JPH11340237A - Substrate heating apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a substrate heating apparatus which is able to mount a substrate, such as a silicon wafer or glass on a susceptor and can transport the substrate, while keeping it at a constant temperature. SOLUTION: A susceptor is to be a two-body structure which is made up of an A block 1 as its central part and a B block 2 as its outer peripheral part. Temperature sensors 3 and 4 are built in the respective blocks. Thereby temperatures at points (a) and (b) and be separately measured, and by making different temperature controls to be carried out over the substrate central and outer-peripheral parts, the temperature of the substrate can be made uniform.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a substrate heating apparatus for uniformly heating and holding a substrate such as a silicon wafer or glass to a predetermined temperature before or during film formation in a thin film forming apparatus.

[0002]

2. Description of the Related Art FIG. 5 shows an example of a conventional thin film forming apparatus. The substrate 12 is placed in contact with the susceptor 11, and the susceptor 11 and the substrate 1
A removable mask 13 is arranged on 2. The exposed portion on the upper surface of the susceptor 11 is entirely covered with the substrate 12 and the mask 13. The substrate 12 heated to a certain temperature is transported together with the susceptor 11 in the direction shown in the drawing to a connected film forming chamber for film formation.

In the film forming chamber, a load chamber 21, a reaction chamber 22, and an unload chamber 23 are connected by a connecting duct 24. In the load chamber 21, lamp heaters 25 and 26 are installed above and below the substrate 12. I do. The substrate 1 is placed in the reaction chamber 22.
2 is provided with a lamp heater 27 on the lower side, and an electrode 28 on the upper side.
The electrode 28 is further connected to an RF generator 29 and connected to a predetermined gas cylinder or the like via a valve 30. The load chamber 21, the reaction chamber 22, and the unload chamber 23 all communicate with the pump 31 and the atmosphere via the valve 30. The lamp heaters 25 and 27 are connected to the susceptor 11.
The lamp heater 26 is located above the substrate 12.

FIG. 6 shows a detailed view around the substrate 12. As shown in FIG. The mask 13 is provided for the purpose of preventing a film from being formed on the susceptor 11 other than the substrate 12 at the time of film formation. Since the mask 13 needs to be replaced, it can be removed. Here, each of the lamp heaters 25 to 27 is a mechanism including a plurality of rod-shaped lamps whose output can be independently controlled one by one at right angles to the substrate transport direction. Regarding the heating mechanism, the upper lamp heater 26 heats the substrate 12 by direct radiant heat. The lower lamp heaters 25 and 27 heat the susceptor 11 from below, and conduct the temperature rise of the susceptor 11 to the substrate 12. Susceptor 11
Are embedded with temperature sensors 41 arranged in the same direction as the lamp.

[0005] The temperature control method in this system is based on the susceptor 1
(1) When the temperature of the temperature sensor 41 embedded in the inside is read, the output of the lamp heater 25 for increasing the temperature of the portion is adjusted, the output of the lamp heater 25 is increased until the temperature reaches a predetermined temperature, and the predetermined temperature is maintained. If the temperature is higher or lower than the other parts, the lamp heater 25 of the corresponding part
By controlling the output, the temperature of the entire susceptor 11 is controlled, and finally the temperature of the substrate 12 is made constant over the entire surface. The susceptor 11 also has a role of placing the substrate 12 on the upper part, moving along the guide rod 42 provided along the traveling direction, and transporting the substrate 12 to the reaction chamber 22 and the unloading chamber 23. In such a configuration, when the transfer mechanism moves from the load chamber 21 to the reaction chamber 22 connected by the connection duct 24 while the substrate 12 is placed on the susceptor 11, the lamp heater 25 that must be controlled also moves sequentially. Will be done. Basically, the temperature of the susceptor 11 is controlled by controlling the output of the lamp heater 25 immediately below the place where the temperature control is required, and the surface temperature of the substrate 12 is kept constant.

FIG. 7 shows a result of a temperature distribution on the substrate 12 when the substrate 12 is heated by the conventional apparatus. In FIG.
Although the temperature around the substrate 12 is lower than that inside, the above-mentioned mask 13 has
This is because they take away heat from 2. This is also because radiant heat from the upper lamp heater 26 is shielded by the mask 13. However, since a lamp for controlling the temperature is provided in the form of a rod, it is difficult to raise the temperature only around the substrate 12, which is a low temperature portion. Further, the susceptor 11 is connected to the substrate 12 from the load chamber 21 to the reaction chamber 22.
Therefore, the shape of the lamp cannot be adjusted to the temperature distribution. In order to make the temperature of the substrate uniform, Japanese Patent Application Laid-Open No. 5-55145 discloses that a radiation shielding ring is provided between the substrate and the heater to limit the radiant heat from the heater in the peripheral portion of the substrate where the temperature is high. It is described that the substrate temperature is thereby made uniform.

