JP4564081B2 - Heating apparatus, substrate processing apparatus, and semiconductor device manufacturing method - Google Patents

Description

  The present invention relates to a semiconductor manufacturing technique, and more particularly, to a heat treatment technique for performing processing in a state where a substrate to be processed is accommodated in a processing chamber and heated by a heating element, and relates to a heating apparatus, a substrate processing apparatus, and a semiconductor device manufacturing method.

  FIG. 1 shows a schematic cross-sectional view of a processing furnace 500 using a conventional heating apparatus. The heating device includes a metal casing 501 having a substantially cylindrical shape with an upper end covered, a substantially cylindrical heat insulating material 502 provided inside the casing 501, and a heating wire provided on the inner wall of the heat insulating material 502. 503. A soaking tube 504 and a reaction tube 505 forming a processing chamber are provided inside the heating device, and a desired heat treatment is performed on the wafer 506 in the reaction tube 505.

  In recent years, in the metal wiring process (Cu annealing or the like), a reduction in process temperature (300 ° C. or less) and further improvement in throughput are required. Therefore, it is important to shorten the temperature raising / lowering time of the wafer. However, if the heating device as shown in FIG. 1 responds to such a request, the current heater has a large-capacity heat insulating material so that it can be used in the middle and high temperature range, so the temperature rise / fall characteristics are poor and the throughput is improved. It was difficult. Therefore, there is a need for a highly responsive heating device with a small heat capacity.

  Further, in the substrate processing apparatus according to Patent Document 1, rapid cooling is enabled by passing a plurality of pins through a heating element and feeding a cooling gas from the pins into the heating space. And the responsiveness of a heating apparatus is improved by paying attention to a cooling characteristic.

  In recent years, with the miniaturization of wafer processing, it is necessary to further reduce the in-plane deviation (temperature deviation, film thickness deviation, etc. in the wafer plane) of the wafer. Therefore, in Patent Document 2, an in-plane deviation is reduced by providing a reflecting mirror at the upper end of the processing chamber and condensing the radiant heat rays of the peripheral heater at the center of the wafer.

  However, the attitude of the reflecting mirror is fixed, and the temperature adjustment at the center of the wafer cannot be adjusted independently from the peripheral portion of the wafer, and the problem of in-plane deviation has not been solved.

  In the heat treatment apparatus according to Patent Literature 3, a reflector that reflects the radiant heat from the heater provided at the peripheral edge of the substrate toward the substrate is movably provided above the substrate. However, the reflector is merely moved up and down with respect to the substrate to adjust the heat treatment temperature, and does not solve the problem of in-plane deviation.

  In the heat treatment apparatus described in Patent Document 4, an ultraviolet lamp is installed at a position facing the substrate, and a plurality of reflectors are provided between the substrate and the lamp so that the reflector can be moved or the angle of the reflecting surface can be changed. Are uniformly irradiated. However, there is no disclosure or suggestion regarding in-plane deviation.

In addition, in the heat treatment apparatus described in Patent Document 5, a temperature sensor capable of measuring the temperatures of the peripheral portion of the uppermost substrate and the central portion of the substrate is provided, and a plurality of heating means are controlled at different positions based on information of the temperature sensor. is doing. However, the control of the plurality of heating means is complicated, and the in-plane deviation has not been sufficiently eliminated.
WO2007 / 023855 JP 2005-32883 A JP 7-321059 A JP 2006-114848 A JP 2004-119510 A

  In view of such a conventional situation, an object of the present invention is to further reduce an in-plane deviation of a substrate to be processed.

  In order to achieve the above object, a heating device according to the present invention includes a wall body surrounding a heating space, a heating element disposed in a cylindrical shape inside the wall body, and a cylindrical end portion of the heating element. A plurality of reflectors that are arranged so as to cover from the center of the space to the peripheral edge of the heating space, and that reflect the heat rays from the heating element, and at one end located at the center of each of the plurality of reflectors A movable part connected to move the plurality of reflectors, and connected to at least the other end side of each of the plurality of reflectors, and a plurality of parts that regulate the movement of the reflectors as support axes when the movable part operates. It has a support shaft body.

  According to the feature of the substrate processing apparatus according to the present invention, since the reflection state is changed by the moving mechanism based on the in-plane deviation, the in-plane deviation of the substrate can be further reduced.

  Other objects, configurations, and effects of the present invention will become apparent from the following embodiments of the present invention.

Next, the present invention will be described in more detail with reference to the accompanying drawings as appropriate.
Hereinafter, a first embodiment as the best mode for carrying out the present invention will be described with reference to the drawings.

  As shown in FIGS. 2 to 7, the substrate processing apparatus 1 generally includes a reaction vessel 309 that forms a processing chamber 308, a heating device 3 disposed on the outer periphery of the reaction vessel, and a main controller 4. Yes.

  The heating device 3 generally includes a ceiling portion 10, a cylindrical intermediate portion 11, a lower portion 12, and a terminal case 13, and a heating element 20 is supported on the intermediate portion 11. The ceiling portion 10 is formed with an elbow-shaped exhaust conduit 81 that opens to the lower surface and the side surface, and further includes a reflection device 90 at the lower portion thereof. The intermediate portion 11 surrounds the inner shell 50 that supports the heating element 20 with the outer shell 60 in an insulated state, and further surrounds the outer periphery with a decorative panel 70. The inner shell 50 and the outer shell 60 are made of a conductive material, for example, a metal material such as a stainless steel material.

  A cooling gas introduction duct 7y is attached between the upper part of the intermediate part 11 and the intake attachment 7x. For example, a butterfly valve is attached as an opening / closing valve 7a to the opening of the intake attachment 7x so that the flow path can be opened and closed. The intake attachment 7 x is connected to the cooling gas supply line 7. An air passage 14 is formed between the inner shell 50 and the outer shell 60 as a cylindrical cooling medium circulation passage. The cooling gas introduction duct 7y communicates with the airway 14 by a plurality of pipes 61 that are arranged substantially equally in an annular shape. On the other hand, a forced exhaust line 8 having an exhaust blower 8 a that performs forced exhaust is connected to the exhaust conduit 81, and forced exhaust of a heating space that is an internal space of the heating device 3 is performed. A gas such as air or an inert gas introduced from the cooling gas supply line 7 is supplied as a cooling gas to the heating space 18 from the airway 14 and a plurality of insulator holes described later, and is exhausted from the forced exhaust line 8.

