APPARATUS WITH HEATED FILTER AND OPERATION METHOD OF THE SAME

An apparatus includes a process chamber, a vacuum pump disposed downstream of the process chamber for discharging a fluid flow from the process chamber, a filter mounted between the process chamber and the vacuum pump for filtering the fluid flow, and a heating device disposed to heat the filter.

BACKGROUND

In the manufacturing process of semiconductor devices, various apparatuses are utilized, such as lithographic apparatus, etcher, furnace, implantation apparatus, deposition apparatus, measuring apparatus, etc. During mass production of the semiconductor devices, each apparatus is regularly subjected to preventive maintenance so as to provide a chamber environment with less defect sources. With the continuous miniaturization of the semiconductor devices, the chamber environment in each apparatus is being continuously improved so as to achieve a relatively higher rate of product yield and/or a lower cost for manufacturing the semiconductor devices.

DETAILED DESCRIPTION

For the purposes of this specification and appended claims, unless otherwise indicated, all numbers expressing amounts, sizes, dimensions, proportions, shapes, formulations, parameters, percentages, quantities, characteristics, or other numerical values used in the specification and claims, are to be understood as being modified in all instances by the term “about” even if the term “about” is not explicitly recited with the values, amounts or ranges. Accordingly, unless indicated to the contrary, the numerical parameters set forth in the following specification and appended claims are not and need not be exact, but may be approximations and/or larger or smaller than specified as desired, may encompass tolerances, conversion factors, rounding off, measurement error, and other factors known to those of skill in the art depending on the desired properties sought to be obtained by the presently disclosed subject matter. For example, the term “about,” when used with a value, can capture variations of, in some aspects±10%, in some aspects±5%, in some aspects±2.5%, in some aspects±1%, in some aspects±0.5%, and in some aspects±0.1% from the specified amount, as such variations are appropriate to perform the disclosed methods or employ the disclosed compositions.

In an apparatus for treating a substrate, a gas evacuation system is often configured downstream of a process chamber to discharge gaseous substances when the substrate is treated in the process chamber. The gaseous substances in the process chamber may include a resultant gas and/or an excess portion of precursor gases, and may have a relatively high temperature. Typically, a filter is used to prevent entrance of particles (which may undesirably generated during treatment of the substrate) entrained in the gaseous substances into the gas evacuation system. Since the gas evacuation system is usually placed at an ambient temperature, the gaseous substances, which have a relatively high temperature, are gradually cooled down and transformed into solid substances (which may contaminate the substrate when distributed in the process chamber) in the pathway toward the gas evacuation system. As such, the gas evacuation system provides a driving force to move the solid substances away from the substrate in the process chamber (for reducing possible defects on the substrate), and the filter (for preventing damages to the gas evacuation system) is provided to collect the solid substances thereon. Replacement of the filter regularly is required in order to effectively remove the solid substances and/or the particles. The frequency for replacement of the filter will affect the cost for treating the substrate.

Therefore, the present disclosure is directed to an apparatus for treating a substrate. The substrate treated with the apparatus can have fewer defects.FIG.1is a schematic view illustrating an apparatus1in accordance with some embodiments. In some embodiments, the apparatus1is used for dry etching the substrate (W). In some embodiments, the apparatus1may be a may be a plasma etching device, such as reactive-ion etcher, inductively-coupled plasma reactive-ion etcher, or capacitively-coupled plasma reactive-ion etcher, a plasma deposition device, but is not limited thereto.

The apparatus1includes a housing2, a substrate retainer3, a plasma generator4, a vacuum pump5, a filter6, and a heating device7.

The housing2includes a process chamber21for treating the substrate (W) using a plasma (P). In some embodiments, the substrate (W) may include a base substrate (not shown) and/or one or more materials (not shown) formed on the base substrate. The base substrate be made of elemental semiconductor materials, such as crystalline silicon, diamond, or germanium; compound semiconductor materials, such as silicon carbide, gallium arsenide, indium arsenide, or indium phosphide; or alloy semiconductor materials, such as silicon germanium, silicon germanium carbide, gallium arsenide phosphide, or gallium indium phosphide. In addition, the base substrate may be a bulk silicon substrate, a silicon-on-insulator (SOI) substrate, or a germanium-on-insulator (GOI) substrate. In some embodiments, the material(s) on the base substrate may constitute an epitaxial layer and/or a patterned structure thereon for forming electronic devices (not shown) subsequently. The material(s) to be treated by the plasma may be a semiconductor material, a dielectric material, an electrically conducting material, other suitable materials, or combinations thereof. In some embodiments, the plasma is used for selectively etching selected one(s) of the materials of the substrate (W).

