JP2006245492A - Equipment and method for heat treating substrate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide equipment and a method for heat treating a substrate in which a surface temperature in a treatment chamber can be prevented suitably from lowering. <P>SOLUTION: The equipment for heat treating a substrate arranged in a treatment chamber comprises the treatment chamber containing the substrate in a gas atmosphere surrounded by an inner wall face member, a low heat resistance member 10 arranged at a position subjected to thermal effect of the inner wall face member in the vicinity of the exterior of the process chamber, a mechanism for cooling the low heat resistance member, and a mechanism for interrupting cooling action to the inner wall face member provided between the low heat resistance member 10 and the inner wall face member. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a substrate heat treatment apparatus and a substrate heat treatment manufacturing method for heat treating a substrate installed in a process chamber.

  Conventionally, in a manufacturing process in which a semiconductor device such as an LSI or a semiconductor substrate such as a transistor is formed on a glass substrate, a heat treatment process is performed in which activation, oxidation, hydrogenation, and the like are performed by heat-treating the substrate. In such a substrate heat treatment process, a batch type substrate heat treatment apparatus for simultaneously heat treating a plurality of substrates in a quartz glass reaction tube, or a substrate heat treatment apparatus for heating substrates one by one by light irradiation using a lamp, diffusion 2. Description of the Related Art There is known a substrate heat treatment apparatus that heats a substrate by blowing a heating gas through the apparatus.

Patent Document 1 listed below discloses a substrate heat treatment apparatus that heats a substrate by spraying a heating gas such as water vapor through a diffusion device. According to this substrate heat treatment apparatus, it is disclosed that the substrate can be heated at high speed and uniformly because the substrate can be heated by blowing the heating gas through the diffusion device. The inside of the process chamber is made into a gas atmosphere containing, for example, water vapor by a heating gas, a temperature lowering gas, a cooling gas, or the like. The gas atmosphere is formed in the process chamber by being formed in a space surrounded by an inner wall surface member that forms the inner wall of the process chamber.
Japanese Patent No. 3501768

  In the substrate heat treatment apparatus as in Patent Document 1 below, a low heat resistant member such as rubber may be disposed in the vicinity of the outside of the inner wall surface member that forms the process chamber, and at a location that is affected by the heat of the inner wall surface member. is there. For example, in the process chamber described in Patent Document 1, an upper inner wall surface member serving as a lid portion and a lower inner wall surface member covered by the lid portion are combined to form a process chamber. This joint is sealed with a sealing material composed of a low heat-resistant material such as polytetrafluoroethylene-based material or fluororubber-based material, and this sealing material causes the gas atmosphere inside the process chamber to flow out from the joint to the outside of the process chamber. To prevent it.

  The sealing material, which is a low heat-resistant member provided in the joint portion, comes into contact with the inner wall surface member of the process chamber that becomes high in heat, and the sealing material may be melted by high heat from the process chamber. is there. On the other hand, the sealing material, which is a low heat-resistant member, is protected from high heat, and the sealing material is melted by high heat from the process chamber. It is conceivable to use a substrate heat treatment apparatus provided with a cooling mechanism for preventing problems such as

  However, in the substrate heat treatment apparatus provided with such a cooling mechanism, the cooling action cools the inner wall surface member in the vicinity and the inner wall surface member, and lowers the temperature of the inner wall surface in contact with the gas atmosphere inside. There is a case. When the temperature of the inner wall surface decreases, the internal gas condenses and may cause condensation due to this gas. When dew condensation occurs, there may be a problem that corrosion of the inner wall surface at the position where dew condensation is generated accelerates more than the gas atmosphere due to this dew condensation.

  The present invention has been made to solve at least one of the above-described problems, and an object of the present invention is to provide a substrate heat treatment apparatus and a substrate heat treatment manufacturing method that can more suitably prevent the temperature inside the process chamber from being lowered.

