JPH0480941A - Positioning of substrate - Google Patents

Abstract

PURPOSE:To make it possible to position a substrate with high accuracy by a compact device by a method wherein two pieces of piezoelectric elements made to touch one side of the substrate are made to displace in the opposite direction to each other, the attitude of the substrate is adjusted, fellow piezoelectric elements arranged on the sides opposed to each other of the substrate are made to displace in the opposite direction to each other and the attitude of the substrate is adjusted. CONSTITUTION:A voltage is first applied to a piezoelectric element 51 and a substrate 1 is moved until it touches piezoelectric elements 52 and 53. The touch can be detected by a change in the voltages of the elements 52 and 53. Here, the elements 52 and 53 are made to displace in the opposite direction to each other and the inclination of the substrate 1, that is, the angle theta of the substrate 1 is adjusted. Then, the elements 52 and 53 are made to displace by the same amount in the same direction and at the same time, the element 51 is made to displace by the same amount as the above in the opposite direction to the elements 52 and 53 and the position in the direction of a Y-axis of the substrate is adjusted. Moreover, piezoelectric elements 54 and 55 are made to displace, the substrate touches the elements 54 and 55 and when the substrate touches the elements 54 and 55, the elements 54 and 55 are made to displace by the same amount in the opposite direction to each other and the position in the direction of an X-axis of the substrate is adjusted.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a method for positioning a substrate on which elements such as a photodiode array (hereinafter abbreviated as PDA) are formed.

<Prior Art> In an optical encoder, the positional accuracy of mounting a substrate on which a PDA is formed greatly affects the ripple of the detection signal.

Conventionally, a mechanical device such as an XY stage has been used to position a substrate on which a PDA is formed.

<Problems to be Solved by the Invention> However, the XY stage has a problem in that fine adjustment of several μm is difficult. Also, since the stage was large, it was difficult to handle.

The present invention was made to solve these problems, and an object of the present invention is to realize a method that can position a substrate with high precision using a compact device.

Means for Solving the Problems> The present invention provides a substrate positioning method for positioning a rectangular substrate at a target position, comprising: bringing a piezoelectric element that is displaced in proportion to an applied voltage into contact with each side of the rectangular substrate; This piezoelectric element has a first piezoelectric element on one side, second and third piezoelectric elements on the other side, and a pair of opposite sides of a rectangle. In this substrate positioning method, a fourth piezoelectric element is arranged on one side and a fifth piezoelectric element is arranged on the other side, and the substrate is positioned in the next step.

(2) Adjusting the inclination of the substrate by displacing the second piezoelectric element and the third piezoelectric element in opposite directions without displacing the first piezoelectric element.

■Displace the second piezoelectric element and the third piezoelectric element by the same amount in the same direction, and displace the first piezoelectric element by the same amount in the opposite direction with respect to the second piezoelectric element and the third piezoelectric element. Y of the board
The process of adjusting the axial position.

(2) A step of adjusting the position of the substrate in the X-axis direction by displacing the fourth piezoelectric element and the fifth piezoelectric element by the same amount in opposite directions.

In the present invention, one piezoelectric element is brought into contact with each of the three sides of the rectangular substrate, two piezoelectric elements are brought into contact with the remaining one side, and two piezoelectric elements are brought into contact with each side. The attitude of the substrate is adjusted by displacing the piezoelectric elements that are in contact with each other in opposite directions. Furthermore, the piezoelectric elements arranged on opposite sides are displaced in opposite directions to adjust the positions of the substrate in the X-axis direction and the Y-axis direction. This positions the substrate.

<Example> Hereinafter, the present invention will be explained using the drawings.

FIG. 1 is a diagram showing an example of the configuration of an apparatus for carrying out the method according to the present invention. In FIG. 1, <a) is a plan view of the device, and FIG. 1(b) is a sectional view taken along the line AA in FIG. 1(a).

