JP2002093733A - Heat treatment apparatus for semiconductor wafer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat treatment apparatus of a semiconductor wafer, which can prevent air for cooling introduced into a space between a heater and a liner tube from leaking into load chamber. SOLUTION: A clearance between a tube support 5 and a flange 2c of a process tube 2 is sealed by an annular seal packing 16.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor wafer heat treatment apparatus used for forming an oxide film on a surface of a semiconductor wafer or performing processing such as diffusion.

[0002]

2. Description of the Related Art When forming a silicon oxide film (SiO ₂ ) on the surface of a semiconductor wafer, for example, a vertical heat treatment apparatus shown in FIG. 3 is used. This heat treatment apparatus includes a liner tube 101 having at least a lower end opened.
Is provided with a process tube 102 having an open lower end, and a heater 103 is disposed outside the outer periphery of the liner tube 101.

[0003] The lower end of the liner tube 101 is
It is held by an annular liner support 105. A flange 106 is provided at a lower portion of the outer periphery of the process tube 102.
A tube support 107 is interposed between the upper surface of the tube support 06 and the liner support 105.
07 and the skirt 108 sandwich the flange 106.

[0004] The tube support 107 is a frame 1
The liner support 105 is supported by the heater base 110 via the tube support 107. In the heat treatment apparatus, a semiconductor wafer which has been heat-treated and cooled to a predetermined temperature is placed in a process tube 10.
2 is provided with an elevating device 113 for carrying out from the interior of the apparatus 2 to the load chamber 112.

[0005]

In the above-described conventional heat treatment apparatus, air is supplied to the space A between the heater 103 and the liner tube 101 in order to shorten the cooling time after the completion of the heat treatment of the semiconductor wafer. May be introduced. However, in the conventional heat treatment apparatus, the sealing performance against the air introduced into the space A is not sufficiently considered, so that the air introduced into the space A is applied to the upper surface of the flange 106 and the tube support 10.
7 may leak to the load chamber 112, and if the air contains particles, the semiconductor wafer in the load chamber 112 may be contaminated with the particles. The present invention has been made in view of the above problems, and provides a semiconductor wafer heat treatment apparatus capable of preventing air introduced into a space between a heater and a liner tube from leaking into a load chamber. The purpose is to:

[0006]

A semiconductor wafer heat treatment apparatus according to the present invention for achieving the above object has a liner tube having an open lower end, a liner tube disposed inside the liner tube and having an open lower end. A process tube having a flange at the lower part of the outer periphery, a heater disposed outside the outer periphery of the liner tube, an annular liner support for holding a lower end of the liner tube, an upper surface of the flange of the process tube and the liner support; In a semiconductor wafer heat treatment apparatus including a tube support interposed between the tube support and a skirt that sandwiches the flange between the tube support and the tube support, a gap between the tube support and the flange is sealed with a seal packing. (Chart 1). According to the semiconductor wafer heat treatment apparatus having such a configuration, air introduced into the space between the liner tube and the heater in order to promote cooling of the semiconductor wafer after the heat treatment is applied to the gap between the tube support and the flange. Leakage to the load chamber through the seal packing can be prevented.

Preferably, in the semiconductor wafer heat treatment apparatus, a seal ring is provided along an outer periphery of the flange, and the seal packing is held between the seal ring, the outer periphery of the flange, and a tube support. . According to this heat treatment apparatus, since the seal packing can be securely held at three points: the seal ring, the outer periphery of the flange, and the tube support, the gap between the tube support and the flange can be reliably maintained for a long period of time. Can be sealed.

[0008]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a schematic cross-sectional view of a semiconductor wafer heat treatment apparatus according to an embodiment of the present invention, and FIG. 2 is an enlarged cross-sectional view showing a main part of the apparatus. In the heat treatment apparatus, a process tube 2 having an open lower end is arranged concentrically with a predetermined gap provided inside a liner tube 1 having an open upper end and a lower end, and a heater 3 is arranged outside the outer periphery of the liner tube 1. ing. The liner tube 1 is for uniformly transmitting radiant heat from the heater 3 to the process tube 2, and the lower end thereof is placed and held on an annular liner support 4. A predetermined space K is provided between the liner tube 1 and the heater 3.

The process tube 2 has a flange 2c protruding from a lower portion of the outer periphery thereof, and the flange 2c is sandwiched between the tube support 5 and the skirt 6 via a cushion material 2d along the upper and lower surfaces thereof. Thereby, it is supported in a floating state at a predetermined position. The cushion material 2d is made of polytetrafluoroethylene (P
It is formed of a flexible material such as TFE) or an aluminum plate or a material having a relatively low hardness.

