JPH06347343A - Method and apparatus for measuring stress - Google Patents

Abstract

(57) [Summary] [Object] An object of the present invention is to visualize and specify a measurement point to thereby obtain a stress value or a stress distribution in an extremely minute portion (sub-micrometer or nanometer order). An object of the present invention is to provide a stress measuring method and device for accurately determining the state. [Structure] An electron beam 2 emitted from an electron gun 1 is irradiated on a sample 6, secondary electrons generated are detected by a detector 7, and an image processing device 9 displays the surface morphology of the sample. Laser light source 1
The laser light 11 emitted from 0 is irradiated on the sample 6, the generated Raman scattered light is detected by the detector 16, and the obtained Raman spectrum is read by the computer 8. The stress value is calculated from the frequency shift value at each scanning point, and the image processing device 9
The stress distribution state is displayed by. Since the center of the screen of the image processing device 9 is set so as to coincide with the spot center of the electron beam and the spot center of the laser, the fine movement step is performed.
By moving the sample 6 with the jig 17 so that the measurement point coincides with the center of the screen of the image processing apparatus 9, the stress at the specified point can be measured.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for measuring stress on a minute portion, and particularly to a stress suitable for a case where a sample to be measured is extremely small like an LSI element and it is difficult to measure stress on a specific portion. The present invention relates to a measuring method and device.

[0002]

2. Description of the Related Art A conventional method for measuring stress in a minute portion is described in Applied Physics Letters, Vol. 40,
No. 10 (1982) 895 to 898 (A
ppl. Phys. Lett. , Vol. 40, NO.
10 (1982), pp 895-898), the content of the method and apparatus for stress measurement by Raman spectroscopy is discussed.

In this conventional technique, stress measurement is performed as follows. Monochromatic light that is strong to the sample to be measured (This equipment uses Ar ion laser or Kr ion laser)
When irradiated with, the incident light is frequency-shifted due to the molecular vibration of the sample, and Raman scattered light having a frequency different from that of the incident light is generated.

A measurement of the frequency-shifted Raman scattered light intensity is called a Raman spectrum. Qualitative analysis can be performed from the frequency position where the Raman spectrum shows a peak, and quantitative analysis can be performed from the scattered light intensity. When stress is applied, the frequency position where the Raman spectrum shows a peak shifts, and the stress is quantitatively evaluated by detecting the shift amount.

[0005]

The above-described conventional stress measuring method and apparatus use white light or the like to observe the morphology of the measurement sample and to specify the measurement position.
In the case of a sample, such as an LSI device, in which the structure changes intricately in a very small portion (sub-micrometer or nanometer order), it is difficult to visualize and specify the measurement location, so the measurement accuracy There was a flaw that made it worse.

The object of the present invention is to obtain a stress value or a stress distribution state of a very small portion (sub-micrometer or nanometer order) with high accuracy by visualizing and specifying a measurement point. It is to provide a measuring method and an apparatus.

[0007]

The above object is achieved by detecting secondary electrons generated by irradiation of an electron beam in a stress measuring method by Raman spectroscopy, and visualizing and specifying a measurement point. To be done.

Further, the above-mentioned object is, in an apparatus comprising a laser light source, an optical system such as a lens, a spectroscope and a detector, an electron gun for generating an electron beam, a scanning mechanism for scanning the electron beam and a sample. This is achieved by providing a detector for detecting the generated secondary electrons. Further, it is achieved by performing stress measurement in vacuum.

The stress measuring method of the present invention is characterized by any one of the following configurations. ◆ (1) A laser light source, an objective lens for narrowing the laser light into a spot on the surface of the object to be stressed, a half mirror for guiding scattered light to a spectrometer, and a spectroscope. In the stress measurement method using Raman spectroscopy provided, the secondary electron generated by irradiating an electron beam is detected, and the measurement value is visualized and specified to measure the stress value or the stress distribution state of the microscopic portion. To do.

(2) An ultraviolet laser light source, an ultraviolet objective lens for narrowing the ultraviolet laser light into a spot shape on the surface of the object to be stressed, and an ultraviolet harness for guiding scattered light to a spectrometer. In a stress measuring method by ultraviolet Raman spectroscopy provided with a humilla and a spectroscope, secondary electrons generated by irradiating an electron beam are detected to visualize and specify a measurement point, thereby obtaining an extremely small portion. Measure the stress value or stress distribution state of.

