JPS62166537A - wafer stage - Google Patents

Abstract

PURPOSE:To prevent a wafer from being contaminated or damaged due to its drop by supporting the wafer by a pin when placing it, and attracting fixedly the wafer by an aspirator provided on a wafer stage when fixing it to eliminate the lateral slip of the wafer when placing it. CONSTITUTION:Three or more pins 2 rounded at the ends are projected from holes formed on the upper surface of a wafer stage 1 having a flat upper surface. Weak springs 3 for lifting the pins 2 upward are disposed under the pins 2, and the lifting forces of the pins 2 are regulated by adjusting screws 4 for supporting the springs 3. The tension of the spring 3 is of the degree that is is lightly sunk when placing a wafer 5 but to maintain the height not to cause the wafer to lateral slip. The hole of an aspirator 6 is provided at the center of the stage 1. When the wafer is placed on the stage 1, the wafer 5 is supported to the pin 2, and does not laterally move at all. The wafer 5 is completely fixed without damage.

Description

[Detailed Description of the Invention] [Required] A protruding pin is provided on the upper surface of the wafer stage to prevent the wafer from sliding sideways when the wafer is placed on it.

[Industrial application field]

The present invention relates to the structure of a wafer stage.

Semiconductor wafers undergo many processing and inspection steps on a wafer stage of a dedicated machine before the wafer process is completed.For example, microscopes, aligners, steppers, probers, etc. all have dedicated wafer stages. ,
Various methods have been used to fix it.

However, regarding the operation up to the fixation of the conventional one,
It required extreme caution and was by no means simple or safe.

[Conventional technology]

Conventional wafer stages have a smooth top surface, so when a wafer is placed on it, it rests on a thin layer of air and is extremely prone to slipping laterally, resulting in the wafer falling off the wafer stage and causing contamination. This caused damage.

Furthermore, in order to prevent side-slipping, there are some devices in which narrow concentric grooves are carved on the top surface of the wafer stage, but the effect cannot be said to be sufficient.

Therefore, there has been a demand for something that does not cause wafer skidding.

[Problem that the invention seeks to solve]

Conventional wafer stages tend to cause wafers to skid when placed on them, so this is prevented.

[Means for solving problems]

The solution to the above problem is to have three or more pins that protrude upward from holes provided on the upper surface of the wafer stage whose upper surface is flat, and whose protruding parts sink into the wafer stage when pressed from above. This is achieved by the wafer stage according to the present invention, in which when the wafer is placed, it is supported by the pins, and when it is fixed, the wafer is sucked and fixed by an aspirator provided on the wafer stage.

(Function) According to the present invention, when a wafer is placed on a wafer stage, the wafer is held by the tips of a plurality of pins at a height that reaches an air layer thickness that causes sideways sliding. Furthermore, when a wafer is attracted by an aspirator, the pins have a weak pushing force, so they are pushed down by the wafer and sink into the wafer stage, so that the wafer is completely fixed tightly to the wafer stage.

〔Example〕

FIG. 1 is a schematic cross-sectional view of a wafer stage in the present invention.

In the figure, 1 is a wafer stage with a flat upper surface, and this wafer stage 1 has three or more pins 2 with rounded tips of about 0.5 mm extending from holes provided on the upper surface.
It's out. Below this pin 2 is a weak spring 3 that pushes up this pin 2, and the pushing force of the pin 2 is adjusted by adjusting the screw 4 that supports the spring 3.

The strength of the spring 3 is such that it sinks slightly when the wafer 5 is placed on it, but maintains a height that does not cause the wafer to slide sideways, and does not damage the wafer when it is pressed against the wafer stage. be.

Further, the wafer stage 1 has an opening for an aspirator 6 at the center thereof.

When a wafer is placed on wafer stage 1 as described above,
The wafer 5 is supported by the pins 2 and does not slip at all. Furthermore, the wafer 5 is completely fixed and is not damaged.

〔Effect of the invention〕

As explained in detail above, according to the wafer stage according to the present invention, there is no side slipping when placing a wafer, and
It is possible to prevent wafer contamination and damage due to dropping.

[Brief explanation of drawings]

FIG. 1 is a schematic cross-sectional view of a wafer stage in the present invention. In the figure, 1 is a wafer stage, 2 is a pin, 3 is a spring, 4 is a screw, 5 is a wafer, 6 is an aspirator

Claims (1)

[Claims] Three or more pins (3 or more) protruding upward from holes provided in the upper surface of the wafer stage (1), the upper surface of which is flat, whose protrusions sink into the wafer stage (1) when pressed from above.
2), and when the wafer (5) is placed, the pins (
2) When supporting and fixing, use the wafer stage (1).
A wafer stage characterized in that a wafer (5) is suctioned and fixed by an aspirator (6) provided in ).