JP2726354B2 - Substrate heat treatment equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tube for performing various heat treatments such as oxidation, annealing, CVD (chemical vapor deposition) or diffusion on various substrates such as semiconductor substrates and ceramic substrates. A furnace core tube having an opening for inserting a substrate boat holding a substrate on one end side in the axial direction and introducing a gas into the inside thereof, and heating means provided around the furnace core tube for heating the substrate; Cooling means for cooling the substrate provided around the opening side of the furnace core tube in the tube axis direction than the heating means, transfer means for holding the substrate boat and transferring the substrate boat in the tube axis direction of the furnace core tube, The present invention relates to a substrate heat treatment apparatus provided with a lid for closing an opening.

[0002]

2. Description of the Related Art As a conventional substrate heat treatment apparatus of this type, one described in Japanese Utility Model Application Laid-Open No. 61-92050 is known. According to this conventional example, as shown in the overall schematic vertical sectional view of FIG. 11, a gas supply port 02 for introducing a process gas is provided above the furnace core tube (process tube) 01 in the vertical direction, and a basket stage is provided below the furnace stage. Substrate (semiconductor wafer) 0 held in basket 04 fixed to 03
Openings (furnace ports) 06 for taking in and out 5... Are formed.

Further, a gas supply port 02 side of a furnace core tube 01 is provided with:
A high-temperature chamber 08 provided with a heater 07 for the high-temperature chamber is provided therearound. On the other hand, a heater 0 for the low-temperature chamber
9 is provided with a low-temperature chamber 010 having cooling means (not shown) for supplying cooling air.

With the above arrangement, when the substrates 05 are taken out of the furnace core tube 01 after the heat treatment, the basket stage 03 is moved down without moving the furnace core tube 01, and the substrates 05 are cooled at a low temperature. It is located in the chamber 010, supplies cooling air in that state, and is configured to drop to a predetermined temperature early.

The reason why the temperature of the substrate 05 is quickly lowered to a predetermined temperature before the substrate 05 is taken out of the furnace tube 01 after the heat treatment is as follows. That is, in this type of substrate heat treatment apparatus, when removing a substrate from the furnace core tube after the heat treatment, for example, in the case of oxidation treatment, there is a problem in that when the substrate is to be removed in a high temperature state, the substrate is thermally strained. Further, when a thin film is formed like a gate oxide film, if the substrate is taken out in a high temperature state, air in the atmosphere is involved, a natural oxide film is generated, and there is a problem that the quality is deteriorated. Also, in the case of metal sintering such as Al sintering, it is necessary to maintain the inside of the furnace core tube in an inert gas atmosphere from a high temperature state to a low temperature state close to normal temperature in order to prevent metal oxidation, and take out the substrate. Can not do. Polysilicon CVD and the like also have the same disadvantages to prevent oxidation.

Therefore, in order to improve the processing performance per unit time, it is necessary to rapidly lower the temperature of the substrate after the heat treatment. Further, in the case of a metal sinter or the like, it is necessary to similarly decrease the temperature from a high temperature state at a high speed in order to prevent wiring defects (metal spikes, silicon nodules).

[0007]

By the way, in the case of the above-mentioned conventional example, the opening (furnace opening) is required during the downward movement for cooling the substrates 05 in the low-temperature chamber 010 or during the cooling in the low-temperature chamber 010. ) 06 is open and its opening (furnace port) 0
Atmospheric components invade into the furnace core tube 01 through 6 to cause a contamination of the process such as a natural oxide film being formed unexpectedly, thereby causing a problem of deterioration in quality.

The present invention has been made in view of such circumstances, and is intended to prevent the intrusion of atmospheric components into a furnace core tube when cooling a substrate without moving the furnace core tube. The purpose is to do.

