JPH0584659A - Position adjusting method for polished member - Google Patents

Abstract

PURPOSE:To provide an adjusting method whereby no position displacement is generated even when frictional external force is applied to act, in the position adjusting method for a polished member. CONSTITUTION:In a sample table in which a position of a polished member 6 can be adjusted by action of rotational feeding a screw 5, by removing a twist amount of the screw accumulated in an adjusting process, no position displacement is generated even when external force acts at the time of polishing. Since polishing work is performed after eliminating residual stress provided in an adjusting mechanism, the high accurate polishing work can be realized with no position displacement of the polished member.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for adjusting the position of an object to be polished on a sample table in a polishing machine such as a lapping machine.

[0002]

2. Description of the Related Art A technique of this kind is disclosed in JP-A-57-57.
It is disclosed in Japanese Patent Publication No. 96767.

In this technique, a thin plate-shaped member to be polished is pressed and bonded to a substrate coated with an adhesive, and then processed by a polishing device.

[0004]

According to this known technique, it is easy to grind the top surface of an object to be polished having a uniform bottom thickness and a top surface parallel to the bottom surface. is there.

However, it is unsuitable for polishing the top surface of the object to be polished whose bottom surface and top surface are not parallel.

Furthermore, the object to be polished is a layered member, and it is not easy to polish the intermediate layer, not the surface layer, of the layered member.

In particular, it is impossible to polish the polishing target layer if the polishing target layer is not parallel to the bottom surface. Here, there is a case where the layer which is the polishing target is not parallel to the bottom surface, but the shape of the polishing object alone may be intentionally changed to such a shape. Therefore, in many cases, they are not parallel to each other, and further, the polishing target layer is inclined due to variations in the thickness of the adhesive layer when the object to be polished is bonded to the substrate.

Therefore, according to the conventional technique, it is impossible to perform accurate polishing along the polishing target layer. In particular, in recent years, with the demand for higher precision, it is often necessary to carry out polishing with a precision on the order of submicrons, and in such a case, the conventional technique cannot cope.

An object of the present invention is to provide a polishing target layer easily and highly accurately even if the object to be polished is a member having a layered structure and a specific polishing target layer therein is not parallel to the bottom surface. It is an object of the present invention to provide a method for adjusting a position of a member to be polished, which does not shift the position of the member to be polished, especially in the case of a sample table having a structure in which the position of the member to be polished can be adjusted.

[0010]

In order to achieve the above object, the basic principle of the sample table according to the present invention will be outlined.

That is, the object to be polished is not directly bonded to the sample table having a fixed structure as in the conventional case, but the sample table is roughly divided into a fixed portion and a movable portion, and the movable portion is movable with respect to the fixed portion. The part has a structure that can be adjusted and fixed in both the vertical direction and the tilting direction, and the member to be polished is bonded to the movable part.

Based on this principle, the basic policy for embodying the method of adjusting the position of the sample table and the member to be polished mounted thereon is defined as follows.

A structure and a position adjusting method capable of adjusting a member to be polished in a vertical direction and a tilting direction with high precision and preventing displacement of the member to be polished after adjustment even when an external force for polishing acts. thing.

As a concrete structure based on this principle and principle, the present invention is a polishing apparatus having a structure for performing polishing by mounting a sample table to which a member to be polished is attached. The sample table is fixed plate and movable plate. The two members are connected and fixed at one end, the driving member is inserted into the gap between the side faces of the other end, and the driving member is rotated by the screw feed operation provided at this location. By putting in and out, the wedge principle is applied to elastically deform the movable plate like a cantilever, and the structure is such that the position of the abraded member adhered to the flat surface of the movable plate is adjusted, and Two pairs of screws and drive members are arranged at right angles to the tilt direction of the movable plate, and the heights of the members to be polished are adjusted by making the insertion amounts of the two drive members different. , It is also possible to adjust the tilt. In, by rotating the screw, after adjusting the position of the member to be abraded to the target position, by reversing the screw by a minute amount by the amount of twist of the screw generated and stored during the screw feeding operation, An adjustment method was adopted in which the member to be polished set on the sample stage was not displaced even if an external processing force was applied during polishing. (That is, before processing,
If the twisting amount of the screw accumulated during the screw feeding operation is not released and eliminated beforehand, the twisting will return to the original amount by a random amount due to the external force or vibration during processing. Tilts and cannot be ground correctly. In practicing the present invention, it is desirable to arrange the fixed plate and the movable plate along the circumference.

[0015]

According to the above configuration and position adjusting method, the member to be polished is not directly fixed (eg, adhered) to the sample table, but the member to be polished is fixed (eg, adhered) to the movable plate. The movable plate is attached to the fixed plate, and the movable plate, to which the member to be ground is fixed, is adjusted to the fixed plate both in the height direction and the inclination direction by two driving members. However, it is possible to position the member to be polished, and after positioning, even if external force is applied to the member to be polished, the amount of twist of the adjusting screw is removed beforehand, so the position of the member to be polished will not be displaced. Can be prevented.

