JP5453072B2 - Semiconductor substrate heat treatment equipment - Google Patents

Description

  The present invention relates to a semiconductor substrate heat treatment apparatus, and more particularly to a semiconductor substrate heat treatment apparatus suitable for controlling the temperature of an object to be heated when a substrate such as a large-diameter wafer is processed.

  As an apparatus for heat-treating a substrate such as a semiconductor wafer using induction heating, those disclosed in Patent Document 1 and Patent Document 2 are known. As shown in FIG. 11, the heat treatment apparatus disclosed in Patent Document 1 is a batch-type heat treatment apparatus, in which wafers 2 stacked in multiple stages are placed in a quartz process tube 3, and graphite or the like is placed on the outer periphery of the process tube 3. The heating tower 4 formed of the conductive member is disposed, and the solenoid-like induction heating coil 5 is disposed on the outer periphery thereof. According to the heat treatment apparatus 1 having such a configuration, the heating tower 4 is heated by the influence of the magnetic flux generated by the induction heating coil 5, and the wafer 2 disposed in the process tube 3 is heated by the radiant heat from the heating tower 4. The

  Further, as shown in FIG. 12, the heat treatment apparatus disclosed in Patent Document 2 is a single-wafer type heat treatment apparatus, in which a susceptor 7 divided into concentric circles is formed of graphite or the like, and the upper surface of the susceptor 7 is formed. A wafer 8 is placed on the side, and a plurality of annular induction heating coils 9 are arranged concentrically on the lower surface side to enable individual power control for the plurality of induction heating coils 9. According to the heat treatment apparatus 6 having such a configuration, since heat transfer between the susceptor 7 positioned in the heating range by each induction heating coil 9 and the other susceptor 7 is suppressed, power control for the induction heating coil 9 is performed. This improves the temperature distribution controllability of the wafer 8.

  In Patent Document 2, it is described that the distribution of heat generation is favorably controlled by dividing the susceptor 7 on which the wafer 8 is placed. However, in Patent Document 3, the cross-sectional shape of the susceptor is devised. It is disclosed to improve the heat generation distribution. The heat treatment apparatus disclosed in Patent Document 3 pays attention to the fact that the heat generation amount is reduced on the inner side where the diameter of the induction heating coil formed in an annular shape is small, and by increasing the thickness of the inner part of the susceptor, The inner part is closer to the induction heating coil than the part, and the amount of heat generation and the heat capacity are increased.

JP 2004-71596 A JP 2009-87703 A JP 2006-100067 A

  However, in any of the heat treatment apparatuses configured as described above, the magnetic flux acts perpendicularly to the graphite. For this reason, when a metal film or the like is formed on the surface of the wafer as an object to be heated, the wafer may be directly heated, and temperature distribution control may be disturbed.

  On the other hand, it is considered that direct heating of the wafer can be suppressed if the heating is promoted by applying a horizontal magnetic flux to the graphite (susceptor). In this case, the temperature distribution in the horizontal plane is controlled. It becomes difficult.

  Accordingly, the present invention provides a semiconductor substrate heat treatment apparatus that solves the above-described problems, enables temperature distribution control of the susceptor horizontal plane even when a horizontal magnetic flux is applied to the susceptor, and enables heat treatment by batch processing. The purpose is to do.

In order to achieve the above object, a semiconductor substrate heat treatment apparatus according to the present invention is a semiconductor substrate heat treatment apparatus that indirectly heats an object to be heated placed on a horizontally arranged susceptor by inductively heating the susceptor. An induction heating coil group comprising a plurality of induction heating coils arranged on the outer peripheral side of the susceptor and forming an alternating magnetic flux in a direction parallel to the surface of the object to be heated in the susceptor, and the plurality of induction heating coils A power control unit that selects an induction heating coil that inputs current from the inside, and a rotary table that rotates the susceptor, and the susceptor is provided in a plurality of stages in a vertical direction, and the induction heating coil group includes: plural vertically along the susceptor provided in the vertical direction, adjacent disposed Rutotomoni, all induction heating coils which constitute said induction heating coils, the susceptor Is arranged the center of the range of less than 180 degrees as a base point, the power control unit is characterized by having a zone control means for individually controlling the power ratio to be introduced to the induction heating coils disposed adjacent And

