JPH0529443A - Apparatus and method for cooling wafer - Google Patents

Abstract

PURPOSE:To provide the cooling apparatus and the cooling method, of a wafer, wherein the temperature of the wafer can be cooled simply and rapidly in the cooling apparatus and the cooling method, of the wafer, which are used in the manufacturing process of a semiconductor device. CONSTITUTION:The title apparatus is provided with the following: a cooling plate 1 which is cooled by means of a cooling device 2 and in which a wafer 11 is mounted on its surface; a chamber 3 which forms a hermetically sealed space when it is brought into close contact with the peripheral part of the cooling plate 1; a holder 10 which holds the wafer 11 by keeping a definite interval from the surface of the cooling plate 1; a pressure sensor 4 which detects a pressure inside the chamber 3; a valve 5, for vacuum use, which is installed in the chamber 3; a metering valve 7 and a valve 6, for nitrogen use, which are installed in the chamber 3; and a temperature sensor 8 which detects a temperature inside the chamber 3. The title apparatus is constituted so as to provide a controller 9 which controls the valve 5 for vacuum use and the valve 6 for nitrogen use by means of the pressure sensor 4 and the temperature sensor 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to improvements in a wafer cooling device and a cooling method used in a semiconductor device manufacturing process.

In recent years, the temperature control of a wafer in the manufacturing process of a semiconductor device is required to be strictly performed in order to ensure the uniformity and reproducibility of the process. Under the circumstances as described above, there is a demand for a wafer cooling device and a cooling method capable of ensuring uniformity and reproducibility when cooling a wafer.

[0003]

2. Description of the Related Art A conventional wafer cooling device and cooling method will be described in detail with reference to FIG. As shown in FIG. 2, a conventional wafer cooling device has a wafer 11 placed on the surface of a cooling plate 21, and a cooling device 22 cools the wafer 11 to a preset cooling temperature in a cooling water passage 21a of the cooling plate 21. The wafer 11 is cooled through the cooling plate 21 by flowing the generated cooling water.

In this case, since the temperature of the cooled wafer 11 changes with time along an exponential curve as shown in FIG. 3, it takes a long time for the temperature of the wafer 11 to reach the set temperature. is there.

[0005]

In the conventional wafer cooling device and cooling method described above, the cooling water cooled to the cooling set temperature of the wafer is flowed into the cooling water passage of the cooling plate to cool the cooling plate. Then
Since the wafer placed on this cooled cooling plate is going to be cooled, it takes a long time for the temperature of the wafer to reach the set temperature because the time series change of the temperature of the wafer follows the exponential curve. There was a problem.

It is an object of the present invention to provide a wafer cooling device and a cooling method capable of easily and rapidly cooling the temperature of a wafer under the above circumstances.

[0007]

A wafer cooling device of the present invention cools by a cooling device, and a cooling plate on which a wafer is placed and a peripheral portion of the cooling plate are brought into close contact with each other to form a sealed space. The chamber to be formed, the holder that holds the wafer at a constant distance from the surface of the cooling plate, the pressure sensor that detects the pressure in the chamber, the vacuum valve provided in the chamber, and the chamber The throttle valve and the valve for nitrogen, the temperature sensor for detecting the temperature in this chamber, the pressure in this chamber detected by this pressure sensor, and the temperature in this chamber detected by this temperature sensor And a controller for controlling the nitrogen valve.

The wafer cooling method of the present invention is a cooling method carried out by using the above-mentioned wafer cooling device, in which the wafer is placed on the holder of this cooling plate, and this chamber is brought into close contact with this cooling plate, and this pressure is applied. The controller operates by the pressure detected by the sensor to open the vacuum valve and exhaust the air in the space formed by this chamber and the cooling plate, and the pressure detected by this pressure sensor and the temperature detected by this temperature sensor. The temperature is used to operate the controller to open the nitrogen valve, the throttle valve is used to adiabatically expand the nitrogen to cool the inside of the chamber, and the temperature detected by the temperature sensor is used to operate the controller to operate the nitrogen Close the valve and lower the holder to remove the wafer from the cooler. Configured to include a step of adhering the Gupureto.

[0009]

That is, in the present invention, a chamber for covering the surface of the cooling plate to form a closed space is provided, the space is evacuated, and nitrogen at high temperature and high pressure is adiabatically expanded by the throttle valve to rapidly cool the wafer. After that, the wafer is brought into close contact with the cooling plate cooled to the cooling set temperature to cool the temperature of the wafer to the cooling set temperature, so that the cooling time can be significantly shortened as shown in FIG.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to FIG. FIG. 1 is a diagram showing a wafer cooling device according to an embodiment of the present invention.

