JP3383784B2 - Heat treatment equipment for semiconductor wafers - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to chemical vapor deposition (CVD) on a semiconductor wafer such as a silicon wafer,
The present invention relates to a heat treatment apparatus that performs impurity diffusion, annealing, epitaxial growth, and other processing in a semiconductor manufacturing process.

[0002]

2. Description of the Related Art In this type of semiconductor wafer heat treatment apparatus, a large number of semiconductor wafers mounted on and supported by a heat-resistant wafer boat made of quartz or the like are formed by heat-resistant and pressure-resistant containers such as quartz tubes. It is housed in a chamber (diffusion chamber, reaction chamber, etc.), a processing gas is introduced into the processing chamber, and heating means is provided around the outer periphery of the processing chamber to set a desired uniform high temperature state in the processing chamber. And heat treatment is performed.

In this heat treatment apparatus for semiconductor wafers, a resistance heating element formed by a coil (spiral) -shaped heating wire is used as a heating means, and the outer periphery of this heating wire is supported by a spacer made of alumina-based refractory or the like, and a ceramic is also used. A structure is used in which a heat insulating material such as a fiber is wound and the outside is wrapped with a metal plate such as an aluminum plate.

[0004]

However, in the heat treatment apparatus using the resistance heating element as the heating means, there is a time lag in the case of rapidly raising or lowering the temperature of the processing chamber or when performing minute temperature control. It takes a long time to stabilize, and it is extremely difficult to achieve uniform heating at a desired temperature quickly and precisely with a minute setting.In particular, when the temperature is lowered, the heat insulating material hinders the temperature drop. There is a possibility that the required high-quality heat treatment may be impaired, or that treatment time may be required, resulting in a decrease in productivity and an increase in electricity bill.

Further, the inside of the quartz tube forming the processing chamber is placed under a low pressure condition so that there is a pressure difference between the inside and the outside, and some of the processing gas introduced inside is harmful if leaked.
For example, in the event of a large earthquake, the quartz pipe may be damaged by the impact and the pressure difference between the inside and outside, and special safety measures are required to prevent the processing gas from leaking to the outside in case of damage. It was necessary separately.

Further, recently, a semiconductor wafer having an extremely large diameter has been used, and it has become more difficult to rapidly uniformize the temperature of a processing chamber, which has a large volume. Although the peripheral portion of the quartz tube provided with the heating wire is sufficiently heated, the heat may not reach the central portion sufficiently and a temperature difference may occur.

Further, since particles are easily generated from the heating wire, the particles may impede the clean environment required in the semiconductor manufacturing process.

Therefore, the present invention provides a heat treatment apparatus which can solve the above problems in the conventional heat treatment apparatus using a resistance heating element as a heating means, and its main purpose is to rapidly raise or lower the temperature, An object of the present invention is to provide a heat treatment apparatus for semiconductor wafers, which is easy to control when performing minute temperature control and improves responsiveness, and which does not impair the environment and is highly safe.

[0009]

According to the present invention, there is provided a processing chamber into which a processing gas is introduced, a heating means for heating a semiconductor wafer housed in the processing chamber, and a heating chamber surrounding the processing chamber. A semiconductor wafer heat treatment apparatus in which a heating chamber is formed by mounting the means is targeted for implementation.

The heating means of the heat treatment apparatus for semiconductor wafers according to the present invention is composed of a large number of heaters for heating light radiation having an annular light radiation portion formed on the tip side of the power feeding portion. It is arranged in parallel at predetermined intervals along the chamber. (Claim 1)

In the heat treatment apparatus according to the first aspect of the present invention, light heating is performed by light radiation energy of a heater for light radiation heating as heating means, and this light heating is performed by collectively or individually combining a plurality of heaters for light radiation heating. Since the temperature can be controlled by controlling in a state, it is easier to perform a rapid temperature increase or decrease and a minute temperature control, as compared with a conventional heat treatment apparatus using a coil-shaped resistance heating element as a heating means. In addition, the responsiveness of control can be improved, and the uniform heat treatment can be performed while improving the work efficiency and saving the electricity bill.

