JPH04221828A - Masking device - Google Patents

Abstract

PURPOSE:To provide a masking device which can easily perform masking work at the time of etching a semiconductor wafer. CONSTITUTION:A semiconductor wafer 1 and backup plate 2 which abuts on the non-etching surface 1a of the wafer 1 are held from both top and bottom sides by means of ring bodies 4 and 5. The ring bodies 4 and 5 are provided with seal members 31, 32, and 33-which cover the outer peripheral edges of the wafer 1 and plate 2 put on another. A binding member 6 constitutes a toggle mechanism with a locking arm 61 and biding lever 62 and binds both ring bodies 4 and 5 when the lever 62 is operated. When the member 6 binds the ring bodies 4 and 5, the backup plate 2 is brought into close contact with the wafer 1 and the seal members 31, 32, and 33 are press-contacted with the outer peripheral edges of the plate 2 and wafer 1 in a liquid-tight state.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a masking apparatus used for etching semiconductor wafers.

0002

[Prior Art] S has excellent strength and is easy to form IC circuits.
A small pressure sensor is manufactured by etching a part of the i-substrate to form a diaphragm. An example of this is shown in FIG. 7. The figure shows the diaphragm forming surface (etched surface) 1b of the Si semiconductor wafer 1,
Each rectangular chip C (right side in the figure) cut out by dicing has its inner peripheral portion etched to form a thin diaphragm C1.

By the way, in such an etching process, conventionally, as shown in FIG. 72 is pasted to isolate it from the etching solution and perform masking. That is,
As shown in FIG. 9, the wafer 1 with the bake plate 72 attached thereto is
A jig 81 installed in the processing tank 8 filled with etching solution L
By performing the etching process while setting the circuit surface 1a, the etching liquid L is prevented from entering the circuit surface 1a. After the processing is completed, the wafer 1 is peeled off from the bake plate 72 and cleaned with an organic solvent or the like.

0004

[Problems to be Solved by the Invention] However, in the conventional masking process described above, it is necessary to manually perform complicated processes such as applying wax, attaching and peeling off the wafer, and cleaning the wax. This had become a bottleneck for rationalization.

The present invention has been made to solve this problem, and an object of the present invention is to provide a masking device that can significantly save labor in the masking process.

[0006]

[Means for Solving the Problems] To explain the structure of the present invention, there is a backup plate 2 provided overlappingly on the non-etched surface 1a of a semiconductor wafer 1, and an outer surface of the overlapping backup plate 2 and the semiconductor wafer 1. The upper ring body 4 and the lower ring body 5 have seal members 31, 32, and 33 covering their peripheries and are in contact with both surfaces thereof, respectively, and these upper ring body 4 and lower ring body 5 are tightly connected. A fastening means 6 is provided for bringing the seal members 31, 32, 33 into pressure contact with the outer peripheral edge in a liquid-tight manner.

In this configuration, when the upper and lower ring members 4 and 5 are brought into contact with both surfaces of the semiconductor wafer 1 and the backup plate 2 which are stacked on top of each other, the seal members 31 and 32 are brought into contact with each other.
, 33 come into contact with the outer peripheral edges of the semiconductor wafer 1 and the backup plate 2. In this state, when the upper and lower ring bodies 4 and 5 are tightened by the tightening means 6, the seal members 31, 32,
33 is in pressure contact with the outer peripheral edge in a liquid-tight manner. Thus, the non-etched surface 1a of the semiconductor wafer 1 is prevented from contacting the etching solution by the back-up plate 2 and the seal members 31, 32, 33 which are in contact therewith, and is masked.

[0008]

[Embodiment] In FIGS. 1 and 2, the masking device includes circular ring bodies 4 made of metal and having the same diameter, which are stacked one on top of the other.
5, and a rubber seal member 31 is disposed in a groove formed on the entire inner circumference of the overlapping surfaces of the upper ring body 4. In the lower ring body 5, rubber seal members 32 and 33 are provided in grooves formed around the inner and outer peripheries of the overlapped surfaces, respectively, and linear grooves are provided on the lower surface at left and right positions. Locking groove 5
1 (only one is shown). The inner diameters of these upper and lower ring bodies 4 and 5 are slightly smaller than the outer diameter of the semiconductor wafer 1.

The semiconductor wafer 1 has a diaphragm forming surface 1b.
with the ring bodies 4, 5 facing upward and a synthetic resin back-up plate 2 of the same diameter in contact with the lower circuit surface 1a.
is sandwiched between. In this state, the sealing members 31 and 32 are in elastic contact with the upper and lower surfaces of the outer periphery of the semiconductor wafer 1, and the sealing member 33 is in contact with the overlapping surface of the upper ring body 4. The periphery is substantially covered. Note that the positioning of the semiconductor wafer 1 is performed by convex claws 52 and 53 (two locations are shown) provided at four locations on the inner peripheral edge of the lower ring body 5.

