JPH01209740A - Method for positioning semiconductor substrate - Google Patents

Abstract

PURPOSE:To make it possible to align a substrate on the basis of the detected data, by detecting the amount of the eccentricity between the semiconductor substrate and a wafer chuck and the position deviation of an orientation flat with the wafer chuck provided with a line sensor. CONSTITUTION:A line sensor 3 is provided in the radial direction of a wafer chuck 2. A semiconductor substrate 1 is sucked at a position having an amount of eccentricity C with respect to the chuck 2. The chuck 2 and the semiconductor substrate 1 as a unitary body are rotated in the counterclockwise direction with the center of the chuck 2 as the center of rotation. Then, the amount of the received light in the line sensor 3 is changed with respect to the rotating angle. The amount of eccentricity C can be obtained from the difference between the amounts of received beams of light at the rotating angles of 90 deg. and 270 deg.. The position of the center of an orientation flat 1a can be obtained from a rotating angle theta of the maximum amount of the light in the curve of the orientation flat part. When the chuck 2 is rotated in the counterclockwise direction by the rotating angle theta, amounts of eccentricities D and E become D=C.costheta and E=C.sintheta. The substrate 1 is mounted under the state wherein a conveying mechanism 5 is moved by the amount of the eccentricity. The conveying mechanism is returned to the specified position with respect to a wafer chuck 6, and the semiconductor substrate 1 is mounted on the chuck 6.

Description

[Detailed Description of the Invention] [Summary] Regarding the improvement of the method for correcting the eccentricity of the semiconductor substrate and the wafer chuck and positioning the orientation flat, there is provided a semiconductor substrate that can correct the eccentricity of the semiconductor substrate and the wafer chuck and position the orientation flat in a short time. The purpose of the present invention is to provide a positioning method that uses a semiconductor substrate positioning device that includes a wafer chuck having a rotation mechanism, a line sensor, and a transfer mechanism to determine the eccentricity and orientation flat of the semiconductor substrate and the wafer chuck. The position is detected, and based on the position data of the orientation flat of the detection data, the rotation mechanism rotates the wafer chuck to position the orientation flat of the semiconductor substrate at a desired position, and the eccentricity of the detection data is detected. Based on the data, the transport mechanism is positioned and configured to transport the semiconductor substrate to a wafer chuck as a transport destination.

[Industrial application field]

The present invention relates to the handling of semiconductor substrates, and in particular to correction of eccentricity between a semiconductor substrate and a controller and improvement of a method for positioning an orientation flat.

In the processing process of semiconductor substrates, normally, when the semiconductor substrate is first mounted on the wafer chuck, the eccentricity of the semiconductor substrate and the wafer chuck and the position of the orientation flat (hereinafter referred to as orientation flat) are uncertain; In order to handle the semiconductor substrate, the above deviation is necessary.

It is necessary to eliminate the amount of 6 and position the orientation flat.

Conventional methods for positioning semiconductor substrates can be roughly divided into two types: one is an edge contact method, and the other is a non-contact method using spot sensors, etc. These methods are particularly useful in the manufacture of semiconductor devices. In the process, there are quality problems caused by various particles, and the problem that the positioning process is complicated and takes too much time.

Under the above circumstances, there is a need for a semiconductor substrate positioning method that can efficiently correct the eccentricity of the semiconductor substrate and wafer chuck and position the orientation flat in a clean atmosphere.

[Conventional technology]

A conventional method for positioning a semiconductor substrate will be explained with reference to FIGS. 4 and 5.

FIG. 4 is a diagram showing the main parts of the edge contact method. As shown in the figure, the roller 13 of the positioning mechanism is brought into contact with the outer periphery of the semiconductor substrate 11 placed with zero eccentricity with respect to the wafer chuck 12, and in this state, the rotation mechanism 14 of the wafer chuck 12 is rotated. The semiconductor substrate 11 is rotated, and the rotation of the wafer chuck 12 is stopped at the position where the roller 13 is closest to the center of the wafer chuck, thereby positioning the orientation flat l1a.