Further, since the heating means itself does not generate heat unlike the resistance heating element, it is not necessary to wrap a thick heat insulating material such as ceramic fiber around the outside of the heating means to protect it, and the apparatus is small and highly safe. It is a clean heating means that does not require the work of removing the binder in the heat insulating material by performing the idle operation in the initial stage, and has less generation of particles.

A heater for heating light radiation according to claim 1 is
Although it is possible to use an arc lamp or the like, it is desirable to use an infrared radiation halogen lamp because the density of radiant energy is large and the entire apparatus can be downsized, and the color temperature is high. (Claim 2)

The heating chamber in the heat treatment apparatus according to claim 1 or 2 is formed in an outer cover in which annular grooves that are opened inward and in which the light emitting portions are individually accommodated are provided in parallel.
A configuration in which a reflecting surface is provided in the annular groove can be adopted. (Claim 3)

According to another aspect of the heat treatment apparatus of the present invention, the light emitting portion of each light radiation heating heater housed in each annular groove comprises:
Light radiant energy can be efficiently radiated to the processing chamber side with the help of the reflecting surface. This reflecting surface may be formed by attaching a mirror surface plate, but it is formed by mirror-finishing the annular groove itself. You can also do it.

The heating chamber in the heat treatment apparatus according to any one of claims 1 to 3 may have a structure in which the heating chamber is formed in a hermetically sealed state and a pressure adjusting gas is supplied to and exhausted from the inside. (Claim 4)

In the heat treatment apparatus according to the fourth aspect of the present invention, the inside of the heating chamber forms a heat retaining layer by a pressure adjusting gas such as nitrogen gas to maintain a desired set temperature, and the inside of the heating chamber is lowered when the set temperature is lowered. The temperature can be rapidly lowered by setting it to the atmosphere, and if the pressure adjustment gas reduces the pressure difference between the inside and outside of the processing chamber, the inner tube part is prevented from being damaged by the quartz tube forming the processing chamber, It is possible to prevent the processing gas in the processing chamber from leaking to the outside.

The heater for light radiation heating in the heat treatment apparatus according to any one of claims 1 to 4 is configured such that an O-ring is wound around the outer periphery of the power supply portion on the base side so as to protrude outside while the inside and outside of the outer cover are sealed. It is possible to adopt a configuration in which a cooling means for cooling the base side of the projected power feeding portion is provided.
(Claim 5)

In the heat treatment apparatus of the fifth aspect, the inside and outside of the heating chamber is shut off by the O-ring wound around the outer periphery of the power feeding portion on the base side, thereby preventing hot air in the heating chamber from flowing out. In addition, by cooling the base side of the power supply part, preventing damage to the tube body due to the difference in thermal expansion coefficient between the quartz glass forming the power supply tube body and the metal conductor forming the connection pin, Leakage can be prevented, and at the same time, effective cooling can be performed by sealing so that the refrigerant does not flow into the heating chamber.

In the heat treatment apparatus according to any one of claims 1 to 5, the heater for heating the light radiation has a configuration in which the positions of the respective power feeding portions are displaced along the circumferential direction in which the light radiation portion extends. be able to. (Claim 6)

In the heat treatment apparatus according to the sixth aspect, it is possible to prevent the feeding portions which do not emit light from overlapping each other and prevent the heating distribution from becoming non-uniform, and also to prevent the wiring to the feeding portions from being locally concentrated. It can be dispersed.

