JP2016171066A - Heater and semiconductor manufacturing device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heater whose life is extended by inhibiting a current from being concentrated on a folding portion of a heater element during energization.SOLUTION: A heater includes: a heater element 16a having a planar heat generating part 160, a linear slit 163 whose one end is arranged in the outer periphery of the heat generating part and other end is arranged in a folding portion of the heat generating part, respectively, and linearly formed as an opening, and a folding part 162 which is formed as the opening continuous to the other end and whose opening diameter is larger than the slit width of the linear slit, and generating heat by energization; and a pair of electrodes 16b, 16c which is connected to a prescribed surface of the heater element and to which a voltage is applied during energization to the heater element.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a heater and a semiconductor manufacturing apparatus using the heater.

  In recent years, along with demands for lowering the cost and higher performance of semiconductor devices, there has been a demand for higher quality such as improvement in film thickness uniformity as well as high productivity in the wafer film forming process.

  In order to satisfy these requirements, a single-wafer epitaxial film forming apparatus is used, for example, a process gas is supplied into the reaction chamber while rotating the wafer at a high speed of 900 rpm or more in the reaction chamber, and a heater composed of a resistance heating element. A backside heating method is used in which the wafer is heated from the backside using the above.

JP-A-10-208855

  In the epitaxial film forming apparatus as described above, it is required to reduce the heat capacity of the heater in order to improve the thermal responsiveness. As a method for reducing the heat capacity of the heater, it is conceivable to reduce the thickness of the heater. However, in order to adjust the heater to a desired electric resistance value, the folded width of the heater must be increased.

  However, the current does not flow uniformly through the heater element but concentrates on the folded portion. As a result, there is a problem that the heater life is shortened due to breakage of the folded portion.

  In view of the above-described problems of the prior art, an object of the present invention is to suppress current concentration at the folded portion of the heater element during energization and extend the life of the heater.

  A heater according to an embodiment of the present invention includes a planar heat generating portion, a linear slit having one end disposed on the outer periphery of the heat generating portion, and the other end disposed in the folded portion of the heat generating portion, and having a linear opening. A heater element that has an opening formed continuously at the other end and has a folded portion whose opening diameter is larger than the slit width of the linear slit, and is connected to a predetermined surface of the heater element, and is connected to a predetermined surface of the heater element. And a pair of electrodes to which a voltage is applied when energized.

  In the heater according to an embodiment of the present invention, the heater element further includes a serpentine slit formed in a serpentine shape in the heat generating portion so that a current flowing from the pair of electrodes into the heat generating portion is equally divided. Is preferred.

  Moreover, in the heater which concerns on one Embodiment of this invention, it is preferable that a meandering slit is parted by the center part of a heat-emitting part.

  In the heater according to an embodiment of the present invention, the linear slit bends in a direction along the concentric circle of the outer edge of the heat generating portion at the end between the predetermined distance from the other end, and the folded portion is the concentric circle on the concentric circle. It is preferable that they are arranged so as to deviate from the center line of the main body by a predetermined angle.

  Moreover, in the heater which concerns on one Embodiment of this invention, it is preferable that the linear slit is chamfered in the end.

  A semiconductor manufacturing apparatus according to an embodiment of the present invention includes a reaction chamber into which a wafer is introduced, a gas supply mechanism that supplies process gas to the reaction chamber, a gas exhaust mechanism that exhausts gas from the reaction chamber, and a wafer. A wafer supporting member to be placed, a rotating member connected to the outer peripheral portion of the wafer supporting member, rotating the wafer, a rotation driving control mechanism connected to the rotating member and controlling the rotational driving of the rotating member, and a heater, It is characterized by providing. The heater has a sheet-like heat generating part, a linear slit that has one end disposed on the outer periphery of the heat generating part and the other end in the folded part of the heat generating part, and a continuous opening at the other end. A heater element that is formed and has a folded portion whose opening width is larger than the slit width of the linear slit, and is connected to a predetermined surface of the heater element that generates heat when energized, and a voltage is applied when the heater element is energized. A pair of electrodes.

  ADVANTAGE OF THE INVENTION According to this invention, the electric current concentration in the folding | returning part of a heater element can be suppressed at the time of electricity supply, and a heater lifetime can be extended.