[0009]

According to the first aspect of the present invention, there is provided a substrate heat treatment apparatus for achieving the above object.
A furnace core tube having an opening for inserting a substrate boat holding a substrate at one end side in the tube axis direction and introducing a gas into the inside thereof, and heating means provided around the furnace core tube to heat the substrate Cooling means provided around the opening side of the furnace core tube in the tube axis direction rather than the heating means to cool the substrate; and transfer means for holding the substrate boat and transferring the substrate boat in the furnace axis direction of the furnace core tube. In a substrate heat treatment apparatus having a lid for closing an opening, the transfer means comprises a support for holding the substrate boat and a drive mechanism for driving and displacing the support, and the support is inserted through the support and relatively moved. In addition to forming a possible insertion hole, a lid transfer means for displacing the lid between an open position and a closed position is provided, and the substrate boat is moved by the transfer means in a state where the lid is in the closed position. By means of cooling position by means Place to be able to make up.

Further, in the substrate heat treatment apparatus according to the present invention, the cooling means is constituted by a first cooling means for absorbing radiant heat and a second cooling means for supplying cooling air.

[0011]

According to the structure of the substrate heat treatment apparatus according to the first aspect of the present invention, during normal heat treatment, the cover is moved to the closed position by the cover transfer means, and the substrate boat is heated by the heating means by the drive mechanism. To the position,
After the heat treatment, with the lid kept at the closed position, only the substrate boat is displaced to the cooling position by the cooling means by the drive mechanism, and the substrate is cooled in the furnace tube with the opening closed by the lid. be able to.

Further, according to the configuration of the substrate heat treatment apparatus of the second aspect of the invention, the cooling rate can be improved, unlike the conventional cooling chamber configuration.

[0013]

Next, an embodiment of the present invention will be described in detail with reference to the drawings.

<First Embodiment> FIG. 1 is an overall schematic vertical sectional view of a first embodiment of a substrate heat treatment apparatus, which is formed of a quartz material having an infrared transmittance so that the tube axis is oriented vertically. The furnace core tube 1 is provided, and an opening 2 is provided at the lower end side of the furnace core tube 1 in the tube axis direction. Through this opening 2, a substrate boat 3 holding a large number of substrates W. Is configured.

A hollow tubular body 4 is provided in the furnace core tube 1, and an annular gas supply path R is formed between the outer peripheral surface of the tubular body 4 and the inner peripheral surface of the furnace core tube 1. together with the gas introducing hole 5 is provided in an opening 2 side of the core tube 1, the supply means and the process gas supply means of the purge gas (not shown) is selectively connecting stub connected, N ₂ gas as a purge gas Ar gas or a process gas for reaction is introduced into the furnace tube 1.

Around the furnace core tube 1, a heater as heating means for heating a substrate W comprising a first heater 6a, a second heater 6b, and a third heater 6c short in the axial direction of the tube core. A unit 6 is provided.

A water cooling jacket 8 in which a cooling water supply pipe 7 is embedded is provided around the furnace core tube 1 between the heater unit 6 and the opening 2, and a water supply section 9 and a water tank 10 are provided. A drain 11 is connected to a water tank 10 via a water supply pipe 12 with a pump 11 interposed therebetween, and a drainage section 13 and a water tank 10 are connected via a drain pipe 15 with a cooler 14 interposed therebetween. The first cooling means is configured to cool the tube 1 and the substrates W.

The inner surface of the water-cooled jacket 8 is coated with a radiant heat absorbing material such as black alumite and the like.
And the substrate W can be efficiently absorbed.

In addition, the water cooling jacket 8
A casing 16 is provided so as to cover the heater unit 6, an inner peripheral surface of the casing 16 is covered with a heat insulating material 17, an exhaust port 18 is provided at an upper portion of the casing 16, and a lower portion of the water cooling jacket 8 is provided. An air supply port 19 for supplying cooling air is provided, and an air supply pipe 21 provided with an intake fan 20 is connected to the air supply port 19, and the furnace core tube 1 and the substrates W ...
The second cooling means is configured to cool the cooling water. Although not shown, heater support members that support the upper and lower portions of the heater unit 6 are provided integrally with the casing 16 at positions corresponding to the upper side and the lower side of the heater unit 6, respectively.