In the semiconductor substrate heat treatment apparatus having the above-described features, an outer edge temperature sensor for detecting the temperature of the outer edge portion of the susceptor provided in each heating region by the induction heating coil group is provided on the outer peripheral side of the susceptor. The power control unit receives a temperature of the outer edge portion of the susceptor detected by the outer edge temperature sensor, and transmits a signal indicating a ratio of electric power to be applied to each of the induction heating coil groups to the zone control unit. It is advisable to provide temperature control means.
With this configuration, it is possible to control the temperature distribution of the susceptors stacked in the vertical direction.

Further, in the semiconductor substrate heat treatment apparatus having the above-described characteristics, a center temperature sensor for detecting the center temperature of the susceptor disposed at the lowest stage is provided, and the temperature control means is configured to detect the center temperature sensor. An induction heating coil that compares the temperature of the center of the susceptor with the temperature of the outer edge of the susceptor detected by the outer edge temperature sensor and inputs current from the plurality of induction heating coils that constitute the induction heating coil group It is desirable to have a configuration for outputting a signal for selecting.
By adopting such a configuration, it becomes possible to control the temperature distribution in the horizontal direction (in-plane) in addition to the vertical direction.

Further, in the semiconductor substrate heat treatment apparatus having the above-described features, the plurality of induction heating coils constituting the induction heating coil group may have a core inside a coil to be wound.
By setting it as such a structure, spreading | diffusion of magnetic flux can be suppressed and a heating efficiency can be improved.

Furthermore, in the semiconductor substrate heat treatment apparatus having the above-described characteristics, each of the cores arranged inside the plurality of induction heating coils may be connected to a single core body.
With such a configuration, when an induction heating coil is combined and operated, it can be handled as one electromagnet.

According to the semiconductor substrate heat treatment apparatus having the above-described characteristics, it is possible to control the temperature distribution in the susceptor horizontal plane even when a horizontal magnetic flux is applied to the susceptor. Further, it is possible to control the vertical temperature distribution in the heat treatment by batch processing. Moreover, by setting it as such a structure, the arrangement | positioning range of an induction heating coil can be narrowed and size reduction of an induction heating apparatus can be achieved. Furthermore, even when the arrangement of the induction heating coils is deviated from the center of the susceptor, the susceptor can be heated uniformly.

It is a block diagram which shows the side surface structure of the induction heating apparatus which concerns on 1st Embodiment. It is a block diagram which shows the upper surface structure of the induction heating apparatus which concerns on 1st Embodiment. It is a figure which shows the structure of the susceptor used for embodiment. It is a figure which shows the passage route of the magnetic flux in the induction heating apparatus which concerns on embodiment. It is a figure which shows the mode of the magnetic flux which passes a susceptor inner surface, and the eddy current which arises in an inner surface. It is a block diagram which shows the side surface structure of the induction heating apparatus which concerns on 2nd Embodiment. It is a block diagram which shows the upper surface structure of the induction heating apparatus which concerns on 2nd Embodiment. It is a figure which shows the control flow in a temperature control means. It is a block diagram which shows the side surface structure of the induction heating apparatus which concerns on 3rd Embodiment. It is a figure which shows the example of the induction heating apparatus provided with a bell jar inside a chamber. It is a figure which shows the structure of the conventional batch type induction heating apparatus. It is a figure which shows the structure of the conventional single wafer type induction heating apparatus.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of a semiconductor substrate heat treatment apparatus of the present invention will be described in detail with reference to the drawings. First, a schematic configuration of a semiconductor substrate heat treatment apparatus (hereinafter simply referred to as a heat treatment apparatus) according to the first embodiment will be described with reference to FIG. 1 is a partial cross-sectional block diagram showing a side configuration of the heat treatment apparatus, and FIG. 2 is a partial cross-sectional block diagram showing a top configuration of the heat treatment apparatus.