(3) In (1) or (2), the irradiation position of the electron beam and the irradiation position of the laser are matched, or the beam axis of the electron beam and the optical axis of the laser are matched. Or make the beam axis of the electron beam and the optical axis of the laser independent.

(4) In any one of (1) to (3), the stress measurement is performed in a vacuum, or the stress measurement is performed in a vacuum of about 10 μPa to 50 kPa.

The stress measuring device of the present invention is characterized by any of the following configurations. (5) Raman spectroscopy provided with a laser light source, an objective lens that focuses the laser light into a spot on the surface of the object to be stressed, a half mirror that guides scattered light to a spectrometer, and a spectroscope. The stress measuring device according to the method comprises an electron gun, a scanning mechanism for scanning an electron beam generated from the electron gun, and a secondary electron detector.

(6) Ultraviolet laser light source, an ultraviolet objective lens for narrowing the ultraviolet laser light into a spot shape on the surface of the object to be stressed, and an ultraviolet laser for guiding scattered light to a spectrometer. An ultraviolet Raman spectroscopic stress measurement device including a humiler and a spectroscope is provided with an electron gun, a scanning mechanism for scanning an electron beam generated from the electron gun, and a secondary electron detector.

(7) In (5) or (6), the irradiation position of the electron beam and the irradiation position of the laser are matched.
Alternatively, the beam axis of the electron beam and the optical axis of the laser are made to coincide with each other, or the beam axis of the electron beam and the optical axis of the laser are made independent.

(8) In (5) to (7), at least the optical path of the light of the laser or the ultraviolet laser or the path of the electron beam is evacuated, or at least the laser or the ultraviolet laser. The optical path of light or the path of electron beam is 10 μPa to 50 k
Make a vacuum of about Pa.

The above stress measuring method and stress measuring apparatus are suitable for use in a semiconductor manufacturing method and apparatus, and these semiconductor manufacturing method and semiconductor manufacturing apparatus are suitable for being applied to a semiconductor manufacturing process.

[0018]

As described above, by detecting the secondary electrons generated by irradiating the electron beam and visualizing and specifying the measurement location, the area of the sub-micrometer or nanometer order can be detected. It is possible to detect the stress value, and it is possible to measure the stress or stress distribution in the extremely small portion, which was difficult in the past.

Further, as described above, by providing the electron gun for generating the electron beam, the scanning mechanism for scanning the electron beam, and the detector for detecting the secondary electrons generated from the sample, the extremely small portion ( Since the stress or the stress distribution of the sub-micrometer or the nanometer order can be grasped with high accuracy, it is possible to perform highly accurate measurement.

Further, by performing the stress measurement in vacuum, it is possible to reduce the attenuation of the intensity of the laser light or the ultraviolet laser light or the intensity of the electron beam, and it is possible to perform the stress measurement with high accuracy. .

[0021]

Embodiments of the present invention will be described below with reference to the drawings. The embodiment shown in FIG. 1 is a basic mode of the stress measuring device of the present invention. In this figure, an electron beam 2 (accelerating voltage 0.1 to 0.1) emitted from an electron gun 1 (field emission type in this embodiment).
50 kV) passes through the condenser lens 3, the deflection coil 4, and the objective lens 5 and is applied to the sample 6. The secondary electrons generated from the sample 6 are detected by the detector 7, amplified by an amplifier (not shown), read into the computer 8, and the image processing device 9 displays the surface morphology of the sample.

Further, the laser light 1 emitted from the laser light source 10
1 passes through the mirror 12 and is focused by the objective lens 13 to irradiate the sample 6. Here, the minimum value of the spot diameter (irradiation diameter) on the sample 6 of the laser is approximately the same as the wavelength of the laser used. Further, the size can be changed to an arbitrary size by changing the optical system such as a lens.

The present invention also includes silicon, germanium,
The method and apparatus are suitable for the measurement of semiconductor materials such as gallium / arsenic compounds and carbon, graphite, diamond, and ceramics materials. In this embodiment, the case of using silicon as a sample will be described.