[0007]

However, in the above configuration, when the temperature at the center of the substrate is high, the high temperature at the center of the substrate cannot be suppressed. In particular, it is not possible to keep the temperature of the substrate uniform by suppressing the temperature at the center of the substrate while moving the substrate. The present invention has been made in view of the above problems, and has as its object to provide a substrate heating apparatus capable of setting a substrate on a susceptor and transporting the substrate while maintaining a uniform temperature.

[0008]

In order to solve the above-mentioned problems, a substrate heating apparatus according to the present invention is characterized in that a susceptor that holds and heats conductively a substrate is provided at a position where one substrate is heated differently. And the susceptor having a structure comprising: Further, since the different position portions are divided from each other, each of the different position portions can be easily manufactured. Furthermore, since at least two of the position portions, which are the divided structures, have different shapes, a susceptor having a shape corresponding to the temperature distribution of the substrate can be obtained.

In addition, at least one of the divided portions has a structure surrounding the periphery of at least one of the divided portions, so that the temperature is different between the central portion and the peripheral portion of the substrate. The temperature distribution can be made uniform. Further, since at least two of the position portions, which are the divided structures, are made of different materials, the thermal conductivity of the susceptor can be made different depending on the position portions. Also,
At least one of the position portions, which is a divided structure, is movable so that contact or non-contact with the substrate can be selected independently of at least one of the other portions, so that heat transfer from the susceptor at each position portion can be achieved. The amount can be different.

[0010] Further, since at least two of the divided portions having the divided structure are provided with a thermometer, the temperature of each of the divided portions of the susceptor can be measured. Temperature can be measured indirectly. Further, since at least two of the position portions are made of different materials, the thermal conductivity of the susceptor can be made different depending on the position portions. In addition, the susceptor has a region that continuously changes from one material to another material depending on the position, so that the substrate temperature can be more finely uniformed in a region where the temperature greatly changes depending on the position. .

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a diagram showing a configuration of a main part of a substrate heating apparatus according to an embodiment of the present invention. In the present embodiment, the susceptor is divided, and the shape of the division is in accordance with the concentric temperature distribution and along the distribution state. More specifically, the divided shape has a two-body structure of an A block 1 at the center and a B block 2 at the outer periphery. Then, as shown in FIG. 6, conventionally, the temperature sensor 41 is measured as an average temperature in a shape along a lamp, but the temperature sensors 3, 4 are incorporated in each of the divided blocks as shown in FIG. This makes it possible to individually measure the temperatures at points a and b, which could not be measured conventionally.

In the thin film forming apparatus, the substrate 12 carried into the load chamber 21 manually or automatically is heated to a certain temperature before film formation, and is maintained at the same temperature. Next, the substrate 12 is transferred to the reaction chamber 22 connected by the connection duct 24, and after forming a thin film, transferred to the unloading chamber 23 connected by the connection duct 24. Here, the substrate 12
Temperature uniformity is required in the load chamber 21 and the reaction chamber 2
Within 2. As in the conventional case, the lower lamp heater 2 that heats the susceptor 11 by radiant heat and heats the substrate 12 by conduction heat from the susceptor 11 is provided in the load chamber 21.
5 is installed. An upper lamp heater 26 for directly heating the substrate 12 by radiant heat is provided. The lamps of the lamp heaters 25 to 27 are individually shaped as shown in FIG. 8, and they are arranged side by side at right angles to the transport direction of the substrate 12. FIG. 9 shows the output characteristics of the lamp. Here, the effective irradiation width is X in the figure. This indicates that the lamp has a uniform output in the longitudinal direction. The substrate 12 is set in the load chamber 21 manually or automatically. The set is set so that the substrate 12 is sandwiched between the mask 13 and the susceptor 11 as shown in FIG. That is, the substrate 12 is inserted and placed between the separated susceptor 11 and the mask 13 when the substrate 12 is carried into the load chamber 21. Substrate 12
Is performed by lamp heaters 25 and 26. The susceptor 11 heated by the radiant heat of the lamp heater 25 heats the substrate 12 placed in contact therewith by heat conduction. At this time, since the substrate temperature near the portion covered by the mask 13 becomes low as shown in FIG. 7, the susceptor 11 is divided as shown in FIG. The temperature sensors 3 and 4 for measuring the temperature are also arranged in accordance with the susceptor division.

