SUBSTRATE PROCESSING APPARATUS AND METHOD OF MANUFACTURING SEMICONDUCTOR DEVICE

There is provided a technique that includes a plurality of first coolers installed in or around a process furnace configured to process a substrate, and configured to perform cooling by a cooling fluid; a second cooler installed in or around the process furnace and configured to perform cooling by the cooling fluid, the second cooler being not included in the plurality of first coolers; a distributor configured to distribute the cooling fluid supplied from a cooling fluid supply port to the plurality of first coolers and an auxiliary system bypassing the plurality of first coolers; and a merging part configured to merge the cooling fluid passed through the plurality of first coolers and the cooling fluid passed through the auxiliary system, respectively, and supply the merged cooling fluid to the second cooler.

CROSS-REFERENCE TO RELATED APPLICATION

This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2021-044447, filed on Mar. 18, 2021, the entire contents of which are incorporated herein by reference.

TECHNICAL FIELD

The present disclosure relates to a substrate processing apparatus and a method of manufacturing a semiconductor device.

BACKGROUND

According to a related art, in a method of manufacturing a semiconductor device, a substrate processing apparatus for performing a predetermined process by heating the inside of a process furnace may be used, and cooling water may be allowed to flow to cooling-required points of the heated process furnace to perform cooling.

The required flow rate of cooling water differs depending on the cooling units arranged at the cooling-required points. When there are multiple cooling units, if the flow rate of the cooling water supplied to one of the cooling units is increased, due to the opening and closing of a valve for the cooling water supplied to the cooling unit having a large flow rate of cooling water, the flow rate of the cooling water supplied to other cooling units adjusted to a constant flow rate may fluctuate in some cases. In addition, there is a demand to reduce the total consumption of cooling water.

SUMMARY

Some embodiments of the present disclosure provide a technique capable of stably supplying cooling fluid to multiple cooling units while reducing the total consumption of the cooling fluid.

According to one embodiment of the present disclosure, there is provided a technique that includes a plurality of first coolers installed in or around a process furnace configured to process a substrate, and configured to perform cooling by a cooling fluid; a second cooler installed in or around the process furnace and configured to perform cooling by the cooling fluid, the second cooler being not included in the plurality of first coolers; a distributor configured to distribute the cooling fluid supplied from a cooling fluid supply port to the plurality of first coolers and an auxiliary system bypassing the plurality of first coolers; and a merging part configured to merge the cooling fluid passed through the plurality of first coolers and the cooling fluid passed through the auxiliary system, respectively, and supply the merged cooling fluid to the second cooler.

DETAILED DESCRIPTION

Hereinafter, embodiments will be described with reference to the drawings. It should be noted that the drawings used in the following description are schematic and the relationship between the dimensions of respective elements, the ratio of respective elements, and the like shown in the drawings do not always match the actual ones. In addition, even among the plurality of drawings, the relationship between the dimensions of respective elements, the ratio of respective elements, and the like do not always match.

(1) CONFIGURATION OF SUBSTRATE PROCESSING APPARATUS

As shown inFIGS. 1 and 2, the substrate processing apparatus1includes a housing13. A front maintenance port15as an opening for maintenance is provided at a lower portion of a front wall14of the housing13. The front maintenance port15is opened and closed by a front maintenance door16.

A pod loading/unloading port17is provided on the front wall14of the housing13to bring the inside and outside of the housing13in fluid communication with each other. The pod loading/unloading port17is opened and closed by a front shutter18. A load port19is installed in front of the pod loading/unloading port17. The load port19is configured to align a pod21mounted thereon.

The pod21is a closed-type substrate container. The pod21is carried on the load port19by an in-process transfer device (not shown) and is also carried out from the load port19.

A rotary pod shelf22is installed at an upper portion in a substantially central portion in a front-rear direction in the housing13. The rotary pod shelf22is configured to store a plurality of pods21. Further, a spare pod shelf23is installed in the front maintenance port15below the load port19. The spare pod shelf23is configured to store a plurality of pods21.

The rotary pod shelf22includes a support column24that is vertically erected and intermittently rotated, and a plurality of shelf boards25that are radially supported on the support column24at the respective positions of the upper, middle and lower stages. Each of the shelf boards25is configured to store a plurality of pods21in a mounted state.

