JPH0737669B2 - Heater for CVD 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 low pressure CVD apparatus for depositing a tungsten film or a silicon film on the surface of a wafer or the like, and more particularly to the structure of a heater in a rapid heating type CVD apparatus using a lamp as a heating source. .

[0002]

2. Description of the Related Art Conventionally, a rapid heating type C using a lamp as a heating source
As a VD device, an object to be heated is supported by a ring-shaped holder arranged in a decompression chamber, a lamp unit of a heating lamp is arranged so as to face the object to be heated, and heat rays emitted from the lamp unit are heated. What is configured to heat an object to be heated to 600 to 1000 ° C. by acting on an object, and to supply a processing gas into a decompression chamber to form a metal thin film on the surface of the object to be heated. It is provided.

Since a CVD apparatus is required to uniformly heat an object to be heated, a lamp unit conventionally used as a heating source for a CVD apparatus is shown in FIG. 4 (A) or FIG. 4 (B). Things are known. As shown in FIG. 4 (A), the inner surface (51) of the lamp housing (50) is formed into a curved surface, and a plurality of straight tube halogen lamps are formed corresponding to the curved surface.
(52) are arranged in parallel so that the heat ray emitted from the lamp unit is formed into a parallel light flux. In addition, as shown in FIG. 4 (B), a plurality of semi-cylindrical concave fitting portions (53) are formed in parallel on the inner surface (51) of the lamp housing (50), and the concave fitting portions (53) are directly connected to the concave fitting portions (53). The tube halogen lamp (52) is arranged so that the heat ray emitted from the lamp unit is formed into a parallel light flux.

[0004]

In order to improve the reflection efficiency, the lamp housing of this type of device has its inner surface finished as a mirror surface, and the inner surface is gold-plated so that the mirror surface does not become cloudy. In the above lamp housing, since the curved surface portion is formed, it is difficult to manufacture the lamp housing, and it is difficult to apply uniform gold plating. Further, since the object to be heated such as a wafer or a glass substrate to be processed by the CVD device has large heat radiation from the peripheral portion, the heat distribution in the object to be heated becomes a middle-high parabolic shape in the central part. For this reason, in the conventional lamp unit, there is also an inconvenience that the output of each lamp has to be zone-controlled. The present invention has been made in view of such a point, and an object thereof is to provide a heating device capable of uniformly heating an object to be heated.

[0005]

In order to achieve the above-mentioned object, according to the present invention, the inner wall surface of the lamp unit is constituted by a flat surface plated with gold, and a plurality of straight tube lamps are arranged in parallel in the lamp unit. By arranging the lamp rows configured in this way in multiple stages, the lamp rows located above and below are positioned so that the straight tube lamps intersect with each other, and the arrangement pitch of the straight tube lamps in each lamp row is rough in the central part. The feature is that they are arranged so that

[0006]

In the present invention, since the inner wall surface of the lamp unit is constituted by a gold-plated flat surface, the manufacture of the lamp housing and the gold plating can be performed easily and with high precision. Further, a plurality of straight lamps are arranged in parallel in the lamp unit to arrange a plurality of lamp rows, and the upper and lower lamp rows are positioned so that the straight lamps cross each other. Since the arrangement pitch of straight tube lamps in the lamp row is arranged so that the center part becomes coarse, it is possible to prevent the temperature of the heated object from becoming too high without controlling the output of each lamp individually. To prevent this, uniformly heat the entire object to be heated.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The drawings show an embodiment of the present invention. FIG. 1 is a bottom view showing a lamp arrangement in a lamp unit, and FIG. 2 is a sectional view of a chamber portion of a CVD apparatus.

In this CVD apparatus, a lamp unit (2) is arranged above the decompression chamber (1), and heat rays are supported from the lamp unit (2) in the decompression chamber (1) with its surface facing downward. To be heated such as wafer substrate (3)
The object to be heated (3) is heated from the back side by irradiating the surface of the object, and a processing gas such as silane gas is jetted and supplied from the lower side into the decompression chamber (1) to supply the object to be heated (3). This is a rapid heating type CVD device configured to form a thin film on the surface.

