminants, thereby monitoring and improving the production environment of integrated circuit wafers, thereby increasing the yield and output of integrated circuit wafers.

[0067] According to some embodiments of the present disclosure, a method for monitoring gaseous molecular contaminants includes the following steps: A first sample liquid and a second sample liquid are added to a heated shock bottle and a condensing shock bottle, respectively, wherein a first tube extends from outside the heated shock bottle into the heated shock bottle and further into the first sample liquid, and a second tube is connected in series with the heated shock bottle and the condensing shock bottle. An air pump is connected to the condensing shock bottle to evacuate air, causing the first tube to draw a gas to be monitored and introduce it into the first sample liquid. The heated shock bottle is heated, causing the first sample liquid to evaporate and be collected by the condensing shock bottle through the second tube. In some embodiments, the heated shock bottle is heated to a temperature of approximately 60°C to approximately 65°C. In some embodiments, the method further includes cooling the condensing shock bottle. In some embodiments, heating the heated shock bottle and cooling the condensing shock bottle further comprises adjusting the supersaturation ratio of the sample liquid in the condensing shock bottle to the gaseous molecular contaminants to be between 28 and 32. In some embodiments, the method for monitoring gaseous molecular contaminants further includes inserting the second tube so that its bottom end approaches or abuts the bottom of the heated shock bottle. In some embodiments, an insulating plate is positioned between the condensing shock bottle and the warming shock bottle.

[0068] According to some embodiments of the present disclosure, a method for monitoring gaseous molecular contaminants includes the following steps: A first sample liquid and a second sample liquid are added to a first impinger bottle and a second impinger bottle, respectively, wherein a first tube extends from outside the first impinger bottle into the first impinger bottle and further extends into the first sample liquid, and a second tube is connected in series with the first impinger bottle and the second impinger bottle. The second impinger bottle is cooled. An air pump connected to the second impinger bottle is used to draw air, causing the first tube to draw a gas to be monitored and introduce it into the first sample liquid. In some embodiments, heating the impinger bottle and cooling the condensation impinger bottle further includes heating the impinger bottle to approximately 60°C to approximately 65°C and cooling the condensation impinger bottle to the freezing point of deionized water. In some embodiments, heating the impinger bottle and cooling the condensation impinger bottle further includes causing the supersaturation ratio of the sample liquid in the condensation impinger bottle to the gaseous molecular contaminant to range from approximately 28 to approximately 32. In some embodiments, the method for monitoring gaseous molecular contaminants further includes detecting the concentration of boron, phosphorus, or arsenic in the deionized water sampled in the condensation impinger bottle using an inductively coupled plasma mass spectrometer. In some embodiments, the method for monitoring gaseous molecular contaminants further includes detecting the second sample liquid using an inductively coupled plasma mass spectrometer.

[0069] According to some embodiments of the present disclosure, a system for monitoring gaseous molecular contaminants includes the following elements: a heating shock bottle for filling a first sample liquid; a condensing shock bottle for filling a second sample liquid; a heater for heating the heating shock bottle to a temperature above room temperature; a first tube connected between the heating shock bottle and the condensing shock bottle; a second tube inserted into the heating shock bottle; and an air pump connected to the condensing shock bottle. In some embodiments, the system for monitoring gaseous molecular contaminants further includes an insulation plate located between the condensing shock bottle and the heating shock bottle. In some embodiments, the system for monitoring gaseous molecular contaminants further includes an insulation box for surrounding the condensing shock bottle or the heating shock bottle. In some embodiments, the bottom end of the second tube is close to or abuts the bottom of the heating shock bottle. In some embodiments, the system for monitoring gaseous molecular contaminants further includes a cooler for cooling the condensing shock bottle to a temperature below room temperature.

[0070] The foregoing summarizes the features of several embodiments so that those skilled in the art may better understand the aspects of the present disclosure. Those skilled in the art will appreciate that they may readily use this disclosure as a basis for designing or modifying other processes and structures for achieving the same purposes and / or achieving the same advantages of the embodiments described herein. Those skilled in the art will also recognize that such equivalent constructions do not depart from the spirit and scope of the present disclosure, and that they may make various changes, substitutions, and modifications herein without departing from the spirit and scope of the present disclosure.