The upper and lower ring bodies 4 and 5 stacked with the semiconductor wafer 1 sandwiched therebetween are provided with fastening members 6 at left and right positions, respectively.
is installed. Each fastening member 6 is composed of a locking arm 61 and a fastening lever 62 on both sides. A shaft member 63 connecting the two is fitted into the locking groove 51 and locked.

Each of the tightening levers 62 extends in a substantially L-shape along the upper ring body 4, and their tips are connected to each other. The tightening lever 62 has its rotating proximal ends connected by a shaft member 65. Both ends of the shaft member 65 have a large diameter, and a rotating roller 66 is fitted around the outer periphery of the large diameter portion 651. has been done. The rotating roller 66 is in contact with a curved concave surface 4a (FIG. 3) formed on the periphery of the upper ring body 4. here,
The distance between the rotation center OA of the tightening lever 62 (the axis of the shaft member) and the rotation center OB of the rotating roller (the axis of the large diameter part) is m.
The center of rotation OB moves around the center of rotation OA as the tightening lever 62 rotates (arrow in the figure).
.

When the shaft member 63 is locked in the locking groove 51 and the tightening lever 62 is tilted and rotated inward to the ring bodies 4, 5, the rotating roller 66 comes into contact with the curved concave surface 4a. At the same time, the center of rotation OB moves as described above. This process will be explained with reference to FIGS. 4 to 6. In the figure, 3 indicates an equivalent spring of the sealing member, and OC is the rotation center of the locking arm 61 (the axis of the shaft member). As can be seen from the figure,
As the tightening lever 62 is rotated, the center OB becomes the center OA.
Rotate counterclockwise and move beyond the line connecting the centers OA and OC. In this process, the rotation biasing direction by the spring 3 is reversed to realize a toggle mechanism, and the upper ring body 4 is tightly connected to the lower ring body 5, and the seal members 31 and 32 are connected to the semiconductor wafer 1 and the backup plate 2. Seal members 33 are brought into liquid-tight pressure contact with the overlapping surfaces of the upper ring body 4, respectively, on the upper and lower surfaces thereof.

[0013] Thus, the circuit surface 1a of the semiconductor wafer 1 held between the ring bodies 4 and 5 is isolated from the etching solution and masked by the backup plate 2 and the seal members 31, 32, 33 that are in close contact with the circuit surface 1a. Ru.

When the material of the backup board 2 is made of synthetic resin as in the above embodiment, it is possible to prevent the circuit surface 1a from being damaged. In this case, if a material with good releasability such as Teflon is used, the semiconductor wafer 1 and the backup plate 2 can be easily separated.

It is also possible to process two wafers at the same time by bringing the semiconductor wafers 1 into close contact with the upper and lower surfaces of the backup plate 2. In this case, if a porous material is used for the backup plate, the wafers and The air between the backup plates can easily escape and the two can be brought into close contact with each other.

[0016] In addition to the above embodiments, bolts or the like may be used as the fastening member.

[0017]

As described above, the masking device of the present invention eliminates the need for complicated manual operations such as wax application and cleaning as in the prior art, making it possible to significantly save labor in the masking process.

[Brief explanation of the drawing]

[Figure 1] A cutaway side view of the masking device, with the cross section shown in Figure 2.
FIG. 2 is a sectional view taken along line II of FIG.

FIG. 2 is a cutaway plan view of the masking device.

FIG. 3 is a sectional view of a main part of the masking device.

FIG. 4 is a conceptual diagram showing the operation of the fastening member.

FIG. 5 is a conceptual diagram showing the operation of the fastening member.

FIG. 6 is a conceptual diagram showing the operation of the fastening member.

FIG. 7 is a plan view of a semiconductor wafer and a perspective view of a chip.

FIG. 8 is a sectional view showing a conventional example.

FIG. 9 is a sectional view of an etching treatment tank in a conventional example.

[Explanation of symbols]

1 Semiconductor wafer 1a Circuit surface (non-etched surface) 2 Backup plates 31, 32, 33 Seal member 4 Upper ring body 5 Lower ring body 6 Tightening means 61 Locking arm 62 Tightening lever

Claims (1)

[Claims] 1. A backup plate provided overlappingly on a non-etched surface of a semiconductor wafer, and a sealing member covering the outer periphery of the overlapping backup plate and the semiconductor wafer, the sealing member being applied to each of these surfaces. A masking device comprising an upper ring body and a lower ring body that are in contact with each other, and a tightening means for tightly connecting the upper ring body and the lower ring body to bring the seal member into liquid-tight pressure contact with the outer peripheral edge.