JP7111562B2 - Processing method - Google Patents

Description

TECHNICAL FIELD The present invention relates to a processing method for cutting a dome-shaped workpiece having a recessed portion inside.

Infrared lenses, which are used in medical equipment and can transmit infrared rays to observe subjects, are made from crystalline materials such as zinc selenide (ZnSe), zinc sulfide (ZnS), germanium (Ge), and silicon (Si). manufactured (see, for example, Patent Document 1).

The performance of the infrared lens as described above is affected by the state of the crystal structure of the material, and because it must be processed with high precision in order to exhibit its performance as an infrared lens, the infrared lens is cut with a cutting blade. In some cases, the crystal structure and dimensional accuracy are confirmed.

Japanese Patent Application Laid-Open No. 2000-075203

As described above, the infrared lens is composed of so-called brittle materials such as zinc selenide (ZnSe), zinc sulfide (ZnS), germanium (Ge), and silicon (Si). When trying to cut a dome-shaped workpiece having a dent on the inside with a cutting blade, microvibrations due to the cavity of the inner dent occur, and unintended chipping occurs on the cut surface, resulting in poor dimensional accuracy. Alternatively, there is a problem that confirmation of the crystal structure is hindered.

The present invention has been made in view of the above facts, and a main technical problem thereof is to provide a processing method for cutting a dome-shaped workpiece made of a brittle material and having a recess inside.

In order to solve the above main technical problems, according to the present invention, there is provided a processing method for cutting a dome-shaped workpiece made of a brittle material and having a recessed portion on the inside thereof with a cutting blade, wherein the recessed portion is made of polyolefin a sheet thermo-compression bonding step of laying a polyester-based or polyester-based sheet and heating and crimping the sheet; At least a cutting step of holding the solidified liquid resin embedded in the workpiece on a chuck table and cutting the workpiece with a cutting blade, and a removing step of removing the liquid resin solidified together with the sheet , In the sheet thermocompression bonding step, the sheet cut into a substantially isosceles triangular shape is prepared, the vertex of the substantially isosceles triangular sheet is positioned at the center of the inside of the dome shape, and the entire inside of the dome shape is covered. A processing method is provided for laying and arranging like umbrella sticking . Further, according to the present invention, there is provided a processing method for cutting a dome-shaped workpiece made of a brittle material and having a recessed portion on the inside thereof with a cutting blade, wherein the recessed portion is filled with a polyolefin-based or polyester-based sheet. A sheet thermocompression bonding step of laying the sheet, heating and crimping the sheet, a resin burying step of burying and solidifying a liquid resin in the recesses formed by the thermocompression bonded sheet, and embedding and solidifying in the workpiece. The dome-shaped workpiece comprises at least a cutting step of holding the liquid resin side of the sheet on a chuck table and cutting the workpiece with a cutting blade, and a removing step of removing the liquid resin solidified together with the sheet. The brittle material constituting the is silicon, a through hole is formed in the center, and in the cutting process, the thickness of the cutting blade is smaller than the diameter of the through hole, and the processing method for halving the through hole is provided.

In the former machining method, the brittle material constituting the dome-shaped workpiece is silicon, and a through hole is formed in the center. is also small and can bisect the through-hole. Furthermore, in the resin embedding step, the liquid resin is a liquid resin that is solidified by irradiation with ultraviolet rays, and it is preferable to embed the liquid resin in multiple steps.

The processing method of the present invention is a processing method in which a dome-shaped workpiece made of a brittle material and having a recessed portion inside is cut with a cutting blade, and a polyolefin or polyester sheet is laid in the recessed portion. a sheet thermocompression bonding step of heating and crimping the sheet; a resin burying step of burying and solidifying a liquid resin in the depressions formed by the thermocompression bonded sheet; The step of holding the liquid resin side on a chuck table and cutting the dome-shaped work piece with a cutting blade, and the removing step of removing the liquid resin solidified together with the sheet. The sheet cut into a substantially isosceles triangular shape is prepared, the apex of the substantially isosceles triangular sheet is positioned at the center of the inside of the dome shape, and the sheet is spread over the entire inside of the dome shape like an umbrella. A processing method for cutting a dome-shaped work piece made of a brittle material and having a recess on the inside with a cutting blade, wherein a polyolefin or polyester sheet is laid in the recess a sheet thermocompression bonding step of heating and compressing the sheet; a resin embedding step of embedding and solidifying a liquid resin in the depressions formed by the thermocompression bonded sheet; The dome-shaped workpiece is composed of at least a cutting step of holding the resin side on a chuck table and cutting the workpiece with a cutting blade, and a removing step of removing the liquid resin solidified together with the sheet. The brittle material to be processed is silicon, and a through hole is formed in the center. When cutting an object, there is no cavity in the dome-shaped recess of the workpiece, microvibration caused by the cavity is suppressed, chipping on the cut surface is prevented, and dimensional accuracy after cutting is improved. and the crystal structure can be well confirmed. In addition, a polyolefin or polyester sheet that does not require an adhesive layer is laid, and the sheet is heated and crimped to cover the recessed part inside the workpiece, so that the recessed part of the workpiece is covered. When the embedded resin is removed, no residue is left on the workpiece when the sheet is peeled off.