  A substrate heat treatment apparatus for heat-treating a substrate installed in a process chamber according to the present invention includes a process chamber in which a substrate is housed in an interior surrounded by an inner wall surface member, and the inside is made a gas atmosphere, and the process A low heat resistant member provided in a position near the outside of the chamber and affected by the heat of the inner wall surface member; a cooling mechanism for cooling the low heat resistant member; the low heat resistant member; and the inner wall surface member; And a cooling action blocking mechanism for blocking the cooling action on the inner wall surface member.

  A substrate heat treatment manufacturing method for heat-treating a substrate installed in a process chamber according to the present invention is a process chamber in which a substrate is housed in an interior surrounded by an inner wall surface member, and the interior is made a gas atmosphere. And a substrate heat treatment apparatus including a low heat-resistant member provided in a position near the outside of the process chamber and affected by the heat of the inner wall surface member, and a cooling mechanism for cooling the low heat-resistant member, The substrate is manufactured by heat-treating the substrate while blocking the cooling action on the inner wall surface member by the cooling mechanism.

  It is preferable that the cooling action blocking mechanism includes at least one of a heat insulating member and a heater for heating the inner wall surface member.

  The inner wall surface member from which the cooling action is blocked is preferably a member constituting an accommodation valve that is opened when the substrate is accommodated.

  The low heat resistant member is preferably a member including at least one of a polytetrafluoroethylene material and a fluororubber material.

  Preferably, the process chamber is formed by joining a plurality of inner wall surface members at a joining portion, the joining portion is sealed with a sealing material, and the sealing material is a low heat resistant member.

  It is preferable to remove the gas forming the gas atmosphere from the process chamber to the outside that can be exhausted.

  The gas atmosphere is preferably a gas atmosphere containing water vapor.

  It is preferable to provide a gas pipe having a gas injection port through which the gas forming the gas atmosphere supplied from the gas introduction part blows out to the substrate surface.

The gas forming the gas atmosphere is a heating gas for heating the substrate surface,
Preferably, the gas pipe is a heating pipe, and the heating gas includes a gas diffusion device that diffuses and blows the heating gas from the gas injection port through the heating pipe.

  It is preferable that a heating furnace for heating the heating gas is included.

  The heating pipe is preferably bent along the inner wall surface member of the process chamber.

  It is preferable to provide a substrate lifting / lowering device that moves the substrate between an upper position where the heating gas is blown to the substrate via the diffusion device and a lower position in the process chamber lower than the upper position. It is.

  A perforated plate that is formed in a shape along the substrate and divides the process chamber in the vertical direction, and the diffusion device supplies the heating gas heated when passing through the heating pipe to the perforated plate. It is preferable that the gas is discharged into an upper space of the process chamber partitioned by, and further passed through the hole of the perforated plate, and then diffused and sprayed onto the substrate surface in the process chamber.

  It is possible to provide a substrate heat treatment apparatus and a substrate heat treatment manufacturing method that can more suitably prevent the temperature inside the process chamber from being lowered.

EMBODIMENT OF THE INVENTION Below, the form for inventing is demonstrated based on drawing. In addition, about this embodiment, it is only one form for implementing this invention, and this invention is not limited by this embodiment. Hereinafter, it demonstrates using drawing.
“Configuration of substrate heat treatment equipment”
FIG. 1 is a longitudinal sectional view of a substrate heat treatment apparatus 100 according to this embodiment. As shown in FIG. 1, the substrate heat treatment apparatus 100 of this embodiment includes a quartz process tube 2 that houses a substrate 1, a heating furnace 3 that is attached to the upper portion of the process tube 2, and an upper wall member of the process tube 2. The quartz heating pipe 4 disposed in the chamber, two ring-shaped preheating furnaces 5 provided inside the process tube 2, a flange 6 for supporting the process tube 2 from below, and the substrate 1 as a process tube 2 is provided with a substrate elevator 7 for moving in the vertical direction inside the unit 2.

