JP4783029B2 - Heat treatment apparatus and substrate manufacturing method - Google Patents

Description

  The present invention relates to a heat treatment apparatus for heat treating a semiconductor wafer, a glass substrate or the like, and a substrate manufacturing method for producing a substrate such as a semiconductor wafer or glass.

  Conventionally, vertical heat treatment apparatuses have been widely used for heat treatment of semiconductor wafers and glass substrates. As for the temperature control of the processing chamber in this heat treatment apparatus, it is known that the heating temperature is measured by a thermocouple provided between the outer tube and the heater, and the heater is feedback-controlled based on the measurement result ( For example, Patent Document 1).

JP 2003-249456 A

However, there is a problem that temperature control is not performed accurately when the processing chamber is rapidly cooled.
This is because during the rapid cooling, the processing chamber was cooled by creating an air flow outside the process tube using a blower, so that the thermocouple temperature detector received the air flow earlier than the processing chamber. This is considered to be because of the difference between the actual processing chamber temperature and the measured temperature of the thermocouple.

  An object of the present invention is to provide a heat treatment apparatus and a substrate manufacturing method capable of solving the above-described conventional problems and accurately controlling the temperature in a reaction tube.

  The first feature of the present invention is that the reaction tube, the heater for heating the substrate, the first temperature measuring means provided outside the reaction tube, and the second temperature measurement provided outside the reaction tube. When the substrate is processed in the reaction tube, the temperature in the reaction tube is controlled based on at least the temperature detected by the first temperature measuring device, and when the reaction tube is rapidly forcedly cooled, at least the second temperature The heat treatment apparatus has control means for controlling to control the temperature in the reaction tube based on the temperature detected by the measurement means.

  The second feature of the present invention is that the step of carrying the substrate into the reaction tube, the step of raising the temperature in the reaction tube to the processing temperature, the step of processing the substrate at the processing temperature in the reaction tube, and the reaction Including a step of rapidly forcibly cooling the tube, the step of lowering the temperature in the reaction tube from the processing temperature to a temperature lower than the processing temperature, and a step of unloading the processed substrate from the processing chamber, In the process, the temperature in the reaction tube is controlled based on at least the temperature detected by the first temperature measuring means, and in the forced cooling process in the temperature lowering process, the reaction is performed based on the temperature detected by at least the second temperature measuring means. It is in the manufacturing method of the board | substrate which performs temperature control in a pipe | tube.

  Preferably, the first temperature measuring means is a thermocouple, and the second temperature measuring means is a radiation thermometer.

  Further, preferably, a means for supplying a cooling gas (air, nitrogen, etc.) to the reaction tube, a flow path for flowing the gas through the entire reaction tube, and the flowing gas are discharged. And the first temperature measuring means and the second temperature measuring means are arranged in a gas flow path.

  Preferably, the reaction tube is a single tube made of SiC.

  When the reaction tube is suddenly forcibly cooled, the temperature in the reaction tube is not affected by the cooling gas by controlling the temperature in the reaction tube based on at least the temperature detected by the second temperature measuring means. Control can be performed accurately.

Next, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows an example of a heat treatment apparatus 10 according to an embodiment of the present invention. This heat treatment apparatus 10 is a batch type vertical heat treatment apparatus, and has a housing 12 in which a main part is arranged. A pod stage 14 is connected to the front side of the housing 12, and the pod 16 is conveyed to the pod stage 14. The pod 16 stores, for example, 25 substrates, and is set on the pod stage 14 with a lid (not shown) closed.

  A pod transfer device 18 is arranged on the front side in the housing 12 at a position facing the pod stage 14. Further, a pod shelf 20, a pod opener 22, and a substrate number detector 24 are arranged in the vicinity of the pod transfer device 18. The pod shelf 20 is disposed above the pod opener 22, and the substrate number detector 24 is disposed adjacent to the pod opener 22. The pod carrying device 18 carries the pod 16 among the pod stage 14, the pod shelf 20, and the pod opener 22. The pod opener 22 opens the lid of the pod 16, and the number of substrates in the pod 16 with the lid opened is detected by the substrate number detector 24.