A pod opener26is installed below the rotary pod shelf22. The pod opener26is configured to mount the pod21thereon and open and close a lid of the pod21.

A pod transfer device27is installed between the load port19, the rotary pod shelf22, and the pod opener26. Further, the pod transfer device27can hold the pod21and can move up and down, move forward and backward, and move laterally. The pod transfer device27is configured to transfer the pod21between the load port19, the rotary pod shelf22, and the pod opener26.

A sub-housing28is installed over a rear end in a lower portion of the housing13on a rear side in the front-rear direction. On the front wall29of the sub-housing28, a pair of wafer loading/unloading ports32for loading and unloading the wafer (substrate)31with respective to the sub-housing28are arranged vertically in two upper and lower stages. A pod opener26is installed for each of the upper and lower wafer loading/unloading ports32.

The pod opener26includes a mounting table33on which the pod21is mounted, and an opening/closing mechanism34for opening and closing the lid of the pod21. The pod opener26is configured to open and close the wafer inlet/outlet of the pod21by opening and closing the lid of the pod21mounted on the mounting table33by the opening/closing mechanism34.

The sub-housing28constitutes a delivery chamber (loading area)35kept airtight from the space (pod transfer space) in which the pod transfer device27and the rotary pod shelf22are arranged. A delivery machine (wafer transfer mechanism)36is installed in a front region of the delivery chamber35. The delivery machine36has a required number of (five, in the figure) wafer mounting plates (substrate support)37for holding wafers31. The wafer mounting plates37can move linearly in a horizontal direction, can rotate in the horizontal direction, and can move up and down in the vertical direction. The delivery machine36is configured to charge and discharge the wafers31into and out of a boat (substrate holder)38.

A heater chamber45is installed above the delivery chamber35with a scavenger74interposed therebetween. A vertical process furnace12is installed in the heater chamber45. The process furnace12forms a process chamber therein. The lower furnace opening of the process chamber is located in the scavenger74. The lower end of the furnace opening is opened and closed by a furnace opening shutter41.

A boat elevator42for raising and lowering the boat38is installed on a side surface of the sub-housing28. A seal cap44as a lid is horizontally attached to an arm43connected to the lift of the boat elevator42. The seal cap44vertically supports the boat38and airtightly closes the furnace operation portion in a state in which the boat38is loaded into the process furnace12. The boat38is configured to hold a plurality of (e.g., about 50 to 175) wafers31at in multiple stages in a horizontal posture in a state in which the wafers31are aligned with the center of the boat38.

A cleaner (not shown) is arranged at a position facing the boat elevator42side. The cleaner is composed of a supply fan and a dustproof filter so as to supply a clean atmosphere or a clean air which is an inert gas. A notch alignment device (not shown) as a substrate matching device for aligning circumferential positions of the wafers31is installed between the delivery machine36and the cleaner.

Next, the operation of the substrate processing apparatus1will be described.

When the pod21is supplied to the load port19, the pod loading/unloading port17is opened by the front shutter18. The pod21on the load port19is loaded into the housing13by the pod transfer device27through the pod loading/unloading port17and is placed on the designated shelf board25of the rotary pod shelf22. The pod21is temporarily stored in the rotary pod shelf22. Then, the pod21is transferred from the shelf board25to one of the pod openers26by the pod transfer device27and mounted on the mounting table33or is directly transferred from the load port19to the mounting table33.

An opening side end surface of the pod21mounted on the mounting table33is pressed against the opening edge of the wafer loading/unloading port32on the front wall29of the sub-housing28. The lid of the pod21is removed by the opening/closing mechanism34to open the wafer inlet/outlet port.

When the pod21is opened by the pod opener26, the delivery machine36takes out the wafer31from the pod21and charges the wafer31into the boat38. The delivery machine36that has delivered the wafer31to the boat38returns to the pod21and charges the next wafer31into the boat38.

When a predetermined number of wafers31are charged to the boat38, the furnace opening of the process furnace12closed by the furnace opening shutter41is opened by the furnace opening shutter41. Subsequently, the boat38is lifted by the boat elevator42and loaded into the process furnace12.

After loading the boat38, an arbitrary process is performed on the wafer31in the process furnace12. After performing the process, the wafer31and the pod21are carried out of the housing13by the reverse procedure of the above procedure.