The Raman scattered light generated due to the molecular vibration of the sample 6 (silicon) passes through the objective lens 13, is guided to the spectroscope 15 by the half mirror 14, and is detected by the detector 16. Here, the detector 16 is a photomultiplier tube, a multi-channel detector, or a CCD (Charge Co).
A charged device (charge coupled device) detector or the like is used. The obtained Raman spectrum is read into the computer 8.

The sample 6 is placed on the fine movement stage 17, and the laser beam 11 is scanned on the sample 6 by moving the stage 17 (movement step amount 1 nm to 1 mm). , The Raman spectrum at each scanning position and position information from a position sensor (not shown) provided on the fine movement stage 17 are read into the computer 8.

Here, the fine movement stage 17 is provided with a moving mechanism (not shown) and can move in three axis directions (two horizontal axes and one vertical axis in this embodiment). Compu
The stress value is obtained from the frequency shift value at each scanning point by the computer 8, and the stress distribution state is displayed by the image processing device 9.

A mark (a cross shape in this embodiment) is provided at the center of the screen of the image processing device 9. This mark is the center of the spot of the electron beam 2 and the center of the spot of the laser beam 11. Is set to match.

The sample 6 is placed on the fine movement stage 17, and a position sensor (not shown) is provided on the stage 17, so that the sample 6 is located at an arbitrary position based on this position information. Can be moved. Therefore, by moving the sample 6 so that the measurement point of the sample 6 coincides with the mark at the center of the screen of the image processing apparatus 9, the stress at the specified point can be measured.

In the present embodiment, the center of the screen of the image processing apparatus 9 is set so as to coincide with the spot center of the electron beam 2 and the spot center of the laser beam 11. Select a place other than the center, provide a mark at that place, and place the spot center of the electron beam 2 and the mark on that mark.
You may set so that the spot center of the light 11 may correspond.

In this embodiment, the mirror-12 and the objective lens 1 are used.
3 and a harf mirror 14 are used, the mirror 12, the objective lens 13 and the harf mirror 14 are provided with a moving mechanism (not shown) so that they can be moved when the electron beam is irradiated. ing.

The embodiment shown in FIG. 2 is a basic aspect of another invention. In this figure, an electron beam 2 (accelerating voltage 0.1 to 50 k) emitted from an electron gun 1 (field emission type in this embodiment).
V) passes through the condenser lens 3, the deflection coil 4, and the objective lens 5 and is applied to the sample 6. 2 generated from sample 6
The secondary electrons are detected by the detector 7, amplified by an amplifier (not shown), then read by the computer 8, and the surface morphology of the sample is displayed by the image processing device 9.

Further, the ultraviolet laser light 20 emitted from the ultraviolet laser light source 19 passes through the ultraviolet mirror -21 and is focused by the ultraviolet objective lens 22 to irradiate the sample 6. Here, as the ultraviolet laser, Ar ion laser, N ₂ laser or He is used.
-Cd Le - The or H ₂ Les - The, Ar ₂ Le - The, Kr ₂ Le -
The, Xe ₂ laser, ArCl laser, ArF laser, K
rCl laser, KrF laser, XeF laser, XeBr
An excimer laser such as a laser, a XeCl laser, or a XeF laser is preferably used. As the ultraviolet objective lens 22,
It is preferable to use an alkali halide lens, especially a lens made of LiF, MgF ₂ or fluorite (CaF ₂ ).

It may be made of synthetic quartz, fused quartz made of natural quartz, sapphire glass (Al ₂ O ₃ ) or ultraviolet transparent glass. Further, the minimum value of the spot diameter (irradiation diameter) of the ultraviolet laser on the sample 6 is about the same as the wavelength of the ultraviolet laser used. Further, the size can be changed to an arbitrary size by changing the optical system such as a lens.

The present invention also includes silicon, germanium,
The method and apparatus are suitable for the measurement of semiconductor materials such as gallium / arsenic compounds and carbon, graphite, diamond, and ceramics materials. In this embodiment, the case of using silicon as a sample will be described.

Raman scattered light generated due to the molecular vibration of the sample 6 (silicon) passes through the ultraviolet objective lens 22,
It is guided to the spectroscope 15 by the Hafmirer 23 for ultraviolet rays and detected by the detector 16. The obtained Raman spectrum is read into the computer 8.

