In situ clean apparatus and method thereof

An apparatus includes a sprinkler configured for spraying liquid and a member with a nano-coating surface. The nano-coating surface is configured to receive liquid sprayed from the sprinkler. The apparatus further includes a sensor associated with the member and the sensor is configured to detect a signal directly or indirectly corresponding to a film deposition on the nano-coating surface. Moreover, the apparatus has a controller coupled with the sensor and the sprinkler, wherein the signal detected by the sensor is transmitted to the controller and the controller is configured to command the sprinkler spraying liquid on the nano-coating surface while a value of the signal reaches a threshold value.

FIELD

The present disclosure relates to an in-situ clean apparatus and method thereof.

BACKGROUND

Chemical solutions and gases are used in different industries for manufacturing, however, the exhaust or byproducts produced during the process become a source of environment pollution. Authorities are tending to enforce stricter regulation to push manufacturers improving exhaust emission quality and waste management. A recent trends shows investment on abatement and exhaust system increases from manufacturing in order to meet green policy requirement while still sustain productivity

Film deposition or powder are often observed in abatement and exhaust system and mostly are formed because of unexpected reactions. The unexpected reactions usually originate from mixture of different exhaust gas or chemical in certain locations in the systems or an undesired condensation during transportation. To maintain exhaust system and abatement is a challenging topic to a production line because manufacturing equipments are always connected to exhaust system and it is necessary to be moved offline in order to conduct a regular inspection or an ex-situ clean process. Another issue is abrupt malfunction of exhaust system that occurs because an abnormal characteristic parameter or interruptions of power source, such as voltage sag. The abrupt malfunction stops manufacturing equipments and causes product scrap. Thus, in order to maintain a compatible productivity, a robust clean methodology or apparatus for an exhaust system and abatement is continuously to be sought.

DETAILED DESCRIPTION OF THE INVENTION

In the present disclosure, an in-situ cleaning apparatus is designed to be located in a system. In some embodiments, the system is an exhaust system. The exhaust system includes various sub systems such as conduit, scrubber, heater, fan, or other parts located in a path that exhaust gas passes. In some embodiments, the exhaust system is designed to be coupled to a semiconductor manufacturing equipments such as a wet etch bench, a deposition chamber, an etch chamber or a photo resist coater, etc. The in-situ cleaning apparatus is configured to automatically remove an undesired film deposition (or called build up) on a location inside the system. In some embodiments, some portions in the system are coated with nano scale particulates on top surface in order to effectively remove undesired film deposition from the portions.

In some embodiments, the in-situ cleaning apparatus is integrated in the system and designed to clean a predetermined location by a programmable controller. The cleaning operation is conducted without interrupting a normal operation of the system. In the present disclosure, “interrupting” or “intervention” of a system refers to an action or actions to shut down the system, in other words, to disable the system. The action or actions includes turning the electric power supplied to the system off, turning the system offline, discharging the system from a semiconductor manufacturing equipment, discharging a portion of the system from the system.

As used herein, “film deposition” refers to a layer or powders formed on a surface. In some embodiments, “film deposition” is interchangeable with “build up”. In some embodiments, film deposition is a clog that impedes gas flow in the system. In some embodiments, film deposition is a coating on a turbine blade of a fan. The coating increases load of the fan and alter balance on the turbine blade. Thus, an undesired vibration is observed. Film deposition is formed by various mechanisms in the system. In some embodiments, film deposition is formed by condensation of exhaust gas. In some embodiments, film deposition is formed by undesired reaction of exhaust gases. In some embodiments, film deposition is formed on a bending portion in a system that has turbulent flow.

As used herein, “nano coating” refers to a coating with a creating surface tension at the molecular level. Nano coating includes nano-sized powdered or particle feedstocks or combinations. In some embodiments, nano coating repels water (hydrophobic), while still allowing air to pass through a surface underneath. In some embodiments, nano coating has a thickness between about 40 nm to 250 nm. In some embodiments, nano coating is resistant to elevated temperatures, up to 500° C. In some embodiments, nano coating includes alumina, ceria, chromia, magnesia, silica, titania, yttria, zirconia. In addition to the single component particle feedstocks listed above, mixtures of particle or feedstocks can be employed. For example, mixtures of alumina and chromia, alumina and magnesia, alumina and silica, alumina and titania, chromia and silica and titania, titania and chromia and zirconia and yttria can also be utilized and may have numerous commercial applications. In some embodiments, the nano coating includes cross linking agents, such as HNO3, HCl, H2SO4.