1 is an overall perspective view of an infrared lens to be processed in this embodiment, and a cross-sectional view taken along line AA. FIG. 1. It is a perspective view which shows the aspect which implements a sheet|seat thermo-compression-bonding process with respect to the to-be-processed object shown in FIG. 3(a) is a perspective view showing a mode when a resin embedding step is performed on the workpiece shown in FIG. 2, and (b) is a BB cross-sectional view of the workpiece shown in (a). FIG. 4 is a perspective view showing a manner in which the workpiece shown in FIG. 3 is held on a frame via a dicing tape; 1 is an overall perspective view of a cutting device for bisecting a workpiece; FIG. FIG. 4 is a perspective view showing a mode of performing a cutting step for halving a workpiece; (a) An end view showing one cut surface of a halved workpiece, (b) an end view showing a mode of removing a sheet and resin from the halved workpiece.

Hereinafter, an embodiment related to a processing method configured based on the present invention will be described in more detail with reference to the accompanying drawings.

FIG. 1 shows a perspective view and an AA section of an infrared lens 10 made of silicon (Si), which is a workpiece in this embodiment. As shown in the figure, the infrared lens 10 has a dome shape having a convex shape on the front surface 10a side and a concave portion 10d on the back surface 10b side, that is, inside, and a through hole 10c is formed in the center. It is The infrared lens 10 prepared in this embodiment has a diameter of 60 mm, a thickness of 5 mm, a height of 12 mm, and a diameter of the through hole 10c of 2.5 mm.

After preparing the above-described infrared lens 10, first, a sheet is laid in the concave portion 10d on the back surface 10b side of the infrared lens 10, and a sheet thermocompression bonding step is performed in which the sheet is heated and pressed. The sheet thermocompression bonding process will be described below with reference to FIG.

The sheet 12 used in the sheet thermocompression bonding process can be selected from polyolefin-based or polyester-based sheets, and in this embodiment, a polyethylene sheet, which is a polyolefin-based sheet, is selected. As shown in FIG. 2, the sheet 12 has a base 12a and two equal sides 12b so that it can be adhered to the back surface 10b forming the dome-shaped recess 10d of the infrared lens 10 without gaps. It is prepared in sheets cut into triangles. In this embodiment, the entire back surface 10b is set to be covered with ten sheets 12, and the apex angle at the vertex 12c formed by the equal sides 12b is about 36 degrees.

As shown in the figure, the apex 12c of the sheet 12 is positioned at the center of the dome-shaped recessed portion 10b, that is, at the center of the through hole 10c, and the sheet 12 is laid out without gaps like an umbrella. After all the sheets 12 have been laid without gaps, the entire sheet 12 is heated by a heating means (not shown) and pressed by a pressing member (not shown) formed to match the shape of the recess 10d inside the infrared lens 10. is thermocompression bonded to the back surface 10b. At this time, the target heating temperature of the sheet 12 is set to 90° C., which is about 30° C. lower than the melting temperature of the polyethylene sheet constituting the sheet 12, which is 120 to 140° C. Polyolefin-based sheets and polyester-based sheets generate adhesive strength when heated to a temperature close to their melting temperature. can be thermocompressed. Thus, the sheet thermocompression bonding process is completed.

After the sheet thermocompression bonding process is completed, the resin embedding process is carried out. The resin embedding step will be described below with reference to FIG.

As shown in FIG. 3A, a nozzle 60 for dripping liquid resin is positioned above the infrared lens 10 to which the sheet 12 is thermocompression bonded to the back surface 10b side. For the liquid resin 14 dropped from the nozzle 60, for example, an ultraviolet (UV) curable epoxy resin is selected.