The processing chamber in the heat treatment apparatus according to any one of claims 1 to 6 is formed of a vertically long cylindrical heat-resistant and light-transmissive inner cylindrical portion having an opening at the bottom side, and the inner cylindrical portion is horizontally supported by a wafer boat. A large number of semiconductor wafers are housed so that they can be taken out by a boat loader, and the outer cover is formed by closing the upper and lower sides of an outer cylinder made of heat-resistant metal with a top plate and a bottom plate, and the outer cylinder is used for heating the light radiation. It is possible to adopt a configuration in which heaters are mounted and the semiconductor wafers are arranged in parallel along the vertical direction in which they are arranged. (Claim 7)

According to a seventh aspect of the present invention, the heat treatment apparatus is suitable for a vertical batch type processing chamber for horizontally holding vertically stacked semiconductor wafers, and the semiconductor wafers are parallel to each other as compared with a horizontal type processing chamber. It is easy to hold the semiconductor wafer, and the heat treatment is uniformly performed on a large number of semiconductor wafers.

In the heat treatment apparatus according to any one of claims 1 to 7, the outer cylinder portion is formed by combining split cylinders having a semicircular cross section from the left and right, and the light radiation heating heaters are alternately arranged in each split cylinder. It is possible to adopt a configuration that is attached to. (Claim 8)

In the heat treatment apparatus of claim 8, the assembling at the time of manufacture and the subsequent maintenance can be facilitated,
Especially effective for maintenance and inspection of heaters for light radiation heating and removal of particles on the inner cylinder part and reflection surface, and the state where the power supply parts of each heater for light radiation heating that do not emit light are evenly distributed to the left and right. To prevent uneven light emission.

In any one of the processing chamber and the heating chamber in the heat treatment apparatus according to the first to eighth aspects, a soaking tube can be provided so as to face the heater for light radiation heating. (Claim 9)

In the heat treatment apparatus of claim 9, a soaking tube is provided when more uniform soaking accuracy is required, and the light radiant energy generated by the light radiant heating heater is converted into radiant heat and uniformly transmitted to the processing chamber. However, the soaking tube can be arranged at a selected position as required.

In the heat treatment apparatus according to any one of claims 1 to 9, auxiliary heating means for heating the semiconductor wafer from above and below in cooperation with the heating means is provided in the heating chamber, and the auxiliary heating means is provided at the tip of the power feeding portion. It is possible to adopt a configuration in which a heater for light radiation heating in which an annular light radiation portion is formed is formed, and a plurality of different diameters are concentrically arranged with respect to the center of the semiconductor wafer. (Claim 10)

In the heat treatment apparatus according to the tenth aspect, particularly when the heat treatment chamber and the heating chamber are large in size and have a large heat capacity, an auxiliary is provided to further stabilize the heating of the center including the upper and lower sides as compared with the outer peripheral side provided with the heating means. The auxiliary heating means is provided with heating means, and a plurality of heaters for heating light radiation having different diameters are concentrically arranged in the auxiliary heating means, so that uniform heating can be performed and there is a temperature difference between the inner and outer circumferences. In this case, it is possible to individually control each of the light radiation heating heaters to measure the soaking.

The outer cover in the heat treatment apparatus according to any one of claims 1 to 6 is formed by an upper case and a lower case which are vertically arranged and removably united with each other, and a cavity formed between the upper case and the lower case. The heat-resistant and translucent disk-shaped partition plates are provided in parallel vertically, and the processing chamber is formed between the upper and lower disk-shaped partition plates, and the upper side of the disk-shaped partition plates and The heating chamber is formed on the lower side, and a holding member for horizontally supporting one to a plurality of semiconductor wafers is provided in the processing chamber. The heater for light radiation heating includes a plurality of disc-shaped partition plates having different diameters. It is possible to adopt a configuration in which the upper case and the lower case are mounted concentrically with respect to the center of the above. (Claim 11)

The heat treatment apparatus of claim 11 is a single-wafer type suitable for heat treatment of a small number of semiconductor wafers, preferably one by one, and in particular, a plurality of heaters for heating light radiation having different diameters as heating means. Since they are arranged concentrically, it is possible to perform uniform heating, and when there is a temperature difference between the inner and outer circumferences, it is possible to individually control each of the light radiation heating heaters and measure the soaking. .

