JP2006245202A - Heat treatment apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide, in lower cost, a heat treatment apparatus for preventing the formation of a part of a process tube heated excessively higher than an equally heated region by surely controlling a temperature in the process tube. <P>SOLUTION: Temperatures of three points including both edges of an equally heated region Eb and the central area of the process tube 11 are detected by thermocouples 17b, 17d and 17c and temperatures of regions Ea, Ec are detected by thermocouples 17a, 17e using profile thermocouples 17 of five-point type thermocouples. A temperature controller 20 controls, in an optimum state, a temperature in the process tube 11 not to allow a temperature in each region Ea, Ec to exceed the temperature of the equally heated region Eb, by covering thermal losses at the deeper area 11a of a furnace and at the entrance 11b of the furnace by individually controlling temperatures of heaters 15a to 15c based on temperature detection results of spike thermocouples 16a to 16c, and by correcting the relevant temperature control based on temperature detection result of thermocouples 17a to 17e forming the profile thermocouple 17. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a heat treatment apparatus, and more particularly to an apparatus for controlling the temperature in a process tube in a wafer heat treatment apparatus used in semiconductor manufacturing.

In semiconductor manufacturing, various heat treatment apparatuses are used to heat-treat semiconductor wafers in an appropriate gas atmosphere.
As such a heat treatment apparatus, for example, a thermal diffusion apparatus (thermal diffusion furnace) that thermally diffuses impurities on the wafer surface, a thermal oxidation apparatus that forms an oxide film of silicon dioxide on the surface of a silicon wafer using a thermal oxidation method, A reflow device that melts the silicate glass interlayer insulation film to flatten the wafer surface, an annealing device that activates impurities on the wafer surface and recovers damage to the semiconductor crystals, and a CVD (Chemical Vapor Deposition) method on the wafer. There are a CVD apparatus for forming various thin films, an ashing apparatus for removing a photoresist film on the wafer surface, and the like.
In general, the same heat treatment apparatus is used for thermal diffusion, thermal oxidation, reflow, and annealing.

  In the heat treatment apparatus, a certain region in the process tube (core tube) is set as a soaking region (soaking zone) having a constant temperature. And by controlling the temperature of the heater for heating the outer peripheral wall surface of the process tube to raise the temperature inside the process tube, the temperature is controlled to be constant over the entire length of the soaking area (soaking length). By arranging a boat on which the semiconductor wafer is mounted in the soaking area, an optimum heat treatment is performed on the semiconductor wafer.

That is, a profile thermocouple (inner thermocouple) is installed inside the process tube, and a spike thermocouple (outer thermocouple) for detecting the temperature of the heater is installed outside the process tube.
Then, the temperature control of the heater is mainly performed based on the temperature detection result of the spike thermocouple, and the temperature control is corrected based on the temperature detection result of the profile thermocouple. The disadvantage of not being able to accurately detect the temperature in the process tube is compensated.

In a horizontal heat treatment apparatus using a horizontal (horizontal) process tube, a three-point thermocouple in which three thermocouples having different lengths are mounted in a quartz protective tube is used as a profile thermocouple. And the temperature of the three places of the both ends of the soaking | uniform-heating area | region in a process tube and a center part is each detected with three thermocouples, The detection result is by the external measuring device (profiler) connected to the profile thermocouple. Recorded and displayed.
In the horizontal heat treatment apparatus, three one-point thermocouples are used as spike thermocouples. And the temperature of the outer peripheral wall surface of the process tube corresponding to three places of the both ends of the heat equalization area | region in a process tube and a center part was each detected with three thermocouples, and the detection result was connected to the spike thermocouple. Recorded and displayed by an external measuring device.

  However, in the conventional technology, the temperature detection locations are limited to three locations inside and outside the process tube, so the temperature in the intermediate region of the temperature detection location cannot be detected, and the temperature of the soaking region in the process tube As a result, it is difficult to maintain the entire soaking region at a desired temperature.

Therefore, one thermocouple installed in the process tube, a transfer member installed outside the process tube and connected to one end of the thermocouple, a guide rail for guiding the linear movement of the transfer member, A drive unit that linearly moves the transfer member so that the thermocouple moves at a constant speed from one end to the other end of the process tube, while moving the thermocouple from one end to the other end of the process tube. A technique has been proposed in which the process temperature is detected over the entire length in the process tube (see Patent Document 1).
Japanese Patent Laid-Open No. 10-19687 (pages 2 to 4 and FIGS. 1 to 4)

  The technique of Patent Document 1 requires a transfer member, a guide rail, and a drive unit, so that there is a problem that the entire apparatus becomes large and costs increase.

  By the way, in patent document 1, the 1st area | region ("B" area | region) from the soaking area to the furnace back (closed end part) where the process tube was closed, and the furnace port where the process tube was opened from the soaking area. Since heat loss occurs in the second region (“A” region) up to (open end), it is described that it is necessary to form a heat block by raising the temperature of each region considerably compared to the soaking region. Has been.

However, if the temperature of each region is high, when the semiconductor wafer is carried into and out of the process tube, the semiconductor wafer is exposed to a high temperature when the semiconductor wafer passes through the region, so that there are crystal defects in the semiconductor wafer. As a result, the number of defective semiconductor wafers increases, yield decreases, and productivity decreases.
Therefore, it is required to control the temperature in the process tube so that the temperature in each region does not greatly exceed the temperature in the soaking region.
Not only the horizontal heat treatment apparatus but also the vertical heat treatment apparatus using a vertical (vertical) process tube has the same problems and requirements as described above.

  The present invention has been made to solve the above-mentioned problems and satisfy the above-mentioned requirements. The purpose of the present invention is to reliably control the temperature in the process tube to produce a part that greatly exceeds the temperature of the soaking area. It is an object of the present invention to provide a low-cost heat treatment apparatus that can reduce defective products of semiconductor wafers, improve yield, and improve productivity.

The invention described in claim 1
A heat treatment apparatus that accommodates a wafer used in semiconductor manufacturing in a process tube, supplies an appropriate gas into the process tube, heats the wafer in the gas atmosphere, and performs heat treatment,
The process tube has a closed closed end and an open open end;
A gas introduction pipe for introducing gas into the process tube is connected to the closed end,
The open end is opened with a discharge port for exhausting the gas in the process tube, and a closing lid for closing the open end is attached,
In the process tube, there are a soaking area controlled at a constant temperature, a first area from the soaking area to the closed end, and a second area from the soaking area to the open end. Set,
A heater for heating the outer peripheral wall surface of the process tube;
First temperature detecting means for detecting the temperature of the outer peripheral wall surface of the process tube;
Second temperature detecting means for detecting the temperature in the process tube;
Temperature control means for performing temperature control of the heater based on the temperature detection result by the first temperature detection means, and correcting the temperature control based on the temperature detection result by the second temperature detection means,
The second temperature detecting means includes
A first detector that is arranged in the first region and detects the temperature of the arrangement location;
A second detection unit that is arranged at a boundary portion between the first region and the soaking region and detects the temperature of the arrangement part;
A third detection unit that is arranged in the soaking area and detects the temperature of the arrangement part;
A fourth detector that is arranged at a boundary portion between the soaking area and the second area and detects the temperature of the arrangement place;
It has a 5th detection part arrange | positioned in the said 2nd area | region, and detects the temperature of the said arrangement | positioning location, It is a technical feature.