For this reason, the height and inclination of the surface to be polished can be adjusted for each member to be polished fixed to each movable plate, and the target layer to be polished is parallel to the bottom surface of the sample table. It can be ground with extremely high precision.

[0017]

EXAMPLE A method for adjusting the position of a member to be polished according to the present invention is shown in FIG.
High precision polishing is realized on the sample stand shown in (1).

First, the basic structure of the sample table will be described with reference to FIG.

A sample table 1 comprises a fixed plate 2, a movable plate 3, a driving taper pin 4, a feed screw 5 and the like. A large number of members to be polished 6 are attached to the upper surface of the movable plate 3 to adjust the position. After that, the sample table 1 is mounted on a polishing device (not shown) and polishing is performed.

The sample table 1 is in the shape of a disk, and the movable plate 3 is fixed to the fixed plate 2 and the set screw 7 is provided at the center thereof.
It is concluded with. The movable plate is divided into 16 parts by 16 notches 8 in the circumferential direction from the central part. However, each of the divided elements 3'and 3 "is connected at the central portion to form an integral structural component. The abraded member 6 is provided with a wax 9 on the flat end portion of each of the divided elements 3'and 3". It is attached.

The outer peripheral portions of the fixed plate 2 and the movable plate 3 are tapered as shown in FIG. 2 which is a partial sectional view of FIG. In this tapered portion, two taper pins 4 are assembled to the fixed plate 2 by screws 5 for each of the dividing elements 3 ′ and 3 ″. Further, the through holes 4 a of the taper pins 4 are different from the screws 5. It has a ridiculous hole size.

The distance between the fixed plate 2 and the tapered portion of the movable plate 3 is set to be small depending on the outer diameter of the tapered pin 4. Here, the plate thickness of the movable plate 3 is made thin enough to be elastically bent, while the plate thickness of the fixed plate 2 is made thick so that the bending can be ignored. For this reason, when the screw 5 is rotated to move the taper pin 4 forward and backward, the tip of the movable plate 3 is elastically displaced by the wedge principle, and the split elements 3'and 3 "are arranged. By making the amount of advance and retreat of the two taper pins different, the position of the member to be polished 6 is not limited to the vertical direction,
It can also be adjusted in the tilt direction.

Here, the rotating operation of the screw 5 is performed by engaging the bit 16 with the head of the screw 5 in FIG. 2 and rotating the bit 16 by a drive unit (not shown). In order to adjust the position of the member to be polished 6 with an accuracy of micron order, the screw 5, the rattle 5a of the screw hole portion and the rattling of the bit driving unit need to be offset, and the screw should be pushed in the direction of pushing the taper pin 4. It rotates in one direction and moves the movable plate 3 gradually.

When the polished member 6 reaches a predetermined height, the bit 16 is removed from the head of the screw 5.

Next, in the sample stage having this structure, a method for adjusting the position of the member to be polished set on the sample stage will not be displaced during polishing, even if an external processing force acts, will be described.

Generally, when the position of an object is adjusted by an adjusting mechanism, if the internal force remains in the mechanism at the end of the adjustment, the internal force is partially released during processing, and it is seen in micron order. In the case, the position of the object is displaced.

In FIGS. 2 and 3, the screw 5 is rotated and fed at the time of adjustment to move the movable plate 3 through the taper pin 4 to position the member 6 to be polished at the target position. At this point, when the positioning of the screw 5 is completed, the state of the screw 5 will be described in detail. As shown in FIG.
Torsional elastic deformation θ is generated by the screw driving torque T at the time of adjustment, and this state is maintained via the taper pin 4 by the deformation reaction force of the movable plate 3. That is,
The screw residual stress P is inherent. In this state, when the member 6 to be polished is ground, the force transmission of the boundary portion 4'between the taper pin 4 and the movable plate 3 and the lower surface of the screw head 5'and the end surface of the taper pin 4 5'because of external processing force and vibration. However, unlike the situation at the time of positioning, the screws may be separated momentarily at the boundary 4'and the end face 5 "when the external machining force / vibration is excessive. , Tries to return to its original, untwisted state, a random amount. Then, corresponding to this returned amount, the taper pin 4
The position of the movable plate 3 is also displaced via the. Moreover, FIG.
Therefore, the returning amounts of the pair of left and right screws 5 are not necessarily the same, and therefore, as shown in FIG.
Is tilted and cannot be ground properly.

