JPH02187015A - Heating device - Google Patents

Abstract

PURPOSE:To simultaneously heat a plurality of workpieces without overbaking the workpiece by heating the workpiece in a state when inert gas flows, and cooling the workpiece with clean air flowing therearound after separating the workpiece from a plate heater. CONSTITUTION:A semiconductor substrate 51 is carried in on a placing pin 5 from a substrate delivery port 33. Then, a plate heater 1 is lifted by a lifting device to place the substrate 51 on the heater 1. Simultaneously, a heat insulation member 2 is brought into contact with the lower end surface of a heat insulation chamber 25 to construct a processing chamber. The heater 1 is kept at 200 deg.C to keep the substrate 51. Inert gas is blown into in heating, and excessive gas and outgas are discharged from a heat insulating cover 19. Clean air from a clean air supply device 35 is forced to flow from a vent 29 into a cover 27 in the heating, and discharged through vents 31, 15, 9. After the heating the heater 1 is lowered to place the substrate 51 on the placing pin 5, and the clean air from the device 35 is forrced to flow from the delivery port 33 and is discharged from an exhaust duct 7 to cool the substrate 51.

Description

[Detailed description of the invention] [Purpose of the invention] (Industrial application field) The present invention relates to a heating device.

(Prior Art) There are the following heating devices, for example, heating devices used in a heat treatment process in semiconductor manufacturing.

That is, a lower housing having a plate heater on which a semiconductor substrate is placed is brought into contact with an upper housing to form a processing chamber, and the semiconductor substrate is heat-treated.

(Problem to be Solved by the Invention) However, in the heating device as described above, the temperature of the plate heater remains the same, and since the semiconductor U board is placed on the plate heater, the semiconductor substrate remains under the heating condition due to radiant heat, resulting in overbaking. (heating for a predetermined time or more). Therefore, after the heat treatment, the semiconductor substrate had to be immediately removed from the heating apparatus to prevent the semiconductor substrate from being overbaked.

In addition, the heat from the plate heater raises the temperature to the surrounding lower housing, so if other similar heat treatment chambers are placed side by side, heat conduction between the two heat treatment chambers will prevent heat treatment at an appropriate temperature. There were other problems.

The present invention was made to solve such problems,
The purpose of this is to prevent overbaking of objects to be processed even if unprocessed objects, such as semiconductor substrates, remain in the heating device after heat treatment, and to avoid overbaking of objects to be processed, such as semiconductor substrates, by placing multiple processing chambers side by side. An object of the present invention is to provide a heating device capable of heat-treating an object to be treated.

[Structure of the Invention] (Means for Solving the Problems) In order to achieve the above object, the present invention provides a plate heater that heats an object to be processed while an inert gas is flowing to an exhaust port;
A holding means for holding the object to be processed by moving the plate heater and the object to be processed relative to each other after a predetermined heating period by the plate heater, and a state in which the object to be processed is held by the holding means. The apparatus is characterized by comprising a cooling means for circulating clean air to cool the object to be processed.

(Function) In the present invention, during the heat treatment, the object to be treated is heated by the plate heater in a state where an inert gas is flowing to the exhaust port. After the predetermined heating period, the holding means
The plate heater and the object to be processed are relatively moved and separated, and the object to be processed is held. and,
Since the object to be processed is cooled by circulating clean air by the cooling means in this held state, the object to be processed is not overbaked by the radiant heat of the plate heater.

(Embodiment) An embodiment in which the apparatus of the present invention is applied to a baking apparatus for baking substrates such as semiconductor wafers will be described in detail below with reference to the drawings.

This baking device is constructed as follows.

A plate heater 1 whose surface is treated with hard alumite, for example, is horizontally connected to a lifting device (not shown), and a heat insulating member 2 is provided around the upper surface of the plate heater 1. A bottom plate 3 provided on the device body below the plate heater 1
A holding means, for example, a set of three mounting bins 5 that can penetrate the plate heater 1 in the vertical direction is erected so as to form a supporting surface. A rectangular pipe-shaped exhaust duct 7 is provided around the bottom plate 3 and is connected to an exhaust device 6 and has a damper (not shown) for adjusting the displacement.

A lower ventilation port 9 is provided on the inner surface of the exhaust duct 7.

A vent 11 is provided on the upper surface of the exhaust duct 7 on the side opposite to a wafer entrance/exit, which will be described later, and a rectifying guide plate 12 for promoting gas flow into the vent 11 is provided above the vent 11 .

A shutter member 13 is connected to the heat insulating member 2 so as to be vertically slidable on the inner surface of the exhaust duct 7 and capable of shielding the lower vent 9 .

A vent hole 15 is provided on the upper surface of the shutter member 13.

Above the plate heater 1, a heat insulating cover 19 having a ventilation hole 17 on the lower surface is fixedly installed on the main body of the apparatus (not shown). The heat insulating cover 19 is connected to an exhaust device 21 . The lower surface of the heat insulating cover 19 has a cylindrical heat insulating chamber 25 which has a vent 23 overlapping the vent 17 and can come into contact with the heat insulating member 2.
is provided facing the plate heater 1.