The substrate retainer3is disposed in the housing2and is configured to retain the substrate (W) in the process chamber21, so that the substrate (W) can be treated by the plasma (P). In some embodiments, the substrate retainer3includes an electrostatic chuck (not shown), but not limited thereto. Other substrate retainers suitable for support or fixation of the substrate (W) are within the contemplated scope of the present disclosure.

The plasma generator4is used for generating the plasma (P). In some embodiments, the plasma generator4includes a dielectric plate41, a first gas inlet42and a plasma coil43. The dielectric plate41is disposed above the substrate retainer3. The first gas inlet42is formed in the dielectric plate41and configured to introduce a first precursor gas into the process chamber21. In some embodiments, the plasma coil43is a transformer-coupled plasma coil. The plasma coil43is disposed above the dielectric plate41to ionize the first precursor gas in the process chamber21so as to generate the plasma (P) in the process chamber21when a power is applied to the plasma coil43. In some embodiments, the first precursor gas may include a halogen-containing gas, an inert gas (or a carrier gas), or a combination thereof. The halogen-containing gas is provided to react with the material(s) of the substrate (W) so as to form volatile reactants. In some embodiments, the halogen-containing gas may include hydrogen fluoride (HF), nitrogen fluoride (NFx), carbon fluoride (CFx), sulfur fluoride (SFx), other suitable gases, or combinations thereof. The inert gas is provided to adjust the concentration of the halogen-containing gas in the process chamber21. In some embodiments, the inert gas may include helium, argon, and a combination thereof. In some embodiments, helium and/or argon may be also used to bombard the surface of the substrate (W) in the case that a power is applied to the substrate retainer3. In order to increase an etching selectivity of a material relative to other materials, the first precursor gas may further include a carbon-containing gas. The carbon-containing gas is provided to adjust a ratio of fluorine to carbon in the plasma (P), thereby increasing the etching selectivity. That is, a surface portion of the substrate (W) may have an etching rate higher than that of another surface portion of the substrate (W). The surface portions may be made of different materials, or the surface portions may include the same material species but have different atomic compositions. In some embodiments, the carbon-containing gas may include non-substituted hydrocarbon gas (e.g., methane (CH4)), a halogen substituted hydrocarbon gas (e.g., fluoromethane (CH3F), trifluoromethane (CHF3)), other suitable carbon-containing gases, or combinations thereof. In view of the presence of the carbon-containing gas, polymer-like byproducts (such as hydrocarbon monomers, hydrocarbon polymers, halocarbon monomers, halocarbon polymers (e.g., fluorocarbon polymers), other suitable monomers and/or polymers, or combinations thereof) may be formed during the etching process. Since the process chamber21is kept at a plasma treating temperature (which is a relatively higher temperature), such byproducts may be kept in a gaseous form at least on the substrate (W). In some cases, when parts of an inner surface of the housing21have a temperature lower than that of the substrate (W), such byproducts may be transformed into a solid form and then observed on the inner surface of the housing21. In some embodiments, a plurality of heating elements31may be disposed inside the substrate retainer3and/or inside the process chamber21. In some embodiments, a heating coil24may be provided to heat the process chamber21. In some embodiments, the heating coil24is disposed to surround a part of the housing2for heating the process chamber21. As such, a temperature of the substrate (W) can be kept at or very close to the plasma treating temperature. In some embodiments, the plasma generator4further includes a plurality of second gas inlets23formed in the housing2. The second gas inlets23are angularly spaced apart from each other so as to introduce a second precursor gas into the process chamber21through the second gas inlets23. Therefore, the second precursor gas is permitted to be ionized, together with the first precursor gas, to generate the plasma (P). Possible gases for the second precursor gas are similar to the first precursor gas, and details thereof are omitted for the sake of brevity. In some embodiments, at least one of the first and second precursor gases includes the hydrocarbon gas. In some embodiments, both the first and second precursor gases include the hydrocarbon gas. In some embodiments, the first and second precursor gases may be the same or different from each other.