The invention described in claim 2
A heat treatment apparatus that accommodates a wafer used in semiconductor manufacturing in a process tube, supplies an appropriate gas into the process tube, heats the wafer in the gas atmosphere, and performs heat treatment,
The process tube has a closed closed end and an open open end;
A gas introduction pipe for introducing gas into the process tube is connected to the closed end,
The open end is opened with a discharge port for exhausting the gas in the process tube, and a closing lid for closing the open end is attached,
In the process tube, there are a soaking area controlled at a constant temperature, a first area from the soaking area to the closed end, and a second area from the soaking area to the open end. Set,
A heater for heating the outer peripheral wall surface of the process tube;
First temperature detecting means for detecting the temperature of the outer peripheral wall surface of the process tube;
Second temperature detecting means for detecting the temperature in the process tube;
Temperature control means for performing temperature control of the heater based on the temperature detection result by the first temperature detection means, and correcting the temperature control based on the temperature detection result by the second temperature detection means,
The second temperature detecting means includes
A first detection unit that is arranged inside the soaking area by a first predetermined distance from a boundary portion between the first area and the soaking area, and detects the temperature of the arrangement location;
A second detection unit that is arranged in the soaking area and detects the temperature of the arrangement part;
It has a third detection unit that is arranged inside the soaking area by a second predetermined distance from a boundary portion between the soaking area and the second area and detects the temperature of the arrangement location. .

The invention according to claim 3
A heat treatment apparatus that accommodates a wafer used in semiconductor manufacturing in a process tube, supplies an appropriate gas into the process tube, heats the wafer in the gas atmosphere, and performs heat treatment,
The process tube has a closed closed end and an open open end;
A gas introduction pipe for introducing gas into the process tube is connected to the closed end,
The open end is opened with a discharge port for exhausting the gas in the process tube, and a closing lid for closing the open end is attached,
In the process tube, there are a soaking area controlled at a constant temperature, a first area from the soaking area to the closed end, and a second area from the soaking area to the open end. Set,
A heater for heating the outer peripheral wall surface of the process tube;
First temperature detecting means for detecting the temperature of the outer peripheral wall surface of the process tube;
Second temperature detecting means and third temperature detecting means for detecting the temperature in the process tube;
The temperature of the heater is controlled based on the temperature detection result by the first temperature detection means, and after the temperature control is corrected based on the temperature detection result by the second temperature detection means, the temperature by the third temperature detection means Temperature control means for correcting the correction result again based on the detection result,
The second temperature detecting means includes
A first detection unit that is arranged at a boundary portion between the first region and the soaking region and detects the temperature of the arrangement part;
A second detection unit that is arranged in the soaking area and detects the temperature of the arrangement part;
A third detection unit that is arranged at a boundary portion between the soaking area and the second area and detects the temperature of the arrangement part;
The third temperature detecting means includes
A technical feature is that the temperature is detected over the entire length of the process tube while being moved from the open end to the closed end.

The invention according to claim 4
In the heat processing apparatus of any one of Claims 1-3,
The heater is
A first heater for heating an outer peripheral wall surface of the process tube corresponding to an outer portion of the first region;
A second heater for heating an outer peripheral wall surface of the process tube corresponding to an outer portion of the soaking area;
A third heater for heating the outer peripheral wall surface of the process tube corresponding to the outer portion of the second region,
The first temperature detecting means includes
A first detector for detecting a temperature of an outer peripheral wall surface of the process tube corresponding to a boundary portion between the first region and the soaking region;
A second detector for detecting the temperature of the outer peripheral wall surface of the process tube corresponding to the soaking area;
A third detection unit that detects a temperature of an outer peripheral wall surface of the process tube corresponding to a boundary portion between the soaking area and the second area;
The temperature control means is technically characterized by performing individual temperature control for each of the first to third heaters.

(Claim 1: corresponds to the first embodiment)
According to the first aspect of the present invention, the following actions and effects can be obtained.

(1-1)
The first temperature detecting means is installed outside the process tube to detect the temperature of the outer peripheral wall surface, and cannot directly detect the temperature in the process tube. Therefore, the temperature detection result of the first temperature detecting means includes an error from the actual temperature in the process tube.
Therefore, the temperature in the process tube cannot be accurately controlled only by controlling the temperature of the heater based on the temperature detection result of the first temperature detection means.

Therefore, second temperature detection means (first to fifth detection units) for directly detecting the temperature in the process tube is provided.
The temperature control unit corrects the temperature control of the heater based on the temperature detection result of the first temperature detection unit based on the temperature detection result of the second temperature detection unit.
As a result, the temperature detection error of the first temperature detecting means is compensated, and it is possible to reliably perform control for keeping the soaking area in the process tube at a desired constant temperature over its entire length (soaking length). .

(1-2)
In order to use the heat treatment apparatus of the invention of claim 1, first, as in (1-1), the temperature detection by the first temperature detection means and the temperature detection by the second temperature detection means are used in combination. The temperature control of the heater by the control means is set optimally.
When the temperature detection by the second temperature detection means is completed, first, the respective detection parts of the second temperature detection means are pulled out from the process tube, then the closing lid is removed, and then the opened open end side Then, a boat loaded with semiconductor wafers is loaded into the process tube, and then the open end is closed with a shutter.

In this state, while supplying an appropriate gas from the gas introduction pipe into the process tube, the outer peripheral wall surface of the process tube is heated using a heater, and the temperature inside the process tube is raised, whereby the semiconductor wafer is formed in a gas atmosphere. Heat and heat treatment.
At this time, the temperature control of the heater is optimized by the temperature control means, and the soaking area is at a constant temperature. Therefore, if a boat equipped with semiconductor wafers is placed in the soaking area, the optimum heat treatment for the semiconductor wafer is performed. It can be performed.

(1-3)
In the prior art, a three-point type thermocouple in which three thermocouples are mounted in a protective tube is used as each detection unit of the second temperature detection means, and both end portions and a central portion of the soaking area in the process tube are used. Three temperatures were detected by each thermocouple.
In the conventional technique, the temperature control means performs temperature control of the heater based on the temperature detection result of the first temperature detection means, and based on the temperature detection result of each thermocouple constituting the second temperature detection means. The temperature control was corrected.

Heat loss occurs at the closed end and the open end of the process tube because heat dissipation is greater than at the center in the longitudinal direction of the process tube.
Therefore, in the prior art, the temperature control means tries to cover the heat loss of the closed end and the open end, and controls the temperature of the closed end and the open end to be excessively higher than the center of the process tube. Had gone.
As a result, in the conventional technique, the temperature of the first region and the second region is considerably higher than that of the soaking region, and the heat is formed in the first region and the second region. It was.

However, if the temperature of the first region and the second region is high, when the semiconductor wafer is carried into and out of the process tube, the semiconductor wafer is exposed to a high temperature when the semiconductor wafer passes through the first region and the second region. Therefore, crystal defects are generated in the semiconductor wafer, the number of defective semiconductor wafers increases, the yield deteriorates, and the productivity decreases.
On the other hand, in the first aspect of the invention, the second temperature detecting means having the first to fifth detecting portions is used, and the temperatures at the two ends of the soaking area in the process tube and the central portion are set to the second and second temperatures. While detecting by the 4th, 3rd detection part, respectively, the temperature of the 1st, 2nd area | region is each detected by the 1st, 5th detection part.
And a temperature control means performs temperature control of a heater based on the temperature detection result of a 1st temperature detection means, and correct | amends the said temperature control based on the temperature detection result of each detection part which comprises a 2nd temperature detection means. .