The heat treatment apparatus 10 according to the present embodiment is of a batch type in which heat treatment is performed by stacking a wafer 23 as an object to be heated and a susceptor 18 as a heating element in multiple stages.
The heat treatment apparatus 10 includes a boat 12 in which wafers 23 and a susceptor 18 are stacked in multiple stages, a chamber 24 that accommodates the boat 12, an induction heating coil group 27 (27A to 27C) that heats the susceptor 18, and an induction heating coil group 27. And a power supply unit 40 for supplying electric power.

  The susceptor 18 may be made of a conductive member, and may be made of, for example, graphite, SiC, SiC-coated graphite, refractory metal, or the like. As shown in FIG. 3, the susceptor 18 in the present embodiment has a circular planar shape (see FIG. 3B), and a cross-sectional shape that is convex downward (see FIG. 3A). Specifically, the central portion and the outer edge portion of the susceptor are made different in thickness, and the outer edge portion is inclined to the main surface opposite to the wafer mounting surface so that the outer edge portion is thinner than the central portion. A surface is formed. In the present embodiment, the inclined surface provided on the opposite main surface has a stepwise inclination angle. This is because it becomes possible to finely adjust the relationship between heating efficiency and thickness, which will be described in detail later.

  The hole 20 provided on the outer edge side and the hole 20a provided in the central portion of the opposite main surface are for fitting the support member 14 constituting the boat 12. The support member 14 may be made of quartz or the like that is not affected by heating due to electromagnetic induction.

  Further, the boat 12 in the present embodiment is mounted on a turntable 16 having a motor (not shown), and can rotate the susceptor 18 and the wafer 23 during the heat treatment process. By adopting such a configuration, it is possible to suppress an uneven distribution of heat generation when the susceptor 18 is heated. Further, as will be described in detail later, the susceptor 18 can be uniformly heated even when the arrangement of the induction heating coils 26 (26aA to 26cC), which are heating sources, is biased from the center of the susceptor 18. Become.

  The chamber 24 is made of, for example, an aluminum plate, and accommodates the boat 12 therein by forming a circular or polygonal (hexagonal in this embodiment) side wall. By adopting such a configuration, it is possible to prevent the diffusion of heat and the heating of the core 28 to be described in detail later.

  Each of the induction heating coil groups 27 according to the embodiment is configured by three induction heating coils 26 (26aA to 26cA, or 26aB to 26cB, or 26aC to 26cC) arranged on the circumference on the outer peripheral side of the susceptor 18. .

  Each induction heating coil 26 is configured by winding a copper wire around a core 28 disposed on the outer peripheral side of the boat 12. In the heat treatment apparatus 10 according to the embodiment, the core body 30 formed in an arc shape is projected toward the boat 12 so as to form three magnetic pole faces 34 (34a to 34c) with respect to one core 28. The induction heating coil 26 is wound around each of the three convex portions 32 (32a to 32c). The core 28 may be made of a ferrite-based ceramic or the like, and may be formed by firing after forming a clay-like raw material. This is because it is possible to freely form a shape by using such a member. Further, by using the core 28, the diffusion of the magnetic flux can be prevented as compared with the case of the induction heating coil 26 alone, and highly efficient induction heating in which the magnetic flux is concentrated can be realized.

  The induction heating coil 26 is wound around the outer periphery of the convex portion 32 formed on the core 28. For this reason, the central axis in the winding direction of the induction heating coil 26 and the central axis in the mounted state of the wafer 23 or the susceptor 18 face in a direction perpendicular to each other, and the tip surface of the convex portion 32 facing the susceptor 18 is a magnetic pole. It becomes the surface 34. With such a configuration, an alternating magnetic flux is generated in a direction parallel to the wafer mounting surface of the susceptor 18 from the magnetic pole surface 34 around which the induction heating coil 26 is wound. Each magnetic pole surface 34 is formed so as to face the center of the susceptor 18 and may be disposed within an angle of less than 180 degrees with the center of the susceptor 18 as a base point. In this embodiment, the magnetic pole faces 34 are spaced by 60 degrees. Thus, the three induction heating coils 26aA to 26cA (26bA to 26bC, 26cA to 26cC) are arranged in a range of 120 degrees. By adopting such an angular relationship, it is possible to reduce the arrangement of the cores 28 while generating a magnetic flux passing through the center of the susceptor 18.