A sealing material 10 (FIG. 3), which is a low heat resistance member, is interposed between the process tube 2 and the flange 6, whereby the airtightness between the process tube 2 and the flange 6 is maintained.
As shown in FIG. 1, the inside of the process tube 2 is partitioned in the vertical direction in FIG. 1 by a perforated plate 21 in which a large number of holes (paths) are formed. Further, on the side wall of the process tube 2, a door 22 for taking in and out the substrate, gas exhaust ports 23 and 24 for exhausting gas in the process tube 2, and cooling the substrate 1 in the process tube 2. A cooling gas inlet 25 for introducing the cooling gas is provided. FIG. 1 illustrates a state in which the process tube 2 is opened and a state in which the door 22 is closed so as to maintain airtightness as the door 22 moves left and right.

  The ring-shaped preheating furnace 5 is surrounded by a quartz cover 5a, thereby preventing contamination in the process tube 2.

  The heating furnace 3 is attached to the process tube 2 so as to maintain airtightness in the process tube 2. As shown in FIG. 1, the heating furnace 3 includes a furnace body 3 a that covers the opening of the process tube 2, and a heater 3 b that is attached to the inner surface side of the furnace body 3 a. The heater 3b is made of a resistor, and the heater 3b is heated by applying a voltage to the resistor. In order to prevent contamination inside the process tube 2 due to the heater 3b and to uniformly heat the substrate 1, the inner surface of the heating furnace 3 is made of translucent or ground glass quartz that covers the heater 3b. The cover 31 is attached.

  As shown in FIG. 1, the substrate elevator 7 is attached to the flange 6 while maintaining the airtightness of the process tube 2. The substrate elevator 7 is attached to the arm 71 that penetrates the opening formed in the center of the two preheating furnaces 5 and the cover 5a, the actuator 72 that drives the arm 71 in the vertical direction in FIG. And a substrate holder 73 made of quartz or carbon that supports the substrate 1. The substrate holder 73 has a structure in which a quartz pin 73b is welded to an appropriately sized quartz plate 73a supported horizontally. The substrate 1 is held in contact with the pins 73b. The size of the substrate holder 73 is determined according to the size of the substrate 1 and the size of the horizontal cross section inside the process tube 2, and also has the role of adjusting the exhaust conductance.

  As shown in FIG. 1, a space 26 having a predetermined gap is formed above the perforated plate 21 between the perforated plate 21 and the inner wall surface of the process tube 2. The gap (the vertical width in FIG. 1) of the space 26 is set to about 12 mm, for example. The size of the gap is desirably about 10 to 15 mm.

  As shown in FIG. 2, a heating pipe 4 that is bent in a complicated manner is attached to the upper wall member of the process tube 2. A heating gas discharge port 4a is provided at one end of the heating pipe 4, and a heating gas introduction port 4b is provided at the other end. As shown in FIG. 1, the heating gas inlet 4 b penetrates the heating furnace 3. The gas discharge port 4 a passes through the partition wall of the process tube 2 and opens into a space 26 between the perforated plate 21 and the inner wall surface of the process tube 2. Further, a temperature lowering gas inlet 9 for introducing a gas for cooling the substrate 1 passes through the partition walls of the heating furnace 3 and the process tube 2 and opens into the space 26.

  As shown in FIG. 2, since the gas discharge port 4a is opened near the center of the process tube 2, the gas pressure near the center of the gap 26 increases, and the amount of gas ejection near the center tends to increase. For this reason, the diameter of the hole of the perforated plate 21 is small near the center of the process tube 2 and is large at the peripheral portion, whereby the amount of heating gas blown out can be made uniform over the entire substrate 1. Further, the hole frequency (number per area) may be increased in the peripheral portion of the gas chamber 2 while the hole diameter is formed constant. The hole diameter is preferably about 0.5 to 1 mm.