The tube support 5 is mounted on a heater base 8 supported on a frame 7, and the liner support 4 is supported on the heater base 8 via the tube support 5. The tube support 5 and the heater base 8 are formed of an annular body having a hollow structure, in which cooling water is circulated and supplied. In addition,
O between the tube support 5 and the heater base 8
Sealed by ring X. The heater 3 is covered with a heat insulating wall 3a, and the heat insulating wall 3a is supported by the heater base 8. The skirt 6 is formed of an annular body having a hollow structure, and cooling water is circulated and supplied inside the skirt. The skirt 6 is attached to the tube support 5 by a bolt 6a suspended from the tube support 5 and a nut 6b screwed into the bolt 6a.

A quartz tube 9a is provided upright in the space between the liner tube 1 and the process tube 2, and a sensor 9 for measuring the temperature in the tube is introduced into the quartz tube 9a. . The sensor 9 passes through the opening 3b below the heater 3 and passes through the liner tube 1
It is introduced into a space between the liner tube 1 and the process tube 2 via a space K between the heater and the heater 3. The opening 3b is closed by a seal (not shown). Further, the heat treatment apparatus is provided with an air supply unit 12 for supplying air to a space K between the liner tube 1 and the heater 3. The air supply unit 12 supplies air to the space K after the heat treatment of the semiconductor wafer W is completed, thereby promoting cooling of the semiconductor wafer W.

Further, in the heat treatment apparatus, the semiconductor wafer W is loaded into the process tube 2 from the load chamber 14 below the process tube 2, or the semiconductor wafer W which has been subjected to the heat treatment and cooled to a predetermined temperature, An elevating device 13 for carrying out the process tube 2 to the load chamber 14 is provided. This lifting device 13
Is a wafer boat 13a for holding a semiconductor wafer W
It has.

In the heat treatment apparatus having the above structure, the tube support 5 and the flange 2c of the process tube 2 are provided.
Is sealed by an annular seal packing 16. The seal packing 16 is made of, for example, an O-ring, and is sandwiched by the seal ring 17 provided along the outer periphery of the flange 2c, the outer peripheral surface of the flange 2c, and the tube support 5 in an elastically contracted state. . Further, the seal ring 17 is supported by the skirt 6.

As described above, the gap between the tube support 5 and the flange 2c is sealed by the seal packing 16, so that the air is supplied from the air supply unit 12 to the space K between the liner tube 1 and the heater 3. The leaked air can be prevented from leaking into the load chamber 14 through the gap between the tube support 5 and the flange 2c. Therefore, even if the air contains particles, it is possible to prevent the semiconductor wafer in the load chamber 14 from being contaminated by the particles. In addition, since the seal packing 16 is held at three points: the seal ring 17, the outer periphery of the flange 2c, and the tube support 5, deterioration of the seal packing 16 due to heat is prevented, and the seal packing 16 is securely held. Thus, it is possible to effectively prevent air from leaking into the load chamber 14 from between the tube support 5 and the flange 2c over a long period of time. The seal packing 16 is provided on the flange 2c of the process tube 2.
May be interposed between the upper surface of the tube support 5 and the tube support 5.

[0015]

As described above, according to the heat treatment apparatus for a semiconductor wafer according to the first aspect, the gap between the tube support and the flange is sealed by the seal packing, and the space between the liner tube and the heater is sealed. Since the air introduced into the space is prevented from leaking into the load chamber through the gap, even if the air contains particles, the semiconductor wafer in the load chamber may be contaminated with the particles. Can be prevented.

According to the semiconductor wafer heat treatment apparatus of the present invention, since the seal packing is held at the three points of the seal ring, the outer periphery of the flange and the tube support, air is supplied from between the tube support and the flange. Can be effectively prevented from leaking into the load chamber for a long period of time, and the semiconductor wafer in the load chamber can be more reliably prevented from being contaminated with particles.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view showing a semiconductor wafer heat treatment apparatus according to an embodiment of the present invention.

FIG. 2 is an enlarged sectional view of a main part of FIG.

FIG. 3 is a schematic cross-sectional view showing a conventional semiconductor wafer heat treatment apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Liner tube 2 Process tube 2c Flange 3 Heater 4 Liner support 5 Tube support 6 Skirt 12 Air supply part 16 Seal packing 17 Seal ring

Continued on the front page F term (reference) 4K061 AA01 BA11 CA21 DA05 FA07 HA09 4K063 AA05 AA12 AA15 BA12 CA03 DA22 5F045 AA20 AB32 BB15 EB10 EC02 EK06 EK24 GB05

Claims (2)

[Claims] 1. A liner tube having an open lower end, a process tube disposed inside the liner tube, having an open lower end and having a flange at the lower part of the outer periphery, and a heater arranged outside the outer periphery of the liner tube. An annular liner support for holding a lower end of the liner tube, a tube support interposed between the upper surface of the flange of the process tube and the liner support, and clamping the flange between the tube support and the liner support. A heat treatment apparatus for a semiconductor wafer comprising a skirt, wherein a gap between the tube support and the flange is sealed by a seal packing. 2. The semiconductor wafer heat treatment apparatus according to claim 1, wherein a seal ring is provided along an outer periphery of said flange, and said seal packing is held between said seal ring, an outer periphery of said flange and a tube support.