JPS62199354A - Automatic lapping finish method and device for crystalline plate and the like - Google Patents

Abstract

PURPOSE:To improve a yield, thickness precision and productivity by keeping pressure and the number of revolutions at a predetermined level after the bootstrapping thereof in turn on a preset lap pattern, shutting down said pressure and number in turn when a work thickness has reached a predetermined value and finishing lapping work when the work thickness has become a target value. CONSTITUTION:A setting device 5 is turned to a lap pattern for the number of revolutions and pressure information for each bootstrapping time, steady operation and each shutdown thickness, and said pattern is stored in a memory device 6. An instruction means 7 enters the output signals of a timer means 3 and a thickness measurement means 4 and discriminates time and thickness, thereby outputting the number of revolutions and pressure information from the memory device 6. And a control means 8 controls the number of revolutions and pressure, according to the output signal of the instruction means 7. Therefore, lapping work becomes easy very much, a yield is remarkably improved, a target thickness is kept at a good precision level and productivity is improved.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an automatic lapping method and device for crystal plates, etc., which makes it extremely easy to wrap crystal plates, etc., and prevents the wrapping of crystal plates, etc. It is characterized by a marked improvement in the thickness, a good accuracy with respect to the target thickness, and an improvement in productivity.

[Conventional technology]

For crystal plates and the like used in the production of ICs and the like, it is desirable that the thickness be precisely at a desired constant value and that the surface be perfectly flat. For this reason, a workpiece such as a crystal plate sliced from a crystal body or the like is subjected to lapping finishing.

Various types of such lapping finishing devices have been provided in the past, but basically they consist of rotating and lapping plates that are placed opposite each other and can freely apply pressure to the workpiece, and the workpiece is held between the lapping plates and pressurized. It was used to create a lapping finish by rotating it.

However, all of the conventional lapping devices described above are simply equipped with measuring instruments such as a tachometer and a pressure gauge, and the number of rotations and pressure during lapping are determined by the operator's operations. Therefore, the operator relied on experience and intuition to perform lapping work by varying the pressure and rotational speed. For this reason, skill is required and reproducibility is poor.
There were drawbacks such as poor yield and y* degree relative to the target thickness.

[Problem that the invention seeks to solve]

The present invention eliminates the above-mentioned drawbacks of the prior art, and makes it extremely easy to wrap crystal plates, etc., and the yield of crystal plates, etc. is significantly improved, and the precision with respect to the target thickness is good, and productivity is also improved. [Means for Solving the Problems] In order to solve the above problems, the automatic lapping method of the invention of Fang first consists of the following steps: A workpiece such as the above is held between opposing lap plates that rotate and can freely pressurize the workpiece. Next, according to a preset lapping pattern, the pressure applied to the workpiece K and the number of rotations of the lapping plate are gradually increased as time passes from the start of lapping, and then maintained at the set constant values. After that, when the thickness of the workpiece reaches the set value, the pressure and rotational speed are sequentially decreased as the thickness of the workpiece becomes thinner, and the lapping is completed when the thickness of the workpiece reaches the target value w:a.

Moreover, the automatic lapping finishing apparatus of the second invention is an apparatus for carrying out the method of the first invention, and includes a lapping plate which is arranged to rotate and can freely apply pressure to the workpiece, and a lapping plate that can rotate and apply pressure to the workpiece from the time of starting lapping. A timer means for measuring the elapsed time and a workpiece thickness measuring means are provided. , further comprising a setting device, a storage device, a command means, and a control means.

The setting device is used to set a lap pattern consisting of rotation speed and pressure information for each startup time, steady operation, and each fall thickness, and the set lap pattern is stored in the storage device. The output signal of the timer means and the thickness measuring means is input to the command means, which determines the elapsed time and the thickness of the workpiece, and extracts and outputs the rotation speed and pressure information corresponding to the state from the storage device. It is something. Further, the control means receives the output signal from the command means and controls the rotation speed and pressure to correspond to the output signal.

[Effect]

According to the present invention, in a preset lapping pattern, the pressure applied to the workpiece and the number of revolutions of the lapping plate are gradually increased as time elapses from the start of lapping, and then maintained at the set constant value.

Therefore, damage to the workpiece that is likely to occur at the beginning of lapping is prevented, and the time required for lapping is shortened, improving productivity.

That is, at the start of lapping, the surface of the sliced workpiece is rough and has minute protrusions, so when high pressure is applied, stress is concentrated on the protrusions, resulting in damage to the workpiece. However, in the present invention, since the pressure is low at the start of lapping, damage to the workpiece is prevented. Also,
As the lapping progresses, the above protrusions are gradually shaved off, and the contact area between the lapping plate and the workpiece expands, so the workpiece gradually becomes able to withstand high pressure, and in general, the workpiece The higher the rotation speed, the higher the pressure it can withstand.