Therefore, in the first aspect of the invention, the temperature control means can control the temperature of the closed end and the open end to be moderately higher than that of the central portion of the process tube. In addition to covering the heat loss at the end, the temperature in the process tube can be optimally controlled so that the temperature in the first region and the second region does not greatly exceed the temperature in the soaking region.
As a result, in the first aspect of the present invention, the temperature of the first to fifth detecting portions of the second temperature detecting means is substantially uniform, and the temperature gradually increases from the first detecting portion to the closed end. In addition, the temperature gradually decreases from the location where the fifth detector is disposed to the open end, and no heat block is formed in the first region and the second region.

Therefore, according to the first aspect of the present invention, when the semiconductor wafer is carried into and out of the process tube, the semiconductor wafer is not exposed to a high temperature when the semiconductor wafer passes through the first region and the second region. Since no crystal defects occur in the semiconductor wafer, defective products of the semiconductor wafer can be reduced, yield can be improved, and productivity can be improved.
For the locations of the first detection unit and the fifth detection unit in the first region and the second region, an optimum value was experimentally found by cut-and-try so as to obtain the above-mentioned action and effect sufficiently. Can be set.

(1-4)
According to the invention of claim 1, since it is only necessary to have the second temperature detecting means having the first to fifth detectors, the entire apparatus can be implemented at a low cost compared to the technique of Patent Document 1. it can.

(Claim 2: corresponds to the second embodiment)
According to the invention of claim 2, in addition to the same actions and effects as the above (1-1) and (1-2) of the invention of claim 1, the following actions and effects can be obtained.

(2-1)
As described in (1-3) of the invention of claim 1, in the prior art, as each detection part of the second temperature detection means, a three-point type thermoelectric device in which three thermocouples are mounted in a protective tube. Each pair of thermocouples was used to detect temperatures at both ends and the center of the soaking area in the process tube.
Heat loss occurs at the closed end and the open end of the process tube because heat dissipation is greater than at the center in the longitudinal direction of the process tube.
Therefore, the temperature at both ends of the soaking area in the process tube (the boundary portion between the soaking area and the first and second areas) tends to be slightly lower than the temperature at the center of the soaking area.

Therefore, in the prior art, the temperature control means tries to increase the temperature at both ends of the soaking area in the process tube (the boundary portion between the soaking area and the first and second areas). Compared to the above, the temperature of the closed end and the open end is controlled to be excessively high.
As a result, in the conventional technique, the temperature of the first region and the second region is considerably higher than that of the soaking region, and the heat is formed in the first region and the second region. It was.

On the other hand, in the second aspect of the invention, the second temperature detecting means having the first to third detection units is used, and the temperature of the central portion of the soaking area in the process tube is detected by the second detection unit. Is the same as the conventional technology.
However, in the invention of claim 2, the portion of the portion located inside the soaking area by the first and second predetermined distances from both ends of the soaking area (the boundary portion between the soaking area and the first and second areas). It differs from the prior art in that the temperatures are detected by the first and third detectors, respectively.

The portion located inside the soaking area by the first and second predetermined distances from both ends of the soaking area (the boundary between the soaking area and the first and second areas) is more than the both ends of the soaking area. Since it is close to the center of the soaking area, the temperature of the part is slightly higher than the temperature at the boundary between each soaking area and the first and second areas, and is almost the same as the temperature of the center of the soaking area. Be the same.
Therefore, in the invention of claim 2, the temperature control means is provided inside the soaking area by the first and second predetermined distances from both ends of the soaking area (the boundary portion between the soaking area and the first and second areas). Since there is no need to increase the temperature of the portion located at the center of the process tube, the temperature of the closed end and the open end is not excessively increased compared to the central portion of the process tube.
As a result, in the invention of claim 2, the temperature in the process tube is optimally controlled so that the temperature of the first region and the second region does not greatly exceed the temperature of the soaking region, and the first region and the second region Heat block is not formed.

Therefore, according to the invention of claim 2, as in the case of (1-3) of the invention of claim 1, the semiconductor wafer is not exposed to a high temperature when the semiconductor wafer passes through the first region and the second region. The number of defective semiconductor wafers can be reduced, yield can be improved, and productivity can be improved.
In addition, about the arrangement | positioning location (namely, 1st, 2nd predetermined distance) of a 1st, 3rd detection part, optimal value is experimentally cut and tried so that the said effect | action and effect may fully be acquired. Find and set.
For example, when the length (soaking length) between both ends of the soaking area (the boundary portion between the soaking area and the first and second areas) is 80 cm, the first and second predetermined distances are each 5 cm. Should be set.

(2-2)
According to the second aspect of the present invention, since it is only necessary to have the second temperature detection means having the first to third detection parts, the second temperature detection means having the first to fifth detection parts is provided. Compared to the present invention, the present invention can be implemented at a lower cost.

(Claim 3: corresponds to the third embodiment)
According to the invention of claim 3, in addition to the same actions and effects as the above (1-1) of the invention of claim 1, the following actions and effects can be obtained.

(3-1)
In order to use the heat treatment apparatus of the invention of claim 3, first, each detection part of the second temperature detection means is inserted into the process tube, and the three ends of the heat equalizing region in the process tube, that is, the three parts at the center part. The temperatures are detected by the first to third detection units, respectively.
Then, when the temperature detection by the second temperature detection means is completed, first, each detection unit of the second temperature detection means is pulled out from the process tube.

Subsequently, the third temperature detection means is inserted into the process tube, and the operator manually pushes the third temperature detection means into the process tube, so that each detection part of the third temperature detection means is opened from the open end side. The temperature over the entire length in the process tube is detected by the third temperature detecting means while gradually moving linearly toward the closed end.
Then, the temperature detection by the first temperature detection means and the temperature detection by the second temperature detection means and the third temperature detection means are used together to optimally set the temperature control of the heater by the temperature control means.

Thus, when temperature detection by each detection part of the 3rd temperature detection means is completed, first, each detection part of the 3rd temperature detection means is pulled out from the inside of a process tube, and then a closure lid is removed, and it opens continuously. A boat loaded with semiconductor wafers is loaded into the process tube from the opened end side, and then the open end is closed with a shutter.
Subsequent operations are the same as in (1-1) of the invention of claim 1, and the same actions and effects as in (1-1) are obtained in the invention of claim 3.

(3-2)
In the invention of claim 3, using the second temperature detection means having the first to third detection units, the point of detecting the temperature at the three ends of the both ends and the center of the soaking area in the process tube, It is the same as the conventional technology.
However, the invention of claim 3 is different from the prior art in that the temperature detection by the third temperature detection means is performed in addition to the temperature detection by each detection part of the second temperature detection means.

  Since the third temperature detection means detects the temperature while moving over the entire length in the process tube, other than the arrangement locations of the respective detection portions of the second temperature detection means (three locations at both ends and the central portion of the soaking area) The actual temperature can also be detected for these locations (arbitrary locations in the first region and the second region, and arbitrary locations between both ends and the central portion of the soaking region).

And the temperature control means performs the temperature control of the heater based on the temperature detection result of the first temperature detection means, and after correcting the temperature control based on the temperature detection result of each detection unit of the second temperature detection means, The correction result is corrected again based on the temperature detection result of the third temperature detection means.
Therefore, according to the invention of claim 3, the temperature in the process tube is detected by detecting the temperature at an arbitrary location in the process tube that cannot be detected by each detection unit of the second temperature detection unit by the third temperature detection unit. It can be controlled optimally.

