JPH07221064A - Semiconductor wafer washing dryer - Google Patents

Abstract

PURPOSE:To obtain a semiconductor wafer washing dryer which can uniformly dry a semiconductor. CONSTITUTION:The title dryer consists of a container 7 for housing a semiconductor wafer 1, a pure-water supply means 8 for supplying pure water into the container 7, a high-temperature inert gas supply means 10 for supplying a high-temperature inactive gas into the container 7, and a vacuum exhaust means 11 for evacuating the container 7 according to the supply of the high- temperature inert gas and reducing pressure.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wafer cleaning / drying apparatus in a semiconductor wafer process.

[0002]

2. Description of the Related Art FIG. 3 is a schematic diagram showing a conventional semiconductor wafer cleaning / drying system. In the figure, 1
Is a semiconductor wafer, 2 is a chemical solution tank in which the semiconductor wafer 1 is immersed in the chemical solution 2a, 3 is a washing tank in which the semiconductor wafer 1 is washed with ultrapure water 3a, and 4 is a drying tank in which the semiconductor wafer 1 is dried. A mechanism for heating the hydrophilic organic solvent 5 with the heater 6 is provided.

Next, the operation will be described. First, the chemical tank 2
The semiconductor wafer 1 soaked in is subjected to processing such as etching and cleaning. Next, it is transferred to the washing tank 3 and the chemical solution 2a
Are washed away with ultrapure water 3a. Subsequently, the organic solvent 5 having hydrophilicity such as isopropyl alcohol is continuously evaporated by the heater 6 in the drying tank 4, and the water remaining on the surface of the semiconductor wafer 1 is replaced by evaporation.
dry. Although three tanks are shown in FIG. 3, the number of tanks may be increased in consideration of the purpose of cleaning and the efficacy. Furthermore, the drying tank 4 is not the steam drying tank described above,
There is also a spin dryer in which a semiconductor wafer is rotated at high speed to drain water.

[0004]

Since the conventional semiconductor wafer cleaning / drying apparatus is constructed as described above, the semiconductor wafer 1 is exposed to the air when it is moved between the tanks and is partially dried, so that it is deposited. There is a problem in that a pattern defect as an object or a spot occurs and the process yield is lowered. Furthermore, the same phenomenon occurs in the final drying tank 4, and there is a problem that unevenness in drying occurs because the water droplets are not sufficiently replaced with the organic solvent 5 or the drying does not proceed uniformly. Even in the spin drying method, the occurrence of dry spots cannot be avoided because there is a time lag in the scattering of water droplets.

The present invention has been made to solve the above problems, and an object thereof is to obtain a semiconductor wafer cleaning / drying apparatus capable of preventing the occurrence of dry spots and improving the process yield.

[0006]

[Means for Solving the Problems] Claim 1 according to the present invention
The semiconductor wafer cleaning / drying apparatus of No. 1 is a container for storing semiconductor wafers, a pure water supply unit for supplying pure water into the container, a high temperature inert gas supply unit for supplying high temperature inert gas into the container, and a high temperature inert gas. It is composed of a vacuum evacuation means for evacuating the inside of the container in accordance with the supply of the active gas.

Further, according to a second aspect of the present invention, a container for housing the semiconductor wafer, a pure water supply means for supplying pure water into the container, and a high temperature inert gas high pressure supply means for supplying high temperature inert gas into the container. And an exhaust means for detecting a state in which the pressure vessel is pressurized to a high pressure by a high temperature inert gas and opening the atmosphere to reduce the pressure.

Further, in claims 3 and 4, claim 1
Alternatively, in addition to the configuration of 2, the chemical liquid supply means for supplying the chemical liquid is provided in the container.

[0009]

In the semiconductor wafer cleaning / drying apparatus according to the present invention, the steps from cleaning to drying are continuously performed in the container, so that there is no movement of the semiconductor wafer in each tank and partial drying is prevented.

Further, abrupt decompression by a vacuum evacuation means at the time of drying or an evacuation means for releasing a high-pressure state to the atmosphere instantaneously dries to uniformly dry the entire surface of the semiconductor wafer and prevent the occurrence of dry spots.

Further, the chemical liquid supply means makes it possible to consistently carry out from the chemical liquid treatment to the drying in the same container.

[0012]

【Example】

Example 1. Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic diagram showing a schematic cross-sectional structure of a semiconductor wafer cleaning / drying apparatus according to an embodiment of the present invention. In the figure, 1 is a semiconductor wafer similar to the conventional example, 7 is a container for accommodating a plurality of semiconductor wafers 1 in a direction perpendicular to the plane of the drawing, here a vacuum container, and 8 is a supply pipe 8a valve 8b communicating with the vacuum container 7 and the like. Pure water supply means for supplying ultrapure water, 9
Is a drain pipe communicating with the vacuum container 7, and 10 is the vacuum container 7.
A high temperature inert gas supply means for supplying a high temperature inert gas, which comprises a supply pipe 10a and a valve 10b communicating with
Reference numeral 1 denotes a vacuum pump, here a vacuum pump, for evacuating the vacuum container 7, and reference numeral 12 denotes a three-way valve provided at a branch portion between the drain pipe 9 and the vacuum pump 11.