The sample 6 is placed on the fine movement stage 17. By moving the stage 17 (movement step amount 1 nm to 1 mm), the ultraviolet laser light 20 is scanned on the sample 6. Then, the Raman spectrum at each scanning position and position information from a position sensor (not shown) provided on the fine movement stage 17 are read by the computer 8.

Here, the fine movement stage 17 is provided with a moving mechanism (not shown) and can move in three axis directions (two horizontal axes and one vertical axis in this embodiment). Compu
The stress value is obtained from the frequency shift value at each scanning point by the computer 8, and the stress distribution state is displayed by the image processing device 9.

A mark (a cross shape in this embodiment) is provided at the center of the screen of the image processing apparatus 9, and this mark is the center of the spot of the electron beam 2 and the spot of the ultraviolet laser light 11. It is set to match the center. The sample 6 is placed on the fine movement stage 17, and this stage 17 is provided with a position sensor (not shown). Therefore, the sample 6 is moved to an arbitrary position from this position information. be able to.

Therefore, by moving the sample 6 so that the measurement point of the sample 6 coincides with the mark at the center of the screen of the image processing apparatus 9, the stress at the specified point can be measured.

In this embodiment, the center of the screen of the image processing apparatus 9 is set so as to coincide with the spot center of the electron beam 2 and the spot center of the ultraviolet laser light 20, but the screen of the image processing apparatus 9 is set. It is also possible to select a position other than the center of the mark and provide a mark at that position so that the spot center of the electron beam 2 and the spot center of the ultraviolet laser light 20 coincide with the mark.

In this embodiment, the ultraviolet mirror-21, the ultraviolet objective lens 22 and the ultraviolet Hafmir-23 are used. These ultraviolet mirror-21 and ultraviolet objective lens 2 are used.
2 and the ultraviolet Hafmira-23 are provided with a moving mechanism (not shown) so that they can move when irradiated with an electron beam.

In the embodiment shown in FIGS. 1 and 2 above,
Although the beam axis of the electron beam coincides with the optical axis of the laser light, it does not have to coincide. FIG. 3 and FIG. 4 show an embodiment in which they are not matched but independent. In the case of making it independent, after visualizing and specifying the measurement point by the electron beam, by moving or rotating the fine movement stage 26 having a movement or rotation mechanism (not shown), the position is specified at the specified point.
The sample may be installed so that the spot centers of the spots coincide with each other.

In FIG. 3, the laser light 11 emitted from the laser light source 10 passes through the mirrors 24 and 12 and the objective lens 13
And the sample 6 is irradiated with the light. The Raman scattered light generated due to the molecular vibration of the sample 6 passes through the objective lens 13 and the spectroscope 15 by the half mirror 14 and the mirror 25.
Is detected by the detector 16.

In FIG. 4, the ultraviolet laser light 20 emitted from the ultraviolet laser light source 19 passes through the ultraviolet mirrors 27 and 21 and is focused by the ultraviolet objective lens 22 to irradiate the sample 6. The Raman scattered light generated due to the molecular vibration of the sample 6 passes through the ultraviolet objective lens 22, and the ultraviolet Hafmyra-2.
3 and the ultraviolet mirror 28 for ultraviolet rays, the light is guided to the spectroscope 15 and detected by the detector 16.

The embodiment shown in FIG. 5 is an electron gun 1, a condenser lens 3, a deflection coil 4 in the embodiment shown in FIG.
The objective lens 5, the sample 6, the detector 7, the mirror 12, the objective lens 13, the half mirror 14, and the fine movement stage 17 are provided in the vacuum chamber 18.

In a high vacuum (10 μPa to 0.1 P
It may be provided in a low vacuum (100 Pa or more) or in the atmosphere, instead of in a) or the medium vacuum (0.1 to 100 Pa). However, since the electron beam has a large intensity attenuation in air, the attenuation can be reduced by performing the electron beam in a more vacuum atmosphere.

The embodiment shown in FIG. 6 is an electron gun 1, a condenser lens 3, a deflection coil 4 in the embodiment shown in FIG.
Objective lens 5, sample 6, detector 7, UV Mira-21,
An ultraviolet objective lens 22, an ultraviolet hafmiller 23, and a fine movement stage 17 are provided in a vacuum chamber 18.