As used herein, “control valve” is interchangeable with “switch”. In some embodiments, a control valve is connected to a hydraulic system and can be regulated by a controller.

FIG. 1is an apparatus installed to a wet etch equipment600in a semiconductor manufacturing line according to some embodiments of the present disclosure. The apparatus includes a sprinkler110. The sprinkler110has two nozzles110aand110bthat is respectively connected to a delivery pipe112. The delivery pipe112is further connected to a control valve500, which controls a hydraulic system used to supply liquid such as water to the nozzles110aand110b. Liquid supplied by the hydraulic system is pressurized in order to maintain a constant flow and speed when the sprinkler110is activated. In some embodiments, the pressure is designed in accordance with a hole size of the nozzle. In some embodiments, the hydraulic system supplies a pressure between about 20 psi and 40 psi. In some embodiments, the hydraulic system supplies a pressure at about 30 psi.

In some embodiments, nozzle is arranged based on where liquid is to be sprayed on. As inFIG. 1, a member200of the apparatus is an exhaust conduit that is connected to an exhaust outlet102of the wet etch equipment600. The other end of the exhaust conduit200is connected to drain, such as a pump, or a local exhaust system. The exhaust conduit200has several elbows, such as200a,200band200c. The elbows are vulnerable to have film deposition because exhaust gas flow stream is impeded therein. Nozzles are installed inside the conduit200and around the elbows. Like at elbow200a, a nozzle110ais installed in the conduit200around elbow200a. Further, the nozzle110ais configured to spray liquid on internal surfaces of the elbow200a. Similarly, a nozzle110bis installed around elbow200band the nozzle110bis configured to spray liquid on internal surfaces of the elbow200b. In some embodiments, nozzles are used to spray liquid drops having an average diameter between about 8.5 nm and about 11.2 nm. In some embodiments, nozzles are used to spray liquid drops having an average diameter between about 9 nm and about 10.5 nm. In some embodiments, nozzles are used to spray liquid drops having an average diameter at about 9.2 nm. Another adjustable factor to design the nozzle is distribution of the liquid drop size. In some embodiments, 99.9% of liquid drops sprayed from nozzles have a diameter smaller than about 54 nm. In some embodiments, 99.9% of liquid drops sprayed from nozzles have a diameter smaller than about 53.6 nm. In some embodiments, 99.9% of liquid drops sprayed from nozzles have a diameter smaller than about 60 nm.

In some embodiments, nozzle size is designed incorporative to the liquid pressure. For example, in an embodiment, the sprinkler is connected to a hydraulic system supplying liquid that is pressurized to be around 30 psi. An outlet of the nozzle is designed to be between 800 um and 1000 um. In some embodiments, an outlet of the nozzle is designed to be smaller than 900 um.

In the apparatus inFIG. 1, inner surfaces of elbows are covered with a nano coating202. Thus, film deposition or build forms on the top surface of the nano coating. In some embodiments, a portion of the nano coating is illustrated inFIG. 2. The nano coating has a substrate202awith several trenches202b. On the top surface, a chain of nano particulates are used to trap film deposition such as 30. In some embodiments, because the nano particulates are hydrophilic, when liquid such as water drop50is sprayed on the nano coating, the film deposition30is flushed away.

In some embodiments, the apparatus inFIG. 1has a sensor300coupled to a gauge305. The gauge305is disposed at a predetermined location inside the conduit200. In the present example, the gauge305is located close to the exhaust outlet102of wet etch equipment600. The gauge305is associated with the elbows of conduit200. In some embodiments, gauge305is configured to measure pressure inside conduit200and transmits a signal to the sensor300. In some embodiments, gauge305measures pressure around exhaust outlet102and converts to an electric signal and transmits the electrical signal to the sensor300. The pressure detected by sensor300corresponds to film deposition on nano coating, on where the nano coating202is disposed. In some embodiments, when film deposition on elbow200abecomes thicker, higher impedance is generated to block exhaust gas passing elbow200a, thus sensor300detects an increased pressure around exhaust outlet102. In some embodiments, sensor300is combined with gauge305as an integrated component and disposed inside the conduit200.

For an external sensor configuration (gauge inside the conduit and sensor disposed outside the conduit), there are various communication paths between sensor and gauge. In some embodiments, as inFIG. 1, gauge305communicates with sensor300through a wire302. In some embodiments, gauge305communicates with sensor300in a wireless manner.