  The reaction vessel 309 includes a soaking tube 315 and a reaction tube 310 that are sequentially arranged concentrically in the heating space 18, and a processing chamber 308 is formed in the reaction tube 310. The processing chamber 308 stores a boat 300 that holds wafers 305 in multiple horizontal stages. The boat 300 can be loaded into and pulled out from the processing chamber 308 by a boat elevator (not shown).

  In the reaction tube 310, a reaction gas introduction tube 5x and an exhaust tube 6x are communicated. The reaction gas introduction pipe 5x is provided with a flow rate controller 5a, and the exhaust pipe 6x is provided with a pressure controller 6a. The reaction gas is introduced at a predetermined flow rate, and the internal gas is exhausted from the exhaust port 6y so that the inside of the reaction tube 310 is maintained at a predetermined pressure, and is discharged out of the processing chamber through the exhaust pipe 6x.

  The other cooling gas supply line 5 y is communicated with a soaking tube inner space 317 formed between the soaking tube 315 and the reaction tube 310. The cooling gas supply line 5y is provided with a flow rate controller 5b. The intake attachment 7x is provided with an open / close valve 7a. The forced exhaust line 8 is provided with an exhaust blower 8a as an exhaust device. That is, it is possible to introduce and adjust the cooling gas as appropriate to both the soaking tube inner space 317 and the heating space 18.

  The heating element 20 is divided into a plurality of zones Z1 to Z5 as required with respect to the axial direction of the cylinder of the intermediate portion 11, and zone control is possible. Each zone is provided with a temperature detector that detects the heating temperature of each zone. Note that the heating element 20 may have the same calorific value in each zone by making the molding pattern of each zone the same.

  Each part of the substrate processing apparatus 1 is controlled by the main controller 4. For example, the processing state of the wafer 305 processed in the reaction tube 310 is controlled by the main controller 4. The main controller 4 includes a temperature monitor 4a, a heating controller (heating controller) 4b, a reflection controller 4c, a first flow controller 4d, a pressure controller 4e that controls the pressure in the reaction tube 310, and a second A flow control unit 4f, an exhaust control unit 4g, and a drive control unit 4h for controlling mechanical units such as the boat elevator are provided.

  The temperature monitor unit 4a detects the temperatures of the first to third temperature detectors TC1 to TC3. Here, the first temperature detector TC1 is provided for each of the zones Z1 to Z5 in the vicinity of the heating element 20. The second temperature detector TC <b> 2 is provided for each of the zones Z <b> 1 to Z <b> 5 in the peripheral portion in the reaction tube 310. Further, the third temperature detector TC3 is provided above the reaction tube 310 or in a range including the upper center of the reaction tube 310.

  The heating control unit 4b controls the amount of heat generated by the heating elements 20 in the zones Z1 to Z5 based on the detection result of the temperature monitoring unit 4a. Further, the reflection control unit 4c controls the actuator 99 as a driving device of the reflection device 90 based on the detection result of the temperature monitor unit 4a. Then, the reflector (reflector) 91 having a mirror-finished lower surface is appropriately tilted to change the light collection degree from the heating element 20 to the upper center of the reaction tube 310, and the temperature of the same part is controlled.

  The first flow rate control unit 4d controls the flow rate controller 5a, and the pressure control unit 4e controls the pressure controller 6a to control the introduction of the reaction gas and the pressure. The second flow rate control unit 4f controls the flow rate controller 5b, and the exhaust control unit 4g controls the opening / closing valve 7a and the exhaust blower 8a to control introduction and discharge of the cooling gas.

  FIG. 4 shows an enlarged view of portion A in FIG. The heating element (heater wire) 20 is fixed to the inner shell 50 by a hanging insulator 30 as an insulating material such as alumina. The heating element 20 is made of a heat-generating material that can be rapidly heated, such as an Fe-Al-Cr alloy, and has a cross-sectional shape such as a flat plate so as to increase the heat-generating surface area. It is configured. The heating element 20 has meandering folded portions 21 and 22 above and below, and an intermediate portion includes a strand portion 23 that connects the upper folded portion 21 and the lower folded portion 22 with a half-pitch shift, and each strand. The gap 24 is located between the portions 23. The upper portion of the heating element 20 is bent as a bent portion 20 a held by the hanging insulator 30. The inner surface of the inner shell 50 is mirror-finished, and heat rays radiated from the rear surface of the wire portion 23 of the heating element are reflected by the inner surface and radiated from the gap 24 toward the heating space 18.

  The hanging insulator 30 as an insulating material includes an upper insulator 31 and a lower insulator 32 made of a heat-resistant insulating material such as alumina, and the pin 35 is sandwiched between the upper metal member 33 and the lower metal member 34 with the bent portion 20a at the upper part of the heating element 20 interposed therebetween. It is fixed by welding. The lower metal fitting 34 is attached to the inner shell 50 by bolts 36 at two bent portions.

  The inner shell 50 has a through hole 40a in the center, and a plurality of quench pipes 40 for supplying the cooling gas in the air passage 14 into the inner shell 50 protrude from the inner wall of the inner shell 50 toward the heating space 18 side. Is provided. The quench pipe 40 is made of an insulating heat resistant material such as alumina. The quenching pipe 40 includes a through portion 40d that penetrates the heating element 20 in the gap 24, and a protruding portion that protrudes from the through portion 40d in a direction that intersects the penetration direction V in which the penetration portion 40d penetrates the heating element 20. The movement of the middle of the heating element 20 is limited by the substantially circular ridges 40b and 40c. That is, a groove is formed in the through portion 40d between the pair of flanges 40b and 40c. Further, the lower end of the heating element 20 is provided at a position overlapping the upper end position of the lower hanging insulator 30 to restrict the movement of the lower end of the heating element 20 in the protruding direction of the quench pipe 40.

  On the back surface of the inner shell 50, a water cooling pipe 59 as a cooling medium circulation passage is provided. The water-cooled tube 59 is wound around the outer surface of the inner shell 50 in a spiral manner in the axial direction and welded. For example, by flowing a cooling medium such as cooling water through the supply / drainage paths 59a and 59b, the temperature of the inner shell 50 is prevented from rising and kept almost constant.