The inside of the decompression chamber (1) is divided into upper and lower chambers by a quartz partition wall (4) formed in the shape of a bowl.
There is an opening (5) at the top of (4). Then, a ring-shaped holder for supporting the object to be heated (3) in the opening (5)
(6) is installed stably. This Ring Holder (6)
Is made of a heat-resistant material such as quartz, and by mounting the object to be heated (3) with the surface (treated surface) facing downward,
The surface of the object to be heated (3) supported by the ring-shaped holder (6) is exposed to the lower room defined by the partition wall (4).

A partition in the decompression chamber (1)
An opening (8) for supplying / discharging the object to be heated (3) is provided in the chamber peripheral side wall in the room (7) located above (4), and this opening (8) is provided to the object to be heated (3). The transport device (9) is moved in and out. In addition, an introduction path (10) for introducing a purging gas such as nitrogen or hydrogen and an exhaust path for discharging the indoor gas to the outside are connected to the room (7) located above the partition wall (4). There is.

On the other hand, the partition wall (4) in the decompression chamber (1)
An insertion opening (13) for an object-to-be-heated fitting (12) for guiding and mounting the object-to-be-heated (3) on the ring-shaped holder (6) on the peripheral wall of the chamber in the room (11) located below Is opened, and the article-to-be-heated attachment (12) is attached to the insertion port (13). This heating object mounting tool (12) has a rod end formed on a ring portion (14), and pins (15) are vertically formed on the ring portion (14) at appropriate intervals in the circumferential direction. Pin (1
The upper end of 5) is the object support base of the ring-shaped holder (6)
It is attached to the hole formed in part (17) so that it can move back and forth.
Further, the article-to-be-heated fitting (12) is moved up and down by the operation of the lifting mechanism (16) to load the article-to-be-heated (3) carried into the upper chamber (7) by the article-to-be-heated conveying device (9). The ring-shaped holder (6) is positioned and mounted, or is transferred from the ring-shaped holder (6) to the heated object transfer device (9). Also, this partition
A chamber (11) located below (7) is connected to a supply passage (18) for a processing gas such as silane gas and an exhaust passage, and the tip of the reaction gas introduction passage (18) is a ring-shaped holder. Below the portion (6), there is an opening at an appropriate position where the ejected reaction gas can contact the surface of the article to be heated (3).

Therefore, the decompression chamber of this embodiment
In (1), the room (11) located below the partition (4) becomes the reaction chamber, and the room (7) located above the partition (4) becomes the heating chamber. During the film forming work, the internal pressure on the heating chamber (7) side is reduced to about 1.0 to several tens Torr, and
The internal pressure on the reaction chamber (11) side is reduced to about 0.1 to 10 Torr so that the heating chamber (7) and the reaction chamber (11) have a difference in internal pressure. In this way, by making a pressure difference between the internal pressures of the two chambers (7) and (11), the processing gas in the reaction chamber (11) can be processed gas in the heating chamber (7).
It will not flow to the side.

Further, a quartz window (1) in which quartz glass is fitted on the upper wall of the heating chamber (7) facing the object (3) to be heated (1)
9) is formed, and the above-mentioned lamp unit (2) is arranged so as to face the quartz window (19). The lamp unit (2) comprises a box-shaped lamp housing (20) and a lamp row (21) arranged in two stages in the lamp housing (20). Then, the inner wall of the lamp housing (20) is configured by a mirror-finished flat surface, and the surface of the inner wall is plated with gold.
Although not shown, the lamp housing (20) can be water-cooled in order to protect the gold plating from high temperatures during work.