A structure comprising the first cooling means and the second cooling means is referred to as a cooling means in the first aspect. The invention according to claim 1 may include only one of the first cooling unit and the second cooling unit.

An exhaust pipe 22 is provided near the opening 2 of the furnace core tube 1 so as to communicate with the furnace core tube 1. A substrate boat 3 holding substrates W is inserted into the furnace core tube 1. When the process gas or the purge gas flows from the gas introduction hole 5 with the opening 2 closed by the lid 23, the process gas and the purge gas are discharged from the exhaust pipe 22. Exhaust means (not shown) is connected to the exhaust pipe 22.

The substrate boat 3 is made of a plurality of transparent quartz supporting columns for supporting the substrate provided at intervals in the circumferential direction. In this embodiment, for example, three columns 3c. Plate members 3a and 3b are integrally provided.

Each of the pillars 3c is formed with a substrate insertion groove (not shown) at a minute pitch in the longitudinal direction so that a required portion of the outer peripheral edge of the substrate W can be inserted and held at three points. .

On the lower plate 3a side, there is provided a heat insulating support member 26 in which heat insulating plates 25 are attached to the columns 24. Further, the pillars 27 are integrally extended below the heat insulating support member 26, and the pillars 27 are
Are formed so as to be relatively movable.

The lower ends of the columns 27 are integrally attached to a support member 29, and the support member 29 is rotatably attached to a support bracket 30 integrally attached to the lid 23. 31 and guide rod (not shown)
And an electric motor 32 provided on the support bracket 30 is connected to the first screw shaft 31 in an interlocking manner, and a transfer means is configured so that the substrate boat 3 can be driven up and down relative to the lid 23. I have. First screw shaft 31
, The electric motor 32, and the support member 29 on the first screw shaft 31.
Is referred to as a drive mechanism.

An elevating support arm 33 is attached to the support bracket 30.
Are attached integrally, and the lifting support arm 33 is
Attached to the second screw shaft 34 and a guide rod (not shown), a second electric motor 35 is interlockedly connected to the second screw shaft 34, and drives the lid 23 integrally with the support bracket 30. A lid transfer means is configured to be able to move up and down.

With the above arrangement, the support boat 30 is lowered to the lowermost position of the support bracket 30, and the support bracket 30 is lowered to the lowermost position of the second screw shaft 34. It can be placed outside the tube 1.

Then, by raising the support bracket 30, the opening 2 is closed by the lid 23, and then the columns 27... Are raised to the uppermost position of the support bracket 30, whereby the substrate boat 3 is heated. 6 and the heat treatment can be performed.

After the heat treatment is completed, the power supply to the heater unit 6 is stopped, and only the columns 27 are lowered to the lowermost position of the support bracket 30.
As shown in the overall schematic vertical cross-sectional view of FIG. 2, with the opening 2 closed by the lid 23, the substrate boat 3 is positioned at the cooling position by the first and second cooling means, and the cooling water and cooling water By supplying the air, the furnace core tube 1 and the substrates W can be cooled at a high speed.

In the prior art, heat was transferred from the high-temperature room to the low-temperature room because cooling was not taken into consideration. In the low-temperature room, the heat capacity of the heater was large, and only the cooling air could be sent. In other words, the main purpose was to maintain the low temperature chamber at a so-called buffer-like intermediate temperature for reducing thermal stress when slowly unloading (removing) from the high temperature chamber to the outside of the furnace, rather than at high speed cooling. It was only. In comparison with this, the cooling rate was greatly improved in the present invention.