  Further, a substrate transfer device 26, a notch aligner 28, and a substrate support (boat) 30 are disposed in the housing 12. The substrate transfer machine 26 has, for example, an arm (tweezer) 32 that can take out five substrates. By moving this arm 32, a pod placed at the position of the pod opener 22, a notch aligner 28, and a substrate support. The substrate is transferred between the tools 30. The notch aligner 28 detects notches or orientation flats formed on the substrate and aligns the notches or orientation flats of the substrate at a certain position.

  Further, a reaction furnace 40 is disposed at the upper part on the back side in the housing 12. The substrate support 30 loaded with a plurality of substrates is carried into the reaction furnace 40 and subjected to heat treatment.

  An example of the reaction furnace 40 is shown in FIG. The reaction furnace 40 has a reaction tube 42 formed of a single tube made of silicon carbide (SiC). The reaction tube 42 has a cylindrical shape in which the upper end is closed and the lower end is opened, and the opened lower end is formed in a flange shape. A quartz adapter 44 is disposed below the reaction tube 42 so as to support the reaction tube 42. The adapter 44 has a cylindrical shape with an open upper end and a lower end, and the open upper end and the lower end are formed in a flange shape. The lower surface of the lower end flange of the reaction tube 42 is in contact with the upper surface of the upper end flange of the adapter 44. A heater 46 is disposed around the reaction tube 42 excluding the adapter 44.

  The lower part of the reaction furnace 40 is opened to insert the substrate support 30, and this open part (furnace port part) abuts the lower surface of the lower end flange of the adapter 44 with the furnace port seal cap 48 sandwiching the O-ring. So that it is sealed. The furnace port seal cap 48 supports the substrate support 30 and is provided so as to move up and down together with the substrate support 30. A quartz-made first cap 52 and a silicon carbide (SiC) second cap 50 disposed on the upper portion of the first cap 52 are provided between the furnace port seal cap 48 and the substrate support 30. And are provided. The substrate support 30 supports a large number of substrates 54 in a substantially horizontal state with a plurality of steps with gaps, and is loaded into the reaction tube 42.

  In order to enable processing at a high temperature of 1200 ° C. or higher, the reaction tube 42 is made of silicon carbide (SiC). When the SiC reaction tube 42 is extended to the furnace port portion and the furnace port portion is sealed by the furnace port seal cap 48 via the O-ring, the heat transferred through the SiC reaction tube 42 is used. There is a possibility that the temperature of the seal portion becomes high and the O-ring that is a seal material is melted. If the seal part of the reaction tube 42 made of SiC is cooled so as not to melt the O-ring, the reaction tube 42 made of SiC is damaged due to a difference in thermal expansion due to a temperature difference. Therefore, the heating region by the heater 46 is configured by the reaction tube 42 made of SiC, and the portion outside the heating region by the heater 46 is configured by the adapter 44 made of quartz, so that heat is transmitted from the reaction tube 42 made by SiC. It is possible to seal the furnace port without melting the O-ring and damaging the reaction tube 42. Further, if the seal between the SiC reaction tube 42 and the quartz adapter 44 is improved in both surface accuracy, a temperature difference occurs because the SiC reaction tube 42 is disposed in the heating region of the heater 46. Without thermal expansion. Therefore, the flange portion at the lower end of the reaction tube 42 made of SiC can be kept flat, and no gap is formed between the adapter 44 and the sealing property can be obtained simply by placing the reaction tube 42 made of SiC on the adapter 44 made of quartz. Can be secured.

  The adapter 44 is provided with a gas supply port 56 and a gas exhaust port 58 integrally with the adapter 44. A gas introduction pipe 60 is connected to the gas supply port 56, and an exhaust pipe 62 is connected to the gas exhaust port 58. A gas introduction path 64 that communicates with the gas supply port 56 and extends in the vertical direction is provided on the side wall portion (thick portion) of the adapter 44, and a nozzle mounting hole is provided at an upper portion thereof so as to open upward. Yes. A nozzle 66 is inserted and fixed in the nozzle mounting hole. That is, the nozzle 66 is connected to the upper surface of the adapter 44. With this configuration, the nozzle connection portion is not easily deformed by heat and is not easily damaged. Further, there is an advantage that the assembly and disassembly of the nozzle 66 and the adapter 44 are facilitated. The processing gas introduced from the gas introduction pipe 60 to the gas supply port 56 is supplied into the reaction pipe 42 through the gas introduction path 64 and the nozzle 66 provided in the side wall portion of the adapter 44. The nozzle 66 is configured to extend along the inner wall of the reaction tube 42 to above the substrate arrangement region (above the substrate support 30).