These are placed in a high vacuum (10 μPa to 0.1 P).
It may be provided in a low vacuum (100 Pa or more) or in the atmosphere, instead of in a) or the medium vacuum (0.1 to 100 Pa). However, since the electron beam has a large intensity attenuation in air, the attenuation can be reduced by performing the electron beam in a more vacuum atmosphere.

The ultraviolet window 31 or 32 when the ultraviolet laser light 20 enters the vacuum chamber 18 or the Raman scattered light exits from the vacuum chamber 18 is an alkali halide, especially L.
A window made of iF, MgF ₂ or fluorite (CaF ₂ ) may be used. Made of synthetic quartz, fused quartz made from natural quartz,
It may be made of sapphire glass (Al ₂ O ₃ ) or ultraviolet transparent glass.

In the embodiment shown in FIG. 7, the electron gun 1, the condenser lens 3, the deflection coil 4 in the embodiment shown in FIG.
Objective lens 5, sample 6, detector 7, mirrors 12 and 24
And 25, the objective lens 13, the half mirror 14, and the fine movement stage 26 are provided in the vacuum chamber 18.

These are placed in a high vacuum (10 μPa to 0.1 P).
It may be provided in a low vacuum (100 Pa or more) or in the atmosphere, instead of in a) or the medium vacuum (0.1 to 100 Pa). However, since the electron beam has a large intensity attenuation in air, the attenuation can be reduced by performing the electron beam in a more vacuum atmosphere.

The embodiment shown in FIG. 8 is similar to the embodiment shown in FIG. 4 except that the electron gun 1, the condenser lens 3, the deflection coil 4,
An objective lens 5, a sample 6, a detector 7, ultraviolet mirrors 21 to 27 and 28 for ultraviolet, an objective lens 22 for ultraviolet, a Hafmira for ultraviolet 23, and a fine movement stage 26 are provided in a vacuum chamber 18. is there.

These are placed in a high vacuum (10 μPa to 0.1 P
It may be provided in a low vacuum (100 Pa or more) or in the atmosphere, instead of in a) or the medium vacuum (0.1 to 100 Pa). However, since the electron beam has a large intensity attenuation in air, the attenuation can be reduced by performing the electron beam in a more vacuum atmosphere.

The ultraviolet window 31 or 32 when the ultraviolet laser light 20 enters the vacuum chamber 18 or when the Raman scattered light exits from the vacuum chamber 18 is an alkali halide, especially L.
A window made of iF, MgF ₂ or fluorspar (CaF ₂ ) may be used. It may be made of synthetic quartz, fused quartz made of natural quartz, sapphire glass (Al ₂ O ₃ ) or ultraviolet transparent glass.

When an ultraviolet laser is used as the laser light source,
Since the attenuation of the laser light intensity may increase in the air, the attenuation can be reduced by performing it in a vacuum. A vacuum can be used even when using a normal laser whose intensity is not greatly attenuated in the air, but since the optical system to be used must have a vacuum specification, the cost is increased accordingly.

FIGS. 9 and 10 show an embodiment in which an ultraviolet laser is used. In these embodiments, the optical paths of the ultraviolet laser light 20 emitted from the ultraviolet laser light source 19 and the generated Raman scattered light are provided in the vacuum chamber 18. Also,
In these examples, the electron beam 2 and the path of the generated secondary electrons are provided in the vacuum chamber 18. Therefore, by making the optical path of the laser light or the path of the electron beam a vacuum, it is possible to accurately measure the stress value or the stress distribution state of the microscopic portion.

In the examples shown above, the electron beam
In the structure where the optical axis of the laser light coincides with the optical axis of the laser light, instead of the mirror 12, the objective lens 13 and the Haarmylar 14, or the ultraviolet mirror 21 for ultraviolet and the objective lens 22 for ultraviolet.
Instead of the Hafmira-23 for UV and the mirror, an integrated mirror such as a Cassegrain-Schwarz Child objective mirror (Cassegrain-Schwa) is used.
rzchild mirror objectiv
e), or a reflection microscope objective lens (Reflect)
ing Objective) may be used.

The mirror 12 and the objective lens 1
3 and Hafmira-14, or an ultraviolet mirror-21, an ultraviolet objective lens 22, an ultraviolet hafmirah-23, or a mirror in which these are integrated, for example, a Cassegrain Schwarzchild objective mirror ( Cassegra
in-Schwarzchild mirror ob
objective) or reflective microscope objective lens (R
The emissive object may be provided with a moving mechanism so that it can move when it is irradiated with an electron beam.