  The outer shell 60 is attached to the outside of the inner shell 50 in an insulated state via a plurality of connecting insulators 51. Since the connecting insulator 51 is made of an alumina material having insulation and heat resistance, even if the heating element 20 and the inner shell 50 are unexpectedly brought into contact with each other and a current is transmitted to the inner shell 50, for example, the connection insulator 51 is connected. The insulator 51 does not transmit current to the outer shell 60.

  The inner side of the connecting insulator 51 is fixed to the inner shell 50 with a first bolt 52. On the other hand, the outer side of the connecting insulator 51 is fixed to the outer shell 60 with a second bolt 54 via an annular hollow collar 53 as an insulating heat resistant material. The collar 53 is provided through the mounting hole of the outer shell, is formed thicker than the thickness of the outer shell 60, and provides a clearance (gap) between the lower surface of the head of the second bolt 54 and the outer surface of the connecting insulator 51. Yes. Even if the inner shell 50 swells due to thermal expansion, the amount of deformation is absorbed by this clearance to prevent thermal stress from acting on the outer shell 60 and to prevent deformation of the outer shell 60.

  On the outer side of the outer shell 60, a decorative panel 70 is provided as a side wall outer layer which is an outermost shell through a column 62. The decorative panel 70 is provided with an opening 61a communicating with the cylindrical airway 14 at the upper part of the outer shell 60 through a pillar 62 having a flange, for example, by a metal rivet 62a. One end of the pipe 61 is welded to 61a. The pipe 61 penetrates the decorative panel 70, and the other end communicates with the cooling gas introduction duct 7y. In addition, the pillar 62 and the decorative panel 70 are comprised from the material which has electroconductivity, for example, is comprised from metal materials, such as stainless steel material. For this reason, the decorative panel 70 and the outer shell 60 are connected in a conductive state via the pillar 62. In addition, by preventing the conduction to the outer shell 60 and the decorative panel 70 as described above, the conduction to the entire substrate processing apparatus is prevented, and an electric shock at the time of work and the electrical components in the substrate processing apparatus are prevented from being damaged.

  As shown in FIG. 4, the inner shell 50 is divided into a plurality of parts in the vertical direction. A gap 50 s is provided between the divided upper shell and the lower shell adjacent thereto. And between the 1st flange 50t provided in the upper shell which is an upper shell among the inner shells 50, and the water cooling pipe 59 of a lower shell, the heat insulation blanket 50a which consists of heat insulation members, such as a ceramic fiber, is interposed, and gap The heat escape from 50s is prevented, and the upper and lower shells are thermally divided.

  As shown in FIG. 7, at the lower part of the intermediate part 11, a heat insulation and a heat insulation blanket as an insulation member are provided between the second flange 50 x projecting outside the inner shell 50 and the third flange 60 x projecting inside the outer shell 60. 50y is interposed. Thereby, the inner shell 50 and the outer shell 60 are insulated from each other and kept airtight by the heat insulating blanket 50y. Further, a heat insulating blanket 60y as a heat insulating member is provided between the third flange 60x and the bottom lid 72a to keep the inner shell 50 internal space airtight. A structure having the same concept is also adopted between the intermediate portion 11 and the ceiling portion 10 to maintain an insulating state and an airtight state. The lower part of the lowermost heating element 20 is supported by a quenching pipe 42 provided separately from the quenching pipe 40 that restricts the movement of the middle of the heating element 20.

  In recent years, miniaturization of wafer processing has progressed, and it has become necessary to further reduce the in-plane deviation of the wafer. In particular, the temperature of the wafer 305 located at the upper part of the boat 300 is likely to be lower than that of the peripheral edge due to heat radiation from the ceiling unit 10. In this case, uniform heat treatment cannot be performed at the center and the periphery of the wafer. Further, in the CVD process, since the processing gas is supplied from the peripheral part of the boat, the processing gas concentration at the central part of the boat is lowered, and the film thickness at the central part of the wafer is further reduced compared to the peripheral part. It was.

  For this reason, in the CVD process, there has been a demand to increase the temperature at the center of the wafer as compared with the peripheral part in order to compensate for the decrease in the reaction rate accompanying the decrease in the processing gas concentration. In order to solve this problem, the reflector is fixedly provided as in the above prior art, the heat rays of the peripheral heating element are concentrated on the center of the boat, and the amount of heating at the center of the wafer is increased. A method of adjusting the in-plane temperature deviation is also conceivable.

  However, since the heater output differs between when the heater is warmed up and when it is stable, the wafer in-plane deviation cannot be controlled properly with a single reflector angle. When the temperature is raised, a larger output is obtained than when the temperature is stable. Therefore, when the angle of the reflector is adjusted in a stable state, the central portion becomes hotter than the peripheral portion when the temperature is raised. On the contrary, when the angle of the reflector is adjusted in the state of increasing the temperature, the central portion becomes cooler than the peripheral portion when stable (annealing process, film forming process).

  Some process sequences start wafer processing from the end of the temperature rise to reduce process time. Therefore, it is necessary to control the in-plane deviation of the wafer as needed.

  As shown in FIGS. 8 and 9, the reflection device 90 of the present invention in the ceiling portion 10 adjusts the angle of the reflector 91 by moving the reflector 91 by the moving mechanism 92 according to the wafer surface temperature. Reduce in-wafer deviation.

  The ceiling unit 10 has an exhaust conduit 81 for exhausting the atmosphere of the heating space 18. Similarly to the structure of the lower part 12, the ceiling unit 10 also has a structure that absorbs expansion and contraction of the inner shell 50 while ensuring insulation and airtightness with the inner shell 50 by combining a flange and a heat insulating cushion (heat insulating blanket). It is as.

  A reflection device 90 that reflects heat rays (light) radiated from the heating element 20 is provided below the ceiling unit 10. The reflection device 90 performs temperature control by tilting a plurality of curved plate-like reflectors (reflectors) 91 that reflect heat rays by a moving mechanism 92 and an actuator 99 and changing the reflection direction.