In the present invention, the pressure and rotational speed increase sequentially and then shift to steady operation at relatively high pressure and rotational speed, so the time required for lapping is shortened as much as possible without damaging the workpiece.

Furthermore, according to the present invention, when the steady operation is continued and the thickness of the workpiece reaches the set value, the pressure and rotational speed decrease sequentially as the thickness of the workpiece becomes thinner, and when the thickness of the workpiece reaches the target value, Since the lapping finish is completed, the precision with respect to the target thickness of the workpiece is improved, and damage to the workpiece is also prevented. In other words, the rotation speed is sufficiently lowered just before the thickness of the workpiece reaches the target value, so the rotation of the lap plate can be stopped immediately when the target value is reached. This prevents excessive lapping, etc., and improves accuracy with respect to the target thickness of the workpiece. In addition, the workpiece cannot withstand high pressure and breaks at low rotational speeds, but in the present invention, the pressure is lowered at the same time as the rotational speed.
Damage to the workpiece is also prevented.

Further, in the present invention, the above-described changes in pressure and rotational speed are automatically performed according to a preset lap pattern, resulting in good reproducibility and easy operation.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS The method and apparatus of the present invention will be explained below based on embodiments shown in the drawings.

FIG. 1 is a block diagram showing the basic configuration of the apparatus of the present invention. In the apparatus of the present invention, as shown in the second diagram, a lapping plate 2 which is provided facing each other and is capable of pressurizing a workpiece IK such as a rotating and crystal plate, and a timer means 3 which opens the time elapsed from the start of lapping, A thickness measuring means 4 for the workpiece 1 is provided. Furthermore, a setting device 5, a storage device 6, a command means 7, and a control means 8 are provided. The setting device 5 sets a lap pattern consisting of time for each start-up, rotation speed and pressure information for each constant run and thickness for each fall,
The set wrap pattern is stored in the storage device 61c. Further, the command means 7 receives the output signals of the timer means 3 and the thickness it ma" means 4, determines the elapsed time and the thickness of the workpiece 1, and stores the rotation speed and pressure information corresponding to the state. It is taken out from the device 6 and output. Further, 1± the control means 8 is the command means 7.
The rotation speed and pressure are controlled according to the output signal of the engine.

Figures 2 to 6 show more specific embodiments of the apparatus of the present invention.

2 is a wrap plate, and an upper wrap plate 2α and a lower wrap plate 2h are provided facing each other. The upper and lower wrap plates 2α, 2b are connected to each gear box IOW, IO by the main motor 9.
They are configured to rotate at a predetermined ratio of rotational speeds via the respective rotation speeds.

Further, the upper lap plate 2α is connected to the piston rod 13 of the cylinder 12 via a connecting portion 11, and can pressurize the workpiece 1 held between the upper and lower lap plates 2α and 2b. That is, air compressor 14 to 1
High-pressure air can be supplied to the head cover side compartment 16 and rod cover side compartment 17 of the cylinder 12 through the 1HB*15.
The head cover side compartment 16 and the rod cover side compartment 17 can be opened to the atmosphere via. With this in mind, it is possible to change the air pressure in the head cover side compartment 16 and the rod cover side compartment 17 by simply controlling the electric Al 15, and the difference in pressure between the piston 18 and the piston 18 connected to the piston 18 can be changed. The upper lap plate 2α can be moved up and down, and the pressure applied by the upper lap plate 2α to the workpiece can be freely controlled. Note that the connection between the connecting portion 11 and the piston rod 13 is performed using the upper lap plate 2.
A ball bearing or the like (not shown) is used so as not to interfere with the rotation of α.

In the case of the embodiment shown in the drawings, the workpiece 1 is not only held by the upper and lower lap plates 2α, 2bI'1JIK, but is also configured to move planetarily, so that it can be polished more uniformly. That is, as shown in FIGS. 2 and 3,
A fixed outer gear 19, an inner gear 21 provided at the center of the outer gear 19 and rotated by an auxiliary motor 20, and an appropriate number of work holding gear plates meshed with the outer gear 19 and the inner gear 21. There are 22 or so.

And the work holding gear plate 22! ? : Work holding hole 2
3 is configured so that the workpiece 1 can be fitted therein. I want to do work l.

This is a ton that is caused to move planetarily by an auxiliary motor 20. However, it is not always necessary to make the work l move in a planetary motion. The thickness of the work holding gear plate 22 is made thinner than the target thickness of the work l, so that both surfaces of the work l always come into contact with the upper and lower lap plates 2α and 2b during lapping.