(2) CONFIGURATION OF PROCESS FURNACE (AIR COOLING SYSTEM)

FIG. 3is a vertical sectional view showing the process furnace12and the surroundings thereof. The process furnace12includes a reaction tube203having a cylindrical shape and configured to be loaded with the boat38, a liner tube204configured to accommodate the reaction tube203therein, a heat insulating wall300configured to internally form a cylindrical reaction tube accommodation chamber205as an example of a reactor accommodation chamber for accommodating the liner tube204and composed of a side surface heat insulating material300A for forming the side wall surface of the reaction tube accommodation chamber205and a ceiling surface insulating material300B for forming a ceiling surface of the reaction tube accommodation chamber205, a heater206installed on the inner wall of the reaction tube accommodation chamber205in the heat insulating wall300, an air flow path302formed concentrically with the inner wall surface of the reaction tube accommodation chamber205inside the side surface heat insulating material300A and the heater206installed on the inner wall of the reaction tube accommodating chamber205in the heat insulating wall300to extend in the vertical direction, an upper chamber304configured to fluid communicate with the air flow path302at the upper end of the air flow path302and form a part of an air circulation path306described later, a lower chamber308configured to fluid communicate with the air flow path302at the lower end of the air flow path302and form a part of the air circulation path306described later, and an air circulation path306configured to bring the upper chamber304and the lower chamber308into communication with each other.

The lower chamber308is installed with an intake valve310, which is an on-off valve in fluid communicate with the outside air.

On the other hand, a radiator312as an example of an air cooling means is installed near the upper chamber304on the air circulation path306, and a fan314as an example of an air flow means is installed near the lower chamber308.

An on-off valve316is installed between the upper chamber304and the radiator312in the air circulation path306, and an on-off valve318is installed between the fan314and the lower chamber308. An exhaust valve320, which is an on-off valve in fluid communicate with the equipment exhaust system, and an intake valve322, which is an on-off valve in fluid communicate with the outside air, are installed between the radiator312and the fan314. Further, an exhaust valve324, which is an on-off valve in fluid communicate with the equipment exhaust system, is installed between the fan314and the on-off valve318, and an on-off valve326is installed between the exhaust valve320and the intake valve322.

In the process furnace12, the intake valves310and322and the on-off valve318correspond to first valves of the present disclosure, and the exhaust valve320and324and the on-off valve316correspond to second valves of the present disclosure.

That is, the process furnace12includes an air cooling system that circulates an air, which is a heat medium for cooling the furnace body.

Further, in the process furnace12, there are installed a gas introduction pipe line328for introducing a precursor gas or/and an inert gas into the reaction tube203and a gas discharge pipe line330for discharging the precursor gas or/and the inert gas introduced into the reaction tube203to the outside of the reaction tube203. Below the process furnace12, an inlet flange332is arranged concentrically with the reaction tube203. An O-ring as a seal is installed between the inlet flange332and the reaction tube203. The gas introduction pipe line328and the gas discharge pipe line330are installed so as to penetrate the side wall of the inlet flange332.

On the opposite side of the seal cap44from the inside of the reaction tube203, a boat rotator334for rotating the boat38accommodating the wafers31is installed. A rotation shaft335of the boat rotator334is formed to penetrate the seal cap44and is connected to the boat38. The boat rotator334is configured to rotate the wafers31by rotating the boat38.

(3) CONFIGURATION OF WATER COOLING SYSTEM

Next, the water cooling system preferably used in one embodiment of the present disclosure will be described with reference toFIG. 4.

The water cooling system400supplies a cooling fluid (brine) such as cooling water or the like to a plurality of units as cooling-required points of the substrate processing apparatus1to thereby cool the respective units.

The water cooling system400mainly includes a supply pipe404, a water supply side manifold408as a distributor, a plurality of first coolers including a first unit440, a second unit442, a third unit444and a fourth unit446, an auxiliary system described later, a water drainage side manifold450as a merging part, a water drainage pipe452, and a second cooler including a fifth unit456.

In the supply pipe404, a valve406, which is an on-off valve or a control valve, is installed at a connection portion connected to factory equipment that provides a cooling fluid. The valve406is, for example, a globe valve or a ball valve, and can be used for finely adjusting the total amount of the cooling fluid among a plurality of substrate processing apparatuses1or for shutting off the cooling fluid during maintenance.

