JP2604089Y2 - Grinder - Google Patents

Description

[Detailed description of the invention]

[0001]

This invention relates to a so-called so-called silicon substrate, in which a silicon substrate that is not oxidized is laminated on an insulating layer obtained by oxidizing a silicon substrate, and the substrate on the silicon substrate is left thin by processing to form a semiconductor on the silicon. The present invention relates to a grinding machine capable of quickly and accurately flattening a thin work such as an SOI substrate (Silicon on insulator) which requires a high film thickness accuracy without any trouble.

[0002]

2. Description of the Related Art Conventionally, in order to planarize a work such as an SOI substrate or an LSI device so that the film thickness is constant, a film thickness gauge is prepared separately from a grinding machine.
Grind the work with a grinder. Then, after removing the ground work from the grinder, the work is set on a film thickness meter, and the film thickness of the work is measured by the film thickness meter. Next, when the measurement result of the film thickness meter does not satisfy the desired specification value and the work has a portion that impairs flattening so that the film thickness is constant, that is, when there is a portion to be corrected in the work, the measured value is measured. The work is set on the grinding machine again, and only the portion to be corrected is ground.

[0003]

[Problems to be Solved by the Invention] However, conventionally, when flattening a work, it is necessary to set a ground work to a film thickness meter or to set a measured work to a grinder again. Takes time and effort,
Inefficient and inconvenient.

In particular, when the work is a thin plate such as an SOI substrate or the like, when the work which has been measured as described above is set again on the grinding machine, foreign matter such as dust adheres to the portion where the work is set. In addition, the above-described foreign matter causes extra deformation of the work, and the amount of deformation of the work at the time of setting on the grinding machine is different from that at the time of setting on the film thickness meter. It is impossible to achieve flattening so that the film thickness of the work becomes constant with high accuracy.

Moreover, when the work is an SOI substrate or the like,
It is necessary to input the film thickness distribution at a plurality of locations measured outside the machine to the processing machine, which is troublesome. Also, only the time required to set the work that has been ground as described above on the film thickness meter,
Since an extra oxide film is generated on the work that hinders accurate measurement with the film thickness meter, the measurement result has many errors, and only inaccurate measurement results can be obtained. It is difficult to accurately determine and grind, and the work cannot be flattened with high accuracy.

The present invention has been made in view of the above-mentioned circumstances, and its purpose is to quickly and accurately flatten even a work such as an SOI substrate which requires a high film thickness accuracy. It is to provide a grinding machine that can be achieved.

[0007]

In order to achieve the above object, the present invention provides a spindle unit that rotates while holding a work, a grindstone shaft unit that rotates a grindstone for grinding the work, In a grinding machine having such a unit and a table that reciprocates,
A film thickness gauge that is located on the table moving direction side and measures the film thickness at a plurality of locations of the work piece, and the work to be measured has undulation based on the measurement result of the film thickness meter.
Judge whether to work or not, and swell exists in the work
If it is determined that the thickness of the workpiece is constant,
For this purpose, the top of the undulation is
And the grinding condition setting means for setting, and characterized by providing a grinding instruction means for instructing to grind the workpiece according to the settings in the above grinding condition setting means.

[0008]

According to this invention, in order to measure the film thickness of a work with a film thickness gauge, the work is ground with a grindstone, that is, the work is simply removed from the chuck without removing the ground work from the chuck. After the measurement, the grinding condition setting means sets the reworking position and the cutting amount so that the film thickness of the work is constant based on the measurement result, and also provides a conditional grinding instruction. The means instructs to re-grind the workpiece in accordance with the settings (rework position and cutting amount) set by the grinding condition setting means.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the grinding machine according to the present invention will be described below in detail with reference to FIGS.

As shown in FIG. 1, the grinding machine includes a table 2 which reciprocates right and left on a base 1 and a spindle unit 3 is installed on the table 2. The spindle unit 3 rotates the work W on the table 2 while holding the work W. The spindle unit 3 has a rotatable spindle 4 and
A chuck 5 for holding the work W on the table 2 is provided at the tip of the main shaft 4.