  The reflector 91 has a triangular shape when viewed from the bottom, has a substantially arc shape when viewed from the side, and is curved with a size exceeding the peripheral edge from the center of the wafer 305 as shown in FIGS. That is, the reflector 91 is provided so as to cover from the center of the heating space 18 to the vicinity of the peripheral edge of the heating space 18. Preferably, as shown in FIGS. 8 and 9, the wafer 305 may be curved so as to protrude toward the ceiling wall body with a size exceeding the peripheral edge from the center. Thereby, it can utilize for reflection of a heat ray in the substantially whole surface between the front-end | tip part and peripheral part of the reflector 91, it becomes possible to increase the reflective effect of a heat ray and to improve the condensing state of a heat ray. . And the heat insulation effect of the ceiling part 10 can also be improved according to the reflective effect of a heat ray. Preferably, the reflector 91 is extended from the central portion of the wafer 305 to a vertical position perpendicular to the circumferential position where the heating element 20 is held. By comprising in this way, a reflective surface increases, a reflection effect can be increased further, the condensing state of a heat ray can be improved, and also the heat insulation effect of the ceiling part 10 can be improved.

  The plurality of reflectors 91 are annularly arranged with a gap 91a therebetween. As described above, since the reflector 91 is formed in a triangular shape (fan shape), the plurality of reflectors 91 can be easily arranged in an annular shape. Preferably, the plurality of reflectors 91 are formed in the same shape and are substantially equally arranged in the circumferential direction. Thereby, the flow of the exhaust gas from the heating space 18 can be evenly divided in the circumferential direction by the gap 91a, and the temperature difference in the wafer surface in the circumferential direction can be reduced. Preferably, if the circumferential width of the gap 91a is also equal, the exhaust flow can be more evenly divided in the circumferential direction, and the temperature difference in the wafer surface can be reduced. .

  The moving mechanism 92 supports a vertex that is one end side of each reflector 91 on a central plate 94 that is supported by a shaft 93 as a movable portion so as to be vertically movable, and a peripheral portion that is the other end side of each reflector 91. Is supported by two bolts 95 as a support shaft body. This makes it possible to simultaneously adjust the angles of the plurality of reflectors 91 arranged in an annular shape by the shaft 93, and to make a uniform reflection state in the circumferential direction of the heating space 18 no matter which angle is adjusted. it can. In addition, the angle adjustment may be performed by driving the shaft 93, and the structure of the moving mechanism 92 is simplified. Further, the heat rays can be reflected point-symmetrically with respect to the wafer 305 around the shaft 93, and the entire wafer can be heated uniformly.

  The actuator 99 can control the reflection state by the reflector 91 by moving the shaft 93 up and down based on the signal from the reflection control unit 4 c and adjusting the angle of the reflector 91 at the position of the shaft 93. Preferably, the center plate 94 to which one end of the plurality of reflectors 91 is connected can be positioned vertically lower than the bolt 95 to which the other end side of the plurality of reflectors 91 is connected when moved downward. It is good to provide it. Thereby, since the ceiling part 10 does not need to be enlarged in the vertical direction, it is not necessary to increase the vertical size of the substrate processing apparatus in the heating apparatus.

  The atmosphere in the heating space 18 is sucked from the four first openings 82 that are equally distributed around the heater via the gap 91a or the periphery of the reflector 91. Then, after being gathered together by the second opening 83 on the central axis of the heater, it is discharged to the outside of the heating device 3 through the exhaust port 81a. Preferably, the width of the gap 91a is smaller than the diameter of the opening surface of the first opening 82, that is, the gap 91 is narrower. Thereby, as shown in FIG. 9, even if the 1st opening 82 is a location provided facing a part of above-mentioned several clearance gap 91a, it suppresses the exhaust_gas | exhaustion amount from the clearance gap 91a. The flow of exhaust from the heating space 18 can be evenly divided in the circumferential direction.

  The reaction vessel 309 is provided with a soaking tube 315 made of SiC or quartz material, and a reaction tube 310 as a reaction vessel made of SiC or quartz material. A wafer 305 serving as a substrate placed on a boat 300 serving as a substrate holder is disposed in the reaction tube 310.

  A temperature sensor 330 as the second temperature detector TC2 is installed at the peripheral edge in the reaction tube 310, and a thermocouple contact as a temperature detector is installed for each of the zones Z1 to Z5. In the reaction tube 310, an L-type temperature sensor 320 is installed as the third temperature detector TC3 whose tip is bent into an L shape. The L-type temperature sensor 320 is bent in an L shape above the boat 300 in the reaction tube 310. In the L-type temperature sensor 320, a thermocouple contact 321 as a temperature detector is disposed at a portion located at the center of the wafer (boat top plate), and a thermocouple contact 322 as a temperature detector is provided at a portion located at the periphery. Thus, the temperature of the center portion and the peripheral portion of the wafer (boat top plate) can be detected.

  Based on the temperature detected by the temperature sensor 330, the heating element controller 4b controls the heating element output for each zone. Moreover, the temperature data of the center part and the peripheral part detected by the L-type temperature sensor 320 are transmitted to the temperature monitor unit 4a. The reflection control unit (control device) 4c calculates the current in-plane deviation (temperature deviation) of the wafer from the temperature data of the central part and the peripheral part, and causes the actuator 99 to respond to the difference from the in-plane deviation of the target value. A signal is sent, the shaft 93 is operated, the angle of the reflector 91 is changed, and feedback control is performed. Preferably, when the deviation between the temperature of the center portion and the peripheral portion detected by the L-type temperature sensor 320 is larger than the preset allowable range of the in-plane deviation, the shaft 93 is set so as to reduce the in-plane deviation. It is preferable to change the angle of the reflector 91 by operating and to perform feedback control. Thereby, the condensing state to the center part of the wafer can be automatically changed, and the in-plane deviation of the wafer can be optimally controlled.

Next, the operation of the substrate processing apparatus 1 will be described.
In the processing of the wafer 305, the boat 300 loaded with the wafer 305 is loaded into the reaction tube 310 by a boat elevator and rapidly heated to a predetermined temperature by the heating device 3. While the wafer 305 is heated to a predetermined temperature by the heating device 3, the reaction gas is introduced from the reaction gas introduction pipe 5 x, the exhaust gas is discharged through the exhaust pipe 6 x, and a necessary heat treatment is performed on the wafer 305. Made.