Next, as a method of making the temperature distribution uniform, as a first method, the members of the inner A block 1 are replaced with the outer B block.
By selecting a material having a low thermal conductivity from the members of the block 2, it is possible to maintain a uniform substrate temperature distribution even when the amount of heat radiation from the lamp heater 25 to each of the blocks 1 and 2 is the same. Can be. As a second method, a vertical drive mechanism is provided on the inner A block 1 as shown in FIG. 3, the block temperature is managed by a temperature sensor, and the inner A block 1 is driven up and down so that the substrate temperature becomes constant. . That is, when the substrate temperature becomes high, the A block 1 is lowered, the substrate 12 and the susceptor 11 are not in contact with each other, a gap is provided, and heating by heat conduction is temporarily stopped. For this reason, the susceptor 11 is carried out to the reaction chamber 22 via the connection duct 24 by the transfer mechanism while keeping the substrate temperature uniform. During this time, the surface temperature of the substrate 12 can be kept uniform.

As another embodiment, as shown in FIG. 4, the susceptor 11 may have a shape in which small parts in a lattice form are connected vertically and horizontally. The substrate temperature can be made uniform by arbitrarily selecting the materials of these components according to the temperature distribution of the substrate 12. That is, the susceptor 11 in which members made of materials having different thermal conductivity are combined in accordance with the temperature distribution is assembled.
Therefore, no matter what the temperature distribution of the substrate 12 is, it is possible to deal with it by replacing small components. All the mechanisms and specifications other than those around the susceptor are common to the above embodiment. Furthermore, the present invention is not limited to the above embodiment.

The susceptor may be an integral structure instead of a divided structure. In this case, the material is made different depending on the position where the conductive heating is performed while having an integrated structure, so that the conductivity is different depending on the position and the substrate temperature is made uniform.
Further, by continuously changing the material, the substrate temperature can be more finely uniformed in a region where the temperature greatly changes depending on the position. Further, the susceptor may have a built-in heater. In this case, the lower lamp heaters 25 and 27 are not required.

[0016]

As described above, according to the present invention, the temperature of the substrate in the thin film forming apparatus can be kept constant. That is, the non-uniformity of the thin film due to the non-uniformity of the substrate temperature generated by the conventional thin film forming apparatus is eliminated. As a result, it is possible to contribute to the reduction of defects and to improve the performance of the entire apparatus. Also,
Since the present invention is effective not only in a thin film forming apparatus but also in an apparatus that raises and maintains a substrate to a certain temperature in general,
Applicable to a wide range of devices.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a substrate heating device according to an embodiment of the present invention.

FIG. 2 is a layout diagram around a substrate heating device according to an embodiment of the present invention.

FIG. 3 is an explanatory diagram of a substrate heating device driving mechanism according to an embodiment of the present invention.

FIG. 4 is a diagram showing a configuration of a substrate heating device according to another embodiment of the present invention.

FIG. 5 is an explanatory view of a thin film forming apparatus.

FIG. 6 is an explanatory diagram around a conventional susceptor.

FIG. 7 is a diagram showing an example of a temperature distribution on a substrate.

FIG. 8 is a diagram showing details of a lamp.

FIG. 9 is a diagram showing output characteristics of a lamp.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 A block 2 B block 3, 4 Temperature sensor 11 Susceptor 12 Substrate 13 Mask 21 Load chamber 22 Reaction chamber 23 Unload chamber 24 Connection duct 25, 26, 27 Lamp heater 28 Electrode 29 RF generator 30 Valve 31 Pump 41 Temperature sensor 42 Guide Rod

Claims (9)

[Claims] 1. A substrate heating apparatus, wherein a susceptor for holding a substrate and conducting and heating the substrate includes the susceptor having a structure including different conductive heating positions for one substrate. 2. A substrate heating apparatus according to claim 1, wherein said different position portions are divided from each other. 3. The at least two position portions which are divided structures have different shapes.
The substrate heating apparatus according to any one of the preceding claims. 4. The substrate heating apparatus according to claim 3, wherein at least one of the divided portions has a structure surrounding at least one of the divided portions. 5. The apparatus according to claim 2, wherein at least two of said position portions having a divided structure are made of different materials.
5. The substrate heating apparatus according to any one of items 1 to 4. 6. The apparatus according to claim 2, wherein at least one of the position portions, which is a divided structure, is movable so as to select contact / non-contact with the substrate independently of at least one other. 6. The substrate heating apparatus according to any one of claims 1 to 5. 7. The substrate heating apparatus according to claim 2, wherein at least two of the position portions having a divided structure include a thermometer. 8. The substrate heating apparatus according to claim 1, wherein at least two of said position portions are made of different materials. 9. The substrate heating apparatus according to claim 8, wherein the susceptor has a region that changes from one material to another material depending on the position.