The embodiment shown in FIG. 11 is a basic aspect of another invention, is a semiconductor manufacturing apparatus with a stress measuring device, and is an example of a vacuum vapor deposition device.

According to this vapor deposition apparatus, a sample 6 such as a silicon substrate fixed to a stage 17 is arranged in a bell jar 33 forming a vacuum chamber, and a vapor deposition substance is placed facing the sample 6. A vapor deposition source 34 is provided. The sample 6 is heated to a predetermined temperature by a heater 35, and a negative DC bias voltage 37 is applied.

The bell jar 33 is evacuated to a vacuum of about 1 to 10 kPa by a vacuum pump (not shown). The evaporation source 34 is heated and evaporated by an electron gun heating method (not shown) and evaporated on the sample 6, while the stress at the laser irradiation point is measured by in-situ observation by a stress measuring device. The configuration and operation of the stress measuring device have been described above.

The embodiment shown in FIG. 12 is a basic embodiment of another invention, which is a semiconductor manufacturing apparatus equipped with a stress measuring device using an ultraviolet laser, and particularly an example of a vacuum vapor deposition device.

According to this vapor deposition apparatus, the sample 6 to be measured such as a silicon substrate fixed to the stage 17 is arranged in the bell jar 33 forming the vacuum chamber, and the vapor deposition substance is opposed to the sample 6. A vapor deposition source 34 containing is placed. The sample 6 is heated to a predetermined temperature by a heater 35, and a negative DC bias voltage 37 is applied.

The bell jar 33 is evacuated to a vacuum of about 1 to 10 kPa by a vacuum pump (not shown). The evaporation source 34 is heated and evaporated by an electron gun heating method (not shown) to be evaporated on the sample 6, and the stress at the ultraviolet laser irradiation point is measured by in-situ observation with a stress measuring device. The configuration and operation of the stress measuring device have been described above.

The ultraviolet window 31 when the ultraviolet laser light 20 enters the bell jar 33 or when the Raman scattered light emerges from the bell jar 33 is an alkali halide, especially LiF.
A window made of MgF ₂ or fluorite (CaF ₂ ) may be used. It may be made of synthetic quartz, fused quartz made of natural quartz, sapphire glass (Al ₂ O ₃ ) or ultraviolet transparent glass.

The procedure for visualizing, specifying, and measuring stress at the measurement points in the present invention is as follows, as shown in the basic flow chart of FIG. ◆ First step: Specify the measurement conditions, the number of measurement data or the number of measurement repetitions.

Second step: The sample is irradiated with an electron beam and the generated secondary electrons are detected. ◆ Third step: Observe the sample morphology (visualization) and select the measurement point.

Fourth Step: The sample is moved so that the selected measurement point and the laser irradiation point coincide with each other (specification of the measurement point). ◆ Fifth step: The laser is irradiated and the generated Raman scattered light is detected.

Sixth step: A stress value is calculated from the obtained Raman spectrum. ◆ Seventh step: The obtained stress value is displayed on the monitor.

This flow chart is for measuring the stress at one location. FIG. 14 shows a basic flow chart of another invention. This is an example in which an ultraviolet laser is used instead of the laser in the embodiment of FIG.

In the case of measuring stress at two or more places like the stress distribution measurement, the following steps are performed as shown in the basic flow chart of FIG. ◆ First step: Specify the measurement conditions, the number of measurement data or the number of measurement repetitions.

Second step: The sample is irradiated with an electron beam, and the generated secondary electrons are detected. ◆ Third step: Observe the sample morphology (visualization) and select the measurement point.

Fourth step: the sample is moved so that the selected measurement point and the laser irradiation point coincide with each other (specification of the measurement point). ◆ Fifth step: The laser is irradiated and the generated Raman scattered light is detected.

Sixth step: A stress value is calculated from the obtained Raman spectrum. ◆ 7th step: 1 step Move the sample and judge whether it is the specified number of data or the specified number of repetitions. If less than that, the second to sixth steps are repeated.

Eighth step: The obtained stress value and stress distribution chart are displayed on the monitor. FIG. 16 shows a basic flow chart of another invention. This is an example in which an ultraviolet laser is used instead of the laser in the embodiment of FIG.

