JPH0239425A - Apparatus for manufacturing semiconductor - Google Patents

Abstract

PURPOSE:To reduce the contamination of a core tube in which wafers are treated caused by a heater part and make the temperature of a furnace main part closer to be inner temperature of the core tube by a method wherein the core tube is composed of a double-tube structure and thermocouples are provided in the outer core tube and the outer core tube is purged with nitrogen gas. CONSTITUTION:A core tube 3a is a double-layer core tube and the atmosphere of its outer part is replaced with nitrogen gas supplied by a nitrogen gas introducing tube 4a. Built-in thermocouples 6a are used as thermocouples for temperature control. The built-in thermocouple 6a is built in a quartz glass tube and hardly influenced by the external atmosphere. The core tube 3a is put on the inner wall of a uniformly heating tube 2 and heat insulators are provided between the heating tube 2 and a heater part 1 to fix the core tube 3a to the heater part 1.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a semiconductor manufacturing apparatus for processing wafers in a furnace core tube of a heat treatment furnace such as a diffusion furnace, a low pressure CVD furnace, or a plasma CVD furnace.

[Conventional technology]

Semiconductor manufacturing equipment that performs heat treatment using a conventional furnace core tube is
As shown in FIG. 3, thermocouples 6c are attached to each heater part 1, and the furnace core tube 3C is inserted into each thermocouple, and the gap between the heater part 1 and the furnace core tube 3C is sealed and fixed with a heat insulating material 7. There are, but
If the insulation material 3C is inserted incorrectly, the thermocouple 6C will be affected by the external atmosphere, causing temperature instability, or
Even in cases where this is not the case, there is a temperature difference between the actual furnace body temperature and the furnace core tube internal temperature, which is unfavorable in terms of the process, and the more the furnace core tube 3c becomes dirty, the larger the temperature difference becomes.

In addition, the thermocouple 6C used for temperature control is weak against reducing atmospheres and has a short lifespan in heat treatment furnaces that use hydrogen, requiring replacement after about a year. In some cases, the furnace core tube 3c was contaminated by outgas from the heater part 1.

[Problem to be solved by the invention]

Contamination of the furnace core tube by outgas from the heater has been a problem in the above-mentioned part of the heater and the furnace core tube. Furthermore, with conventional methods of temperature control, there was a problem with the difference between the controlled temperature of the furnace body and the actual temperature inside the furnace core tube.

[Differences between the invention and the prior art]

Compared to the above-mentioned temperature control system for semiconductor manufacturing equipment that uses a conventional furnace core tube to perform heat treatment, the present invention has a structure in which the furnace core tube is doubled, a thermocouple is built into it, and nitrogen The difference is that replacement is performed with gas.

[Means to solve the problem]

The structure of the present invention is a semiconductor manufacturing apparatus that uses a furnace core tube and performs heat treatment in a part of the heater, in which the furnace core tube 2 has a double structure, a thermocouple is inserted into the outer furnace core tube part, and a contamination prevention measure is taken. It is characterized by flowing nitrogen gas through the furnace core tube, and its temperature control is characterized by stabilizing the temperature closer to the furnace core tube.

〔Example〕

FIG. 1 is a sectional view of a semiconductor device manufacturing apparatus according to an embodiment of the present invention. In the same figure, in this manufacturing apparatus, the furnace core tube 3a of the present invention is a double furnace core tube, and the outer part is in a state where nitrogen gas is substituted by a nitrogen gas introduction tube 4a, and the furnace core tube 3a of the present invention is replaced with nitrogen gas, which is used for temperature control. The thermocouple is a built-in thermocouple 6a
controlled by. Since the built-in thermocouple 6a is also built into the quartz glass tube, the structure is not easily affected by the external atmosphere. The furnace core tube 3a of the present invention is fixed by placing the furnace core tube 3 & on top of the soaking tube 2 with respect to the heater part 1 and filling the heat insulating material 7 with it.

FIG. 2 is a sectional view of a semiconductor manufacturing apparatus according to another embodiment of the present invention. The furnace core tube 4b is fixed by a heater part 1 and a heat insulating material 7, and is composed of a front hatch plate 9 and an evacuation pipe 8 in order to create a vacuum inside the furnace core tube. The temperature control is stabilized by the built-in thermocouple 6b, and there is an advantage that nitrogen gas can be introduced and replaced through the nitrogen gas introduction pipe 4b to prevent contamination of the furnace core tube.

〔Effect of the invention〕

As explained above, the present invention can reduce contamination of the furnace core tube from a part of the heater in semiconductor manufacturing equipment that performs heat treatment using a furnace core tube, and can also control the temperature of the furnace body. It has the effect of bringing it closer to

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing a semiconductor device manufacturing apparatus according to a first embodiment of the present invention, FIG. 2 is a cross-sectional view showing a semiconductor device manufacturing apparatus according to a second embodiment of the present invention, and FIG. It is a sectional view showing a conventional example. 1... Part of the heater, 2... Soaking tube, 3
a...Furnace core tube, 3b...Furnace core tube, 3C
...Conventional furnace core tube, 4a...Nitrogen gas introduction pipe, 4b...Nitrogen gas introduction pipe, 5...
・Process gas introduction pipe, 6a...Thermocouple, 6b
...Thermocouple, 6C...Thermocouple, 7...
... Heater part insulation material, 8 ... Vacuum exhaust pipe. Agent: Susumu Uchihara / θ Fronthatsushi, Patent Attorney

Claims (1)

[Claims] In semiconductor manufacturing equipment that uses a furnace core tube and performs heat treatment,
Semiconductor manufacturing equipment characterized by having a double structure furnace core tube for processing wafers, a temperature control thermocouple inserted into the outer furnace core tube, and purging with nitrogen gas.