The water supply side manifold408distributes the cooling fluid supplied from the cooling fluid supply port402to the first unit440, the second unit442, the third unit444, the fourth unit446, and the pipe418which is an auxiliary system.

The water drainage side manifold450merges the cooling fluid that have passed through the first unit440, the second unit442, the third unit444, the fourth unit446, and the pipe418, and supplies the merged cooling fluid to the fifth unit456through the water drainage pipe452.

Pipes410,412,414,416, and418are connected in parallel between the water supply side manifold408and the water drainage side manifold450.

In the pipes410,412,414, and416, needle valves420,422,424, and426, flow meters430,432,434, and436, a first unit440, a second unit442, a third unit444, and a fourth unit446are installed sequentially from the upstream side. The first unit440, the second unit442, the third unit444, and the fourth unit446supply the cooling fluid in parallel. In this regard, the needle valves420,422,424, and426are control valves that are automatically opened and closed by a controller600and are configured so that the opening degree described later can be continuously changed by electric control. After adjusting the flow rate so as to secure the required flow rate for each unit, the needle valves are operated in a fixed state, and the controller600monitors the flow rate of the flow meter. The controller600is configured to generate an alarm or automatically readjust the flow rate when the monitored flow rate deviates from a predetermined range. As used herein, the term “required flow rate” refers to a flow rate required to maintain each unit or its cooling target at a desired temperature or lower.

Further, a needle valve428is installed in the pipe418. That is, the pipe418is configured to directly connect the water supply side manifold408and the water drainage side manifold450via the needle valve428. The pipe418may be used as an auxiliary system in which the needle valve428is opened and closed to bypass the first to fourth units through which the cooling fluid flows from the water supply side manifold408to the water drainage side manifold450. As described below, the flow rate in the pipe418can be set to minimize the energy consumed for air cooling and water cooling.

A heat exchanger454, a fifth unit456, a flow meter458and a valve460are installed in the water drainage pipe452sequentially from the upstream side. The heat exchanger454is installed between the water drainage side manifold450and the fifth unit456to cool the cooling fluid. The heat exchanger454is configured to cool the cooling fluid merged in the water drainage side manifold450by the heat exchange with an ambient air or a gas (high concentration inert gas) discharged from the delivery chamber35to the equipment exhaust system. The valve460can be used similarly to the valve406. The heat exchanger454does not have to be installed. For example, if the pipe between the water drainage side manifold450and the first to fourth units and the fifth unit456is long enough to obtain the low water temperature required for cooling the fifth unit456, the heat exchanger454may be omitted. In this case, the flow rate of the cooling fluid may be increased by controlling the needle valve428of the pipe418which is an auxiliary system.

The first unit440, the second unit442, the third unit444, and the fourth unit446cool different objects, and at least one of them cools the furnace opening of the process furnace12. The first unit440, the second unit442, the third unit444, and the fourth unit446are units provided in or around the process furnace12for processing the wafers31and configured to perform cooling by a cooling fluid having a small flow rate.

The fifth unit456is a cooler provided in or around the process furnace12for processing the wafer31and configured to cool, by using a cooling fluid having a large flow rate, the furnace body of the process furnace12or the air or the like as a heat medium which has been used for cooling the furnace body. In other words, the fifth unit456has the largest required flow rate of the cooling fluid or the largest amount of heat discharged to the cooling fluid among the first unit440, the second unit442, the third unit444, the fourth unit446, and the fifth unit456.

The amount of heat received by the cooling fluid in the fifth unit456per unit time varies depending on the temperature of the process furnace12and the temperature lowering rate. That is, the fifth unit456cools an object having a fluctuating heat reception amount and performs heat exchange between the furnace body or the air and the cooling fluid. The air or the like heated by the furnace body heats the surroundings while being discharged to the equipment exhaust system and accelerates the failure of electronic devices and the outgassing of impurities such as phosphorus and the like. Therefore, the air or the like heated by the furnace body is preferably cooled by the fifth unit456immediately after flowing out from the process furnace12. Further, the sufficiently cooled air can be used for cooling again, the air discharged by air cooling can be reduced, and the energy consumed for the air can be reduced.

The first unit440, the second unit442, the third unit444, and the fourth unit446are used to cool, for example, the furnace opening of the process furnace12, the inlet flange332, the seal cap44, the boat rotator334, the casing of the process furnace12, the atmosphere in the delivery chamber35, and the like.