  Each induction heating coil 26 is preferably a tubular member (for example, a copper tube) having a hollow inside. This is because the heating of the induction heating coil 26 itself can be suppressed by inserting a cooling member (for example, cooling water) into the copper tube during the heat treatment.

  The induction heating coil group 27 constituted by a plurality (three in the present embodiment) of induction heating coils 26 as described above is provided in the vertical direction along the boat 12 in which the susceptor 18 and the wafer 23 are stacked in the vertical direction. (Three in the present embodiment) are arranged adjacent to each other. With such a configuration, it is possible to arrange more susceptors 18 and wafers 23 in one chamber 24, and heat treatment of the wafers 23 can be performed efficiently. . Further, if power control is individually performed on the induction heating coil group 27 arranged in layers, the temperature distribution in the vertical direction in the plurality of susceptors 18 arranged in the boat 12 can be controlled, and the susceptor 18 can be controlled. It is also possible to suppress the temperature variation between.

  The three induction heating coil groups 27 configured as described above are connected to a single power supply unit 40. The power supply unit 40 is provided with an inverter (not shown) and an AC power supply (not shown). A power control unit 42 is connected to the power supply unit 40 to adjust the current, voltage, frequency, etc. supplied to the induction heating coil group 27. It is configured to be able to. Here, when a resonance type inverter is adopted as the inverter, a resonance circuit corresponding to each control frequency is connected in parallel so that the frequency can be easily switched, and this is connected to a signal from the power control unit 42. It is desirable to be able to switch according to In addition, when a non-resonant type inverter is employed as an inverter, for example, a PWM type inverter is employed, so that operation at a frequency corresponding to a signal from the power control unit 42 can be performed. By adopting such a configuration, it is possible to realize frequency switching during operation.

  The power control unit 42 according to the embodiment includes zone control means 44. The zone control means 44 plays a role of performing power control on each induction heating coil group 27 while avoiding the influence of mutual induction occurring between the adjacent induction heating coil groups 27.

  Since the plurality of induction heating coils 26 constituting each induction heating coil group 27 are operated, power of the same frequency, the same current, and the same voltage is input to two induction heating coils 26 by one or a combination. The treatment can be regarded as a single induction heating coil. For this reason, even if a plurality of induction heating coils 26 are arranged adjacent to each other, mutual induction does not occur between the induction heating coils 26 adjacent to each other at the time of operation, and there is no need to consider the influence thereof.

However, since the induction heating coil group 27 arranged in a stack is operated as an individual induction heating coil, the induction heating coils 26 adjacent to each other in the vertical direction (for example, the induction heating coil 26aA and the induction heating coil 26aB, the induction heating coil). mutual induction occurs in the induction heating coil 26 aC, etc.) and 26aB, sometimes adversely affect the individual power control. For this reason, the zone control means 44 matches the frequency of the current supplied to the adjacent induction heating coil group 27 based on the detected current frequency and waveform (current waveform), and synchronizes the phase of the current waveform. (Estimating the phase difference to 0 or approximating the phase difference to 0) or power control that avoids the influence of mutual induction between the adjacent induction heating coil groups 27 by controlling to maintain a predetermined phase difference ( Zone control control).

Such control frequency of the current value and current being introduced to the induction heating coil constituting each induction heating coil group 27 (e.g. induction heating coil 26aA and the induction heating coil 26 aB, and the induction heating coil 26 aC), And the voltage value and the like are detected and input to the zone control means 44. The zone control means 44 detects the phase of the current waveform between the induction heating coil groups 27 and controls the induction heating coil group 27 with respect to the power supply unit 40 in order to control it in synchronization or to maintain a predetermined phase difference. This is done by outputting a signal that instantaneously changes the frequency of the current input to the.

