Wet processing apparatus with movable partitioning plate between two processing chambers

In a wet processing apparatus including a first processing chamber for carrying out a first process with first chemicals and a second processing chamber for carrying out a second process with second chemicals, a separation cell is provided between the first and second processing chambers and receives pure water therein. Also, a movable partitioning plate is provided between the first and second processing chambers, to partition the first processing chamber from the second processing chamber. A lower end of the movable partitioning plate is immersed below a surface of pure water of the separation cell.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to a wet processing apparatus used in the 
manufacture of semiconductor devices and liquid crystal display (LCD) 
panels. 
2. Description of the Related Art 
In the manufacture of semiconductor devices and LCD panels, wet processing 
steps for removing contamination therefrom are so essential that the 
manufacturing yield is dependent thereupon. Generally, a wet processing 
step using an alkali solution such as an anmonia water/hydrogen peroxide 
water mixture (APM) is applied to remove nonorganic particles, and a wet 
processing step using an acid solution such as a hydrosulfurous 
acid/hydrogen peroxide water mixture (SPM) or hydrochloric acid/hydrogen 
peroxide water mixture (HPM) is applied to remove metal particles. Also, a 
wet processing step using an alcohol solution such as an isopropyl alcohol 
solution (IPA) is to remove organic particles. 
Two or more of the above-mentioned wet processing steps are often carried 
out in a single wet processing apparatus. 
A prior art wet processing apparatus is formed by a first processing 
chamber for carrying out a first process with first chemicals, a second 
processing chamber for carrying out a second process with second 
chemicals, and a separation cell provided between the first and second 
processing chambers and receiving pure water therein, a partitioning plate 
is fixed between the first and second processing chambers, to partition 
the first processing chamber from the second processing chamber. In this 
case, a lower end of the partitioning plate is immersed below a surface of 
pure water of the separation cell (see JP-A-5-343387). This will be 
explained later in detail. 
In the prior art wet processing apparatus, since a wafer carrier for 
accommodating wafers has to be moved within the separation cell from one 
of the chambers to the other chamber or vice versa, the separation cell is 
large in size. This increases consumption of pure water. In addition, the 
motion of the wafers within the separation cell generates static 
electricity between the wafers and pure water, so that the wafers are 
charged which destroys the function thereof. 
SUMMARY OF THE INVENTION 
It is an object of the present invention to reduce the consumption of pure 
water in a wet processing apparatus. 
Another object is to avoid destruction of the function of wafers processed 
in the wet processing apparatus. 
According to the present invention, in a wet processing apparatus including 
a first processing chamber for carrying out a first process with first 
chemicals and a second processing chamber for carrying out a second 
process with second chemicals, a separation cell is provided between the 
first and second processing chambers and receives pure water therein. 
Also, a movable partitioning plate is provided between the first and 
second processing chambers, to partition the first processing chamber from 
the second processing chamber. A lower end of the movable partitioning 
plate is immersed below a surface of pure water of the separation cell. 
Thus, the separation cell can be reduced in size, which reduces the 
consumption of pure water. 
Also, a supporting bed for supporting a carrier for accommodating wafers is 
fixed to the separation cell. In other words, the supporting bed is not 
moved within the separation cell. As a result, static electricity is not 
generated, and accordingly, the wafers are not charged, thus avoiding the 
destruction of the function of the wafers.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
Before the description of the preferred embodiment, a prior art wet 
processing apparatus will be explained with reference to FIG. 1 (see 
JP-A-5-343387). 
In FIG. 1, reference numeral 1 designates an alkali atomsphere chamber 
including an alkali water cell 11 and a robot 12, and 2 designates an acid 
atmosphere chamber including an acid water cell 21 and a robot 22. Also, a 
separation cell 3 is interposed between the chamber 1 and the chamber 2 
which are partitioned by a partitioning plate 4. 
Pure water is always supplied to the separation cell 3, so that the pure 
water always overflows therefrom. In addition, the lower end of the 
partitioning plate 4 is immersed below the surface of pure water of the 
separation cell 3. Thus, the chamber 1 is completely isolated from the 
chamber 2, so that alkali vapor hardly invades the chamber 2, and acid 
vapor hardly invades the chamber 1. 
Also, a movable supporting bed 31 is provided within the separation plate 
3, thus supporting the wafer carrier 5. 