For example, an embedded flow path for a cooling fluid is formed in the inlet flange332and is configured to cool the O-ring or the like that seals the furnace opening of the process furnace12. Further, the seal cap44, the boat rotator334, the casing of the process furnace12, the delivery chamber, and the like are configured to be cooled by the cooling fluid flowing around them. Moreover, the radiator that cools the atmosphere in the transfer chamber35may be cooled by the cooling fluid. In addition, it may be possible to use a cooling jacket capable of being attached to a portion that requires cooling.

The fifth unit456is, for example, a radiator312, and is configured to cool the air flowing in the process furnace12when the process furnace12is rapidly cooled. In the auxiliary system, the opening degree of the needle valve428is set semi-fixedly according to the maximum amount of heat received by the radiator312, and the air after passing through the radiator312is kept at a predetermined temperature or lower. Alternatively, the opening degree of the needle valve428can be changed according to a change in the amount of heat received by the radiator312, and the opening degree of the needle valve428can be set to zero except during rapid cooling. This makes it possible to save the use amount of the cooling fluid while substantially maintaining the cooling capacity when rapidly cooling the process furnace12. An on-off valve may be installed in series with the needle valve428in order to switch the amount of water in the auxiliary system according to the operating status of the fifth unit456. In that case, the auxiliary system has a pipe418, a needle valve428and an on-off valve.

That is, the water cooling system400distributes the cooling fluid introduced from the cooling fluid supply port402to the five pipes410,412,414,416, and418via the needle valve406and the water supply side manifold408.

Then, the cooling fluid distributed to the pipes410,412,414, and416flow through the first unit440, the second unit442, the third unit444, and the fourth unit446via the needle valves420,422,424, and426and the flow meters430,432,434, and436, respectively, and merge at the water drainage side manifold450. In addition, the cooling fluid distributed to the pipe418flows through the needle valve428and merges at the water drainage side manifold450.

Then, the cooling fluid merged in the water drainage side manifold450passes through the fifth unit456and returns to the factory equipment via the flow meter458and the valve460.

That is, the cooling fluid supplied to the first unit440, the second unit442, the third unit444, and the fourth unit446having a small flow rate are merged and supplied to the fifth unit456having a maximum flow rate. As a result, the use amount of the cooling fluid can be reduced as compared with the case where the cooling fluid are supplied in parallel to all the units. Further, the fluctuation of the flow rate of the cooling fluid of the entire substrate processing apparatus1can be reduced as compared with the case where the supply of the cooling fluid of the fifth unit456is turned on and off in order to save the cooling fluid. Thus, the cooling fluid can be stably supplied to each unit, and the water hammer phenomenon and the pipe damage and water leakage caused by the water hammer phenomenon can be suppressed.

In this regard, the minimum required flow rate of the cooling fluid of the fifth unit456is preferably not more than the total value of the minimum required flow rates of the first unit440, the second unit442, the third unit444, and the fourth unit446. As a result, the use amount of cooling fluid can be minimized usually without having to use the auxiliary system.

If the total value of the required flow rates of the cooling fluid in the first unit440, the second unit442, the third unit444, and the fourth unit446is less than the required flow rate of the cooling fluid in the fifth unit456, the cooling fluid can be replenished by adjusting the opening degree of the needle valve428of the pipe418in the auxiliary system. The cold cooling fluid from the pipe418of the auxiliary system that bypasses the cooling unit can lower the temperature of the cooling fluid in the fifth unit456.

As described above, by adopting the cascade structure for supplying water to the respective units, it is possible to reduce the total consumption of the cooling fluid used in the water cooling system400.

Further, even when the water is saved in the water cooling system400, it is possible to maintain a minute flow rate without setting the flow rate of the cooling fluid to 0 in all the pipes. This makes it possible to prevent the cooling fluid from decaying, algae from breeding, and rust from accumulating. Further, it is indicated in the SEMI/ISMI standard S23 as an energy conversion factor (ECF) that energy saving is achieved when the flow rate of the cooling fluid is reduced even if the total amount of heat discharged to the cooling fluid does not change. That is, in the case of cooling water (25 degrees C. or higher) supplied from a cooling tower, energy consumption is determined by the used flow rate, regardless of the rise in water drainage temperature. Even in the case of cooling water (less than 25 degrees C.) supplied from a chiller, energy consumption depends on the used flow rate. In the process furnace12according to the present disclosure, the air from the process furnace12is cooled by the cooling fluid. Therefore, as the flow rate of the cooling fluid is increased, the circulating air is cooled and the amount of air introduced from the outside and the amount of exhaust are reduced.