FIG. 17 shows a basic flow chart of another invention. When the entire region of stress measurement can be observed by one-time sample morphology observation (visualization), the following steps are performed as shown in FIG. ◆ First step: Specify the measurement conditions.

Second step: The sample is irradiated with an electron beam and the generated secondary electrons are detected. ◆ Third step: Observe the sample morphology (visualization) and select the measurement point.

Fourth step: The number of measurement data or the number of measurement repetitions is designated. ◆ Fifth step: Move the sample, and select the measurement point and layout.
Match the irradiation position (specification of measurement position).

Sixth step: The laser is irradiated and the generated Raman scattered light is detected. ◆ Seventh step: Calculate a stress value from the obtained Raman spectrum.

Eighth step: 1 step Move the sample,
It is judged whether or not it is equal to or greater than the specified number of data or the specified number of repetitions. If it is less than that, the fifth to seventh steps are repeated. ◆ Ninth step: Monitor the obtained stress value and stress distribution chart-
To display.

FIG. 18 shows a basic flow chart of another invention. This is an example in which an ultraviolet laser is used instead of the laser in the embodiment of FIG.

[0082]

As described above, the method according to the present invention detects secondary electrons generated by irradiating an electron beam to visualize and specify a measurement point, which has been difficult in the past. Very small area (sub-micrometer or nanometer)
There is an effect that the stress value or the stress distribution state of the datum can be grasped.

Since the apparatus according to the present invention is provided with an electron gun for generating an electron beam, a scanning mechanism for scanning the electron beam, and a detector for detecting secondary electrons generated from the sample, This has the effect of accurately grasping the stress value or stress distribution state of the extremely small portion (sub-micrometer or nanometer order).

Further, by performing the stress measurement in vacuum, it is possible to reduce the attenuation of the intensity of the laser light or the ultraviolet laser light or the intensity of the electron beam, and it is possible to obtain the effect of highly accurate stress measurement. is there.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a stress measuring device according to an embodiment of the present invention.

FIG. 2 is a configuration diagram of a stress measuring device according to an embodiment of the present invention.

FIG. 3 is a configuration diagram of a stress measuring device according to an embodiment of the present invention.

FIG. 4 is a configuration diagram of a stress measuring device according to an embodiment of the present invention.

FIG. 5 is a configuration diagram of a stress measuring device according to an embodiment of the present invention.

FIG. 6 is a configuration diagram of a stress measuring device according to an embodiment of the present invention.

FIG. 7 is a configuration diagram of a stress measuring device according to an embodiment of the present invention.

FIG. 8 is a configuration diagram of a stress measuring device according to an embodiment of the present invention.

FIG. 9 is a configuration diagram of a stress measuring device according to an embodiment of the present invention.

FIG. 10 is a configuration diagram of a stress measuring device according to another embodiment of the present invention.

FIG. 11 is a configuration diagram of a semiconductor manufacturing apparatus with a stress measuring device according to an embodiment of the present invention.

FIG. 12 is a configuration diagram of a semiconductor manufacturing apparatus with a stress measuring device according to another embodiment of the present invention.

FIG. 13 is a flowchart of a stress measuring method according to an embodiment of the present invention.

FIG. 14 is a flowchart of a stress measuring method according to another embodiment of the present invention.

FIG. 15 is a flowchart of a stress measuring method according to another embodiment of the present invention.

FIG. 16 is a flowchart of a stress measuring method according to another embodiment of the present invention.

FIG. 17 is a flowchart of a stress measuring method according to another embodiment of the present invention.

FIG. 18 is a flowchart of a stress measuring method according to another embodiment of the present invention.

[Explanation of symbols]

1 ... Electron gun, 2 ... Electron beam, 3 ... Condenser lens, 4 ...
Deflection coil, 5 ... Objective lens, 6 ... Sample, 7 ... Detector,
8 ... Computer, 9 ... Image processing device, 10 ... Laser light source, 11 ... Laser light, 12 ... Mirror, 13 ... Objective lens, 14 ... Hough mirror, 15 ... Spectroscope, 16 ... Detector, 17 ... Fine movement stage, 18 ... Vacuum chamber, 19 ... Ultraviolet laser light source, 20 ... Ultraviolet laser light, 21 ... Ultraviolet mirror,
22 ... Ultraviolet objective lens, 23 ... Ultraviolet hafer mirror,
24 ... Miller, 25 ... Miller, 26 ... Fine movement stage with moving or rotating mechanism, 27 ... Miller for UV, 28 ... Miller for UV, 29 ... Window, 30 ... Window, 31 ... Window for UV, 32 ...
UV window, 33 ... Belger, 34 ... Evaporation source, 35 ... Heater, 36 ... Heater power supply, 37 ... Bias voltage.

