JP2740594B2 - Wafer holder for cleaning and etching - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning / etching wafer holder used for cleaning or etching a semiconductor wafer in a semiconductor product manufacturing process.

[0002]

2. Description of the Related Art In a semiconductor product manufacturing process, a semiconductor wafer is cleaned and etched. In such a process, a resin wafer holder capable of accommodating a large number of semiconductor wafers is used. Is done.
For example, in Japanese Patent Application Laid-Open No. 61-189647, a large number of elongated guides forming a pair on the inner surface side of the holder main body are provided in parallel to form a groove, and the lower part of the main body also corresponds to the guide. A grooved support portion is provided, a semiconductor wafer is inserted into the groove of the guide and the support portion, a base having a cylindrical surface is provided below the holder, and the wafer holder is swung and the wafer is swung. Is disclosed.

In cleaning and etching, the wafer holder is rotated or rocked to improve the uniformity. The rotation and swing have effects such as quickly removing bubbles generated during processing and facilitating liquid exchange near the wafer, thereby increasing the uniformity of processing. However, in the case of the wafer holder disclosed in the above publication, it is practically impossible to rotate the wafer holder because the wafer falls off. Therefore, in order to improve the uniformity, it is necessary to intensify the swing of the wafer holder, but the wafer to be cleaned / etched reciprocates like a pendulum in the wafer holder, and when the reaction is severe, Removal of bubbles generated during processing and liquid exchange near the wafer are performed only insufficiently, and as a result, cleaning and etching uniformity within the wafer surface, particularly at the edge of the wafer, cannot be ensured.

Such disadvantages can be alleviated to some extent by making the wafer holder rotatable, but the wafer is caught in the wafer holding groove in the holder and does not rotate, or during cleaning / etching. It occurs sporadically that the generated air bubbles adhere to the surface and the wafer to be cleaned is pressed upward and the rotation of the wafer is suppressed.

[0005]

SUMMARY OF THE INVENTION The present invention solves the above problem by providing a mechanism for preventing the floating of a wafer to be lifted and for reliably rotating the wafer to be processed in the holder to the wafer holder. An object of the present invention is to provide a cleaning / etching wafer holder capable of performing stable cleaning or etching stably.

[0006]

The cleaning / etching wafer holder of the present invention comprises at least two or more fixed holding rods and one or more movable holding rods for holding a wafer.
At least one of the fixed holding rod or the movable holding rod is attached so that the wafers are separated from each other so as not to fall off, and the pair of opposed side plates are separated from each other.
At least two of the fixed holding rods
The book is provided with a groove for holding a wafer, the movable holding rod is movable in a direction parallel to the side plate, and the side plate is
Is provided with a rotation support portion .

[0007]

The specific structure and operation of the present invention will be described below with reference to the drawings.

FIGS. 1, 2, and 3 show an example of the wafer holder of the present invention, and are an external view and two sectional views. FIG. 2 is a side sectional view, and FIG. 3 is perpendicular to the plane of FIG.
It is sectional drawing showing the cross section which passes along S 'line. As shown, the wafer holder main body includes a pair of side plates 3.
A fixed holding rod 1 and a movable holding rod 2 are attached to the side plate 3. The side plate 3 has a rotation support 4. Fixed holding rod 1
Is provided with a groove for holding the wafer 5. In the case of the movable holding rod 2, the side plate 3 is provided with a hole 6 having a diameter larger than the diameter of the rod.
It can move freely in the hole 6. In addition, at least one of the fixed holding rod and the movable holding rod is removable so as to facilitate loading and unloading of the wafer to be cleaned.

FIG. 4 shows the position of the wafer 5 to be cleaned when the wafer holder is rotated. The wafer 5 before cleaning or etching is in a state represented by A in FIG. All the wafers 5 set in the grooves are in contact with the lower side due to gravity. When the wafer holder is rotated, the wafer 5 is brought into the state shown in FIG. 4B by gravity, and the wafer 5 rotates by the clearance between the wafer and each holding rod. Further, the movable holding rod 2 also moves freely in the hole 6 of the side plate 3 with the rotation of the wafer holder, and pushes the wafer 5 downward. When the wafer holder is further rotated, C in FIG.
And D, and the wafer 5 can be surely rotated with the rotation of the wafer holder. In the conventional wafer holder, bubbles generated by the cleaning or etching reaction adhere to the wafer 5 and the rotation is hindered, and the uniformity of cleaning and etching may be impaired. In addition, the cleaning / etching wafer holder of the present invention in which the movable holding rod 2 pushes down the peripheral surface of the wafer 5 is extremely effective, and the wafer 5 can be surely rotated. Further, in the conventional wafer holder, the wafer 4 was pinched in the groove provided in the fixed holding rod 1 and the rotation was hindered in some cases, resulting in uneven cleaning and etching. Such a phenomenon does not occur in the holder for cleaning and etching described above, and unevenness does not occur. Note that a material having a large specific gravity, such as Teflon, is suitable as a material for the movable holding rod.

As described above in detail, in the cleaning / etching wafer holder of the present invention, the wafer is always stably rotated in the holder only by rotating the wafer holder, so that the cleaning and etching conditions are not uniform. It does not become.
On the other hand, the rotation of the wafer may be impossible or difficult with the conventional wafer holder, and the situation of cleaning and etching may be uneven.

[0011]

EXAMPLE After a silicon wafer roughly polished in a lapping step was washed, it was set on a wafer holder shown in FIG. The holder of FIG. 1 is the wafer holder of the present invention.
Next, a hydrofluoric acid solution (50% hydrofluoric acid: 70% nitric acid: 100%)
The holder on which the wafer was set was immersed in a mixed acid obtained by mixing acetic acid at a volume ratio of 3: 5: 3), and etching was performed while rotating and rocking. For comparison, a similar test was performed on a wafer holder having no movable holding rod. After rinsing with ultrapure water, it was taken out of the holder and dried, and the presence or absence of uneven etching was examined.

When the wafer holder of the present invention is used, no etching unevenness occurs at all, but in the comparative example, etching unevenness was sporadic. Further, there was also a difference in the shape after etching, and when the wafer holder of the present invention was used, there was almost no difference for each wafer.

As described above, in the cleaning / etching wafer holder of the present invention, etching occurs uniformly, and the difference between wafers is small.

As described in detail above, according to the cleaning / etching wafer holder of the present invention, the uniformity and stability of the cleaning or etching process are increased, and the surface quality after the wafer processing is stabilized.

[Brief description of the drawings]

FIG. 1 shows an example of a cleaning / etching wafer holder (external view) of the present invention.

FIG. 2 is a side sectional view of the holder shown in FIG. 1;

FIG. 3 is a sectional view of the holding unit shown in FIG. 1;

FIG. 4 is a position diagram of a wafer to be processed when the cleaning / etching wafer holder of the present invention is used.

[Explanation of symbols]

1 ... fixed holding rod, 2 ... holding rod, 3 ... side plate,
4 ... rotation support part, 5 ... wafer, 6 ... hole.

Claims (1)

(57) [Claims] At least two or more fixed holding rods and one or more movable holding rods for holding a wafer are spaced apart from each other so as not to drop the wafer, and a pair of opposed side plates are formed. At least one of the fixed holding rod and the movable holding rod is detachable, at least two of the fixed holding rods are provided with grooves for holding a wafer, and the movable holding rod is attached to the side plate. and movable in a direction parallel to, and rotate in the side plates
A wafer holder for cleaning / etching, comprising a support portion .