(4) CONFIGURATION OF CONTROLLER

The substrate processing apparatus1includes a controller600that controls the operation of each part of the substrate processing apparatus1.

The outline of the controller600is shown inFIG. 5. The controller600, which is a control part (control means), is configured as a computer including a CPU (Central Processing Unit)600a, a RAM (Random Access Memory)600b, a memory600cand an I/O port600d. The RAM600b, the memory600cand the I/O port600dare configured to exchange data with the CPU600avia an internal bus600e. An input/output device602configured as, for example, a touch panel or the like, and an external memory device603such as a thumb memory or the like may be connected to the controller600.

The memory600cis composed of, for example, a flash memory, an HDD (Hard Disk Drive), or the like. The memory600creadably stores a control program for controlling the operation of the substrate processing apparatus1, a process recipe in which a procedure and conditions for a substrate processing process described later, and the like. The process recipe is configured to cause the controller600to execute each procedure in the substrate processing process described later and obtain a predetermined result. The process recipe functions as a program. Hereinafter, the process recipe, the control program, and the like are collectively and simply referred to as a program. When the term program is used in the subject specification, it may include a process recipe, a control program alone, or both. The RAM600bis configured as a memory area (work area) in which programs, data, and the like read by the CPU600aare temporarily held.

The I/O port600dis connected to the pod transfer device27, the delivery machine36, the boat elevator42, the heater206, the radiator312, the fan314, the intake valves310and322, the exhaust valves320and324, the on-off valves316,318and326, the needle valves420,422,424,426and428, the flow meters430,432,434,436and458, the valves406and460, the heat exchanger454, and the like.

The CPU600ais configured to read the control program from the memory600cand execute the same and is configured to read the process recipe from the memory600cin response to the input of an operation command from the input/output device602or the like. The CPU600ais configured to control, according to the content of the process recipe thus read, the pod transfer operation performed by the pod transfer device27, the delivery operation of the wafer31performed by the delivery machine36, the raising and lowering operation of the boat38performed by the boat elevator42, the rotating operation of the boat38performed by the boat rotator334, the temperature adjustment operation of the heater206, the opening/closing operations of the intake valves310and322, the on-off valves316,318, and326and the exhaust valves320and324, the start and stop of the radiator312and the fan314, the opening/closing operations of the needle valves420,422,424,426, and428and the valves406and460, the flow rate adjustment operation for the cooling fluid performed by the flow meters430,432,434,436, and458, the start and stop of the heat exchanger454, and the like.

(5) SUBSTRATE PROCESSING PROCESS USING SUBSTRATE PROCESSING APPARATUS

Next, a sequence example of a process of forming a film on the wafer31(hereinafter also referred to as a film-forming process) using the above-mentioned substrate processing apparatus1will be described as a semiconductor device manufacturing process. Here, an example of forming a film on the wafer31by supplying a precursor gas to the wafer31will be described. In the following description, the operation of each part constituting the substrate processing apparatus1is controlled by the controller600.

(S10: Wafer Charging and Boat Loading)

First, the standby state of the apparatus is released, a plurality of wafers31is charged to the boat38(wafer charging), and the boat38is loaded into the process furnace12by the boat elevator42(boat loading).

Vacuum exhaust (Depressurization exhaust) is performed by the vacuum pump provided in the gas discharge pipe line330so that the inside of the reaction tube203, i.e., the space where the wafers31exists, has a predetermined pressure (vacuum degree). At this time, the pressure in the reaction tube203is measured by the pressure sensor, and the APC valve is feedback-controlled based on the measured pressure information. The vacuum pump is always kept in operation until at least the processing of the wafers31is completed.

Further, the inside of the reaction tube203is heated by the heater206so that the wafers31in the reaction tube203have a predetermined temperature. At this time, the supply of electric power to the heater206is feedback-controlled based on the temperature information detected by a temperature detector so that an inside of the reaction tube203has a predetermined temperature distribution. The heating in the reaction tube203by the heater206is continuously performed at least until the processing of the wafers31is completed.