As described above, the recessed portion 10d is formed on the back surface 10b side of the infrared lens 10, and the molten liquid resin 14 is dropped from the nozzle 16 toward the recessed portion 10d in a plurality of times. . Each time the liquid resin 14 is dropped into the recessed portion 10d, the dropped liquid resin 14 is irradiated with ultraviolet rays by an ultraviolet irradiation means (not shown), and the liquid resin 14 is solidified. The liquid resin 14 is embedded in the dome-shaped recess 10d by repeating the dropping of the liquid resin 14 and the solidification by the irradiation of ultraviolet rays a plurality of times. FIG. 3(b) shows a cross section taken along line BB in FIG. 3(a), showing a state in which the recess 10d is filled with solidified liquid resin 14 (hereinafter referred to as "resin 14"). It is shown. The method for burying the liquid resin 14 in the dome-shaped recess 10d of the infrared lens 10 is not limited to the procedure described above. Alternatively, after the recess 10d is filled with the liquid resin 14 in a molten state, it can be solidified by irradiating ultraviolet rays. In addition, in the present embodiment, an ultraviolet curable epoxy resin is selected as the resin 14 embedded in the recess 10d, but the present invention is not limited to this, and other liquid resins such as synthetic resins that harden over time are used. It may be appropriately selected from polymers, natural polymers, semi-synthetic polymers, and the like. The above completes the resin embedding process.

After the resin embedding process is completed, the cutting process is performed. When performing the cutting step, first, as shown in FIG. 4, an annular frame F having an opening capable of accommodating the infrared lens 10 is prepared, and the surface 10a of the infrared lens 10 is directed upward, that is, the solidified resin The infrared lens 10 is placed in the opening of the annular frame F with the 14 side facing downward, and the infrared lens 10 and the rear surface of the frame F are adhered with a dicing tape T having adhesiveness. As a result, the infrared lens 10 is held by the annular frame F with the dicing tape T therebetween.

After the infrared lens 10 is held by the frame F, it is transported to the cutting device 1 shown in FIG. A cutting device 1 shown in FIG. 5 cuts an infrared lens 10, and includes a device housing 4, a chuck table 6 mounted on the device housing 4 so as to be movable in the X-axis direction indicated by an arrow X, and a chuck table. and processing feed means (not shown) for processing and feeding 6 in the X-axis direction. A holding surface 8 made of porous ceramics is arranged on the upper end portion of the chuck table 6 to suck and hold the infrared lens 10 via a dicing tape T. As shown in FIG.

Clamps 20 for fixing a frame F holding the infrared lens 10 are arranged at intervals in the circumferential direction on the periphery of the chuck table 6 . As shown in the figure, imaging means 22 for detecting an area to be cut by imaging the infrared lens 10 held by the chuck table 6 is arranged above the moving path of the chuck table 6 . The above-described processing and feeding means may comprise, for example, a ball screw connected to the chuck table 6 and extending in the X-axis direction, and a motor for rotating the ball screw (not shown).

In the device housing 4 of the cutting device 1, a cassette 46 containing an infrared lens held by a frame F is mounted on a vertically movable cassette mounting table 48. As shown in FIG. The cassette mounting table 48 is moved up and down by a lifting means (not shown). In addition, the cutting apparatus 1 pulls out the infrared lens 10 before cutting from the cassette 46 and carries it out to the temporary placement table 50, and carries the cut infrared lens 10 positioned on the temporary placement table 50 into the cassette 46. means 52, a first conveying means 54 for conveying the uncut infrared lens 10 conveyed from the cassette 46 to the temporary placement table 50 to the chuck table 6, a cleaning means 56 for cleaning the cut infrared lens 10, A second conveying means 58 for conveying the cut infrared lens 10 from the chuck table 6 to the cleaning means 56 is provided.

The cutting device 1 is provided with a cutting means 24 having a spindle 30 housed in a spindle housing 26 and having a cutting blade 32 rotatably supported at its tip. The lens 10 is cut. The cutting means 24 is configured to be movable in the Y-axis direction parallel to the holding surface 8 and orthogonal to the X-axis direction and to be movable (up and down) in the Z-axis direction perpendicular to the holding surface 8. It is provided with indexing feed means (not shown) for indexing and feeding in the axial direction, and cutting feed means (not shown) for cutting and feeding the cutting means 24 in the Z-axis direction. The indexing feed means and the cutting feed means are a ball screw extending in the Y-axis direction connected to the cutting means 24 and a ball screw extending in the Z-axis direction connected to the cutting means 24 in the same manner as the above-described machining feed means. , and a motor for rotating each ball screw (not shown). The cutting blade 32 has a diameter of 78 mm, a cutting edge protruding amount of 13 mm, and a thickness of 0.2 mm. As described above, when the through hole 10c is formed at the top of the workpiece, the thickness of the cutting blade 32 is preferably set smaller than the diameter of the through hole 10c. By setting in this way, the through-hole 10c can be neatly divided into two halves.

