JP3443779B2 - Heat treatment equipment for semiconductor substrates - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming an oxide film, a polycrystalline silicon film, etc. on a semiconductor substrate in a manufacturing process of a large-scale integrated circuit, and for forming an active film after ion implantation. The present invention relates to an apparatus used when heat-treating a semiconductor substrate, such as heat treatment for the purpose of heat treatment, and particularly to a heat treatment apparatus and a heat treatment method suitable for performing heat treatment while keeping the in-plane temperature of the semiconductor substrate uniform. 2. Description of the Related Art Conventionally, as described in Japanese Patent Application Laid-Open No. 55-150238 or Japanese Patent Application Laid-Open No. 56-80138, a semiconductor substrate is scanned while being irradiated with an energy beam, and the entire surface is scanned. Heat treatment was performed. However, in this heat treatment, the entire surface of the semiconductor substrate cannot be heat-treated at a uniform temperature.
As described in Japanese Patent Application Laid-Open No. 293622/1993, the semiconductor substrate during the heat treatment was rotated. In the above prior art, it is necessary to rotate the semiconductor substrate in order to uniformly heat the semiconductor substrate. As a result, a rotation mechanism of the semiconductor substrate is required, and there has been a problem that the device configuration is complicated. In particular, when the periphery of the substrate during the heat treatment is in a reduced pressure state, air or the like leaks from the rotation mechanism into the heat treatment apparatus, and there is a problem that the heat treatment cannot be performed in a clean atmosphere. An object of the present invention is to provide an apparatus and a method for heat treating a semiconductor substrate which can realize a uniform in-plane temperature distribution without requiring a rotation mechanism of the semiconductor substrate. Another object of the present invention is to stably operate a heat treatment apparatus that achieves the above object. In order to achieve the above object, the present invention provides a heat treatment apparatus comprising a semiconductor substrate held therein and at least a portion of the substrate facing a surface to be heat treated formed by a light transmitting member. In a semiconductor substrate heat treatment apparatus including a container and a light heating mechanism for irradiating the semiconductor substrate with light to heat the semiconductor substrate, the heat treatment apparatus is provided between the light heating mechanism and the semiconductor substrate.
A scattering plate for scattering the irradiation light from the light heating mechanism.
The semiconductor plate holding the scattering plate in the heat treatment container.
It is characterized in that a drive mechanism for moving in a direction in-plane temperature distribution of the body substrate is made uniform. According to the present invention, there is provided a heat treatment container in which a semiconductor substrate is held and at least a portion of the substrate facing a heat treatment surface is formed of a light transmitting member, and the semiconductor substrate is irradiated with light and heated. A heat treatment apparatus for a semiconductor substrate having a light heating mechanism, wherein a driving mechanism for moving the light heating mechanism in a direction in which an in-plane temperature distribution of the semiconductor substrate held in the heat treatment container is uniformed is provided. It is a feature. In the above heat treatment apparatus for a semiconductor substrate,
The direction in which the light heating mechanism is moved by the driving mechanism is parallel to the semiconductor substrate surface. here,
The light heating mechanism may be one in which sub-several lamps are arranged in parallel at a constant pitch, or one that includes an arc lamp and a scattering plate disposed between the arc lamp and the semiconductor substrate. The direction in which the light heating mechanism is moved by the drive mechanism may be a direction in which the semiconductor substrate rotates about the central axis of the semiconductor substrate as the rotation axis. In this case, it is preferable that the light heating mechanism is a heating light source that is divided into a plurality of equally divided portions around the upper side of the semiconductor substrate. In the above-mentioned semiconductor substrate heat treatment apparatus, it is preferable that a shielding member for shielding