The controller600closes the intake valve310, the on-off valve316and the on-off valve318until the temperature inside the reaction tube203, i.e., the temperature of the wafers31, reaches a target temperature after the temperature rise of the wafers31is started. At this time, a predetermined amount of cooling fluid is circulated in the radiator312. On the other hand, from the viewpoint of reducing power consumption, it is preferable that the on-off valve320and the exhaust valves320and324are also closed and the fan314is stopped.

As a result, the air flow path302is out of communication with the outside air and the equipment exhaust system, so that the air flow in the air flow path302is also stopped. Not only the heat insulating material forming the heat insulating wall300, but also the air in the air flow path302functions as a heat insulating material, whereby the temperature inside the reaction tube203rises rapidly.

When the temperature in the reaction tube203is maintained at the preset processing temperature, a precursor gas is supplied to the wafers31in the reaction tube203. The precursor gas introduced into the reaction tube203through the gas introduction pipe line328flows down in the reaction tube203and flows out to the outside of the reaction tube203via the gas discharge pipe line330. When passing through the reaction tube203, the precursor gas comes into contact with the surfaces of the wafers31, so that the wafers31are subjected to, for example, oxidation, diffusion, or the like.

In this step, the temperature rise in step S12, which has been continued during the film-forming process, is stopped, and the temperature inside the reaction tube203is rapidly dropped.

The controller600opens the on-off valve316to start the operation of the fan314and opens the intake valve310, the on-off valve326, and the exhaust valve324. As a result, the air as a heat medium flowing out of the air flow path302and cooled by the radiator312is sucked and discharged from the exhaust valve324to the equipment exhaust system (equipment exhaust duct). Alternatively, the intake valve322and the exhaust valve320installed between the radiator312and the fan314are opened, the air introduced from the intake valve322is pumped into the air flow path302, and the air flowing out of the air flow path302and cooled by the radiator312is discharged. In the case of the former flow route, the exhaust temperature discharged to the equipment exhaust system can be lowered by opening the on-off valve326and the intake valve322and mixing the air having a room temperature with the discharged air. In the latter flow route, the amount of the air discharged to the equipment exhaust system can be reduced by opening the on-off valve326to circulate a part or the entirety of the air. The controller600optimally controls the flow route, the speed of the fan314, and the opening degrees of the intake valves310and322, the exhaust valves320and324and the on-off valve326so that the temperature of the reaction tube accommodation chamber205is reduced at a desired rate and the amount of the introduced or discharged air is minimized while keeping the temperature of the air discharged to the equipment exhaust system (equipment exhaust duct) and the temperature of the air in the fan314at a predetermined level or lower.

At this time, the water cooling system400is controlled by the controller600so that the cooling fluid introduced from the cooling fluid supply port402is distributed to five units through the supply pipe404, the needle valve406and the water supply side manifold408, and the cooling fluid passed around the furnace opening, the inlet flange332, the seal cap44, the boat rotator334, and the like are merged in the water drainage side manifold450and supplied to the radiator312. As a result, the cooling fluid is supplied to the radiator312to exchange heat with the air flowing through the air circulation path306, so that the air in the process furnace12is cooled. When the total flow rate of the cooling fluid supplied through the vicinity of the furnace opening of the process furnace12, the inlet flange332, the seal cap44, the boat rotator334, and the like is less than the flow rate required for the radiator312, the opening degree of the needle valve428of the pipe418in the auxiliary system is adjusted. When the temperature of the merged cooling fluid is high, the radiator312exchanges heat between the air as a heat medium and the cooling fluid, thereby lowering the temperature of the cooling fluid.

The controller600can further perform optimal control between the air cooling system and the water cooling system400to minimize energy consumption. The energy consumption C and the heat H that can be dissipated at the time of rapid cooling are expressed as follows.

Here, Uairand Uwaterare the use amounts of air and water used [m3], respectively, Uair=0.1507 [kWh/m3], and Uwater=0.26 [kWh/m3]. H is a function of Uairand Uwater, which is used as a constant value in order to obtain a desired temperature drop rate, and the relationship between Uairand Uwateris empirically obtained. Uairand Uwaterthat minimize C can be solved numerically by Lagrange's undetermined multiplier method or the like. Further, ECFairand ECFwaterare the above-mentioned energy conversion coefficients, which are coefficients for calculating the energy consumed during the use of the apparatus, and are defined in the SEMI/ISMI standard S23. In the present embodiment, ECFairis the sum of the energy (0.147 kWh/m3) required to prepare clean dry air in a clean room and the energy (0.0037 kWh/m3) required for exhaust. ECFwateris the energy required to prepare (supply and recover) the circulating cooling water, which is equivalent to the electricity bill for the cooling tower and the circulation pump.