A mode of cutting the infrared lens 10 by the cutting means 24 will be described in more detail with reference to FIGS. 5 and 6. FIG.

The infrared lens 10 held on the frame F via the dicing tape T is conveyed to the chuck table 6 of the cutting device 1, and the infrared lens 10 is placed with the dicing tape T side down, that is, the solidified resin 14 side down. Once placed, the frame F is fixed by the clamps 20, and the suction means is operated to hold it by suction.

Infrared lens 10 is held on chuck table 6, and processing/feeding means (not shown) is operated to position chuck table 6 directly below imaging means 22, and infrared lens 10 is imaged by imaging means 22. FIG. In the present embodiment, as shown in FIG. 6, the line L passing through the center of the infrared lens 10 is set as the cutting line. identify. The central point O of the infrared lens 10 can be calculated from the intersection of the perpendicular bisectors of the three straight lines connecting the three coordinates of at least three different points on the outer periphery of the infrared lens 10. Since it is also the center of the through hole 10c formed at the center of the infrared lens 10, the through hole 10c can be detected and detected as the center point of the through hole 10c.

Once the central point O of the infrared lens 10 is identified, a cutting line L to be cut passing through the central point O is identified. Next, the chuck table 6 is moved by the processing feed means and the index feed means, and the center point O of the infrared lens 10, which is the position where the cutting line L is started, is positioned directly below the cutting blade 32. As shown in FIG. The spindle 30 is rotationally driven by a motor (not shown) to rotate the cutting blade 32 in the direction indicated by the arrow in FIG. 6 at a rotational speed of 7000 rpm. Then, the cutting means 24 is lowered by a cutting feed means (not shown), and the cutting edge of the cutting blade 32 is cut by 0.4 mm from the top of the infrared lens 10, that is, the position of the center point O of the through hole 10c. The processing feed means is operated to feed the chuck table 6 with respect to the cutting means 24 in the X direction indicated by the arrow X at a speed of 5 mm/sec to cut the infrared lens 10 along the cutting line L. .

Once the infrared lens 10 has been cut to a depth of 0.4 mm by one movement, the cutting blade 32 and the chuck table 6 are returned to their original positions, and the cutting blade 32 is fed 0.4 mm in addition to the previous cutting feed amount. is lowered to feed the chuck table 6 in the X direction. By repeating such cutting, the infrared lens 10 is gradually cut along the cutting line L while increasing the feed amount by 0.4 mm. While repeating the cutting feed described above, the cutting blade 32 cuts the infrared lens 10 together with the resin 14 and reaches the dicing tape T, so that the infrared lens 10 is completely cut along the cutting line L and divided into two parts. The cutting process is completed. In this way, the infrared lens 10 made of a brittle material can be cut satisfactorily by gradually performing the cutting and feeding in multiple steps. It should be noted that the present invention is not necessarily limited to gradually performing cutting and feeding in a plurality of times. It is also possible to cut by one processing feed by, for example, making the cut.

FIG. 7(a) shows an end view of one of the infrared lenses 10 equally divided into two by performing the above-described cutting process, viewed from the cut surface side. After the cutting process, the infrared lens 10 has the resin 14 embedded in the recess 10d as shown in FIG. 7A. A removal step is performed. The resin 14 is embedded not directly on the back surface 10b of the infrared lens 10 but via the sheet 12 which is thermocompression bonded. It is The sheet 12 can be easily peeled off by heating it to near the melting temperature of the material forming the sheet 12 to soften it, or by cooling it to reduce its adhesive strength. Therefore, in the removing step in the present embodiment, while heating or cooling the entire infrared lens 10 including the sheet 12 and the resin 14, the sheet 12 and the resin 14 are removed from the recess of the infrared lens 10 as shown in FIG. removed from section 10d.

