JPH03142930A - Drying device for semiconductor wafer - Google Patents

Abstract

PURPOSE:To prevent contamination on wafers by a method wherein a cleaning fluid in trench grooves is rapidly dried by making a high-temperature and high- pressure dry air inject on the wafers and the production of colloidal silica due to the reaction of pure water with silicon is eliminated. CONSTITUTION:The air in the atmosphere is first made to pass through a dehumidifier 26 to become a dry air and thereafter, the dry air becomes a dry air of a high pressure of about several atmospheric-pressures by an air compressor 27 and after that, the dry air is made to pass through a heater 28 to become a high-temperature and highpressure air and the air is made to pass through an introducing tube 22, is made to flow in the interior of a dryer main body 21 and is made to inject from nozzles 24 toward the surfaces of wafers 3 on rotors 25. Accordingly, most of water content on the wafers 3 is sprung out by the centrifugal force of the rotation of the rotors 25 and the force of the jets of the high-temperature and high-pressure dry air, but water content in trench grooves is rapidly heated by the jets of the high-temperature and high- pressure dry air 23, is evaporated and is eliminated. Thereby, contamination in the trench grooves is prevented and the highly reliable wafers are obtained.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a drying apparatus for etching and cleaning the surface of a semiconductor wafer, particularly a semiconductor wafer having trench grooves with a narrow opening width formed thereon. It is related to.

[Conventional technology 1] In recent years, the miniaturization of semiconductor integrated circuits has progressed, and semiconductor wafers (
The structure of circuits formed on the surface of wafers (simply called wafers) is becoming more complex. For this reason, it is necessary to ensure that contaminants and unnecessary substances on the wafer surface are removed by cleaning or etching processing, and to rinse and dry the wafer without recontamination by the contaminants that have been removed or foreign substances in the surrounding area. 1 is a schematic configuration diagram showing a conventional cleaning processing apparatus, in which (a) shows a washing process and (b) shows a drying process. In FIG. 2(a), (1) shows the tank of the cleaning processing equipment, and the wafer (3) is inside this cleaning processing tank (1).
) is placed thereon. (4)
A cleaning liquid (or pure water (5)) is stored in the cleaning treatment tank (1). In FIG. 2(b), a cassette (2) for storing wafers (3) in a drying treatment tank (6) is set on a rotor (7).

In order to clean the wafer (3) using such a cleaning tank (1) and drying tank (6), fill the cleaning tank (1) with the processing liquid (4) in advance and place the wafer in it. The cassette (2) containing (3) is immersed in the processing liquid (4).

Then, to increase cleaning efficiency, ultrasonic energy is added to the cleaning solution (4) and wafer (3), and the cleaning treatment tank (
The cleaning liquid (4) in step 1) is replaced with pure water (5) to completely remove the cleaning liquid from the wafer surface.

Next, after setting the cassette (2) containing the wafer (3) in the drying tank (6), the rotor (7) is rotated, and the pure water (5) on the surface of the wafer (3) is shaken by centrifugal force. Dry by cutting. At this time, in order to keep the surface of the wafer (3) clean, clean air is sent in through the intake port (9) and discharged through the exhaust port (10).

[Problems to be Solved by the Invention] In the conventional drying apparatus as described above, the structure of the circuit formed on the surface of the wafer becomes complicated, so that the opening width on the wafer surface is narrow compared to the depth dimension. When grooves (hereinafter referred to as trench grooves) are formed, pure water on the wafer surface flows through the rotor (
Although it is repelled by the centrifugal force of the rotation in step 7), the pure water in the trench remains on the wafer for a long time because it is difficult to dry. As a result, silicon atoms on the wafer surface (
St) and pure water react to form colloidal silica (SiOx)
There is a problem in that the colloidal silica remains as a contaminant within the trench, greatly impairing the performance and functionality of the semiconductor device.

This invention was made to solve the above-mentioned problems, and an object of the present invention is to provide a semiconductor wafer drying device that can dry semiconductor wafers without causing contamination of the semiconductor wafers such as colloidal silica. shall be.

[Means to solve the problem]

The semiconductor evaporator drying apparatus according to the present invention sprays dry air at high pressure and high pressure onto the wafer during the process from cleaning to drying.
This method quickly dries the cleaning solution in the trench, eliminates the formation of colloidal silica due to the reaction between pure water and silicon, and prevents contamination on the wafer.

[Function] In the present invention, high-temperature, high-pressure dry air quickly imparts heat to the pure water in the trench to accelerate drying.

[Example] An embodiment of the present invention will be described below with reference to FIG.

FIG. 1 shows a drying device according to the present invention (21
) is the main body of the drying device, (22) is the high temperature, high pressure drying air (
The introduction pipe 23) has a nozzle (24) for jetting air onto the wafer (3). The wafer (3) is placed on the rotor (25). A dehumidifier (26) is installed in the middle of the introduction pipe (22) to remove moisture from the air at atmospheric pressure.
, an air compressor (27) for making the air high pressure, and a heater (28) for making the air high temperature. (
29) is an outlet for high humidity air after removing moisture from the wafer (3).

Atmospheric air at about 20°C first passes through a dehumidifier (26) to become dry air, then becomes dry air at a high pressure of about several atmospheres by an air compressor (27), and is then turned into dry air by a heater (28). The air becomes high-temperature and high-pressure air at a temperature of 60 to 80 degrees Celsius.
22) into the dryer main body (21), and is ejected from the nozzle (24) toward the surface of the wafer (3) on the rotor (25). Most of the moisture on the wafer (3) is repelled by the centrifugal force of the rotation of the rotor (25) and the force of the jet, but the moisture in the trench is quickly removed by the jet of high-temperature, high-pressure dry air (23). It will be heated and evaporated. The dry air that has removed moisture from the wafer (3) becomes highly humid air and is discharged from the exhaust port (29). Since high-pressure air can contain a larger amount of moisture than low-temperature, low-pressure air, the moisture on the wafer (3) dries faster and is supplied onto the wafer (3) as a jet. , the effect that heat transfer efficiency to the wafer (3) is good and moisture evaporation is further promoted can be obtained.

In addition, in the above embodiment, by slightly tilting the direction of the jet flow from the nozzle (24) in the centrifugal direction of the rotor (25), the wafer (3) is
), it is possible to achieve the effect of speeding up the removal of moisture on the dryer (21). By performing heat conversion with the air, waste heat from the high-temperature, high-humidity air is recovered, and the heater (
The effect of reducing power consumption in 28) can also be obtained.

[Effects of the Invention] As described above, according to the present invention, since the moisture on the wafer is dried by a jet of high-temperature, high-pressure dry air, the inside of the trench groove is quickly dried, and as a result, the trench This has the effect of preventing contamination within the grooves and providing highly reliable wafers.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a drying device according to an embodiment of the present invention, and FIGS. 2(a) and 2(b) are schematic sectional views showing a conventional drying device. In the figure, (3) is the wafer, (21) is the drying device main body, (23) is high temperature, high pressure drying air, (24) is the nozzle, (25) is the rotor, (26) is the dehumidifier, (27) indicates the compressor, (28) indicates the heater, and (29) indicates the discharge port. In addition,

Claims (1)

[Claims] (1) A drying device that cleans a semiconductor wafer with a cleaning solution such as pure water and then dries it with dry air, which is characterized by blowing high-temperature, high-pressure dry air onto the wafer to dry it. Semiconductor wafer drying equipment.