JPH03170265A - Constant-size polishing method and device and work fixing plate - Google Patents

Abstract

PURPOSE:To greatly improve the flatness, parallelism and dimensional precision of a work and achieve more precise and high efficient lapping by forming a face on the opposite side of the first face into flatness as the second face, the outer periphery of which is provided with three or more measuring portions and a detecting portion to detect variation in the positions of the measuring portions. CONSTITUTION:Variation in the face position of the second face, which is set on the opposite side (or the other side) of the first face, of a work fixing plate 4 is detected by sensors 10-12 as such or in comparison with the reference portion of the work fixing plate 4 and a reference ring 6 retaining the work fixing plate 4, thereby to predict the lapping amount of a work 5 to be machined. Also, by detecting three or more face positions, the lopsided lapping condition of the machined face can be found. In addition, by detecting the face positions using a detecting portion which is formed on the second face of the work fixing plate and varied in width in sequence, positions to be detected can be recognized.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a lapping method, and more particularly to a method for lapping highly brittle materials such as ◆9 semiconductor, optical, magnetic, and electronic related materials with high precision, an apparatus thereof, and a workpiece fixing plate.

[Conventional technology] Wrapping to create a flat surface is generally done by
There are two methods: a double-sided simultaneous machining method in which the workpiece is sandwiched between the upper and lower surface plates, and a single-sided machining method in which the workpiece is processed only with the lower surface plate.However, it is possible to finish workpieces with different shapes on the front and back, extremely thin workpieces, or both surfaces. Single-sided machining is used for any workpieces that require varying surface roughness.

FIG. 4 is a perspective view showing a conventional one-sided machining method. In this figure, 41 is a polishing surface plate made of tin,
Copper, cast iron, resin, etc. are used, and narrow grooves such as spiral, concentric circles, and mesh shapes are formed on the surface. 47 is the leg,
A spindle (not shown) to which the polishing surface plate 41 is attached
It also incorporates a continuously variable speed motor (not shown) that drives the spindle via a belt (not shown).

Reference numeral 42 denotes a workpiece fixing plate, on the lower surface of which a workpiece (not shown) is adhesively fixed. A carrier arm 46 is fastened to a carrier arm support 48 fixed to the leg 47. Two rollers 44 are pivotally supported on the carrier arm 43, and serve to position the workpiece fixing plate 42 on the polishing surface plate 41 and to smoothly rotate the workpiece fixing plate 42 during processing. do. A processing liquid nozzle 49 supplies a polishing liquid onto the polishing surface plate 41 during processing.

FIG. 5 is an explanatory diagram of a conventional method for measuring the thickness of a workpiece, which is carried out before, during or after machining, and the amount of polishing is calculated from the difference. 20 is a measuring surface plate made of stone or cast iron. The top surface is processed into a highly accurate flat surface,
A gauge post 21 is vertically attached to one end. 26 is a dial gauge, which is attached to the support column 21. Further, it is attached to a gauge holder 22 that is positioned and fixed at any vertical or vertical position. The workpiece fixing plate 42 has the workpiece 5 adhesively fixed to one side thereof. During the ramping process, the workpiece fixing plate 42
is removed from the polishing machine, the workpiece 5 is placed on the measuring surface plate 20 facing upward, and the hook fixing plate 42 is placed on the measuring surface plate 20.
The height h from the workpiece adhesive surface is measured by the dial gauge 23.
Measure with.

[Problem to be solved by the invention]

However, in the conventional method described above, it is necessary to perform several measurements until a predetermined dimension is reached, which takes time. In addition, there is a concern that the sharpness may become unstable due to changes in the condition of the surface plate, resulting in defects due to over-polishing.

Currently, the accuracy and efficiency of wrapping depends on the skill and intuition of the operator.

Therefore, it is an object of the present invention to provide a sizing polishing method, a polishing device, and a workpiece fixing punch that require less time for measurement, can perform highly accurate machining, and can simultaneously measure the unbalanced polishing (uneven polishing). .