FIG. 3 is a partially omitted cross-sectional view showing a first modification of the sealing structure between the column 27 and the lid 23. In a state surrounding each of them, a bottomed tubular cylinder 36 having a length sufficient to displace the substrate boat 3 from the above-described heating position to the cooling position is connected, and the support pillar 27 is fitted into each of the tubular bodies 36. In addition, a first magnet 37 is attached to the lower end.

On the other hand, a cylindrical body insertion hole 38 is formed in the support member 29 for inserting the cylindrical body 36.
The first magnet 37 is provided on the inner peripheral surface of the cylindrical insertion hole 38.
A second magnet 39 for supporting the substrate boat 3 by the magnetic force of the above is provided so as to securely seal the insertion holes 28 of the lid 23.

FIG. 4 is a cross-sectional view of a main part showing a second modification of the sealing structure between the column 27 and the lid 23. The inner peripheral surface of each of the insertion holes 28 of the lid 23 is shown in FIG. , A third magnet 40 and a magnetic fluid oil 41 held by the magnetic force are provided, and are configured to seal well with the insertion holes 28 of the lid 23.

FIG. 5 is a sectional view of a main part showing a third modification of the sealing structure between the support column 27 and the lid 23, and the inner peripheral surface of each of the insertion holes 28 of the lid 23. O-rings 42 are provided in two stages in the up-down direction so as to seal the insertion holes 28 of the lid 23 satisfactorily. A rod seal may be used instead of the O-ring.

<Second Embodiment> FIG. 6 is a cross-sectional view of a main part of a second embodiment of the substrate heat treatment apparatus.
A first annular member 43 formed of a heat-resistant material and having a circular opening slightly larger than the outer diameter of the furnace core tube 1 is attached to the lower end of the casing 16 between the lower portion of the casing 16 and the water cooling jacket 8. Below the first annular member 43, a second annular member 44 formed of a heat-resistant material and having a circular opening slightly larger than the outer diameter of the furnace core tube 1 is attached. The second annular member 43,
A heat insulating ceramic fiber cloth 45 is interposed between the inner peripheral surface of the furnace core 44 and the outer peripheral surface of the furnace core tube 1 so as to seal the heater unit 6 side and the water cooling jacket 8 side.

As shown in the plan view of FIG. 7 (a) and the perspective view of the main part of FIG. 7 (b), the first annular member 43 has a circumferential opening on its circular opening side. Eight openings 46 are formed at intervals, and the second annular member 4
4, eight openings 47 are formed at positions radially outward from the first annular member 43 at circumferentially spaced intervals, and each of the openings 47 is formed in a radial direction. A concave portion 48 is formed continuously on the inner side, and both openings 46... 47 are connected via the concave portion 48.

Heater support members 49 for supporting the lower portion of the heater unit 6 project radially outwardly from the openings 46 on the upper surface of the first annular member 43 at intervals in the circumferential direction. I have.

A check damper 50 made of a heat-resistant material is provided at each of the openings 47 of the second annular member 44 so as to be vertically swingable. When the cooling air is not supplied, it is closed by its own weight, so that hot air from the heater unit 6 does not escape to the water cooling jacket 8 side.

<Third Embodiment> FIG. 8 is an overall schematic longitudinal sectional view of a third embodiment of the substrate heat treatment apparatus. The difference from the first embodiment is as follows.

In other words, the substrate boat 3 is of a horizontal type in which the core axis direction of the furnace core tube 1 is oriented in the horizontal direction.
Are held in the insertion holes 28 of the two ceramic lids 23 by a support 52 (usually composed of two) that can move relatively horizontally. Reference numerals 53, 53 denote furnace core tube supporting members. In FIG. 8, FIGS.
The same reference numerals as those used above denote the same members having the same functions and functions as those described above, and a description thereof will be omitted.

<Fourth Embodiment> FIG. 9 is a partially omitted cross-sectional view of a main part of a fourth embodiment of a substrate heat treatment apparatus, and FIG. 10 is a side cross-sectional view of the main part. The configuration corresponding to the second embodiment is added, and the difference from the second embodiment is as follows.

