Patent ID: 12203169

DETAILED DESCRIPTION

In a present embodiment, a substrate processing apparatus1is configured as a vertical substrate processing apparatus that performs a substrate processing step such as heat processing as one step of a manufacturing process in a method for manufacturing a semiconductor device.

As illustrated inFIGS.1to3, the substrate processing apparatus1includes two adjacent processing modules3A and3B. The processing module3A includes a processing furnace4A and a loading chamber6A as a first loading chamber that temporarily houses a wafer W as a substrate to be carried in and out of the processing furnace4A. The processing module3B includes a processing furnace4B and a loading chamber6B as a second loading chamber that temporarily houses a wafer W to be carried in and out of the processing furnace4B. The loading chambers6A and6B are disposed below the processing furnaces4A and4B, respectively. A transfer chamber8including a transfer machine7that transfers a wafer W is disposed adjacent to a front side of the loading chambers6A and6B. A storage chamber9that stores a pod (hoop)5that stores a plurality of wafers W is connected to a front side of the transfer chamber8. A load port10is disposed on an upper surface or a front surface of the storage chamber9, and the pod5is carried in and out of the substrate processing apparatus1via the load port10.

Gate valves13A and13B are disposed on a boundary wall (adjacent surface) between the loading chambers6A and6B and the transfer chamber8, respectively. A pressure detector is disposed in each of the transfer chamber8and the loading chambers6A and6B, and the pressure in the transfer chamber8is set so as to be lower than the pressure in each of the loading chambers6A and6B. In addition, an oxygen concentration detector is disposed in each of the transfer chamber8and the loading chambers6A and6B, and the oxygen concentration in each of the transfer chamber8and the loading chambers6A and6B is maintained so as to be lower than the oxygen concentration in the atmosphere. As illustrated inFIG.1, a clean unit11that supplies clean air into the transfer chamber8is disposed on a ceiling of the transfer chamber8, and circulates, for example, an inert gas as clean air in the transfer chamber8. By circulating and purging the inside of the transfer chamber8with an inert gas, the inside of the transfer chamber8can be made into a clean atmosphere. With such a configuration, it is possible to suppress particles and the like in the loading chambers6A and6B from being mixed into the transfer chamber8, and it is possible to suppress formation of a natural oxide film on a wafer W in the transfer chamber8and the loading chambers6A and6B.

Transfer of a wafer W to boats20A and20B is performed in the loading chambers6A and6B through the transfer chamber8, respectively. The pressure inside each of the loading chambers6A and6B is set so as to be lower than the pressure outside the substrate processing apparatus1.

A gas to be used for substrate processing is supplied into the processing chambers24A and24B by a gas supply system described later. The gas supplied by the gas supply system is changed depending on the type of film to be formed. Here, the gas supply system includes a raw material gas supplier, a reactive gas supplier, and an inert gas supplier. The gas supply system is housed in a supply box17. Note that the supply box17is disposed in common for the processing modules3A and3B, and therefore regarded as a common supply box.

The gas that has been used for substrate processing is discharged from the processing chambers24A and24B by a gas exhaust system described later. The gas exhaust system is housed in each of exhaust boxes18A and18B.

A duct50A as a first flow path and a duct50B as a second flow path are connected to furnace spaces14A and14B of the processing furnaces4A and4B, respectively. In addition, the duct50A and the duct50B merge together on a downstream side and are connected to a duct50C as a third flow path. In other words, the duct50C is a part of the duct50A and duct50B where the duct50A and the duct50B merge together and flow. In the duct50C, a radiator52as a heat exchanger, an exhaust blower54, and an factory exhaust duct55are disposed in this order from an upstream side. The radiator52cools, in a short time, a gaseous refrigerant that has cooled the furnace spaces14A and14B and reached a high temperature to a temperature at which the refrigerant can be discharged. In addition, the exhaust blower54sucks the refrigerant that has been cooled by the radiator52and sends out the refrigerant to the factory exhaust duct55on a downstream side. The radiator52and the exhaust blower54are disposed at substantially the same height toward a rear of the processing furnaces4A and4B. The duct50A, the duct50B, and the duct50C connect the furnace space14A formed inside a heater12A and the furnace space14B formed inside a heater12B to the factory exhaust duct55through the radiator52and the exhaust blower54such that the refrigerant can flow therethrough.