It is a top view which shows the heater element which comprises the resistance heater of 1st Embodiment. It is a figure explaining the heat_generation | fever distribution around the folding | turning part in the conventional heater element. It is a figure explaining the heat_generation | fever distribution around the folding | turning part in the heater element shown in FIG. It is a figure which shows schematic structure of the semiconductor manufacturing apparatus using the resistance heater of 1st Embodiment. It is a top view which shows the heater element which comprises the resistance heater of 2nd Embodiment. It is a figure which shows the electrical connection of the heater element shown in FIG. It is a top view which shows the heater element which comprises the resistance heater of 3rd Embodiment. It is a figure explaining the heat_generation | fever distribution in the heater element of 1st Embodiment. It is a figure explaining the heat_generation | fever distribution in the heater element shown in FIG. It is a top view which shows the heater element which comprises the resistance heater of 4th Embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
<First Embodiment>
FIG. 1 is a top view showing a heater element 16a constituting a resistance heater which is a heater of the present embodiment. As shown in FIG. 1, the heater element 16 a includes a heat generating portion 160 whose outer shape is a disk shape, and a linear slit 163 that is linearly open. One end of the linear slit 163 is disposed on the outer periphery of the heat generating part 160, and the other end is disposed in the heat generating part 160. Then, a folded portion 162 that is continuously formed at the other end and has an opening diameter larger than the slit width of the linear slit 163 is provided.

  In the present embodiment, the distance in the Y-axis direction in FIG. 1 is a predetermined distance from the ends of the remaining six linear slits 163 except for the two linear slits 163 that are closest to the center point of the heat generating portion 160. An end portion 163c up to D (for example, 5 to 10 mm) is bent in a direction along a concentric circle E on the outer edge of the heater element 16a from the center line of the main body portion 163b which is the X-axis direction portion of the linear slit 163 in FIG. ing.

  Further, each folded portion 162 in the heat generating portion 160 is arranged continuously on the concentric circle E so as to deviate from the center line of the main body portion 163b by a predetermined angle θ continuously with the end portion 163c. As a point-symmetric shape. FIG. 2 is a view for explaining the heat generation distribution around the folded portion 162 in the conventional heater element 16a. Here, it is shown that current concentration occurs in the folded portion 162 and heat is generated until the temperature becomes high. In addition, the temperature gradient is large and the amount of heat generation is also large in the peripheral region of the tip portion.

  On the other hand, FIG. 3 is a view for explaining the heat generation distribution around the folded portion 162 in the heater element 16a of the present embodiment. Here, unlike the case of FIG. 2, the folded portion 162 has an opening diameter W <b> 2 and a width wider than the slit width W <b> 1 of the slit 163. For this reason, the current does not concentrate on one point in the front end portion around the folded portion 162, and the temperature gradient becomes gentle.

  Such a heater element 16a is integrally formed with the heater electrode portions 16b and 16c that support the heater element 16a by adhesion, fusion, or the like, and constitutes a heater. For the heater element 16a and the heater electrode portions 16b and 16c, for example, a SiC sintered body obtained by sintering SiC powder is used. At this time, the electrical resistivity can be adjusted by controlling the impurity concentration added to the SiC powder. Further, it can be processed into a desired shape and thickness. For example, the heater element 16a can have a diameter of φ250 mm and a thickness of 2 mm. In addition, the linear slit 163 and the folding | turning part 162 can be formed by performing a wire electric discharge process to a SiC sintered substrate. Furthermore, a high-purity SiC film is formed on the surface of the heater element to prevent impurity diffusion.

  Such a heater is used as a heater for heating a semiconductor substrate (wafer) from the back surface in a semiconductor manufacturing apparatus.