Claims

1. A method for monitoring gaseous molecular pollutants, characterized in that: include: A first sampling liquid and a second sampling liquid are added to a heating impingement bottle and a condensing impingement bottle, respectively. A first tube extends from outside the heating impingement bottle into the heating impingement bottle and further extends into the first sampling liquid. A second tube is connected in series with the heating impingement bottle and the condensing impingement bottle. Using an air pump connected to the condensation shock bottle to extract air, so as to reduce the internal air pressure of the condensation shock bottle and the heating shock bottle so that the first tube absorbs the gas to be monitored and introduces it into the first sampling liquid; heating the heating shock bottle so that the first sampling liquid evaporates and is collected by the condensing shock bottle through the second tube; and When the first sample liquid in the heated impingement bottle is completely evaporated, the second sample liquid in the condensed impingement bottle is taken out to be analyzed by an inductively coupled plasma mass spectrometer.

2. The method according to claim 1, characterized in that The temperature of the heated impact bottle is 60°C to 65°C.

3. The method according to claim 1, characterized in that Also includes: The condensation shock bottle was cooled.

4. The method according to claim 1, wherein Also includes: A heat insulation plate is arranged between the heating shock bottle and the condensing shock bottle.

5. A method for monitoring gaseous molecular pollutants, characterized in that: include: Adding a first sampling liquid and a second sampling liquid into a first impingement bottle and a second impingement bottle respectively, wherein a first tube extends from outside the first impingement bottle into the first impingement bottle and further extends into the first sampling liquid, and a second tube connects the first impingement bottle and the second impingement bottle in series; evaporating the first sampling liquid in the first impingement bottle; When the first sample liquid in the first impingement bottle has evaporated completely, taking out the second sample liquid in the second impingement bottle and detecting the second sample liquid by using an inductively coupled plasma mass spectrometer; cooling the second impingement bottle; and An air pump is connected to the second impact bottle to extract air, so as to reduce the internal air pressure of the first impact bottle and the second impact bottle so that the first tube absorbs a gas to be monitored and introduces it into the first sampling liquid.

6. The method according to claim 5, characterized in that The first shock bottle is a heated shock bottle.

7. The method according to claim 5, characterized in that The second shock bottle is a condensation shock bottle.

8. The method according to claim 5, characterized in that The first sampling liquid is deionized water.

9. The method according to claim 5, characterized in that The second sampling liquid is deionized water.

10. The method according to claim 5, characterized in that Also includes: The first impingement bottle was heated to 60°C to 65°C using a heater.

11. A system for monitoring gaseous molecular pollutants, characterized in that: include: a heated shock bottle, for filling a first sampling liquid; a condensation shock bottle, for filling a second sampling liquid; a heater for heating the heated shock bottle to a temperature above room temperature; a first tube connected between the heating shock bottle and the condensing shock bottle; a second tube, inserted into the heated shock bottle; an air pump connected to the condensing shock bottle and used to reduce the internal air pressure of the condensing shock bottle and the heating shock bottle; and An inductively coupled plasma mass spectrometer is used to analyze the second sample liquid in the condensed impingement bottle when the first sample liquid in the heated impingement bottle has been completely evaporated.

12. The system according to claim 11, wherein: Also includes: A heat insulation plate is located between the heating shock bottle and the condensing shock bottle.

13. The system according to claim 11, wherein: Also includes: A thermally insulated box surrounds the heated shock bottle.

14. The system according to claim 11, wherein: Also includes: A cooler is used to cool the condensation shock bottle to below room temperature.

15. The system according to claim 14, wherein: The cooler is used for cooling the condensation shock bottle to the freezing point temperature of the second sampling liquid.

16. The system according to claim 11, wherein: The heater is used to heat the heated impact bottle to 60° C. to 65° C.

17. The system according to claim 14, wherein: The cooler is used to cool the condensation shock bottle to the freezing point temperature of the second sampling liquid, and the heater is used to heat the heating shock bottle so that the supersaturation ratio of the second sampling liquid in the condensation shock bottle to the heated and humidified gaseous molecular pollutants reaches 28-32.

18. The system according to claim 11, wherein: The first sampling liquid is deionized water.

19. The system according to claim 11, wherein: The second sampling liquid is deionized water.

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