Sensor300is coupled to a controller400and designed to transmit electrical signal to the controller400. In some embodiments, sensor300transmits electrical signal of the pressure measured by the gauge200to controller400. The controller400is connected with sensor300through a wire402. In some embodiments, controller400is coupled with sensor300through a wireless manner. In some embodiments, the controller400is a programmable logic controller (PLC). The PLC is programmed to process various types of signals. In some embodiments, the PLC includes a processor.

According to some embodiments of the present disclosure, the controller400is used to regulate the sprinkler110. As inFIG. 1, a controller400is coupled to a control valve500of the sprinkler110. The control valve500includes an electronic switch. The control valve500is used to regulate liquid supplied from the hydraulic system.

In some embodiments, a method of in-situ cleaning an internal member of an exhaust system is conducted by the apparatus inFIG. 1. Internal members such as elbows200aand200bare identified to be most vulnerable locations to have film deposition. The conduit200is disconnected from equipment600and applying a nano-coating on an internal surface of each elbow when equipment600is in idle. Gauge305is installed to monitor ambient condition near elbow200a. In some embodiments, the ambient condition near elbow200ais corresponding to a characteristic condition, such as film deposition around the elbow200a. In some embodiments, gauge305measures gas pressure in the conduit200and sends an electrical signal to the sensor300. The electrical signal is processed in sensor300and conveyed to the controller400in a same or different format by sensor300. After receiving the electrical signal from the sensor300, controller400compares a characteristic value of the electrical signal to a threshold value. If the characteristic value is greater than the threshold value, controller400sends a command to open control valve500. Liquid is introduced from the hydraulic system into the sprinkler110, thus nozzles110aand100bspray liquid on nano-coating surface202of elbows200aand200b.

In some embodiments, the threshold value is set at around 70 psi, which is about 1.3 times of gas pressure in conduit200during normal operation. When film deposition on nano-coating of elbows becomes thicker, gas pressure in conduit200is climbing up. Gauge305monitors gas pressure in conduit200and continuing transmitting signal to controller400via sensor300. As gas pressure in conduit200reaches 90 psi, controller400regulates the sprinkler110to spray water on elbows in order to remove film deposition on nano-coating of elbows. Once the clogged conduit is cleaned, gas pressure in conduit200is reduced to be less than about 90 psi. If gauge305still sends a gas pressure over 90 psi after clean, another in-situ clean is requested by the controller400. The cleaning operation is conducted without interrupting normal operation of equipment600. Thus, exhaust system is cleaned under in-situ mode.

FIG. 3is a scrubber100used as an exhaust system in a semiconductor manufacturing facility. In the present disclosure, “scrubber” refers to a diverse group of air pollution control devices that can be used to remove some particulates and/or gases from industrial exhaust streams. It includes dry scrubber, wet scrubber and hybrid mode scrubber. A “local scrubber” is referred to a scrubber near manufacturing tool. In some embodiments, a local scrubber is connected to an exhaust pump of semiconductor manufacturing equipment. A “central scrubber” is referred to a downstream scrubber that is used to collect exhaust from several local scrubbers. In the present disclosure, scrubber100is a local scrubber. Elements with same labeling numbers as those inFIG. 1are previously discussed with reference thereto and are not repeated here for simplicity.

The scrubber100is connected to a dry pump620. Dray pump620is connected to an exhaust conduit605of semiconductor manufacturing equipment (not shown). In some embodiments, the semiconductor manufacturing equipment uses gases including chlorine based or fluorine based chemicals. One end of pump620is connected to a feeding pipe525, which guides exhaust gas into the scrubber100. The scrubber100has a conduit200connected with a feeding pipe525. The inner surface of the conduit200is covered with a nano-coating202through the whole conduit200. On the other end of the conduit200, a chamber450is connected. The chamber450has a heater453used to burn unreacted gas in order to reduce pollution. The chamber450is connected to another conduit200aat the other end. A portion of the inner surface of the conduit200ais coated with a nano-coating202.