A grinding wheel shaft unit 6 is provided above the table 2 as described above. The grinding wheel shaft unit 6 has a built-in rotatable grinding wheel shaft 7 and the grinding wheel shaft 7. A cup-shaped grindstone 8 for grinding the work W is attached to the tip of the.

Further, a film thickness gauge 9 such as an optical interference type is disposed on the base 1 on the side of the table 2 in the moving direction.
The film thickness meter 9 is configured to measure the film thickness of a plurality of ground workpieces and output the measurement result to the NC device 10.

The NC device 10 has a grinding condition setting function, a grinding instruction function, and the like. The grinding condition setting function makes the film thickness of the work W constant based on the measurement result of the film thickness meter 9. The reprocessing position is set as the top of the undulation of the ground work, and the grinding instruction function is set by the above grinding condition setting function (the reprocessing position and the cutting amount). An instruction is given to grind the work W according to the cutting depth.

A cleaning nozzle 11 is provided between the grinding wheel shaft unit 6 and the film thickness meter 9 and in the vicinity of the cup-shaped grinding wheel 8, and the cleaning nozzle 11 supplies pure water to the ground work W. Is configured to be sprayed.

Next, the operation of the grinding machine configured as described above will be described based on FIG. 2 with reference to FIG.

According to this grinding machine, the work W is supplied to the chuck 5 and the work is held at a predetermined position by the chuck 5 (step 100), and then the table 2 is rotated while the grindstone shaft 7 and the main shaft 4 are rotated. The grindstone shaft unit 6 is lowered to the main shaft unit 3 side through a cutting mechanism (not shown) while being reciprocated right and left. Thus, the work is cut and ground at a predetermined cutting speed while the cup-type grindstone 8 rotates (step 102).

Next, it is determined whether or not the grinding is completed based on the cut amount of the work or the like (step 104). at this point,
If it is determined that the grinding is not completed, step 10
Returning to the processing of step 2, steps 102 and 10
If it is determined that the grinding has been completed during the repetitive execution of the processing of No. 4, pure water is sprayed onto the work from the cleaning nozzle 11 to wash the work (step 106). Thereafter, the workpiece is spin-dried by rotating the main shaft 4 at about 2000 rpm (Step 108).

When the spin drying of the work is completed, the table 2 moves to the right until the work and the film thickness meter 9 face each other (step 110). Is measured. At this time, the thickness of the work W is 3 to 5 in the range from the center to the outer periphery of the work.
The location is measured, and the measurement result is output to the NC device 10 (Step 112).

Next, the NC apparatus 10 sets a rework position and a cutting depth for the work to be measured based on the measurement result from the film thickness meter 9. At this time, as a result of the determination based on the measurement result from the film thickness meter 9, when the thickness of the work is not uniform and the work has undulation, a portion serving as the top of the undulation is set as a rework position, and Instruct to re-grind the work according to the setting. (Step 114).

As a result, the table 2 is moved to the left so that the apex of the undulation of the work and the cup-shaped grindstone face each other (step 116). When this movement is completed, the process of step 102 is executed. Only the peaks of the undulations on the workpiece are re-ground.

As described above, the above steps 112 to 1
By repeatedly performing the processing of No. 16, the thickness of the work is made uniform and flattening is achieved. If the work is flattened, that is, if the thickness of the work becomes uniform as a result of the determination based on the measurement result from the film thickness meter 9 in step 114, the work is transferred from the chuck 5 to the work. Is removed to finish the grinding (step 118). Further, when the work is flattened but the film thickness is thinner than a desired film thickness, the work is removed from the chuck 5 and grinding is completed. In this case, the work is treated as an unrated defective product. (Step 120).

FIG . 3 shows an example in which the grinder according to the present invention is applied to a cylindrical grinder. A table 2 is provided on a base 1 for reciprocating left and right.
A spindle unit 3 is provided on the upper side, and a film thickness gauge 9 is installed on the base 1 on the moving direction side of the table 2 to measure a ground work with the film thickness meter 9. Is the same as that of the grinding machine of the above embodiment, and the detailed description thereof is omitted.