  Further, regarding power control, a signal to be changed in units of elapsed time from the start of heat treatment based on a control map (vertical temperature distribution control map) stored in a storage means (memory) (not shown) provided in the power control unit 42. May be output to the power supply unit 40. The control map corrects the temperature change between the stacked susceptors 18 from the start of the heat treatment to the end of the heat treatment, and obtains an arbitrary temperature distribution (for example, a uniform temperature distribution). What is necessary is just to have recorded the electric power value to be given with the elapsed time from the start of heat treatment.

  The power supply unit 40 instantaneously adjusts the frequency of the current input to the induction heating coil group 27 based on a signal from the power control unit 42 (including the zone control unit 44), and performs phase control of the current waveform. By implementing power control between the induction heating coil groups 27, the temperature distribution in the vertical direction in the boat 12 can be controlled.

  In the power control unit 42 according to the present embodiment, the storage unit also stores a control map (horizontal temperature distribution control map) in which selection of the induction heating coil 26 and frequency control are recorded in accordance with changes in the in-plane temperature distribution of the susceptor 18. doing. Therefore, the power control unit 42 controls the range of horizontal magnetic flux generated through the induction heating coil 26 and the frequency of the applied current, that is, the heating region of the susceptor 18 by a signal output to the power supply unit 40 together with the heat treatment time. Can be done. In the horizontal temperature distribution control map stored in the power control unit 42, the heating area is divided on concentric circles so that a higher frequency current is supplied to the induction heating coil 26 as the outer heating area is heated. A control signal is output, and the control signal is output so that a current having a lower frequency is supplied to the induction heating coil 26 as the inner heating region is heated.

  In the heat treatment apparatus 10 according to the embodiment, the induction heating coil 26aA (26aB, 26aC) and the induction heating coil 26bA, 26cA (26bB, 26cB, 26bC, 26cC) are electrically separated from the inverter (power supply unit 40). Connected so that it can be connected. When the winding directions of the induction heating coil 26aA (26aB, 26aC), the induction heating coil 26bA (26bB, 26bC), and the induction heating coil 26cA (26cB, 26cC) are the same, the induction heating coil 26aA (26aB) , 26aC) and induction heating coils 26bA, 26cA (26bB, 26cB, 26bC, 26cC) are connected to the inverter (power supply unit 40) so that a current in an opposite phase flows. By adopting such a configuration, the magnetic flux generated by flowing current through the induction heating coil 26aA (26aB, 26aC) and the magnetic flux generated by flowing current through the induction heating coil 26bA, 26cA (26bB, 26cB, 26bC, 26cC). , And the polarities of the magnetic pole surface 34a, which is the tip of the convex portion 32, and the magnetic pole surfaces 34b and 34c are reversed. Therefore, when a magnetic flux is generated by a combination of the induction heating coil 26aA and the induction heating coil 26bA or a combination of the induction heating coil 26aA and the induction heating coil 26cA, a magnetic flux passing between the magnetic pole surfaces 34 to be combined is generated. It becomes possible. The direction of the magnetic flux to be generated may be determined by reversing the polarity of the magnetic pole surface 34 by reversing the winding direction of the induction heating coil 26 with the same connection form.

  Moreover, it is desirable to arrange a heat insulating material 36 on the tip side of the convex portion 32 constituting the magnetic pole surface 34 so as to suppress heating of the core 28 and the induction heating coil 26. The heat insulating material 36 may be a ceramic plate or the like, and for example, a plate member made of porous alumina is preferable.

  Here, regarding the relationship between the induction heating coil group 27 and the chamber 24, the following is preferable. That is, the core body 30 constituting the induction heating coil group 27 is disposed outside the chamber 24, the induction heating coil 26 is wound around, and the convex portions 32 constituting the magnetic pole surface 34 are respectively side walls constituting the chamber 24. It is made to project into the inside of the chamber 24 from the hole 24a provided in the inside. Therefore, as shown in FIGS. 1 and 2, the heat insulating material 36 may be directly fixed to the tip (magnetic pole surface 34) of the convex portion 32, but is fixed using the side wall constituting the chamber 24. May be. Further, in order to suppress heating of the side walls constituting the chamber 24, a cooling mechanism may be provided outside the chamber 24. With such a configuration, the core body 30 can be disposed outside the side wall constituting the chamber 24, and the magnetic pole surface 34 can be disposed in the vicinity of the susceptor 18, improving heating efficiency and heating the core 28. Two effects such as suppression can be achieved.