[Means to solve the problem]

In order to achieve the above object, the present invention adhesively fixes a workpiece to a first surface of a workpiece fixing plate, holds the workpiece fixing plate, and brings the workpiece into contact with a polishing surface plate, In the polishing method of polishing the workpiece by rotating this polishing surface plate, on the opposite side of the first surface of the workpiece fixing plate (
Alternatively, by detecting the change in the cylinder position of the set second surface as it is or by comparing it with the reference part of the workpiece fixing plate and the reference ring that holds this workpiece fixing plate, This is achieved by estimating the amount of polishing and processing.

Furthermore, by detecting three or more positions, the uneven polishing state of the machined surface can be determined.

Furthermore, the detection of the surface position is performed using the second part of the workpiece fixing plate.
The detected location is recognized by using a detection section formed on the surface of which the width is successively changed.

Further, the apparatus for carrying out the above method adhesively fixes the workpiece to the first surface of the workpiece fixing plate, holds the workpiece fixing plate, and brings the workpiece into contact with the polishing surface plate. , in a polishing device for polishing the workpiece by rotating the polishing surface plate, a surface opposite to the first surface is formed into a flat surface to form a second surface; This can be accomplished by providing three or more measuring sections on the outer circumference and further providing a detecting section for detecting changes in the position of the measuring sections.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

FIG. 1 is an explanatory view of an embodiment of the sizing polishing method according to the present invention, and (a) is a schematic cross-sectional view of an apparatus for carrying out the embodiment.

Reference numeral 1 denotes a polishing surface plate, which is attached to a spindle 2 and drives a pulley (not shown) and a belt (not shown) from a continuously variable speed motor (not shown) attached inside a leg (not shown). It rotates when power is transmitted through it.

A cover 6 is attached to the leg (not shown) to prevent the polishing liquid from scattering. A workpiece fixing plate 4 has a workpiece 5 fixed to its lower surface with wax. Then, the workpiece fixing plate 4 is inserted into a guide 7 made of resin or the like and attached to the inside of the reference ring 6 placed on the polishing surface plate 1, and placed on the polishing surface plate 1. It is placed there. The reference ring 6 is made of a high-density ceramic such as alumina or silicon nitride, in whole or in part (only the side of the contact surface with the polishing surface plate 1), and has wear resistance. Also, the parallelism of the upper and lower surfaces is 0. The upper end surface, which serves as the measurement surface, is kept within 5 μm and polished to a smooth mirror finish, which is used as the measurement standard for this sizing polishing process.

10 to 12 are non-contact displacement sensors with laser capacitance,
A system using a current or the like is used, and is attached to the arm 9. The arm 9 is fastened to a post 8 fixed to the leg (not shown). Further, the arm 9 and the support column 8 are made of a material with a low coefficient of thermal expansion, such as invar, in order to reduce thermal deformation.

FIG. 1(b) is an explanatory diagram of the embodiment, and is a schematic diagram seen from the top. The mounting positions of the non-contact displacement sensors 10 to 12 on the arm 9 are arranged and mounted on the sensor mounting center line A, and the sensor mounting center line A is perpendicular to the arm center line B. The arrangement is taken into consideration so that even if the support column 8 and the arm 9 collapse due to thermal deformation, measurement errors are unlikely to occur.

Reference numeral 16 denotes a carrier arm, on which a %2f roller 14 is pivotally supported, and is fastened to a carrier arm support 15 fixed to the leg (not shown). Further, the carrier arm 16 is positioned so that the reference ring 6 rotates smoothly at a fixed position on the polishing surface plate 1 during processing.