FIG. 5 is a diagram showing the main parts of a non-contact method using spot sensors. As shown in the figure, the wafer chuck 22
Semiconductor substrate 21 placed with zero eccentricity relative to
Two sets of spot sensors 23 are installed at a position where the orientation flat 21a is to be installed, at a distance shorter than the chord length of the orientation flat 21a, and in this state, the rotation mechanism 24 of the wafer chuck 22 is installed. Semiconductor substrate 2
1, and stop the rotation of the wafer chuck 22 at a position where these two spot sensors 23 operate simultaneously,
The orientation flat 21a is being positioned.

In either case, as described above, it is necessary to perform the positioning of the orientation flat after performing the step of bringing the eccentricity between the semiconductor substrate and the wafer chuck to zero.

[Problem to be solved by the invention]

The problem with the conventional semiconductor substrate positioning methods described above is that in either case, the orientation flat must be positioned after the process of zeroing out the eccentricity of the semiconductor substrate and wafer chuck. This requires two steps, including the subsequent positioning of the orientation flat, and the positioning process takes too much time.

Furthermore, in the case of the contact method, particles such as the semiconductor substrate or coatings attached to the semiconductor substrate may be generated even once.
If the particles adhere to the rollers or the like of the positioning device, there is a risk that they will spread to all semiconductor substrates that will be subsequently positioned.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a semiconductor substrate positioning method that can correct the eccentricity of the semiconductor substrate and wafer chuck and position the orientation flat in a short period of time.

[Means to solve the problem]

The above problem is caused by a wafer chuck with a rotation mechanism,
Using a semiconductor substrate positioning device equipped with a line sensor and a transport mechanism, detect the eccentricity between the semiconductor substrate and the wafer chuck and the position of the orientation flat, and based on the detected data, the position data of the orientation flat. The rotation mechanism rotates the wafer chuck to position the orientation flat of the semiconductor substrate at a desired position, and the transfer mechanism is positioned based on the eccentricity data of the detection data, and the wafer chuck is placed on the destination wafer chuck. The problem is solved by a semiconductor substrate positioning method according to the present invention for transporting a semiconductor substrate.

[Effect]

That is, in the present invention, the wafer chuck is rotated by the rotation mechanism while the semiconductor substrate is placed at an arbitrary position on the wafer chuck, and the line sensor arranged around the periphery of the semiconductor substrate is shielded from light by the semiconductor substrate. is converted into data, and the wafer chuck is rotated based on this orientation flat position data to move the orientation flat position of the semiconductor substrate to a predetermined position, while the semiconductor substrate is transferred to the next wafer chuck based on this eccentricity data. X-Y
After directional positioning, the semiconductor substrate is mounted on the transfer mechanism in this state, the semiconductor substrate is transferred to the destination wafer chuck, and the semiconductor substrate can be placed in the correct position.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 to 3.

As shown in FIG. 1, in one embodiment of the present invention, a semiconductor substrate l is placed at a position having an eccentricity C with respect to a wafer chuck 2.
is adsorbed.

As shown in the figure, the line sensor 3 is provided at a position where the elements of the line sensor 3 are lined up in the radial direction of the wafer chuck 2.

In this state, when the rotation mechanism 4 is driven and the wafer chuck 2 and the semiconductor substrate l are rotated counterclockwise around the center of the wafer chuck 2 as a rotation center, the wafer chuck 2 and the semiconductor substrate l are blocked by the semiconductor substrate l of the line sensor 3. The area of the part changes.

Therefore, the amount of light received by the line sensor 3 changes with respect to the rotation angle as shown in FIG.

As shown in the figure, the amount of light received relative to the rotation angle is minimum when the rotation angle is 90@, maximum when the rotation angle is 270'',
The orientation flat 1a changes as shown in the figure, and shows a smooth curve as a whole.