In addition, on upstream sides of the radiator52in the middle of the ducts50A and50B, a damper53A as a first damper having a variable opening degree and a damper53B as a second damper having a variable opening degree are disposed, respectively. The dampers53A and53B are preferably disposed in the immediate vicinity of refrigerant outlets of the furnace spaces14A and14B, respectively, in order to minimize heat escape. In this example, the ducts50A and50B merge into the duct50C downstream of the dampers53A and53B and upstream of the radiator52such that both the radiator52and the exhaust blower54are used commonly for cooling the furnace space14A and the furnace space14B.

As illustrated inFIGS.2and3, the components of the processing module3A, that is, the components in the processing furnace4A and the components in the loading chamber6A are disposed bisymmetrically and plane-symmetrically with the components of the processing module3B, that is, the components in the processing furnace4B and the components in the loading chamber6B, respectively, about an adjacent plane (boundary plane) of the processing modules3A and3B as a symmetric plane. In addition, as illustrated inFIG.2, the length of the duct50A is the same as the length of the duct50B, the duct50A and the damper53A are disposed bisymmetrically with the duct50B and the damper53B, respectively, about the duct50C, and the position of the damper53A in the duct50A is substantially the same as the position of the damper53B in the duct50B.

The radiator52and the exhaust blower54used for cooling the furnace spaces14A and14B are housed in a cooling box19. Note that the cooling box19is disposed in common for the processing modules3A and3B, and therefore regarded as a common cooling box.

To the gas supply system, the gas exhaust system, the carry system, the radiator52, the exhaust blower54, the dampers53A and53B, and the like, a controller100as a controller for controlling these is connected. The controller100is constituted by, for example, a microprocessor (computer) including a CPU, and controls operation of the substrate processing apparatus1. To the controller100, an input/output device102formed as, for example, a touch panel is connected. One controller100can be disposed in common for the processing module3A and the processing module3B.

A memory104may be a memory device (hard disk or flash memory) built in the controller100, or may be a portable external recording device (for example, a semiconductor memory such as a USB memory or a memory card). In addition, a program may be provided to the computer using a communication means such as a network. The program is read from the memory104by an instruction or the like from the input/output device102as needed, and the controller100executes a process according to a read recipe. As a result, the substrate processing apparatus1executes a desired process under control of the controller100. The controller100is housed in a controller box105. An instruction to start the recipe can be given from the outside for each processing module at a random timing.

The controller100can control opening/closing operation of the dampers53A and53B such that the cooling timing of the processing furnace4A does not overlap with the cooling timing of the processing furnace4B. For example, the controller100opens the damper53A of the processing furnace4A on a cooling side, closes the damper53B of the processing furnace4B on a non-cooling side, and switches between cooling the furnace space14A and cooling the furnace space14B. For this reason, the controller100predicts the timings of opening the dampers53A and53B next, and adjusts start times of recipes performed in the processing module3A and the processing module3B such that the open periods of the dampers53A and53B do not overlap with each other or even if the open periods of the dampers53A and53B overlap with each other, there is such a time difference that the temperature of a processing furnace of a processing module having a damper to be opened first is lowered to a predetermined temperature or lower when a damper to be opened later is opened. That is, the timings for heat processing are made different. For example, the recipes for the processing modules can proceed in opposite phases to each other. In addition, at an end of rapid cooling of the preceding recipe, the temperature of the refrigerant is low, and therefore partial overlap between the rapid cooling periods may be allowed. Adjustment of the start of the recipe is rarely needed, and independence between the processing modules is maintained to such an extent that an interfere with practical use does not occur.

Note that instead of the dampers53A and53B, a three-way valve may be disposed at a merging point of the ducts50A and50B. As the three-way valve, a valve that not only connects any two ports of the three ports to each other but also can communicate the three ports with each other at the same time and can close the three ports at the same time can be used. In this case as well, the recipes for the two processing furnaces4A and4B proceed such that a period during which the three ports communicate with each other at the same is 0 or sufficiently shorter than a rapid cooling period. By using the three-way valve instead of the dampers53A and53B, the number of parts can be reduced, and space saving and energy saving (cost reduction) can be achieved. In addition to the dampers53A and53B, the three-way valve may be further disposed. As a result, the duct50A and the duct50B can be selectively connected to the radiator52on downstream sides of the damper53A and the damper53B such that a refrigerant can flow therethrough.

The processing furnace4A and the processing furnace4B have the same configuration, and therefore will be described below as the processing furnace4.