The vacuum pump5is disposed downstream of the process chamber21for discharging a fluid flow (F) from the process chamber21. In some embodiments, the fluid flow (F) may contain products resulted from the plasma etching, the byproducts, non-reacted first and second precursor gases, and the inert gas. By the driving force provided by the vacuum pump5, the solid byproducts on the inner surface of the housing2may also be entrained in the fluid flow (F), and thus the byproducts in the fluid flow (F) may be in both the gaseous form and the solid form. The filter6is mounted between the process chamber21and the vacuum pump5for filtering the fluid flow (F). In some embodiments, in addition to the particles (undesirably generated during treatment of the substrate (W)), the solid byproducts may be also filtered out by the filler6so as to prevent the vacuum pump5from being adversely affected by solids engrained in the fluid flow (F). In some embodiments, the filter6is a mesh filter. The heating device7is disposed to heat the mesh filter6so as to increase a gas percentage in the fluid flow (F) when the fluid flow (F) passes through the mesh filter6. In the case that the mesh filter6is not heated, since the mesh filter6is located downstream of the process chamber21and has a temperature much lower than the plasma treating temperature, the byproducts in the fluid flow (F) have a relatively higher percentage of the solid byproducts, and thus a service life of the mesh filter6may be relatively short. By heating the mesh filter6to above a predetermined temperature which is closer to the plasma treating temperature, the gas percentage in the fluid flow (F), when the fluid flow (F) passes through the mesh filter6, can be greatly increased, and the service life of the mesh filter6can thus prolonged, thereby reducing the cost for treating the substrate (W).

In some embodiments, the apparatus1further includes a throttle valve8coupled to an outlet of the housing2and disposed downstream of the process chamber21for regulating a flow rate of the fluid flow (F) entering the vacuum pump5.

FIG.2is an enlarged, fragmentary sectional view of the vacuum pump5, the mesh filter6, the heating device7, and the throttle valve8in accordance with some embodiments.FIG.3is an exploded perspective view illustrating the mesh filter6and the heating device7in accordance with some embodiments. As shown inFIG.2, an end face of an outlet tube81of the throttle valve8is in abutting engagement with an end face of an inlet tube51of the vacuum pump5, and thus an outlet of the throttle valve8(surrounded by the outlet tube81) is fluidly connected to an inlet of the vacuum pump5(surrounded by the inlet tube51). An inner surface of the inlet tube51has a first portion52, a second portion54, and a shoulder portion53. The second portion54is located upstream of the first portion52. The inlet tube51has a first inner dimension (X1) at the first portion52and a second inner dimension (X2) at the second portion54. The second inner dimension (X2) is larger than the first inner dimension (X1). The shoulder portion53interconnects the first and second portions52,54and is configured to permit the mesh filter6to be disposed thereon. In some embodiments, the mesh filter6may have a circular shape (seeFIG.3) and have a diameter ranging from about 25 cm to about 45 cm. Thus, the shoulder portion53may be in an annular shape to support a peripheral region of the circular mesh filter6. In some embodiments, the mesh filter6may be made of aluminum-magnesium alloy, but not limited thereto. Other suitable materials for the mesh filter6are within the contemplated scope of the present disclosure. In some embodiments, the vacuum pump5includes a turbo molecular pump, but not limited thereto. Other vacuum pumps5suitable for discharging the fluid flow are within the contemplated scope of the present disclosure.

As shown inFIGS.2and3, the heating device7includes a conduction unit70, a heat generator73, and one or more temperature sensors74.

The temperature sensor(s)74are provided for detecting a temperature of the mesh filter6. In some embodiments, as shown inFIG.2, the temperature sensor(s)74may be disposed (i) on an inner surface of the outlet tube81or on the second portion54proximate to the mesh filter6, (ii) in contact with the mesh filter6, and/or (iii) on the first portion52proximate to the mesh filter6.