  Next, a procedure for substrate heat treatment using the substrate heat treatment apparatus 100 for a gas chamber according to the present embodiment will be described. First, the door 22 of the process tube 2 is opened, and the substrate 1 is set on the substrate holder 73. At this time, the gas is introduced from the temperature lowering gas inlet 9 (gas flow rate: 80 to 100 l / min), the substrate 1 is set, and then the door 22 is closed. At this time, the board | substrate 1 exists in the low temperature part in the process tube 2 which is the lowest point of the drive range of the elevator 7. FIG. FIG. 1 shows the position of the substrate 1 at this time.

  Next, preheating is performed with the gas flowing from the temperature lowering gas inlet 9. Preheating is performed by the heater 3 b of the heating furnace 3 and the heater of the preheating furnace 5. By the end of preheating, the temperature of the heater 3b rises to a set temperature (for example, 800 ° C.).

  After the preheating, the arm 71 of the elevator 7 is driven to move the substrate 1 placed on the substrate holder 73 to the uppermost heating position. FIG. 1 shows the position of the substrate 1 at this time. While the substrate 1 is raised, the temperature of the substrate 1 is raised by decreasing the flow rate of the temperature-falling gas and increasing the flow rate of the heating gas supplied through the heating pipe 4. This operation is performed while the substrate 1 moves from the lowest point to the highest point.

  After the substrate 1 reaches the uppermost point, the introduction of the temperature lowering gas is stopped, and only the heating gas is introduced through the heating pipe 4 (gas flow rate: 20 l / min to 50 l / min). Further, by resetting the temperature of the heating furnace 3 and controlling the heater 3b of the heating furnace 3, the substrate 1 is heated to a predetermined temperature (for example, 720 ° C.) for a predetermined time. While the heating gas passes through the heating pipe 4, the heating gas is heated by the heating furnace 3. The heated gas supplied to the space 26 is dispersed when passing through the holes of the perforated plate 21, hits the entire substrate 1, and flows along the surface of the substrate 1 to uniformly heat the substrate 1. Thereafter, the gas passes between the substrate 1 and the process tube 2 and is exhausted through the exhaust ports 23 and 24.

  In this way, by supplying the heating gas through the perforated plate 21 with the substrate 1 being close to the perforated plate 21, the gas can be stirred on the surface of the substrate 1, and the temperature of the substrate surface can be increased. Can be made uniform and the temperature can be kept constant for a predetermined time.

  At this time, the substrate 1 is also directly heated by the heat of the heating furnace 3. The gas chamber 2 is made of opaque or frosted glass-like quartz in order to minimize the influence of light irradiated from the heating furnace 3 and to disperse the light.

  As described above, the substrate 1 is heated uniformly at high speed by the heat of the heating furnace 3, the energy transfer of the heating gas, and the heat conduction.

  Next, the arm 71 of the elevator 7 is driven to uniformly lower the temperature of the entire substrate 1 while gradually lowering the substrate 1 placed on the substrate holder 73 from the highest point to the lowest point. At this time, the setting and power of the heater 3b of the heating furnace 3 are adjusted, the flow rate of the heating gas is decreased, and the flow rate of the cooling gas introduced from the cooling gas introduction port 9 is increased. This operation is performed until the substrate 1 reaches the lowest point. At this time, by appropriately setting the temperature of the temperature lowering gas (for example, 400 to 500 ° C.), the temperature of the substrate 1 can be decreased at a high speed without increasing the temperature difference in the substrate 1. In order to lower the temperature without damaging the substrate 1, it is necessary to appropriately adjust the flow rate of the temperature-lowering gas and the lowering speed of the substrate 1 by the elevator 7. In particular, when the substrate 1 is a glass substrate, warping, distortion, or cracking may occur if there is a large temperature difference in the substrate 1 at a high temperature. Therefore, reducing the temperature at a high speed while suppressing the temperature difference in the substrate 1 is an indispensable element in the high-temperature heat treatment process. According to the apparatus of this embodiment, when the temperature is lowered, it is possible to spray the temperature-falling gas evenly on the substrate surface, stir the gas, and gradually move the substrate 1 away from the heat source. Is possible.