FIG. 4 is a diagram showing a schematic configuration of a semiconductor manufacturing apparatus using the resistance heater according to the present embodiment. As shown in FIG. 4, the semiconductor manufacturing apparatus has a reaction chamber 10 for performing a film forming process. Gas supply ports 11 a and 11 b are provided in the upper part of the reaction chamber 10. From the gas supply ports 11a and 11b, raw material gases (for example, ammonia gas (NH ₃ gas), trimethylaluminum gas (TMA gas), trimethylgallium gas (TMG gas), triethylgallium gas (TEG gas), triethylindium gas ( TMI gas), Biz (cyclopentadienyl) magnesium gas (Cp ₂ Mg gas), monomethylsilane gas (SiH ₃ CH ₃ gas), monosilane gas (SiH ₄ gas), dichlorosilane gas (SiH ₂ Cl ₂ gas), trichlorosilane gas A process gas including (SiHCl ₃ gas)) and a carrier gas (for example, hydrogen (H ₂ ) gas) is introduced into the reaction chamber 10.

  Further, below the gas supply ports 11a and 11b, a rectifying plate 12 having a large number of holes is disposed so as to face the surface of the wafer w. The rectifying plate 12 supplies the process gas supplied from the gas supply ports 11a and 11b to the surface of the wafer w on the wafer w in a rectified state.

  A susceptor 13 on which the introduced wafer w is placed is provided inside the reaction chamber 10. The outer periphery of the susceptor 13 is fixed to the upper part of the cylindrical rotating member 14. Since the susceptor 13 is in a high temperature state inside the reaction chamber 10, the susceptor 13 is manufactured using, for example, a SiC material. In this embodiment, the disk-shaped susceptor 13 is used as an example of the wafer support member, but an annular holder can also be used.

  The rotating member 14 has a rotating body 14a, a rotating base 14b, and a rotating shaft 14c. The rotating drum 14a is an annular component that supports the outer peripheral portion of the susceptor 13 and is fixed to the upper peripheral portion of the rotating base 14b. A cylindrical rotating shaft 14c is fixed to the rotating base 14b. The axis center of the rotating shaft 14c passes through the center of the wafer w.

  The rotating shaft 14 c extends to the outside of the reaction chamber 10 and is connected to the rotation drive control mechanism 15. The rotation drive control mechanism 15 rotates the susceptor 13 at, for example, 50 to 3000 rpm via the rotation base 14b and the rotation cylinder 14a by rotating the rotation shaft 14c.

  The above-described heater 16 for heating the wafer w from the back surface is provided in the rotating drum 14a. The heater 16 is supported by booth bars 17a and 17b which are arm-shaped electrode parts. The booth bars 17a and 17b are connected to the electrodes 18a and 18b at the end opposite to the side supporting the heater electrode portions 16b and 16c.

  The booth bars 17a and 17b are electrode parts having both conductivity and high heat resistance, and are made of, for example, a C (carbon) material. The electrodes 18a and 18b are metal members such as Mo (molybdenum), and are connected to the booth bars 17a and 17b on the upper end side and connected to an external power source (not shown) on the other end side. For example, a voltage of 115 V and 50 Hz is applied to the electrodes 18a and 18b from the external power source, and the heater element 16a generates heat through the booth bars 17a and 17b and the heater electrode portions 16b and 16c.

  As shown in FIG. 4, radiation thermometers 19 a and 19 b are provided in the upper part of the reaction chamber 10 in order to measure the surface temperature (in-plane temperature) of the wafer w. In this embodiment, a part of the upper wall of the reaction chamber 10 and the rectifying plate 12 are made of transparent quartz, so that temperature measurement by the radiation thermometers 19a and 19b is not hindered by the rectifying plate 12. The radiation thermometers 19 a and 19 b measure the surface temperatures at the center and the outer periphery of the wafer w that change according to the heat generated by the heater 16, and output the temperature data to the temperature control mechanism 20. The temperature control mechanism 20 controls the output of the heater 16 based on the temperature data, and heats the wafer w so that the surface temperature of the wafer w becomes a predetermined film formation temperature (for example, 1100 ° C.).

  As shown in FIG. 4, gas exhaust ports 21 a and 21 b are provided in the lower part of the reaction chamber 10 in order to exhaust the gas containing process gas and reaction by-products that have become excessive during the reaction. . The gas exhaust ports 21 a and 21 b are connected to a gas exhaust mechanism 24 including a regulating valve 22 and a vacuum pump 23, respectively. The gas exhaust mechanism 24 is controlled by a control mechanism (not shown) and adjusts the inside of the reaction chamber 10 to a predetermined pressure.

