JPH06143108A - Groove processing method and device - Google Patents

Abstract

PURPOSE:To improve diametral accuracy of a tool by decreasing the oscillation of a groove processing fine tool. CONSTITUTION:In a method and a device for mechanically forming a fine groove on a base plate 5 by a rotated fine tool 3, the groove-processing is performed on a base plate without removing the fine tool 3 from the device after correcting diametral and oscillation accuracy of the fine tool 3 by a correcting tool 4 incorporated in the device in such a state that the fine tool 3 for the purpose of processing is attached to a tool chuck 2. Thereby the oscillation of the fine tool 3 can be decreased, the diametral accuracy can be improved, moreover highly accurate groove having an optional shape can be formed on the optical material base plate 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and a processing apparatus for processing precision fine grooves on an optical material substrate.

[0002]

2. Description of the Related Art Optical devices such as optical switches and optical switches are formed on an optical material substrate such as lithium niobate, and devices on the same substrate are optical waveguides formed on the surface layer of the optical material substrate. Connected. On the other hand, in order to connect with devices on other boards or optical fibers,
It is necessary to join the end portion of the waveguide guided to the end surface of the optical material substrate and the optical fiber by aligning the optical axes of both with the micron unit.

Conventionally, the optical axes of the waveguide end and the optical fiber have been aligned and fixed one by one using a microscope. Further, a groove is processed on the substrate, and an optical fiber is installed in the groove.

[0004]

As a method of forming the groove, a method of processing the optical material substrate by etching or the like, or a method of adhering a silicon single crystal plate in which the groove is formed by anisotropic etching or the like on the optical substrate A method of forming a groove by mechanical removal processing has been considered.

However, in the case of processing by etching, for example, it is necessary to form a groove having a depth of about half the diameter of the optical fiber, and in the case of an ordinary optical communication fiber, a depth of 60 μm or more is required. It is difficult to form a groove with a micron-accuracy width and depth accuracy required for a groove of such dimensions.

In the method of forming a groove on a silicon substrate, a submicron-precision groove can be formed by using a lithography technique for semiconductor elements and anisotropic etching. It is necessary to perform alignment at the time of bonding, and it is necessary to solve the problem of a step on the surface caused by bonding the silicon substrate to the optical material substrate. As a general groove forming method, mechanical removal processing using an outer peripheral portion of a thin blade disk-shaped tool is often used, but it is suitable for forming a linear groove from end to end of the substrate, There is a drawback that it is impossible to form a groove halfway or to form a groove having an arbitrary curved shape.

A method is conceivable in which a fine cylindrical tool is processed in an end mill system while rotating about a shaft perpendicular to the surface of the workpiece. For example, when forming a fine precision groove for fixing an optical fiber, the diameter of the tool used for processing is almost equal to a desired groove width (for example, a groove for fixing an optical fiber having a diameter of 125 μm has a diameter of 125 μm).
It is necessary that the diameter accuracy and rotational runout be within the specified values.

However, the diameter of the tool may be machined to an accuracy of 1 μm or less at the time of manufacture, but an attachment error occurs when the tool is held at the tip of a rotating mechanism such as a spindle, and the diameter is several μm to several tens of μm. Since rotational runout occurs, this is a cause of deterioration in groove shape accuracy.

An object of the present invention is to solve the above-mentioned drawbacks of the prior art and to provide a groove processing method and a groove processing apparatus for mechanically processing a highly precise groove of a desired shape on a substrate.

[0010]

In order to achieve the above object, a groove machining method according to the present invention is a groove machining method having a tool shaping step and a groove machining step. Prior to the above, a cylindrical fine tool having a diameter slightly larger than the required dimension is attached to the rotating mechanism for groove machining, and the correcting tool is pressed against the rotating fine tool to
It is a machine tool that is coaxial with the rotation axis of the rotating mechanism and has a diameter of the required dimension.In the groove machining process, the machined fine tool remains attached to the rotating mechanism for groove machining, and this is placed on the substrate surface. The groove is formed on the surface of the substrate by bringing the fine tool and the substrate into relative contact with each other.

Further, the groove machining apparatus according to the present invention has a spindle mechanism, a correction tool, a measuring instrument, a moving stage mechanism, and a control mechanism, and grinds a fine tool having a diameter slightly larger than a required dimension. It is a groove processing device that takes out and shapes it into a tool shape of the required size, and performs groove processing on the substrate surface with the fine tool after shaping.The spindle mechanism shapes around the axis perpendicular to the groove processing surface of the substrate. It rotates the front and rear cylindrical fine tools, the correction tool cuts out the cylindrical fine tool on the spindle mechanism in the radial direction and the axial direction, and the measuring instrument cuts by the correction tool. The moving stage mechanism regulates the relative position between the fine tool and the substrate and the relative position between the fine tool and the correction tool, and the control mechanism. Is It is intended to control the movement stage mechanism based on the data of the fine tool shape from the measuring instrument.

[0012]

With the machining fine tool 3 still attached to the tool chuck 2, the diameter and runout accuracy of the fine tool 3 are corrected by the correction tool 4, and then the fine tool 3 is removed without removing it from the apparatus. Groove the substrate.

[0013]

The present invention will be described in detail with reference to the drawings.