radiant heat from the light heating mechanism is provided between the light heating mechanism and the driving mechanism. Here, the shielding member is preferably provided with a cooling means. Further, the present invention provides a heat treatment container in which a semiconductor substrate is held and at least a portion of each substrate facing a surface to be heat treated is formed of a light transmitting member, and the semiconductor substrate is irradiated with light and heated. In a heat treatment apparatus for a semiconductor substrate provided with a light heating mechanism, the heat treatment container comprises a support means for supporting the two semiconductor substrates in parallel and supporting the heat treatment surfaces with the surfaces to be heat treated outside each other. A pair of light heating mechanisms for heating the respective semiconductor substrates, and a drive mechanism for moving the light heating mechanism while maintaining an interval with the semiconductor substrate held in the heat treatment container. . The present invention also relates to a method of heat treating a semiconductor substrate, wherein the semiconductor substrate is held in a heat treatment container, and the semiconductor substrate is irradiated with light by a light heating mechanism for heat treatment. The heat treatment is carried out while moving the light heating mechanism while maintaining the distance between. By moving the light heating mechanism provided outside the heat treatment vessel while maintaining the distance from the semiconductor substrate, the semiconductor substrate is uniformly irradiated with the heating light, so that the semiconductor substrate is heated. The temperature distribution becomes uniform. As a result, a substrate rotating mechanism is not required. By providing a shielding means such as a metal plate between the light heating mechanism and the driving mechanism, heat radiation from the light heating mechanism is less likely to reach the driving mechanism of the heating lamp mechanism by the metal plate. As a result, the drive mechanism can operate stably without increasing the temperature. An embodiment of the apparatus for heat treating a semiconductor substrate according to the present invention will be described below in detail with reference to the drawings. FIG. 1 is a sectional view of a heat treatment apparatus according to the present embodiment, and FIG. 2 is a perspective view of the same apparatus. The silicon substrate 101 is a silicon single crystal substrate having a diameter of 200 mm, a plane orientation (100), a boron dopant, and a resistivity of 10 Ω · cm. The silicon substrate 101 is held by a silicon substrate support mechanism 102 in a heat treatment container 103 made of quartz. A heating lamp mechanism 104 is provided outside the heat treatment vessel 103. The heating lamp mechanism 104 is provided with 20 lamps 105 at a pitch of 13 mm. The pitch of the lamp 105 is 1 to 100.
mm. The lamp 105 has a light emission length of 250 m
m, 480 V, 6 kW tungsten halogen lamp. The distance between the silicon substrate 101 and the center of the lamp 105 is 25 mm in this embodiment. Silicon substrate 10
1 is heated by the heating lamp mechanism 104. The temperature of the silicon substrate 101 is measured by the temperature measuring mechanism 109. In this embodiment, a radiation thermometer is used as the temperature measuring mechanism 109. The heating lamp mechanism 104 is connected to a driving mechanism 106 by a connecting rod 110, and the heating lamp mechanism 104 is driven so as to periodically move in a direction parallel to the surface of the silicon substrate 101 on the substrate 101. The movement width of the heating lamp mechanism 104 is 25 mm, and the cycle is 1 second.
This movement width can be adjusted between 1 and 100 mm, and the cycle can be adjusted between 0.1 and 60 seconds. Note that the optimum movement width depends on the relationship between the diameter of the silicon substrate 101 and the light emission length of the lamp 105 and the distance between the silicon substrate 101 and the lamp 105. The driving mechanism 106 is connected to the housing 112 by a fixing mechanism 111. By such parallel movement of the heating lamp mechanism 104, it is possible to prevent variations in heating due to variations in layout when the lamps 105 are installed at a pitch of 20 mm and 13 mm as described above. An atmosphere gas inlet 107 is provided inside the heat treatment vessel 103. Atmospheric gas is exhaust system 1
08 is exhausted. In this embodiment, a mixed gas of hydrogen gas and oxygen gas was used as the atmosphere gas, and a dry pump was used for exhaust. FIG. 3 and FIG.