A pressure gauge305is located at a predetermined position in conduit200. In some embodiments, there are several gauges disposed on different locations according to the requirement. For example, a gauge is disposed in conduit200a. The gauge(s) measure the gas pressure inside conduits and feedback to a sensor300. As in the aforementioned embodiments, the signal is transmitted from the gauges to sensor in a wire or wireless manner. In some embodiments, gauges are arranged to be near to nozzles110a-110d. As inFIG. 3, nozzles are arranged in conduit200or200aand designed to be able to spray liquid on the nano-coating202. In some embodiments, nozzles are arranged at locations where more film deposition is observed. In some embodiments, nozzles are arranged to be near to elbows since most turbulent flow occurs therein. An unexpected reaction of exhaust gas accelerates build up of film depostion. In some embodiments, nozzles are arranged to be near to a cool part of conduits since condensation of exhaust gas transforms into film depostion.

As the film deposition building up in the conduits, pressure in the conduits climbs up. The elevated pressure signal is sent to the sensor300from the gauge305. Once the controller400reads a value sent from the sensor300and determines that the value is greater than a threshold value, the controller400regulates a switch500to turn on the nozzle and spray liquid on nano-coating surface. In some embodiments, there are more than one zone and each zone such as conduit200and conduit200arespectively has an independent gauge installed. The sensor300collects signals from different zones and transmits the signals to the controller400. The controller400processes the signals and determines that which zone's pressure is greater than the threshold value. Then the controller400regulates the switch corresponding to that specific zone. For example, when a gauge in conduit200asends a pressure signal greater than the threshold value and a gauge305in conduit200sends a pressure signal less than the threshold value, controller400only turns switch500aon.

FIG. 4is an exhaust system located in a manufacturing site. The exhaust system has a turbine420driven by a motor413. The turbine420includes several blades420-1.FIG. 4is a side view of the turbine hence only a housing420-2of the turbine420is observed. Turbine blades420-1are enclosed in the housing420-2thus are depicted with dotted lines. The turbine420is used to draw air from an exhaust inlet and push air out to an exhaust outlet. Because the air contacts the top surface of each blade directly, film deposition is easily observed. The top surface of each blade is covered by nano-coating202such that any film deposition is attached on the nano-coating202. A sensor300is installed on a shaft417of the turbine420. In some embodiments, sensor300is a vibration sensor. The sensor300is used to detect a characteristic condition such as vibration of the shaft417and blades420-1, wherein the vibration is associated with balance and load of the turbine blades420-1.

As film deposition starts building on the blades420-1, balance and load are changed. The sensor300periodically measures vibration of the shaft417and transmits an electrical signal associated with the measured vibration to a controller400. In some embodiments, the electrical signal is transmitted to the controller400in a wireless manner. The controller400compares the electrical signal to determine if vibration of the turbine blades420-1is greater than a threshold value. When vibration of the turbine blades420-1is smaller than the threshold value, the valve or switch500is closed. When vibration of the turbine blades420-1is greater than the threshold value, the controller400sends a command to open the valve or switch500. Liquid from a hydraulic system is introduced into a sprinkler110and nozzle110ato spray liquid on the nano-coating turbine blades420-1. An in-situ clean is conducted by removing film deposition from blades420-1. Turbine420is continuous in normal operation without any intervention during the in-situ clean operation. Sensor300constantly sends vibration signal to the controller400. Once the controller400discovers that the characteristic condition, vibration, of blades420-1are reduced under the threshold value, the switch500is closed by a command from the controller400.

Some nozzles such as110band110care installed near a damper425of the system. The damper425is used to adjust the outlet flow and is another member that is vulnerable to film deposition. In some embodiments as inFIG. 4, nozzles110band110cshare a same switch500with nozzle110a. The damper425is in-situ cleaned simultaneously with the blades420-1. In some embodiments, nozzles110band110care connected to a separate switch that is coupled with the controller400. The controller400controls multiple switches and regulate sprinkler in different zone independently.

In some embodiments, a controller is combined with a sensor to become an integral part. Housing is used to accommodate the controller and the sensor together. The integral part has a wireless connection port in order to operation in a remote mode.

FIG. 5is a flow diagram of an in-situ method500used to clean an exhaust system without interrupting a normal operation of the exhaust system. The method500includes an operation502. In operation502, a nano-coating is formed on a surface of a member in the exhaust system. In some embodiments, the member to be coated is a part or component most vulnerable to film deposition. During a regular maintenance or system fault recovery, the surface condition of the member can be observed to determine if the member is under a sever environment to have film deposited. In operation504, a characteristic condition around the member is detected. In some embodiments, the characteristic condition includes gas pressure, vibration. The characteristic condition is detected or measured by a sensor. In some embodiments, the sensor detects the characteristic condition indirectly through a gauge. In some embodiments, the sensor detects the characteristic condition in a wireless manner.