As illustrated inFIG.4, the processing furnace4includes the heater12as a cylindrical furnace body, a cylindrical reaction tube16housed in the furnace space14inside the heater12, and the boat20that holds a wafer W to be processed in the reaction tube16. The boat20can be loaded with wafers W in multiple stages with gaps in a horizontal state, and holds the plurality of wafers W in the reaction tube16in this state. The boat20is placed on an elevator (not illustrated) via a boat cap22, and can be raised and lowered by this elevator. Therefore, loading of a wafer W into the reaction tube16and removal of a wafer W from the reaction tube16are performed by operation of the elevator. In addition, the reaction tube16forms the processing chamber24that houses a wafer W, a gas introduction tube (not illustrated) communicates with the inside of the reaction tube16, and the gas supply system is connected to the gas introduction tube. In addition, a gas exhaust pipe56communicates with the inside of the reaction tube16to exhaust the inside of the processing chamber24.

The heater12has a cylindrical shape and has a heat insulating structure in which a plurality of heat insulating bodies is laminated and a heating elements30as a heat-generating body that heat the furnace space14inside the heat insulating structure. The heating elements30is disposed inside the heater12by being divided into a plurality of zones. The heater12heats a wafer W inside the heater12to perform heat processing on the wafer W.

The heat insulating structure has a side wall32as a heat insulator formed into a cylindrical shape, and an upper wall33as a heat insulator formed so as to cover an upper end of the side wall32.

The side wall32is formed into a multilayer structure, and includes a side wall outer layer32aformed on an outer side of the plurality of layers of the side wall32and a side wall inner layer32bformed on an inner side of the plurality of layers. A cylindrical space34as a refrigerant passage is formed between the side wall outer layer32aand the side wall inner layer32b. The heating elements30is disposed inside the side wall inner layer32b, and the inside of the heating elements30serves as a furnace core. Furthermore, the side wall32has a structure in which a plurality of heat insulating bodies is laminated, but it goes without saying that the side wall32is not limited to such a structure.

In a side portion of the upper wall33or an upper portion of the side wall outer layer32a, a refrigerant supply port36that supplies a refrigerant such as air to the inside of the processing furnace4(the inside of the heater12) is formed. In addition, in a lower portion of the side wall outer layer32a, a refrigerant discharge port43that discharges a refrigerant from the inside of the processing furnace4(the inside of the heater12) is formed.

As illustrated inFIG.5A, a duct38aas a buffer area communicating with the refrigerant supply port36and the cylindrical space34is disposed at an upper end of the cylindrical space34in a substantially horizontal direction of the refrigerant supply port36. In the present embodiment, the refrigerant supply port36is disposed in an annular shape, but it goes without saying that the embodiment of the present disclosure is not limited to this form. A circular rapid cooling exhaust port40is formed on the central axis of the heater12on the upper wall33, and the rapid cooling exhaust port40is open to the furnace space14. In addition, a refrigerant discharge port42is formed on a side surface of the upper wall33above the duct38a, and communicates with the rapid cooling exhaust port40.

As illustrated inFIG.5E, a duct38bas a buffer area communicating with the refrigerant discharge port43and the cylindrical space34is disposed at a lower end of the cylindrical space34in a substantially horizontal direction of the refrigerant discharge port43. The duct38bhas an annular shape and is formed so as to have a wider cross-sectional area than the cross-sectional area of each of the refrigerant discharge port43and the cylindrical space34.

That is, ducts38aand38bas buffer areas formed so as to be wider than the cylindrical space34are disposed at both ends of the cylindrical space34.

In addition, at a boundary between the duct38aand the cylindrical space34, a throttle37ais disposed which narrows the refrigerant passage which is the cylindrical space34(reduces the cross-sectional area of the refrigerant passage) to reduce a flow rate of a refrigerant. That is, at the boundary plane between the duct38aand the cylindrical space34, as illustrated inFIG.5B, a plurality of throttle holes41ais evenly formed in a circumferential direction.

In addition, at a boundary between the duct38band the cylindrical space34, a throttle37bis disposed which narrows the refrigerant passage which is the cylindrical space34(reduces the cross-sectional area of the refrigerant passage) to reduce a flow rate of a refrigerant. That is, at the boundary plane between the duct38band the cylindrical space34, as illustrated inFIG.5D, a plurality of throttle holes41bis evenly formed in a circumferential direction.

In addition, the cross-sectional area of the throttle hole41ais larger than the cross-sectional area of the throttle hole41b. In addition, the total cross-sectional area of the plurality of throttle holes41ais smaller than each of the cross-sectional areas of the ducts38aand38b.