As a result, in the invention of claim 3, the temperature in the process tube except for the vicinity of the closed end and the open end becomes substantially uniform, and no heat block is formed in the first region and the second region.
Therefore, according to the invention of claim 3, as in the case of (1-3) of the invention of claim 1, the semiconductor wafer is not exposed to a high temperature when the semiconductor wafer passes through the first region and the second region. The number of defective semiconductor wafers can be reduced, yield can be improved, and productivity can be improved.

(3-3)
According to the invention of claim 3, since the operator manually operates the third temperature detecting means to move the inside of the process tube, the entire apparatus is provided with a complicated mechanism (transfer member, guide rail, drive unit). Compared with the technique of Patent Document 1 which is a large scale, it can be implemented at a much lower cost.

(Claim 4)
According to the invention of claim 4, the first to third heaters are provided, and the temperature control means performs individual temperature control for each of the first to third heaters. The temperature of the region and the second region can be optimally controlled.
In addition, since the first temperature detection unit includes the first to third detection units, the temperature control unit performs the temperature control of the first to third heaters based on the temperature detection result by the first temperature detection unit. Control can be optimized.

(Explanation of terms)
The correspondence between the constituent elements described in [Means for Solving the Problems] described above and the constituent members described in [Best Mode for Carrying Out the Invention] described below is as follows. .

The “closed end” corresponds to the furnace interior 11a.
The “open end” corresponds to the furnace port 11b.
The “first temperature detecting means” corresponds to the spike thermocouples 16 a to 16 c and the measuring device 18.
The “second temperature detecting means” corresponds to the profile thermocouples 17, 31, 41 and the measuring device 19.
The “temperature control means” corresponds to the temperature control device 20.

The “first detector” of the “second temperature detector” in claim 1 corresponds to the thermocouple 17a.
The “second detection part” of the “second temperature detection means” in claim 1 corresponds to the thermocouple 17b.
The “third detection portion” of the “second temperature detection means” in claim 1 corresponds to the thermocouple 17c.
The “fourth detector” of the “second temperature detector” in claim 1 corresponds to the thermocouple 17d.
The “fifth detector” of the “second temperature detector” in claim 1 corresponds to the thermocouple 17e.

The “first detector” of the “second temperature detector” in claim 2 corresponds to the thermocouple 31a.
The “second detector” of the “second temperature detector” in claim 2 corresponds to the thermocouple 31b.
The “third detection portion” of the “second temperature detection means” in claim 2 corresponds to the thermocouple 31c.

The “first detector” of the “second temperature detector” in claim 3 corresponds to the thermocouple 41a.
The “second detector” of the “second temperature detector” in claim 3 corresponds to the thermocouple 41b.
The “third detection portion” of the “second temperature detection means” in claim 3 corresponds to the thermocouple 41c.
The “third temperature detection means” corresponds to the profile thermocouple 42 (thermocouple 42 a) and the measuring device 19.

The “first heater” corresponds to the heater 15a.
The “second heater” corresponds to the heater 15b.
The “third heater” corresponds to the heater 15c.
The “first detection unit” of the “first temperature detection unit” corresponds to the spike thermocouple 16a.
The “second detection unit” of the “first temperature detection means” corresponds to the spike thermocouple 16b.
The “third detection unit” of the “first temperature detection unit” corresponds to the spike thermocouple 16c.

  Hereinafter, embodiments embodying the present invention will be described with reference to the drawings. In each embodiment, the same constituent members are denoted by the same reference numerals, and redundant description of the same content is omitted.

(First embodiment)
FIG. 1 is a schematic longitudinal sectional view of a horizontal heat treatment apparatus 10 in the first embodiment.
A horizontal (horizontal) heat treatment apparatus 10 includes a horizontal (horizontal) process tube (core tube, reaction tube, heat treatment furnace) 11, a gas introduction tube 12, an exhaust port 13, a closing lid 14, heaters 15a to 15c, and spikes. It consists of thermocouples (outer thermocouples) 16a to 16c, profile thermocouples (inner thermocouples) 17, measuring devices (profilers) 18, 19, a temperature control device 20, and the like.

The process tube 11 made of quartz or silicon carbide and having a substantially cylindrical shape is disposed horizontally, one end is closed to form a furnace back (closed end) 11a, and the other end is opened to open a furnace port (open). (End part) 11b is formed.
A gas introduction pipe 12 for supplying a reaction gas into the process tube 11 is connected to the center of the furnace interior 11a.

A discharge port 11c is opened in the side wall of the lower portion of the furnace port 11b, and an exhaust port 13 for exhausting the gas in the process tube 11 is connected to the discharge port 11c.
Further, a closing lid 14 for closing the furnace port 11b is attached to the furnace port 11b. The closing lid 14 is formed of the same material as the process tube 11 or a material having a thermal expansion coefficient close to that of the process tube 11.

A soaking area (soaking section) Eb is set at a substantially central portion in the longitudinal direction in the process tube 11. The length in the longitudinal direction of the soaking area Eb is called “soaking length”.
And, from the soaking area Eb in the process tube 11 to the furnace depth 11a is set to the first area (first section) Ea, and from the soaking area Eb to the furnace port 11b in the process tube 11 is the second area (the first zone). 2 sections) Ec.
That is, the inside of the process tube 11 is divided into three regions (a first region Ea, a soaking region Eb, and a second region Ec) in the longitudinal direction from the furnace back 11a side to the furnace port 11b side.

The process tube 11 is inserted into the coil-type heaters 15a to 15c, and the outer peripheral wall surface of the process tube 11 is surrounded by the heaters 15a to 15c.
The heater 15a is disposed so as to surround the outer peripheral wall surface of the process tube 11 corresponding to the outer portion of the first region Ea.
The heater 15b is arrange | positioned so that the outer peripheral wall surface of the process tube 11 applicable to the outer side part of the soaking | uniform-heating area | region Eb may be enclosed.
The heater 15c is disposed so as to surround the outer peripheral wall surface of the process tube 11 corresponding to the outer portion of the second region Ec.

Each of the spike thermocouples 16a to 16c is composed of a one-point type thermocouple.
The spike thermocouple 16a is arranged between the heaters 15a and 15b, and detects (detects) the temperature of the outer peripheral wall surface of the process tube 11 at the arrangement location.
The spike thermocouple 16b is disposed at the center portion in the longitudinal direction of each heater 15b, and detects (detects) the temperature of the outer peripheral wall surface of the process tube 11 at the disposed position.
The spike thermocouple 16c is arranged between the heaters 15b and 15c, and detects (detects) the temperature of the outer peripheral wall surface of the process tube 11 at the arrangement location.
That is, the spike thermocouple 16a detects the temperature of the outer peripheral wall surface of the process tube 11 corresponding to the boundary portion between the first region Ea and the soaking region Eb (one end portion of the soaking region Eb), and the spike thermocouple 16b The temperature of the outer peripheral wall surface of the process tube 11 corresponding to the center in the longitudinal direction of the region Eb is detected, and the spike thermocouple 16c is located at the boundary portion between the soaking region Eb and the second region Ec (the other end of the soaking region Eb). The temperature of the outer peripheral wall surface of the corresponding process tube 11 is detected.