  In addition, as shown in FIG. 2, a heat insulating cover 68 is provided on the upper and side portions of the reaction furnace 40, and the heater 46 and the reaction tube 42 provided inside the upper heat insulating cover 68 and the side heat insulating cover 68 are provided. Between them, a cooling air passage 72 for circulating a cooling air 70 which is a cooling gas (air, nitrogen, etc.) is formed so as to entirely surround the reaction tube 42. An air supply pipe 74 that supplies the cooling air 70 to the cooling air passage 72 is disposed near the lower end of the heater 46, and the cooling air 70 supplied to the air supply pipe 74 is diffused over the entire circumference of the cooling air passage 72. It has become. Further, an exhaust port 76 for discharging the cooling air 70 from the cooling air passage 72 is formed at the center of the upper heat insulating cover 68, and an exhaust passage 78 is connected to the exhaust port 76, and a blower 80 is connected to the exhaust passage 78. Is provided. The cooling air 70 supplied from the air supply pipe 74 is exhausted by the blower 80 through the cooling air passage 72, the exhaust port 76, and the exhaust passage 78.

  The heater 46 described above has, for example, five heater parts (a first heater part 46a, a second heater part 46b, a third heater part 46c, a fourth heater part 46d, and a fifth heater part 46e in order from the top of the reaction furnace 40). The temperature can be set and adjusted for each. Each heater part 46a-46e is implement | achieved by pulling out several taps from the coil | winding of the one continuous heater 46, or providing five heaters which respectively have an independent coil | winding. Each of these heater parts 46a-46e is comprised so that sequence control may mutually be carried out in cooperation and independently by the control apparatus mentioned later. In addition, the side part heat insulation cover 68 mentioned above is five (the 1st heat insulation cover part 68a, the 2nd heat insulation cover part 68b, the 3rd heat insulation cover in order from the upper part of the reaction furnace 40 so as to correspond to each heater part 46a-46e. Part 68c, fourth heat insulating cover part 68d, and fifth heat insulating cover part 68e).

  The cooling air passage 72 of the reaction furnace 40 is provided with a thermocouple 82 as first temperature measuring means for measuring the ambient temperature in the vicinity of the outer wall of the reaction tube 42. For example, five thermocouples 82 correspond to the vertical positions of the heater portions 46a to 46e (in order from the top of the reactor 40, the first thermocouple 82a, the second thermocouple 82b, the third thermocouple). 82c, fourth thermocouple 82d and fifth thermocouple 82e). The thermocouples 82a to 82e are inserted from the outside of the heater 46 and the side heat insulating cover 68 toward the inside of the reaction furnace 40 so as to penetrate the heater 46 and the side heat insulating cover 68. It is arranged near the outer wall of the reaction tube 42.

  Furthermore, a radiation thermometer 84 is provided in the cooling air passage 72 of the reaction furnace 40 as a second temperature measuring means for measuring the temperature of the outer wall of the reaction tube 42. This radiation thermometer 84 has, for example, five (in order from the top of the reaction furnace 40, the first radiation thermometer 84a, the second radiation thermometer 84b, the first radiation thermometer 84) so as to correspond to the vertical positions of the heater portions 46a to 46e. 3 radiation thermometer 84c, 4th radiation thermometer 84d, 5th radiation thermometer 84e). The radiation thermometers 84a to 84e are inserted from the outside of the heater 46 and the side heat insulating cover 68 toward the inside of the reaction furnace 40 so as to penetrate the heater 46 and the side heat insulating cover 68. It is arrange | positioned in the outer wall vicinity.

  The heater 86a to 46e, the thermocouples 82a to 82e, and the radiation thermometers 84a to 84e described above are connected to the control device 86. The thermocouples 82a to 82e and the radiation thermometers 84a to 84e are connected to the controller 86, respectively. Transmits the measurement results to the control device 86, respectively. The control device 86 feedback-controls each heater part 46a-46e by the temperature detected by at least one of each thermocouple 82a-82e and each radiation thermometer 84a-84e. That is, the control device 86 obtains an error between the target temperature of each heater unit 46a to 46e and the temperature detected by at least one of each thermocouple 82a to 82e and each radiation thermometer 84a to 84e, and there is an error. The feedback control that eliminates the error is executed.