FIG. 1 is a conceptual diagram for explaining the groove processing method of the present invention. In FIG. 1, reference numeral 1 is a high-precision high-frequency spindle capable of high-speed rotation. A cylindrical fine tool 3 (for example, a metal bond grindstone containing fine diamond abrasive grains) is held by a tool chuck 2 at the tip of the rotary shaft of the high-frequency spindle 1.

Reference numeral 4 denotes, for example, a conical diamond correction tool, which can be precisely moved in the axial direction and the radial direction of the fine tool 3 by being fixed on a stage (not shown).

Prior to grooving, a fine tool 3 having a diameter slightly larger than a required dimension is fixed to the tool chuck 2, and a correction tool 4 is brought into contact with and moved while rotating the high frequency spindle 1, whereby the fine tool 3 is moved. Is processed and the mounting error and bending are corrected as shown by the dotted line so that the center of rotation of the spindle coincides with the center and a tool shape equal to the required dimension is obtained.

FIG. 2 is a front view for explaining the structure of the groove processing apparatus of the present invention. In FIG. 2, 1 is a high frequency spindle, 2 is a tool chuck, 3 is a fine tool, and 4 is a correction tool. A substrate 5 is movably held on a base 6 by a horizontal stage 7 and a vertical stage 8. The correction tool 4 has a structure that is held and movable by a horizontal stage 7 and a vertical stage 8.

Reference numeral 9 denotes a non-contact type measuring device (for example, a laser type outer diameter measuring device manufactured by KEYENCE CORPORATION) held by the stages 7 and 8 to measure the outer diameter and deflection of the fine tool 3. The data of the diameter of the fine tool 3 measured by the measuring device is
Data is recorded in the recording control device 10 such as a personal computer, and the horizontal stage 7 and the vertical stage 8 are controlled using the data recorded in the recording control device 10 to process the fine tool 3 having a required size.

In this embodiment, a fine tool of a bronze type metal void diamond grindstone having a diameter of 150 ± 1 μm is attached to a spindle by a chuck (the deviation of the fine tool after attachment is 10 μm), and the diameter is measured by a measuring instrument having a resolution of 0.1 μm. The shake was measured, and based on the measured value, a fine tool was processed using a conical (vertical angle 90 degrees, tip diameter 0.1 μm) single-crystal diamond correction tool. A personal computer was used as a data recording and control device. As a result, a fine tool can be processed over a range of 100 μm in length with a diameter of 125 ± 0.5 μm and a maximum deflection of 0.5 μm. With this tool, a width of 125 μm and a depth of 63 μm can be formed on a lithium niobate substrate. It was possible to form the groove of (1) in an arbitrary shape with an accuracy of ± 1 μm.

In this embodiment, the horizontal movement mechanism is uniaxial for simplification of description, but by providing the movement mechanism in a direction perpendicular to this, a groove of arbitrary shape can be formed. Needless to say. Further, the case where a single stone diamond is used as the correction tool 4 is shown, but the same effect can be obtained by using a multi-stone stone, a grindstone, or a rotary correction tool.

In this embodiment, the substrate, the correction tool, and the measuring instrument are installed on the same stage. However, even if they are installed on another stage or detachable, It goes without saying that the same effect can be obtained. Further, by applying the main processing to the processing of the end surface portion of the fine tool, the end surface portion can be processed into an arbitrary shape, and the groove shape such as the semicircular cross section or the triangular cross section can be easily processed.

[0022]

As described above, when the groove processing method and the groove processing apparatus of the present invention are used, it is possible to form a groove having an arbitrary shape with high precision on a substrate, which is very useful as a method for processing an optical material substrate. It is valid.

[Brief description of drawings]

FIG. 1 is a conceptual diagram for explaining a groove processing method of the present invention.

FIG. 2 is a front view for explaining the structure of the groove processing method and the groove processing apparatus of the present invention.

[Explanation of symbols]

 1 high frequency spindle 2 tool chuck 3 micro tool 4 correction tool 5 substrate 6 base 7 horizontal stage 8 vertical stage 9 measuring instrument 10 recording controller

Claims (2)

[Claims] 1. A grooving method having a tool shaping step and a grooving step, wherein the tool shaping step is for grooving a cylindrical fine tool having a diameter slightly larger than a required dimension prior to grooving. It is attached to the rotating mechanism of, and the correction tool is pressed against the rotating fine tool, and the fine tool is cut into a tool shape coaxial with the rotation axis of the rotating mechanism and having a diameter of the required dimension. Is characterized in that the machined fine tool is still attached to the groove rotation mechanism and is brought into contact with the substrate surface, and the fine tool and the substrate are moved relative to each other to form the groove on the substrate surface. Groove processing method. 2. A spindle mechanism, a correction tool, a measuring instrument, a moving stage mechanism, and a control mechanism, and a fine tool having a diameter slightly larger than the required dimension is machined to obtain a tool shape of the required dimension. A grooving device for shaping and grooving the surface of a substrate with a fine tool after shaping. A spindle mechanism rotates a cylindrical fine tool before and after shaping around an axis perpendicular to the grooved surface of the substrate. The correction tool is used to machine the cylindrical fine tool on the spindle mechanism in the radial and axial directions, and the measuring instrument is to measure the cylindrical fine tool that is being machined by the correction tool. The diameter and deflection are measured, the moving stage mechanism regulates the relative position between the micro tool and the substrate, and the relative position between the micro tool and the correction tool.The control mechanism controls the micro tool shape from the measuring instrument. of Grooving apparatus, characterized in that to control the movement stage mechanism based on the over data.