Next, the operation will be described. After the semiconductor wafers 1 are aligned and stored in the vacuum container 7, the three-way valve 12
Is opened to the drain pipe 9 side and the valve 8b of the pure water supply means 8 is opened to supply normal temperature ultrapure water into the vacuum container 7 through the supply pipe 8a. As a result, the semiconductor wafer 1 is flushed and washed. At this time, the three-way valve 12 is opened and closed to open the vacuum container 7.
Cleaning may be promoted by controlling the liquid surface inside. After the normal temperature ultrapure water, high temperature ultrapure water of about 85 ° C. is supplied to promote cleaning and prepare for the next drying. 100 ℃ for higher temperature
The above pure steam may be supplied. After the pure water supply is stopped and the pure water is discharged, the valve 10 of the high temperature inert gas supply means 10
b is opened and a high temperature inert gas such as nitrogen heated to 85 ° C. or higher is supplied from the supply pipe 10a. At the same time, the three-way valve 12 is opened toward the vacuum pump 11 to bring the inside of the vacuum container 7 into a depressurized state. As a result, the surface of the semiconductor wafer 1 is evenly dried. Further, by stopping the supply of the high temperature inert gas and continuing the vacuum state, a more complete dry state can be obtained.

Example 2. Further, in the first embodiment, the vacuum container 7
The semiconductor wafer 1 was dried by evacuating the
The same purpose can be achieved by generating a sudden pressure drop. That is, in FIG. 2, the container is a pressurized container 1.
In the same manner as the procedure described in the first embodiment, after cleaning with ultrapure water, drainage is performed, and then high temperature inert gas is supplied from the high temperature inert gas supply means 10. If the exhaust / drain valve 14 is closed and the high temperature inert gas is further supplied, the inside of the pressurizing container 13 becomes a high temperature / high pressure state. This is detected by a detector (not shown), and the exhaust / drain valve 14 serving as exhaust means is continuously detected.
When opened, the inside of the pressure vessel 13 returns to atmospheric pressure at once through the exhaust pipe 15, and the semiconductor wafer 1 is decompressed and expanded at this time.
Is evenly dried.

Example 3. In the above-mentioned Embodiments 1 and 2, the apparatus provides the steps from washing to drying, but the containers 7 and 13 should further be provided with a chemical liquid supply means 17 (not shown) capable of supplying an acid or alkali chemical liquid. This makes it possible to consistently perform processes from chemical treatment to water washing and drying.

[0016]

As described above, according to the first aspect of the present invention, the container for storing the semiconductor wafer, the pure water supply means for supplying the pure water into the container, and the high temperature inert gas for the inside of the container are supplied. 3. A container for storing a semiconductor wafer according to claim 2, which comprises: a high temperature inert gas supply means, and a vacuum evacuation means for evacuating the inside of the container to reduce the pressure in accordance with the supply of the high temperature inert gas. Pure water supply means for supplying pure water into the container, high temperature inert gas high pressure supply means for supplying high temperature inert gas into the container, and detection of the high pressure inside the container due to high temperature inert gas and opening to the atmosphere Since it is constituted by the exhaust means for reducing the pressure, it is possible to obtain a semiconductor wafer cleaning / drying apparatus capable of preventing the occurrence of dry spots and improving the process yield.

Further, according to the third and fourth aspects, in addition to the first or second aspect, the chemical liquid supply means is provided, so that it is possible to consistently carry out from the chemical liquid treatment to the drying, thereby improving the productivity.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a configuration of a semiconductor wafer cleaning / drying apparatus according to a first embodiment of the present invention.

FIG. 2 is a schematic diagram showing a configuration of a semiconductor wafer cleaning / drying apparatus according to a second embodiment of the present invention.

FIG. 3 is a schematic diagram showing a conventional semiconductor wafer cleaning / drying system.

[Explanation of symbols]

 1 Semiconductor Wafer 7 Vacuum Container (Container) 8 Pure Water Supply Means 10 High Temperature Inert Gas Supply Means 11 Vacuum Evacuation Means (Vacuum Pump) 13 Pressurized Container (Container) 14 Evacuation Means (Exhaust Drain Valve)

Claims (4)

[Claims] 1. A container for accommodating a semiconductor wafer, pure water supply means for supplying pure water into the container, high temperature inert gas supply means for supplying high temperature inert gas into the container, and the high temperature inert gas. A semiconductor wafer cleaning / drying apparatus comprising: a vacuum evacuation unit that evacuates the inside of the container according to the supply of an active gas to reduce the pressure. 2. A container for accommodating a semiconductor wafer, pure water supply means for supplying pure water into the container, high temperature inert gas supply means for supplying high temperature inert gas into the container, and inside the container. Is equipped with an exhaust means for detecting a high pressure of the high temperature inert gas and opening the atmosphere to reduce the pressure. 3. A container for housing a semiconductor wafer, a chemical solution supply means for supplying a chemical solution into the container, a pure water supply means for supplying pure water into the container, and a high temperature inert gas in the container. A semiconductor wafer cleaning / drying apparatus comprising: a high temperature inert gas supply means for supplying the gas; and a vacuum evacuation means for evacuating the inside of the container. 4. A container for housing a semiconductor wafer, a chemical solution supply means for supplying a chemical solution into the container, a pure water supply means for supplying pure water into the container, and a high temperature inert gas in the container. 2. A semiconductor wafer cleaning / drying apparatus comprising: a high temperature inert gas supply means for supplying; and an exhaust means for detecting a high pressure inside the container by the high temperature inert gas to open the atmosphere to reduce the pressure.