JPS5850742A - Apparatus for wafer washing and drying - Google Patents

Abstract

PURPOSE:To prevent wafer re-contamination and to improve the washing effect by providing the inside of a washing container's side plate with a cylindrical filter surrounding the outer circumference of a rotary frame and forcibly discharging a foggy mixed gas of a washing solution with an external exhaust fan. CONSTITUTION:With a turntable 6 rotated at a slow speed a washing solution is injected through a nozzle 14, evenly washing a wafer 10 on the turntable. Most of the washing solution is passed through a filter 34, while the remainder is forcibly discharged in a foggy state with an exhaust fan 33 through an exhaust port 30, and exhaust pipes 31, 32. When the washing of the wafer 10 is completed, a drying gas is injected from the nozzle 14, and at the same time the turntable 6 is rotated at a high speed. Residual solution adhering to the wafer 10, a wafer accommodating tool 9 and a rotary-frame 8 are blown away by centrifugal force and are dried by the drying gas. The solution become a foggy mixed gas, which is passed through the filter 34 and is forcibly discharged with the exhaust fan 33.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a semiconductor wafer cleaning and drying apparatus that accommodates a large number of semiconductor wafers, rotates them, cleans them, centrifugally dehydrates them, and dries them.

The yield in the manufacturing process of semiconductor products is greatly influenced by the cleanliness of the wafer surface before the wafer processing process. For this reason, before each processing step, a cleaning and drying device is used to remove dust and dirt from the wafer surface.

A conventional wafer cleaning and drying apparatus is shown in a vertical cross-sectional view in FIG. (1) is a cylindrical cleaning container with an open top, supported on a stand (not shown) in a vibration-proof manner, and provided with an exhaust port (2) at the bottom. (3) is an electric motor that is supported on the bottom side of the washing container (1) by means of a support rod (<6), and the shaft end of the rotating shaft (4) passes through the center of the bottom and extends upward. Reference numeral 6) is a single table which is fixed to the shaft end of the rotating shaft (4) and rotated, and mounting seats (7) are fixed to the upper surface at a plurality of positions at equal intervals in the circumferential direction. (8) is a rotating frame fixed on each mounting seat (7),
A plurality of accommodating portions (8a) are arranged on the inside at equal intervals in the circumferential direction, and an exclusion hole (8b) is bored in the back. (9) is a plurality of storage tools that are fitted and held in each storage part (8a) from the inside, and wafers 〇〇 are inserted and stored in the multi-stage radial holding grooves (9a) with gaps between the top and bottom. There is an exclusion hole (9b) on the leg and back.
) has been set. (The lid is placed over the washing container (1) via the bag 01, and the nozzle mounting rod is attached to the center of the lower surface of this lid and extends downward, and is located at the center of the rotating frame (8). , a plurality of nozzles are fixed, and the communication hole (13a) communicates with these nozzles.(I@ enters the lid (ll) from the outside.
) is a connecting pipe connected to

The cleaning and drying of the wafer αQ using the conventional apparatus described above was performed as follows. First, the turntable (6) is rotated at low speed by the electric motor (3), and cleaning liquid is sprayed from each nozzle H. Each wafer QO is rotated while being cleaned by the sprayed cleaning liquid. When cleaning is finished, the electric motor (3
) The turntable (6) rotates at high speed to scatter the cleaning liquid adhering to the surface of the wafer QQ outward by centrifugal force, and at the same time blows out drying gas from the nozzle 04) to clean the surface of the wafer 01. Dry. At this time, the sprayed cleaning liquid mixes with the drying gas, becomes a mist, and is discharged from the exhaust port (2) at the bottom of the cleaning container (1).

However, in the conventional apparatus, the drying gas ejected from the nozzle (14) flows through the wafer 01 section and along the inner wall of the cleaning container (1) behind the wafer 01. 8) and the storage tool (9) while rotating, most of it is discharged from the exhaust port (2), but some of it flows upward as shown by arrow A and is discharged from the lid ( II). For this reason, the inner surface of the side plate (la) of the cleaning container (1) and the lid (8
The cleaning solution that had adhered to and contaminated the wafer (10) circulated in the form of mist, and re-adhered to and contaminated the surface of the cleaned wafer (10).

In this invention, a cylindrical filter surrounding the outer circumference of the rotating frame on the turntable side is provided inside the side plate of the cleaning container, and the atomized mixture of cleaning liquid from the wafer storage tool side held by the rotating frame is filtered. It is an object of the present invention to provide a wafer cleaning/drying apparatus which passes through the filter and forcibly exhausts air from the cleaning container using a large exhaust fan installed outside to prevent wafer re-contamination, enhance the cleaning effect, and improve yield. The purpose is

FIG. 2 is a vertical cross-sectional view of an embodiment of the present invention, the vacuum cleaning device (3L(6) ~QQ-02!J").
” (I@-(8'a) *(8b)*(9a), (9
b) is the same as the conventional device described above.