  When the substrate 1 reaches the lowest point, the supply of the temperature lowering gas and the heating gas is stopped, and the cooling gas is introduced from the cooling gas inlet 25 to cool the substrate 1. As a result, the substrate 1 can be cooled to a temperature that can be transported by the robot while being placed on the substrate holder 73. At this time, the power of the heater 3b of the heating furnace 3 may be zero. After the temperature of the substrate 1 drops to the set temperature, the door 22 is opened and the substrate 1 is taken out.

  By repeating the above cycle, the substrate 1 can be sequentially heated.

  In the present embodiment, the substrate 1 is first set at the lowest point, and the substrate 1 can be heated to a constant temperature at this position, so that damage to the substrate due to rapid temperature rise can be prevented.

  Examples of the substrate include, but are not limited to, a semiconductor substrate such as a flat panel device as exemplified in the present embodiment.

  The processing gas for processing the semiconductor substrate includes, but is not limited to, water vapor. The processing gas is not limited to water vapor gas, and may be nitrogen, oxygen, argon or the like. Here, in the case of water vapor, the gas processing and manufacturing apparatus according to the present embodiment is suitable from the viewpoint of the case of aiming at oxidation of a semiconductor film or the case of using water vapor having a large heat capacity as a means for transferring thermal energy.

"Cooling device and cooling action cutoff mechanism"
The cooling device and the cooling action blocking mechanism according to this embodiment will be described with reference to FIG. The substrate heat treatment apparatus 100 includes a sealing material 10 between the flange 6 and the inner wall surface member of the process tube 2.

  The sealing material 10 is provided between the flange 6 and the process tube 2 at a position where both of the flange 6 and the inner surface of the process tube 2 are recessed laterally. The flange 6 and the process tube 2 are bent in the lateral direction in the vicinity of the joint portion so as to form a position recessed in the lateral direction, and the sealing material 10 seals between the flange 6 and the process tube 2 on the inner surface of the bent portion. It has a structure.

  The sealing material 10 is a low heat resistant member. For example, polytetrafluoroethylene materials, fluororubber materials, and the like can be given.

  A tubular cooling water flow path 12 for flowing cooling water is provided at a position outside the flange 6 and the inner wall surface member of the process tube 2 and in contact with the lower surface of the bent portion of the flange 6 serving as the lower surface of the sealing material 10. Is formed. The cooling water flow path 12 has a width substantially equal to that of the sealing material 10. The cooling water flow path 12 cools the sealing material 10 on the inner surface of the bent portion of the flange 6 through the lower surface of the bent portion of the flange 6 by the flow of the cooling water into the tubular shape, thereby reducing the heat resistance from high heat by heat treatment. This is a cooling mechanism that protects the sealing material 10 that is an adhesive member. As such a cooling mechanism, there is a cooling method of hot water, gas, etc. that is so low that it does not affect the low heat resistance member in addition to using cooling water.

  FIG. 4 shows a range indicated by A in FIG. 3, which is an enlarged view of a joint portion between the flange 6 and the process tube 2 sealed by the sealing material 10. A heater 14 is provided between the flange 6 and the side surface of the coolant flow path 12. The heater 14 prevents the cooling effect of the cooling water channel 12 from being transmitted to the flange 6. Thereby, since the inner surface of the flange 6 is cooled and can be prevented from being lowered in temperature, it is possible to prevent condensation due to cooling of the internal gas atmosphere. Note that a heat insulating member can be used instead of the heater 14. Also in the range indicated by A ′ in FIG. 3, the heater 14 is provided on the side surface of the cooling water flow path 12 and between the flange 6. The heater 14 prevents the cooling effect of the cooling water channel 12 from being transmitted to the flange 6.