  According to the heat treatment apparatus 10 having such a configuration, it is possible to control switching of the induction heating coil 26 that supplies current, so that the induction heating coil 26aA is operated alone, and the induction heating coil 26aA and the induction heating coil 26bA are switched. The operation by the combination and the operation by the combination of the induction heating coil 26aA and the induction heating coil 26cA can be respectively performed. The passage of magnetic flux (flux generation range) generated in each operation mode is roughly as shown in FIG.

  That is, when the induction heating coil 26aA is operated alone, a magnetic flux (arrow A) centered on the convex portion 32a is generated, the magnetic flux passing path is in the vicinity of the magnetic pole surface 34a, and the magnetic flux generation range is the susceptor 18. It becomes only the outer edge part. Next, in the case of operation with the combination of the induction heating coil 26aA and the induction heating coil 26bA, a magnetic flux as shown by an arrow B going back and forth between the magnetic pole surface 34a and the magnetic pole surface 34b is generated. For this reason, the path of the magnetic flux passes through the inner peripheral side of the susceptor 18 as compared with the case where the induction heating coil 26aA is operated alone, and the generation range of the magnetic flux is the inner periphery as compared with the case where the induction heating coil 26aA is operated alone. Will spread to the side. Further, when the induction heating coil 26aA and the induction heating coil 26cA are operated in combination, a magnetic flux as indicated by an arrow C that moves back and forth between the magnetic pole surface 34a and the magnetic pole surface 34c is generated. For this reason, the passage route of the magnetic flux passes through the approximate center of the susceptor 18, and the generation range of the magnetic flux is also near the center of the susceptor 18.

  FIG. 5 is a diagram showing a state of magnetic flux passing through the susceptor 18 when a current is supplied to the induction heating coil 26 (when it is operated) in a cross section of the susceptor 18. 5A shows the state of magnetic flux when a current in a high frequency band (60 kHz in this embodiment) is supplied to the induction heating coil 26, and FIG. 5B shows the low frequency band ( The state of the magnetic flux when a current of 20 kHz is applied in this embodiment is shown. In FIG. 5, the range indicated by the solid line indicates the range when the induction heating coil 26aA is operated alone, and the range indicated by the broken line is the range when the induction heating coil 26aA and the induction heating coil 26bA are operated in combination. The range indicated by the alternate long and short dash line indicates the range when the induction heating coil 26aA and the induction heating coil 26cA are operated in combination. In the heat treatment apparatus 10 according to the embodiment, since magnetic flux is applied to the susceptor 18 from the horizontal direction, the cross-sectional shape of the susceptor 18 is tapered, so that the magnetic flux extends closer to the center of the susceptor 18 than the flat plate type susceptor. Is easier to reach.

  As described above, in the heat treatment apparatus 10 according to the present embodiment, the susceptor 18 is heated by the horizontal magnetic flux by controlling the frequency of the input current to the induction heating coil 26 and the combination of the induction heating coils for supplying the current in a time-sharing manner. Even in such a case, it is possible to adjust the heating range of the susceptor 18 and arbitrarily control the temperature distribution in the susceptor 18 (wafer 23) surface.

  In addition, the heat treatment apparatus 10 according to the present embodiment can control the heating range in the susceptor 18 by supplying current by arbitrarily combining the induction heating coils 26, thereby changing the arrangement range angle of the induction heating coils 26. It became possible to make it smaller. For this reason, it was possible to reduce the size of the heat treatment apparatus.

  Further, the heat treatment apparatus 10 according to the present embodiment can avoid the influence of mutual induction occurring in the induction heating coil group 27 arranged in a stack, and can individually control the power supplied to the induction heating coil group 27. As a result, it is possible to arbitrarily control the temperature distribution generated between the plurality of susceptors 18 arranged in a stacked manner.

