JPH01304733A - Semiconductor wafer washer - Google Patents

Abstract

PURPOSE:To wash semiconductor wafers uniformly and efficiently by providing a rotary driving means which is attached to a rotary shaft asymmetrically and rotates while it is touching the lower ends of the respective semiconductor wafers to move them upward while the wafers are made to rotate. CONSTITUTION:Waveform grooves 7 which create swings of wafers 1 placed in a case 2 are provided on a rotary driving means 6 with a pitch corresponding to the pitch of the positions of the wafers 1 in the cage. The rotary driving means 6 is directly attached to a rotary shaft 8 asymmetrically. Therefore, the wafers 1 placed in the cage 2 dipped into a solution bath 3 are made to rotate while they are touching the curved surface of the rotary driving means 6 and moved upward while they are made to slide in the grooves of the cage 2 along with the rotation and, after they are moved to the uppermost positions, they are guided downward by the grooves of the cage 2. At that time, the wafers 1 are made to swing back and forth in accordance with the swings of the grooves 7 formed on the rotary driving means 6 and made to leave the cage 2 the surfaces of the wafers 1 are washed uniformly. With this constitution, washing solution penetrates completely and the whole wafer 1 can be washed uniformly and efficiently.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a semiconductor wafer cleaning apparatus used in a semiconductor device manufacturing process.

[Conventional technology]

A conventional device of this type is shown in FIG. In this figure, 1 is a semiconductor wafer (hereinafter simply referred to as a wafer) that is an object to be cleaned, and 2 is a basket for storing the wafer 1. Grooves are cut on both sides of the basket, and the wafers can be cleaned by the grooves.
is retained.

3 is a liquid tank, 4 is a supply valve for supplying a cleaning liquid such as water into the liquid tank 3, and 5 is a bottom plate provided at the bottom of the liquid tank 3, which allows the supplied cleaning liquid to be transferred to the wafer 1. A number of holes are formed in a predetermined arrangement to create turbulence in the flow on the surface.

Further, FIG. 4 shows another conventional device in which an ultrasonic vibrator 10 is provided at the bottom of the liquid tank 3 in order to improve the cleaning effect.

Next, the operation will be explained.

A cleaning liquid such as water is supplied to the liquid tank 3 by opening the supply valve 4, but this cleaning liquid is constantly supplied under control from the bottom 5 and overflows.

By placing the wafer 1 in the basket 2 there, the flow of cleaning liquid controlled by the bottom plate 5 acts on the surface of the wafer 1, and the surface of the wafer 1 is cleaned.

[Problem to be solved by the invention]

Since the conventional cleaning apparatus is configured as described above, the cleaning liquid must be disturbed by adjusting the bottom plate 5 in order to create a flow on the surface of the wafer 1, and the exchange of the cleaning liquid, that is, the disturbance of the cleaning liquid, is inefficient. It had become. Also, wafer 1
Because the basket remains supported by the heel 2 and does not separate from the heel 2, the cleaning liquid at the connection between the basket 2 and the wafer 1 tends to remain in that area, and when applying ultrasonic waves, etc., it is difficult to remove the cleaning solution. However, there were also problems such as differences in cleaning efficiency within the surface of the wafer 1 due to standing waves.

This invention was made to solve the above-mentioned problems, and it moves the support position of the wafers supported in the opposing grooves of the cage in the cleaning solution, thereby directing the cleaning solution to the contact surface between the wafer and the cage. It is an object of the present invention to provide a semiconductor wafer cleaning device that can uniformly apply standing waves of ultrasonic waves to the wafer while also allowing the ultrasonic standing waves to reach the wafer quickly.

[Means to solve the problem]

In the semiconductor wafer cleaning apparatus according to the present invention, a plurality of semiconductor wafers are arranged side by side at a predetermined pitch in a basket housed in a cleaning liquid in a liquid tank, and the cleaning liquid is supplied from below through a bottom plate to the semiconductor wafer. A cleaning device that cleans semiconductor wafers in a cleaning solution, in which a rotational drive body is installed asymmetrically around the rotation axis, rotating while contacting the lower end of each semiconductor wafer, and moving each semiconductor wafer upward while rotating. It is.