In these figures, 1 is a substrate to be positioned, and here it is a rectangular substrate. 2 is a PDA formed on the substrate 1. There are markings 21 to 24 on each side of the PDA 2 that serve as marks when positioning the board.
When positioning, these marks are monitored with a microscope, and the board is aligned so that the mark overlaps the cursor marked on the microscope's monitor screen.

3 is a fixing member to which the substrate 1 is positioned and fixed.

4 is a fixing device in the form of a rectangular frame, and is fixed by another fixing means (not shown). is fixed.

51 to 55 are piezoelectric elements that are attached to the inside of the fixture 4 and have their tips facing inside the frame.

One piezoelectric element is attached to each of the four sides on the inside of the body, and one piezoelectric element is attached to each side, and two piezoelectric elements are attached to each side. These piezoelectric elements are displaced in proportion to the applied voltage, and the displacement can be arbitrarily changed by adjusting the applied voltage.

Using such a device, the substrate is positioned according to the following procedure.

FIG. 2 is an explanatory diagram of the operation. Components in FIG. 2 that are the same as those in FIG. 1 are given the same reference numerals.

First, a voltage is applied to the piezoelectric element 51 and the substrate 1 is moved until it hits the piezoelectric elements 52 and 53. This is because the voltage of the piezoelectric element is proportional to the displacement.
If you monitor the voltage in step 3, you can detect a hit when the voltage changes.

Here, the piezoelectric elements 52 and 53 are displaced in opposite directions to adjust the inclination of the substrate 1, that is, the angle θ.

Next, the piezoelectric elements 52 and 53 are displaced by the same amount in the same direction, and the piezoelectric element 51 is displaced by the same amount in the opposite direction to the piezoelectric elements 52 and 53 to adjust the position of the substrate in the Y-axis direction.

Further, the piezoelectric elements 54 and 55 are displaced and brought into contact with the substrate 1, and when they hit, the piezoelectric elements 54 and 55 are moved by the same amount in opposite directions to adjust the position of the substrate in the X direction.

While making these adjustments, Mac 21-2 is
Monitor the position 4, and finish the adjustment when the mark and the microscope cursor overlap.

Effect> According to the present invention, since the substrate is positioned using a piezoelectric element capable of minute displacement, highly accurate positioning is possible. Moreover, since positioning is performed for the position of the substrate in the X-axis direction, the position in the Y-axis direction, and the inclination, precise positioning is possible. Furthermore, since the piezoelectric element itself is small, the device becomes compact.

In an optical encoder, the size of the slit formed in the code plate is small, and the PDA board is required to be positioned with high precision, so the method according to the present invention is particularly effective for such applications. be.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an example of the configuration of an apparatus for implementing the present invention, and FIG. 2 is an explanatory diagram of the operation of the apparatus shown in FIG. 1... Board, 2... PDA, 3... Fixing member, 4
...Fixing tool, 51-55...Piezoelectric element. \Me/ ×

Claims (1)

[Claims] In a substrate positioning method for positioning a rectangular substrate at a target position, a piezoelectric element that is displaced in proportion to an applied voltage is brought into contact with each side of the rectangular substrate; A first piezoelectric element is arranged on one side of a pair of sides facing each other, and second and third piezoelectric elements are arranged on the other side; A substrate positioning method in which a fourth piezoelectric element is placed on the other side, a fifth piezoelectric element is placed on the other side, and the substrate is positioned in the next step. (1) A step of adjusting the inclination of the substrate by displacing the second piezoelectric element and the third piezoelectric element in opposite directions without displacing the first piezoelectric element. (2) Displace the second piezoelectric element and the third piezoelectric element by the same amount in the same direction, and displace the first piezoelectric element by the same amount in the opposite direction with respect to the second piezoelectric element and the third piezoelectric element. A process of adjusting the position of the substrate in the Y-axis direction by displacing it. (3) A step of adjusting the position of the substrate in the X-axis direction by displacing the fourth piezoelectric element and the fifth piezoelectric element by the same amount in opposite directions.