  Usually, the temperature of the boat 300 is kept at a required temperature, for example, 550 ° C. before the boat 300 is charged. After the boat 300 is charged, the temperature is raised to a wafer processing temperature, for example, 850 ° C. In addition, the temperature before loading and the processing temperature are appropriately selected according to the processing content in the substrate processing apparatus.

  The heating element 20 at each stage of the heating element 20 is measured for each independent zone by the temperature monitor unit 4a, and the temperature is controlled by the heating element 20 and the reflection device 90. Since the heating element 20 in each zone is one continuous heating element, if there is an abnormality in the heating element 20, for example, if there is a disconnection, it can be detected immediately, and the deterioration state of the heating element in each stage can be easily found. I can grasp it.

  When the process is complete, it is rapidly cooled to the wafer exit temperature, eg, 550 ° C. For the cooling after the processing of the wafer 305, the flow rate controller 5a and the air valve 7a are opened, and an inert gas such as air or nitrogen gas is supplied from the cooling gas supply lines 5y and 7 as a cooling gas. The cooling gas supplied from the cooling gas supply line flows into the heating space 18 through the through hole 40a of the quenching pipe 40, and cools the heating element 20 from both the outer surface and the inner surface.

  In such a configuration using the cooling pipe 40, the cooling rate of the heater, and thus the cooling rate of the wafer can be improved, and the throughput of the wafer processing can be improved. Further, since the cooling pipe 40 serves as both a heating element presser and a cooling gas supply pipe, it is not necessary to provide a separate gas pipe for cooling the heater, so that the area of the heating element on the inner wall of the heater can be improved. Furthermore, since the opening part of the through-hole 40a of the cooling pipe 40 is opened inside the heat generating body 20, the heat generating body 20 is prevented from being locally cooled by the cooling gas. As a result, local deformation, twisting, and cracking of the heating element 20 can be suppressed, and further, disconnection of the heating element 20 and contact with the reaction tube 310 can be prevented.

  The cooling gas introduced into the cylindrical air passage 14 is dispersed through the cooling gas introduction duct 7y having a large volume, so that the cooling gas uniformly flows into the air passage 14 and the occurrence of uneven cooling is prevented. Thereafter, the cooling gas is blown into the heating space 18 through the plurality of pipes 61, the airway 14, and the plurality of quenching pipes 40, and rises in the heating space 18 and is exhausted from the exhaust conduit 81. The inner surface of the inner shell 50 is cooled by the cooling gas rising in the heating space 18, and the soaking tube 315 and the reaction tube 310 are rapidly cooled by the cooling gas rising in the heating space 18 and the soaking tube inner space 317. As a result, the wafer 305 in the reaction tube 310 is rapidly cooled. By adopting a heating element such as Fe—Cr—Al, carbon, or SiC as the heating element 20, rapid heating and high temperature heating are possible, and further rapid cooling is possible by cooling the heating device 3 with a cooling gas. .

  When the cooling is completed, the boat 300 is lowered by the boat elevator, and the processed wafer 305 is discharged from the boat 300. In the case of the decompression process, the boat 300 is lowered after returning the reaction chamber to atmospheric pressure.

This specification includes the following inventions.
1) The control device detects a temperature of a peripheral portion (periphery) of a substrate in the reaction vessel, and a second temperature detector detects a temperature of a central portion (center) of the substrate in the reaction vessel. A substrate processing apparatus for obtaining a temperature deviation between a peripheral portion and a central portion of the substrate based on a detection result of the temperature detecting body and controlling the moving mechanism based on the obtained temperature deviation.

  2) The said substrate processing apparatus with which the said reflector is provided in the upper part in this heating apparatus.

  3) A substrate carrying-in step for carrying a substrate into the reaction vessel, a substrate processing step for treating the substrate by heating the inside of the reaction vessel with a heating device, and a substrate carrying-out step for carrying the substrate out of the reaction vessel. In the substrate processing step, the control device controls the moving mechanism based on the in-plane deviation between the peripheral edge portion and the central portion of the substrate, and moves the reflector that reflects the heat rays in the reaction vessel to reflect the heat rays. For manufacturing a semiconductor device.

  4) In the substrate processing step, the control device detects a temperature of a peripheral portion of the substrate in the reaction vessel and a temperature of a central portion of the substrate in the reaction vessel. A method of manufacturing a semiconductor device, wherein a temperature deviation between a peripheral portion and a center portion of the substrate is obtained based on a detection result of the temperature detector, and the moving mechanism is controlled based on the obtained temperature deviation.

  5) A side wall formed in a cylindrical shape and a plate-like heating element having a plurality of gaps, the inner surface of the side wall being finished so as to be able to reflect heat rays, and the heating element is arranged along the cylindrical inner surface of the side wall The heating element surface of the heating element radiates heat rays toward the heating space, and the heat ray radiated from the back surface of the heating element part is reflected by the inner surface and passes through the gap to be radiated to the heating space. Apparatus, substrate processing apparatus, and heating element holding structure. In this structure, the width of the gap 24 is sufficiently larger than the width of the strand portion 23, so that the heat rays reflected from the inner surface can be effectively used. If a gap is formed along the cylindrical central axis and the upper side of the central axis is supported by the holding member, the radiant heat can be effectively used and the surface density of the heating element can be improved. It is possible to improve the thermal responsiveness. Further, by making the cylindrical inner surface a concave curved surface, it is possible to improve the efficiency with which the reflected heat rays are radiated into the heating space through the gap, and it is desirable that the concave curved surface is an arc surface. .

  The present invention is not limited to the above embodiment, and various modifications can be made without departing from the scope of the invention.

  In the above embodiment, the reflector is controlled by calculating the in-plane deviation of the wafer using the temperature data of the center part and the peripheral part detected by the L-type temperature sensor 320, and the difference from the in-plane deviation of the target value. Accordingly, feedback control for changing the angle of the reflector 91 is performed. However, the control of the reflector is not limited to feedback control, and can be controlled by a program.

  Wafer processing (temperature increase / decrease, gas control, etc.) is controlled by a program called a recipe. This recipe includes a plurality of events such as temperature rise, stability, and temperature drop, and each event is composed of process conditions such as “execution time”, “heater temperature”, “valve opening / closing time”, and “gas flow rate”. “Reflector angle information” for adjusting the angle of the reflector may be added to the process conditions to perform program control. For example, the reflector angle is set to “A state during a temperature rising event” and the reflector angle is set to “B state” during a stable (processing, film formation) event.