FIG. 5 is a diagram showing the in-plane distribution of the thickness of an oxide film formed on the surface of a silicon substrate when the substrate is processed at a temperature of ℃. Ellipsometry was used for the measurement. When the heating lamp mechanism 104 was not moved in parallel (FIG. 3), an oxide film thickness distribution reflecting the arrangement state of the lamp 105 was obtained. On the other hand, the heating lamp mechanism 104 is moved by the driving
When it was moved in parallel at a cycle of 1 mm with a cycle of 1 mm (FIG. 4), a uniform oxide film thickness distribution was obtained. Next, another embodiment of the present invention will be described. FIG. 5 is a sectional view of the heat treatment apparatus used in the present embodiment. The silicon substrate 101 has a diameter of 100 mm and a plane orientation (10
0), a boron single-crystal silicon substrate having a resistivity of 10 Ω · cm. The silicon substrate 101 is held by a silicon substrate support mechanism 102 in a heat treatment container 103 made of quartz. A heating lamp mechanism 104 is provided outside the heat treatment container 103. The heating lamp mechanism 104 is provided with five lamps 105 at a pitch of 13 mm. Lamp 10
Reference numeral 5 denotes a tungsten halogen lamp having an emission length of 250 mm, 480 V, and 6 kW. The four heating lamp mechanisms 104 are provided around the heat treatment container 103. The silicon substrate 101 is heated by the heating lamp mechanism 104. The temperature of the silicon substrate 101 is measured by the temperature measuring mechanism 109. All four heating lamp mechanisms 104 are connected to the driving mechanism 106 by connecting rods 110, and all four heating lamp mechanisms 104 are simultaneously connected to the silicon substrate 101.
Periodically rotate around the central axis of the. The rotation angle is 30
The cycle is 2 seconds. The rotation angle can be adjusted between 1 and 270 degrees, but is set to 30 degrees in this embodiment so that the power cable connected to the heating lamp mechanism 104 is not twisted. As a result of forming an oxide film on the silicon substrate 101 in the same manner as in the above-described embodiment, the oxidation treatment having the uniform oxide film thickness distribution shown in FIG. 4 was also possible in this embodiment. Next, another embodiment of the present invention will be described. FIG. 6 is a cross-sectional view of an apparatus used for stably operating the heat treatment apparatus shown in FIG. The basic structure is the same as that of the apparatus shown in FIG. 1, but a metal plate 201 is provided between the heating lamp mechanism 104 and the driving mechanism 106.
FIG. 7 shows a schematic structure of the metal plate 201. This metal plate 201 is made of copper with a thickness of 2 mm. A hole 202 is formed in the metal plate 201 so that the connecting rod 110 can be moved. By installing the metal plate 201, the drive mechanism 106 became less susceptible to radiant heat from the heating lamp mechanism 104, and the drive mechanism 106 operated stably without thermal degradation. Further, by installing the water cooling pipe 203 on the metal plate 201 as shown in FIG. 8, the drive mechanism 106 can operate for a longer time. By using a gas containing silicon such as a monosilane gas as an atmospheric gas, it is of course possible to form a polycrystalline silicon film, a silicon epitaxial film, a silicon nitride film and the like. The present invention is also effective for simple heat treatment such as activation treatment after ion implantation treatment. Next, another embodiment of the present invention will be described. FIG. 9 is a cross-sectional view of the device used in this embodiment, and FIG. 10 is a perspective view of the device. The silicon substrate 101 has a diameter of 200 m
m, plane orientation (100), boron dopant, resistivity 10Ω
cm of silicon single crystal substrate. Silicon substrate 101
Is held by a silicon substrate support mechanism 102 in a heat treatment vessel 103 made of quartz. An arc lamp 120 is provided outside the heat treatment container 103. The output of the arc lamp 120 is 5 kW. Between the arc lamp 120 and the silicon substrate 101, there is provided a scattering plate 130 for scattering the irradiation light from the arc lamp 120. The scattering plate 130 is connected to the driving mechanism 106 by a connecting rod 110, and the scattering plate 130 is periodically driven in a direction parallel to the substrate surface of the silicon substrate 101. Movement width is 1 to 10
Although it can be adjusted between 0 mm, in the present embodiment, it was set to 25 mm. Further, the period can be adjusted between 0.1 and 60 seconds, but is set to 1 second in this embodiment. As a result of forming an oxide film on the silicon substrate 101 in the same manner as in the above-described embodiment, the oxidation treatment having the uniform oxide film thickness distribution shown in FIG. 4 was also possible in this embodiment. Next, another embodiment of the present invention will be described. FIG. 11 is a sectional view of the device used in this embodiment. Each of the two silicon substrates 101 is a silicon single crystal substrate having a diameter of 200 mm, a plane orientation (100), a boron dopant, and a resistivity of 10 Ω · cm. These two silicon substrates 101
Are held in parallel in a quartz heat treatment vessel 103 by a silicon substrate support mechanism 102. A pair of heating lamp mechanisms 104 are provided on both outer sides of the heat treatment vessel 103. The lamp 10 is connected to both heating lamp mechanisms 104.