Next, referring to FIG. 4, 24 is a clock generator, 25 is a counter to which the output of the clock generator 24 is input, and the output side of the counter 25 is connected to the interface 29 of the microcomputer 26. There is. and.

The counter 25 is reset at the start of a lap. Therefore, the counter 25 outputs a signal corresponding to the elapsed time from the start of the lap. The clock generator 24 and counter 25 correspond to the timer means 3 in FIG. 21.

Further, 30 is a linear scale consisting of a fixed part 30α and a movable part 30b, which outputs a number of pulse signals corresponding to the moving distance of the movable part 30A with respect to the fixed part 30α. The fixed part 30α is attached to the main body of the cylinder 12, and the movable part 30b is attached to the piston rod 13 of the cylinder 12. Further, the output of the linear scale 30 is input to the counter 31, and the output of the linear scale 30 is input to the counter 31.
The output side of 1 is connected to the interface 29 of the microcomputer 26.

Therefore, if calibrated in advance, the distance between the upper and lower lap plates 2α and 2b when pressure is applied to the workpiece 1, or the output signal corresponding to the thickness of the workpiece 1, or the output signal output from the counter 31. It is.

That is, the linear scale 30 and the counter 31 correspond to the thickness measuring means 4 of the workpiece 1 in FIG.

Also, 32 is a keyboard, and 33 is a display.

Each is connected to an interface 29 of the microcomputer 26, and together with the microcomputer 26, constitutes the setting device 5 in FIG. That is, a display asking for the rotation speed and pressure information for each start-up time, steady operation, and each fall thickness that make up the lap pattern is displayed on the display 33 that receives a signal from the microcomputer 26, and while looking at the display, The operator can input a lap pattern using the keyboard 32. The input wrap pattern (1) is stored in a predetermined location in the memory 28 of the microcomputer 26. In other words, in the embodiment shown in the drawings, the microcomputer 26 also functions as the storage device i!6 in FIG. It is something to do.

The microcomputer 26 mainly includes a microprocessor (central processing unit) 27 and a memory (storage device) 28.
and an interface (input/output signal processing circuit) 29, and in the case of the embodiment shown in the drawing, in addition to functioning as a part of the setting device 5 and a storage device 6 as described above, as will be explained later, a command means 7 It also functions as a part of the control means 8.

Now, it is assumed that a wrap pattern as shown in FIG. 'l' 7-y
'! 'Ko, each standing position I) 2-D/ #Do1'
J: Pressure against 0? , and rotation speed N, , pressure ゛P2 for T1 and pressure P for rotation speed N2.112
J and rotation speed N! (In the case of this wrap pattern, it is steady operation). 0 indicates the start of wrapping, which is the thickness.

indicates the final target thickness of the workpiece 1. In addition, in the case of this wrap pattern, naturally TO<17<T
2, D2>Di>D□, Pi<Pr<PJ-PJ
>PJ>P, g, Ni <N2<N3. NJ>N
The relationship Hiroshi>N holds true, and its specific value is determined in consideration of the characteristics of the workpiece 1. In the case of the lap pattern shown in Figure 5, the pressure and rotational speed rise and fall in three stages, but they may rise and fall in more stages, and the number of stages can be entered by inputting the number of stages on the keyboard. It can also be changed freely. In addition, in the case of the lap pattern shown in Figure 5, the pressure and the rotation speed rise and fall at the same time, but they do not necessarily have to occur at the same time.Furthermore, during steady operation, the pressure P3 and the rotation speed NJ are constant. If necessary, if a wrapping pattern is used in which the pressure is lowered for a short period of time during steady operation as shown by the broken line in Fig. 5, the wrapping agent will contact the wrapping plate 2 when the pressure is lowered. This makes it easier to spread over the entire contact surface of the workpiece 1.

Next, the function of the microcomputer 26 as the command means 7 will be explained in the case where the wrap pattern shown in FIG. 5 is used. FIG. 6 is a flowchart for executing the function. In the figure, [phase] to @ indicate each step of the flowchart. Work 1 is held between upper and lower lap plates 2α and 2A.

After the lap pattern setting is completed, when a switch (not shown) is turned on, or when a nine lap pattern setting end signal supplied from another device is received, the process starts at step [phase].

At ①, PcN/sr/ data is read from the memory 28, and at @, P/, N, and data are output. Next, at @, the elapsed time T from the start of the lap is read from the counter 25, and at ■, the elapsed time T is compared with the TI data. T.I.
If the time has not passed, @ and ■ are repeated. 111
After , it changes to @.