  As described above, the heater output is different between when the temperature of the heater is raised and when it is stable, and when the temperature is raised, a larger output is required than when it is stable in order to heat the entire wafer uniformly and quickly. When the temperature is stable, the output is smaller than when the temperature is raised, and the temperature of the wafer central portion is likely to be lower than the peripheral portion of the wafer due to the exhaust duct 81 of the ceiling portion 10, and in-plane deviation of the wafer is likely to occur. Therefore, at the temperature rising event, as shown in FIG. 10, the shaft 93 is set to an angle at which the entire wafer is heated quickly, and the entire wafer is heated uniformly. On the other hand, at a stable event, as shown in FIG. 11, the angle is set so that the heat rays are concentrated at the center of the wafer. Since the amount of heat radiation is large at the time of temperature rise, even if the radiant heat is dispersed, an in-plane deviation at the center of the wafer is less likely to occur, and the heating rate is accelerated by heating the entire wafer. On the other hand, since the amount of heat radiation is small when stable, the radiant heat is concentrated on the center of the wafer to make in-plane deviation difficult to occur. Thus, the in-plane deviation can be reduced by setting the reflector angle according to the event.

  In addition, in the event, the reflector angle is not limited to the state of 1, but can be set to have a plurality of states. For example, in the first half of the temperature rising event, as shown in FIG. 10, the angle is set to disperse the radiant heat so as to heat the entire wafer widely and uniformly. In the latter half, as shown in FIG. 11, the angle is set so that light is condensed near the center of the wafer. Thus, more precise angle adjustment is possible.

  Such angle condition setting may be performed using the L-type temperature sensor 320 at the initial stage of operation of the substrate processing apparatus (when starting up) before processing the product wafer or after maintenance (immediately after) of the substrate processing apparatus. Good. Alternatively, a film forming (annealing) test may be performed on the test wafer, and the angle condition may be set based on the film forming condition (annealing condition). Although the temperature rising event has been described as an example, the event may be set as described above according to each event even when the temperature is stable or when the temperature falls.

  In the above embodiment, the thermocouple contact (contact 321 and contact 322) as two temperature detectors is used to calculate the wafer in-plane deviation, but the temperature detector can be variously modified. For example, a temperature detection body in the zone Z1 of the temperature sensor 330 and an L-type temperature sensor 320 (for example, including the contact 321) may be used. Further, the wafer in-plane deviation may be calculated using three or more temperature detectors.

  Further, in the above embodiment, the thermocouple contact for measuring the wafer surface is provided on the boat 300, but the position thereof can be variously modified. For example, a thermocouple contact may be attached to the top plate of the boat 300 or may be embedded in the top plate. Further, a thermocouple contact may be provided between the boat 300 and the wafer 305, or a thermocouple contact may be attached to the wafer.

  For example, the control device stores in advance the result of obtaining the film thickness deviation between the central part and the peripheral part in the wafer surface, and based on this film thickness deviation, the reflector is moved to adjust the heat ray reflection of the heating element. The moving mechanism may be controlled so as to adjust and eliminate the film thickness deviation. Preferably, as a result of film formation on the wafer in advance, the deviation of the film thickness between the central portion and the peripheral portion in the wafer surface is calculated, and if the deviation is larger than the preset allowable tolerance of the in-plane deviation, the inner surface deviation is calculated. It is preferable to operate the shaft 93 so as to make it smaller.

  In the above embodiment, the temperature sensors 320 and 330 are provided as the second and third temperature detectors TC2 and TC3. However, as the second and third temperature detectors TC2 and TC3, temperature sensors having independent thermocouple contacts as temperature detectors may be used.

  The temperature detector may be not only a thermocouple contact but also a radiation thermometer, and any type or configuration can be used as long as it can detect the temperature.

  The shape of the reflector 91 and the moving mechanism 92 can be variously modified. For example, the state of reflection by the reflector 91 can be changed by moving the peripheral side of the reflector 91 up and down or changing the horizontal position of the reflector 91. However, the above-described embodiment in which the center of the reflector 91 is moved along the axis of the intermediate portion 11 is simple in the mechanism, and is used for condensing the heat rays from the heating element 20 at the peripheral portion on the central portion of the wafer. It is excellent in that it can be used for reflection between the distal end portion and the peripheral portion of the reflector 91 and that reflection can be performed point-symmetrically around the shaft 93.

  As for the shape of the reflector, for example, as shown in FIG. 12, the reflector 91 'forms a flat surface and is bent to form a slope in part. Further, the bending is not limited to one place, and a plurality of bendings may be provided. It should be noted that the shape of the central plate that holds one end of the reflector can be modified in accordance with the shape of the reflector.

  The reflection device 90 may be provided at the cylindrical end of the heating element 20 arranged in a cylindrical shape, and may be provided at the lower portion as well as the upper portion of the heating device 3. However, the lower part needs to be opened in order to move the boat, and the upper part is provided with an exhaust port and the temperature is likely to decrease.

  Although the reaction vessel has been described as including both the soaking tube and the reaction tube, the reaction vessel may include only the reaction tube without including the soaking tube. In addition, you may be comprised not only in a double pipe but in the number of pipes of 1 pipe or a triple pipe or more.

  The heat treatment is not limited to oxidation treatment, diffusion treatment, and diffusion, but is not limited to reflow and annealing treatment for carrier activation and planarization after ion implantation, and may be heat treatment such as film formation treatment. The substrate is not limited to a wafer, but may be a photomask, a printed wiring board, a liquid crystal panel, an optical disk, a magnetic disk, or the like. The present invention is not limited to batch-type heat treatment apparatuses and single-wafer-type heat treatment apparatuses, and can be applied to all semiconductor manufacturing apparatuses provided with a heater unit. The inner shell 50 and the mirror finish portion of the reflector 91 may be mirror-finished by polishing stainless steel, or may be plated with a noble metal such as gold or platinum.