[0032]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A semiconductor wafer heat treatment apparatus according to the present invention will be described below in detail with reference to the accompanying drawings showing a preferred embodiment. FIG. 1 shows a badge type heat treatment apparatus according to the first embodiment. FIG. 2 is a vertical sectional view of FIG.
1 is a plan view showing a main part of the apparatus of FIG. 1, FIGS. 3 and 4 are a plan view and a side view of a heater for light radiation heating used in the apparatus as a heating means, and FIG. 5 is a view showing a second embodiment. A single-wafer type heat treatment apparatus is shown in a longitudinal sectional view, and FIG. 6 is a plan view showing a main part of the apparatus shown in FIG.

The badge type heat treatment apparatus 1 according to the first embodiment includes a processing chamber 2 into which a processing gas is introduced and a processing chamber 2
A heater 4 for heating light radiation used as a heating means for the semiconductor wafer 3 housed in the chamber, and an outer cover for mounting a large number of heaters 4 for heating light radiation surrounding the processing chamber 2 to form a heating chamber 5. ing.

As the light radiation heating heater 4, an infrared radiation halogen lamp in which an annular light radiation portion 8 is formed on the tip side of the power feeding portion 7 is used, and a large number of light radiation portions 8 are arranged along the processing chamber 2. It is mounted on the outer cylinder portion 6 of the outer cover in such a manner as to be arranged in parallel at predetermined intervals to enable lighting and output control collectively or individually or in any combination.

The outer cylindrical portion 6 is provided in parallel with annular grooves 9 which are opened inside the processing chamber 2 and individually accommodate the respective light emitting portions 8. The annular grooves 9 effectively receive the light radiation energy. For use, the inner surface is formed of a mirror-finished reflective surface.

The outer cover is entirely made of a heat-resistant metal material such as aluminum, and the top plate portion 10 and the bottom plate portion 11 are attached to the upper and lower portions of the outer tubular portion 6 to form the heating chamber 5 therein. It is downsized without using a thick heat insulating material unlike the conventional heat treatment apparatus using a resistance heating element as a heating means.

The outer cylinder portion 6 is divided cylinders 6A, 6 having a semicircular cross section.
B is formed by combining from the left and right, and the light emission heating heaters 4 are alternately mounted on each of the divided tubes 6A and 6B, alternately.
This prevents the power supply part 7 which does not emit light from concentrating on one of the left and right sides and impairing the soaking.

The heater 4 for heating the light radiation is arranged such that the base end sides of the two parallel power feeding portions 7, 7 projecting horizontally from the light radiation portion 8 housed in the ring groove 9 are connected to the ring groove 9. Although it is projected to the outside of the outer cylinder portion 6 through a drawing hole formed in the bottom surface, a seal is provided so that the heat in the heating chamber 5 does not flow out through the power feeding portion 7.

That is, the mounting plate 45 having a through hole through which the power feeding parts 7 and 7 are individually inserted is provided in the outer opening of the drawing hole.
Is attached, and O is attached to the outer circumference of each power supply unit 7, 7.
While the ring is attached, the O-ring is locked and held in the through hole of the mounting plate 45, so that the base end sides of the power feeding portions 7, 7 are pulled out to the outside in a state where the inside and outside of the heating chamber 5 are sealed.

The PID temperature control device (not shown) is provided on the base end side of the power supply parts 7 and 7 via a connection pin so that the heaters 4 for heating the light radiation can be controlled collectively or individually or in any combination. ), And the tube portion is cooled by a known cooling means such as water cooling or air cooling provided in the vicinity (not shown), and the quartz glass or the like forming the power feeding tube and the metal conductor forming the connection pin are connected. The damage of the pipe due to the difference of thermal expansion coefficient and the leakage of the enclosed gas in the pipe are prevented.