The heat insulating cover 19 and the heat insulating chamber 25 are connected to the main body of the device (
(not shown) by a housing-like cover 27 fixed to the
The heat insulating chamber 25 is fitted and surrounded by the lower surface of the cover 27 . A vent hole 29 is provided on the top surface of the cover 27. The lower surface of the cover 27 can come into contact with the upper surface of the shutter member 13 and has a vent 31 that overlaps the vent 15. When the lower surface of the cover 27 and the upper surface of the shutter member 13 are separated, a substrate entrance/exit 33 is formed for loading and unloading semiconductor substrates in a predetermined direction (left side in the figure). Clean air supplied from a cooling means, for example, a clean air supply device 35, can selectively flow into the vent hole 29 and the substrate inlet/outlet port 33.

Next, the operation of this heating device will be explained.

First, the semiconductor substrate 5 is transferred by a transfer robot (not shown).
1 is carried onto the mounting pin 5 through the substrate entrance/exit 33 (FIG. 1). Subsequently, the plate heater 1 is raised by a lifting device (not shown), and the semiconductor substrate 51 is placed 1'F'TIL on the plate heater 1 (FIG. 2). Note that adhesion of dust to the semiconductor substrate 51 can be avoided by slightly separating the semiconductor substrate 51 from the surface of the heater 51 as necessary. At the same time, the heat insulating member 2 is brought into contact with the lower end surface of the heat insulating chamber 25, thereby forming a processing chamber. Note that the plate heater 1 is maintained in advance at a predetermined temperature, for example, 200° C., by a heating control device (not shown).

Thereafter, the semiconductor substrate 51 is heated while being placed on the plate heater 1 for a predetermined period of time. During the heat treatment, an inert gas (not shown), such as nitrogen gas, is blown into the processing chamber from a nitrogen gas supply device, so that the semiconductor substrate is placed in an inert gas atmosphere, and resists, etc. on the semiconductor substrate are exposed to the atmosphere during the heat treatment. Outgas and excess nitrogen gas generated from the heat insulating cover 19 are discharged from the heat insulating cover 19.

During the above heat treatment, clean air supplied from the clean air supply device 35 flows into the cover 27 from the vent 29. The inflowed clean air is passed through the vent 31
．． 15 and further passes through the lower ventilation port 9 and is discharged from the exhaust duct 7 to the outside. Since the area around the processing chamber is air-cooled by this circulation of clean air, the area around the processing chamber, such as the bottom plate 3 and the cover 27, will not be heated to a high temperature, e.g., 50° C. or higher, due to the heat from the plate heater 1.

Next, after the heat treatment, the plate heater 1 is lowered by a lifting device (not shown), and the semiconductor substrate 51 is placed on the mounting bin 5. At this time, the heat insulating member 2 is isolated from the lower end surface of the heat insulating chamber 25, and a substrate entrance/exit 33 is formed. At the same time, the shutter member 13 is also lowered, so that the lower vent 9 is covered, while the vent 11 is opened to the outside.

The clean air supplied from the clean air supply device 35 flows in from the substrate inlet/outlet 33 and passes through the atmosphere of the semiconductor substrate 51 held in the mounting bin 5 to the vent hole 11.
and is discharged from the exhaust duct 7 to the outside. Therefore, after the heat treatment, the semiconductor substrate 51 is quickly air-cooled by the circulation of clean air (by the way, the semiconductor substrate 51
One minute after heat-treating 1 to 200°C, the semiconductor substrate 5
It was possible to cool the temperature down to 30°C. ), a faster cooling effect than atmospheric air cooling was observed, and it was demonstrated that there was no overbaking due to the radiant heat of the plate heater 1.

As described in detail above, according to this embodiment, even if an unprocessed object such as a semiconductor substrate remains in the heating apparatus after the heat treatment, the object to be processed will not be overbaked.

In addition, during heat processing, the area around the processing chamber is air-cooled by the airflow of clean air supplied from the clean air supply device, and the area around the processing chamber does not become high temperature due to the heat from the plate heater, so the same heating Even if a plurality of processing chambers are arranged side by side (not shown), there is no influence of heat conduction between the heat processing chambers, and heat treatment can be performed in any of the processing chambers at an appropriate temperature. That is, it is possible to provide a heating device that can heat-process a plurality of objects to be processed at the same time by arranging a plurality of processing chambers side by side.

In the above embodiment, an example in which the present invention is applied to a baking apparatus for baking a semiconductor substrate or the like has been described, but the present invention can be applied to any apparatus that heats an object to be processed.

[Effects of the Invention] As explained in detail above, according to the present invention, even if an unprocessed object such as a semiconductor substrate remains in the heating device after heat treatment, the object to be processed will not be overbaked, and ,
It is possible to provide a heating device that can heat-process a plurality of objects to be processed at the same time by arranging a plurality of processing chambers in parallel.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the state of the main part of the baking device according to the embodiment of the present invention before and after heat treatment, and FIG. 2 is a diagram showing the state of the main part of the baking device shown in FIG. 1 during heat treatment. be. 1...Plate heater 2...Insulating member 5...Placement bin 6...Exhaust device 7・・・・・・・・・Insulation cover 9・・・・・・Lower vent 11. 29. 5. 1......Vent 3...Shutter part 5...Clean air supply device 1...
・・・・・・Semiconductor substrate

Claims (1)

[Scope of Claims] A plate heater that heats an object to be processed while an inert gas is flowing to an exhaust port; and after a predetermined heating period by the plate heater, the plate heater and the object to be processed are relative to each other. A heating device comprising a holding means for moving and holding the object to be processed at a distance, and a cooling means for circulating clean air to cool the object while the object is held by the holding means.