In addition, an analytical solution can be obtained by modeling g (Uair, Uwater) as follows.

In the above equation, a, b, c and d represent constants. The controller600can control the speed of the fan314, the opening degree of the needle valve428, and the like so as to match the Uairand Uwaterthus obtained.

When the preset processing time elapses, an inert gas is supplied through the gas introduction pipe line328, so that the inside of the reaction tube203is replaced with the inert gas and the pressure in the reaction tube203is returned to the atmospheric pressure. Steps S14and S15may be performed in parallel, or the starting order thereof may be changed.

(S16: Boat Unloading and Wafer Discharging)

The boat38is slowly lowered by the boat elevator42, and the lower end of the inlet flange332is opened. Then, the processed wafers31are unloaded from the lower end of the inlet flange332to the outside of the reaction tube203while being supported by the boat38(boat unloading). The processed wafers31are discharged from the boat38by the delivery machine36(wafer discharging).

(6) OTHER EMBODIMENTS

Next, a modification of the process furnace according to one embodiment of the present disclosure will be described with reference toFIG. 7. Now, the differences from the above-described embodiment will be mainly described, and the description of other points will be omitted.

The process furnace72is not provided with an air circulation path306that brings the upper chamber304and the lower chamber308into communication with each other.

An exhaust flow path706is connected to the upper chamber304. A radiator712A and a radiator712B are installed in the exhaust flow path706. An on-off valve316is installed between the upper chamber304and the radiator712A in the exhaust flow path706.

The radiator712B is supplied with the cooling fluid from the pipe418, which is an auxiliary system in the water cooling system400described above. The cooling fluid that has cooled the radiator712B and passed through the pipe418as the auxiliary system, and the cooling fluid flowing through the first unit440, the second unit442, the third unit444and the fourth unit446at a small flow rate are merged and supplied to the radiator712A. As a result, the cooling fluid is supplied to the radiators712A and712B to exchange heat with the air which is a heat medium flowing through the exhaust flow path706, and the cooled air is exhausted. That is, in this modification, a merging part for merging the cooling fluid flowing through the first unit to the fourth unit is installed in the radiator712A.

Even when the above-mentioned process furnace72is used, the film formation can be performed under the same substrate processing process and processing conditions as when the above-mentioned process furnace12is used, and the same effects as those of the above-described embodiment can be obtained.

In the above-described embodiment, there has been described an example of forming a film using the substrate processing apparatus, which is a batch type vertical apparatus for processing a plurality of substrates at one time. However, the present disclosure is not limited thereto. The present disclosure may also be suitably applied to a case in which a film is formed using a single-substrate type substrate processing apparatus that processes one or several substrates at one time. That is, even when a single-substrate type substrate processing apparatus is used, the substrate processing process can be performed under the same processing procedure and processing conditions as those in the above-described embodiment, and the same effects as those of the above-described embodiment can be obtained.

Further, it is preferable that the recipe used in the substrate processing process is individually prepared according to the processing content and stored in the memory600cvia a telecommunication line or an external memory device603. Then, when starting the substrate processing process, it is preferable that the CPU600aappropriately selects an appropriate recipe from a plurality of recipes stored in the memory600caccording to the content of the substrate processing process. This makes it possible to form films having various film types, composition ratios, film qualities, and film thicknesses with good reproducibility by one substrate processing apparatus. In addition, the burden on the operator can be reduced, and the process can be started quickly while avoiding operation mistakes.

The above-mentioned recipe is not limited to the newly prepared one but may be prepared, for example, by modifying an existing recipe already installed in the substrate processing apparatus. When changing the recipe, the changed recipe may be installed on the substrate processing apparatus via a telecommunication line or a recording medium in which the recipe is recorded. In addition, the input/output device602included in the existing substrate processing apparatus may be operated to directly change the existing recipe already installed in the substrate processing apparatus.

According to the present disclosure in some embodiments, it is possible to stably supply a cooling fluid to multiple cooling units while reducing the total consumption of the cooling fluid.