In the heater 4 for heating the light radiation, if the power feeding parts 7 which do not emit light are concentrated in one place, soaking is impaired, so that the position of each power feeding part 7 is surrounded by the circumference of the light radiation part 8. The wirings are arranged in a staggered manner along the direction, so that the wiring to the PID temperature control device drawn from the connection pin of the power feeding unit 7 is not concentrated in one place, and the wiring is easy and The outer diameter can be reduced.

The heating chamber 5 is formed in a hermetically sealed manner by interposing a seal member at a required place in addition to the above-mentioned power feeding unit 7, and the air supply / exhaust unit 1
A non-flammable pressure adjusting gas such as nitrogen gas is connected to a PID pressure control device (not shown) via 2 to maintain a desired set temperature by using the inside of the pressure adjusting gas as a heat insulating layer. Therefore, the heat retaining effect in the heating chamber 5 increases as the degree of vacuum increases.

Further, when lowering the set temperature, the temperature inside the heating chamber 5 can be rapidly lowered by making it atmospheric, and if the pressure difference between the inside and outside of the processing chamber 2 is reduced by the pressure adjusting gas, the processing chamber 2 can be reduced. It is possible to prevent the inner tube portion 13 from being damaged by the quartz tube or the like forming the inner wall of the inner wall 13 and to prevent the processing gas in the processing chamber 2 from leaking to the outside.

In the processing chamber 2, a heat-resistant and light-transmissive inner cylinder portion 13 having a vertically long cylindrical shape whose bottom is opened is formed of a quartz tube.
A large number of semiconductor wafers 3 horizontally supported by a wafer boat 14 are accommodated in the inner cylinder portion 13.
Is attached to the tip of a rotary shaft 15 of a boat loader (not shown), and can be freely taken in and out by the boat loader.

A processing gas is introduced into the heating chamber 5 from a processing gas introducing portion 16 provided on the upper end side of the inner cylindrical portion 13, and a processing gas exhausting portion 17 provided on the lower end side of the inner cylindrical portion 13 is introduced. Evacuation is performed, and auxiliary heating means for heating the semiconductor wafer 3 from above and below are provided above and below the processing chamber 5 in cooperation with the heating means.

As for the auxiliary heating means, the upper side auxiliary heating means is attached to the top plate portion 10 and the lower side auxiliary heating means is attached to the bottom plate portion 11, respectively. The heater 20 for heating light radiation is formed with a large number of heaters 19 for forming light, and the heater 20 for light radiation heating is formed such that the light emitter 19 projects in a right angle shape from the tip of the feeding portion 18.

The heater 20 for heating the light radiation heating is provided with a plurality of annular grooves (in the illustrated embodiment, the upper annular groove 2) provided in the top plate portion 10 and the bottom plate portion 11 in such a manner as to open inside the processing chamber 2.
(1 is 5 and the lower annular groove 22 is 3)
Are individually housed, the annular grooves 21 and 22 have a plurality of light emitting portions 19 having different diameters with respect to the center of the semiconductor wafer 3.
Are arranged in parallel in a concentric state, and each annular groove 21, 22
Is formed by a reflection surface whose inner surface is mirror-finished.

The light radiant heating heater 20 is formed on the base end side of the power feeding portions 18 and 18 as in the case of the light radiant heating heater 4.
With the ring wound and sealed, the mounting plates 23, 2
4, and the base end side is cooled by cooling means.

Further, between the adjacent annular grooves 21 and 21 and the annular grooves 22 and 22, there are communication holes 25 and 2 formed on the side surfaces.
6, and the heat-resistant and light-transmissive partition plates 27, 2 such as quartz glass attached to the top plate part 10 and the bottom plate part 11 are provided on the front side where the annular grooves 21 and 22 are opened.
Seal at 8.