Claims (18)

[Claims] 1. A laser light source, an objective lens for focusing laser light in a spot shape on the surface of an object to be stressed, a half mirror for guiding scattered light to a spectrometer, and a spectroscope. In the stress measurement method using Raman spectroscopy, the secondary electron generated by irradiating an electron beam is detected, and the measurement value is visualized and specified to determine the stress value or the stress distribution state of the extremely small portion. A method for measuring stress, which comprises measuring. 2. An ultraviolet laser light source, an ultraviolet objective lens for narrowing the ultraviolet laser light into a spot shape on the surface of an object to be stressed, and an ultraviolet hafmirer for guiding scattered light to a spectrometer. −
And a stress measurement method by ultraviolet Raman spectroscopy provided with a spectroscope, by detecting secondary electrons generated by irradiating an electron beam and visualizing and specifying the measurement point,
A method for measuring stress, which comprises measuring a stress value or a stress distribution state in an extremely small portion. 3. The stress measuring method according to claim 1, wherein the irradiation position of the electron beam and the irradiation position of the laser are made to coincide with each other. 4. The stress measuring method according to claim 1, wherein the beam axis of the electron beam and the optical axis of the laser are aligned with each other. 5. The stress measuring method according to claim 1, wherein the beam axis of the electron beam and the optical axis of the laser are independent. 6. A Raman equipped with a laser light source, an objective lens for squeezing the laser light into a spot on the surface of an object to be stressed, a half mirror for guiding scattered light to a spectrometer, and a spectroscope. A stress measuring device using spectroscopy, comprising: an electron gun, a scanning mechanism for scanning an electron beam generated from the electron gun, and a secondary electron detector. 7. An ultraviolet laser light source, an ultraviolet objective lens for narrowing the ultraviolet laser light into a spot on the surface of an object to be stress-stressed, and an ultraviolet hafmirer for guiding scattered light to a spectrometer. −
And a stress measuring device by ultraviolet Raman spectroscopy including a spectroscope, comprising an electron gun, a scanning mechanism for scanning an electron beam generated from the electron gun, and a secondary electron detector. Stress measuring device. 8. The stress measuring device according to claim 6, wherein the irradiation position of the electron beam and the irradiation position of the laser are made to coincide with each other. 9. The stress measuring device according to claim 6, wherein the beam axis of the electron beam is aligned with the optical axis of the laser. 10. The stress measuring apparatus according to claim 6, wherein the beam axis of the electron beam and the optical axis of the laser are independent. 11. The stress measuring method according to claim 1, wherein the stress measurement is performed in a vacuum. 12. The stress measurement is performed in the range of 10 μPa to 50 kPa.
The stress measuring method according to any one of claims 1 to 5, wherein the stress measuring method is performed in a vacuum of a certain degree. 13. The stress measuring device according to claim 6, wherein at least the light path of the light of the laser or the ultraviolet laser or the path of the electron beam is evacuated. 14. The stress measuring device according to claim 6, wherein at least the optical path of the light of the laser or the ultraviolet laser or the path of the electron beam is evacuated to about 10 μPa to 50 kPa. . 15. The stress measuring method according to any one of claims 1 to 5 or 11 or 12, or the stress measuring device according to any one of claims 6 to 10 or 13 or 14 is used. A semiconductor manufacturing method characterized by the above. 16. A stress measuring method according to any one of claims 1 to 5 or 11 or 12, or a stress measuring device according to any one of claims 6 to 10 or 13 or 14 is used. A semiconductor manufacturing apparatus characterized by the above. 17. A semiconductor manufacturing process using the semiconductor manufacturing method according to claim 15 or the semiconductor manufacturing apparatus according to claim 16. 18. A semiconductor manufactured by using the semiconductor manufacturing process according to claim 17.