JPH03109722A - Heat-treating apparatus for semiconductor - Google Patents

Abstract

PURPOSE:To accurately control the temperature of a wafer by inserting a paddle thermocouple vertically passing the wafer into a treating tube. CONSTITUTION:Branches 13 are respectively provided at upper, intermediate and lower positions of a boat 23 at a paddle thermocouple 9, a temperature detecting wafer 10 is placed on the end of the branch 13, detecting part 11a of the thermocouple 11 is attached to the lower surface of the wafer 10, and leads 4a are connected to a temperature controller 7. In this case, since the heating conditions become equal to those of a wafer 8 at the time of operation, heating temperature of the wafer 8 in the actual operation can accurately be obtained by gaining correlation between the temperature and the temperature of a heater 4 detected by a thermoelectric material 6. Thus, the heating temperature of the wafer 8 can accurately be controlled by the controller 7.

Description

[Detailed description of the invention] [Purpose of the invention] (Industrial application field) The present invention relates to a semiconductor heat treatment apparatus.

(Prior Art) In FIG. 5 showing a conventional semiconductor heat treatment apparatus, a coil-shaped heater 4 is provided on the inner wall of a cylindrical furnace body 20 made of a heat insulating material. A cylindrical processing tube 1 with a convex cross section is inserted from below, a lid 1a is attached to the lower end of the processing tube 1, and the inside of the processing tube 1 is moved up and down by a lifting mechanism (not shown). Boat 3 is stored.

On the other hand, in this boat 3, approximately 100 approximately disk-shaped wafers 2 are placed at predetermined intervals on a shelf (not shown) of the boat 3, and a processing tube 1 heated by a heater 4 and a processing tube 1 Approximately 10% of the processing gas is sent from a supply port (not shown)
Heat treated in an atmosphere of 00°C.

Further, the heater 4 includes a thermocouple 6 for detecting the temperature of the heater 4.
are provided at the top, middle, and bottom, and their lead wires 6a are connected to a separately placed temperature control device 7, and the heater 4 is also connected to the temperature control device 7 with an electric wire 14a to supply a predetermined power. .

In the semiconductor heat treatment apparatus configured as described above, before processing wafers that will become actual products, first, in order to suppress the soaking length inside the processing tube 1 within a predetermined range, as shown in FIG. The temperature inside the processing tube 1 is detected by inserting a paddle thermocouple 5 having a thermocouple 5a inserted into the thin tube from below the processing tube 1.

At the same time, this detection result is compared with the temperature of the heater 4 detected by the thermocouple 6 to determine the correlation between them.
From this result, the temperature control device 7 controls the power supplied to the heater 4 via the conductor 4a so that the distribution of the internal temperature of the processing tube 1 estimated from the temperature of the heater 4 becomes a predetermined value.
Conditions for obtaining a predetermined soaking length are required.

Based on the conditions thus obtained, the actual product wafer 2 is heat-treated while being controlled by a temperature control device.

(Problem to be Solved by the Invention) However, in such a semiconductor heat treatment apparatus, the temperature detected by the paddle thermocouple 5 is different from the temperature of the wafer 2, and the temperature of the wafer 2 is different from the temperature of the heater 4 and the temperature of the paddle thermocouple 5. Because it is estimated from the correlation with the detected temperature, wafer 2
temperature cannot be precisely controlled.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to obtain a semiconductor heat treatment apparatus that can detect the temperature of a wafer for setting conditions with high precision and can control the temperature with high precision.

[Structure of the invention]

(Means for Solving the Problems) In the present invention, a heater arranged in a cylindrical manner in a cylindrical furnace body and a cylindrical processing tube are coaxially inserted, and a boat is inserted into and removably into the processing tube. This is a semiconductor heat treatment apparatus in which wafers are placed concentrically in a boat, and a paddle thermocouple that vertically penetrates the wafers is inserted into the processing tube.

(Function) As a result, the detection portion of the paddle thermocouple is located at a position under exactly the same heating conditions as the heated wafer during actual operation.

(Embodiment) An embodiment of the semiconductor heat treatment apparatus of the present invention will be described below with reference to the drawings. However, parts that overlap with Fig. 5 are omitted.