  Further, according to the heat treatment apparatus 10 having the above-described configuration, even when a conductive member such as a metal film is formed on the surface of the wafer 23, current cancellation occurs in the metal film, and thus heat generation. This occurs only in the susceptor 18 and there is no possibility that the temperature distribution of the wafer 23 is disturbed.

  In the present embodiment, it is described that the cross-sectional shape of the susceptor 18 is a downwardly convex mountain shape. However, a susceptor with a constant cross-sectional thickness can also be employed in the heat treatment apparatus 10 according to the present embodiment.

  Next, a second embodiment according to the heat treatment apparatus of the present invention will be described with reference to FIGS. 6 is a partial cross-sectional block diagram showing a side configuration of the heat treatment apparatus, and FIG. 2 is a partial cross-sectional block diagram showing a top configuration of the heat treatment apparatus. Further, most of the configuration of the heat treatment apparatus 10A according to the present embodiment is the same as that of the heat treatment apparatus 10 according to the first embodiment described above. Therefore, the same reference numerals are given to portions having the same configuration, and detailed description thereof is omitted.

  The difference between the heat treatment apparatus 10A according to the present embodiment and the heat treatment apparatus 10 according to the first embodiment is that the temperature control means 46 is provided in the power control unit 42 and the temperature of the outer edge of the susceptor 18 is detected. The outer edge temperature sensor 48 (48A to 48C) is provided.

  The temperature control means 46 outputs a signal for determining the proportion of electric power to be applied to each induction heating coil group 27 to the zone control means 44 based on the temperature detected by the outer edge temperature sensor 48 described later in detail.

  The output of the control signal by the temperature control means 46 is made based on a control flow as shown in FIG. First, the temperature is detected by the outer edge temperature sensor 48 (step 10). Next, the detected temperature is compared with a predetermined target temperature, and the deviation is obtained (step 20). Based on the obtained deviation, the power output ratio is determined (step 30). A signal indicating the determined output ratio is output to the zone control means 44 (step 40). After the signal output, the process returns to Step 10 again to perform PID control.

  At least one outer edge temperature sensor 48 is provided for each heating zone of the induction heating coil groups 27A, 27B, and 27C. It is because the heating balance in the stacking direction by the induction heating coil group 27 can be detected by adopting such an arrangement form. The temperature detected by each outer edge temperature sensor 48 is transmitted to the temperature control means 46 described above.

  According to the heat treatment apparatus 10A having such a configuration, it is possible to control the temperature balance while detecting the temperature distribution in the vertical direction. This eliminates the need for the power control unit 42 to store the vertical temperature distribution control map. In addition, about another structure, an effect | action, and an effect, it is the same as that of the heat processing apparatus 10 which concerns on 1st Embodiment mentioned above.

  Next, a third embodiment according to the heat treatment apparatus of the present invention will be described with reference to FIG. FIG. 9 is a partial cross-sectional block diagram showing the side structure of the heat treatment apparatus. Further, most of the configuration of the heat treatment apparatus 10B according to the present embodiment is the same as the heat treatment apparatus 10 according to the first embodiment and the heat treatment apparatus 10A according to the second embodiment. Therefore, the same reference numerals are given to portions having the same configuration, and detailed description thereof is omitted.

  A characteristic configuration of the heat treatment apparatus 10B according to the present embodiment is that a center temperature sensor 50 is provided. The center temperature sensor 50 is provided, for example, in the turntable 16 and plays a role of detecting the temperature near the center of the susceptor 18 located at the lowest stage of the boat 12. The detected temperature is transmitted to the temperature control means 46.

  In the heat treatment apparatus 10B having such a configuration, the in-plane of the susceptor 18 is based on the temperature near the center of the susceptor 18 detected by the center temperature sensor 50 and the temperature of the outer edge of the susceptor 18 detected by the outer edge temperature sensor 48. Know the temperature distribution. The temperature control means 46 determines the power output ratio to the induction heating coil 26 to obtain an arbitrary temperature distribution (for example, uniform temperature distribution) based on the grasped in-plane temperature distribution of the susceptor 18, and operates the induction heating coil to be operated. 26 is selected and the ratio of the current frequency is determined and output to the power supply unit 40 as a control signal.