The embodiment of the present invention is configured as described above, but may be more comprehensively configured as described below.
The heating device according to the present invention includes a wall body that surrounds the heating space, a heating element that is arranged in a cylindrical shape inside the wall body, and a cylindrical end portion of the heating element that is heated from the center of the heating space. A plurality of reflectors arranged so as to cover the peripheral edge of the space and reflecting the heat rays from the heating elements, and the plurality of reflectors connected to one end located at the central portion of each of the plurality of reflectors And a plurality of support shaft bodies that are connected to at least the other end sides of the plurality of reflectors and restrict the movement of the reflectors as support shafts when the movable portion operates. In this case, the plurality of reflectors are arranged in an annular shape, and the movable portion is connected to the plurality of reflectors at the annular center, and the operation of the movable portion causes the support shaft body to serve as the support shaft. It is preferable that the plurality of reflectors be movable. One of the cylindrical end portions of the heating element may be located on a ceiling wall body side which is one of the wall bodies, and the plurality of reflectors may be arranged on the ceiling wall body side.
Further, a gap may be formed between the plurality of reflectors. The reflector may be formed in a triangular shape based on the annular center. The plurality of reflectors are substantially equally arranged in the circumferential direction. The plurality of reflectors may be curved so as to protrude toward the ceiling wall body.
The wall body is formed at least by a cylindrical side wall body and a ceiling wall body disposed on the upper end side of the side wall body, the heating element is held by the side wall body, and the movable portion is the ceiling wall body You may hold it. In this case, the ceiling wall body is provided with an opening communicating with the exhaust port for exhausting the inside of the heating space, and at least one of the gaps formed between the plurality of reflectors is the opening. It is good that it is narrower than the diameter of the opening surface. The wall body is provided with an exhaust port for exhausting the inside of the heating space, and the exhaust port communicates with a plurality of openings arranged in a circumferential direction around the movable portion, and the reflector Is formed in a triangular shape, and the plurality of reflectors are arranged annularly with the triangular base at the center, and at least one of the gaps is an opening surface of the opening. It is narrower than the diameter. It is preferable to provide a moving mechanism that changes the reflection state of the heat rays by changing the angles of the reflecting surfaces of the plurality of reflectors with respect to the heating element, with the supporting shaft body as a supporting shaft by the operation of the movable portion. The reflector may be formed to be curved with a size that covers from the center of the heating space to the vicinity of the peripheral edge of the heating space.
The plurality of reflectors may extend from the axial center position of the side wall body to a vertical position perpendicular to a circumferential position where the heating element is held. The reflector may be curved so that the ceiling wall side is convex.
In the substrate processing apparatus of the present invention, a reaction vessel for processing a substrate inside is provided in a heating space inside the heating apparatus of the above aspect. In this case, it may further comprise a control unit that operates the movable unit when a temperature or film thickness deviation between the peripheral part and the central part of the substrate is larger than a predetermined deviation, and the peripheral part of the substrate in the reaction vessel Based on the detection results of the first temperature detector that detects the temperature of the substrate and the second temperature detector that detects the temperature of the center of the substrate in the reaction vessel, the temperature of the peripheral edge and the center of the substrate A controller may be further provided that calculates a deviation and operates the movable part when the calculated temperature deviation is larger than a predetermined deviation. Further, it is desirable that the reflector is curved so as to have a size exceeding the peripheral portion of the substrate from the central portion of the substrate. Another aspect of the substrate processing apparatus of the present invention includes a reaction vessel that processes a substrate, and a heating device that is disposed on an outer periphery of the reaction vessel and heats the substrate in the reaction vessel. A heating element arranged in a cylindrical shape so as to surround the reaction vessel, and a size exceeding the peripheral edge of the reaction vessel from the center of the substrate in the reaction vessel, arranged at the cylindrical end of the heating element, A plurality of reflectors for reflecting the heat rays of the heating element, and a movement mechanism for moving the plurality of reflectors to change the reflection state of the heat rays, and a peripheral portion and a center portion of the substrate. A control unit that controls the moving mechanism based on an in-plane deviation, and the moving mechanism is connected to one end side of each of the plurality of reflectors and is movable to move the plurality of reflectors. And at least the plurality of reflectors that Is connected to the other end of the record is to have a plurality of support shafts member for restricting the movement of said reflector when said movable portion is operated as a support shaft.
The semiconductor device manufacturing method according to the present invention includes a reaction vessel provided in an internal heating space, and a center of a substrate in the reaction vessel at a cylindrical end portion of a heating element arranged in a cylindrical shape so as to surround the reaction vessel. A plurality of reflectors having a size exceeding the peripheral edge of the reaction vessel from a portion, a movable part connected to one end located at the center of each of the plurality of reflectors and moving the plurality of reflectors; and A heating device provided with a moving mechanism having a plurality of support shafts that are connected to at least the other end sides of the plurality of reflectors and restrict the movement of the reflectors as support shafts when the movable part operates. The step of carrying the substrate into the reaction vessel and the movement mechanism move based on the in-plane deviation between the peripheral portion and the central portion of the substrate, thereby reducing the in-plane deviation between the peripheral portion and the central portion of the substrate. To let the heat from the heating element With the a step of reflecting the state is changed, and a step of heating the reaction vessel by the heat rays reflected from the plurality of reflectors and the heating element to process the substrate.

  The present invention is, for example, film formation by oxidation treatment, diffusion treatment, carrier activation after ion implantation or planarization, annealing, and thermal CVD reaction on a semiconductor wafer on which a semiconductor integrated circuit device (semiconductor device) is formed. It can utilize for the substrate processing apparatus used for a process etc. The present invention is effective for a process in such a substrate processing apparatus particularly in a low temperature region.

It is a schematic sectional drawing of the processing furnace using the conventional heating apparatus. It is a longitudinal cross-sectional view which shows the outline of the substrate processing apparatus in this invention. FIG. 3 is a cross-sectional view in the vicinity of the ceiling portion of FIG. It is the A section enlarged view in FIG. It is the B section enlarged view in FIG. It is the C section enlarged view in FIG. It is the D section enlarged view in FIG. It is an enlarged view of the ceiling part in FIG. It is EE sectional drawing in FIG. It is the D section enlarged view in Drawing 2 showing an example of the state of the reflector at the beginning of temperature rising. It is the D section enlarged view in FIG. 2 which shows an example of the state of the reflector just before completion of temperature rising. It is EE sectional drawing in FIG. 8 which shows the reflector shape of other embodiment which concerns on this invention.