Qυ is a cleaning container with the above opening, and a cylindrical side plate (21a
) is provided with a bottom plate (211)). (stomach)
is a partition plate provided at the bottom of the cleaning layer, and the handle is a bottom plate (a).
lb) is a drain pipe that is connected to the drain port (goods) and discharges the cleaning solution, (c) is an outlet pipe that is arranged on the bottom plate (2xb) and the end reaches the drain port e4@, and ii) is installed on the partition plate ■. This is a communication pipe that is attached in the direction of the pipe and communicates with the outlet pipe (c), each of which has a plurality of pipes connected in the circumferential direction, and guides the flowing cleaning liquid downward. An electric motor (3) is supported on the bottom plate (21b) via a support frame 4, and the rotary shaft of the electric motor passes through the bottom plate (21b) and fixes the turntop (6). 0... are a plurality of exhaust ports provided on the side plate (21a), to which exhaust pipes CI,) are connected.

■Exhaust fan connected to these exhaust pipes, (to)
is a cylindrical piece that surrounds the outer circumference of the rotating frame (8) with a gap, is arranged with a gap along the inner surface of the side plate (21a) of the cleaning container, and is fixed on the partition plate ■. A filter collects the cleaning liquid and causes it to flow downward. (To) is a lid that is placed over the cleaning container ψυ through the packing H), which closes the gap with the filter through the packing H), and the nozzle mounting rod (11) is attached to the center of the bottom surface. The lower end of the drain pipe is connected to a U-shaped bent pipe if necessary to prevent suction by the exhaust fan.

The cleaning and drying of the wafer Qt1 by the apparatus of the above embodiment is performed in the same procedure as the conventional apparatus. First, the turntable (6) is rotated at low speed, and the cleaning liquid is simultaneously jetted from each nozzle H. Each wafer αQ is evenly cleaned with the cleaning liquid while being rotated. At this time, the exhaust fan (2) is rotated, and the cleaning liquid that has passed through the four parts of each wafer passes through the filter (2), where most of it is collected, and the remainder becomes a mist. ]), to) to the exhaust fan) Next, when the cleaning of the wafer α is completed, drying gas is ejected from each nozzle, and at the same time the turntable (6) rotates at high speed. and wafer QQ,
The residual cleaning liquid adhering to the storage tool (9) and rotating frame (8) is blown off by centrifugal force and dried by drying gas. The residual cleaning liquid blown away at this time is turned into a mist mixture by the dry gas, passes through the filter, and is forcibly discharged by the exhaust fan.

As described above, according to the present invention, the outer circumference of the rotating frame is enclosed within the cleaning container, cylindrical filters are arranged with a gap between both sides, and the exhaust is discharged through the outlet provided on the side plate of the cleaning container. Since the fan is connected, the cleaning liquid remaining on the wafer side becomes a mist-like mixture due to the high-speed rotation and the jetting of dry gas, which is forcibly discharged from the exhaust port through the filter 5, and the cleaning liquid is rotated as before. There is no turning around in the gap between the frame and the side plate of the cleaning container, which prevents wafer re-contamination, improves the cleaning effect, and improves the yield in the next process6.

[Brief explanation of the drawing]

Figure 1 is a vertical cross-sectional view of a conventional wafer cleaning and drying device;
The figure is a longitudinal sectional view of a wafer cleaning and drying apparatus according to an embodiment of the present invention. 3... Electric motor, 6... Turntable, 8... Rotating frame, 9... Storage tool, 10... Wafer, 13
... Nozzle mounting rod, 14... Nozzle, 21... Washing container, 21a... Side plate, 30... Discharge port, 3L3
2... Exhaust pipe, 33... Exhaust fan, 34... Filter, 35... Lid. Note that the same reference numerals in the drawings indicate the same or equivalent parts. Agent Makoto Kuzuno (1 other person) Procedural amendment (voluntary) January 41, 1986 To the Commissioner of the Japan Patent Office 1. Indication of the case Patent application Sho AS-XSOSTA No. 2 and 2. Title of the invention Wafer washed dry grain yield 3. "Detailed Description of the Invention" column of the amended person's specification. 6. Contents of amendment (1) - Changed "supported" in line 16 of page 2 of the specification to "
"Supported" is corrected. (2) Correct “Turntable (4)” on page 4, line 92 of the specification by “Turntable +61 JK.”

Claims (1)

[Claims] A cleaning container with a cylindrical shape and an open top covered with a lid, a rotating frame fixed to a rotating turntable disposed below the cleaning container, and a rotating frame with a circumference attached to the rotating frame. A plurality of storage devices are held at equal intervals in the direction and each holds a large number of wafers with vertical gaps, and a plurality of nozzles are installed on the side of the lid and are attached to the center of the bottom surface of the lid. A nozzle mounting rod is located at the center of the axis of the rotary frame, and a nozzle mounting rod for spraying cleaning liquid from each of the nozzles and then drying gas is connected to the outer circumference of the rotating frame, which is shaped like a cylinder, with a gap □. an enclosure, disposed with a gap on the inner periphery of the side plate of the cleaning container, and connected to the filter and a plurality of discharge ports provided on the side plate of the cleaning container;
Ieno cleaning/drying device equipped with an external exhaust fan that forcibly exhausts the atomized mixture of cleaning liquid inside the side plate.