The amount of eccentricity can be determined from the difference in the amount of light received when the rotation angle is 90 degrees and 270 degrees.

The position of the center 18 of the orientation flat can be determined from the rotation angle of the maximum light amount of the curve of the orientation flat part.

The wafer chuck 2 is rotated counterclockwise by the rotation angle of the center of the orientation flat 1a obtained in this way to fix the wafer chuck 2, and the direction of the orientation flat 1a is determined.

Assuming that the angle of rotation for positioning the orientation flat 1a is θ, the eccentric amounts shown in FIG. 2 have the following values.

D=C-CO5θ, E=C-SINθ To correct these eccentric amounts, the semiconductor substrate 1 is mounted on the transfer mechanism 5 with the position of the transfer mechanism 5 moved by these eccentric amounts, and then the semiconductor substrate 1 is The transport mechanism 5 is returned to the position defined for the wafer chunk 6 on which the semiconductor substrate 1 is placed, and the semiconductor substrate 1 is placed on the wafer chuck 6.

In this way, the wafer chuck 2 is rotated according to the amount of light received by the line sensor 3 to determine the direction of the orientation flat 1a, and the semiconductor substrate l is mounted on the transport mechanism 5 at the position where the amount of eccentricity has been corrected, and the wafer chuck is used for the next process. Since the semiconductor substrate 1 is placed on the transfer mechanism 5 at a specified position on the wafer chuck 6, the eccentricity of the semiconductor substrate l mounted at an arbitrary position on the wafer chuck 2 and the positioning of the orientation flat 1a can be corrected in a short time. It becomes possible to do both at the same time.

〔Effect of the invention〕

As is clear from the above description, according to the present invention, the eccentricity of the semiconductor substrate and the wafer chuck and the positional deviation of the orientation flat can be detected using a wafer chuck equipped with a line sensor having an extremely simple structure. It has advantages such as being able to align semiconductor substrates using data, and can be expected to have significant economic and reliability effects, making it extremely useful industrially.

[Brief explanation of the drawing]

Fig. 1 is a diagram showing the main parts of an embodiment according to the present invention, Fig. 2 is a plan view showing the whole of an embodiment according to the present invention, and Fig. 3 is a diagram showing the rotation angle and line sensor of an embodiment according to the present invention. FIG. 4 is a diagram showing a conventional method for positioning a semiconductor substrate; FIG. 5 is a diagram showing another conventional method for positioning a semiconductor substrate. In the figure, 1 is a semiconductor substrate, 1a is an orientation flat, 2 is a wafer chuck, 3 is a line sensor, 4 is a rotation mechanism, 5 is a transfer mechanism, and 6 is a wafer chuck. Figure 1 is a plan view showing the main parts of an embodiment of the present invention. Figure 2 is a plan view showing the entire embodiment of the present invention. 1 (Al Plan view ('b) Side view A diagram showing a conventional method for positioning a semiconductor substrate. FIG. 4 (a) Plan view (BL Side view) A diagram showing another conventional method for positioning a semiconductor substrate.

Claims (1)

[Claims] A wafer chuck (2) having a rotation mechanism (4);
Using a semiconductor substrate positioning device equipped with a line sensor (3) and a transport mechanism (5), the eccentricity between the semiconductor substrate (1) and the wafer chuck (2) and the position of the orientation flat (1a) are determined. Based on the position data of the orientation flat (1a) of the detected data, the rotation mechanism (4) rotates the wafer chuck (2) to rotate the orientation flat (1a) of the semiconductor substrate (1). The transport mechanism (5) is positioned at a desired position and based on the eccentricity data of the detected data.
A method for positioning a semiconductor substrate, comprising: positioning the semiconductor substrate (1), and then transporting the semiconductor substrate (1) to a wafer chuck (6) as a transport destination.