The profile thermocouple 17 is composed of a five-point thermocouple in which five thermocouples 17a to 17e having different lengths are mounted in a protective tube 17f made of quartz.
The profile thermocouple 17 is inserted into the process tube 11 from the distal end side through the insertion hole 14a opened in the closing lid 14.
And the temperature detection part formed in the front-end | tip part of the thermocouple 17a is arrange | positioned in the 1st area | region Ea, and detects (detects) the temperature in the process tube 11 in the arrangement | positioning location.
The temperature detection part formed in the front-end | tip part of the thermocouple 17b is arrange | positioned in the boundary part of 1st area | region Ea and soaking | uniform-heating area | region Eb, and detects (detects) the temperature in the process tube 11 in the arrangement | positioning location.
The temperature detection part formed in the front-end | tip part of the thermocouple 17c is arrange | positioned in the longitudinal direction center part of the soaking | uniform-heating area | region Eb, and detects (detects) the temperature in the process tube 11 in the arrangement | positioning location.
The temperature detection part formed in the front-end | tip part of the thermocouple 17d is arrange | positioned in the boundary part of soaking | uniform-heating area | region Eb and 2nd area | region Ec, and detects (detects) the temperature in the process tube 11 in the arrangement | positioning location.
The temperature detection part formed in the front-end | tip part of the thermocouple 17e is arrange | positioned in the 2nd area | region Ec, and detects the temperature in the process tube 11 in the arrangement | positioning location (detection).
That is, each thermocouple 17b, 17d detects the temperature at both ends of the soaking area Eb, and the thermocouple 17c detects the temperature at the longitudinal center of the soaking area Eb.

The measuring device 18 is connected to each of the spike thermocouples 16a to 16c, and automatically measures and records / displays the temperature detection result of each of the spike thermocouples 16a to 16c, and outputs the temperature detection result to the temperature control device 20. .
The measuring device 19 is connected to the profile thermocouple 17 and automatically measures (auto-profiles) the temperature detection results of the thermocouples 17a to 17e constituting the profile thermocouple 17 and records / displays the temperature detection results. Output to the temperature controller 20.

  The temperature control device 20 performs individual temperature control for each of the heaters 15 a to 15 c based on the temperature detection results of the spike thermocouples 16 a to 16 c input from the measurement device 18, and the profile thermocouple 17 input from the measurement device 19. The temperature control is corrected based on the temperature detection result of (thermocouples 17a to 17e).

[Operations and effects of the first embodiment]
According to the first embodiment, the following actions and effects can be obtained.

[1-1]
The spike thermocouples 16a to 16c are installed outside the process tube 11 to detect the temperature of the outer peripheral wall surface, and cannot detect the temperature inside the process tube 11 directly. For this reason, the temperature detection results of the spike thermocouples 16a to 16c include an error from the actual temperature in the process tube 11.
Therefore, the temperature in the process tube 11 cannot be accurately controlled only by controlling the temperatures of the heaters 15a to 15c based on the temperature detection results of the spike thermocouples 16a to 16c.

Therefore, a profile thermocouple 17 (thermocouples 17a to 17e) that directly detects the temperature in the process tube 11 is provided.
The temperature control device 20 corrects the temperature control of the heaters 15 a to 15 c based on the temperature detection results of the spike thermocouples 16 a to 16 c based on the temperature detection result of the profile thermocouple 17.
As a result, the temperature detection error of each of the spike thermocouples 16a to 16c is compensated, and the control for keeping the soaking area Eb in the process tube 11 at a desired constant temperature over its entire length (soaking length) is ensured. It can be carried out.

[1-2]
In order to use the horizontal heat treatment apparatus 10, first, as described in [1-1], the temperature detection by the spike thermocouples 16a to 16c and the temperature detection by the profile thermocouple 17 are used in combination. The temperature control of the heaters 15a to 15c is set optimally.
When the temperature detection by the profile thermocouple 17 is completed, the profile thermocouple 17 is first pulled out from the process tube 11, then the closing lid 14 is removed, and then the process tube 11 is opened from the opened furnace port 11 b side. A boat (not shown) loaded with semiconductor wafers is carried in, and then the furnace port 11b is closed with a shutter (not shown).

In this state, while supplying an appropriate gas from the gas introduction pipe 12 into the process tube 11, the outer peripheral wall surface of the process tube 11 is heated using the heaters 15 a to 15 c to raise the temperature inside the process tube 11. Then, heat treatment is performed by heating the semiconductor wafer in a gas atmosphere.
At this time, the temperature control of the heaters 15a to 15c is optimized by the temperature control device 20, and the soaking area Eb is at a constant temperature. Therefore, if a boat loaded with semiconductor wafers is placed in the soaking area Eb, The optimum heat treatment can be performed on the semiconductor wafer.

[1-3]
In the conventional technique, a three-point type thermocouple in which each thermocouple 17b to 17d is mounted in a protective tube 17f is used as a profile thermocouple, and 3 at both ends and the center of the soaking area Eb in the process tube 11 are used. The temperature of the location was detected by each thermocouple 17b, 17d, 17c.
In the conventional technique, the temperature control device 20 controls the temperature of each heater 15a to 15c based on the temperature detection result of each spike thermocouple 16a to 16c, and each thermocouple 17b to 17d constituting the profile thermocouple. The temperature control was corrected based on the temperature detection result.

FIG. 2 is a characteristic diagram showing a temperature distribution in the process tube 11 in the first embodiment.
Heat loss is generated at the furnace depth 11a and the furnace port 11b of the process tube 11 because heat dissipation is larger than that at the center in the longitudinal direction of the process tube 11.
Therefore, in the conventional technique, the temperature control device 20 performs control to increase the temperatures of the heaters 15a and 15c excessively as compared with the temperature of the heater 15b in an attempt to cover the heat loss of the furnace interior 11a and the furnace port 11b. It was.
As a result, in the conventional technique, as shown by the dotted line in FIG. 2, the temperature of the first region Ea and the second region Ec is considerably higher than that of the soaking region Eb, so Heat blocks were formed on Ea and Ec.

  However, if the temperatures of the regions Ea and Ec are high, the semiconductor wafer is exposed to a high temperature when the semiconductor wafer passes through the regions Ea and Ec when the semiconductor wafer is carried into and out of the process tube 11. Crystal defects are generated in the semiconductor wafer, the number of defective semiconductor wafers increases, the yield deteriorates, and the productivity decreases.

In contrast, in the first embodiment, as the profile thermocouple 17, a five-point thermocouple in which each thermocouple 17 a to 17 e is mounted in the protective tube 17 f is used, and both ends of the soaking area Eb in the process tube 11 are used. The thermocouples 17b, 17d, and 17c detect the temperatures of the three portions at the center and the center, respectively, and the temperatures of the regions Ea and Ec are detected by the thermocouples 17a and 17e, respectively.
And the temperature control apparatus 20 controls the temperature of each heater 15a-15c based on the temperature detection result of each spike thermocouple 16a-16c, and the temperature detection result of each thermocouple 17a-17e which comprises the profile thermocouple 17 The temperature control is corrected based on

Therefore, in the first embodiment, the temperature control device 20 can perform control to appropriately increase the temperatures of the heaters 15a and 15c as compared with the temperature of the heater 15b. After covering the heat loss, the temperature in the process tube 11 can be optimally controlled so that the temperature of each region Ea, Ec does not greatly exceed the temperature of the soaking region Eb.
As a result, in the first embodiment, as shown by the solid line in FIG. 2, the temperatures of the thermocouples 17a to 17e are substantially uniform, and the temperature gradually increases from the thermocouple 17a to the furnace back 11a. As the temperature decreases, the temperature gradually decreases from the location where the thermocouple 17e is disposed to the furnace port 11b, and no heat block is formed in each of the regions Ea and Ec.