5 are installed. The pitch between the lamps is 1-1
Although it can be adjusted between 00 mm, it is 13 mm in this embodiment. The lamp 105 has a light emission length of 250 mm, 480 V, 6 k
W is a tungsten halogen lamp. The distance between the silicon substrate 101 and the center of the lamp 105 is 25 mm. The two silicon substrates 101 are heated by respective heating lamp mechanisms 104. Heating lamp mechanism 104
Are connected to the driving mechanism 106 by connecting rods 110, respectively.
01 is driven periodically in the direction parallel to the substrate surface. The moving width can be adjusted in the range of 1 to 100 mm.
mm. Although the period can be adjusted between 0.1 and 60 seconds, it is set to 1 second in this embodiment. In the present embodiment, the two driving mechanisms 106 are independent of each other, but the heating lamp mechanism 104 may be driven at a different cycle or by synchronizing the movement cycle. As a result of forming an oxide film on the silicon substrate 101 in the same manner as in the above-described embodiment, the oxidation treatment having a uniform oxide film thickness distribution shown in FIG. At the same time. According to the present invention, the light heating mechanism installed outside the heat treatment vessel is moved in parallel or in rotation while maintaining the interval with respect to the silicon substrate surface, so that the light heating can be performed without rotating the semiconductor substrate. The heating light from the mechanism is uniformly applied to the semiconductor substrate, and the temperature distribution of the semiconductor substrate becomes uniform. As a result, there is an effect that a complicated rotation mechanism of the silicon substrate becomes unnecessary. By providing a shielding means such as a metal plate between the light heating mechanism and its driving mechanism, radiant heat from the light heating mechanism is shielded by the metal plate and hardly reaches the driving mechanism. As a result, the drive mechanism is not heated, and has an effect that it can operate stably.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a sectional view of a heat treatment apparatus for explaining one embodiment of the present invention. FIG. 2 is a perspective view of the apparatus of FIG. FIG. 3 is a diagram showing a distribution of the thickness of an oxide film formed on the surface of the silicon substrate in the plane of the silicon substrate when the heating lamp mechanism is not moved in parallel. FIG. 4 is a diagram showing the distribution of the thickness of an oxide film formed on the surface of the silicon substrate in the plane of the silicon substrate when the heating lamp mechanism is moved in parallel. FIG. 5 is a sectional view of a heat treatment apparatus for explaining another embodiment of the present invention. FIG. 6 is a cross-sectional view of a heat treatment apparatus according to another embodiment of the present invention, which stably operates the apparatus. FIG. 7 is a perspective view showing a schematic structure of a metal plate. FIG. 8 is a perspective view showing a schematic structure of a water-cooled metal plate. FIG. 9 is a sectional view of a heat treatment apparatus for explaining another embodiment of the present invention. FIG. 10 is a perspective view of the device of FIG. 9; FIG. 11 is a sectional view of a heat treatment apparatus for explaining another embodiment of the present invention. DESCRIPTION OF SYMBOLS 101 silicon substrate 102 silicon substrate support mechanism 103 heat treatment vessel 104 heating lamp mechanism 105 lamp 106 drive mechanism 107 atmosphere gas introduction hole 108 exhaust mechanism 109 temperature measuring mechanism 110 connecting rod 120 arc lamp 130 scattering plate 201 metal plate 202 Groove 203 water cooling pipe

   ────────────────────────────────────────────────── ─── Continuation of front page       (56) References JP-A-3-276625 (JP, A)                 JP-A-5-5182 (JP, A)                 JP-A-61-229811 (JP, A)                 JP-A-63-227014 (JP, A)

Claims (1)

(57) Claims 1. A heat treatment container which holds a semiconductor substrate inside and at least a portion of the substrate facing the surface to be heat treated is formed of a light-transmitting member. In a heat treatment apparatus for a semiconductor substrate having a light heating mechanism for irradiating and heating, a scattering plate provided between the light heating mechanism and the semiconductor substrate to scatter irradiation light from the light heating mechanism; the heat treatment apparatus of a semiconductor substrate, characterized in that a drive mechanism for moving in a direction in-plane temperature distribution of the semiconductor substrate held the scattered plate into the heat treatment container is made uniform.