JPH043495Y2 - - Google Patents

Description

[Detailed explanation of the invention] A. Industrial application field This invention is used for annealing semiconductor wafers.
It relates to an infrared heating device used for processing, etc.

(b) Prior art In addition to annealing after ion implantation and polysilicon layer formation, the purpose of the annealing process for semiconductor wafers is to reduce the resistance of the polysilicon layer, recrystallize it,
Sintering and alloying of aluminum, nickel, chromium, etc. on the front and back surfaces of a semiconductor wafer are performed, and an electric furnace is generally used as a heating means in such an annealing process. However, as recent semiconductor technology has become more dense and precise due to VLSI devices, electric furnace annealing has begun to reach its limits in terms of electrical activation of impurities in high-concentration impurity regions within semiconductor wafers. The development of annealing technology is awaited as these semiconductor technologies progress.

New annealing techniques such as laser annealing, electron beam annealing, and infrared annealing have been reported in the literature, and among these, methods that are more suitable for uniformly and simultaneously heating large areas such as semiconductor wafers have entered the practical stage. There is an infrared annealing method that uses an infrared lamp as a heating source. An infrared heating device for annealing semiconductor wafers using this infrared annealing method has, for example, infrared lamps and their reflectors placed in the upper and lower parts of one heating chamber, facing each other vertically, and the semiconductor wafer is positioned and carried between the upper and lower infrared lamps. A device is used that heats the front and back surfaces of a semiconductor wafer to high temperatures (500°C to 1500°C) for a short period of time by turning on upper and lower infrared lamps simultaneously or sequentially.

This type of infrared heating device has an opening in one side wall of a heating chamber that houses an infrared lamp and a reflector, through which objects to be heated such as semiconductor wafers can be taken in and out, and this opening is appropriately closed with a lid. Since the inside of the machine becomes hot, it is practical to install air cooling or water cooling means on both sides of the machine to prevent abnormal rises in the internal temperature and to control the temperature by keeping the internal temperature constant at the start of heating work. has been made into By the way, the lid that constitutes a part of the heating chamber is a movable structure that is manually or automatically attached to and removed from the heating chamber, and therefore, it is not currently equipped with forced cooling means. For this reason, in equipment for annealing semiconductor wafers, the lid itself is often heated to high temperatures, which can be dangerous to handle, and the heat from the lid causes the temperature inside the furnace to rise irregularly, making it difficult to control the temperature inside the furnace. I was making it difficult.

C. Purpose of the invention The present invention was created in view of the above-mentioned problems, and aims to provide an infrared heating device that prevents abnormal temperature rises in the lid of a heating furnace, is safe to handle, and is easy to control the temperature inside the furnace. purpose.

D. Structure of the invention The present invention is attached to an opening for entering and exiting objects to be heated provided in one side wall of a heating furnace that houses an infrared lamp, so that the opening can be slid open and closed to appropriately close the opening, and the device is capable of holding objects to be heated. It is characterized in that a cooling means is attached to the lid body, which integrally projects from the inner surface of the support arm that is carried into the heating furnace.

E. Example An example in which the present invention is applied to an infrared heating device for annealing semiconductor wafers will be described with reference to the drawings.
1 to 3, 1 is a semiconductor wafer as an object to be heated, 2 is a heating furnace, 3 is an opening for entering and exiting the semiconductor wafer formed in the front wall of the heating furnace 2, and 4
is a lid body that closes the opening 3 as appropriate. The heating furnace 2 has, for example, a two-part structure, and includes a furnace body 5 having a U-shaped cross section and a U-shaped cover 6 that is fitted and fixed around the opening of the furnace body 5 . In the furnace body 5, 7a is an upper heating part, 7b is a lower heating part, 8, 8... are air-cooled nozzles whose upper and lower sides are arranged on the sides of each heating part 7a, 7b, 9, 9 are each heating part 7a, A light shielding plate 10 for preventing infrared rays from leaking to the outside from the sides of 7b is a rectangular quartz tube with an open end and a bottom, which is inserted between the upper and lower opposed heating parts 7a and 7b. It faces the opening 3 formed in the front plate 5a of the furnace body 5. The cover 6 is fixed to the furnace body 5 by means such as screws, and on both side plates 6a, 6b, a plurality of exhaust fans 11, 11, . is installed.