As a result, sealed auxiliary heating chambers are formed above and below the processing chamber 2 in which the heater 20 for heating the light radiation is mounted, and the auxiliary heating chamber is provided with the air supply / exhaust section as in the case of the heating chamber 5. To a PID pressure control device (not shown) to supply / exhaust the pressure adjusting gas, and the heater 20 for heating the light radiation is turned on by the PID temperature control device (not shown) collectively or individually or in any combination. And output control is performed.

Further, soaking tubes 29 and 30 made of carbon or silicon carbide (SIC) can be selectively provided at a desired position facing the heater 4 for heating the radiant light, and that position can be provided at the inner cylindrical portion 13. The inner heat equalizing pipe 29 along the inner peripheral surface of the inside is provided in the processing chamber 2, or the outer heat equalizing pipe 30 along the outer peripheral surface of the inner cylindrical portion 13 is provided inside the heating chamber 5.

These heat equalizing tubes 29, 30 receive the light radiant energy generated by the heater 4 for heating the light radiant and convert it into radiant heat soaked to heat the semiconductor wafer 3 in the processing chamber 2. When the inner cylinder portion 13 is contaminated by the processing gas and the transmittance may change, the outer heat equalizing pipe 30 is used, and when there is no risk of contamination, the inner heat equalizing pipe 29 having high temperature raising efficiency is used. You can use them properly.

Next, a description will be given of the single-wafer-type heat treatment apparatus 31 according to the second embodiment. An outer cover 34 is formed by an upper case 32 and a lower case 33 arranged vertically.
A disk-shaped partition plate 3 made of a heat-resistant and translucent material such as quartz glass is provided between the cases 32 and 33.
5 and 36 are provided in parallel vertically.

Between the outer covers 34, between the partition plates 35 and 36 mounted via a sealing member such as an O-ring,
Processing chamber 37 which is divided into a hermetically sealed space to form a disk-shaped space
Is formed, and a hermetic heating chamber 39 in which a plurality of heaters 38 for heating light radiation are mounted is formed outside the processing chamber 37.

The heating chamber 39 is provided with a plurality of annular grooves (five in the illustrated embodiment) 40 and 41 provided in the upper case 32 and the lower case 33 so as to open toward the processing chamber 37 for heating the light radiation. The heater 38 is housed, but each annular groove 40, 41
Is formed by a reflection surface whose inner surface is mirror-finished, and has annular grooves 40, 4
In FIG. 1, a plurality of light emitting portions 42 having different diameters from the center of the semiconductor wafer 3 are arranged in parallel in a concentric state.

Like the light radiation heating heater 20, the light radiation heating heater 38 has a structure in which an annular light emitting portion 42 is formed in a rectangular shape at the tip of the power feeding portion 43, and is arranged at the base end side of the power feeding portion 43. Mounting plate 4 with O-ring wound and sealed
The base end side is cooled by cooling means by projecting to the outside via 4, 44, and the adjacent annular groove 40 and annular groove 41 are communicated with each other through communication holes 46, 47 formed in the side surfaces.

As in the case of the heating chamber 5 and the auxiliary heating chamber, a PID pressure control device (not shown) is connected to the heating chamber 39 via the air supply / exhaust unit 48 to supply / exhaust the pressure adjusting gas. Along with the heater 38 for heating the light radiation,
Lighting and output control are performed collectively or individually or in any combination by an ID temperature control device (not shown).

In the processing chamber 37, a support base 49 is provided to support the semiconductor wafer 3, and a processing gas is supplied through a processing gas introduction section 50 and a processing gas exhaust section 51 connected to a PID pressure control device. Although the semiconductor wafer 3 is subjected to heat treatment by the radiant energy of the heater 38 for heating light radiation, which is a heating means, the support base 49 may be a turntable if necessary.

In the outer cover 34, the upper case 32 and the lower case 33 are always joined in a hermetically sealed state via a seal member such as an O-ring, but the work of loading and unloading the semiconductor wafer 3 is performed from the lower case 33 to the upper case. It is performed in a separated state with 32 removed.