The heat generator73is configured to directly or indirectly convert electrical energy to heat energy, and is in signal communication with the temperature sensor(s)74in a wired or wireless manner. The conduction unit70is provided to transmit the heat energy from the heat generator73to the mesh filter6. In some embodiments, the heat generator73includes an electrical resistor731and a controller732. The electrical resistor731is switchable between an on-state and an off-state by the controller732, and is in thermal contact with the conduction unit70for transmitting heat energy generated from the electrical resistor731to the conduction unit70. The controller732is in signal communication with the temperature sensor(s)74and the electrical resistor731in a wired or wireless manner. When the heat generator73is actuated, the controller732functions by switching the electrical resistor731between the on-state and off-state based on signal(s) from the temperature sensor(s)74. When the electrical resistor731is switched to the on-state, electrical energy (i.e., current) is applied to the electrical resistor731to convert the electrical energy into the heat energy. When the electrical resistor731is switched to the off-state, the electrical energy is not applied to the electrical resistor731. When the signal(s) from the temperature sensor(s)74reveal that the temperature of the mesh filter6is higher than the predetermined temperature, the controller732will switch the electrical resistor731to the off-state; and when the signal(s) from the temperature sensor(s)74reveal that the temperature of the mesh filter6is lower than the predetermined temperature, the controller732will switch the electrical resistor731to the on-state. As such, the mesh filter6can be kept at a temperature that is at least above the predetermined temperature. Other configurations suitable for the heat generator73are within the contemplated scope of the present disclosure.

In some embodiments, the heat generator73is disposed outside a pathway of the fluid flow (F) (e.g., outside of the vacuum pump5), and the conduction unit70includes a conduction base71and a conduction rod72. The conduction base71is configured to support the mesh filter6on the shoulder portion53. The conduction rod72extends through the inlet tube51so as to bring the conduction base71into thermal contact with the electrical resistor731of the heat generator73, thereby transmitting the heat energy from the heat generator73to the mesh filter6through the conduction unit70. In some embodiments, as shown inFIG.3, the conduction unit70may include two or more of the conduction rods72for transmitting the heat energy to different parts of the conduction base71. In some other embodiments, the conduction unit70may include a single conduction rod72, as shown inFIG.6. The conduction base71and the conduction rod(s)72may include a high thermal conductivity material. Possible materials for each of the conduction base71and the conduction rod(s)72may include an elemental metal (for example, but not limited to, copper, aluminum, or silver), an alloy (for example, but not limited to, the alloy including copper, aluminum, silver, or combinations thereof), a ceramic material (for example, but not limited to, boron nitride, aluminum nitride, aluminum nitride, silicon carbide, or combinations thereof), a carbon material (for example, but not limited to, nature or synthetic diamond, graphene, graphite, or carbon fiber), a thermal conductivity polymer (for example, but not limited to, polyethylene or polypropylene), or combinations thereof. Other high thermal conductivity materials suitable for the conduction base71and the conduction rod(s)72are within the contemplated scope of the present disclosure. In some embodiments, the material of each of the conduction base71and the conduction rod(s)72may a thermal conductivity greater than about 20 Wm−1K−1, about 200 Wm−1K−1, about 300 Wm−1K−1, about 400 Wm−1K−1, about 1000 Wm−1K−1or about 2000 Wm−1K−1. In some embodiments, the material of each of the conduction base71and the conduction rod(s)72has an electric resistance ranging from about 10−8Ωm to about 10−7Ωm, from about 10−7Ωm to about 10−6Ωm, from about 10−6Ωm to about 10−5Ωm, or from about 10−5Ωm to about 10−4Ωm. The conduction base71may be made of a material the same as or different from that of the conduction rod(s)72.

The conduction base71is in direct contact with the mesh filter6. In some embodiments, the conduction base71is disposed downstream of the mesh filter6. In some embodiments, the conduction base71is mounted beneath and extends along a periphery of the mesh filter6to form an opening711for passage of the fluid flow (F). Thus, the mesh filter6can be uniformly heated through the conduction base71. In some embodiments, the conduction unit71is disposed on the shoulder portion53and sandwiched between the shoulder portion53and the mesh filter6. In some embodiments, the conduction base71is in a form of a ring. In some embodiments, an inner dimension of the conduction base71is smaller than an outer dimension of the mesh filter6, and an outer dimension of the conduction base71is larger than the first inner dimension (X1), so that the mesh filter6can be disposed on the conduction base71. In some embodiment, at least one of the conduction base71and the mesh filter6is in fitting engagement with the second portion54of the inner surface of the inlet tube51. In some embodiments, the outer dimension of the conduction base71is substantially the same as that of the mesh filter6. In some embodiments, a distance D1between an outer periphery and an inner periphery of the conduction base71ranges from about 0.5 cm to about 3.0 cm.FIGS.4and5are views respectively similar toFIGS.2and3, but illustrating another positional relationship between the conduction base71and the mesh filter6in accordance with some modified embodiments. In this case, the mesh filter6is fittingly engaged in the opening711of the conduction base71. Other configurations suitable for the conduction unit70are within the contemplated scope of the present disclosure.