Normally, when the polishing surface plate 1 rotates in the direction of the arrow (■) in the figure, the reference ring 6 rotates in the direction of the arrow (■) in the figure due to the difference in circumferential speed, but the rotational speed is different from that of the polishing surface plate 1. It depends on the flatness, the shape and arrangement of the work 5, etc. In addition, as a means to rotate smoothly and perform uniform processing when it is difficult to rotate smoothly, the legs (not shown) are used.
Or a forced drive device attached to the carrier arm 16 (
A method of forcibly rotating the reference ring 6 via a belt (not shown) using a belt (not shown) or a method of forcibly rotating the reference ring 6 using a belt (not shown);
4 through a belt (not shown) to help rotate the reference ring 60.

16 is an abrasive grain supply nozzle that continuously or intermittently supplies abrasive grains 17 onto the polishing surface plate 1.

FIG. 2 is a schematic diagram showing the positional relationship of each sensor during measurement. P, is the measurement point on the reference ring 6 of the non-contact displacement sensor 10 (the intersection of the ring 6 with a straight line connecting P2 and P3, which will be described later), and P2 is the measurement point of the non-contact displacement sensor 1) on the reference ring 6. Measurement points P3 at the four corners of the plate 4 during rotation are the non-contact displacement sensors 1
This is the measurement point at the center of the workpiece fixing plate 4 of No. 2. Measurement surfaces a to e are provided on the upper surface of the workpiece fixing plate 4 and are located at the same height from the bottom surface, of which a to d are located at the four corners, and e is located at the center. The measurement surfaces a to d can also be formed by making the side surface connecting the upper surface and the lower surface sloped, but processing of the measured values becomes complicated. f is the work fixing plate 4
This is an imaginary circle drawn by the centers of measurement surfaces a to d at the four corners of the workpiece fixing plate 4 when the workpiece fixing plate 4 rotates. Further, the width dimensions of the measurement surfaces a to d are sequentially changed in the circumferential direction of the virtual circle f to cause a difference in the measurement output so that each measurement collapse corresponds to the measurement value. . Further, as a means for forming the measurement surfaces a to d, a coating, a film mask, etc. can be used. The shape of the work fixing plate 4 may be circular or polygonal.

FIG. 3 is a schematic diagram showing waveforms detected during processing by the non-contact displacement sensor 1). In the figure, a1 to d correspond to the measurements ayd on the workpiece fixing plate 4. H is a height dimensional deviation, which approximately represents the parallelism of the workpiece 5, and changes depending on the amount of uneven wear that occurs during processing.

In this way, the amount of uneven wear and the uneven polishing position can be confirmed without contact, so from the information obtained, it is possible to improve parallelism by using an uneven load method, etc. that applies a load to the part to be machined.

Furthermore, since the non-contact displacement sensor 12 measures the center of the workpiece fixing plate 4 at the same time, the amount of polishing at the center of the workpiece and the overall parallelism can be known at the same time. However, even if the positional relationship between the sensor support system and the polishing surface plate 1 changes due to thermal displacement during processing, and the absolute dimensions change, the information from the non-contact displacement sensors 1) and 12 The abnormality cannot be detected and becomes a machining dimensional error. In order to prevent this, the upper surface of the reference ring 6 is simultaneously measured using the non-contact displacement sensor 10 attached to the same support system as the non-contact displacement sensors 1) and 12, and the non-contact displacement sensor 12 is measured. By comparing the values, even if an absolute value deviation occurs due to a change in the support system, etc., it is possible to make the machining dimensional error extremely small. Also, the amount of wear during processing of the reference ring 6 is overwhelmingly smaller than the amount of polishing of the workpiece 5, so it can be almost ignored in normal polishing, but when dimensional control on the submicron order is required, the amount of wear is much smaller than the amount of polishing of the workpiece 5. This is achieved by making corrections.

By setting the machining amount from the outputs of the non-contact displacement sensors 10 and 12, and by using means for automatically stopping the machine when the set value is reached, highly accurate sizing machining can be performed. For example, the workpiece is made of ferrite material, the polishing surface plate 1 is made of tin, and the non-contact displacement sensors 10-
Table 1 shows the data obtained when lapping was actually performed to a fixed size using a laser displacement meter as the abrasive grain 12, using diamond powder as the abrasive grain 17, and correcting the wear amount of the reference ring 60.