[Effect]

In this invention, as the rotary drive body rotates, the semiconductor wafer randomly floats and sways in the cage, and after the semiconductor wafer moves to the top, it falls without contacting the rotary drive body, and the semiconductor wafer is washed.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view of a semiconductor wafer cleaning apparatus showing an embodiment of the present invention. In this figure, the same reference numerals as in FIGS. 3 and 4 indicate the same parts, and 6 is a ball-shaped wafer that allows the wafer 1 to float and rotate up and down. As shown in an enlarged view in FIG. 2, this rotary drive body 6 has wave-shaped grooves that generate fluctuations at a pitch located between the wafers 1 juxtaposed in the cage 2. 7 is formed and is directly connected to the rotating shaft 8 in an asymmetrical manner. Reference numeral 9 denotes a drive motor that drives the rotating shaft 8. Note that the bottom plate 5 in the embodiment shown in FIG.
Since there is no need to create turbulent flow, the holes formed in the bottom plate 5 may be made at an even pitch.

Next, the operation will be explained.

The liquid tank 3 always maintains a laminar flow and overflows to prevent the cleaning liquid from stagnation. The wafer 1 juxtaposed on the heel 2 submerged in the liquid tank 3 comes into contact with the curved surface of the rotary drive body 6 and rotates as the rotary drive body 6 rotates. Rotation drive body 6
Since the wafer 1 is asymmetrically supported, the wafer 1 slides upward in the groove of the cage 2 as it rotates, and the wafer 1 that has moved to the highest position is guided by the groove of the heel 2 and falls from that position. At this time, the wafer 1 swings back and forth in accordance with the fluctuation of the groove 7 formed in the rotary drive body 6, and becomes separated from the cage 2. Therefore, the surface of the wafer 1 is uniformly cleaned.

Further, when applying ultrasonic waves using the ultrasonic transducer 10, the rotation of the wafer 1 also prevents the influence of a stationary state.

At this time, if the long axis of the rotary drive body 6 is set at 174 degrees above the liquid level, the influence of standing waves three times or more can be completely prevented. It needs to be deep.

Although the cleaning device has been described in the above embodiment, the liquid tank 3 may be a storage tank for chemicals, and the same effect can be obtained even if it is used for processing a chemical in liquid.

Further, the groove 7 formed in the rotary drive body 6 is not necessarily necessary, and the cleaning effect will not change significantly even if it is not provided.

(Effects of the Invention) As explained above, in the present invention, a plurality of semiconductor wafers are placed side by side at a predetermined pitch in a basket contained in a cleaning liquid in a liquid tank, and the cleaning liquid is supplied from below through the bottom plate. In a cleaning device that cleans semiconductor wafers, a rotary drive body is installed at the bottom of the semiconductor wafer in the cleaning solution, which rotates in contact with the lower end of each semiconductor wafer and moves each semiconductor wafer upward while rotating. When the wafers supported by the grooves formed in the cage move, the cleaning liquid easily circulates around the cage, and the entire wafer is cleaned uniformly and efficiently.

Therefore, effects such as being able to reduce the amount of cleaning liquid used and shortening the cleaning time can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of the configuration of a semiconductor wafer cleaning apparatus showing an embodiment of the present invention, FIG. 2 is an enlarged perspective view showing details of the rotary drive body of FIG. 1, and FIGS. 3 and 4 are conventional 1 is a schematic diagram showing the configuration of a semiconductor wafer cleaning apparatus of FIG. In the figure, 1 is a semiconductor wafer, 2 is a basket, 3 is a liquid tank,
4 is a supply valve, 5 is a bottom plate, and 6 is a rotary drive body. Note that the same reference numerals in each figure indicate the same or corresponding parts. Agent Masuo Oiwa (2 others) Figure 1 Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] In a cleaning apparatus that cleans the semiconductor wafers, a plurality of semiconductor wafers are placed side by side at a predetermined pitch in a basket housed in a cleaning liquid in a liquid tank, and the cleaning liquid is supplied from below through a bottom plate, and the semiconductor wafers in the cleaning liquid are Cleaning of a semiconductor wafer, characterized in that a rotational drive body is provided at a lower part of the wafer asymmetrically about a rotating shaft, the rotational drive body rotating in contact with the lower end of each of the semiconductor wafers and moving each of the semiconductor wafers upward while rotating. Device.