Accordingly, when the semiconductor wafer is carried into and out of the process tube 11, the semiconductor wafer is not exposed to a high temperature when the semiconductor wafer passes through the regions Ea and Ec, and crystal defects do not occur in the semiconductor wafer. The number of defective semiconductor wafers can be reduced, yield can be improved, and productivity can be improved.
In addition, what is necessary is just to find and set an optimal value experimentally by cut and try about the arrangement | positioning location of each thermocouple 17a, 17e in each area | region Ea, Ec so that the said effect | action and effect may fully be acquired. .

[1-4]
According to the first embodiment, since it is only necessary to use a five-point thermocouple including the thermocouples 17a to 17e as the profile thermocouple 17, the cost of the entire apparatus is low compared to the technique of Patent Document 1. Can be implemented.

(Second Embodiment)
FIG. 3 is a schematic longitudinal sectional view of a horizontal heat treatment apparatus 30 in the second embodiment.
The horizontal heat treatment apparatus 30 includes a horizontal process tube 11, a gas introduction pipe 12, an exhaust port 13, a closing lid 14, heaters 15a to 15c, spike thermocouples 16a to 16c, measuring apparatuses 18 and 19, temperature control apparatus 20, and profile thermocouple. 31 or the like.

The horizontal heat treatment apparatus 30 is different from the horizontal heat treatment apparatus 10 of the first embodiment only in that the profile thermocouple 17 is replaced with a profile thermocouple 31.
The profile thermocouple 31 is composed of a three-point thermocouple in which three thermocouples 31a to 31c having different lengths are mounted in a protective tube 31d made of quartz.
The profile thermocouple 31 is inserted into the process tube 11 from the distal end side through the insertion hole 14a opened in the closing lid 14.

And the temperature detection part formed in the front-end | tip part of the thermocouple 31a is arrange | positioned inside the soaking | uniform-heating area | region Eb only predetermined distance La from the boundary part (alpha) of 1st area | region Ea and soaking | uniform-heating area | region Eb, (Part) The temperature in the process tube 11 at β is detected (detected).
The temperature detection part formed in the front-end | tip part of the thermocouple 31b is arrange | positioned in the longitudinal direction center part of the soaking | uniform-heating area | region Eb, and detects (detects) the temperature in the process tube 11 in the arrangement | positioning location.
The temperature detection part formed at the tip of the thermocouple 31c is arranged inside the soaking area Eb by a predetermined distance Lb from the boundary part γ between the soaking area Eb and the second area Ec. The temperature in the process tube 11 at δ is detected (detected).
That is, each of the thermocouples 31a and 31c detects the temperatures of the parts β and δ located inside the soaking area Eb by a predetermined distance La and Lb from both ends (boundary parts α and γ) of the soaking area Eb. The thermocouple 31b detects the temperature of the center portion in the longitudinal direction of the soaking area Eb.

The measuring device 19 is connected to the profile thermocouple 31, records and displays the temperature detection results of the thermocouples 31 a to 31 c constituting the profile thermocouple 31, and outputs the temperature detection results to the temperature control device 20.
The temperature control device 20 performs individual temperature control for each of the heaters 15 a to 15 c based on the temperature detection results of the spike thermocouples 16 a to 16 c input from the measurement device 18, and the profile thermocouple 31 input from the measurement device 19. The temperature control is corrected based on the temperature detection result of (thermocouples 31a to 31c).

[Operation and Effect of Second Embodiment]
According to the second embodiment, in addition to the same operations and effects as [1-1] and [1-2] of the first embodiment, the following operations and effects can be obtained.

[2-1]
As described in [1-3] of the first embodiment, in the conventional technique, a three-point thermocouple including the thermocouples 17b to 17d is used as a profile thermocouple, and soaking in the process tube 11 is performed. The temperatures at the three ends of the region Eb at both ends and the center were detected by the thermocouples 17b, 17d, and 17c, respectively.

FIG. 4 is a characteristic diagram showing a temperature distribution in the process tube 11 in the second embodiment.
Heat loss is generated at the furnace depth 11a and the furnace port 11b of the process tube 11 because heat dissipation is larger than that at the center in the longitudinal direction of the process tube 11.
Therefore, the temperature at both ends (boundary portions α, γ) of the soaking area Eb in the process tube 11 is slightly lower than the temperature at the center of the soaking area Eb.

Therefore, in the conventional technique, the temperature control device 20 tries to increase the temperature of both end portions (boundary portions α, γ) of the soaking area Eb in the process tube 11 as compared with the temperature of the heater 15b. Control was performed to raise the temperature of 15c excessively.
As a result, in the prior art, as shown by the dotted line in FIG. 4, the temperature of the first region Ea and the second region Ec is considerably higher than that of the soaking region Eb, so Heat blocks were formed on Ea and Ec.

In contrast, in the second embodiment, a three-point thermocouple including the thermocouples 31a to 31c is used as the profile thermocouple 31, and the temperature of the central portion of the soaking area Eb in the process tube 11 is set to the thermocouple 31b. The point detected by is the same as the conventional technique.
However, in the second embodiment, the temperatures of the parts β and δ located inside the soaking area Eb by a predetermined distance La and Lb from both ends (boundary parts α and γ) of the soaking area Eb are set to the thermocouples 31a, The point detected by 31c is different from the conventional technique.

Each part β, δ is closer to the center of the soaking area Eb than both ends (boundary parts α, γ) of the soaking area Eb. Therefore, the temperatures of the portions β and δ are slightly higher than the temperatures of the boundary portions α and γ, and are substantially the same as the temperature of the central portion of the soaking region Eb.
Therefore, in the second embodiment, the temperature control device 20 does not need to increase the temperature of the respective parts β and δ in the process tube 11, so that the temperatures of the heaters 15 a and 15 c are excessive compared to the temperature of the heater 15 b. Therefore, there is no need to perform control that makes it very high.
As a result, in the second embodiment, the temperature in the process tube 11 is optimally controlled so that the temperature of each region Ea, Ec does not greatly exceed the temperature of the soaking region Eb, as shown by the solid line in FIG. The heat blocks are not formed in the areas Ea and Ec.

Therefore, according to the second embodiment, as in [1-3] of the first embodiment, the semiconductor wafer is not exposed to a high temperature when the semiconductor wafer passes through the regions Ea and Ec. By reducing the number of defective products, the yield can be improved and the productivity can be improved.
Note that the positions of the portions β and δ (that is, the predetermined distances La and Lb) where the thermocouples 31a and 31c are arranged are cut and tried so that the above-described operation and effect can be sufficiently obtained. Find and set the optimal value experimentally.
For example, when the length (soaking length) between both end portions (boundary portions α, γ) of the soaking area Eb is 80 cm, the predetermined distances La and Lb may be set to 5 cm, respectively.

[2-2]
According to the second embodiment, since it is only necessary to use a three-point type thermocouple provided with each thermocouple 31a to 31c as the profile thermocouple 31, five points provided with each thermocouple 17a to 17e as the profile thermocouple 17 Compared to the first embodiment using a thermocouple, it can be implemented at a lower cost.