Further, in such a cylindrical grinder, similarly to the grinder of the above-described embodiment, the NC device 10 determines the reworking position and the cutting position for the work to be measured based on the measurement result from the film thickness meter 9. Set the loading amount. At this time, as a result of the judgment based on the measurement result from the film thickness meter 9, when the thickness of the work is not uniform and the work has undulation, a portion serving as the top of the undulation is set as a rework position, The grindstone 12 regrinds the work W according to the setting, and the film thickness of the work W is made uniform.

Therefore, according to the grinding machine of the above-described embodiment, in order to measure the film thickness of the work with the film thickness meter, it is necessary to remove the ground work from the chuck while the work is ground with the grindstone. Instead of simply moving the table to the thickness gauge side, it is not necessary to set the ground work to the thickness gauge or to set the measured work to the chuck again. Needless to say, it is not necessary to remove the work from the chuck until the work thickness can be made uniform. Not only can the deformation amount of the work during measurement and re-grinding be always the same, It is also possible to prevent an extra oxide film from being generated on the work, which hinders accurate measurement, and it is possible to accurately determine only the top of the waviness of the work from the measurement result and to grind the SO. In the work of thin plate thickness accuracy is required as such a substrate, it is possible to uniform the film thickness effort without quickly and accurately.

In the present embodiment, the spindle unit to which the work is fixed is set on the reciprocating table, and the work is moved to the fixed film thickness meter side. However, a method in which the spindle unit to which the work is fixed is fixed, the film thickness gauge is installed on the reciprocating table, and moved to the work side may be used.

In the grinding machine according to the present invention, in order to measure the film thickness of the work with the film thickness meter as described above, the work is ground with a grindstone, that is, without removing the ground work from the chuck. Since the table can be moved simply by moving the table to the thickness gauge side, the labor and time required for setting the ground work to the thickness gauge and setting the measured work to the chuck again can be eliminated. Needless to say, it is not necessary to attach and detach the work from the chuck until the film thickness of the work can be made uniform. Not only can the amount of deformation of the work at the time of measurement and at the time of re-grinding be always the same, the exact impede measurement can also prevent the oxide film is excessively generated in the work, since only a precise determination to fix to the part to the work from the measurement results it is possible to grind, especially , Even a thin plate of the workpiece thickness accuracy is required as such SOI substrate, it is possible to uniform the film thickness effort without quickly and accurately. In particular, according to the present invention,
For example, based on the measurement result of the film thickness meter,
Judge whether swell exists or not, and
If it is determined that a swell exists,
Adopts a configuration in which the part is set as the re-machining position with the whetstone.
In this way, the swell existing in the workpiece is supported.
To grind the top of the undulation,
Ensure that the work film thickness becomes uneven due to the residual undulation of this type.
In this respect, it is possible to prevent workpieces with high precision flattening and film formation.
It is suitable for achieving a uniform thickness.

[Brief description of the drawings]

FIG. 1 is a front view showing an embodiment of a grinding machine according to the present invention.

FIG. 2 is an explanatory view of the operation of the grinding machine according to the present invention.

FIG. 3 is a plan view showing another embodiment of the grinding machine according to the present invention.

[Explanation of symbols]

 2 Table 3 Spindle unit 6 Wheel axis unit 9 Film thickness meter 10 NC device (grinding condition setting means, grinding instruction means)

Continuation of front page (56) References JP-A-3-149181 (JP, A) JP-A-2-284865 (JP, A) JP-A-6-39707 (JP, A) JP-A 1-27855 (JP) JP-A-4-372362 (JP, A) JP-A-63-185574 (JP, A) JP-A-2-22496 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB Name) B24B 49/00-49/04

Claims (1)

(57) [Scope of request for utility model registration] 1. A spindle unit that rotates while holding a work, a grindstone shaft unit that rotates a grindstone for grinding the work, and any one of the above units is installed.
A grinding machine having a table that reciprocates; a film thickness meter that is positioned on the movement direction side of the table and measures film thickness at a plurality of locations of the work; and a measurement target based on a measurement result of the film thickness meter. For work
Judge whether swell exists or not, and
If it is determined that there is undulation,
In order to make it constant, the top of the swell is
A grinding machine, comprising: grinding condition setting means for setting as a reworking position; and grinding instruction means for instructing to grind the workpiece in accordance with the setting of the grinding condition setting means.