The operation of moving a wafer carrier 5 from the chamber 1 to the chamber 
2 is explained next. In this case, the supporting bed 31 is located within 
the separation cell 3 on the side of the chamber 1. 
First, the wafer carrier 5 accommodating wafers is moved by the robot 12 
from the alkali water cell 11 to the supporting bed 31. Then, the robot 12 
is evacuated toward the alkali water cell 11. 
Next, the supporting bed 31 is moved within the separation cell 3 toward 
the chamber 2. As a result, the wafer carrier 5 is placed within the 
separation cell 3 on the side of the chamber 2. 
Finally, the wafer carrier 5 is moved by the robot 22 from the separation 
cell 3' to the acid water cell 21. 
In the wet processing apparatus of FIG. 1, since the wafer carrier 5 has to 
be moved within the separation cell 3 from the chamber 1 to the chamber 2 
or vice versa, the separation cell 3 is large in size. For example, the 
width of the separation cell 3 is as much as two times larger than that of 
the wafer carrier 5. This increases consumption of pure water. 
Particularly, when the diameter of wafers is very large, such as 200 m to 
300 m, the consumption of pure water is remarkably increased. 
In addition, the motion of the movable supporting bed 31 within the 
separation cell 3 generates static electricity between the wafers and pure 
water having a large specific resistance, so that the wafers are charged 
which destroys the function thereof. 
In FIGS. 2A, 2B and 2C, which illustrate an embodiment of the present 
invention, the separation cell 3 of FIG. 1 is modified to a separation 
cell 3' which is smaller than the separation cell 3 of FIG. 1. In this 
case, the separation cell 3' is about half of the separation cell 3 of 
FIG. 1. Also, a supporting bed 31' fixed to the separation cell 3' is 
provided instead of the movable supporting bed 31 of FIG. 1. 
Further, a movable partitioning plate 4' is provided instead of the 
partitioning plate 4 of FIG. 1. The movable partitioning plate 4' is moved 
by a movable mechanism 4'a driven by an air cylinder or an oil cylinder 
(not shown). In this case, the movable mechanism 4'a is covered by 
bellows. 
The operation of moving a wafer carrier 5 from the chamber 1 to the chamber 
2 is explained next. In this case, the partitioning plate 4' is located at 
an edge of the separation cell 3 on the side of the chamber 2. 
First, as illustrated in FIG. 2A, the wafer carrier 5 accommodating wafers 
is moved by the robot 12 from the alkali water cell 11 to the supporting 
bed 31'. Then, the robot 12 is evacuated toward the alkali water cell 11. 
In this state, the separation cell 3' is in an alkali atmosphere. 
Next, as illustrated in FIG. 2B, the movable partitioning plate 4' is moved 
to the edge of the separation cell 3' on the side of the chamber 1, while 
the lower edge of the movable partitioning plate 4' is immersed below the 
surface of the separation cell 3'. As a result, the separation cell 3' is 
transferred from the alkali atmosphere to an acid atmosphere. 
Finally, as illustrated in FIG. 2C, the wafer carrier 5 is moved by the 
robot 22 from the separation cell 3' to the acid water cell 21. 
In FIG. 3, which is a partly-cut perspective view of the apparatus of FIGS. 
2A, 2B and 2C, cleaning shower units 6 are provided on the tops of walls 7 
surrounding the separation cell 3'. The cleaning shower units 6 inject 
pure water to the inner faces of the walls 7, so that alkali or acid 
material adhered thereto is washed with the pure water. In addition, the 
pure water is exhausted from a drain pipe 8. Thus, even when alkali 
material and acid material are alternately adhered to the walls 7 and are 
alternately evaporated therefrom, the alkali material hardly mixes with 
the acid material. 
In FIG. 4, which shows consumption of pure water supplied to the wet 
processing apparatuses of FIGS. 1 and FIG. 2A (2B, 2C), the consumption of 
pure water by the apparatus of FIG. 2A (2B, 2C) can be remarkably reduced 
as compared with that by the apparatus of FIG. 1. 
As explained hereinabove, according to the present invention, since the 
separation cell can be reduced in size, the consumption of pure water can 
be reduced. In addition, since the plate for supporting the wafer carrier 
is fixed to the separation cell, the wafers are hardly charged, so that 
the function thereof is hardly destroyed.