Next, the operation of the heat treatment apparatus 10 configured as described above will be described.
First, when a pod 16 containing a plurality of substrates is set on the pod stage 14, the pod 16 is transferred from the pod stage 14 to the pod shelf 20 by the pod transfer device 18 and stocked on the pod shelf 20. Next, the pod 16 stocked on the pod shelf 20 is transported and set to the pod opener 22 by the pod transport device 18, the lid of the pod 16 is opened by the pod opener 22, and the pod 16 is detected by the substrate number detector 24. The number of substrates accommodated in the sensor is detected.

  Next, the substrate is transferred from the pod 16 at the position of the pod opener 22 by the substrate transfer machine 26 and transferred to the notch aligner 28. The notch aligner 28 detects notches while rotating the substrates, and aligns the notches of the plurality of substrates at the same position based on the detected information. Next, the substrate is transferred from the notch aligner 28 by the substrate transfer machine 26 and transferred to the support 30.

  Thus, when one batch of substrates is transferred to the substrate support 30, the substrate support 30 filled with a plurality of substrates is loaded into the reaction furnace 40 set at a temperature of about 600 ° C., for example. (Substrate carrying-in step) The inside of the reaction furnace 40 is sealed with the furnace port seal cap 48. Next, the furnace temperature is raised to the heat treatment temperature (temperature raising step), and the reaction is performed from the gas introduction pipe 60 through the gas introduction port 56, the gas introduction path 64 provided in the side wall of the adapter 44, and the nozzle 66. Process gas is introduced into the tube 42. The processing gas includes nitrogen, argon, hydrogen, oxygen, hydrogen chloride (HCl), dichloroethylene (C2H2Cl2, abbreviated as DCE), and the like. When heat-treating the substrate, the substrate is heated to a temperature of, for example, about 1350 ° C. or more (substrate processing step). During this time, while the temperature in the reaction tube 42 is monitored based on the temperature detected by at least one of the thermocouples 82a to 82e and the radiation thermometers 84a to 84e, a preset temperature rising sequence and heat treatment sequence are set. Then, the heaters 46a to 46e are controlled to perform heat treatment.

  When the heat treatment of the substrate is finished, for example, the temperature in the furnace is lowered to a temperature of about 600 ° C. (temperature lowering step). In this temperature lowering process, when the furnace temperature is rapidly cooled, the cooling air 70 is supplied from the air supply pipe 74 to the cooling air passage 72 and is exhausted from the exhaust port 76 through the exhaust passage 78 by the blower 80. That is, the flow of the cooling air 70 is created near the outer wall of the reaction tube 42, and the reaction tube 42 is rapidly cooled (forced cooling step). Thereafter, the substrate support 30 that supports the substrate after the heat treatment is unloaded from the reaction furnace 40 (unloading step). The substrate support 30 is put on standby at a predetermined position until all the substrates supported by the substrate support 30 are cooled. Also during the temperature lowering step, the temperature in the reaction tube 42 is monitored based on the temperature detected by at least one of the thermocouples 82a to 82e and the radiation thermometers 84a to 84e, and a preset temperature decreasing sequence is followed. The heaters 46a to 46e are controlled to lower the temperature. The temperature rise sequence, the heat treatment sequence, and the temperature fall sequence are controlled by the controller 86.

  Next, when the substrate of the substrate support 30 that has been put on standby is cooled to a predetermined temperature, the substrate transfer device 26 takes out the substrate from the substrate support 30 and puts it into the empty pod 16 set on the pod opener 22. Transport and store. Next, the pod 16 is transferred by the pod transfer device 18 to the pod shelf 20 or the pod stage 14 to complete.

  Next, the temperature control pattern described above will be described in detail with reference to FIG.

  3A shows an example of a temperature sequence, FIG. 3B shows an example of temperature measuring means used in each sequence of FIG. 3A, and FIG. 3C shows each sequence of FIG. 3A. Each process corresponding to is shown.