According to the processing method of the present embodiment, as described above, since the resin 14 is embedded in the recessed portion 10d formed on the back surface 10b side of the infrared lens 10, no cavity exists during the cutting process. Slight vibration caused by the presence of is suppressed, and chipping of the cut surface can be suppressed. In addition, since the back surface 10b forming the dome-shaped recess 10d of the infrared lens 10 is covered with the sheet 12 that can be thermocompressed and does not require an adhesive layer or the like, and the resin 14 is embedded, the adhesive or the like is applied to the infrared lens 10 side. The sheet 12 and the resin 14 can be removed from the infrared lens 10 divided into two without leaving any residue, and the dimensional accuracy and the crystal structure can be confirmed in a good state.

According to the present invention, various modifications are provided without being limited to the above-described embodiments. In the above-described embodiment, an infrared lens was presented as a dome-shaped work piece having a recessed portion on the inside made of a brittle material, but the work piece is not limited to this, and a dome-shaped work piece (For example, lenses for spectacles, etc.) may be used for other purposes. Further, in the above-described embodiment, an example in which the infrared lens 10 having the through hole 10c at the top is used as the workpiece is presented, but the present invention is not limited to this, and the infrared lens without the through hole 10c can also be used. Applicable.

Furthermore, in the above-described embodiment, the sheet 12 is a polyethylene sheet, but is not limited to this, and can be appropriately selected from a polyolefin sheet or a polyester sheet. When selecting from polyolefin sheets, for example, a polypropylene sheet or a polystyrene sheet can be selected in addition to the polyethylene sheet described above. When the sheet is selected from polyester sheets, it can be selected from, for example, a polyethylene terephthalate sheet and a polyethylene naphthalate sheet. When a sheet other than a polyethylene sheet is selected as the sheet 12 used for thermocompression bonding, the sheet 12 is heated in the sheet thermocompression bonding process because the temperature at which adhesive force is generated in the sheet 12 differs depending on the material of the sheet. The actual target heating temperature is appropriately adjusted according to the melting temperature of the selected sheet. The target heating temperature at that time is preferably selected from a temperature range about 30 to 50 ° C. lower than the melting temperature. Since the temperature is 220 to 240°C, it is about 190°C. The melting temperature of polyethylene terephthalate is 250 to 270°C, so it is about 200°C. It can be set in degrees Celsius.

1: Cutting device 4: Housing 6: Chuck table 8: Holding surface 10: Infrared lens 12: Sheet 14: Liquid resin (resin)
20: Clamp 24: Cutting Means 26: Spindle Housing 30: Spindle 32: Cutting Blade 60: Nozzle F: Frame T: Dicing Tape

Claims (4)

A processing method for cutting a dome-shaped workpiece made of a brittle material and having a recessed portion on the inside with a cutting blade,
A sheet thermocompression bonding step of laying a polyolefin-based or polyester-based sheet in the recessed portion and heating and crimping the sheet;
a resin embedding step of embedding and solidifying a liquid resin in the recesses formed by the thermocompression-bonded sheets;
a cutting step of holding the solidified liquid resin embedded in the workpiece on a chuck table and cutting the workpiece with a cutting blade;
a removing step of removing the liquid resin solidified together with the sheet;
consisting of at least
In the sheet thermocompression bonding step, the sheet cut into a substantially isosceles triangular shape is prepared, the vertex of the substantially isosceles triangular sheet is positioned at the center of the inside of the dome shape, and the entire inside of the dome shape is covered. A processing method that spreads and arranges like umbrella sticking . A processing method for cutting a dome-shaped workpiece made of a brittle material and having a recessed portion on the inside with a cutting blade,
A sheet thermocompression bonding step of laying a polyolefin-based or polyester-based sheet in the recessed portion and heating and crimping the sheet;
a resin embedding step of embedding and solidifying a liquid resin in the recesses formed by the thermocompression-bonded sheets;
a cutting step of holding the solidified liquid resin embedded in the workpiece on a chuck table and cutting the workpiece with a cutting blade;
a removing step of removing the liquid resin solidified together with the sheet;
consisting of at least
A brittle material constituting the dome-shaped workpiece is silicon, and a through hole is formed in the center,
A processing method in which, in the cutting step, the thickness of the cutting blade is smaller than the diameter of the through hole to bisect the through hole .

A brittle material constituting the dome-shaped workpiece is silicon, and a through hole is formed in the center,
2. The processing method according to claim 1, wherein in the cutting step, the thickness of the cutting blade is smaller than the diameter of the through-hole to bisect the through-hole. 4. The processing method according to any one of claims 1 to 3, wherein in said resin embedding step, the liquid resin is a liquid resin that is solidified by irradiation with ultraviolet rays, and the liquid resin is embedded in a plurality of times.

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