Therefore, in the present invention, in the final stage of adjusting the position of the member to be polished 6, the pair of left and right screws 5 shown in FIG. 3 are slightly inverted by the amount of the twist of the screws generated during the adjustment to finish the adjustment. And

Here, the twist amount θ is obtained as follows.

In FIGS. 5 and 6, θ is represented by the following equation based on the mechanical balance relationship.

[0031]

[Equation 1]

However, T: screw drive torque, G: lateral elastic modulus of screw, l: length of straight portion, d: effective diameter of screw, where T is represented by the following formula from the force relationship of the screw portion. It

[0033]

[Equation 2]

However, F: axial force acting on the screw, d: effective diameter of the screw, β: lead angle of the screw, μ ₂ : friction coefficient between threads, where F acts from the movable plate 3 in FIG. It is expressed by the following equation from the balance of force with the force Q to be applied.

[0035]

[Equation 3]

However, Q: force acting from the movable plate,
μ ₁ : Friction coefficient of the boundary portion 4 ′ between the movable plate and the taper pin, α: Angle of the tapered portion Here, Q is shown in the following formula because the movable plate 3 in FIG. 6 can be regarded as a cantilever beam.

[0037]

[Equation 4]

However, b, h, and c: geometrical dimension of beam, E: elastic modulus of beam, Z: amount of deformation of beam Since each constant of each of these equations is known, equation (1)
The twist amount θ is determined more.

As described above, by removing the torsional deformation amount θ of the screw when the position adjustment of the member to be polished is completed, the member to be polished may be displaced even if an external processing force is applied during polishing. Absent.

According to this embodiment, the position of the member 6 to be polished can be adjusted, and the polishing process with extremely high precision can be realized.

Now, as shown in FIG. 7, it is assumed that the polishing target layer 6a of the member 6 to be polished has an angle γ with respect to the bottom surface 6b. In such a case, the movable plate 3 is inclined counterclockwise in the figure by an angle γ and its top surface is inclined as indicated by 3a (shown by a virtual line). As a result, the polishing target 6a becomes horizontal.

According to this embodiment, even if the member to be polished is a layered product and the position and inclination of the target polishing layer are indefinite, polishing along the target polishing layer is easy and highly accurate. Can be done at. That is, it is possible to accurately position the member to be polished attached to the sample table in the vertical direction and the tilt direction, and the position of the member to be polished after adjustment does not shift at all even when external force for polishing acts. Therefore, polishing can be performed with extremely high accuracy (accuracy of submicron order).

[0043]

According to the present invention, since the mounting position and the mounting posture of the member to be polished can be regulated easily and with high accuracy, the polishing target surface of the member to be polished is not uniform. Or, even if the adhesion error of the member to be polished is large, it is possible to absorb these variations and correct it to a predetermined height in a predetermined direction (generally horizontal) quickly and easily. Since the residual stress of the position adjusting mechanism is removed, even if an external polishing force is applied, the position of the member to be polished does not shift, and highly accurate polishing can be performed.

[Brief description of drawings]

FIG. 1 is a perspective view of an embodiment of the present invention,

2 is a cross-sectional view of the main part of FIG.

FIG. 3 is a front view of the main part of FIG.

FIG. 4 is an explanatory view showing a displacement of a member to be polished during polishing by a conventional position adjusting method,

FIG. 5 is an explanatory view of a screw straight portion,

FIG. 6 is an explanatory view of a force relationship of a screw part of the present invention,

FIG. 7 is an explanatory diagram of an operation method and effects of this embodiment.

[Explanation of Codes] 1 ... Sample stage, 3 ... movable plate, 4 ... taper pin, 5 ...
Screw, 6 ... Member to be polished.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shigeki Yamamura 1410 Inada, Katsuta City, Ibaraki Pref., Inside the Tokai Plant, Hiritsu Manufacturing Co., Ltd.

Claims (1)

[Claims] 1. A polishing apparatus having a structure for mounting a sample table to which a member to be polished is attached, wherein the sample table is divided into a fixed part and a movable part, which are connected and fixed at one end and the other end. The side surface is tapered, the driving member is inserted into the tapered portion, and the driving member is moved by the rotary feed operation of the screw provided at that portion, so that the principle of the wedge is applied to move the movable portion. The structure is such that it is elastically deformed like a cantilever to adjust the position of the abraded member adhered to the plane part of the movable part, and the screw and the driving member are arranged in the tilt direction of the movable part. Two pairs are arranged at right angles to
The insertion amount of each of the two driving members was appropriately set, and the movable portion was elastically bent and deformed so that not only the height of the abraded member but also the inclination could be adjusted. In the mechanism, the screw is rotated and fed, the member to be polished is positioned at a target position, and then the screw is inverted by a minute amount by the amount of twist deformation of the screw generated during the screw feeding operation. Position adjustment method for the member to be polished.