At @, P1Nco, T-data is read, at @, P2,
N-data is output. Next, the elapsed time T is read again at @, and the elapsed time T is compared with the T2 data at @. If T2 has not elapsed, @ and @ are repeated.

After passing T-, it changes to @.

Pj, N3, Dλ data are read at @, and [
PJ and NJ data are output at [phase]. Next [phase]
The thickness D of the work l is read from the counter 31, and @
The thickness D is compared with the Dco data.

If it is thicker than D, ■ and @ are repeated.

When D- is reached, the process moves to 6).

Phiro #N4c-D/data is read in [phase],
plAa N4c data is output in ■, then [phase]
The thickness D of the workpiece 1 is read from the counter 31.

In (2), the thickness D is compared with D/data. If it is thicker than DI, [phase] and ■ are repeated. D, Pj, Hz
Data is output. Next, the thickness D of the workpiece 1 is read from the counter 31 in step 3, and the thickness D is compared with the Do data in phase. If it is thicker than DO, [phase] and [phase] are repeated. When it reaches Do, it changes to @.

A signal is output to set the value to 0, and the function as the command means 7 is terminated at @.

Further, in the case of the embodiment shown in the drawings, pressure sensors 70 and 71 are provided for detecting the air pressure in the head cover side compartment 16 and the rod cover side compartment 17 of the cylinder 12, respectively. The pressure sensor 70.71 is connected to the interface 29 of the microcomputer 26 via an amplifier 72.73 and a MU/D converter 74.75. And a pressure measuring means 76 that measures the pressure exerted by these on the workpiece IVc! jli! 1, a signal corresponding to the atmospheric pressure in the head cover side compartment 16 and the rod cover side compartment 17 is input to the microcomputer 26, and is converted into the above pressure by the microcomputer 26.

Also, the interface 2 of the microcomputer 26
9 is connected to a solenoid valve drive device 77 , and the output side of the nuclear solenoid valve drive device 77 is connected to the solenoid valve 15 . The microcomputer 26 functions as the command means 7 and sequentially outputs the pressure data P, , P2---
- (This is not actually output from the interface 29, but is processed within the microcomputer 26) and the actual pressure actually measured above, and a signal corresponding to the difference is sent to the interface. The electromagnetic valve driving device 77 receives the signal and drives the electromagnetic valve 15. That is, the pressure applied to the workpiece IK is maintained at a pressure determined by each pressure data p, , pλ-111 through so-called feedback control, and the microcomputer 26 is also used as part of the control means 8 in FIG. It's supposed to work. Motoo.

If other pressurizing means are employed, this feedback control is not necessarily required, and oven loop control may be used.

Further, a motor speed control device 78 is connected to the interface 29 of the microcomputer 26, and the output side of the motor speed control device 78 is connected to the main motor 9 and the sub motor 2.
Connected to 0. Therefore, the rotation speed data Nl are sequentially outputted from the interface 29 of the microcomputer 26 by the function as the command means.

NJ---one is input to the motor speed controller 78.

The motor speed control device 78 is composed of, for example, a D/A converter, an inverter, etc., and receives the rotation speed data N, , N
The main motor 9 and the sub motor 20 are rotated at a rotation speed corresponding to J-k. That is, in the case of the drawing example,
Regarding the rotation speed, the book says oven loop control is used.

In the figure, 79 is a lapping agent collection tank, 80 is a stirring motor, and 81 is a pump motor, and the lapping agent stirred by the stirring motor 80 is supplied between the lapping plate 2 and the workpiece 1 by the pump motor 81. It has become so.

According to the present invention having the above configuration, first, a workpiece 1 such as a crystal plate, etc.
is held between the upper and lower wrap plates 2α and 2h.

Next, a wrap pattern is set using the keyboard 32. In addition, when making this setting, instead of setting the rotation speed and pressure information for each start-up time, steady operation, and each fall thickness each time, you can select from among several preset wrap patterns. It's good.

After that, when a switch (not shown) is turned on, or when the lap pattern setting end signal is received.

The microcomputer 26 executes the flowchart shown in the above-mentioned arrow 6.

Therefore, the pressure applied to the workpiece 1 and the number of rotations of the lapping plate 2 are controlled according to the set lapping pattern.

After rising sequentially as time passes from the start of the lap, the constant value K (steady operation) is maintained.

Therefore, damage to the workpiece 1, which is likely to occur at the beginning of lapping, is prevented, and the time required for finishing lapping is shortened, thereby improving productivity.