Each of the first and second annular members 43 and 44 is deviated upward and downward by deviating from the middle position in the vertical direction, and is provided with six openings 46a... 47a and concave portions 48a.
Are formed, and in each of the openings 47a.
A check damper 50 is attached so as to be swingable around the upper axis, and a stopper 54 is provided at a lower portion of the check damper 50 to prevent the check damper 50 from swinging from the closed position to the water cooling jacket 8 side. When air is supplied, it is closed by its own weight when air for cooling is not supplied, so that hot air from the heater unit 6 does not escape to the water cooling jacket 8 side. In FIGS. 9 and 10, the same reference numerals as those used in FIGS. 1 to 5 denote the same members having the same functions and functions as those described above, and a description thereof will be omitted.

[0043]

As described above, according to the substrate heat treatment apparatus of the first aspect of the present invention, the cooling of the substrate after the heat treatment is performed in the furnace core tube closed with the lid, so that the atmospheric component Process contamination such as unexpected formation of a natural oxide film due to intrusion can be avoided and quality can be improved.

Further, according to the substrate heat treatment apparatus of the second aspect of the present invention, it is possible to avoid, for example, defects in aluminum wiring due to insufficient cooling rate.

[Brief description of the drawings]

FIG. 1 is an overall schematic longitudinal sectional view showing a first embodiment of a substrate heat treatment apparatus according to the present invention in a heating position.

FIG. 2 is an overall schematic longitudinal sectional view showing a state in a cooling position.

FIG. 3 is a partially omitted cross-sectional view of a main part showing a first modification of a seal structure between a column and a lid.

FIG. 4 is a sectional view of a main part showing a second modified example of the seal structure between the column and the lid.

FIG. 5 is a cross-sectional view of a main part showing a third modified example of the seal structure between the column and the lid.

FIG. 6 is a sectional view of a main part of a second embodiment of the substrate heat treatment apparatus according to the present invention.

7A is a plan view, and FIG. 7B is a perspective view of a main part.

FIG. 8 is an overall schematic longitudinal sectional view of a third embodiment of the substrate heat treatment apparatus according to the present invention.

FIG. 9 is a partially omitted cross-sectional view of a main part of a fourth embodiment of the substrate heat treatment apparatus according to the present invention.

FIG. 10 is a side sectional view of a main part.

FIG. 11 is an overall schematic vertical sectional view showing a conventional example of a substrate heat treatment apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Furnace core tube 2 ... Opening 3 ... Substrate boat 6 ... Heater unit as a heating means 23 ... Lid 27 ... Column 28 ... Insertion hole W ... Substrate

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical display location H01L 21/22 511 H01L 21/22 511A 21/31 21/31 F 21/324 21/324 D

Claims (2)

(57) [Claims] 1. A furnace core tube having an opening for inserting a substrate boat holding a substrate at one end side in the tube axis direction and introducing a gas into the furnace core tube, wherein the furnace core tube is provided around the furnace core tube. Heating means for heating the substrate, cooling means provided around the opening side of the furnace core tube in the tube axis direction relative to the heating means to cool the substrate, and the furnace core tube holding the substrate boat In a substrate heat treatment apparatus comprising: a transfer means for transferring in the tube axis direction; and a lid for closing the opening, the transfer means comprises a support for holding the substrate boat and a driving mechanism for driving and displacing the support. The cover body is formed with an insertion hole that can be relatively moved by inserting the support post, and a cover body transfer unit that displaces the cover body between an open position and a closed position is provided, and the cover body is closed. In the position Wherein the substrate boat is configured to be displaceable between a heating position by a heating means and a cooling position by a cooling means. 2. A substrate heat treatment apparatus according to claim 1, wherein said cooling means comprises a first cooling means for absorbing radiant heat and a second cooling means for supplying cooling air.