  First, a plurality of substrates are loaded on the substrate support 30 in a plurality of stages with a gap in a substantially horizontal state (wafer charging step). Next, the substrate support 30 is loaded into the reaction tube 42 set at a temperature of 600 ° C. while controlling the heater 46 based on the temperature detected by the thermocouple 82 (boat loading step), and then The furnace temperature is raised to a temperature of about 1000 ° C. while controlling the heater 46 based on the temperature detected by the thermocouple 82 (first temperature raising step). When the furnace temperature reaches a temperature of about 1000 ° C., the temperature in the furnace is raised to a temperature of about 1350 ° C. while changing the temperature increase rate and controlling the heater 46 based on the temperature detected by the thermocouple 82. (Second temperature raising step). At this time, the rate of temperature increase in the first temperature raising step is made larger than that in the second temperature raising step. When the furnace temperature reaches a temperature of about 1350 ° C., the process gas is introduced into the reaction furnace while maintaining the furnace temperature at a temperature of about 1350 ° C. while controlling the heater 46 based on the temperature detected by the thermocouple 82. Then, the substrate is heat-treated (annealing step). After the heat treatment is completed, the temperature in the furnace is lowered to a temperature of about 1000 ° C. while controlling the heater 46 based on the temperature detected by the thermocouple 82 (first temperature lowering step).

  Next, when the furnace temperature reaches a temperature of about 1000 ° C., the temperature in the furnace is increased to a temperature of about 600 ° C. while controlling the heater 46 based on the temperature detected by the radiation thermometer 84 by changing the temperature drop rate. The temperature is lowered (second temperature lowering step). At this time, the temperature lowering rate of the second temperature lowering process (forced cooling process) is made larger than that of the first temperature lowering process. That is, in this second temperature lowering step (forced cooling step), in order to lower the furnace temperature in a short time, a flow of cooling air is created outside the reaction tube 42 to forcibly and rapidly cool the reaction tube. . Thereafter, when the temperature in the furnace reaches about 600 ° C., the substrate support tool is maintained in a state where the temperature in the furnace is maintained at about 600 ° C. while controlling the heater 46 based on the temperature detected by the thermocouple 82. 30 is unloaded from the reaction furnace 40 (boat unloading), and the substrate is taken out of the substrate support 30 (wafer discharge).

  As shown in FIG. 3B, the wafer charge process, boat loading process, furnace temperature raising process (first temperature raising process, second temperature raising process), annealing process, first temperature lowering process, boat unloading described above. The furnace temperature in the process and wafer discharge process is controlled based on the temperature detected by, for example, a thermocouple, while the furnace temperature in the second temperature lowering process (forced cooling process) is controlled by a radiation thermometer. This is performed based on the temperature detected by.

  Thus, by using the radiation thermometer for measuring the furnace temperature in the second temperature lowering process (forced cooling process), the furnace temperature can be measured without being affected by the cooling gas. That is, when a thermocouple is used for measuring the temperature in the furnace in the second temperature lowering process (forced cooling process), the thermocouple is quickly cooled by the cooling air flowing in the furnace, and the actual temperature in the furnace and the measured temperature of the thermocouple are measured. And there is a difference. Therefore, the temperature in the reaction tube can be measured more accurately without being affected by the cooling air by detecting the temperature of the reaction tube by detecting the heat radiation from the reaction tube using a radiation thermometer. .

Therefore, in the forced cooling process in the temperature lowering process, by controlling the temperature in the reaction tube based on the temperature detected by the radiation thermometer, it is possible to appropriately measure the temperature of the reaction tube and realize more accurate temperature control. it can.
Note that temperature control may also be performed based on the temperature detected by the radiation thermometer in processes other than the second temperature lowering process (forced cooling process).

  In the present embodiment, two types of temperature measuring means (thermocouple and radiation thermometer) are used for temperature control in the reaction tube. Differences in the characteristics of the thermocouple and radiation thermometer will be described.

  First, the followability (responsiveness) of a thermocouple and a radiation thermometer will be described with reference to FIG.

  FIG. 4 shows the measured temperature in the furnace when the temperature is raised, FIG. 4 (a) is a graph showing the responsiveness of the thermocouple and the radiation thermometer, and FIG. 4 (b) is a graph of FIG. 4 (a). It is the graph which expanded the part.