In some embodiments, the housing2further includes a communication chamber22disposed downstream of the process chamber21and upstream of the mesh filter6. In some embodiments, the apparatus1further includes a supporting frame9which is configured to support the substrate retainer3, and which is disposed inside the housing2to partition an inner space of the housing2into the process chamber21and the communication chamber22. The supporting frame9is formed with a plurality of venting bores91for passage of the fluid flow (F). Since the heating elements31and the heating coil24are disposed in positions spaced apart from the communication chamber22, the solid byproducts may be also observed in the communication chamber22.

In some alternative embodiments, the apparatus1may further include additional features, and/or some features present in the apparatus1may be modified, replaced, or eliminated without departure from the spirit and scope of the present disclosure. For example, in some embodiments not shown herein, the apparatus after appropriate modification may be used for depositing films on the substrate. For example, the apparatus after appropriate modification may be used for a plasma enhanced chemical vapor deposition. Likewise, the mesh filter6may be applied to other apparatus including a vacuum pump.

FIG.7is a flow diagram illustrating a method10in accordance with some embodiments.FIG.8is a schematic view similar toFIG.1but illustrating a stage of the apparatus, where the plasma generator4is not actuated, in accordance with some embodiments. Similar numerals from the above-mentioned embodiments are used where appropriate. In some embodiments, the method10includes steps S11to S13.

Referring toFIGS.7and8, the method10begins at step S11, where, prior to actuating the plasma generator4, the heating device7is actuated to heat the mesh filter6from the ambient temperature to the predetermined temperature. Determination of the predetermined temperature will be described later in the disclosure. The temperature detected by the temperature sensor(s)74(see alsoFIG.2) may be the same as the ambient temperature before actuating the heating device7, and may be similar, close, or greater than the predetermined temperature after step S11.

In some embodiments, the method10may further include a step of placing the substrate (W) on the substrate retainer3and a step of elevating a temperature of the process chamber21to the plasma treating temperature (using the heating elements31and/or the heating coil24). In some embodiments, placing the substrate (W) may be performed before or after actuating the heating device7for heating the mesh filter6. In some embodiments, the above two steps and step S11may be performed at the same time. Once the temperature detected by the temperature sensor(s)74reaches the predetermined temperature, and the substrate (W) and the process chamber21are heated to the plasma treating temperature, the method10may proceed to the next step.

Referring toFIGS.7and1, the method10proceeds to step S12, where the plasma generator4is actuated to permit the substrate (W) to be treated by the plasma (P) in the plasma chamber21at the plasma treating temperature.

In some embodiments, selected one(s) of the materials of the substrate (W) may be etched using the plasma (P). The plasma treating temperature may range from about 70° C. to about 400° C.

In step S12, the first and second precursor gases for generating the plasma (P) are respectively introduced through the first and second gas inlets42,23into the process chamber21, and are ionized to generate the plasma (P) by the plasma generator4when a power is applied to the plasma coil43. The first and second precursor gases are described above and thus are not described for sake of brevity.

Since the temperature (i.e., the plasma treating temperature) inside the process chamber21is relatively high, the polymer-like byproducts, generated in the plasma treatment, may be present as the gaseous form.

Referring toFIG.7, the method10proceeds to step S13, where the vacuum pump5is actuated to direct the fluid flow (W) to sequentially pass through the communication chamber22and the mesh filter6. In some embodiments, the vacuum pump5is actuated in step13for directing the fluid flow (W) to flow away from the process chamber21after step12is finished, as illustrated inFIG.7. In some other embodiments, the vacuum pump5may be actuated before step S12, and thus, once the plasma is generated to treat the substrate (W), the fluid flow (F) including the products resulting from the plasma etching, the byproducts, non-reacted first precursor gas, the carrier gas can be readily and continuously drawn out of the housing2through the driving force from the vacuum pump5.

Since the communication chamber22is used for communicating the process chamber21with the vacuum pump5, the fluid flow (F) leaving the processing chamber21and heading into the communication chamber22may have a relatively lower temperature (i.e., a cooled down temperature that is lower than the plasma treating temperature). As such, the gaseous byproducts contained in the fluid flow (F) may be transformed into the solid byproducts which may entrained in the fluid flow (F) or deposited on the inner surface of the housing2at the communication chamber22. The solid byproducts on the inner surface of the housing2may be detached from the housing2and also be entrained in the fluid flow (F) for a period of time.