  Thus, according to the present embodiment, by providing the folded portion 162 of the heater element 16a, current concentration during energization can be significantly suppressed.

  Further, since the current tends to flow at the shortest distance, a region where no current flows and heat is not generated outside the folded portion 162 is generated, but the region where the current flows is formed by inclining the end of the linear slit 163. Can be widened, and further suppression of current concentration can be achieved.

  In this way, by suppressing the current concentration, the heater life can be extended, so that the frequency of replacing the member of the heater can be reduced, and the cost of the semiconductor manufacturing apparatus can be reduced and the downtime can be reduced.

<Second Embodiment>
A second embodiment of the present invention will be described. In addition, the code | symbol common with the code | symbol attached | subjected in 1st Embodiment shows the same object. FIG. 5 is a top view showing the heater element 26a constituting the resistance heater according to this embodiment. As shown in FIG. 5, the heater element 26 a has a heat generating part 260 whose outer shape is a disk, a serpentine slit 261 formed in the heat generating part 260, one end disposed on the outer periphery of the heat generating part 260, and the other end For example, there are eight linear slits 263 in which folded portions 262 of the heat generating portion 260 are formed. The width (diameter) of the folded portion 262 is larger than the slit width of the meandering slit 261 and the linear slit 263.

  The slits 261 and 263 are arranged so that the distances through which currents are separated and flow between the heater electrode portions 26b and 26c and the connection portions 26b ′ and 26c ′ are equal.

  As shown in FIG. 5, when a voltage is applied between the connecting portion 26b 'to the heater electrode portion 26b and the connecting portion 26c' to the heater electrode portion 26c, the heater configured in this way As indicated by the arrows, heat is generated when current flows in two paths by meandering slits 261 and linear slits 263.

  FIG. 6 is a diagram showing an electrical connection of the heater element 26a shown in FIG. Here, as will be described later, the heater element 26a, the heater electrode portions 16b and 16c, the booth bars 17a and 17b, and the electrodes 18a and 18b connected to an external power source are shown to constitute an electric circuit. Further, the heater elements 26a, which are resistance heating elements, are internally arranged in parallel and are connected to the heater electrode portions 16b and 16c, respectively. As described above, since the distance between the two paths through which the current in the heater element 16a flows is equal, the two resistance components R1 and R2 are equal. Therefore, if the amount of current flowing from the heater electrode portions 16b and 16c to the heater element 26a is I, the amount of current in the two paths in the heater element 26a is I / 2.

  As described above, according to the present embodiment, by providing the meandering slit 261, current flows through the heat generating portion 260 of the heater element 26a in two paths, so that the amount of current flowing through the folded portion 262 is the conventional amount. It can be further reduced. As a result, although the shape is more complicated than in the case of the first embodiment, current concentration at the folded portion 262 of the heater element 26a can be significantly suppressed during energization, and the heater life can be extended. Then, the frequency of replacing the member of the heater 26 can be reduced, and the cost and downtime of the semiconductor manufacturing apparatus can be reduced.

  In the present embodiment, the current in the heater element 26a has two paths. However, by forming slits as appropriate, three or more paths having the same distance through which the current flows can be separated. The heater element 26a is not limited to a disk shape. Note that the effect obtained by dividing the current path as in this embodiment is the same even when the folded portion 262 is not provided.

<Third Embodiment>
FIG. 7 is a top view showing the heater element 36a constituting the resistance heater of the present embodiment. The difference from the second embodiment is that, in the heat generating part 360, in the central part of the heater element 36a where the potential at the position separated by the slit is substantially the same, in the vicinity of the connection position with the heater electrode parts 16b and 16c, etc. The point is that the meandering slit 361 is not provided.

  In addition, the heater element 36a has three pin holes 364 that receive the wafer w introduced into the reaction chamber 10 and serve as passages for push-up pins (not shown) placed on the susceptor 13, thereby reducing the heat generation area. In order to suppress this, it is formed so as to be connected to the slit 361. Further, a current arc portion 363 a is formed in the adjacent linear slit 363 so that the conductive portion is not narrowed by the pin hole 364.