  The temperature of the heater was controlled by a controlled thermocouple, and a temperature increase test was performed from 600 ° C. to 1000 ° C. under a temperature increase rate of 30 ° C./min. The radiation thermometer is placed near the measurement object in the furnace and measures the temperature from the thermal radiation of this measurement object. The contact thermocouple measures the temperature by contacting the temperature detection part directly to this measurement object. did. Further, the ambient temperature in the vicinity of the measurement object was measured with a B-type thermocouple and an R-type thermocouple. The contact thermocouple is a value measured directly in the furnace with a thermocouple.

  As shown in FIG. 4B, the measurement result of the radiation thermometer confirmed the same followability (responsiveness) as the measurement result of the contact thermocouple in which the temperature detection unit was directly brought into contact with the measurement object. That is, the radiation thermometer is a non-contact temperature measurement with respect to an object to be measured, but it cannot follow with a thermocouple (R-type thermocouple, B-type thermocouple) because it has good followability (responsiveness) in temperature change. Overshoot could be detected. From this, by using the temperature detected by the radiation thermometer for temperature control in the furnace, it is possible to realize temperature control with better responsiveness compared to a thermocouple. The temperature error in the graphs of FIGS. 4 (a) and 4 (b) can be removed by software, so the overshoot in the furnace at the end of the temperature rise and the temperature curve detected by the radiation thermometer Indicate that the radiation thermometer can measure the temperature in the furnace with good responsiveness.

  Next, temperature measurement errors of the radiation thermometer and the thermocouple will be described.

  In the heat treatment apparatus in the present embodiment, quartz cannot be used for the reaction tube at high temperature treatment, particularly at 1200 ° C. or higher, and SiC is used, so the measurement object of the radiation thermometer is SiC. The emissivity of SiC is about 0.80 to 0.85, and this change in emissivity becomes a temperature measurement error in the radiation thermometer.

A general expression relating to a temperature measurement error of the radiation thermometer is expressed by the following expression 1.
(Measurement wavelength [μm] x square of measurement temperature [K] / coefficient) x emissivity fluctuation rate [%] (1)
For example, when measuring a temperature of 1300 ° C., a temperature measurement error by a radiation thermometer is calculated.
Each condition in this example is:
Measurement wavelength: 0.995 [μm]
Measurement temperature: 1573.15 [K] (1300 + 273.15)
Coefficient: 14388
Emissivity fluctuation rate: 3 [%] (change of 0.25 against emissivity 0.825)
And
Substituting these conditions into one set,
(0.995 × 1573.15 ² /14338)×0.03
Thus, the temperature measurement error of the radiation thermometer is about 5.1 ° C.

  On the other hand, the temperature error in the thermocouple (R type) is generally ± 1.5 ° C. or ± 0.25%. Similarly to the above, when a temperature measurement error due to a thermocouple is calculated at a temperature measurement of 1300 ° C., for example, the temperature measurement error is about 3.3 ° C.

  Thereby, in the temperature measurement at a high temperature (particularly 1200 ° C. or more), the thermocouple has a smaller temperature measurement error than the radiation thermometer, and can be measured more accurately. Therefore, in the heat treatment step (substrate treatment step) that is during high-temperature treatment, more accurate temperature control can be performed by controlling the temperature in the reaction tube based on the temperature detected by the thermocouple.

  Another difference in the characteristics between the thermocouple and the radiation thermometer is the difference in life. Thermocouples must be replaced in a certain period because temperature drift occurs when they are used for a long time in a high temperature state. On the other hand, the radiation thermometer has no problem such as temperature drift and has a long life. Moreover, in the temperature correction method of a radiation thermometer, it is only necessary to input a numerical value such as a reflectance of a measurement object (such as a reaction tube) to the temperature controller, so that it can be easily set.

  From the above, at least in the heat treatment step (substrate treatment step) during high temperature treatment, the temperature in the reaction tube is controlled based on the temperature detected by the thermocouple as the first temperature measuring means, In the forced cooling step, the temperature in the reaction tube is controlled based on the temperature detected by the radiation thermometer as the second temperature measuring means, so that the temperature can be controlled with good responsiveness and accuracy.