In FIG. 1, between the right side of the boat 23 and the processing tube 1, a tubular paddle thermocouple 9 with a thermocouple inserted therein is installed so that the lower end of the lid 1a of the opening at the lower end of the processing tube 1 is inserted. This paddle thermocouple 9 is provided on the boat 23,
The middle and lower portions are provided with branch parts 13 bent to the left as shown in detail in FIG. 12 is provided, and a small-diameter disk-shaped wafer 10 for temperature detection is placed in the saucer 12. A detection part 11a of a thermocouple 11 is attached to the lower surface of this wafer 10, and this lead wire 4a is connected to the temperature control device 7.

On the other hand, the boat 23 has the same external shape as the actual product, and as shown in detail in FIG.
Test wafers 8 with holes ++m larger in diameter and grooves 8b with a width approximately 10 nn wider than the diameter of the branch 13 formed between the center of the reference surface 8c on the right side are placed at the same spacing as in actual operation. They are placed concentrically above and below on shelves (not shown).

Further, on the right side of the boat 23, grooves (not shown) having a width approximately 100111 times wider than the diameter of the branch portion 13 are formed in the upper and lower end plates, and in FIG.
It is located in the center of the groove between the boat 23 and the wafer 8 when viewed from above, and when the paddle thermocouple 11 is moved up and down by a drive device (not shown) provided below the lid 1a, the branch portion 13
is adapted to move without contacting the wafer 8 or the inner surface of the groove of the boat 23.

In FIG. 1, there is no wafer 8 on the boat 23 at the height of the wafer IO and the branch I3, but this is to show the position of the wafer 10 and the branch 13, and in reality, they are at the same interval above and below. It is listed in .

In the semiconductor heat treatment apparatus configured in this way, the heating conditions for the wafer lO before actual operation are the same as the wafer heating conditions during actual operation, so the difference between this temperature and the temperature of the heater 4 detected by the thermocouple 6 is By determining the correlation, the heating temperature of the wafer in actual operation can be determined accurately, so that the temperature control device 7 can control the heating temperature of the wafer with high precision.

Moreover, since the paddle thermocouple 9 can be moved up and down, the soaking length can also be measured.

FIG. 4 shows another flow side of the semiconductor heat treatment apparatus of the present invention, and the center of the boat 17 has vertical end plates that penetrate through the upper and lower end plates of the boat 17 and the center hole of the mounted wafer. The same paddle thermocouple 5 as shown in FIG. 5 is inserted, and detection parts are provided inside the paddle thermocouple 5 at the heights located above, in the middle, and at the bottom of the boat 17, as in FIG. The lines are each connected to a temperature control device 7.

In this case, the conventional paddle thermocouple 5 shown in FIG. 5 can be used as is, and the wafer has a groove 8b shown in FIG.
Since it is not necessary to form, there is an advantage that the yield rate increases.

〔Effect of the invention〕

According to the present invention, a heater arranged in a cylindrical manner in a cylindrical furnace body and a cylindrical processing tube are coaxially inserted, and a boat is removably inserted into the processing tube. In semiconductor heat treatment equipment where wafers are placed concentrically on a boat, by inserting paddle thermocouples that penetrate the wafers vertically into the processing tube, the wafers can be heated under the same conditions as during actual operation. Since the degree of ripeness of the wafer is detected, it is possible to obtain a semiconductor heat treatment apparatus that can control the heating temperature of the wafer with high precision.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view showing one embodiment of the semiconductor heat treatment apparatus of the present invention, FIGS. 2 and 3 are partial detailed views of FIG. 1, and FIG. 4 is another embodiment of the semiconductor heat treatment apparatus of the present invention. FIG. 5 is a longitudinal sectional view showing an example of a conventional semiconductor heat treatment apparatus. 1... Processing tube 4... Heater 8...
Wafer 9... Paddle thermocouple 20...
Furnace body 23...Boat (8733)

Claims (1)

[Claims] A cylindrical heater arranged in a cylindrical shape and a cylindrical processing tube are coaxially inserted into the cylindrical furnace body, a boat is removably inserted into the processing tube, and wafers are inserted into the boat. What is claimed is: 1. A semiconductor heat treatment apparatus arranged concentrically, wherein a paddle thermocouple that vertically penetrates the wafer is inserted into the processing tube.