In the heat treatment apparatus 31, as in the case of the auxiliary heating means in the heat treatment apparatus 1, the heating chambers 48, 48 separated from the processing chamber 37 by the partition plates 35, 36 are formed. The heat-resistant glass that becomes
Since it is supported in a state of being in contact with the peripheral edges of the openings of the annular grooves 40 and 41 in which the heater 38 for heating the light radiation heating is mounted, a plate thickness of 3 m
Even a thin film having a thickness of m or less can withstand a change in pressure in terms of strength.

Therefore, in this heat treatment apparatus 31, the light radiation heating heater 38 can be structurally arranged close to the processing chamber 37, and the thickness of the partition plates 35 and 36 can be made thin so that the light radiation energy can be reduced. Since it is possible to reduce the loss of the above, it is possible to improve the heating responsiveness to the temperature rise and the temperature decrease from this point as well.

Next, the heat treatment apparatus 1 according to the first embodiment.
The heat treatment method using the above will be described. A large number of semiconductor wafers 3 horizontally supported by the wafer boat 14 are accommodated in the processing chamber 2 by the boat loader, and the inside of the heating chamber 5 is controlled by the PID pressure control device connected to the air supply / exhaust unit 12. Is reduced to a vacuum degree of at least about 10 ^-3 Torr, and the upper and lower auxiliary heating chambers are also reduced to the same vacuum degree, and the heating chamber 5 and the auxiliary heating chambers form a heat insulating layer surrounding the processing chamber 2. To do.

Next, P connected to the processing gas exhaust unit 17
The ID pressure control device pressurizes or depressurizes the inside of the processing chamber 2. This set pressure is approximately 50 to 1 depending on the content of the heat treatment.
The setting can be changed within the range of 0 ^-7 Torr.

Then, the processing gas introducing section 16 is introduced into the processing chamber 2.
The processing gas is introduced from the above. For example, when an oxide film is formed on the semiconductor wafer 3, the processing gas is N ² . While introducing O ₂ , the set pressure in the processing chamber 2 is changed while being adjusted within the range of a pressurized state of ² Kg / cm ² to a depressurized state of 10 ⁻⁷ Torr in conformity with the processing step.

Then, the light radiation heaters 4 and 20 are energized to set the heating chamber 5 and the auxiliary heating chamber to a desired set temperature (for example, 700 to 120 in the case of forming an oxide film).
It is controlled by the PID temperature controller so that it becomes 0 ° C),
In this case, it is possible to individually control each heater for light radiation heating at a required output ratio based on an actual measurement value of a thermocouple thermometer arranged in a key place, or to control to give a desired temperature gradient.

When the temperature is lowered when a new heat treatment is performed after the heat treatment such as film formation is completed, the decompression to the heating chamber 5 and the auxiliary heating chamber in which the heat retaining layer is formed is released and the atmosphere or the pressure is increased. In this state, the temperature inside the heating chamber can be drastically lowered to quickly shift to a new heat treatment operation, and it is also easy to gradually change the set temperature minutely during the heat treatment.

Therefore, it goes without saying that the work efficiency is good and the productivity can be improved and the power consumption can be reduced, but the temperature in the processing chamber 2 can be made to follow a very fine set temperature in a short time. The semiconductor wafer 3
On the other hand, the thermal shock can be reduced, and uniform and high-quality heat treatment can be performed.

The heat treatment apparatus according to the present invention and the conventional heat treatment apparatus using the resistance heating element have an outer diameter of 300 m.
The heat treatment characteristics of 50 m semiconductor wafers were actually measured, and the comparison data are shown below.