In addition, as illustrated inFIG.5C, in the side wall inner layer32bbelow the refrigerant supply port36, a plurality of blowout holes35communicating the cylindrical space34and the furnace space14with each other is formed in a desired distribution, and as illustrated inFIG.4, communicates the cylindrical space34and the furnace space14with each other substantially horizontally. That is, a refrigerant is blown out from the cylindrical space34to the furnace space14.

In addition, the refrigerant discharge port42and the refrigerant discharge port43are connected to the exhaust pipes45aand45b, respectively, and merge into the duct50. Specifically, the exhaust pipes45aand45bof the processing furnaces4A and4B merge into the ducts50A and50B, respectively. Then, the duct50A and the duct50B merge into the duct50C. The radiator52and the exhaust blower54are connected to the duct50C in this order from an upstream side, and the factory exhaust duct55is connected to the exhaust blower54. A heated refrigerant in the heaters12A and12B is discharged via the ducts50, the radiator52, the exhaust blower54, and the factory exhaust duct55to the outside of a clean room where the substrate processing apparatus1is disposed.

Here, a damper39a, which is a valve that can be opened and closed, is disposed near the refrigerant supply port36in the duct38a. In addition, a damper39bthat can be opened and closed is disposed near the refrigerant discharge port42and the duct50in the duct50. In addition, a damper39cthat can be opened and closed is disposed near the refrigerant discharge port43and the duct38b. Then, by disposing the dampers39band39cnear the duct50or the duct38b, an influence of convection from the duct at a discharge port when not in use can be reduced, and substrate temperature uniformity around the duct can be improved.

Furthermore, supply of a refrigerant is operated by opening/closing the damper39aand turning on/off the exhaust blower54, the cylindrical space34is closed and opened by opening/closing the damper39bor the damper39cand turning on/off the exhaust blower54, and a refrigerant is discharged from the refrigerant discharge port42or the refrigerant discharge port43.

In addition, on a downstream side of the radiator52of the duct50C and on an upstream side of the exhaust blower54, a pressure sensor131that detects the pressure on an upstream side of the exhaust blower54is disposed.

An exhaust blower control device80includes a subtractor1002, a PID calculator1004, a rotation speed converter1006, and a rotation speed indicator1008. A pressure target value S is input from a process control device81to the subtractor1002. In addition to the pressure target value S, a pressure value A measured by the pressure sensor131is input to the subtractor1002, and a deviation D obtained by subtracting the pressure value A from the pressure target value S is output from the subtractor1002. Here, the pressure target value S is such a value that an intake side of the exhaust blower54maintains a predetermined negative pressure as compared with the atmospheric pressure.

The deviation D is input to the PID calculator1004. The PID calculator1004performs PID calculation based on the input deviation D, and calculates an operation amount X. The calculated operation amount X is input to the rotation speed converter1006, converted to a rotation speed T by the rotation speed converter1006, and output. The output rotation speed T is input to an inverter132, and the rotation speed of the exhaust blower54is changed.

The pressure value A from the pressure sensor131is input to the subtractor1002at all times or at predetermined time intervals, and control of the rotation speed of the exhaust blower54is continued such that the deviation D between the pressure target value S and the pressure value A is 0 based on this pressure value A. As described above, the rotation speed of the exhaust blower54is controlled via the inverter132such that the deviation D between the pressure value A measured by the pressure sensor131and the predetermined pressure target value S disappears. A fact that the pressure A indicated by the pressure sensor131is higher than the pressure target value S indicates some abnormality, and the pressure A can be inspected on a daily basis.

Instead of calculating the rotation speed T with the PID calculator1004, by inputting the rotation speed T from the process control device81to the rotation speed indicator1008, and inputting the rotation speed T from the rotation speed indicator1008to the inverter132, the rotation speed of the exhaust blower54may be changed. In addition, instead of the pressure sensor131, a flow velocity sensor may be used to control a flow rate in the duct50C so as to be constant.

Next, an example of a film forming process performed in the processing furnace4will be described with reference toFIGS.6and7.FIG.6is a flowchart indicating an example of a temperature-related process among film forming processes performed in the processing furnace4, andFIG.7schematically illustrates a temperature change inside the furnace. Reference numerals S1to S6illustrated inFIG.7indicate that steps S1to S6inFIG.6are performed, respectively.

Step S1is a process of stabilizing the temperature inside the furnace to a relatively low temperature T0. In step S1, a wafer W has not been inserted into the furnace yet.

Step S2is a process of inserting a wafer W held by the boat20into the furnace. Since the temperature of the wafer W is lower than the temperature T0inside the furnace at this point, the temperature inside the furnace is temporarily lower than T0as a result of inserting the wafer W into the furnace. However, the temperature inside the furnace is stabilized again at the temperature T0by a temperature control device74or the like described later after a short period of time.