When the fluid flow (F) reaches and is heated by the mesh filter6, solid portions (including the polymer-like byproducts and the particles undesirably generated in step12) in the fluid flow (F), especially the polymer-like byproducts, are likely to transform back to the gaseous form. As such, gas portions (including the gaseous byproducts transformed from the solid byproducts) pass through the mesh filter6, and the solid byproducts (which are not transformed back to the gaseous form) and the particles are collected on the mesh filter6. Evidently, the predetermined temperature can be determined by a transformation temperature of the solid byproducts from the gaseous byproducts (i.e., the deposition temperature of the gaseous byproducts). Therefore, the amount of solid byproducts collected by the mesh filter6may be very low, thereby prolonging the service life of the mesh filter6. The predetermined temperature may vary according to species and compositions of the hydrocarbon gas used in the first and second precursor gases. In some embodiments, the predetermined temperature may range from about 100° C. to about 250° C., but other ranges of values are also within the scope of this disclosure. For example, in some embodiments, the predetermined temperature may be also greater than about 250° C.

In some embodiments, after completion of the etching process, the introduction of the first and second precursor gases into the process chamber21, the heating of the substrate (W) and the heating of the process chamber21are ceased, and thus the temperature inside the process chamber21is gradually cooled down to the ambient temperature. Thereafter, the treated substrate (W) is removed from the process chamber21. In some embodiments, the vacuum pump5is continuously operated unless the apparatus1is scheduled for routine maintenance. The heating of the mesh filter6may be terminated after the vacuum pump5is shut down.

In some embodiments, some steps in the method10may be modified, replaced, or eliminated without departure from the spirit and scope of the present disclosure.

In this disclosure, by heating the mesh filter to a predetermined temperature which is closer to a processing temperature (i.e., the plasma treating temperature) in the apparatus, a gas percentage in the fluid flow passing through the heated mesh filter is significantly increased. As such, the amount of the particles and/or the solid byproducts collected by the mesh filter for each treatment in the apparatus is relatively low, and the service life of the mesh filter can be significantly prolonged, so that the frequency of the replacement of the mesh filter can be greatly reduced. In addition to reduction of cost for maintenance of the apparatus, the semiconductor devices manufactured using the apparatus may have less defects due to the particles and/or the solid byproducts being present on the apparatus in less amount, thereby improving reliability and yield of the semiconductor devices.

In accordance with some embodiments of the present disclosure, An apparatus includes a process chamber, a vacuum pump disposed downstream of the process chamber for discharging a fluid flow from the process chamber, a filter mounted between the process chamber and the vacuum pump for filtering the fluid flow, and a heating device disposed to heat the filter.

In accordance with some embodiments of the present disclosure, the filter is a mesh filter.

In accordance with some embodiments of the present disclosure, the heating device includes a heat generator for generating a heat energy, and a conduction unit configured to transmit the heat energy from the heat generator to the filter.

In accordance with some embodiments of the present disclosure, the conduction unit includes a conduction base which has an opening for passage of the fluid flow, and which is disposed downstream of the filter.

In accordance with some embodiments of the present disclosure, an outer dimension of the filter ranges from 25 cm to 45 cm, and a distance between an outer periphery and an inner periphery of the conduction base ranges from 0.5 cm to 3.0 cm.

In accordance with some embodiments of the present disclosure, the conduction unit includes a conduction base which has an opening for passage of the fluid flow. The filter is fittingly engaged in the opening of the conduction base.

In accordance with some embodiments of the present disclosure, the heating device further includes a temperature sensor disposed for detecting a temperature of the filter.

In accordance with some embodiments of the present disclosure, the heat generator further includes an electrical resistor and a controller. The electrical resistor serves for converting an electrical energy to the heat energy, and is in thermal contact with the conduction unit. The controller is in single communication with the temperature sensor and the electrical resistor, and is configured such that when the temperature of the filter is lower than a predetermined temperature, the electrical resistor is switched by the controller from an off-state to an on-state, where the electrical energy is applied to the electrical resistor.