(Third embodiment)
5-7 is a schematic longitudinal cross-sectional view of the horizontal heat processing apparatus 40 in 3rd Embodiment.
The horizontal heat treatment apparatus 40 includes a horizontal process tube 11, a gas introduction pipe 12, an exhaust port 13, a closing lid 14, heaters 15 a to 15 c, spike thermocouples 16 a to 16 c, measuring apparatuses 18 and 19, a temperature controller 20, and a profile thermocouple. 41, 42 and the like.
The horizontal heat treatment apparatus 40 differs from the horizontal heat treatment apparatus 10 of the first embodiment only in that the profile thermocouple 17 is replaced with two profile thermocouples 41 and 42.

As shown in FIG. 5, the profile thermocouple 41 includes a three-point thermocouple in which three thermocouples 41a to 41c having different lengths are mounted in a quartz protective tube 41d.
The profile thermocouple 41 is inserted into the process tube 11 from the distal end side through the insertion hole 14a opened in the closing lid 14.
And the temperature detection part formed in the front-end | tip part of the thermocouple 41a is arrange | positioned in the boundary part of 1st area | region Ea and soaking | uniform-heating area | region Eb, and detects (detects) the temperature in the process tube 11 in the arrangement | positioning location.
The temperature detection part formed in the front-end | tip part of the thermocouple 41b is arrange | positioned in the longitudinal direction center part of the soaking | uniform-heating area | region Eb, and detects (detects) the temperature in the process tube 11 in the arrangement | positioning location.
The temperature detection part formed in the front-end | tip part of the thermocouple 41c is arrange | positioned in the boundary part of soaking | uniform-heating area | region Eb and 2nd area | region Ec, and detects (detects) the temperature in the process tube 11 in the arrangement | positioning location.
That is, each thermocouple 41a, 41c detects the temperature of both ends of the soaking area Eb, and the thermocouple 41b detects the temperature of the center part in the longitudinal direction of the soaking area Eb.

As shown in FIGS. 6 and 7, the profile thermocouple 42 is composed of a single-point thermocouple in which one thermocouple 42a is mounted in a quartz protective tube 42b.
The profile thermocouple 42 is inserted into the process tube 11 from the distal end side through the insertion hole 14 a opened in the closing lid 14.

The measuring device 19 is connected to the profile thermocouples 41 and 42 in a switched manner, and the temperature detection results of the thermocouples 41a to 41c and 42a constituting the profile thermocouples 41 and 42 are automatically measured (auto profile) and recorded. While displaying, the temperature detection result is output to the temperature control device 20.
The temperature control device 20 performs individual temperature control for each of the heaters 15 a to 15 c based on the temperature detection results of the spike thermocouples 16 a to 16 c input from the measurement device 18, and each profile thermocouple input from the measurement device 19. The temperature control is corrected based on the temperature detection results of 41 and 42 (thermocouples 41a to 41c and 42a).

[Operation and Effect of Third Embodiment]
According to the third embodiment, in addition to the same operations and effects as the above [1-1] of the first embodiment, the following operations and effects can be obtained.

[3-1]
In order to use the horizontal heat treatment apparatus 40, first, as shown in FIG. 5, the profile thermocouple 41 is connected to the measuring apparatus 19, and then the profile thermocouple 41 is inserted into the process tube 11. Temperatures at three locations, both ends and the center of the soaking area Eb, are detected by the thermocouples 41a, 41c, 41b, respectively.
When the temperature detection by the profile thermocouple 41 is completed, the profile thermocouple 41 is first pulled out from the process tube 11, and then the connection between the profile thermocouple 41 and the measuring device 19 is disconnected.

Subsequently, as shown in FIG. 6, the profile thermocouple 42 is connected to the measuring device 19, and then the profile thermocouple 42 is inserted into the process tube 11, so that the operator can insert the profile thermocouple 42 into the process tube 11. As shown in FIG. 7, the temperature over the entire length in the process tube 11 is changed by the thermocouple 42a while the profile thermocouple 42 is gradually linearly moved from the furnace port 11b side to the furnace back side 11a side as shown in FIG. Detect (detect).
Then, the temperature detection by the spike thermocouples 16a to 16c and the temperature detection by the profile thermocouples 41 and 42 are used in combination, and the temperature control of the heaters 15a to 15c by the temperature controller 20 is optimally set.

Thus, when the temperature detection by the profile thermocouple 42 is completed, first, the profile thermocouple 42 is pulled out from the process tube 11, then the closing lid 14 is removed, and then the process is started from the opened furnace port 11b side. A boat (not shown) loaded with semiconductor wafers is loaded into the tube 11, and then the furnace port 11 b is closed with a shutter (not shown).
The subsequent operation is the same as [1-1] in the first embodiment, and the same operation and effect as in [1-1] are obtained in the third embodiment.

[3-2]
In the third embodiment, with respect to the point of detecting the temperatures at the three ends of the soaking area Eb in the process tube 11 using the profile thermocouple 41 which is a three-point type thermocouple, Same as technology.
However, the third embodiment is different from the conventional technique in that the temperature is detected by the profile thermocouple 42 in addition to the temperature detection by the profile thermocouple 41.

FIG. 8 is a characteristic diagram showing a temperature distribution in the process tube 11 in the third embodiment.
Since the profile thermocouple 42 detects the temperature while moving over the entire length in the process tube 11, the locations of the thermocouples 41 a to 41 c constituting the profile thermocouple 41 (both ends and the center of the soaking area Eb) The actual temperature can also be detected at locations other than the above three locations (arbitrary locations within the respective regions Ea and Ec, and arbitrary locations between the both end portions and the central portion of the soaking region Eb).

And the temperature control apparatus 20 performs individual temperature control for each heater 15a-15c based on the temperature detection result of each spike thermocouple 16a-16c, and each thermocouple 41a-41c which comprises the profile thermocouple 41 is carried out. After correcting the temperature control based on the temperature detection result, the correction result is corrected again based on the temperature detection result of the thermocouple 42a constituting the profile thermocouple 42.
Therefore, according to the third embodiment, the process tube 11 is detected by detecting the temperature of an arbitrary location in the process tube 11 that cannot be detected by the thermocouples 41a to 41c constituting the profile thermocouple 41 by the profile thermocouple 42. The temperature inside can be optimally controlled.

As a result, in the third embodiment, as shown by the solid line in FIG. 8, the temperature in the process tube 11 except for the vicinity of the furnace depth 11a and the furnace port 11b becomes substantially uniform, and heat blocks are formed in the regions Ea and Ec. Not formed.
Therefore, according to the third embodiment, the semiconductor wafer is not exposed to a high temperature when the semiconductor wafer passes through the regions Ea and Ec, as in [1-3] of the first embodiment. By reducing the number of defective products, the yield can be improved and the productivity can be improved.

[3-3]
According to the third embodiment, since the operator manually operates the profile thermocouple 42 to move the inside of the process tube 11, the entire apparatus is large with a complicated mechanism (transfer member, guide rail, drive unit). Compared with the technique of Patent Document 1 that becomes, it can be implemented at a much lower cost.

[Another embodiment]
By the way, the present invention is not limited to the above-described embodiments, and may be embodied as follows. Even in this case, operations and effects equivalent to or more than those of the above-described embodiments can be obtained.

[1]
In each of the above embodiments, the thermocouples 16a to 16c, 17, 31, 41, and 42 are used for temperature detection. However, any type of thermocouple can be used as long as the temperature can be detected and converted into an electric signal. It may be replaced with a sensor.
Such sensors include a contact type and a non-contact type.
Examples of the contact type include a thermistor, a resistance thermometer, a thermal noise thermometer, and a semiconductor thermometer.
Examples of the non-contact type include a radiation thermometer and an optical pyrometer color thermometer (optical pyrometer).