  A gas exhaust pipe 16 is provided at the lower end of the flange 6 so that gas in a gas atmosphere can be exhausted. After exhausting the gas, the gas concentration in the gas atmosphere is reduced by cooling the inside, so that condensation of the gas can be prevented. The gas exhaust pipe 16 is connected to a gas-liquid separator 18, and the exhausted gas is liquefied by the gas-liquid separator 18 and discharged.

  The present embodiment is not limited to the seal material 10 and is applied to a low heat resistant member provided in a position near the outside of the process chamber and affected by the heat of the inner wall surface member, and a cooling member for cooling the member. be able to. The inner wall surface member is not limited to the side surface, and may be an inner wall surface member of the door 22 that is an upper surface, a lower surface, or the like, and further is a storage valve that is opened when the substrate is stored.

It is sectional drawing of the gas chamber of this embodiment. It is a figure which shows the piping for heating of this embodiment. It is explanatory drawing of the substrate heat processing apparatus of this embodiment. It is explanatory drawing of the substrate heat processing apparatus of this embodiment.

Explanation of symbols

1 Substrate 2 Gas Chamber 3 Heating Furnace 4 Heating Pipe 7 Substrate Elevator (Substrate Elevator)
9 Gas inlet for cooling (cooling gas supply device)
DESCRIPTION OF SYMBOLS 10 Sealing material 12 Cooling water flow path 14 Heating heater 16 Gas exhaust pipe 18 Gas-liquid separation device 21 Perforated plate (diffusion device)
26 space

Claims (8)

A substrate heat treatment apparatus for heat treating a substrate installed inside a process chamber,
A process chamber in which a substrate is housed in an interior surrounded by an inner wall surface member, and the inside is made a gas atmosphere;
A low heat-resistant member provided in the vicinity of the outside of the process chamber and at a position affected by the heat of the inner wall surface member;
A cooling mechanism for cooling the low heat resistant member;
A substrate heat treatment apparatus comprising: a cooling action blocking mechanism that is provided between the low heat resistant member and the inner wall surface member and blocks a cooling action on the inner wall surface member. The substrate heat treatment apparatus according to claim 1,
The cooling action blocking mechanism is a substrate heat treatment apparatus including at least one of a heat insulating member and a heater for heating the inner wall surface member. The substrate heat treatment apparatus according to claim 1 or 2,
The inner wall surface member from which the cooling action is blocked is a substrate heat treatment apparatus that is a member constituting an accommodation valve that is opened when the substrate is accommodated. A substrate heat treatment apparatus according to any one of claims 1 to 3,
The substrate heat treatment apparatus, wherein the low heat resistant member is a member including at least one of a polytetrafluoroethylene material and a fluororubber material. A substrate heat treatment apparatus according to any one of claims 1 to 4,
The process chamber is formed by coupling a plurality of inner wall surface members at a coupling portion,
The coupling portion is sealed by a sealing material,
The substrate heat treatment apparatus, wherein the sealing material is a low heat resistant member. A substrate heat treatment apparatus according to any one of claims 1 to 5,
A substrate heat treatment apparatus for removing a gas that forms the gas atmosphere to the outside that can be exhausted from the process chamber. A substrate heat treatment apparatus according to any one of claims 1 to 6,
The substrate heat treatment apparatus, wherein the gas atmosphere is a gas atmosphere containing water vapor. A substrate heat treatment manufacturing method for manufacturing a substrate by heat-treating a substrate installed in a process chamber,
A substrate is housed in an interior surrounded by an inner wall surface member, and the inside of the process chamber is set to a gas atmosphere. A substrate heat treatment apparatus comprising: a low heat resistance member that is formed; and a cooling mechanism that cools the low heat resistance member.
A substrate heat treatment manufacturing method of manufacturing a substrate by heat-treating the inner wall member by blocking the cooling action by the cooling mechanism.

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