In the case of the heat treatment apparatus 1 according to the present invention, temperature rising characteristic 1000 ° C./MIN soaking characteristic ± 0.5 ° C. temperature lowering characteristic 300 ° C./MIN pressure characteristic 2 Kg / cm ² to 10 ⁻⁷ Torr

In the case of the conventional heat treatment apparatus, temperature rising characteristic 15 to 20 ° C./MIN soaking characteristic ± 0.5 ° C. temperature lowering characteristic 5 to 15 ° C./MIN pressure characteristic 760 Torr to 10 ⁻³ Torr

Further, the heat treatment apparatus 3 according to the second embodiment
The heat treatment method using No. 1 is performed in the same manner as in the heat treatment apparatus 1 according to the first embodiment, but the data obtained by actually measuring the heat treatment characteristics when a semiconductor wafer having an outer diameter of 200 mm is subjected to heat treatment are shown below.

Temperature rising characteristics 500 ° C./SEC Soaking characteristics ± 1 ° C. Temperature decreasing characteristics 1000 ° C. to 500 ° C. (1) 2.5 SEC (when the pressure in the heating chamber is increased from 10 ⁻³ Torr to 50 Torr) (2) ) 4SEC (when the pressure in the heating chamber is maintained at 10 ^-3 Torr)

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a badge type heat treatment apparatus according to a first embodiment of the present invention.

FIG. 2 is a plan view of a main part of the apparatus shown in FIG.

3A and 3B are a plan view and a side view of a light radiation heating heater used as a heating unit in the apparatus.

FIG. 4 is a plan view and a side view of another light radiation heating heater used as a heating unit in the apparatus.

FIG. 5 is a vertical cross-sectional view of a single-wafer heat treatment apparatus according to a second embodiment of the present invention.

FIG. 6 is a plan view of a main part of the apparatus shown in FIG.

[Explanation of symbols]

1 Heat treatment equipment (batch type) 2,37 Processing room 3 Semiconductor wafer 4,20,38 Light radiation heater (heating means) 5,39 heating chamber 6 Outer cylinder 6A, 6B split cylinder 7,18,43 Power supply 8,19,42 Light emitting part 9, 21, 22, 40, 41 annular groove 10 Top plate 11 Bottom plate 12,48 Air supply / exhaust section 13 Inner tube 14 wafer boat 15 rotation axis 16,50 Processing gas introduction part 17,51 Process gas exhaust 23, 24, 44, 45 Mounting plate 25, 26, 46, 47 Communication holes 27,28,35,36 Partition board 29,30 Soaking tube 31 Heat treatment equipment (single wafer type) 32 upper case 33 Lower case 34 Outer cover 49 Support

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Claims (2)

(57) [Claims] 1. A heating chamber equipped with heating means for heating a semiconductor wafer in a manner of enclosing a processing chamber in which a semiconductor wafer is accommodated and a processing gas is introduced, and the heating chamber is hermetically sealed by an outer cover. To form a heat-retaining layer, and the heating chamber formed by this heat-retaining layer is depressurized during heat treatment, and pressure is adjusted so that the heating chamber is placed in the atmosphere or under pressure when moving to a new heat treatment operation. It is connected to a pressure adjusting device that supplies and exhausts gas, and the outer covers are placed on top of each other.
It is made up of an upper case and a lower case that are detachably combined.
The cavity formed between the upper and lower cases is
Heat-resistant and translucent disk-shaped partition plates are installed in parallel vertically
To form the processing chamber inside the upper and lower cases.
Provide multiple annular grooves and connect adjacent annular grooves
The heating chamber is formed by communicating with holes, and power is supplied to each annular groove.
An annular light emitting part is formed on the tip side of the part with different diameters
A plurality of heaters for heating light radiation are used as the heating means.
A semiconductor wafer heat treatment apparatus, which is arranged concentrically with respect to the center of a disk-shaped partition plate . 2. The heat treatment apparatus for a semiconductor wafer according to claim 1 , wherein the disk-shaped partition plate is supported while being in contact with the peripheral edge of the opening of the annular groove.