In operation506, the characteristic condition in transmitted to a controller from the sensor. The transmission is by a wire or wireless manner. In operation508, a sprinkler is regulated by the controller in accordance with the characteristic condition. In operation510, liquid is sprayed on the nano-coating. In some embodiments, the sprinkler is turned on by the controller. In some embodiments, the controller compares the characteristic condition with a threshold value. If the characteristic condition is greater than the threshold, the controller commands to turn on the sprinkler.

An apparatus includes a sprinkler configured for spraying liquid and a member with a nano-coating surface. The nano-coating surface is configured to receive liquid sprayed from the sprinkler. The apparatus further includes a sensor associated with the member and the sensor is configured to detect a signal directly or indirectly corresponding to a film deposition on the nano-coating surface. Moreover, the apparatus has a controller coupled with the sensor and the sprinkler, wherein the signal detected by the sensor is transmitted to the controller and the controller is configured to command the sprinkler spraying liquid on the nano-coating surface while a value of the signal reaches a threshold value.

An apparatus is configured to be installed in an exhaust system and the apparatus includes a member. The member is an exhaust pipe with a nano-coating surface. The nano coating surface is an inner surface of the exhaust pipe.

An apparatus is configured to be installed in an exhaust system and the apparatus includes a member. The member is a local scrubber, a central scrubber, a conduit connected to semiconductor wafer manufacturing equipment, a turbine blade in an exhaust system, a damper, a bevel, an exhaust pipe, a inner surface of a dry pump.

A system includes an in-situ cleaning apparatus located in the system. The in-situ cleaning apparatus is configured to automatically remove an undesired film deposition on a location inside the system without intervention. The in-situ cleaning apparatus includes a nano-coating film on the location and a nozzle configured to spray liquid on the nano-coating film. The in-situ cleaning apparatus includes a sensor configured for monitoring a characteristic condition around the location and a controller configured to receive a signal from the sensor and process the signal to generate a result. In some embodiments, the controller is configured to regulate the nozzle in accordance with the result generated by the controller.

A system includes an in-situ cleaning apparatus located in the system. The in-situ cleaning apparatus is configured to automatically remove an undesired film deposition on a location inside the system without intervention. The location is near an exhaust outlet of semiconductor equipment, wherein the exhaust outlet is configured to receive exhaust gas from the semiconductor equipment.

A system includes an in-situ cleaning apparatus located in the system. The in-situ cleaning apparatus is configured to automatically remove an undesired film deposition on a location inside the system without intervention. The in-situ cleaning apparatus includes a nano-coating film on the location and a nozzle configured to spray liquid on the nano-coating film. The nozzle is connected to a hydraulic system.

A system includes an in-situ cleaning apparatus located in the system. The in-situ cleaning apparatus is configured to automatically remove an undesired film deposition on a location inside the system without intervention. The in-situ cleaning apparatus includes a nano-coating film on the location and a nozzle configured to spray liquid on the nano-coating film. The nozzle is connected to a hydraulic system and designed to spray liquid drops, and an average diameter of the liquid drops is between about 8.5 nm and about 11.2 nm.

A system includes an in-situ cleaning apparatus located in the system. The in-situ cleaning apparatus is configured to automatically remove an undesired film deposition on a location inside the system without intervention. The in-situ cleaning apparatus includes a nano-coating film on the location and a nozzle configured to spray liquid on the nano-coating film. The nozzle is connected to a hydraulic system and designed to spray liquid drops having a size distribution of 99.9% of the liquid drops is to have a diameter smaller than about 54 nm.

A system includes an in-situ cleaning apparatus located in the system. The in-situ cleaning apparatus is configured to automatically remove an undesired film deposition on a location inside the system without intervention. The in-situ cleaning apparatus includes a nano-coating film. The nano-coating film includes silicon oxide

An in-situ cleaning method includes forming a nano-coating on a surface of a member in an exhaust system and detecting a characteristic condition near the member. The in-situ cleaning method includes transmitting the characteristic condition to a controller and regulating a sprinkler by the controller in accordance with the characteristic condition. The in-situ cleaning method includes spraying liquid on the nano-coating.

An in-situ cleaning method includes comparing the characteristic condition with a threshold value.

Although the present invention and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations cancan be made herein without departing from the spirit and scope of the invention as defined by the appended claims. For example, many of the processes discussed above can be implemented in different methodologies and replaced by other processes, or a combination thereof.