In other words, at the start of wrapping, the sliced work 1
Since the surface of the workpiece 1 is rough and has minute protrusions, when high pressure is applied, stress will be concentrated on the protrusions and the workpiece 1 will be damaged. However, in the present invention, since the pressure is low at the start of lapping, damage to the workpiece 1 is prevented.
Also. As the lapping progresses, the protrusions are gradually shaved off and the contact area between the lapping plate 2 and the workpiece 1 expands, so the workpiece 1 gradually becomes able to withstand high pressure, and the general Since the workpiece 1 can withstand higher pressure as the rotational speed is higher, in the present invention, the pressure and rotational speed rise sequentially and then shift to steady operation at a relatively high pressure and rotational speed, so that the workpiece 1 is within a range where it will not be damaged. This reduces the time required for lapping as much as possible.

Furthermore, according to the present invention, when the steady operation is continued and the thickness of the workpiece 1 reaches the set value.

As the thickness of the workpiece 1 becomes thinner, the pressure and the number of rotations decrease sequentially, and when the thickness of the workpiece 1 reaches a target value, lapping is completed. Therefore, the precision with respect to the target thickness of the workpiece 1 is improved, and damage to the workpiece 1 is also prevented.

That is, the rotation speed is sufficiently reduced just before the thickness of the workpiece 1 reaches the target value.

Since the rotation of the lapping plate can be stopped immediately when the target value is reached, there is no possibility of excessive lapping due to the inertial force of the lapping plate 1.

This improves the accuracy with respect to the target thickness of the workpiece 1. Further, the workpiece 1 cannot withstand high pressure at low rotational speeds and is damaged, but in the present invention, the pressure is lowered at the same time as the rotational speed.

Damage to the workpiece 1 is also prevented.

In the present invention, one or more changes in pressure and rotational speed are automatically performed according to a preset lap pattern, resulting in good reproducibility and easy operation.

Note that the finished thickness of the work l is not a problem.

If only surface finishing is to be performed, the pressure and rotational speed are gradually reduced from when the thickness of the workpiece 1 reaches the set value during steady operation as it becomes thinner.

Instead of finishing lapping when the thickness of workpiece 1 reaches the target value, steady operation is performed for a set time, and then the pressure and rotational speed are gradually reduced as time elapses to finish lapping. It's a good thing.

It is clear that this lapping apparatus can be constructed by slightly changing the setting of the lapping pattern and the flowchart in the command means 7, and it is also possible to create a lapping apparatus having both functions.

In the explanation of the embodiments in the drawings, it is assumed that the read values of the thickness measuring means 4 and the pressure measuring means 76 directly correspond to the actual thickness or pressure, but in reality, the read values correspond to the pressure or the lap plate. It is desirable to store the correction value data in the memory 28 in advance and use the corrected value according to the measurement condition.

〔Effect of the invention〕

According to the present invention, wrapping work is extremely easy.

In addition, the winding of the crystal plate, etc. is significantly improved, the precision with respect to the target thickness is also good, the lapping time can be shortened, and productivity can be improved.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention, and Figure 1 is a block diagram, Figure 2 is a configuration diagram, and Figure 3 is a diagram of Fang 2.
Line cross-sectional view, 1%4 figure is a circuit diagram. ,? Figure 5 is an explanatory diagram of the wrap pattern, and Figure 6 is a flowchart. DESCRIPTION OF SYMBOLS 1...Workpiece, 2...-lap plate, 3...Timer means, 4...Thickness measuring means, 5...Setting device, 6...
- Storage device, 7... Command means, 8... Control means.

Claims (2)

[Claims] (1) A workpiece such as a crystal plate is held between opposing rotating lap plates that can freely apply pressure to the workpiece, and the pressure applied to the workpiece and the number of rotations of the lap plate are adjusted according to a preset lap pattern.
It starts up sequentially as time passes from the start of lapping, and then maintains it at the set constant value, and then when the thickness of the workpiece reaches the set value, it starts down sequentially as the thickness of the workpiece becomes thinner, until the thickness of the workpiece reaches the target value. An automatic lapping method for crystal plates, etc., characterized in that lapping is terminated when . (2) lapping plates arranged to face each other and capable of rotating and pressuring the workpiece; a timer means for measuring the elapsed time from the start of lapping; a means for measuring the thickness of the workpiece; each start-up time;
A setting device for setting a wrap pattern consisting of rotation speed and pressure information for steady operation and each falling thickness, a storage device for storing the wrap pattern set by the setting device, and output signals of the timer means and thickness measuring means. is input, a command means for determining the elapsed time and the thickness of the workpiece, and retrieving and outputting the rotation speed and pressure information corresponding to the state from the storage device; and a command means for receiving the output signal of the command means and outputting the corresponding rotation speed. and a control means for controlling pressure.