[2]
Each of the above embodiments is applied to a horizontal (horizontal) heat treatment apparatus 10, 30, 40 using a horizontal (horizontal) process tube 11, but the present invention is not limited to a horizontal heat treatment apparatus, and is a vertical type. The present invention may be applied to a vertical (vertical) heat treatment apparatus using a (vertical) process tube.

[3]
Each of the above embodiments may be applied to a general heat treatment apparatus for performing heat treatment on a wafer used in semiconductor manufacturing in an appropriate gas atmosphere.
Examples of the heat treatment apparatus include a thermal diffusion apparatus, a thermal oxidation apparatus, a reflow apparatus, an annealing apparatus, a CVD apparatus, and an ashing apparatus.

1 is a schematic longitudinal sectional view of a horizontal heat treatment apparatus 10 according to a first embodiment of the present invention. The characteristic view which shows the temperature distribution in the process tube 11 in 1st Embodiment. The schematic longitudinal cross-sectional view of the horizontal type heat processing apparatus 30 in 2nd Embodiment which actualized this invention. The characteristic view which shows the temperature distribution in the process tube 11 in 2nd Embodiment. The schematic longitudinal cross-sectional view of the horizontal heat processing apparatus 40 in 3rd Embodiment which actualized this invention. The schematic longitudinal cross-sectional view of the horizontal heat processing apparatus 40. FIG. The schematic longitudinal cross-sectional view of the horizontal heat processing apparatus 40. FIG. The characteristic view which shows the temperature distribution in the process tube 11 in 3rd Embodiment.

Explanation of symbols

10, 30, 40 ... Horizontal heat treatment device 11 ... Process tube 11a ... Furnace depth (closed end)
11b ... Furnace (open end)
12 ... Gas introduction pipe 12
13 ... Exhaust port 14 ... Closing lid 15a-15c ... Heater 16a-16c ... Spike thermocouple 17 (17a-17e), 31 (31a-31c), 41 (41a-41c), 42 (42a) ... Profile thermocouple 17f , 31d, 41d, 42b ... protection tube 18, 19 ... measuring device 20 ... temperature control device Ea ... first region Eb ... soaking region Ec ... second region La ... first predetermined distance Lb ... second predetermined distance α, γ ... Boundary part

Claims (4)

A heat treatment apparatus that accommodates a wafer used in semiconductor manufacturing in a process tube, supplies an appropriate gas into the process tube, heats the wafer in the gas atmosphere, and performs heat treatment,
The process tube has a closed closed end and an open open end;
A gas introduction pipe for introducing gas into the process tube is connected to the closed end,
The open end is opened with a discharge port for exhausting the gas in the process tube, and a closing lid for closing the open end is attached,
In the process tube, there are a soaking area controlled at a constant temperature, a first area from the soaking area to the closed end, and a second area from the soaking area to the open end. Set,
A heater for heating the outer peripheral wall surface of the process tube;
First temperature detecting means for detecting the temperature of the outer peripheral wall surface of the process tube;
Second temperature detecting means for detecting the temperature in the process tube;
Temperature control means for performing temperature control of the heater based on the temperature detection result by the first temperature detection means, and correcting the temperature control based on the temperature detection result by the second temperature detection means,
The second temperature detecting means includes
A first detector that is arranged in the first region and detects the temperature of the arrangement location;
A second detection unit that is arranged at a boundary portion between the first region and the soaking region and detects the temperature of the arrangement part;
A third detection unit that is arranged in the soaking area and detects the temperature of the arrangement part;
A fourth detector that is arranged at a boundary portion between the soaking area and the second area and detects the temperature of the arrangement place;
A heat treatment apparatus comprising: a fifth detection unit arranged in the second region and detecting a temperature of the arrangement part. A heat treatment apparatus that accommodates a wafer used in semiconductor manufacturing in a process tube, supplies an appropriate gas into the process tube, heats the wafer in the gas atmosphere, and performs heat treatment,
The process tube has a closed closed end and an open open end;
A gas introduction pipe for introducing gas into the process tube is connected to the closed end,
The open end is opened with a discharge port for exhausting the gas in the process tube, and a closing lid for closing the open end is attached,
In the process tube, there are a soaking area controlled at a constant temperature, a first area from the soaking area to the closed end, and a second area from the soaking area to the open end. Set,
A heater for heating the outer peripheral wall surface of the process tube;
First temperature detecting means for detecting the temperature of the outer peripheral wall surface of the process tube;
Second temperature detecting means for detecting the temperature in the process tube;
Temperature control means for performing temperature control of the heater based on the temperature detection result by the first temperature detection means, and correcting the temperature control based on the temperature detection result by the second temperature detection means,
The second temperature detecting means includes
A first detection unit that is arranged inside the soaking area by a first predetermined distance from a boundary portion between the first area and the soaking area, and detects the temperature of the arrangement location;
A second detection unit that is arranged in the soaking area and detects the temperature of the arrangement part;
A heat treatment apparatus comprising: a third detection unit that is disposed inside the soaking area by a second predetermined distance from a boundary portion between the soaking area and the second area, and that detects a temperature of the arrangement location. . A heat treatment apparatus that accommodates a wafer used in semiconductor manufacturing in a process tube, supplies an appropriate gas into the process tube, heats the wafer in the gas atmosphere, and performs heat treatment,
The process tube has a closed closed end and an open open end;
A gas introduction pipe for introducing gas into the process tube is connected to the closed end,
The open end is opened with a discharge port for exhausting the gas in the process tube, and a closing lid for closing the open end is attached,
In the process tube, there are a soaking area controlled at a constant temperature, a first area from the soaking area to the closed end, and a second area from the soaking area to the open end. Set,
A heater for heating the outer peripheral wall surface of the process tube;
First temperature detecting means for detecting the temperature of the outer peripheral wall surface of the process tube;
Second temperature detecting means and third temperature detecting means for detecting the temperature in the process tube;
The temperature of the heater is controlled based on the temperature detection result by the first temperature detection means, and after the temperature control is corrected based on the temperature detection result by the second temperature detection means, the temperature by the third temperature detection means Temperature control means for correcting the correction result again based on the detection result,
The second temperature detecting means includes
A first detection unit that is arranged at a boundary portion between the first region and the soaking region and detects the temperature of the arrangement part;
A second detection unit that is arranged in the soaking area and detects the temperature of the arrangement part;
A third detection unit that is arranged at a boundary portion between the soaking area and the second area and detects the temperature of the arrangement part;
The third temperature detecting means includes
A heat treatment apparatus, wherein the temperature is detected over the entire length of the process tube while being moved from the open end to the closed end. In the heat processing apparatus of any one of Claims 1-3,
The heater is
A first heater for heating an outer peripheral wall surface of the process tube corresponding to an outer portion of the first region;
A second heater for heating an outer peripheral wall surface of the process tube corresponding to an outer portion of the soaking area;
A third heater for heating the outer peripheral wall surface of the process tube corresponding to the outer portion of the second region,
The first temperature detecting means includes
A first detector for detecting a temperature of an outer peripheral wall surface of the process tube corresponding to a boundary portion between the first region and the soaking region;
A second detector for detecting the temperature of the outer peripheral wall surface of the process tube corresponding to the soaking area;
A third detection unit that detects a temperature of an outer peripheral wall surface of the process tube corresponding to a boundary portion between the soaking area and the second area;
The temperature control means performs individual temperature control for each of the first to third heaters.

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