As shown in the table above, both the sizing accuracy and the amount of uneven polishing under the two conditions were improved to 1/3 or less compared to the conventional method.

〔Effect of the invention〕

Since the present invention uses a non-contact displacement sensor as a means for measuring the amount of polishing during lapping, it does not require measurement time and can be measured continuously and with high precision, while also eliminating errors between operators. There is no need to worry about this, and the occurrence of defects due to workpiece handling errors that often occur during measurement work is also eliminated. In addition, by measuring and monitoring each point using multiple sensors, the flatness, parallelism, and dimensional accuracy of the workpiece are greatly improved compared to conventional methods.At the same time, automatic sizing is possible, resulting in high precision wrapping. It has a great effect on efficiency and efficiency.

4 Brief Description of the Drawings Fig. 1 is an explanatory drawing showing an embodiment of the present invention, in which (a) is a schematic cross-sectional view showing the device, (b) is a schematic top view of the device, and Fig. 2 is a measurement 3 is a schematic diagram showing the positional relationship of each sensor at the time, FIG. 3 is a schematic diagram of a detection waveform by a non-contact displacement sensor, FIGS. 4 and 5 show a conventional example, and FIG. 4 is a perspective view of the device, FIG. 5 is an explanatory diagram of the measurement method.

1, 41... Polishing surface plate, 4... Work fixing plate, 5... Work, 6... Reference ring, 7... Guide, 10-12...Non-contact displacement sensor 13, 43
...Carrier arm, 14, 44...
Roller Figure 2 Figure 4

Claims (8)

[Claims] (1) By adhesively fixing a workpiece to the first surface of a workpiece fixing plate, holding this workpiece fixing plate, and bringing the workpiece into contact with a polishing surface plate, and rotating this polishing surface plate. , in the polishing method for polishing the workpiece, the polishing amount of the workpiece is estimated and processed by detecting a change in the surface position of the second surface of the workpiece fixing plate. A fixed size polishing method. (2) The sizing polishing method according to claim 1, wherein the second surface is a surface opposite to the surface to which the workpiece is adhesively fixed. (3) The sizing according to claim 1 or 2, wherein the change in the surface position of the second surface of the workpiece fixing plate is detected by comparing it with a reference portion formed at the center of the workpiece fixing plate. Polishing method. (4) A workpiece fixing plate is held by a supported reference ring, and a change in the surface position of the second surface of the workpiece fixing plate is detected by comparing it with the reference ring. The sizing polishing method described in 2. (5) The sizing polishing method according to claim 1 or 2, characterized in that changes in the surface position of the second surface of the workpiece fixing plate are detected at three or more locations. (6) Detection of changes in surface position at three or more locations on the second surface of the workpiece fixing plate is performed at the second surface of the workpiece fixing plate.
6. The sizing polishing method according to claim 5, characterized in that the method is carried out using a detecting portion formed on the surface of which the width is successively changed. (7) a workpiece fixing plate forming a first surface;
a polishing surface plate, the workpiece is adhesively fixed to the first surface of the workpiece fixing plate, the workpiece is held in contact with the polishing surface plate, and the workpiece is brought into contact with the polishing surface plate; In a polishing device that polishes the workpiece by rotating a surface plate, a surface opposite to the first surface is formed into a flat surface as a second surface, and an outer circumferential portion of the second surface is formed. A polishing apparatus comprising three or more measuring parts, and further comprising a detecting part for detecting a change in the position of the measuring parts. (8) A member for adhesively fixing a workpiece to a first surface and polishing the workpiece by pressing it against a rotating polishing surface plate, the surface opposite to the first surface being formed into a flat surface. A workpiece fixing plate, characterized in that the plate has a second surface and three or more measurement parts are provided on the outer periphery of the second surface.