Explanation of symbols

   1: substrate processing device, 3: heating device, 4: main control device, 4a: temperature monitoring unit, 4b: heating control unit, 4c: reflection control unit, 4d: first flow rate control unit, 4e: pressure control unit, 4f : Second flow controller, 4g: Exhaust controller, 4h: Drive controller, 5a: Flow controller, 5b: Flow controller, 5x: Reaction gas introduction pipe, 5y: Cooling gas supply line, 6a: Pressure controller , 6x: reaction gas exhaust pipe, 7: cooling gas supply line, 7a: open / close valve, 7b: quenching pipe, 7x: intake attachment, 7y: cooling gas introduction duct, 8: forced exhaust line, 8a: exhaust blower, 10: Ceiling part, 11: Intermediate part, 12: Lower part, 13: Terminal case, 14: Airway (cooling medium flow passage), 18: Heating space, 20: Heating element, 20a: Bending part, 21: Upper turning part, 22 : Lower folding part, 23: Wire part, 24: Clearance, 30: Hanging insulator, 31: Upper insulator, 32: Lower insulator, 33: Upper bracket, 34: Lower bracket, 34a: Clearance, 35: Pin, 36: Bo 40: quenching pipe, 40a: through hole, 40b: trough, 40d: penetration, 42: quenching pipe, 50: inner shell (side wall inner layer), 50s: gap, 50t: first flange, 50u : Insulation blanket, 50x: Second flange, 50y: Insulation blanket, 51: Connection insulator, 52: First bolt, 53: Collar, 54: Second bolt, 55a: Opening (first opening), 55b: Box (partition body), 55c: 鍔, 55x: Screw, 59: Water-cooled pipe, 60: Outer shell (side wall middle layer), 60x: Third flange, 60y: Thermal insulation blanket, 61: Pipe, 61a: Opening, 62: Column, 62a: rivet, 65: opening (second opening), 65a: gap, 70: decorative panel (side wall outer layer), 71: screw, 72a: bottom lid, 72b: coil wall, 81: exhaust conduit, 81a: exhaust port , 82: first aperture, 83: second aperture, 90: reflector, 91: reflector, 91a: gap, 92: moving mechanism, 93: shaft, 94: center plate, 95: Bolt, 99: Actuator, 100: Mounting structure, 101: Temperature sensor (temperature detector), 102: Thermocouple contact (temperature detector), 103: Protection tube, 103x: Clearance, 103y: Clearance, 104: Insulator tube, 105: inner cage, 106: outer cage, 107: insulator, 108: terminal, 109a: metal tube, 109b: set screw, 111: first packing, 111a: hole, 112: second packing, 112a: hole, 120a ~ c: Screw, 121: Temperature sensor (temperature detector), 125: Inner cage, 126: Outer cage, 127: Inner box, 128: Outer box, 129: Packing, 131: Temperature sensor (temperature detector), 132: Temperature sensor (temperature detector), 133: protection tube, 135a to c: dredging, 300: boat, 305: wafer, 308: processing chamber, 309: reaction vessel, 310: reaction tube, 315: heat equalizing tube, 317: soaking Heat pipe space, 320: L-type temperature sensor (temperature detector), 321: Contact (temperature detector), 322: Contact (temperature detector), 330: Temperature sensor (temperature detector), Z1 to Z5: Zone , H1 to H3: through hole, R: arc direction, V: penetration direction

Claims (5)

A wall surrounding the heating space;
A heating element arranged in a cylindrical shape inside the wall,
A plurality of reflectors arranged to cover from the center of the heating space to the peripheral edge of the heating space at the cylindrical end of the heating element, and reflecting the heat rays from the heating element;
A movable part connected to one end located in the central part of each of the plurality of reflectors and moving the plurality of reflectors;
A heating device comprising: a plurality of support shafts that are connected to at least the other end sides of the plurality of reflectors and restrict movement of the reflectors as support shafts when the movable portion operates. 2. The heating device according to claim 1, wherein one of the cylindrical end portions of the heating element is located on a ceiling wall body side that is one of the wall bodies, and the plurality of reflectors are disposed on the ceiling wall body side. The heating device according to claim 2, wherein the plurality of reflectors are curved so as to protrude toward the ceiling wall body. A reaction vessel for processing the substrate;
A heating device disposed on the outer periphery of the reaction vessel and heating the substrate in the reaction vessel;
The heating device includes a heating element arranged in a cylindrical shape so as to surround the reaction container, and a cylindrical shape of the heating element having a size exceeding the peripheral part of the reaction container from the center of the substrate in the reaction container. A plurality of reflectors arranged at the ends and reflecting the heat rays of the heating element;
A moving mechanism for moving the plurality of reflectors to change the reflection state of the heat rays;
A controller for controlling the moving mechanism based on an in-plane deviation between the peripheral edge and the center of the substrate;
The moving mechanism is connected to one end side located at the central portion of each of the plurality of reflectors and is movable to move the plurality of reflectors, and at least connected to the other end side of each of the plurality of reflectors. A substrate processing apparatus comprising: a plurality of support shaft bodies that regulate movement of the reflector as support shafts when the movable portion operates. A reaction vessel is installed in the internal heating space,
A plurality of reflectors having a size exceeding the peripheral edge of the reaction vessel from the center of the substrate in the reaction vessel at the cylindrical end of the heating element arranged in a cylindrical shape so as to surround the reaction vessel,
A movable part connected to one end side of each of the plurality of reflectors, the movable part being movable, and connected to at least the other end side of each of the plurality of reflectors, the movable part being In a heating device provided with a moving mechanism having a plurality of support shafts that regulate the movement of the reflector as a support shaft when operating,
Carrying the substrate into the reaction vessel;
The movement mechanism moves based on the in-plane deviation between the peripheral portion and the central portion of the substrate, and the state of reflection of the heat rays from the heating element is reduced so as to reduce the in-plane deviation between the peripheral portion and the central portion of the substrate. The process to be changed,
A method for manufacturing a semiconductor device, comprising: heating the inside of the reaction vessel with the heating element and a heat ray reflected from the plurality of reflectors to process the substrate.

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