In accordance with some embodiments of the present disclosure, an apparatus includes a housing including a process chamber for treating a substrate using a plasma, a first precursor gas introduced into the process chamber for generating the plasma, a substrate retainer disposed in the housing and configured to retain the substrate in the process chamber, so as to permit the substrate to be treated by the plasma, a vacuum pump disposed downstream of the housing for discharging a fluid flow which results from treating the substrate using the plasma, a mesh filter mounted between the housing and the vacuum pump for filtering the fluid flow, and a heating device disposed to heat the mesh filter.

In accordance with some embodiments of the present disclosure, the apparatus further includes a plasma generator for generating the plasma. The plasma generator includes a dielectric plate disposed above the substrate retainer, a first gas inlet formed in the dielectric plate and configured to introduce the first precursor gas into the process chamber, and a plasma coil disposed above the dielectric plate so as to ionize the first precursor gas to generate the plasma in the process chamber when a power is applied to the plasma coil.

In accordance with some embodiments of the present disclosure, the apparatus further includes a second precursor gas, and a plurality of second gas inlets which are formed in the housing, and which are angularly spaced apart from each other so as to introduce the second precursor gas into the process chamber through the second gas inlets, and so as to permit the second precursor gas, together with the first precursor gas, to be ionized to generate the plasma.

In accordance with some embodiments of the present disclosure, at least one of the first precursor gas and the second precursor gas includes a hydrocarbon gas.

In accordance with some embodiments of the present disclosure, the heating device includes a heat generator for generating a heat energy, and a conduction unit configured to transmit the heat energy from the heat generator to the mesh filter.

In accordance with some embodiments of the present disclosure, the apparatus further includes a throttle valve coupled between the housing and the mesh filter.

In accordance with some embodiments of the present disclosure, the housing further includes a communication chamber disposed downstream of the process chamber and upstream of the mesh filter.

In accordance with some embodiments of the present disclosure, the apparatus further includes a supporting frame which is configured to support the substrate retainer, and which is disposed inside the housing to partition an inner space of the housing into the process chamber and the communication chamber. The supporting frame is formed with a plurality of venting bores so as to permit passage of the fluid flow.

In accordance with some embodiments of the present disclosure, a method includes: treating a substrate using a plasma in a plasma chamber at a plasma treating temperature so that a fluid flow which results from treating the substrate is obtained; directing the fluid flow to sequentially pass through a communication chamber and a mesh filter, the fluid flow in the communication chamber having a cooled down temperature lower than the plasma treating temperature; and heating the mesh filter to a predetermined temperature which is higher than the cooled down temperature so as to increase a gas percentage of the fluid flow when the fluid flow passes through the mesh filter.

In accordance with some embodiments of the present disclosure, the mesh filter is heated through a thermal conductor which is in direct contact with the mesh filter, and which transmits a heat energy from a heat generator to the mesh filter.

In accordance with some embodiments of the present disclosure, the plasma is generated by ionization of a precursor gas which includes a hydrocarbon gas.

In accordance with some embodiments of the present disclosure, the mesh filter is heated to the predetermined temperature before treating the substrate using the plasma.

In accordance with some embodiments of the present disclosure, an apparatus includes a housing, a vacuum pump, a filter, and a heating device. The housing includes a process chamber. The vacuum pump is disposed downstream of the process chamber for discharging a fluid flow from the process chamber. The vacuum pump includes an inlet tube. An inner surface of the inlet tube has a first portion, a second portion located upstream of the first portion, and a shoulder portion interconnecting the first portion and the second portion. The inlet tube has a first inner dimension at the first portion, and a second inner dimension at the second portion. The second inner dimension is larger than the first inner dimension. The filter is disposed on the shoulder portion for filtering the fluid flow. The heating device is disposed to heat the filter.

In accordance with some embodiments of the present disclosure, the heating device includes a heat generator for generating a heat energy, the heat generator being disposed outside a pathway of the fluid flow, a conduction base disposed in contact with the filter, and a conduction rod extending through the inlet tube so as to bring the conduction base into thermal contact with the heat generator, and so as to transmit the heat energy from the heat generator to the filter through the conduction base and the conduction rod.

In accordance with some embodiments of the present disclosure, the conduction base has an opening for passage of the fluid flow.

In accordance with some embodiments of the present disclosure, the apparatus further includes a throttle valve for regulating a flow rate of the fluid flow entering the vacuum pump. An end face of an outlet tube of the throttle valve being in abutting engagement with an end face of the inlet tube of the vacuum pump.