  According to the present embodiment, the serpentine slit 361 is divided at the center of the equipotential heater element 36a. For this reason, the total area of the meandering slit 361 can be kept small without affecting the current distribution, and the strength of the heater 36 as a whole can be improved compared to the case of the second embodiment shown in FIG. Can do.

  FIG. 8 is a view showing a heater element 16a similar to that of the first embodiment. At the outer periphery B of the peripheral portion A of the folded portion 162, the amount of heat generated at A is about 55%, and the amount of heat generated at C separated from the folded portion 162 is about 13% of the amount of heat generated at A. Furthermore, the amount of heat generated in D, where current is difficult to flow, is about 6% of the amount of heat generated in A, indicating that there is variation in the amount of heat generated in the surface.

  On the other hand, in the heater element 36a of the present embodiment shown in FIG. 9, the heat generation amount at the peripheral edge A ′ of the folded portion 362 is reduced to about 75% with respect to the heat generation amount in A of FIG. In addition, the heat generation amount at A ′ is about 60% for B ′ and about 30% for C ′, and the area where the current hardly flows like D ′ becomes small. Thus, it can be seen that by providing the serpentine slit 361, the electric field concentration is further suppressed and the in-plane distribution is improved.

<Fourth Embodiment>
FIG. 10 is a top view showing the heater element 46a constituting the resistance heater according to the present embodiment. As shown in FIG. 10, the heater element 46 a according to the present embodiment is different in that the linear slit 463 is chamfered on all of the end portions on the outer peripheral side of the heat generating portion 460. Note that chamfering may be performed not only on the slit end but also on all corners of the heat generating portion 460. As described above, by chamfering the end portion where current does not easily flow, the influence on the temperature distribution can be suppressed and the heater element 46a can be prevented from being damaged.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

10 ... reaction chamber,
11a, 11b ... gas supply ports,
12 ... Rectifying plate,
13 ... susceptor,
14 ... Rotating member,
15 ... Rotation drive control mechanism,
16 ... heater,
16a, 26a, 36a, 46a ... heater element,
16b, 16c ... heater electrode part,
17a, 17b ... booth bar,
18a, 18b ... electrodes,
19a, 19b ... radiation thermometer,
20 ... temperature control mechanism,
160, 260, 360, 460 ... heating unit,
261,361 ... serpentine slits 163, 263, 363, 463 ... linear slits,
162, 262, 362... Folded portion.

Claims (6)

A sheet-like heat generating portion, one end on the outer periphery of the heat generating portion, the other end in the heat generating portion and a linear slit formed in a straight line, and an opening formed continuously to the other end, A heater element that has an opening width larger than the slit width of the linear slit, and generates heat when energized;
A pair of electrodes connected to a predetermined surface of the heater element, to which a voltage is applied when energizing the heater element;
A heater comprising:   2. The heater element according to claim 1, further comprising a serpentine slit formed in a serpentine shape in the heat generating portion in an arrangement in which a current flowing from the pair of electrodes into the heat generating portion is equally divided. heater.   The heater according to claim 2, wherein the serpentine slit is divided at a central portion of the heat generating portion. The linear slit bends in a direction along a concentric circle on the outer edge of the heat generating portion, with an end between a predetermined distance from the other end,
The heater according to any one of claims 1 to 3, wherein the folded portion is arranged on the concentric circle so as to be shifted from the center line of the main body portion by a predetermined angle.   The heater according to any one of claims 1 to 4, wherein the linear slit is chamfered at the one end. A reaction chamber into which the wafer is introduced;
A gas supply mechanism for supplying a process gas to the reaction chamber;
A gas exhaust mechanism for exhausting gas from the reaction chamber;
A wafer support member on which the wafer is placed;
A rotating member connected to the outer periphery of the wafer support member and rotating the wafer;
A rotation drive control mechanism that is connected to the rotation member and controls the rotation drive of the rotation member;
A sheet-like heat generating portion, a linear slit having one end disposed on the outer periphery of the heat generating portion, the other end disposed in the folded portion of the heat generating portion, and a linear opening, and an opening continuous to the other end A heater element that is formed and has an opening width larger than the width of the linear slit, and that is connected to a predetermined surface of the heater element that is heated by energization, and a voltage is applied when the heater element is energized A heater having a pair of electrodes;
A semiconductor manufacturing apparatus comprising: