JPH08233543A - Thermal deformation measuring apparatus - Google Patents

Abstract

PURPOSE: To simply and accurately measure the two-dimensional out-of-surface thermal deformation of an article. CONSTITUTION: The thermal deformation measuring apparatus comprises a thermostatic chamber 2 for varying the temperature of a sample 11, means for measuring the deformation of the sample 11, and a controller for controlling the measurement of the deformation and the temperature of the chamber. The upper surface of the chamber 2 is covered with a transparent plate 3. An optical non-contact displacement meter 1 is provided above the plate 3. The meter 1 is scanned in a two-dimensional plane, the distance between the sample provided in the chamber 2 and the meter 1 is sequentially measured, and the measured results are recorded in a memory provided in the controller.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for measuring out-of-plane thermal deformation of an object, and more particularly to a thermal-deformation measuring apparatus suitable for measuring the two-dimensional distribution of out-of-plane thermal deformation of an object. Yes, and is particularly suitable for measuring the thermal deformation of electronic components.

[0002]

2. Description of the Related Art Electronic components such as semiconductor devices basically have a structure in which plate members having different linear expansion coefficients are laminated. Therefore, when such a temperature change of the electronic component is applied, the component is out-of-plane deformed by the bimetal effect and warped. As a result, stress may be applied to the components of the electronic component or the joint portion, which may cause destruction. As described above, in the development of electronic components, it is important to consider thermal deformation, and a thermal deformation measuring device is required in order to select materials to be used and evaluate prototype electronic components.

As a method for measuring the thermal deformation of electronic parts, there is a method of measuring the thermal deformation of a material by applying a needle to a sample to be measured, heating the sample, and measuring the displacement of the needle on the opposite side. -237476.

As another method for measuring the thermal deformation of electronic parts, the measuring method by the moire method is the 382th of Proceedings of the 41st Electronic Components and Technology Conference (1991).
Pages 387 (Proceedings of 4
1st Electronic Components
and Technology Conference
e, (1991), pp382-387).

[0005]

Of the above-mentioned conventional techniques,
The contact-type method using a needle can basically measure only one point. Although the displacement of multiple points can be measured by increasing the number of needles, the number is naturally limited, and
The disadvantage is that it is not possible to measure the displacements of a plurality of closely spaced points. In particular, as described above, since the thermal deformation of the electronic component often causes a warp, it is necessary to know the displacement of a plurality of continuous points, and this method is not suitable for this purpose.

The thermal deformation measuring method based on the moire method meets the above-mentioned object because it can measure an arbitrary displacement of a surface to be measured and can obtain two-dimensional information. However, since this method uses interference fringes of light, it requires a special technique for data processing to quantify the displacement, and there is a problem in measurement accuracy. Further, the measurable displacement range is also small.

It is an object of the present invention to provide an apparatus for easily and accurately measuring the two-dimensional distribution of out-of-plane thermal deformation of an object centered on an electronic component.

[0008]

In order to achieve the above-mentioned object, a thermal deformation estimation device is used for a constant temperature bath for changing the temperature of the sample, a means for measuring the deformation of the sample, a deformation measurement and a constant temperature bath temperature. A transparent plate is placed on the upper surface of the constant temperature bath, an optical non-contact displacement gauge is provided above the transparent plate, and the displacement gauge is scanned in a two-dimensional plane to control the constant temperature bath. This is achieved by successively measuring the distance between the sample provided inside and the displacement meter, and recording the measurement result in the storage device provided inside the control device.

As a means for scanning the displacement gauge, it is effective to use a screw motor stage driven by a pulse motor, and to perform positioning control of the stage by a digital control system by a controller. As a method of measuring the displacement, when measuring the distance between the sample and the displacement meter, the scanning of the displacement meter is stopped and left stationary for a certain period of time, and then the distance between the sample and the displacement meter is measured. It is effective to control the rotation of the screw so as to cancel the backlash of the screw of the screw type stage, and to move the displacement meter only once along the circumference of the measurement range before the displacement measurement. is there.

Further, a hole is made in the bottom surface of the constant temperature bath, a supporting member made of a material having a linear expansion coefficient of 1 ppm / ° C. or less is passed through the hole, and the lower end of the supporting member is fixed to a surface plate. By supporting the sample at the upper end, the measurement accuracy can be improved. It is desirable that this support member is composed of three quartz rods, a quartz plate is placed on the upper ends of the three support members, and the sample is placed on the quartz plate.

Further, as a method of heating the sample, it is preferable to set the temperature of the sample by sending high temperature air heated (temperature adjusted) by a hot air generator (heating / cooling device) into a constant temperature bath. Cooling is preferably performed by sending air cooled by a refrigerator into a constant temperature bath.

In the thermal deformation measuring device according to the present invention, the data of the distance between the sample and the displacement meter in the scanning of the same specifications performed twice or more is stored in the storage device, and the difference between any two sets of the data is stored. The amount of displacement of the sample can be obtained by calculation, and each scanning is performed by changing the temperature (that is, scanning of the same specification is performed twice or more by changing the temperature of the sample, and two arbitrary sets of By calculating the data difference), the amount of thermal deformation can be obtained. The principle of the optical displacement meter is to measure the distance between the sample and the displacement meter by reflecting the laser light generated by the semiconductor laser generating element on the sample and detecting the position of the reflected light with a semiconductor position sensor. desirable. The addition of the function of displaying the displacement amount of the sample on the display device to the control device meets the object of the present invention.

[0013]

In the thermal deformation measuring apparatus according to the present invention, the upper surface of the constant temperature bath is covered with a transparent plate, an optical non-contact displacement meter is provided above the transparent plate, and the displacement meter is scanned within a two-dimensional plane. The distance between the sample and the displacement meter provided in the thermostatic chamber can be sequentially measured, and the measurement result can be recorded in the storage device provided in the control device. The distribution can be obtained with high accuracy.

A pulse motor driven screw type stage is used as a means for scanning the displacement meter, and the positioning control of the stage is performed by a digital control system by a control device, and further, the backlash of the screw of the screw type stage is canceled. Since such screw rotation control is performed at any time, the positioning accuracy of the displacement gauge is high. Further, make a hole in the bottom surface of the thermostatic chamber, pass a supporting member made of a material having a linear expansion coefficient of 1 ppm / ° C or less into the hole, fix the lower end of the supporting member to the surface plate, and sample at the upper end of the supporting member. Since it is supported, it is not affected by thermal deformation or vibration of the constant temperature bath. Further, since the temperature of the sample is adjusted by sending the air whose temperature has been adjusted by the heating / cooling device into the constant temperature bath, the heating / cooling rate of the sample is high and the temperature distribution is small.

In the thermal deformation measuring device according to the present invention, the data of the distance between the sample and the displacement meter in the scanning of the same specification performed twice or more is stored in the storage device, and the difference between any two sets of the data is stored. Since the displacement amount of the sample is obtained by the calculation, the thermal deformation with respect to an arbitrary temperature change can be easily obtained.

The principle of the optical displacement meter is to reflect the laser beam generated by the semiconductor laser generating element on the sample,
A method of measuring the distance between the sample and the displacement gauge by detecting the position of the reflected light with a semiconductor position sensor is used.
At the time of measurement, the scanning of the displacement meter is stopped, the scanning is stopped for a certain period of time, and then the distance between the sample and the displacement meter is measured. Therefore, the measurement accuracy is high and the data processing is easy.
Since a function of displaying the displacement amount of the sample on the display device is added to the control device, the measurer can easily understand the two-dimensional distribution of the out-of-plane displacement of the sample.

[0017]

Embodiments of the present invention will be described below with reference to the drawings. 1 is a perspective view showing an outline of an embodiment of the present invention, and FIG. 2 is a sectional view showing an outline of an embodiment of the present invention.
The constant temperature bath 2 is installed on a surface plate 9 via a support column 10. The upper surface of the constant temperature bath 2 is covered with a transparent plate 3. As the material of the transparent plate 3, for example, heat resistant glass is used. Further, by making this glass a double glass structure, it is possible to improve the heat insulating efficiency of the constant temperature bath. The bottom surface of the constant temperature bath 2 is provided with three holes, and the support member 4a,
4b and 4c are threaded. Support members 4a, 4b, 4c
It is necessary to use a material with a small linear expansion coefficient,
For example, quartz is used. The shape of the support member is a column shape or a pipe shape.

A sample mounting plate 5 is placed on the upper ends of the supporting members 4a, 4b, 4c. The sample mounting plate 5 also uses quartz. Further, a sample 11 is placed on the sample setting plate 5. A stage 7b for moving in the y direction is fixed on the surface plate 9, and a stage 7a for moving in the x direction is further fixed thereon. A pulse motor driven screw type stage is used for these stages. Stage 7a
The displacement gauge 1 is fixed to the via a displacement gauge support jig 6. The displacement gauge support jig 6 is adjusted so that the displacement gauge 1 is located above the sample 11.

In this embodiment, the visible laser light generated by the semiconductor laser generating element is reflected on the sample, and the position of the reflected light is detected by the semiconductor position sensor to measure the distance between the sample and the displacement meter. A displacement meter was used.
Therefore, since the laser light that hits the sample can be visually observed, the measurement position can be easily known. A duct 8a for supplying hot air and a duct 8b for exhausting air are connected to the side surface of the constant temperature tank 2, and although not shown in the figure, the duct 8a is connected to a hot air generator by a heat insulating pipe. .

In FIG. 2, the flow of air is shown by arrows. 1 and 2, the electric wiring connected to the displacement meter 1 and the stages 7a and 7b is omitted.

FIG. 3 shows a control diagram in the embodiment of the present invention. In this embodiment, the control device is composed of a computer, a display, a stage controller, a displacement gauge controller, and a temperature controller.

Data input / output is performed using a computer, and includes a stage controller, a displacement gauge controller,
The temperature controller operates according to the command of the computer,
It controls the stage, displacement meter, and hot air generator. The data measured by the displacement meter is transferred to the computer and recorded in the storage device built in the computer.
Appropriate data processing is applied to the measurement data by the computer and displayed on the display.

FIG. 4 is a flow chart showing the operation of the thermal deformation measuring apparatus of this embodiment. The measurement procedure will be described below with reference to this figure. In this embodiment, in order to measure the two-dimensional out-of-plane thermal deformation distribution of the sample, the displacement gauge is moved to each grid point in the rectangular area. Therefore, first, the measurement intervals and the number of measurement points in both the x and y directions are input.

Next, the number of measurements (the number of temperature steps) and the set temperature at each step are input. Prior to the measurement, the displacement meter is rotated once around the circumference of the measurement area.
The measurement area can be confirmed by the operator visually observing the laser light from the displacement meter that hits the sample.

At this time, if the measurement area is wrong,
Return to the beginning (this function is omitted in FIG. 4). Then start measuring. First, the displacement meter is moved to the origin of the coordinates, and the temperature of the constant temperature bath is controlled to the set value of step 1. When the temperature stabilizes, move the displacement gauge in the x direction by dx. After the displacement meter is stationary, the distance between the sample and the displacement meter is measured and the measured value is transferred to a computer and recorded. Nx by dx in x direction
After measuring the number of times, move dy in the y direction this time, and measure dx each in the x direction again Nx times. This operation is repeated Ny times in the y direction to complete the measurement of temperature step 1.

Although omitted in the flow chart, when the displacement is measured, the screw should always be rotated in the same direction and stopped. This is to prevent a reduction in positioning accuracy due to screw backlash. Next, the temperature is controlled to the set value in step 2 and the same displacement measurement is performed. When the measurement is completed up to the final temperature step, set the measurement conditions and measurement results to 1
Record as one dataset.

The measurement results are displayed by reading the data set into a computer. The predetermined data is calculated and the result is displayed on the display. The predetermined calculation referred to here is, for example, calculation of the difference between the displacement of an arbitrary step and the displacement of another step, and the thermal deformation caused between these steps can be obtained by this calculation.

Since the thermal deformation measuring apparatus according to the present embodiment performs the measurement by scanning the displacement gauge in a two-dimensional plane, the two-dimensional distribution of out-of-plane thermal deformation of the sample can be obtained with high accuracy. Positioning accuracy of the displacement meter is achieved by using a digitally controlled pulse motor driven screw type stage as a means to scan the displacement meter, and at the same time performing screw rotation control to cancel the screw backlash of the screw type stage. Is extremely high.

Furthermore, since the sample is directly supported on the surface plate through the quartz support member having a small linear expansion coefficient, the sample is not in contact with the constant temperature tank and is subject to the influence of thermal deformation and vibration of the constant temperature tank. There is no. Further, since the sample is heated by sending the high temperature air heated by the hot air generator into the constant temperature bath, the temperature rising rate of the sample is high and the temperature distribution is small.

The principle of the optical displacement meter is that the laser beam generated by the semiconductor laser generating element is reflected on the sample,
Since the method of measuring the distance between the sample and the displacement meter by detecting the position of the reflected light with the semiconductor position sensor is used, the measurement accuracy is high and the data processing is easy.

Further, at the time of measurement, the scanning of the displacement gauge is stopped and the scanning is stopped for a certain period of time, and thereafter the distance between the sample and the displacement gauge is measured. The error can be eliminated. Since the measurement data is processed by the computer and displayed on the display device, the measurer can easily understand the two-dimensional distribution of the out-of-plane displacement of the sample.

FIG. 5 shows an out-of-plane thermal deformation measurement example of an electronic device measured by the thermal deformation measurement apparatus according to the present embodiment prototyped by the inventor. It can be seen that the shape of thermal deformation is measured with extremely high accuracy and in an easy-to-understand manner.

[0033]

As described above, the thermal deformation measuring device according to the present invention can easily and accurately measure the two-dimensional out-of-plane thermal deformation of an object, so that the thermal deformation which is a problem in electronic parts can be grasped. Very useful to do.

[Brief description of drawings]

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

FIG. 2 is a sectional view of an embodiment of the present invention.

FIG. 3 is a control diagram of an embodiment of the present invention.

FIG. 4 is a flowchart showing the operation of the embodiment of the present invention.

FIG. 5 is a thermal deformation of an electronic component measured by the thermal deformation measuring device according to the embodiment of the present invention.

[Explanation of symbols]

1 ... Displacement meter, 2 ... Constant temperature bath, 3 ... Transparent plate, 4a, 4b, 4
c ... Support member, 5 ... Sample setting plate, 6 ... Displacement gauge support jig,
7a, 7b ... Stage, 8a, 8b ... Duct, 9 ... Surface plate, 10 ... Constant temperature bath supporting column, 11 ... Sample.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Asao Nishimura 502 Jinritsu-cho, Tsuchiura-shi, Ibaraki Hiritsu Seisakusho Co., Ltd.Mechanical Research Laboratory (72) Inventor Tatsuya Nagata 502 Kintate-cho, Tsuchiura-shi, Ibaraki Hiritsu Seisakusho Co., Ltd. Inside the mechanical laboratory

Claims (12)

[Claims] 1. A constant temperature bath for changing the temperature of a sample,
In a thermal deformation measuring device equipped with a means for measuring the deformation of a sample and a control device for controlling the deformation measurement and the temperature of a constant temperature bath, an upper surface of the constant temperature bath is covered with a transparent plate, and an optical non-contact is provided above the transparent plate. Of the displacement meter, the displacement meter is scanned in a two-dimensional plane to sequentially measure the distance between the sample and the displacement meter provided in the thermostatic chamber, and the measurement result is a storage device provided in the controller. A thermal deformation measuring device characterized by being recorded in. 2. The thermal deformation measuring apparatus according to claim 1, wherein a screw motor stage driven by a pulse motor is used as means for scanning the displacement gauge, and positioning control of the stage is digitally controlled by the controller. A thermal deformation measuring device, characterized in that 3. The thermal deformation measuring device according to claim 1, wherein a hole is formed in the bottom surface of the constant temperature bath, and a supporting member made of a material having a linear expansion coefficient of 1 ppm / ° C. or less is passed through the hole, A thermal deformation measuring device, characterized in that a lower end of a supporting member is fixed to a surface plate and an upper end of the supporting member supports a sample. 4. The thermal deformation measuring device according to claim 1, wherein the temperature of the sample is set by sending air whose temperature has been adjusted by a heating / cooling device into the constant temperature bath. 5. The thermal deformation measuring device according to claim 1, wherein the measurement data of the distance between the sample and the displacement meter in the scanning of the same specifications performed twice or more is stored in the storage device,
A thermal deformation measuring device characterized in that a displacement amount of a sample is obtained by calculating a difference between arbitrary two sets of the data. 6. The thermal deformation measuring device according to claim 1, wherein the laser beam generated by the semiconductor laser generating element is reflected on the sample, and the position of the reflected light is detected by the semiconductor position sensor, whereby the sample and the displacement meter. A thermal deformation measuring device characterized by using a displacement meter according to a method of measuring a distance between them. 7. The thermal deformation measuring device according to claim 2, wherein when measuring the distance between the sample and the displacement meter, the scanning of the displacement meter is stopped and the scanning is stopped for a certain period of time. A thermal deformation measuring device characterized by measuring a distance between the displacement gauges. 8. The thermal deformation measuring device according to claim 2, wherein rotation control of the screw for canceling backlash of the screw of the screw type stage is performed at any time. 9. The thermal deformation measuring device according to claim 2, wherein the displacement gauge is moved one round along the circumference of the measurement range prior to the displacement measurement. 10. The thermal deformation measuring device according to claim 3, wherein the supporting member is composed of three quartz rods, and a quartz plate is placed on the upper ends of the three supporting members, and the quartz plate is placed on the quartz plate. A thermal deformation measuring device, characterized in that a sample is placed on. 11. The thermal deformation measuring device according to claim 5, wherein scanning with the same specifications is performed twice or more while changing the temperature of the sample, and the difference between the two arbitrary sets of data is calculated,
A thermal deformation measuring device, characterized in that a thermal deformation amount of a sample is obtained. 12. The thermal deformation measuring device according to claim 5, wherein a function of displaying a displacement amount of a sample on a display device is added to the control device.