  According to the heat treatment apparatus 10B having such a configuration, it is possible to control the temperature balance while detecting the temperature distribution in the horizontal direction (in-plane) in addition to the temperature distribution in the vertical direction. For this reason, it is not necessary to store the vertical temperature distribution control map and the horizontal temperature distribution control map in the power control unit 42. In addition, about another structure, an effect | action, and an effect, it is the same as that of the heat processing apparatus 10 which concerns on 1st Embodiment mentioned above.

  In any of the above embodiments, the chamber 24 is made of an aluminum plate or the like, the magnetic pole surface 34 of the induction heating coil 26 protrudes inside, and the rotary table 16, the susceptor 18, and the wafer 23 are arranged as they are in the internal region. As shown. However, from the viewpoint of suppressing contamination on the wafer 23 that is the member to be processed, a bell jar 39 may be provided inside the chamber 24 as shown in FIG. It is because the contamination with respect to the wafer 23 can be suppressed by covering the boat 12 including the turntable 16 with the bell jar 39. The bell jar may be a heat-resistant member having permeability such as quartz.

DESCRIPTION OF SYMBOLS 10 ......... Semiconductor substrate heat processing apparatus (heat processing apparatus), 12 ......... Boat, 14 ......... Support member, 16 ......... Rotary table, 18 ......... Susceptor, 20, 20a ......... Hole, 22 ... ... inclined surface, 23 ... ... wafer, 24 ... ... chamber, 24a ... ... hole, 26 (26a, 26b, 26c) ... ... induction heating coil, 28 ... ... core, 30 ... ... core body, 32 (32a, 32b, 32c) ..... Projection, 34 (34a, 34b, 34c) ..... Magnetic pole surface, 36 ..... Insulating material, 39 .... Berja, 40 ..... Power supply part, 42 .. ... Power control unit, 44 ......... Zone control means.

Claims (5)

A semiconductor substrate heat treatment apparatus that indirectly heats an object to be heated placed on a horizontally disposed susceptor by inductively heating the susceptor,
An induction heating coil group comprising a plurality of induction heating coils arranged on the outer peripheral side of the susceptor and forming an alternating magnetic flux in a direction parallel to the object-to-be-heated object mounting surface of the susceptor;
A power control unit that selects an induction heating coil that inputs current from the plurality of induction heating coils ;
A rotating table for rotating the susceptor ,
The susceptor is provided in a plurality of stages in the vertical direction,
The induction heating coil group includes a plurality vertically along the susceptor provided in the vertical direction, adjacent disposed Rutotomoni, all induction heating coils which constitute said induction heating coil group 180 to the center of the susceptor as a base point Placed within a range of less than
The semiconductor substrate heat treatment apparatus, wherein the power control unit includes zone control means for individually controlling a power ratio to be input to the induction heating coil group disposed adjacent to the power control unit. An outer edge temperature sensor for detecting the temperature of the outer edge portion of the susceptor provided in each heating region by the induction heating coil group is provided on the outer peripheral side of the susceptor,
A temperature at which the power control unit receives a temperature of the outer edge of the susceptor detected by the outer edge temperature sensor and transmits a signal indicating a ratio of electric power to be applied to each of the induction heating coil groups to the zone control unit. The semiconductor substrate heat treatment apparatus according to claim 1, further comprising a control unit. A center temperature sensor for detecting the center temperature of the susceptor arranged at the bottom is provided,
The temperature control means compares the center temperature of the susceptor detected by the center temperature sensor with the outer edge temperature of the susceptor detected by the outer edge temperature sensor, and constitutes the induction heating coil group 3. The semiconductor substrate heat treatment apparatus according to claim 2, wherein a signal for selecting an induction heating coil to which an electric current is input from a plurality of induction heating coils is output. Wherein the plurality of induction heating coils which constitute said induction heating coil group includes a semiconductor substrate heat treatment according to any one of claims 1 to 3, characterized in that it has a core inside the coil wound apparatus. The induction heating apparatus according to claim 4 , wherein each of the cores disposed inside the plurality of induction heating coils is connected to a single core body.

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