Step S3is a process of raising the temperature inside the furnace at a constant rate from the temperature T0to a target temperature T1for performing a film forming process on the wafer W.

Step S4is a process of maintaining and stabilizing the temperature inside the furnace at the target temperature T1in order to perform a film forming process on the wafer W.

Step S5is a process of lowering the temperature inside the furnace at a constant rate from the temperature T1to the relatively low temperature T0again after the film forming process is completed.

Step S6is a process of pulling out the wafer W that has been subjected to the film forming process together with the boat20from the inside of the furnace.

When an unprocessed wafer W to be subjected to the film forming process remains, the processed wafer W on the boat20is replaced with the unprocessed wafer W, and the series of processes in steps S1to S6are repeated.

Each of the processes in steps S1to S6obtains a stable state in which the temperature inside the furnace is within a predetermined minute temperature range with respect to a target temperature and the state continues only for a predetermined time, and then proceeds to a next step. Alternatively, recently, each of the processes in S1, S2, S5, S6, and the like proceeds to a next step without obtaining a stable state in order to increase the number of wafers W to be subjected to a film forming process in a certain period of time.

In the reaction tube16, first temperature sensors27-1,27-2,27-3, and27-4that detect the temperature of the substrate are disposed in parallel with the boat20in order from an upper part in the reaction tube16. The first temperature sensors27-1,27-2,27-3, and27-4are used as substrate temperature sensors that detect temperatures corresponding to the temperatures of wafers W in heater zones U, CU, CL, L from above the heater12, respectively.

In addition, in the furnace space14, second temperature sensors70-1,70-2,70-3, and70-4that detect a heater temperature are disposed in parallel with the reaction tube16in order from above in the furnace space14. The second temperature sensors70-1,70-2,70-3, and70-4are used as heater temperature sensors that detect temperatures corresponding to the temperatures of the furnace space or the heating elements30in the heater zones U, CU, CL, and L from above the heater12, respectively.

Next, a process when the temperature inside the furnace is suitable will be described.

When the temperature inside the furnace is suitable and stable, all of the dampers39a,39b, and39care closed and the exhaust blower54is also stopped (furnace temperature stable control state). At this time, a refrigerant in the cylindrical space34, which is a refrigerant passage, is in a stationary state having a high energy saving effect. That is, it is in a state of step S4(during film forming process for a wafer W) inFIGS.6and7.

Next, a rapid cooling process for rapidly cooling the inside of the furnace will be described.

At the time of rapid cooling, the damper39cis closed, the damper39ais opened, and the damper39bis opened to operate the exhaust blower54(rapid cooling control state). A refrigerant supplied from the refrigerant supply port36is uniformized at the throttle37avia the duct38aand then introduced into the cylindrical space34. The refrigerant introduced into the cylindrical space34descends in the cylindrical space34and is introduced into the furnace space14via the blowout hole35. The refrigerant introduced into the furnace space14rises in the furnace space14, is discharged from the refrigerant discharge port42via the rapid cooling exhaust port40, and cools the heating elements30from both an outer surface and an inner surface. That is, the heated refrigerant in the heater12is discharged to the outside via the refrigerant discharge port42to lower the temperature in the heater12. That is, it is in a state of step S5(after film forming process of a wafer W and before boat unloading) inFIGS.6and7. Such a rapid cooling process can be executed at the time of cooling a wafer after the film forming process is completed, at the time of boat unloading, at the time of wafer discharge, at the time of forcibly peeling and removing a deposited film, and the like. A temperature falling rate of the rapid cooling process is equal to or more than 5 times that of natural cooling, for example, 15° C./min or more.

Next, a process for recovering the temperature inside the furnace will be described.

At the time of temperature recovery, the damper39bis closed, the damper39ais opened, and the damper39cis opened to operate the exhaust blower54(control state at the time of temperature recovery). A refrigerant supplied from the refrigerant supply port36is uniformized in the throttle37avia the duct38a, then supplied to the cylindrical space34, uniformized in the throttle37bwithout passing through the furnace space14or the rapid cooling exhaust port40, and then discharged from the refrigerant discharge port43via the duct38b. As described above, by cooling the side wall32while the heating elements30generate Joule heat, a peak of a radiation spectrum in the heater12is shifted to a high temperature side, and a wafer W at a furnace core is effectively heated.