As shown in FIG. 1, a wafer cooling device according to an embodiment of the present invention is provided with a holder 10 for holding a wafer 11 at a constant interval on the surface of a cooling plate 1. The chamber 3 is closely attached to the periphery of the to form a sealed space.

Cooling water flow path 1a of this cooling plate 1
Cooling water cooled to the cooling set temperature of the wafer 11 by the cooling device 2 is flown therein to cool the cooling plate 1.

The chamber 3 is connected to the chamber 3 via a pressure sensor 4 for detecting the pressure in the space, a vacuum valve 5 provided in a pipe for exhausting air in the space, and a throttle valve 7. Nitrogen valve 6 installed in the nitrogen pipe
And are provided.

A controller 9 is provided which operates by the pressure detected by the pressure sensor 4 to control opening / closing of the vacuum valve 5 and the nitrogen valve 6. In order to cool the wafer using this wafer cooling device, the wafer 11 is placed on the holder 10 at a constant interval on the surface of the cooling plate 1 and the vacuum valve 5 is opened to exhaust the air in this space. However, when the pressure sensor 4 detects that the pressure in this space has reached the specified pressure, the controller 9 operates to open the valve 6 for nitrogen, so that the nitrogen supplied to the nitrogen pipe is released. Adiabatic expansion is performed by the throttle valve 7 to rapidly reduce the temperature of this space, and the wafer 11 is rapidly cooled along the cooling curve of the present invention shown in FIG.

When the temperature sensor 8 detects that the temperature of the wafer 11 has been cooled to near the preset cooling temperature, the controller 9 is activated and the holder 10 is lowered so that the wafer 11 is placed on the surface of the cooling plate 1. It becomes possible to maintain the temperature of 11 at the cooling set temperature.

[0016]

As is apparent from the above description, according to the present invention, there is an advantage that the temperature of a wafer can be efficiently and rapidly cooled by a very simple structure change, which is extremely economical and It is possible to provide a wafer cooling device and a cooling method that can be expected to improve reliability.

[Brief description of drawings]

FIG. 1 is a diagram showing a wafer cooling device according to an embodiment of the present invention,

FIG. 2 is a diagram showing a conventional wafer cooling device,

FIG. 3 is a diagram showing a wafer cooling curve,

[Explanation of symbols]

1 is a cooling plate, 1a is a cooling water flow path, 2 is a cooling device, 3 is a chamber, 4 is a pressure sensor, 5 is a vacuum valve, 6 is a nitrogen valve, 7 is a throttle valve, 8 is a temperature sensor,
9 is a controller, 10 is a holder, 11 is a wafer,

Claims (2)

[Claims] 1. A cooling plate (1) which is cooled by a cooling device (2) and has a wafer (11) mounted on the surface thereof.
And a chamber (3) that forms a sealed space by closely contacting the periphery of the cooling plate (1), and a holder that holds the wafer (11) at a constant distance from the surface of the cooling plate (1). (10) and a pressure sensor (4) for detecting the pressure in the chamber (3)
A vacuum valve (5) provided in the chamber (3), a throttle valve (7) provided in the chamber (3) and a nitrogen valve
(6) and a temperature sensor (8) for detecting the temperature in the chamber (3)
And the pressure in the chamber (3) detected by the pressure sensor (4) and the chamber (3) detected by the temperature sensor (8)
A wafer cooling device comprising: a controller (9) for controlling the vacuum valve (5) and the nitrogen valve (6) according to the internal temperature. 2. A cooling method performed by using the wafer cooling device according to claim 1, wherein the wafer is attached to the holder (10) of the cooling plate (1).
(11) is placed, the chamber (3) is brought into close contact with the cooling plate (1), and the controller (9) is actuated by the pressure detected by the pressure sensor (4) to vacuum valve.
Open (5) to open the chamber (3) and cooling plate.
Discharging the air in the space formed by (1), the pressure detected by the pressure sensor (4) and the temperature sensor
A step of operating the controller (9) according to the temperature detected by (8) to open the nitrogen valve (6), and adiabatically expanding nitrogen by the throttle valve (7) to cool the chamber (3). And the temperature detected by the previous temperature sensor (8)
(9) actuating to close the nitrogen valve (6) and lowering the holder (10) to bring the wafer (11) into close contact with the surface of the cooling plate (1). A method for cooling a wafer.