Each lamp row (21) arranged in the lamp housing (20) is constituted by arranging a plurality of straight tube halogen lamps (22) in parallel, and the lamp row (21a) located in the upper stage. The straight row halogen lamps (22) are arranged so as to be orthogonal to the lamp row (21b) located in the lower row. Then, in each lamp row (21), as shown in FIG. 1, the lamp array density in the central portion is formed to be coarser than the lamp array density in other portions.

By arranging the heating lamps (22) in the lamp unit (2) in this way, the heating amount in the central portion of the object to be heated with a small amount of heat radiation is reduced and the temperature in the central portion is reduced. Can be prevented from becoming too high, and the peripheral side edge portion with a large amount of heat radiation can be heated more strongly than the central portion, and the temperature distribution in the object to be heated can be maintained uniform. Further, by forming the inner wall surface of the lamp housing (20) with a flat surface, the processing and plating work can be facilitated, and the reflectance of the lamp housing (20) can be increased to 98%.

FIG. 3 shows another embodiment of the invention, which is
The lamp housing (20) is formed in a hexagonal shape, and the lamp rows (21) are arranged in three stages inside the lamp housing (20).
The lamp rows (21a) and (21b) located above and below the lamp row (21c) arranged in the middle stage are arranged with their phases changed by 60 degrees in the opposite direction. Also in this case, each lamp row (21) The lamp array density in is configured such that the central portion becomes rough.

[0017]

According to the present invention, since the inner wall surface of the lamp unit is composed of a flat surface plated with gold, the production of the lamp housing and the gold plating work can be performed easily and with high accuracy, and the reflection efficiency of the lamp housing can be improved. Higher energy can be imparted to the object to be heated.

Further, a plurality of straight lamps arranged in parallel in the lamp unit are arranged in a plurality of rows, and the upper and lower lamp rows are positioned so that the straight lamps cross each other. The arrangement pitch of straight tube lamps in each lamp row is arranged so that the central part becomes coarse, so the temperature of the central part of the heated object becomes high without controlling the output of each lamp individually. It is possible to prevent overheating and uniformly heat the entire object to be heated.

[Brief description of drawings]

FIG. 1 is a bottom view of a lamp unit.

FIG. 2 is a sectional view of a chamber portion of a CVD apparatus.

FIG. 3 is a bottom view of a lamp unit of another embodiment.

FIG. 4 is a schematic diagram showing a conventional lamp arrangement.

[Explanation of symbols]

1 ... Decompression chamber, 2 ... Lamp unit, 3 ... Object to be heated, 19 ... Quartz window, 20 ... Lamp unit, 21 ... Lamp row, 22 ...
Straight tube lamp.

Claims (3)

[Claims] 1. An object to be heated (3) supported in the decompression chamber (1) is heated by radiating heat rays from a lamp unit (2), and a processing gas is supplied into the decompression chamber (1). In a CVD apparatus configured to form a thin film on the surface of the object to be heated (3), a decompression chamber
(1) and the lamp unit (2) are connected via a quartz window (19), the inner wall surface of the lamp unit (2) is constituted by a flat surface plated with gold, and a plurality of straight pipes are arranged in the lamp unit (20). The lamp row (21) configured by arranging the lamps (22) in parallel is arranged in a plurality of stages, and the lamp rows (21) positioned above and below are positioned so that the straight tube lamps (22) cross each other. A heater for a CVD apparatus, characterized in that the arrangement pitch of the straight tube lamps (22) in each lamp row (21) is arranged so that the central portion thereof is rough. 2. A straight tube lamp (22) having lamp rows (21) arranged in upper and lower two stages, which constitutes an upper lamp row (21a), and a straight tube lamp (22) constituting a lower lamp row (21b). The heater of the CVD apparatus according to claim 1, wherein the heater and the heater are arranged orthogonal to each other. 3. The lamp rows (21) are arranged in three rows above and below, and the lamp rows (21a) (21b) located above and below the lamp row (21c) located in the middle row are arranged at 60 degrees in opposite directions. The heater for a CVD apparatus according to claim 1, wherein the heaters are arranged with different phases.