The temperature control device74controls opening/closing of the dampers39a,39b, and39cby a damper control device82and rotation of the exhaust blower54by the exhaust blower control device80according to the above-described temperature control modes such as the furnace temperature stable control state, the rapid cooling control state, and the control state at the time of temperature recovery. As a result, it is possible to achieve both temperature recovery characteristics and reduction of power consumption while favorable substrate temperature uniformity is maintained. That is, the controller100controls heating of the heating elements30in the heater zones U, CU, CL, and L by the heater drive devices76-1to76-4, opening/closing of the dampers39a,39b, and39cby the damper control device82, opening/closing of the dampers53A and53B by the damper control device82, rotations of the radiator52and the exhaust blower54, and the like such that a wafer W is subjected to heat processing at an independent timing in each of the heaters12A and12B. That is, the controller100adjusts the opening degrees of the dampers39band39cin the heaters12A and12B, and cools the heaters12A and12B having different temperatures at a common predetermined temperature falling rate.

FIG.8is a diagram schematically illustrating a configuration of the controller100that controls the substrate processing apparatus1and a relationship between the controller100and the processing furnace4.

As illustrated inFIG.8, the controller100includes a flow rate control device78, the temperature control device74, the heater drive devices76-1,76-2,76-3, and76-4, the exhaust blower control device80, the damper control device82, and the process control device81.

The flow rate control device78adjusts the flow rate of a gas supplied into the processing chamber24by the gas flow rate regulator62based on a detection result by the flow rate sensor64. The gas flow rate regulator62adjusts the flow rate of a gas introduced into the reaction tube16via a gas introduction nozzle (not illustrated). The flow rate sensor64measures the flow rate of the gas supplied into the reaction tube16via the gas introduction nozzle.

The temperature control device74divides the heater12into four regions of the heater zones U, CU, CL, and L from above, and controls the heater drive devices76-1,76-2,76-3, and76-4corresponding to the heater zones U, CU, CL, and L, respectively. Specifically, the temperature control device74controls the heater drive device76-1based on detection temperatures detected by the first temperature sensor27-1and the second temperature sensor70-1disposed in the heater zone U. The other zones are controlled similarly.

The damper control device82controls the opening degrees of the dampers39a,39b, and39cand opening/closing of the dampers53A and53B according to a temperature control mode (recipe) determined by the process control device81. In addition, in a predetermined temperature control mode other than the rapid cooling control state, the damper control device82controls the damper39band the like using an opening degree provided by the temperature control device74.

The exhaust blower control device80controls the rotation speed of the exhaust blower54based on a pressure value detected by the pressure sensor131.

The controller100controls each component of the semiconductor manufacturing device as the substrate processing apparatus1based on a temperature and values of pressure and flow rate set by the memory104or the input/output device102with these components. As a control method performed inside the controller100, so-called cascade control as illustrated inFIG.9is usually used. InFIG.8, a method for calculating a control output inside of the temperature control device74is illustrated in a block diagram. A target temperature obtained from the process control device81is input to an input terminal S.

Next, a control method performed inside the temperature control device74will be described with reference toFIG.9. Note that each of a set temperature, an input terminal S, an input terminal A, an input terminal B, and an output terminal F is present for the number of the first temperature sensors27-1,27-2,27-3, and27-4. Set temperatures in the heater zones U, CU, CL, and L are input from the process control device81to the input terminals S, respectively. Substrate temperatures obtained from the first temperature sensors27-1,27-2,27-3, and27-4are input to the input terminals A, respectively. Heater temperatures obtained from the second temperature sensors70-1,70-2,70-3, and70-4are input to the input terminals B, respectively.

FIG.9illustrates a cascade control loop for the heater zone U.

The temperature control device74includes a subtractor521, a PID calculator522, a subtractor523, a PID calculator524, a filter525, a subtractor526, a PD calculator527, a converter528, and a reference table529.

A set temperature S of the heater zone U is input to the subtractor521from the process control device81. In addition to the set temperature S, a detection temperature A detected by the first temperature sensor27-1is input to the subtractor521, and a deviation C obtained by subtracting the detection temperature A from the set temperature S is output by the subtractor521.

The deviation C is input to the PID calculator522. The PID calculator522performs PID calculation based on the input deviation C, and calculates an operation amount D. The calculated operation amount D is input to the subtractor523.

A detection temperature B detected by the second temperature sensor70-1is input to the subtractor523, and a deviation E obtained by subtracting the detection temperature B from a target temperature with respect to a heater temperature based on the operation amount D is output by the subtractor523.

The deviation E is input to the PID calculator524. The PID calculator524performs PID calculation based on the input deviation E, and calculates an operation amount F.