  In the description of the above embodiment, a batch-type apparatus that heat-treats a plurality of substrates is used as the heat treatment apparatus, but the present invention is not limited to this, and a single-wafer type may be used.

  The present invention can be applied to one process of manufacturing a SIMOX (Separation by Implanted Oxygen) wafer which is a kind of SOI (Silicon On Insulator) wafer.

  That is, in SIMOX, oxygen ions are first implanted into a single crystal silicon wafer by an ion implantation apparatus or the like. Thereafter, the wafer into which oxygen ions are implanted is annealed at a high temperature of 1300 ° C. to 1400 ° C., for example, 1350 ° C. or higher, for example, in an Ar, O 2 atmosphere using the heat treatment apparatus of the above embodiment. By these processes, a SIMOX wafer in which the SiO 2 layer is formed inside the wafer (the SiO 2 layer is embedded) is produced.

  In addition to the SIMOX wafer, the present invention can be applied to one step of the manufacturing process of the hydrogen anneal wafer.

  Even in the case of performing a high-temperature annealing treatment as one step of the substrate manufacturing process as described above, by using the present invention, it is possible to perform temperature control with good responsiveness and accuracy.

The present invention can also be applied to a semiconductor device manufacturing process.
In particular, a heat treatment process performed at a relatively high temperature, for example, an oxidation process such as wet oxidation, dry oxidation, hydrogen combustion oxidation (pyrogenic oxidation), HCl oxidation, boron (B), phosphorus (P), arsenic (As) It is preferably applied to a thermal diffusion process or the like in which impurities (dopants) such as antimony (Sb) are diffused into the semiconductor thin film.
Even in the case of performing the heat treatment step as one step of the manufacturing process of such a semiconductor device, by using the present invention, it is possible to perform temperature control with good responsiveness and accuracy.

It is a perspective view which shows the heat processing apparatus which concerns on embodiment of this invention. It is sectional drawing which shows the reaction furnace which concerns on embodiment of this invention. FIG. 3A shows an example of a temperature control pattern according to an embodiment of the present invention, FIG. 3A shows an example of a temperature sequence, FIG. 3B shows an example of temperature measuring means used in each sequence of FIG. c) shows each process corresponding to each sequence of Fig.3 (a). FIG. 4 (a) is a graph showing the responsiveness of a thermocouple and a radiation thermometer, and FIG. 4 (b) is an enlarged view of part of FIG. 4 (a). It is a graph.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Heat processing apparatus 40 Reaction furnace 42 Reaction tube 46 Heater 70 Cooling air 72 Cooling air channel | path 74 Supply pipe 76 Exhaust port 78 Exhaust path 80 Blower 82 Thermocouple 84 Radiation thermometer 86 Control apparatus

Claims (2)

A reaction tube;
A heater provided around the reaction tube for heating the substrate;
A cooling air passage formed between the reaction tube and the heater;
An air supply pipe for supplying a cooling gas to the cooling air passage;
An exhaust port for discharging the cooling gas from the cooling air passage;
Contact temperature measuring means provided in the cooling air passage ;
Non-contact temperature measuring means provided in the cooling air passage ;
When processing the substrate in the reaction tube, temperature control in the reaction tube is performed based on at least the temperature detected by the contact temperature measurement means, and when the reaction tube is rapidly forcedly cooled, at least the non-contact temperature measurement Control means for controlling the temperature in the reaction tube based on the temperature detected by the means;
The heat processing apparatus characterized by having. Carrying the substrate into the reaction tube;
Raising the temperature in the reaction tube to a processing temperature;
Processing the substrate at a processing temperature in the reaction tube;
A cooling air passage formed outside the reaction tube and configured to supply a cooling gas and having an exhaust port for exhausting the gas includes a step of rapidly forcibly cooling the reaction tube, and the temperature in the reaction tube Lowering the temperature from the processing temperature to a temperature lower than the processing temperature,
And a step of unloading the processed substrate from the processing chamber,
In the substrate processing step, temperature control inside the reaction tube is performed based on a temperature detected at least outside the reaction tube and by a contact temperature measuring means provided in the cooling air passage, and forced cooling in the temperature lowering step is performed. In the process, the temperature in the reaction tube is controlled based on the temperature detected at least outside the reaction tube and by a non-contact temperature measuring means provided in the cooling air passage .

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