The upper heating section 7a has a plurality of furnaces, for example, four linear infrared lamps 12, 12 arranged in parallel, and bucket-shaped reflecting mirrors 13, 13, each having a parabolic cross section and placing each of these lamps at a focal position, on the lower surface. The reflective block 14a is comprised of a reflective block 14a, and a cooling pipe 17 that cools the reflective block 14a by passing cooling water 16 through a water cooling hole 15 formed in a meandering shape in the reflective block 14a. The lower heating section 7b includes five linear infrared lamps 12, 12, .
A reflective block 14b having 13... on its upper surface;
It consists of a cooling pipe 17' that cools the reflection block 14b with water. The infrared lamps 12, 12, . Heating temperature can be determined. The infrared lamps 12, 12, . . . of the upper and lower heating sections 7a, 7b and the paired reflecting mirrors 13, 13, . . . are arranged to uniformly heat the front and back surfaces of the semiconductor wafer 1.

The lid body 4 is fixed perpendicularly to the front ends of two parallel guide rods 18, 18 that extend slidably from the bottom of the furnace body 5 toward the front of the furnace.
By sliding the lid body 4 along the axial direction of the lid body 8
faces the opening 3 so as to be openable and closable. A support block 19 is fixed to the inner surface of the lid body 4, and two parallel support arms 20, 20 made of quartz are provided inwardly protruding from the support block 19.
The semiconductor wafer 1 is positioned and placed on the tip portions of the wafers 0 and 20. The support block 19 is the support arm 2
0 and 20 are both of a size that can be carried into the quartz tube 10 in the furnace, and on the tip of each support arm 20, 20 there are support protrusions 21, 21, . . . , which support the semiconductor wafer 1 at four points. Guide protrusions 22, 22, . . . for positioning at points are formed. Furnace opening 3 of lid body 4
The opening and closing operations are performed automatically when the semiconductor wafers 1 are supplied and taken out, but the drawing shows an example in which the opening and closing operations are performed manually by attaching a handle 23 to the front surface of the lid body 4.

Now, the feature of this embodiment is that the following water-cooled cooling means 24 is attached to the lid body 4. This water-cooled cooling means 24 is connected to the support block 19 from the outside with water-cooled pipes 2.
5 and 25, the lid body 4 is forcibly cooled mainly by the support block 19. water cooling pipe 2
Flexible pipes are used for the external lead-out portions 5 and 25, thereby making the opening/closing operation of the lid body 4 smooth. One of the water cooling pipes 25, 25 is a water supply pipe that sends cooling water 26 to the support block 19, and the other is a drain pipe.

Next, the operation of the heating device will be explained. First, the lid 4 is sufficiently separated from the heating furnace 2 and the support arm 2 is
A semiconductor wafer 1 is supplied on top of the wafers 0 and 20. Next, the lid 4 is pushed in until it closes the opening 3 of the furnace, and the semiconductor wafer 1 is placed inside the quartz tube 10 as shown in FIG.
The support block 19 is inserted into the open end of the quartz tube 10. Before and after this, a desired atmospheric gas is blown into the quartz tube 10.
This gas blowing may be carried out, for example, by connecting the gas supply pipe 27 to the closed end 10' of the quartz tube 10. Then, the infrared lamps 12, 12, . . . are turned on to heat the semiconductor wafer 1 to start annealing.
In addition to water cooling of the infrared lamps 12, 12, . . . by the air cooling nozzles 8, 8, . When the annealing is completed, the air cooling and water cooling are selectively continued or stopped, the lid 4 is opened, the semiconductor wafer 1 is taken out, and a new one is supplied. Thereafter, similar operations are repeated.

Note that the present invention is not limited to the above-described embodiment; for example, the water cooling structure of the lid body 4 may be such that the guide rods 18, 18 are shaped like pipes and the cooling water is sent from there to the support block 19. The water cooling pipe can be omitted from the front surface of the lid body 4. Furthermore, the invention is not limited to a heating device for annealing semiconductor wafers, and the heating furnace and its lid can be modified as appropriate depending on the object to be heated.

F. Effects of the invention As described above, according to the invention, the danger associated with the abnormal temperature rise of the lid, which often occurs in infrared heating devices, is significantly reduced, making handling safer, and making it easier to control the temperature inside the heating furnace. In addition, high-speed control is possible, and the life of the lamp can be extended.

[Brief explanation of drawings]

Fig. 1 is a partially omitted perspective view showing an embodiment of the present invention, Fig. 2 is a cross-sectional view taken along line A-A in Fig. 1, and Fig. 3 is a cross-sectional view taken along line B-B in Fig. 2. , FIG. 4 is a sectional view of the cover shown in FIG. 2 during operation, and FIG. 5 is a perspective view of the cover shown in FIG. 1. 1... object to be heated, 2... heating furnace, 3... opening,
4...Lid body, 18...Support arm, 24...Water cooling type cooling means.

Claims (1)

[Scope of utility model registration request] The lid is slidably attached to the opening for entering and exiting the heated object formed on one side wall of the heating furnace that houses the infrared lamp, and has a support arm integrally protruding from the inner surface to hold the heated object. An infrared heating device characterized by being equipped with a means.