The calculated operation amount F is input to the heater drive device76-1. The heater drive device76-1adjusts a conduction angle of a thyristor based on the input operation amount F, and controls the amount of power (supply power) to the heating elements30in the heater zone U.

Similarly, the heater drive devices76-2,76-3, and76-4control the amount of power (supply power) to the heating elements30in the heater zones CU, CL, and L based on the operation amount F calculated by using the set temperatures, the input terminals S, the input terminals A, and the input terminals B in the heater zones CU, CL, and L, respectively.

In addition, the operation amount F is input to the subtractor526via the filter525. The filter525is a filter that smooths the operation amount F in a time domain and outputs the smoothed amount as an operation amount f, and can calculate a smoothed value based on the operation amount F for one cycle or more at a resonance frequency of a control system. Note that when a negative operation amount F is input, the operation amount f of 0 may be output immediately. A reference quantity G is input to the subtractor526from the reference table529.

The reference table529stores the operation amount F in a stable state, for example, for each zone and each set temperature, and outputs the operation amount F as a reference amount. Note that the reference amount can be continuously adjusted so as to converge rapidly according to a state such as the furnace temperature stable control state, a temperature elevating state at a constant rate, a temperature falling state at a constant rate, or a transition state between these states. For example, when a state transits from the temperature elevating state at a constant rate to the furnace temperature stable control state, the reference amount can be temporarily reduced in order to improve responsiveness by performing heating and cooling at the same time. In addition, in the furnace temperature stable control state, the reference amount can be set to a large value such that cooling does not easily operate.

A deviation H obtained by subtracting the operation amount f from the reference quantity G is output by the subtractor526. A positive deviation H suggests that the heater should be cooled.

The deviation H is input to the PD calculator527. The PD calculator527performs PD calculation based on the input deviation H, and calculates an operation amount I.

The calculated operation amount I is converted into the opening degree of the damper39bby the converter528. Note that a negative operation amount I is converted to 0 (fully closed), and an operation amount I equal to or more than a predetermined value is converted to fully open. Then, the damper control device82controls the opening degree of the damper39bbased on the converted opening degree.

In this example, the opening degree of the damper39buses the operation amount F in the heater zone U to the heating elements30as a control amount, but may use an operation amount in another heater zone. For example, a weighted average value of the operation amounts F in the heater zones U, CU, CL, and L to the heating elements30may be used as a control amount. Note that an actual operation amount (supply power) in the heater zone U to the heating elements30is a non-negative value, but the operation amount F can also be negative.

As described above, the controller100can control, for each of the heater zones U, CU, CL, and L, the heat generation amount of the heating elements30in each of the heater zones while referring to the detected temperatures of the second temperature sensor70-1to70-4such that the detected temperatures of the first temperature sensors27-1to27-4follow target values. In addition, at the time of rapid cooling or the like, the controller100can adjust the opening degrees of the damper39band the damper39cwith reference to the detected temperatures of the second temperature sensors70-1and70-4such that the detected temperatures of the first temperature sensors27-1to27-4follow target values.

MODIFICATION EXAMPLE

Some Modification Examples will be described below.

Modification Example 1

FIG.10Ais a top view schematically illustrating an example of heaters12A and12B of a substrate processing apparatus according to Modification Example 1.

As illustrated inFIG.10A, ducts50A and50B are connected to the insides of the heaters12A and12B, respectively. In addition, the duct50A and the duct50B merge together on a downstream side and are connected to a duct50C. In the duct50C, a high-performance radiator152and a high-performance exhaust blower154are disposed in this order from an upstream side. In addition, on an upstream side of the radiator152in the middle of the ducts50A and50B, dampers53A and53B having variable opening degrees are disposed, respectively. That is, the ducts50A and50B merge into the duct50C, and both the high-performance radiator152and the high-performance exhaust blower154are commonly used for rapid cooling the heaters12A and12B. In this Modification Example, by using the high-performance radiator152and the high-performance exhaust blower154, the dampers53A and53B can be opened at the same time, and the heaters12A and12B can be rapidly cooled at the same time. At this time, it is preferable to use a radiator152or the like having sufficient performance such that a desired temperature falling rate can be obtained without fully opening the damper53A and the damper53B. As a result, it is not needed to adjust start time of a recipe, and independence between processing modules3A and3B is guaranteed. In addition, for example, even when the damper53A is opened, the damper53B is closed, and only the heater12A is rapidly cooled, rapid cooling time can be shortened.

Modification Example 2

FIG.10Bis a top view schematically illustrating an example of heaters12A and12B of a substrate processing apparatus according to Modification Example 2.

As illustrated inFIG.10B, ducts50A and50B are connected to the insides of the heaters12A and12B, respectively. In addition, the duct50A and the duct50B merge together on a downstream side and are connected to a duct50C. In the duct50C, a high-performance exhaust blower154is disposed. In addition, radiators52A and52B are disposed in the ducts50A and50B, respectively. In addition, on upstream sides of the radiators52A and52B in the middle of the ducts50A and50B, dampers53A and53B having variable opening degrees are disposed, respectively. That is, the ducts50A and50B merge into the duct50C, and the high-performance exhaust blower154is commonly used for rapid cooling the heaters12A and12B. In this Modification Example, by using the high-performance exhaust blower154, the dampers53A and53B can be opened at the same time, and the heaters12A and12B can be rapidly cooled in parallel.

Modification Example 3

FIG.10Cis a top view schematically illustrating an example of heaters12A and12B of a substrate processing apparatus according to Modification Example 3.

As illustrated inFIG.10C, ducts50A and50B are connected to the heaters12A and12B, respectively. In addition, the duct50A and the duct50B merge together in the middle and are connected to a duct50C. The duct50A includes a duct50A-1on an upstream side of the duct50C and a duct50A-2on a downstream side of the duct50C. The duct50B includes a duct50B-1on an upstream side of the duct50C and a duct50B-2on a downstream side of the duct50C. In the ducts50A-1and50B-1, dampers53A-1and53B-1having variable opening degrees are disposed, respectively. In the ducts50A-2and50B-2, exhaust blowers54A and54B are disposed, respectively. On upstream sides of the exhaust blowers54A and54B of the ducts50A-2and50B-2, dampers53A-2and53B-2having variable opening degrees are disposed, respectively. In the duct50C, a high-performance radiator152is disposed. That is, the ducts50A and50B merge into the duct50C, and the radiator152is commonly used for rapid cooling the heaters12A and12B. In this Modification Example, since the high-performance radiator152is used, the dampers53A-1and53A-2and the dampers53B-1and53B-2are opened at the same time, and the heaters12A and12B can be rapidly cooled at the same time.

COMPARATIVE EXAMPLE

FIG.10Dis a top view schematically illustrating an example of a processing furnace of a substrate processing apparatus according to Comparative Example.

As illustrated inFIG.10D, ducts50A and50B are connected to heaters12A and12B, respectively. In addition, in the ducts50A and50B, radiators52A and52B and exhaust blowers54A and54B are disposed, respectively. In addition, on upstream sides of the radiators52A and52B in the middle of the ducts50A and50B, dampers53A and53B having variable opening degrees are disposed, respectively. That is, each of the heaters12A and12B includes a radiator52and an exhaust blower54.

That is, according to the present embodiment and Modification Examples, since the number of parts is smaller than that of Comparative Example, it is possible to save space and energy in the substrate processing apparatus.

According to the present embodiment, the following one or more effects can be obtained.

1) It is possible to achieve contradictory conditions for a high throughput and space-saving between a plurality of processing furnaces, and to rapidly reduce the temperature inside the furnace. In particular, the radiator52and the exhaust blower54can be miniaturized by shifting a progress of a recipe among the plurality of processing modules such that simultaneous rapid cooling from a maximum process temperature does not occur.

2) Since at least one of a radiator and an exhaust blower is shared by the plurality of processing furnaces, space saving and resource saving can be achieved by removing the equipment, the number of inspection points is reduced, and maintenance is also easy.

3) Even if a part or the whole of a rapid cooling period overlaps between the plurality of processing furnaces, rapid cooling can be performed at a determined temperature falling rate, the quality of a film formed on a wafer can be made equivalent, and a thermal history of the reaction tube16can be made equivalent.

4) By disposing components bisymmetrically about a boundary surface of processing modules as a symmetric plane, it is possible to suppress variations in the quality of film formation between the left and right processing modules. In addition, film formation can be performed on the left and right processing modules under similar conditions, and the quality of the film formation can be made uniform. Therefore, productivity can be improved. Furthermore, by disposing ducts and dampers connected to processing modules bisymmetrically about a duct into which these ducts merge, it is possible to suppress variations in the quality of the film formation between the left and right processing modules. In addition, film formation can be performed on the left and right processing modules under similar conditions, and the quality of the film formation can be made uniform. Therefore, productivity can be improved.

According to this present disclosure, even when two processing furnaces are included, space can be saved by removing needed equipment.